{"paper_id":"65e0a353-1b40-46a6-bba8-a35f5097c527","body_text":"Running Title: Ovarian Deciduosis Mimicking Malignancy  \nVol: 02; Issue 03 (July– Sept 2026) \nJournal of Medico Informatics \n©Aayvu Publications Private Limited \n4 \n  \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n1. Introduction \nDeciduosis denotes the presence of decidual tissue in an ectopic, extra-\nendometrial location. /X_he earliest descriptions are attributed to Bayer \n(1885), who observed decidual cells at the cervix during pregnancy, and \nto Walker (1887), who documented decidual cells in the pelvic \nperitoneum in a case of ectopic pregnancy; in 1905, Hirschberg reported \na tubal pregnancy with appendiceal deciduosis that mimicked a \ngranuloma or neoplasm (Mangla  et al.  2021 ). Together, these reports \nestablished ectopic decidualization as a recognizable, if uncommon, \nbiological phenomenon that has continued to surprise clinicians and \npathologists for more than a century. Deciduosis is a benign, self-limiting \ncondition. It is hormone-dependent and is classically associated with the \nhigh circulating progesterone of pregnancy, although it may also arise on \na background of endometriosis or with exogenous or endogenous \nprogestational stimulation (Kinra  et al.  2006) . When identified in a non-\npregnant woman, an active search for an endogenous or exogenous source \nof progesterone is warranted. /X_he lesion most o/f_ten produces no \nsymptoms, but depending on its location, it can present with abdominal \npain, haemorrhage, or bowel-related complaints; rare but clinically \ndramatic presentations include potentially fatal haemoperitoneum and \nobstruction-like syndromes (McCluggage 2006) . Two principal theories \naddress its origin. /X_he first holds that ectopic decidua arises from pre-\nexisting endometriosis that decidualizes in response to the hormonal \nmilieu of pregnancy. /X_he second invokes the shared embryological \nderivation of the peritoneum and the Müllerian ducts from coelomic \nepithelium and subjacent mesenchyme; under progesterone stimulation, \npluripotent subcoelomic mesenchymal cells undergo metaplasia into \ndecidual cells. By convention, endometrial-origin lesions are termed \nendometriosis-associated decidua, whereas lesions arising through \nmesenchymal metaplasia are termed deciduosis (Kaneko  et al.  2021) . \nAlthough most reports describe pelvic peritoneal disease in pregnant \nwomen, ectopic decidua has been documented in the small bowel, \nappendix, mesentery, colon, renal pelvis, spleen, and even pelvic lymph \nnodes, where it can convincingly imitate the peritoneal spread of ovarian \ncarcinoma or peritoneal mesothelioma. Ovarian involvement is \ncomparatively uncommon. Across these sites, the recurring clinical \ndanger is the same: a benign, regressing process can be mistaken, both  \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \n \ngrossly and microscopically, for disseminated malignancy \n(Sorokin  et al.  \n2020) . /X_his diagnostic hazard has direct consequences. Intra-operative \nfrozen-section assessment of decidualized nodules is notoriously difficult, \nand an erroneous impression of carcinomatosis may trigger radical \nsurgery, adjuvant therapy, and avoidable psychological harm in an \notherwise healthy peripartum patient. Because deciduosis regresses \nspontaneously within four to six weeks postpartum, correct recognition \nspares the patient from any intervention (Kennedy  et al.  2019) . In \nparallel, pathology is undergoing a digital transformation. Whole-slide \nimaging, computational image analysis, structured synoptic reporting, \nand standardized clinical terminologies are reshaping how morphological \ndiagnoses are rendered, communicated, and reused. Rare benign mimics \nsuch as deciduosis are exactly the situations in which such tools can add \nvalue by capturing diagnostic features in machine-readable form, by \nsupporting decision-making at the point of frozen section, and by \naggregating scarce cases into shareable evidence (Masjoodi  et al.  2025) . \nWe report an unusual case of ovarian deciduosis discovered incidentally \nduring postpartum tubal ligation, use it to articulate a medico-informatics \nframework for the recognition of benign and malignant mimics. \n \n2. Materials and Methods \n2. \n1. Clinical and Surgical Material \n/X_he patient was managed in a tertiary referral centre and gave written \ninformed consent for publication of this report and the accompanying \nimages. CARE