Malignant mesonephric tumors of the female genital tract: a clinicopathologic study of 9 cases

Carbon ion radiotherapy for mesonephric adenocarcinoma of the uterine cervix: a case report

BACKGROUND

Mesonephric adenocarcinoma is an extremely rare subtype of uterine cervical cancer that is associated with a poor prognosis and for which a standardized treatment protocol has not been established. Carbon ion radiotherapy (CIRT) is an emerging radiotherapy modality that has been shown to have a favorable anti-tumor effect, even for tumors resistant to conventional photon radiotherapy or chemotherapy. However, there is no report on CIRT outcomes for mesonephric adenocarcinoma of the uterine cervix.

CASE PRESENTATION

We treated a 47-year-old Japanese woman with mesonephric adenocarcinoma of the uterine cervix (T2bN0M0 and stage IIB according to the 7th edition of the Union for International Cancer Control and International Federation of Gynecology and Obstetrics, respectively) with CIRT combined with brachytherapy and concurrent chemotherapy. CIRT consisted of whole pelvic irradiation and boost irradiation to the gross tumor; 36.0 Gy (relative biological effectiveness [RBE]) in 12 fractions and 19.2 Gy (RBE) in 4 fractions, respectively, performed once a day, four times per week. Computed tomography-based image-guided adaptive brachytherapy was performed after completion of CIRT, for which the D90 (i.e., the dose prescribed to 90% of the target volume) for the high-risk clinical target volume was 20.4 Gy in a total of 3 sessions in 2 weeks. A weekly cisplatin (40 mg/m2) dose was administered concomitantly with the radiotherapy for a total of five courses. From 4 months post-CIRT, the patient developed metastasis of the lung, with a total of 10 lung metastases over 70 months; these lesions were treated on each occasion by photon stereotactic body radiotherapy and/or systemic therapy. At 8 years from initial treatment (i.e., 2 years after the last treatment), the patient is alive without any evidence of recurrence and maintains a high quality of life.

CONCLUSIONS

This is the first report of CIRT for treatment of mesonephric adenocarcinoma of the uterine cervix. The present case indicates the potential efficacy of CIRT in combination with brachytherapy for treatment of this disease.

Mesonephric and mesonephric-like adenocarcinomas of gynecologic origin: A single-center experience with molecular characterization, treatment, and oncologic outcomes

OBJECTIVES

Mesonephric (MA) and mesonephric-like (MLA) adenocarcinomas are rare cancers, and data on clinical behavior and response to therapy are limited. We sought to report molecular features, treatment, and outcomes of MA/MLA from a single institution.

METHODS

Patients with MA (cervix) or MLA (uterus, ovary, other) treated at Memorial Sloan Kettering Cancer Center (MSK) from 1/2008-12/2021 underwent pathologic re-review. For patients with initial treatment at MSK, progression-free survival (PFS1) was calculated as time from initial surgery to progression or death; second PFS (PFS2) was calculated as time from start of treatment for recurrence to subsequent progression or death. Overall survival (OS) was calculated for all patients. Images were retrospectively reviewed to determine treatment response. Somatic genetic alterations were assessed by clinical tumor-normal sequencing (MSK-Integrated Mutation Profiling of Actionable Cancer Targets [MSK-IMPACT]).

RESULTS

Of 81 patients with confirmed gynecologic MA/MLA, 36 received initial treatment at MSK. Sites of origin included cervix (n = 9, 11%), uterus (n = 42, 52%), ovary (n = 28, 35%), and other (n = 2, 2%). Of the 36 patients who received initial treatment at MSK, 20 (56%) recurred; median PFS1 was 33 months (95% CI: 17-not evaluable), median PFS2 was 8.3 months (95% CI: 6.9-14), and median OS was 87 months (95% CI: 58.2-not evaluable). Twenty-six of the 36 patients underwent MSK-IMPACT testing, and 25 (96%) harbored MAPK pathway alterations.

CONCLUSION

Most patients diagnosed with early-stage disease ultimately recurred. Somatic MAPK signaling pathway mutations appear to be highly prevalent in MA/MLA, and therapeutics that target this pathway are worthy of further study.

Ever Expanding Morphologic Patterns of Mesonephric-like Adenocarcinomas of the Uterine Corpus: A Report of Two Tumors and a Brief Review of the Literature

Mesonephric-like adenocarcinoma (MLA) of the endometrium shows a variety of morphologic appearances, including small glands, tubules with eosinophilic materials in the lumen, prominent papillary patterns, spindled cells, solid formations, and corded and hyalinized patterns. Unique morphology, characteristic immunohistochemical staining patterns, molecular alterations, and awareness of the pathologists make it possible to identify this tumor accurately. This report of two additional morphologic patterns, intestinal goblet cells mimicking intestinal-type mucinous carcinoma and squamous differentiation with spindle and epithelioid cells mimicking carcinosarcoma of the endometrium will expand the literature on MLA.

