Digital papillary adenocarcinoma: The Role of Ultrasound in Early Diagnosis and follow-up, and a review of the literature

Digital papillary adenocarcinoma: The Role of Ultrasound in Early Diagnosis and follow-up, and a review of the literature | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Digital papillary adenocarcinoma: The Role of Ultrasound in Early Diagnosis and follow-up, and a review of the literature Vincenza Amoruso, Letizia Castelli, Patrizia Matano, Giacomo Montaldi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6198500/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Digital papillary adenocarcinoma (DPAC) is a rare and aggressive cancer that has a significant potential for metastasis. It originates from the skin of the fingers, specifically from the sweat glands. In this report, we present a case of DPAC that was first diagnosed using ultrasound and subsequently confirmed through histological analysis. To the best of our knowledge the literature, does not provide an ultrasound description for this type of tumour; we believe it is essential to offer a clinical description for sonographers who may encounter similar cases. Additionally, early diagnosis enhances prognosis. This report supports using ultrasound as a diagnostic tool for skin cancer physicians. Digital papillary adenocarcinoma ultrasound skin cancer case report Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Most lesions arising from the skin or subcutaneous tissues of the fingers are benign. The most common pathologies are ganglion cysts (50–80%), giant cell tumours of the tendon sheath (7–12%), and epidermal inclusion cysts (5–9%) [1;2]. However, attention should be paid to signs of malignancy, as squamous cell carcinoma and basal cell carcinoma are the malignant tumours that more frequently affect the skin, particularly the fingers of the hands. [ 3 ]. Digital papillary adenocarcinoma (DPAC) is an extremely rare malignant tumour that originates from sweat glands, mainly located in the fingers. Its estimated annual incidence is about 0.8 cases per 1,000,000 individuals [ 4 ]. DPAC occurs most commonly in middle-aged adults, with a slight predominance in men. Although it often develops in the hands, it may occasionally occur in the feet [ 4 ]. It presents as a painless, slow-growing nodule or mass: it may appear as a subcutaneous nodule that can sometimes be mistaken for benign lesions like cysts or warts. Histophatologically, DPAC has distinctive feature that differentiate it from other sweat gland tumors. Diagnosis of DPAC by histopathologic examination can be challenging, but early and accurate identification is critical because of its significant metastatic potential, with reported rates ranging from 14–41% [5; 6 ;7; 8]. Diagnosis is established primarily through histopathologic after biopsy or surgical excision of the lesion, while imaging modalities play a key role in determining the extent of local invasion and identifying potential metastases. The primary approach for managing of DPAC is wide local excision with clear margins, reserving amputation for cases of extensive local invasion. In cases of metastasis or incomplete resection, adjuvant therapies such as radiotherapy or chemotherapy can be used to improve outcomes. Long-term monitoring is essential due to the significant risk of recurrence and metastasis. Clinical outcomes are influenced by the stage at diagnosis, presence of metastases, and the completeness of surgical excision. Early diagnosis and appropriate follow-up care are critical in the management of skin cancer: early diagnosis and subsequent complete resection, in fact, are associated with favorable outcomes, whereas the presence of an advanced stage of disease with the presence of metastases is linked to a poor prognosis. Ultrasound (US), as a noninvasive, accessible, and effective imaging modality, plays a key role in both the diagnostic process and ongoing management. Its utility lies in its ability to provide detailed images in real time, making it a valuable tool to guide diagnosis and monitor progression or recurrence of skin cancers [ 9 ]. The literature does not provide an ultrasound description for DPCA. In this study, we aim to highlight the critical role of ultrasound in facilitating accurate diagnosis and supporting longitudinal management of patients with DPAC. Specifically, in this case report we present a case of DPAC involving the third finger of the right hand. The diagnosis was made by high-resolution ultrasonography (US) and confirmed by histopathological examination, following which the patients underwent surgical treatment and was managed in follow-up. An 81-year-old right-handed Caucasian - male presented to our department with a six-month history of a painless, solid, smooth, and fixed 1 × 1 × 8 cm nodule on the dorsal aspect of the proximal phalanx of the right middle