Primary Cutaneous Endometriosis of Umbilicus

Loh SH, Seung-Hee Loh, Lew BL, Bark-Lynn Lew, Bark‐Lynn Lew, Sim WY, Woo-Young Sim, Woo‐Young Sim
Annals of dermatology · 2017 · vol. 29(5) , pp. 621 · doi:10.5021/ad.2017.29.5.621 · PMID:28966521 · PMC5597658 · W2754580245
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This case report describes a 38-year-old woman diagnosed with primary umbilical endometriosis presenting as a painful, bleeding nodule mistaken for a keloid, which was successfully treated with surgical excision.

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This paper reports a rare case of primary cutaneous endometriosis of the umbilicus (Villar’s nodule) in a 38-year-old woman with a 2.5×2.0 cm painful purple-brown umbilical nodule that became swollen and spontaneously bled during menstruation, without any prior surgical history. The authors used imaging to differentiate the lesion from diagnoses such as Sister Mary Joseph nodule and keloid, and confirmed the diagnosis by biopsy showing dilated glandular structures in the dermis surrounded by endometrial-type stroma with perivascular lymphocytic infiltration. Complete wide excision led to an uncomplicated postoperative course and no recurrence over 2 years, but the study is limited by its case-report design and the lack of broader comparative data. This paper is centrally about endometriosis — specifically a case of primary umbilical cutaneous endometriosis, which is a manifestation within the endometriosis spectrum (not adenomyosis).

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Abstract

Cutaneous endometriosis is defined by the presence of endometrial glands and/or stroma in skin and represents less than 1% of all ectopic endometrium. Cutaneous endometriosis is classified as primary and secondary. Primary cutaneous endometriosis appears without a prior surgical history and secondary cutaneous endometriosis mostly occurs at surgical scar tissue after abdominal operations. The most widely accepted pathogenesis of secondary endometriosis is the iatrogenic implantation of endometrial cells after surgery, such as laparoscopic procedures. However, the pathogenesis of primary endometriosis is still unknown. Umbilical endometriosis is composed only 0.4% to 4.0% of all endometriosis, however, umbilicus is the most common site of primary cutaneous endometriosis. A 38-year-old women presented with solitary 2.5×2.0-cm-sized purple to brown colored painful nodule on the umbilicus since 2 years ago. The patient had no history of surgical procedures. The skin lesion became swollen with spontaneous bleeding during menstruation. The skin lesion was diagnosed as a keloid at private hospital and has been treated with lesional injection of steroid for several times but there was no improvement. Imaging studies showed an enhancing umbilical mass without connection to internal organs. Biopsy specimen showed the several dilated glandular structures in dermis. They were surrounded by endometrial-type stroma and perivascular infiltration of lymphocytes. The patient was diagnosed as primary cutaneous endometriosis and skin lesion was removed by complete wide excision without recurrence. We report an interesting and rare case of primary umbilical endometriosis mistaken for a keloid and review the literatures.
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Introduction

Endometriosis is histopathologically defined by the pres- ence of endometrial glands and/or stroma outside of the endometrium1. Ectopic endometriosis could be developed in many other tissues, most commonly affects pelvic or- gans such as ovaries, fallopian tubes, uterine ligaments, pelvic wall2. Primary cutaneous umbilical endometriosis, which is also known as Villar ’s nodule, is a rare manifes- tation of endometriosis 3. Secondary endometriosis mostly occurs at surgical scar tissue after abdominal operations 4. The most widely accepted path ogenesis of secondary en- dometriosis is the iatrogenic implantation of endometrial cells after surgery, commonly after laparoscopic proce- dures 5. However, the pathogenesis of primary endome- triosis is still unknown. To date, umbilical endometriosis has been reported to rep- resent about 0.4% to 4.0% of all endometriosis and ac- counts for 30% to 40% cases of cutaneous endometriosis. Among cutaneous endometriosis, primary umbilical endo- metriosis was considered even less common. CASE REPORT A 38-year-old multigravida fema le visited our department because of a painful nodule on her umbilicus. The patient recalled that the lesion was observed 2 years ago and the SH Loh, et al 622 Ann Dermatol Fig. 2. (A, B) Specimen showed le- sions in the superficial dermis and deep dermis comprising dilated glan- dular structures, surrounded by cel- lular endometrial-type stroma (H&E; A: ×40, B: ×100, respectively). Fig. 1. About 2.5×2.0-cm-sized brownish to purple colored nodule on the umbilicus. lesion became swollen with spontaneous frank bleeding during menstruation. The pati ent had no history of surgi- cal procedure, nor any family history of malignancy. The nodule was first diagnosed as a keloid at a private clinic and had been treated with intralesional injection of steroid for several times without any signs of improvement. Physical examination revealed a 2.5×2.0-cm-sized brown- ish to purple colored nodule on the umbilicus (Fig. 1). Imaging studies were carried out for differential diagnosis with Sister Mary Joseph nodu le and keloid. Umbilical ul- trasonography showed a mass with heterogenous echoge- necity, increased vascularity and abdominal computed to- mography (CT) revealed enhancing mass at umbilicus without connection to abdom inal organs. Histopatho- logical examination showed d ilated glandular structures surrounded by cellular endomet rial-type stroma and deep perivascular infiltration of lymphocytes (Fig. 2). According to these findings, the umbilical lesion was diagnosed as primary cutaneous endometriosis and it was removed by local surgical excision. Postoperative period was un- remarkable and the patient was followed up for 2 years without recurrence.