Diagnosis, Treatment and Prognosis of Mesonephric Adenocarcinoma of the Vagina: A Literature Review and a Case Report

BACKGROUND

Mesonephric adenocarcinoma (MA) of the vagina is a rare tumor that arises from mesonephric remnants (Wolffian) in the female genital tract. It is a neoplasm with no significant evidence about its diagnosis, treatment, follow-up and prognosis.

METHODS

Systematic research of the literature was conducted in Scopus, PubMed/MEDLINE, ScienceDirect and the Cochrane Library, including observational prospective and retrospective studies, case series and case reports. We collected data regarding studies related to diagnosis and treatment options evaluating the following aspects: study design, population, treatment type, rate of surgical complications and fertility outcome. We further included a case report of laparoscopic management of MA with pictorial assays.

RESULTS

Thirteen cases of MA of the vagina are available in the literature, including our case report. The median age at diagnosis was 52 years old; the majority of patients reported vaginal bleeding as a symptom (38%); and ultrasound, followed by a magnetic resonance and CT scan were the diagnostic tools most used. In 54% of the cases, a surgical biopsy was performed, and 92% of the patients underwent upfront surgery with an open access or vaginal resection except one case fully managed by minimally invasive surgery. Most of the patients (68%) received adjuvant treatment with chemotherapy or radiotherapy or a combination of them. The mean follow-up period was 6 years.

CONCLUSIONS

Despite the rarity of this cancer and bizarre location, a minimally invasive approach seems feasible after multidisciplinary evaluation. According to the rarity of this tumor, any future case and follow-up data must be reported in the literature in order to enlarge the knowledge about it.

Androgen receptor amplification in mesonephric remnants

Mesonephric remnants (MRs) are embryonic vestiges most commonly found in female pathology specimens from the lateral wall of the cervix. The highly regulated genetic programme of mesonephric duct development has been well characterised in animals based on traditional surgical castration and knockout mouse experiments. However, the process is incompletely understood in humans. MRs are believed to give rise to mesonephric neoplasms, which are rare tumours with uncertain pathophysiology. There is a dearth of molecular studies on mesonephric neoplasms in part due to their rarity. Here, we report the results of next-generation sequencing of MR, which identified amplification of the androgen receptor gene for the first time to the best of our knowledge and discuss the potential implications in the context of the literature.

Ovarian Combined Serous Borderline Tumor/Low-grade Serous Carcinoma and Mesonephric-like Lesion: Report of 2 Cases With New Observations

Ovarian combined serous borderline tumor/low-grade serous carcinomas (SBT/LGSC) and mesonephric-like adenocarcinomas (MLA) have been previously reported and the presence of identical oncogenic somatic mutations in both components supports the concept that at least some of MLAs arise from a Müllerian origin. We report 2 cases of ovarian combined SBT/LGSC and mesonephric-like lesion. Case 1 was a 70-yr-old woman presented with a liver lesion and omental carcinomatosis. Histologic examination revealed biphasic tumors in bilateral ovaries consisting of conventional SBT and invasive MLA with extraovarian spread. The right ovary also had a component of cribriform variant of SBT/noninvasive LGSC. The SBT/LGSC component was diffusely positive for Pax8, WT-1, and ER, focally positive for PR, and negative for GATA3, while the MLA component was diffusely positive for GATA3 but negative for WT-1, ER, and PR. Molecular analysis revealed a KRAS G12V mutation in both the SBT/LGSC and MLA components, indicating their clonal origin. Case 2 was a 58-yr-old woman who presented with conventional type SBT in both ovaries. In addition, the left ovarian tumor demonstrated a few areas (each <5 mm) of mesonephric-like differentiation/hyperplasia in close proximity to the serous-type epithelium, with an immunophenotype of focal GATA3 expression, luminal pattern of CD10 staining and negative WT-1, ER, and PR staining. This phenomenon has been reported in endometrioid borderline tumor but not in any serous type lesions. The findings in case 1 provide further evidence to demonstrate the clonal relationship between these morphologically and immunophenotypically distinct components. It also supports the theory that, unlike cervical mesonephric carcinomas originating from mesonephric remnants, MLAs are derived from a Müllerian-type lesion with differentiation into mesonephric lineage. The presence of a hyperplastic mesonephric-like lesion/differentiation in case 2 indicates that a precursor lesion in the same lineage with the potential to develop into MLA exists in the ovary.