reporting guidelines were followed while preparing this \ncase report. \n \n \nReceived on : 2026-05-10 Key Words:  \nRevised on  : 2026 -06 -2 3 Ovarian deciduosis \nAccepted on  : 2026 -07 -06  Ectopic decidual reaction  \nPublished Online : 2026-07-28 Serous cystadenoma \nReview Model  : Single -Blind Review  Pregnancy \nNo. of Reviewers  : Two  Digital pathology \nEdited by  : Dr. C. Kirubhanand  Healthcare \nVol  and Issue  : 02 (0 3) Medicine \nPage No  : 04 -08   \nSimilarity  Level  : 15 % and 10% (AI)  DOI:  10.64659/jomi/224896  \nCorrespondence  : Dr. Nisha This article is licensed  \nContact Author  :                   \n \nCase Study  \nNisha Bhaskar Meshram 1  | Milind Bhatkule 1 | Vaishnavi Ujawane 1 | Saikat Mitra 1 |Shipra Sonkusare 2 | \n1.  Department of Pathology, All India Institute of Medical Sciences (AIIMS), Nagpur, Maharashtra 441108, India. \n2.  Department of Obstetrics and Gynaecology, All India Institute of Medical Sciences (AIIMS), Nagpur, Maharashtra 441108, India.  \nAbstract \nEctopic decidualization, or deciduosis, is a benign, hormone-dependent proliferation of decidual-type stromal cells outside the uterine \nendometrium. During pregnancy, it is most o/f_ten an incidental finding. Yet, its nodular gross appearance and cellular histology can closely imitate \ndisseminated malignancy, exposing patients to overtreatment when it is misread intra-operatively or on biopsy. A 34-year-old second-gravida \nwoman was admitted in active labour and had an uncomplicated full-term vaginal delivery. On the second postpartum day, during elective tubal \nligation, a 5 × 4.5 × 3 cm right ovarian cyst studded with off-white, shiny surface nodules were identified and excised together with bilateral tubal \nligation. Histology demonstrated a serous cystadenoma lined by a single layer of flattened-to-cuboidal epithelium, accompanied by surface and \nparenchymal nodules of bland, large polygonal cells with abundant eosinophilic cytoplasm consistent with decidua. Immunohistochemistry (PR \npositive, CD10 positive, focal inhibin positivity, CK20 negative) together with the absence of nuclear atypia or mitoses supported a benign decidual \nreaction. A systematic search excluded occult malignancy; a/f_ter multidisciplinary consensus, no further treatment was given, and the patient \nremained asymptomatic. We situate this case within a medico-informatics framework, proposing that whole-slide imaging with computer-aided \nimage analysis can reduce the diagnostic-error risk posed by benign mimics while generating reusable, machine-readable evidence for rare entities. \nClinician and pathologist awareness of the condition, stringent histological criteria, and digital diagnostic infrastructure together protect pregnant \npatients from unnecessary intervention.  \nISSN:  3108 -2696  (Online)  \n \n\n  \n Running Title: Ovarian Deciduosis Mimicking Malignancy  \nVol: 02; Issue 03 (July– Sept 2026) \nJournal of Medico Informatics \n©Aayvu Publications Private Limited \n5 \n2. 2. Clinical Course   \n/X_he patient was a 34-year-old woman, second gravida, admitted in active \nlabour. She underwent an uneventful full-term normal vaginal delivery \nwith episiotomy. On the second postpartum day, she underwent elective \ntubal ligation, during which a right ovarian cyst was identified \nincidentally; bilateral tubal ligation was therefore combined with right \novarian cystectomy, and the tissue was submitted for histopathology.  \n \n2. 3. Methodology  \n/X_he specimen was fixed in 10% neutral-buffered formalin, and the surgical \npathologist recorded gross parameters, including dimensions, external \nsurface characteristics, cut-surface appearance, cyst contents, wall \nthickness, and tubal measurements. Representative sections were taken \nfrom the cyst wall, the surface nodules, and the background ovary, \nprocessed routinely, embedded in paraffin, sectioned at standard \nthickness, and stained with haematoxylin and eosin. Light-microscopic \nassessment focused on the lining epithelium (stratification, papillary \narchitecture, atypia, and mitotic activity) and on the nature, distribution, \nand cytology of the nodular deposits, with particular attention to features \nthat distinguish a benign decidual reaction from a neoplastic proliferation \n(Selak  et al.  2025) . \n \n2. 