Discussion

Cutaneous endometriosis repres ents 0.5% to 1.0% of all patients with ectopic endometriosis. Less than 30% of cu- taneous endometriosis presents without prior surgical op- erative history, which is termed as primary spontaneous cutaneous endometriosis 3. Umbilical endometriosis is composed 0.4% to 4.0% of all endometriosis, high as two-fifths of extragenital endometrioric lesions. Moreover, umbilicus is the most common site of primary cutaneous endometriosis 6. Umbilical endometriosis occurs in female of reproductive age and associated symptoms are cyclic pain, bleeding and swelling of the lesion according to the menstrual cycle4. Several possible pathogenesis of umbilical endometriosis were suggested by multiple investigators. The most com- monly accepted mechanisms are lymphatic or vascular migration, cellular metaplasia, and iatrogenic metastasis 5. Suggested theory includes migr ation of endometrial tissue from retrogression of menstr uation. Survival of endo- metrial implants after implantation may depend on local and systemic factors. Inflamma tory process is then stimu- lated by microvascular endothelial injury. Accordingly, it might enhance adhesion of tissu e implants in outside of endometrial tissues via production of adhesion molecules such as integrin and e-cadherins 7. Major etiologic patho- genesis of secondary umbilical endometriosis could be ex- plained by iatrogenic metastasis, endometrial cells implant in scars after surgery. In comparison, primary umbilical endometriosis may be explained by the theory of vascular or lymphatic migration. Primary Cutaneous Endometriosis of Umbilicus Vol. 29, No. 5, 2017 623 Table 1. Literature review of primary umbilical endometriosis