Mesonephric-like Carcinosarcoma of the Uterine Corpus: Clinicopathological, Molecular and Prognostic Characteristics in Comparison With Uterine Mesonephric-like Adenocarcinoma and Conventional Endometrial Carcinosarcoma

BACKGROUND/AIM

This study aimed to investigate the clinicopathological, prognostic and molecular characteristics of uterine mesonephric-like carcinosarcoma (MLCS).

PATIENTS AND METHODS

We collected clinical, pathological, and genetic information from 12 MLCS patients, and analyzed their differences from mesonephric-like adenocarcinoma (MLA) and conventional endometrial carcinosarcoma (CECS).

RESULTS

The epithelial component was exclusively MLA in all MLCS cases. Metastatic and recurrent tumors consisted predominantly or exclusively of MLA in the majority of MLCS cases. Patients with MLCS and MLA presented with more advanced-stage disease than those with CECS. They also exhibited post-treatment recurrence and lung metastases more frequently than CECS. Disease-free survival rates of MLCS and MLA were shorter than those of CECS. Tumor protein 53 gene mutations were detected in four MLCS cases.

CONCLUSION

The predominance or exclusive presence of MLA in metastatic and recurrent tumors highlights the possibility that MLA may determine the clinical outcomes of patients with MLCS. Further studies are required to provide direct molecular evidence of the monoclonal origin of uterine MLCS.

Mesonephric-like Adenocarcinoma of the Female Genital Tract: From Morphologic Observations to a Well-characterized Carcinoma With Aggressive Clinical Behavior

Mesonephric-like adenocarcinoma (MLA) was introduced as a new tumor type in the endometrium and the ovary in the 2020 World Health Organization (WHO) Classification. This is a rare recently described (2016) and clinically aggressive carcinoma with a propensity for distant spread, especially to the lungs. MLA has a characteristic morphology and immunophenotype (hormone receptor negative; TTF1 and/or GATA3 positive). These neoplasms are commonly associated with KRAS and PIK3CA mutations and in the Cancer Genome Atlas (TCGA) molecular classification of endometrial carcinomas fall into the copy number low/no specific molecular profile category. Although they show significant morphological, immunophenotypic and molecular overlap with cervical mesonephric adenocarcinomas, there are other parameters which suggest a Mullerian origin and, as such, the term MLA seems apt. MLA can be added to the list of endometriosis-associated ovarian neoplasms. In this paper, I outline the series of events which lead to the first description of MLA and review the subsequent literature on this tumor type which has expanded on the morphologic features and immunophenotype, discovered the molecular underpinnings and elucidated the clinical behavior. The discovery of MLA represents an example of "new" entities still to this day being discovered through careful morphologic observations and referral of cases for specialist opinion.

Endometrial Mesonephric-like Adenocarcinoma Presenting as an Ocular Lesion: A Case Report

Endometrial mesonephric-like carcinoma (ML-CA) is a recently recognized subtype of aggressive endometrial adenocarcinoma that is morphologically and immunophenotypically similar to mesonephric carcinoma but not typically associated with mesonephric remnants. Here, we report a case of 58-yr-old female who had a past medical history of fibroids and of irregular menstrual bleeding for ~20 yr who presented with visual disturbance. On further investigation, she was found to have a large choroidal peri-papillary tumor of the right eye. A presumptive diagnosis of choroidal melanoma was made. Right eye enucleation was performed, and microscopy revealed moderately differentiated metastatic adenocarcinoma. Further work up was advised. A uterine mass was identified on imaging followed by endometrial biopsy that showed a morphologically and immunohistochemically similar tumor to that in the eye. A hysterectomy was carried out and a malignant neoplasm with varying morphologic patterns including gland formation, solid sheets of tumor cells, cribriform, glomeruloid, spindled and papillary areas was seen. The immunohistochemical profile showed diffuse strong positivity for AE1/AE3, TTF1, P16, and vimentin. CD56, GATA3, Napsin A, and CD10 were focally positive. The neoplastic cells were negative for the following markers ER, PR, WT1, calretinin, and synaptophysin. PDL-1 was negative and mismatch repair protein was proficient. An identical KRAS mutation was detected in both the uterine corpus and ocular tumors. The findings are in keeping with a uterine mesonephric-like adenocarcinoma with an ocular metastasis. An Oncomine Focus-Mutation profile, Thermo-Fisher Scientific Inc., a 60 gene oncologic panel, performed on the ocular tumor, revealed no further mutations.