4. Ancillary Studies and Diagnostic Workflow  \nImmunohistochemistry was performed on formalin-fixed, paraffin-\nembedded sections to characterize the polygonal-cell nodules and to \nexclude an epithelial malignancy. Markers done were PR, CD10, \ncytokeratin 7 (CK7), cytokeratin 20 (CK20), and inhibin; appropriate \npositive and negative controls were run in parallel. Following histological \ndiagnosis, a structured search (including whole-body PET-CT, Gastric \nendoscopy, & lower GI scopy) for occult malignancy was planned to \nconfirm the nature of the lesion, and the case was discussed with a \nmultidisciplinary team inclusive of surgical and medical gastro and \nobstetric and gynecology departments along with a medical oncologist, \nbefore a management decision of no further management needed was \nreached (Bellizzi 2020) . For this report and consistent with a medico-\ninformatics orientation, the diagnostic glass slides were digitized at 40x \nmagnification with calibrated scale bars, and the clinicopathological data \nwere abstracted into a structured, tabular format (summarized in Table \nS1)  to render the case machine-readable and reusable. /X_he \nimmunohistochemical and morphological discriminators relevant to the \ndifferential diagnosis were likewise organized into a structured matrix \n(Table S2)  suitable for incorporation into synoptic reporting templates \nand decision-support logic. No experimental intervention was performed; \nthis is a retrospective descriptive report of routine diagnostic practice \n(Eloy  et al.  2024) . \n \n \nFigure 1.  Gross photograph of the right ovarian cyst. /X_he greyish-white \nexternal surface is studded with multiple off-white, shiny, smooth-\nsurfaced elevated nodules (brown arrow) corresponding to surface \ndecidual deposits. \n \nFigure 2. Low-power photomicrograph (haematoxylin and eosin) of the \nright ovarian cyst wall and adjacent ovarian tissue, demonstrating the \noverall architecture of the lesion (scale bar = 1000 µm). /X_he image shows \novarian tissue comprising a corpus luteum (Black arrow), ovarian cyst \nwall (yellow arrow), and nodules and sheets of large polygonal cells with \nabundant eosinophilic cytoplasm and a central bland nucleus (Green \narrow) \n \n \nFigure 3. Photomicrograph (haematoxylin and eosin, ×10) showing \nnodular deposits of large polygonal cells with abundant eosinophilic \ncytoplasm and bland central nuclei (Green arrow), consistent with ectopic \ndecidua, set against congested ovarian stroma (scale bar = 200 µm). \n \nFigure 4. Higher-magnification photomicrograph (haematoxylin and \neosin) of the cyst lining and adjacent wall, showing a single attenuated \nlayer of flattened -to-cuboidal epithelium without atypia or stratification \n(scale bar = 70 µm).  \n \n3. Results \n3.\n1. Gross Findings  \n/X_he right ovarian cyst measured 5 × 4.5 × 3 cm. Its external surface was \ngreyish-white and bore multiple off-white & congested shiny, smooth-\nsurfaced, elevated nodules (Figure 1) . On sectioning, clear serous fluid \ndrained from the cyst, the inner mucosal surface was smooth, and the cyst \n\n\n  \n Running Title: Ovarian Deciduosis Mimicking Malignancy  \nVol: 02; Issue 03 (July– Sept 2026) \nJournal of Medico Informatics \n©Aayvu Publications Private Limited \n6 \nwall measured 0.4 cm in thickness. /X_he right fallopian tube measured 4.5 \ncm in length and 0.5 cm in diameter. \n \n3.2. Microscopic Findings  \n/X_he cyst was lined by a single layer of flattened-to-cuboidal epithelium \nwithout stratification, multilayering, or papillary formation, and without \nborderline change, nuclear atypia, or features of malignancy, appearances \nconsistent with a serous cystadenoma (Figures 2 and 4) . /X_he surrounding \nwall showed normal ovarian stroma containing a corpus luteum and \nfollicular cysts. Within and on the surface of the ovary were numerous \nnodular deposits of large polygonal cells with abundant pale-to-\neosinophilic cytoplasm and central, bland nuclei; the deposits were \ncongested and morphologically resembled decidual tissue (Figure 3) . \n \n3.3. Immunohistochemistry and Final Diagnosis  \n/X_he large polygonal cells were positive for PR (progesterone receptor), \nCD10 and CK7, showed focal cytoplasmic positivity for inhibin, and were \nnegative for CK20. For PR, the cells showed diffuse, strong nuclear \npositivity, while for CD10, cells showed consistent and diffuse cytoplasmic \npositivity. CK7 showed focal cytoplasmic positivity in the large cells. PR \npositivity supports progesterone-driven decidual differentiation, while \nCD10 positivity favors endometrial stromal/decidual stromal lineage. \nCK20 negativity is useful in excluding