finger (Fig. 1). US imaging was performed using an MHz 3–22 linear stick probe in transverse and longitudinal sections. The lesion appeared as a well-circumscribed, homogeneous, subdermal mass resting on the extensor tendon of the third finger on the dorsal ulnar side. On ultrasonography, the mass showed a finely heterogeneous echotexture with vascularization on power Doppler, both peripheral and central. One vascular pole appeared to supply the lesion via a central vessel (Fig. 2). Given these findings, urgent excision with narrow margin was performed for accurate and reliable histopathological analysis. The lesion was excised with 3-mm peripheral margins and closed with a simple suture under local anesthesia (Fig. 3). Histopathological examination of the excised specimen confirmed the diagnosis of DPAC. The postoperative course was uneventful (Fig. 4, Fig. 5). At the three weeks follow-up, the patient maintained a wide range of motion without pain (Fig. 4). During the first follow-up, the ultrasound scan revealed the area of the resected lesion and the scar tissue in both transverse and longitudinal sections, situated above the long extensor tendon of the uninjured third toe (Fig. 5). This method enables us to detect any local tumour recurrence at an early stage. No evidence of local or regional recurrence was identified during each of his scheduled clinical surveillance appointments every four months. No palpable axillary lymphadenopathy was detected, and annual chest radiography showed no radiological signs of pulmonary metastases. The patient will be monitored for five years before being discharge from follow-up. Discussion DPAC is a rare malignant neoplasm that originates from the eccrine sweat glands and predominantly affects the distal phalanges of the fingers and toes. This condition primarily affects males between 50 and 70 years, with a male-to-female ratio ranging from 4:1 to 9:1 [ 4 ]. Histophatologically, DPAC is characterized by tubular, cystic, and papillary structures, with papillary projections extending into cystic cavities. [ 6 ]. Immunohistochemistry is essential for DPAC diagnosis, with typical markers including CK7 and CK19 for confirmation of glandular origin; S-100 for differentiation from neurogenic lesions; Carcinoembryonic Antigen (CEA), indicating epithelial origin; p63, useful for identifying basal cells and Ki-67, reflecting high proliferative activity [ 10 ]. The combination of structural features and immunohistochemical findings allows differentiation from other more common or less aggressive lesions [ 10 ]. US is an increasingly utilized diagnostic modality for assessing cutaneous tumors: it is a powerful tool that provides precise measurements of tumor size, including thickness. It assesses the involvement of deeper layers, thereby enhancing loco-regional staging accuracy, instilling confidence in its precision. US allows the classification of epitheliomas into superficial (thickness < 5 mm) or deep (thickness ≥ 5 mm), helping to decide on non-surgical treatments like brachytherapy. It is particularly effective in identifying infiltration of fascia, muscles, cartilage, or bone, guiding the need for more aggressive surgical approaches [ 11 ]. Preoperative US mapping is a key tool the in management of skin cancer. It identifies neurovascular structures and non-palpable satellite lesions, optimizing surgical planning by minimizing surgical defects and reducing operative time, while also improving cosmetic outcomes. Despite its many advantages, US remains surprisingly underutilized in the fields of dermatology and surgical oncology. This underscores the need for greater integration and awareness of its potential in the management of skin cancer, sparking curiosity and motivation to explore its benefits [ 9 ]. In our clinical case, US examination allowed us to assess the echostructure and margins of the mass, enabling the timely collection of an appropriate sample for histological analysis, significantly reducing diagnostic timeline, and improving the patient’s prognosis. Additionally, this case report aims to provide a representative US image of DPAC, that can serve as a valuable reference for clinicians who may encounter this neoplasm in practice before sending the sample for histological examination, which remains the gold standard for definitive diagnosis. The distal location of DPAC makes it suitable for reconstruction by inverted homo-digital island flaps, which allow excellent postoperative mobility. The patient described in this paper had a small mass that required only a simple surgical suture. As a result, the healing process was successful, allowing the preservation of third finger mobility, as already evident in the literature [ 12 ]. Regular clinical follow-up is essential to monitor potential pulmonary metastases: we strongly recommend the integration of US into the