Cervical Carcinosarcoma: Current Understanding on Pathogenesis, Diagnosis, Management and Future Perspectives

Cervical carcinosarcoma (CCS) is a rare aggressive tumor which was referred to as a sarcoma initially with its morbidity less than 1% of all cervical cancers. Four theories have been proposed for the pathogenesis of CCS. The “metaplastic theory,” also called “monoclonal theory,” has been widely accepted so far. The most common clinical symptom of CCS is abnormal vaginal bleeding. CCS is much less common than the counterparts in uterine corpus and usually confused with uterine carcinosarcoma (UCS) or common cervical cancer. The management for CCS has been mainly extrapolated from studies of UCS or cervical cancers. However, CCS has its special anatomical position and biological behaviors and is usually diagnosed at an early stage than UCS. Currently, there is no consensus on the survival, management and prognosis factors of CCS. We reviewed and summarized the literatures regarding to the epidemiology, clinical presentations, pathogenesis, diagnosis and treatment of CCS for providing clinicians with comprehensive information to diagnose and treat this malignancy.

Mesonephric Adenocarcinoma of the Vagina Harboring TP53 Mutation

Mesonephric adenocarcinoma (MA) of the female genital tract is a rare but distinct entity, exhibiting unique morphological, immunophenotypical, and molecular characteristics. Vaginal MA is hypothesized to arise from the mesonephric remnants located in the lateral vaginal wall. A 52-year-old woman presented with vaginal bleeding. Physical examination revealed a protruding mass in the left vaginal wall. Pelvic magnetic resonance imaging revealed a 2.5-cm mass arising from the left upper vagina and extending posterolaterally to the extravaginal tissue. The punch biopsy was diagnosed as poorly differentiated adenocarcinoma. She received radical surgical resection. Histologically, the tumor displayed various architectural patterns, including compactly aggregated small tubules, solid cellular sheets, endometrioid-like glands and ducts, intraluminal micropapillae, cribriform structure, and small angulated glands accompanied by prominent desmoplastic stroma. The tubules and ducts possessed hyaline-like, densely eosinophilic intraluminal secretions. The tumor extended to the subvaginal soft tissue and had substantial perineural invasion. Immunostaining revealed positivity for the mesonephric markers, including GATA3, TTF1, and PAX2, while showing very focal and weak positivity for estrogen receptor and negativity for progesterone receptor. Additionally, we observed a complete absence of p53 immunoreactivity. Targeted sequencing analysis revealed that the tumor harbored both activating KRAS p.G12D mutation and truncating TP53 p.E286* mutation. A thorough review of the previous literature revealed that 4.5% (3/67) of vaginal/cervical MAs and 0.9% (1/112) of uterine/ovarian mesonephric-like adenocarcinomas harbor TP53 mutations, indicating that this is very uncommon in malignant mesonephric lesions. In summary, we presented a rare case of vaginal MA uniquely harboring pathogenic TP53 mutation, resulting in p53 aberration.

Napsin-A and AMACR are Superior to HNF-1β in Distinguishing Between Mesonephric Carcinomas and Clear Cell Carcinomas of the Gynecologic Tract

Mesonephric carcinoma is a rare gynecologic neoplasm commonly mistaken for clear cell carcinoma, because of their overlapping morphologic features. Both tumors are negative for estrogen receptor and p16, magnifying this diagnostic dilemma. Recently, hepatocyte nuclear factor-1 beta (HNF-1β), a marker for clear cell carcinoma, has also been shown to be positive in mesonephric carcinomas. Other more recent markers for clear cell carcinoma, however, such as Napsin-A and alpha-methylacyl-CoA racemase (AMACR), have not yet been studied in mesonephric carcinomas. Here we examine HNF-1β, AMACR, and Napsin-A immunohistochemistry in 18 mesonephric and 55 endometrial/cervical clear cell carcinomas. HNF-1β was considered positive if nuclear staining was present in ≥70% of cells and at least moderate intensity; for Napsin-A and AMACR, any cytoplasmic staining was considered positive (≥1%). H-scores were determined by multiplying the intensity score by proportion score. HNF-1β was positive in a substantial portion of mesonephric carcinomas (9/18, 50%; H-score 98) and clear cell carcinomas (34/55, 62%; H-score 163) and did not distinguish between the 2 entities (specificity, 50%; P-value of H-score=0.08). Napsin-A and AMACR expression was significantly higher in clear cell [43/55 (78%) and 41/55 (75%), respectively] than mesonephric carcinomas [4/18 (22%) and 4/18 (22%) respectively], and helpful in this differential (specificity: 78% and 78%; P<0.05 for both). When Napsin-A and AMACR staining were seen in mesonephric carcinomas, staining was focal (≤5%), whereas staining in clear cell carcinomas was patchy/diffuse. In summary, Napsin-A and AMACR are helpful in distinguishing mesonephric carcinomas from clear cell carcinomas of the female genital tract, but HNF-1β is not.