metastatic gastrointestinal \nadenocarcinoma, particularly signet-ring cell carcinoma/Krukenberg \ntumour. Although CK7 positivity was observed, this was interpreted \ncautiously in view of the bland cytomorphology and ab sence of \ndestructive epithelial malignancy; the possibility of entrapped \nMüllerian/ovarian surface epithelial elements or focal nonspecific staining \nshould be considered depending on the staining distribution. Focal \ninhibin positivity may reflect associated luteinized stromal change and, in \nthe absence of diffuse inhibin expression or convincing sex-cord stromal \nmorphology, does not exclude deciduosis. Overall, the bland morphology, \ncomplete absence of mitoses, immunoprofile, and pregnancy-associated \nclinical context together favor ovarian surface deciduosis rather than \nmetastatic signet-ring cell carcinoma or a primary ovarian epithelial \nmalignancy. A final diagnosis of right ovarian serous cystadenoma with \novarian deciduosis was rendered. /X_he clinicopathological findings are \nsummarized in Table S1 , and the morphological and \nimmunohistochemical discriminators from the principal mimics are \npresented in Table S2.  /X_he differential diagnosis of ovarian deciduosis \nincludes several pregnancy-associated and hormonally influenced lesions. \nDecidualized endometriosis is one of the closest mimics, particularly \nwhen endometriotic stromal cells undergo prominent decidual change \nduring pregnancy or progesterone exposure. /X_he presence of \nendometrial-type glands, endometriotic cyst lining, hemorrhage, \nhemosiderin-laden macrophages, or residual endometrial-type stroma \nfavors decidualized endometriosis rather than isolated deciduosis. In our \ncase, there was no evidence of hemorrhage, hemosideri n-laden \nmacrophages, or glands, previous indicative history; which ruled out the \npossibility of decidualized endometriosis. Luteinized stromal \nproliferations may also enter the differential diagnosis, as they may show \nlarge polygonal cells with abundant eosinophilic or lipid-rich cytoplasm. \nHowever, these lesions are usually composed of luteinized sex-cord \nstromal cells and may show positivity for inhibin, calretinin, or SF-1, \nwhereas deciduosis demonstrates decidual stromal differentiation. In our \ncase, inhibin showed only focal positivity. A particularly important \nmalignant mimic is metastatic signet-ring cell carcinoma involving the \novary. /X_his is clinically significant because decidual cells may appear \nvacuolated and can simulate signet-ring morphology. However, metastatic \nsignet-ring cell carcinoma usually shows infiltrative malignant epithelial \ncells with intracellular mucin, nuclear atypia, mitotic activity, \ndesmoplastic stromal response, and cytokeratin positivity, o/f_ten with \ngastrointestinal marker expression depending on the primary site. In our \ncase, CK7 was only focally positive, and CK20 was negative, excluding the \npossibility of metastatic signet ring carcinoma. In contrast, deciduosis \nshows bland polygonal decidual cells, abundant eosinophilic or \nvacuolated cytoplasm, absence of destructive invasion, absence of \nsignificant mitotic activity, and lack of epithelial/mucinous differentiation. \n/X_herefore, correlation with pregnancy or hormonal status, careful \nhistomorphological assessment, and a targeted immunohistochemical \npanel are essential to avoid overdiagnosis of malignancy. \n \n3.4. Management and Outcome  \nA subsequent systematic investigation including whole body PET-CT, \ngastric endoscopy & lower GI scopy was planned to exclude potential sites \nof occult malignancy; however, a/f_ter the final histopathological diagnosis \nand immunohistochemical findings supported ovarian deciduosis, these \ninvestigations were deferred. No follow-up imaging was performed to \ndocument radiological regression. Serum tumour markers assessed \nduring the immediate post-surgery period were within normal limits: \nCEA: 1.95 ng/ml, CA 19-9: 27.04 U/ml, and CA-125: 12.07 units/ml. /X_he \npatient also started having regular menses two months a/f_ter surgery. /X_he \npatient had no gastrointestinal symptoms, and an opinion from both the \nmedical gastroenterologist and gastrosurgeon was obtained, who advised \nthat no active management was required from their side. /X_he patient has \nbeen under ongoing follow-up for the last one year and remains \nasymptomatic. \n \n4. Hypothesis of the Study \n/X_his report advances two complementary sets of hypotheses, one \nbiological