follow-up process, as it provides a non-invasive and rapid method for identifying recurrences and facilitating timely intervention. Conclusion DPAC is a rare but very aggressive tumour with considerable metastatic potential. Late or inaccurate diagnosis can have serious consequences on patient outcome. US has proven to be a valuable tool in facilitating early diagnosis and enabling effective follow-up, and its routine application should be strongly recommended in the management of this neoplasm and skin lesions. This clinical case is intended to show how such a mass can be seen by US. It is worth noting that there are no cases of such tumors studied with US in the literature, which highlights the need for further research in this area. US has emerged as a valuable tool to facilitate early diagnosis and enable effective follow-up in the management of DPAC. Declarations I declare that the patient has consented to the proposed medical treatment and publication of his clinical case in this case report. Ethics approval This is a case report; no ethical approval is required. Consent for publication The patient gave only verbal consent to publication. All details that might disclose patient identity are anonymized. Data Availability Statement The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request. Competing interests The authors report no competing interests. Disclosure Statement The author(s) have no conflict of interest to disclose. Authors' contributions Vincenza Amoruso and Giacomo Montaldi designed, conceived, and contribuited to draftig the study. Giacomo Montaldi contributed to interpreting the results. Letizia Castelli supervised the development of the study and undertook the critical revision of the manuscript. The authors read and approved the final manuscript. Acknowledgements The authors express their gratitude to MD Patrizia Matano, a plastic surgery specialist, for her clinical assistance and for providing the ultrasound equipment used for this case report at her clinic, the Center for Plastic Surgery and Aesthetic Medicine, located in Albenga (SV17031). References Hsu CS, Hentz VR, Yao J (2007) Tumours of the hand. Lancet Oncol. ;8(2):157 – 66. doi: 10.1016/S1470-2045(07)70035-9. PMID: 17267330 Nahra ME, Bucchieri JS (2004) Ganglion cysts and other tumor related conditions of the hand and wrist. Hand Clin. ;20(3):249 – 60, v. 10.1016/j.hcl.2004.03.015 . PMID: 15275684 Ilyas EN, Leinberry CF, Ilyas AM (2012) skin cancers of the hand and upper extremity. J Hand Surg Am. ;37(1):171-8. 10.1016/j.jhsa.2011.10.042 . PMID: 22196297 Rismiller K, Knackstedt TJ (2018) Aggressive digital papillary adenocarcinoma: population-based analysis of incidence, demographics, treatment, and outcomes. Dermatol Surg. ;44(7):911–917. 10.1097/DSS.0000000000001483 . PMID: 29578881 Kao GF, Helwig EB, Graham JH (1987) Aggressive digital papillary adenoma and adenocarcinoma. A clinicopathological study of 57 patients, with histochemical, immunopathological, and ultrastructural observations. J Cutan Pathol 14(3):129–146. 10.1111/j.1600-0560 1987.tb00488.x. PMID: 3301927 Duke WH, Sherrod TT, Lupton GP (2000) Aggressive digital papillary adenocarcinoma (aggressive digital papillary adenoma and adenocarcinoma revisited). Am J Surg Pathol. ;24(6):775 – 84. 10.1097/00000478-200006000-00002 . PMID: 10843279 Weingertner N, Gressel A, Battistella M, Cribier B (2017) Aggressive digital papillary adenocarcinoma: A clinicopathological study of 19 cases. J Am Acad Dermatol 77(3):549–558. .e1Epub 2017 May 9. PMID: 28495496 Vanderbilt C, Brenn T, Moy AP, Harloe G, Ariyan C, Athanasian E, Busam KJ (2022) Association of HPV42 with digital papillary adenocarcinoma and the use of in situ hybridization for its distinction from acral hidradenoma and diagnosis at non-acral sites. Mod Pathol 35(10):1405–1410. 10.1038/s41379-022-01094-8 Epub 2022 May 10. PMID: 35538210 Catalano O, Roldán FA, Varelli C, Bard R, Corvino A, Wortsman X (2019) Skin cancer: findings and role of high-resolution ultrasound. J Ultrasound 22(4):423–431. 10.1007/s40477-019-00379-0 Epub 2019 May 8. PMID: 31069756; PMCID: PMC6838298 Yagci S, Terzi A, Albayati A, Uysal AC, Clinical (2024) Histopathological and immunohistochemical aspects of digital papillary adenocarcinoma: a case report and literature review. Turk Patoloji Derg 40(1):69–73. 10.5146/tjpath.2023.01606 PMID: 37350642; PMCID: PMC10823785 Goyal U, Kim Y, Tiwari HA, Witte R, Stea B (2015) A pilot study of ultrasound-guided electronic brachytherapy for skin cancer. J Contemp Brachytherapy 7(5):374–380. 10.5114/jcb.2015.55538 Epub 2015 Oct 30. PMID: 26622244; PMCID: PMC4663218 Knackstedt RW, Knackstedt TJ, Findley AB, Piliang M, Jellinek NJ, Bernard SL, Vidimos A (2017) Aggressive digital papillary adenocarcinoma: treatment with Mohs micrographic surgery and an update of the literature. Int J Dermatol 56(10):1061–1064. 