Reference

Age at diagnosis (yr) Age at initial (yr) Initial diagnosis Presenting symptom Treatment Theunissen and IJpma 9 47 47 Umbilical hernia Asymptomatic umbilical nodule Surgical excision Calagna et al. 10 33 33 Umbilical granuloma Spontaneous catamenial bleeding Surgical excision Chikazawa et al. 11 46 44 Swelling during mentrual period Surgical excision Chikazawa et al. 11 27 23 Pain during menstrual period Surgical excision Pariza and Mavrodin 12 26 25 Pain and discharge Surgical excision Paramythiotis et al. 13 46 - Uterine leiomyoma Abdominal and pelvic pain Total hysterectomy with excision of nodule Ghosh and Das 14 33 33 Umbilical endometriosis Cyclic pain and swelling Excisional biopsy Gin et al. 15 31 31 Swelling during mentrual period Surgical excision Kahlenberg and Laskey 16 24 20 Abcess Bloody discharge during menstrual period Surgical excision Fancellu et al. 17 24 24 Umbilical endometriosis Concomittant bleeding on menstruation Surgical excision Jaime et al. 3 33 33 Spontaneous bleeding Not described Efremidou et al. 18 44 38 ∼39 Granuloma Pain during menstrual period Surgical excision Kesici et al. 19 38 38 Omphalitis Umbilical secretion and mass Surgical excision Fernández-Aceñero and Córdova 4 38 35 Umbilical endometriosis with uterine fibroids Cyclic pain Abdominal hysterectomy with excision of nodule Dadhwal et al. 8 42 42 Cyclic pain and blackish discoloration Surgical excision Bagade and Guirguis 20 35 35 Umbilical endometriosis Spontaneous and cyclic bleeing Goserelin acetate, and then surgical excision Victory et al. 6 47 46 Umbilical bleeding Surgical excision Boesgaard-Kjer et al. 21 28.5 (mean age of 10 patients) - Periodic color change and tenderness Surgical excision Wiegratz et al. 22 27 25 Umbilical endometriosis Increasing cyclic pain Oral contraceptive, and then surgical excision Taniguchi et al. 23 45 42 Umbilical endometriosis Painful umbilical mass Surgical excision Chew et al. 24 44 44 Umbilical endometriosis Progressively enlarging umbilical nodule GnRH analogue leuprorelin acetate Claas-Quax et al. 25 27 27 Catamenial bleeding Surgical excision Sidani et al. 26 37 37 Cyclic swelling and discharge Surgical excision Sengupta et al. 27 29 28 Painful nodule Excisional biopsy Minaidou et al. 1 26 - Umbilical hernia Umbilical pain and dark purplish nodule Surgical excision Weng and Yang 5 37 - Cyclic bleeding Gestrinone, and then surgical excision Kim et al. 28 42 42 Epidermal cyst Size increase and pain Excisional biopsy Song et al. 29 25 23 Dermatofibroma Size increase, pain, discoloration Surgical excision Kyamidis et al. 30 37 27 Umbilical endometriosis Tenderness and occasional bleeding Not described SH Loh, et al 624 Ann Dermatol Twenty-nine published studies with primary umbilical en- dometriosis were identified in the literature written in English and Korean language during the period 2000 ∼ 2016 (Table 1) 1,3-6,8-30. Primary umbilical endometriosis is initially very rare condition, but it is now increasing in number. Based on all the reports, the mean age of patients was 35.1 years. Differential diagnosis of umbilical endometriosis includes keloid, metastasis of visceral carcinoma, which is referred as Sister Mary Joseph nodule and melanoma 3. Therefore, physicians should work on imaging studies such as ultra- sonography or CT or magnetic resonance imaging. Further- more, diagnosis must be con firmed histopathologically to exclude malignancy. More importantly, keloid is clinically very similar to umbilical endometriosis. Clinicians should pay particular attention to patients, especially history of surgery or trauma, and presenting symp toms that are re- lated to menstrual cycle. If treatment with steroid intrale- sional injection does not improve the symptom, umbilical endometriosis should be consid ered for differential diag- nosis. Surgical excision is the de finitive treatment. Hormonal therapy with gonadotropin-releasing hormone agonists, or- al contraceptive and danazol can be used before surgical excision to decrease the size of the lesion and make symp- tom relief 8,31. Recurrence rate is very rare9. In our case, the lesion was confirmed by umbi lical ultrasonography and abdominal CT and histopathological finding, and removed by local surgical excision. In conclusion, cutaneous e ndometriosis of umbilicus should now be recognized as a primary or metastatic pre- sentation or iatrogenic complication of endometriosis. Patients with primary umbilical endometriosis should un- dergo careful history and physi cal examination to rule out potential malignancies. Moreover, differential diagnosis with keloid is very important. If the lesion diagnosed with keloid has cyclic symptoms with menstrual period, and does not improve with treatment, umbilical endometriosis should be suspected. Surgical excision is the treatment of choice to prevent recurrence and to reduce the risk of ma- lignant transformation. CONFLICTS OF INTEREST The authors have nothing to disclose.