and one informatic, both centred on the recurring problem of a \nbenign, regressing lesion being mistaken for malignancy. \n4.1. Biological hypotheses \nWe hypothesize that the ovarian nodules in this patient arose through \nprogesterone-driven decidual transformation and that two mechanisms \ncan account for such lesions. /X_he endometriosis-derived hypothesis \nproposes that pre-existing ectopic endometrial stroma decidualized in \nresponse to the gestational hormonal surge; the subcoelomic-metaplasia \nhypothesis proposes that pluripotent mesenchymal cells beneath the \novarian surface epithelium, sharing a coelomic origin with the Müllerian \nsystem, transformed directly into decidual cells under progesterone \nstimulation. /X_he presence of surface and subserosal deposits over a \nbackground of normal ovarian stroma, without identifiable endometriotic \nglands, is more consistent with the metaplastic pathway in this case, \nalthough the two mechanisms are not mutually exclusive. A corollary \ntestable prediction is that such lesions should regress within four to six \nweeks of delivery as progesterone falls, an expectation that, if confirmed \non interval imaging or follow-up, would itself argue strongly against \nmalignancy and against any therapeutic intervention.  \n4.2. Informatic hypotheses \n/X_he central informatic hypothesis is that the diagnostic-error risk posed \nby benign mimics is reducible through digital pathology infrastructure \nrather than through expanded surgery. Specifically, we hypothesize: (i) \nthat whole-slide images of decidualized nodules carry quantifiable \nmorphometric and texture signatures, uniform nuclear size, low nuclear-\nto-cytoplasmic ratio, absent mitotic figures, abundant eosinophilic \ncytoplasm, that a computer-aided classifier can use to discriminate \ndecidua from serous carcinoma, mesothelioma, and metastatic carcinoma \nwith high negative predictive value; (ii) that encoding the discriminators \nin Table S2  as explicit decision-support logic within a synoptic reporting \ntemplate will lower the rate of misclassification at intra-operative frozen \nsection, where time pressure and sampling limitations are greatest; and \n(iii) that aggregating rare cases such as this one into a unified, \n\n  \n Running Title: Ovarian Deciduosis Mimicking Malignancy  \nVol: 02; Issue 03 (July– Sept 2026) \nJournal of Medico Informatics \n©Aayvu Publications Private Limited \n7 \nstandardized registry will supply the labelled data that single institutions \ncannot accumulate, thereby making robust models for uncommon benign \nentities feasible. \n \n5. Medico-Informatics Perspective \nDigitizing the diagnostic slides, as was done here, converts a perishable \nglass artefact into a durable, shareable, and computable object. For a rare \nmimic such as deciduosis, whole-slide imaging permits immediate second \nopinion, preserves the exact field on which the diagnosis rested, and \nprovides the substrate for quantitative analysis. Calibrated scale bars \n(1000, 200, and 70 µm in Figures 2–4) anchor measurements that are \notherwise subjective at the microscope.  In a digital pathology-based \napproach, useful image-analysis features for ovarian deciduosis would \ninclude nuclear size and shape, nuclear size variation, nuclear-to-\ncytoplasmic ratio, chromatin texture, and mitotic activity. /X_he \nmorphology of decidua is, in computational terms, highly regular. \nDecidual cells usually show large polygonal cells with abundant \ncytoplasm, monomorphic bland nuclei, low nuclear-to-cytoplasmic ratio, \nsmooth chromatin, and absent or rare mitoses. /X_hese are the features that \nmorphometric and deep-learning classifiers can use, suggesting that a \nbenign-versus-malignant triage model could identify decidua-like \nnodules for conservative confirmation rather than radical action. In \ncontrast, malignant mimics are more likely to show marked nuclear \npleomorphism, irregular nuclear contours, increased nuclear-to-\ncytoplasmic ratio, coarse chromatin, increased mitotic activity, atypical \nmitoses, necrosis, and infiltrative growth. /X_hus, digital image analysis may \nhelp highlight benign decidual morphology, but such tools should be best \nused as a safety net that increases negative predictive value, not as an \nautonomous diagnostician, and the final diagnosis should still rely on \nroutine histology, clinical correlation, and immunohistochemistry. /X_he \nfindings in Table S1 and the key distinguishing features in Table S2 can \nbe recorded in a structured format rather than as free text alone. If these \nfields are linked to standard medical terminologies such as SNOMED CT \nand ICD-O, the diagnosis becomes easier to search, compare, share, and \naudit across different systems. /X_his approach can also support automated \nquality checks. For example, if a peripartum patient has ovarian surface \nnodules but the cells show no atypia and no mitotic activity, the system \ncould prompt the pathologist to consider a benign pregnancy-related \nlesion such as deciduosis before diagnosing malignancy. /X_his would be of \ngreat help while reporting such cases at the frozen section. Sharing \ndigitized slides and structured pathology reports in a standard format can \nmake expert consultation easier and faster, especially when the diagnosis \nis rare or difficult. It would also help create shared registries of uncommon \nbenign mimics such as deciduosis. /X_his is important because a single \ncentre may see very few cases of ovarian deciduosis, making it difficult to \nbuild experience or train digital pathology models. By safely pooling cases \nfrom multiple centres while protecting patient privacy, larger and more \nuseful datasets can be created. /X_he same system can also help with follow-\nup. For example, if deciduosis is expected to regress a/f_ter pregnancy, later \nclinical or imaging findings can be added to the record. /X_his follow-up \ninformation can then support the original benign diagnosis and help \nimprove future diagnostic confidence. /X_hese advantages will be useful \nonly if digital pathology tools are used carefully and responsibly. A model \ntrained mainly on common cancers may wrongly suspect malignancy \nwhen it sees a rare benign condition such as deciduosis. Limited case \nnumbers, poor-quality annotations, and differences between slides from \ndifferent centres can also affect the reliability of the results. /X_herefore, the \noutput of any algorithm should be used only as a supportive aid, not as a \nfinal diagnosis. /X_he final interpretation must remain with the pathologist. \nBefore such tools are used in clinical practice, they should be properly \nvalidated, regularly audited, and used with clear responsibility and \naccountability. \n \n6. Conclusion \nOvarian deciduosis is a benign, hormone-driven, self-limiting condition \nthat is usually encountered during pregnancy or the peripartum period. \nIts clinical significance lies in its ability to mimic malignancy. Gross \nnodularity and prominent decidual cells may raise concern for \ncarcinomatosis, metastatic carcinoma, or mesothelioma, potentially \nleading to unnecessary radical surgery or adjuvant therapy. Accurate \ndiagnosis requires careful attention to the clinical setting, bland cytology, \nabsence of mitotic activity, lack of destructive invasion, and a supportive \nimmunohistochemical profile. Correct recognition of this entity can \ntherefore convert a worrying intraoperative impression into a benign \ndiagnosis requiring no active treatment. /X_his case also demonstrates how \ndigital pathology and medical informatics may strengthen diagnostic \nsafety. Whole-slide imaging, structured reporting, standardized \nterminology, computer-assisted analysis, decision-support tools, and \nshared registries can all help improve recognition of rare benign mimics \nsuch as deciduosis. /X_hese systems are not a substitute for expert pathology \nreview, but they can provide an additional safeguard against premature or \nirreversible treatment decisions. Greater awareness of ovarian deciduosis \namong clinicians and pathologists, supported by responsible digital \npathology infrastructure and human-supervised decision support, may \nhelp prevent overtreatment in pregnant and peripartum patients. \n \n \n7. Disclosure Statements \n7.\n1. Author Contribution \nNBM:  Conceptualization, research design, and final approval of the \nmanuscript. MB:  Data analysis and interpretation, critical revision of the \nmanuscript. VU:  Data collection, data curation, and data analysis. SM:  \nData analysis and interpretation. SS:  Clinical data collection and patient \nmanagement. All authors reviewed the manuscript, and the \ncorresponding author has read and approved the final version of the \nmanuscript. \n \n7.2. Declaration of Generative AI \nDuring the preparation of this manuscript, the authors used Grammarly \nand QuillBot solely for grammar correction, language editing, and \nimprovement of sentence clarity. /X_hese