10.1111/ijd.13712 Epub 2017 Aug 21. PMID: 28832985 Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6198500","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":426920457,"identity":"61cc1b9b-78dc-4e13-84d2-545699a9f02c","order_by":0,"name":"Vincenza Amoruso","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABEklEQVRIiWNgGAWjYDACZnQBfmbmA0BKQoZ4LZLtbQkgLTzEW2tw5owBiMapxeA478EPH3fUyTOwn058XNlWJ2dwI+fzqxs1FjwM7IePbsCm5TBfsuTMM2yGDTy5mw3Pth02lryRu8065xjQYTxpaTewaJFs5jFj5m3jYWxgyN0m2dh2ILEPqMU4hw2oRYLHDKeWv20S9g38b0Fa6hIbbuQ8M875h1sLPzNQC2ObQWKDBNgW5sQJZ84wP85tw6vFWLK3LSG5TeLtZsOGc0C/tLeZMef2SfCw4fALG/8Zww8/2+ps+/lzNz5sKKuTA0bl488534AM9sPHsGlB6EVmS6CLEATMH0hRPQpGwSgYBcMeAAB6X1ysH9JIgAAAAABJRU5ErkJggg==","orcid":"https://orcid.org/0000-0001-8267-2326","institution":"Recovery and Functional Rehabilitation Unit, Rehabilitation Department, Santa Corona Hospital, 17027 Pietra Ligure, Italy; Musculoskeletal Ultrasound School, Italian Society for Ultrasound in Medicine and Biology, Bologna, Italy.","correspondingAuthor":true,"prefix":"","firstName":"Vincenza","middleName":"","lastName":"Amoruso","suffix":""},{"id":426920881,"identity":"42d286ea-5396-4778-acbc-ba9ddaeaf95d","order_by":1,"name":"Letizia Castelli","email":"","orcid":"","institution":"Department of Neurosciences, Università Cattolica del Sacro Cuore, 00168, Rome, Italy.","correspondingAuthor":false,"prefix":"","firstName":"Letizia","middleName":"","lastName":"Castelli","suffix":""},{"id":426920882,"identity":"e919b31c-1779-4826-a045-3c0c47e29a1b","order_by":2,"name":"Patrizia Matano","email":"","orcid":"","institution":"Private practice in Aesthetic medicine, Center for Aesthetic Surgery and Aesthetic Medicine, 17031, Albenga, Italy.","correspondingAuthor":false,"prefix":"","firstName":"Patrizia","middleName":"","lastName":"Matano","suffix":""},{"id":426920883,"identity":"fe983cc4-d555-47c0-b42b-0f2ae42fea16","order_by":3,"name":"Giacomo Montaldi","email":"","orcid":"","institution":"Private practice in Aesthetic medicine, Center for Aesthetic Surgery and Aesthetic Medicine, 17031, Albenga, Italy; Musculoskeletal Ultrasound School, Italian Society for Ultrasound in Medicine and Biology, Bologna, Italy.","correspondingAuthor":false,"prefix":"","firstName":"Giacomo","middleName":"","lastName":"Montaldi","suffix":""}],"badges":[],"createdAt":"2025-03-10 21:07:08","currentVersionCode":1,"declarations":{"humanSubjects":true,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":true,"humanSubjectConsent":true,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6198500/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6198500/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":78426693,"identity":"a21a09dd-8d85-4176-9e92-cd57f1b81f03","added_by":"auto","created_at":"2025-03-13 06:36:45","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":442759,"visible":true,"origin":"","legend":"\u003cp\u003eAn 81-year-old right-handed Caucasian - male presented to our department with a six-month history of a painless, solid, smooth, and fixed 1 × 1 × 8 cm nodule on the dorsal aspect of the proximal phalanx of the right middle finger.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/30ca798b5653fe8f61c266b7.png"},{"id":78424925,"identity":"b01de15d-0ded-4e3b-b7eb-74824ed9e622","added_by":"auto","created_at":"2025-03-13 06:20:45","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":262435,"visible":true,"origin":"","legend":"\u003cp\u003eUS imaging of DPCA. The lesion appeared as a well-circumscribed, homogeneous, subdermal mass resting on the extensor tendon of the third finger on the dorsal ulnar side. On ultrasonography, the mass showed a finely heterogeneous echotexture with vascularization on power Doppler, both peripheral and central. One vascular pole appeared to supply the lesion via a central vessel.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/4c18d026a1106f6fb2d216d2.png"},{"id":78424926,"identity":"b226b3c3-85f6-49df-b955-288842b1ae4f","added_by":"auto","created_at":"2025-03-13 06:20:45","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":254982,"visible":true,"origin":"","legend":"\u003cp\u003eExcision with narrow margin was performed for accurate and reliable histopathological analysis. The lesion was excised with 3-mm peripheral margins and closed with a simple suture under local anesthesia.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/eefd0489b0b3a007e04bda8a.png"},{"id":78424930,"identity":"4ed96f48-3442-4c9a-9e67-d2e07f648a38","added_by":"auto","created_at":"2025-03-13 06:20:45","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":392476,"visible":true,"origin":"","legend":"\u003cp\u003eAt the follow-up, the patient maintained a wide range of motion without pain.