References

1. Minaidou E, Polymeris A, Vassiliou J, Kondi-Paphiti A, Karoutsou E, Katafygiotis P, et al. Primary umbilical endometriosis: case report and literature review. Clin Exp Obstet Gynecol 2012;39:562-564. 2. Yuen JS, Chow PK, Koong HN, Ho JM, Girija R. Unusual sites (thorax and umbilical hernial sac) of endometriosis. J R Coll Surg Edinb 2001;46:313-315. 3. Jaime TJ, Jaime TJ, Ormiga P, Leal F, Nogueira OM, Rodrigues N. Umbilical endometriosis: report of a case and its dermoscopic features. An Bras Dermatol 2013;88:121- 124. 4. Fernández-Aceñero MJ, Córdova S. Cutaneous endo- metriosis: review of 15 cases diagnosed at a single institution. Arch Gynecol Obstet 2011;283:1041-1044. 5. Weng CS, Yang YC. Images in clinical medicine. Villar's nodule--umbilical endometriosis. N Engl J Med 2011;364:e45. 6. Victory R, Diamond MP, Johns DA. Villar's nodule: a case report and systematic literature review of endometriosis externa of the umbilicus. J Minim Invasive Gynecol 2007;14:23-32. 7. Groothuis PG, Koks CA, de Goeij AF, Dunselman GA, Arends JW, Evers JL. Adhesion of human endometrium to the epithelial lining and extracellular matrix of amnion in vitro: an electron microscopic study. Hum Reprod 1998; 13:2275-2281. 8. Dadhwal V, Gupta B, Dasgupta C, Shende U, Deka D. Primary umbilical endometriosis: a rare entity. Arch Gynecol Obstet 2011;283 Suppl 1:119-120. 9. Theunissen CI, IJpma FF. Primary umbilical endometriosis: a cause of a painful umbilical nodule. J Surg Case Rep 2015;2015:rjv025. 10. Calagna G, Perino A, Chianetta D, Vinti D, Triolo MM, Rimi C, et al. Primary umbilical endometrioma: analyzing the pathogenesis of endometriosis from an unusual localization. Taiwan J Obstet Gynecol 2015;54:306-312. 11. Chikazawa K, Mitsushita J, Netsu S, Konno R. Surgical excision of umbilical endometriotic lesions with laparo- scopic pelvic observation is the way to treat umbilical endometriosis. Asian J Endosc Surg 2014;7:320-322. 12. Pariza G, Mavrodin CI. 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Primary Cutaneous Endometriosis of Umbilicus Vol. 29, No. 5, 2017 625 18. Efremidou EI, Kouklakis G, Mitrakas A, Liratzopoulos N, Polychronidis ACh. Primary umbilical endometrioma: a rare case of spontaneous abdominal wall endometriosis. Int J Gen Med 2012;5:999-1002. 19. Kesici U, Yenisolak A, Kesici S, Siviloglu C. Primary cutaneous umbilical endometriosis. Med Arch 2012; 66:353-354. 20. Bagade PV, Guirguis MM. Menstruating from the umbilicus as a rare case of primary um bilical endometriosis: a case report. J Med Case Rep 2009;3:9326. 21. Boesgaard-Kjer D, Boesgaard-Kjer D, Kjer JJ. Primary umbilical endometriosis (PUE). Eur J Obstet Gynecol Reprod Biol 2017;209:44-45. 22. Wiegratz I, Kissler S, Engels K, Strey C, Kaufmann M. Umbilical endometriosis in pregnancy without previous surgery. Fertil Steril 2008;90:199.e17-199.e20. 23. Taniguchi F, Hirakawa E, Azuma Y, Uejima C, Ashida K, Harada T. Primary umbilical endometriosis: unusual and rare clinical presentation. Case Rep Obstet Gynecol 2016;2016:9302376. 24. Chew KT, Norsaadah S, Suraya A, Hing EY, Ani Amelia Z, Nor Azlin MI, et al. Primary umbilical endometriosis successfully treated with dienogest. Horm Mol Biol Clin Investig 2017;29:67-69. 25. Claas-Quax MJ, Ooft ML, H oogwater FJ, Veersema S. Primary umbilical endometriosis. Eur J Obstet Gynecol Reprod Biol 2015;194:260-261. 26. Sidani MS, Khalil AM, Tawil AN, El-Hajj MI, Seoud MA. Primary umbilical endometriosis. Clin Exp Obstet Gynecol 2002;29:40-41. 27. Sengupta M, Naskar A, Gon S, Majumdar B. Villar's nodule. Online J Health Allied Sci 2011;10:19. 28. Kim SH, Park SJ, Lee DY, Lee ES. A case of cutaneous endometriosis. Korean J Dermatol 2002;40:100-102. 29. Song WK, Park HJ, Kim YC, Cinn YW. A case of cutaneous endometriosis. Korean J Dermatol 2000;38:999-1001. 30. Kyamidis K, Lora V, Kanitakis J. Spontaneous cutaneous umbilical endometriosis: report of a new case with immu- nohistochemical study and literature review. Dermatol Online J 2011;17:5. 31. Purvis RS, Tyring SK. Cutaneous and subcutaneous endo- metriosis. Surgical and hormonal therapy. J Dermatol Surg Oncol 1994;20:693-695.

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