tools were not used to generate \nscientific content, analyze data, interpret results, or formulate conclusions. \n/X_he authors carefully reviewed and edited all changes and take full \nresponsibility for the accuracy, originality, and integrity of the manuscript. \n \n7.3. Ethics approval (for clinical/animal studies) \nInstitutional Ethics Committee approval was not required for this \nanonymized single-patient case report in accordance with institutional \npolicy. /X_he manuscript has been prepared in accordance with the ethical \nprinciples of the Declaration of Helsinki. Written informed consent for \npublication was obtained from the patient. \n \n7.4. Informed Consent Statement \nWritten informed consent was obtained from the patient for publication \nof this case report and any accompanying images. All identifying \ninformation has been removed to protect the patient's privacy. \n \n7.5. Data Availability Statement \nAll data generated or analyzed during this study are included in this \npublished article. Additional information is available from the \ncorresponding author upon reasonable request, subject to patient \nconfidentiality and institutional policies. \n \n7.6. Acknowledgment \n/X_he authors sincerely thank the Department of Pathology and the \nDepartment of Obstetrics & Gynecology, All India Institute of Medical \n\n  \n Running Title: Ovarian Deciduosis Mimicking Malignancy  \nVol: 02; Issue 03 (July– Sept 2026) \nJournal of Medico Informatics \n©Aayvu Publications Private Limited \n8 \nSciences (AIIMS), Nagpur, for their support in the diagnosis, clinical \nmanagement, and preparation of this case report. /X_he authors also \nacknowledge the patient for providing informed consent for publication. \n \n7.7. Funding Statement \n/X_his research received no external funding. All work was conducted using \ninstitutional resources without dedicated grant support. \n \n7.8. Conflicts of Interest \n/X_he authors declare that they have no known financial, personal, \nacademic, or other relationships that could inappropriately influence, or \nbe perceived to influence, the work reported in this manuscript. /X_he \nauthors confirm that there are no competing interests to declare.  \n \n7.9. Corresponding Author Contact Information \n/X_he corresponding author Dr. Nisha Bhaskar Meshram can be contacted \nvia email drnisha[at]aiimsnagpur.edu.in . \n \n7.10 . Supplementary Information \nSupplementary material for this article is availabl e at \nhttps://jomi.aayvu.com/SuppFile/224896/1/   . \n \n7.11 . ORcID Information \nNisha Bhaskar Meshram 0000-0001-6949-6399 \nMilind Bhatkule 0000-0003-2014-264X \nVaishnavi Ujawane 0000-0002-6763-5575  \nSaikat Mitra 0000-0002-0208-3108  \nShipra Sonkusare 0000-0002-3659-8708  \n \n7.\n12 . Handling Editor Information \n/X_his manuscript was handled and edited by Dr. Kirubhanand \nChandrasekaran , Additional Professor, Department of Anatomy, All \nIndia Institute of Medical Sciences (AIIMS), Nagpur, Maharashtra, India. \nEditor contact email:  jomi[at]aayvu.com \n \n8. Reference \nBellizzi  AM. (2020), An Algorithmic Immunohistochemical Approach to \nDefine Tumor Type and Assign Site of Origin, Adv Anat Pathol,  \n27(3):114-163. doi: 10.1097/PAP.0000000000000256. PMID:  \n32205473. \nEloy  C, Seegers P, Bazyleva E, Fraggetta F. (2024), /X_he 1 million words \npathology report or the challenge of a reproducible and meaningful \nmessage, ESMO Real World Data Digit Oncol,  4:100044. \ndoi: 10.1016/j.esmorw.2024.100044. PMID:  41647787. \nKaneko  M, Nozawa H, Rokutan H, Murono K, Ushiku T, Ishihara S. (2021), \nEctopic decidua of the appendix: a case report, Surg Case Rep,  \n7(1):117. doi: 10.1186/s40792-021-01204-9. 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(2020), \nDiffuse Ectopic Deciduosis Imitating Peritoneal Carcinomatosis \nwith Acute Abdomen Presentation: A Case Report and Literature \nReview, Case Rep Obstet Gynecol,  2020:8847082. \ndoi: 10.1155/2020/8847082. PMID:  33062356. \n \nLanguage Policy from Publisher: /X_he publisher, editors, and reviewers are \nnot responsible for the accuracy, completeness, or appropriateness of the language, \ngrammar, spelling, or style used in this article. /X_he content, including all linguistic \nand stylistic elements, is the sole responsibility of the authors. 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Journal of Medico Informatics, 02(03), 04– 08. doi:  \nhttp://doi.org/10.64659/jomi/224896  \n \n41","source_license":"CC0","license_restricted":false}