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/08eac1e8c1ba221c418774a1.png"},{"id":78426268,"identity":"fe4ad123-3a16-4983-b331-fb6aa2e74d12","added_by":"auto","created_at":"2025-03-13 06:28:45","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":241776,"visible":true,"origin":"","legend":"\u003cp\u003eAt the follow-up, the ultrasound scan displays the area of the resected lesion and the scar region in both transverse (on the left) and longitudinal sections (on the right) above the long extensor tendon of the uninjured third toe.\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/b04902df46bb71b72e874f43.png"},{"id":78536341,"identity":"ada0ac51-ae98-47fb-add6-c55db76755c1","added_by":"auto","created_at":"2025-03-14 14:57:45","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2384704,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6198500/v1/932ebbf8-f037-4769-a385-3d91cb495c94.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003e\u003cstrong\u003eDigital papillary adenocarcinoma: The Role of Ultrasound in Early Diagnosis and follow-up, and a review of the literature\u003c/strong\u003e\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMost lesions arising from the skin or subcutaneous tissues of the fingers are benign. The most common pathologies are ganglion cysts (50\u0026ndash;80%), giant cell tumours of the tendon sheath (7\u0026ndash;12%), and epidermal inclusion cysts (5\u0026ndash;9%) [1;2]. However, attention should be paid to signs of malignancy, as squamous cell carcinoma and basal cell carcinoma are the malignant tumours that more frequently affect the skin, particularly the fingers of the hands. [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDigital papillary adenocarcinoma (DPAC) is an extremely rare malignant tumour that originates from sweat glands, mainly located in the fingers. Its estimated annual incidence is about 0.8 cases per 1,000,000 individuals [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. DPAC occurs most commonly in middle-aged adults, with a slight predominance in men. Although it often develops in the hands, it may occasionally occur in the feet [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. It presents as a painless, slow-growing nodule or mass: it may appear as a subcutaneous nodule that can sometimes be mistaken for benign lesions like cysts or warts. Histophatologically, DPAC has distinctive feature that differentiate it from other sweat gland tumors. Diagnosis of DPAC by histopathologic examination can be challenging, but early and accurate identification is critical because of its significant metastatic potential, with reported rates ranging from 14\u0026ndash;41% [5; 6 ;7; 8]. Diagnosis is established primarily through histopathologic after biopsy or surgical excision of the lesion, while imaging modalities play a key role in determining the extent of local invasion and identifying potential metastases. The primary approach for managing of DPAC is wide local excision with clear margins, reserving amputation for cases of extensive local invasion. In cases of metastasis or incomplete resection, adjuvant therapies such as radiotherapy or chemotherapy can be used to improve outcomes. Long-term monitoring is essential due to the significant risk of recurrence and metastasis. Clinical outcomes are influenced by the stage at diagnosis, presence of metastases, and the completeness of surgical excision. Early diagnosis and appropriate follow-up care are critical in the management of skin cancer: early diagnosis and subsequent complete resection, in fact, are associated with favorable outcomes, whereas the presence of an advanced stage of disease with the presence of metastases is linked to a poor prognosis. Ultrasound (US), as a noninvasive, accessible, and effective imaging modality, plays a key role in both the diagnostic process and ongoing management. Its utility lies in its ability to provide detailed images in real time, making it a valuable tool to guide diagnosis and monitor progression or recurrence of skin cancers [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. The literature does not provide an ultrasound description for DPCA.\u003c/p\u003e \u003cp\u003eIn this study, we aim to highlight the critical role of ultrasound in facilitating accurate diagnosis and supporting longitudinal management of patients with DPAC. Specifically, in this case report we present a case of DPAC involving the third finger of the right hand. The diagnosis was made by high-resolution ultrasonography (US) and confirmed by histopathological examination, following which the patients underwent surgical treatment and was managed in follow-up.\u003c/p\u003e \u003cp\u003eAn 81-year-old right-handed Caucasian - male presented to our department with a six-month history of a painless, solid, smooth, and fixed 1 \u0026times; 1 \u0026times; 8 cm nodule on the dorsal aspect of the proximal phalanx of the right middle finger (Fig.\u0026nbsp;1). US imaging was performed using an MHz 3\u0026ndash;22 linear stick probe in transverse and longitudinal sections. The lesion appeared as a well-circumscribed, homogeneous, subdermal mass resting on the extensor tendon of the third finger on the dorsal ulnar side. On ultrasonography, the mass showed a finely heterogeneous echotexture with vascularization on power Doppler, both peripheral and central. One vascular pole appeared to supply the lesion via a central vessel (Fig.\u0026nbsp;2). Given these findings, urgent excision with narrow margin was performed for accurate and reliable histopathological analysis. The lesion was excised with 3-mm peripheral margins and closed with a simple suture under local anesthesia (Fig.\u0026nbsp;3). Histopathological examination of the excised specimen confirmed the diagnosis of DPAC. The postoperative course was uneventful (Fig.\u0026nbsp;4, Fig.\u0026nbsp;5). At the three weeks follow-up, the patient maintained a wide range of motion without pain (Fig.\u0026nbsp;4). During the first follow-up, the ultrasound scan revealed the area of the resected lesion and the scar tissue in both transverse and longitudinal sections, situated above the long extensor tendon of the uninjured third toe (Fig.\u0026nbsp;5). This method enables us to detect any local tumour recurrence at an early stage.\u003c/p\u003e \u003cp\u003eNo evidence of local or regional recurrence was identified during each of his scheduled clinical surveillance appointments every four months. No palpable axillary lymphadenopathy was detected, and annual chest radiography showed no radiological signs of pulmonary metastases. The patient will be monitored for five years before being discharge from follow-up.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eDPAC is a rare malignant neoplasm that originates from the eccrine sweat glands and predominantly affects the distal phalanges of the fingers and toes. This condition primarily affects males between 50 and 70 years, with a male-to-female ratio ranging from 4:1 to 9:1 [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHistophatologically, DPAC is characterized by tubular, cystic, and papillary structures, with papillary projections extending into cystic cavities. [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Immunohistochemistry is essential for DPAC diagnosis, with typical markers including CK7 and CK19 for confirmation of glandular origin; S-100 for differentiation from neurogenic lesions; Carcinoembryonic Antigen (CEA), indicating epithelial origin; p63, useful for identifying basal cells and Ki-67, reflecting high proliferative activity [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. The combination of structural features and immunohistochemical findings allows differentiation from other more common or less aggressive lesions [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eUS is an increasingly utilized diagnostic modality for assessing cutaneous tumors: it is a powerful tool that provides precise measurements of tumor size, including thickness. It assesses the involvement of deeper layers, thereby enhancing loco-regional staging accuracy, instilling confidence in its precision. US allows the classification of epitheliomas into superficial (thickness\u0026thinsp;\u0026lt;\u0026thinsp;5 mm) or deep (thickness\u0026thinsp;\u0026ge;\u0026thinsp;5 mm), helping to decide on non-surgical treatments like brachytherapy. It is particularly effective in identifying infiltration of fascia, muscles, cartilage, or bone, guiding the need for more aggressive surgical approaches [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Preoperative US mapping is a key tool the in management of skin cancer. It identifies neurovascular structures and non-palpable satellite lesions, optimizing surgical planning by minimizing surgical defects and reducing operative time, while also improving cosmetic outcomes.\u003c/p\u003e \u003cp\u003eDespite its many advantages, US remains surprisingly underutilized in the fields of dermatology and surgical oncology. This underscores the need for greater integration and awareness of its potential in the management of skin cancer, sparking curiosity and motivation to explore its benefits [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn our clinical case, US examination allowed us to assess the echostructure and margins of the mass, enabling the timely collection of an appropriate sample for histological analysis, significantly reducing diagnostic timeline, and improving the patient\u0026rsquo;s prognosis. Additionally, this case report aims to provide a representative US image of DPAC, that can serve as a valuable reference for clinicians who may encounter this neoplasm in practice before sending the sample for histological examination, which remains the gold standard for definitive diagnosis. The distal location of DPAC makes it suitable for reconstruction by inverted homo-digital island flaps, which allow excellent postoperative mobility. The patient described in this paper had a small mass that required only a simple surgical suture. As a result, the healing process was successful, allowing the preservation of third finger mobility, as already evident in the literature [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Regular clinical follow-up is essential to monitor potential pulmonary metastases: we strongly recommend the integration of US into the follow-up process, as it provides a non-invasive and rapid method for identifying recurrences and facilitating timely intervention.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eDPAC is a rare but very aggressive tumour with considerable metastatic potential. Late or inaccurate diagnosis can have serious consequences on patient outcome. US has proven to be a valuable tool in facilitating early diagnosis and enabling effective follow-up, and its routine application should be strongly recommended in the management of this neoplasm and skin lesions. This clinical case is intended to show how such a mass can be seen by US. It is worth noting that there are no cases of such tumors studied with US in the literature, which highlights the need for further research in this area. US has emerged as a valuable tool to facilitate early diagnosis and enable effective follow-up in the management of DPAC.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eI declare that the patient has consented to the proposed medical treatment and publication of his clinical case in this case report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis is a case report; no ethical approval is required.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe patient gave only verbal consent to publication. All details that might disclose patient identity are anonymized.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors report no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDisclosure Statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author(s) have no conflict of interest to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eVincenza Amoruso and Giacomo Montaldi designed, conceived, and contribuited to draftig the study. Giacomo Montaldi contributed to interpreting the results. Letizia Castelli supervised the development of the study and undertook the critical revision of the manuscript. The authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors express their gratitude to MD Patrizia Matano, a plastic surgery specialist, for her clinical assistance and for providing the ultrasound equipment used for this case report at her clinic, the Center for Plastic Surgery and Aesthetic Medicine, located in Albenga (SV17031).\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eHsu CS, Hentz VR, Yao J (2007) Tumours of the hand. Lancet Oncol. ;8(2):157\u0026thinsp;\u0026ndash;\u0026thinsp;66. doi: 10.1016/S1470-2045(07)70035-9. PMID: 17267330\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNahra ME, Bucchieri JS (2004) Ganglion cysts and other tumor related conditions of the hand and wrist. Hand Clin. ;20(3):249\u0026thinsp;\u0026ndash;\u0026thinsp;60, v. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.hcl.2004.03.015\u003c/span\u003e\u003cspan address=\"10.1016/j.hcl.2004.03.015\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 15275684\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eIlyas EN, Leinberry CF, Ilyas AM (2012) skin cancers of the hand and upper extremity. J Hand Surg Am. ;37(1):171-8. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1016/j.jhsa.2011.10.042\u003c/span\u003e\u003cspan address=\"10.1016/j.jhsa.2011.10.042\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 22196297\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eRismiller K, Knackstedt TJ (2018) Aggressive digital papillary adenocarcinoma: population-based analysis of incidence, demographics, treatment, and outcomes. Dermatol Surg. ;44(7):911\u0026ndash;917. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/DSS.0000000000001483\u003c/span\u003e\u003cspan address=\"10.1097/DSS.0000000000001483\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 29578881\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKao GF, Helwig EB, Graham JH (1987) Aggressive digital papillary adenoma and adenocarcinoma. A clinicopathological study of 57 patients, with histochemical, immunopathological, and ultrastructural observations. J Cutan Pathol 14(3):129\u0026ndash;146. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1600-0560\u003c/span\u003e\u003cspan address=\"10.1111/j.1600-0560\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e1987.tb00488.x. PMID: 3301927\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDuke WH, Sherrod TT, Lupton GP (2000) Aggressive digital papillary adenocarcinoma (aggressive digital papillary adenoma and adenocarcinoma revisited). Am J Surg Pathol. ;24(6):775\u0026thinsp;\u0026ndash;\u0026thinsp;84. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/00000478-200006000-00002\u003c/span\u003e\u003cspan address=\"10.1097/00000478-200006000-00002\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. PMID: 10843279\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWeingertner N, Gressel A, Battistella M, Cribier B (2017) Aggressive digital papillary adenocarcinoma: A clinicopathological study of 19 cases. J Am Acad Dermatol 77(3):549\u0026ndash;558. .e1Epub 2017 May 9. PMID: 28495496\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eVanderbilt C, Brenn T, Moy AP, Harloe G, Ariyan C, Athanasian E, Busam KJ (2022) Association of HPV42 with digital papillary adenocarcinoma and the use of in situ hybridization for its distinction from acral hidradenoma and diagnosis at non-acral sites. Mod Pathol 35(10):1405\u0026ndash;1410. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41379-022-01094-8\u003c/span\u003e\u003cspan address=\"10.1038/s41379-022-01094-8\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2022 May 10. PMID: 35538210\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eCatalano O, Rold\u0026aacute;n FA, Varelli C, Bard R, Corvino A, Wortsman X (2019) Skin cancer: findings and role of high-resolution ultrasound. J Ultrasound 22(4):423\u0026ndash;431. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s40477-019-00379-0\u003c/span\u003e\u003cspan address=\"10.1007/s40477-019-00379-0\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2019 May 8. PMID: 31069756; PMCID: PMC6838298\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eYagci S, Terzi A, Albayati A, Uysal AC, Clinical (2024) Histopathological and immunohistochemical aspects of digital papillary adenocarcinoma: a case report and literature review. Turk Patoloji Derg 40(1):69\u0026ndash;73. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5146/tjpath.2023.01606\u003c/span\u003e\u003cspan address=\"10.5146/tjpath.2023.01606\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003ePMID: 37350642; PMCID: PMC10823785\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGoyal U, Kim Y, Tiwari HA, Witte R, Stea B (2015) A pilot study of ultrasound-guided electronic brachytherapy for skin cancer. J Contemp Brachytherapy 7(5):374\u0026ndash;380. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.5114/jcb.2015.55538\u003c/span\u003e\u003cspan address=\"10.5114/jcb.2015.55538\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2015 Oct 30. PMID: 26622244; PMCID: PMC4663218\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eKnackstedt RW, Knackstedt TJ, Findley AB, Piliang M, Jellinek NJ, Bernard SL, Vidimos A (2017) Aggressive digital papillary adenocarcinoma: treatment with Mohs micrographic surgery and an update of the literature. Int J Dermatol 56(10):1061\u0026ndash;1064. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/ijd.13712\u003c/span\u003e\u003cspan address=\"10.1111/ijd.13712\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub 2017 Aug 21. PMID: 28832985\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Ospedale Santa Corona","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Digital papillary adenocarcinoma, ultrasound, skin cancer, case report","lastPublishedDoi":"10.21203/rs.3.rs-6198500/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6198500/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eDigital papillary adenocarcinoma (DPAC) is a rare and aggressive cancer that has a significant potential for metastasis. It originates from the skin of the fingers, specifically from the sweat glands. In this report, we present a case of DPAC that was first diagnosed using ultrasound and subsequently confirmed through histological analysis. To the best of our knowledge the literature, does not provide an ultrasound description for this type of tumour; we believe it is essential to offer a clinical description for sonographers who may encounter similar cases. Additionally, early diagnosis enhances prognosis. This report supports using ultrasound as a diagnostic tool for skin cancer physicians.\u003c/p\u003e","manuscriptTitle":"Digital papillary adenocarcinoma: The Role of Ultrasound in Early Diagnosis and follow-up, and a review of the literature","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-13 06:20:40","doi":"10.21203/rs.3.rs-6198500/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9ea63187-6796-4a09-ae1e-70f5b64bf8cd","owner":[],"postedDate":"March 13th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-03-13T06:20:41+00:00","versionOfRecord":[],"versionCreatedAt":"2025-03-13 06:20:40","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6198500","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6198500","identity":"rs-6198500","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}