Mesonephric and mesonephric-like carcinomas of the female genital tract: molecular characterization including cases with mixed histology and matched metastases

Mesonephric carcinoma of the cervix is a rare tumor derived from Wolffian remnants. Mesonephric-like carcinomas of the ovary and endometrium, while morphologically similar, do not have obvious Wolffian derivation. Here, we sought to characterize the repertoire of genetic alterations in primary mesonephric and mesonephric-like carcinomas, in the distinct histologic components of mixed cases, as well as in matched primary tumors and metastases. DNA from microdissected tumor and normal tissue from mesonephric carcinomas (cervix, n = 8) and mesonephric-like carcinomas (ovarian n = 15, endometrial n = 13) were subjected to sequencing targeting 468 cancer-related genes. The histologically distinct components of four cases with mixed histology and four primary tumors and their matched metastases were microdissected and analyzed separately. Mesonephric-like carcinomas were underpinned by somatic KRAS mutations (25/28, 89%) akin to mesonephric carcinomas (8/8, 100%), but also harbored genetic alterations more frequently reported in Müllerian tumors. Mesonephric-like carcinomas that lacked KRAS mutations harbored NRAS (n = 2, ovary) or BRAF (n = 1, endometrium) hotspot mutations. PIK3CA mutations were identified in both mesonephric-like (8/28, 28%) and mesonephric carcinomas (2/8, 25%). Only mesonephric-like tumors harbored CTNNB1 hotspot (4/28, 14%) and PTEN (3/13, 23%) mutations. Copy number analysis revealed frequent gains of chromosomes 1q and 10 in both mesonephric (87% 1q; 50% chromosome 10) and mesonephric-like tumors (89% 1q; 43% chromosome 10). Chromosome 12 gains were more frequent in ovarian mesonephric-like carcinomas, and losses of chromosome 9 were more frequent in mesonephric than in mesonephric-like carcinomas (both p = 0.01, Fisher's exact test). The histologically distinct components of four mixed cases were molecularly related and shared similar patterns of genetic alterations. The progression from primary to metastatic lesions involved the acquisition of additional mutations, and/or shifts from subclonal to clonal mutations. Our findings suggest that mesonephric-like carcinomas are derived from a Müllerian substrate with differentiation along Wolffian/mesonephric lines.

Extrauterine Mesonephric-like Neoplasms: Expanding the Morphologic Spectrum

Mesonephric-like adenocarcinomas (MLA) are rare neoplasms arising in the uterine corpus and ovary which have been added to the recent 2020 World Health Organization Classification of Female Genital Tumors. They have similar morphology and immunophenotype and exhibit molecular aberrations similar to cervical mesonephric adenocarcinomas. It is debated as to whether they are of mesonephric or Mullerian origin. We describe the clinical, pathologic, immunohistochemical, and molecular features of 5 cases of extrauterine mesonephric-like proliferations (4 ovary, 1 extraovarian), all with novel and hitherto unreported features. These include an origin of MLA in extraovarian endometriosis, an association of ovarian MLA with high-grade serous carcinoma, mixed germ cell tumor and mature teratoma, and a borderline ovarian endometrioid tumor exhibiting mesonephric differentiation. Four of the cases exhibited a KRAS variant and 3 also a PIK3CA variant. In reporting these cases, we expand on the published tumor types associated with MLA and report for the first time a borderline tumor exhibiting mesonephric differentiation. We show the value of molecular testing in helping to confirm a mesonephric-like lesion and in determining the relationship between the different neoplastic components. We provide further evidence for a Mullerian origin, rather than a true mesonephric origin, in some of these cases. We also speculate that in the 2 cases associated with germ cell neoplasms, the MLA arose out of the germ cell tumor.

Mesonephric (Wolffian-derived) Adenocarcinoma of the Female Urethra

The current World Health Organization (WHO) classification of adenocarcinoma of the urinary tract including the urethra includes uncommon Müllerian-derived carcinomas such as clear cell and endometrioid adenocarcinomas. The concept of primary mesonephric (Wolffian-derived) adenocarcinoma (MA) in the urethra (and urinary tract in general) is currently regarded as controversial as the term "mesonephric" had been also inaccurately applied in the past to label Müllerian-derived carcinomas, particularly clear cell adenocarcinoma. Further, pathologically well-documented or bona fide urethral MAs have not yet to be reported. Herein, we describe 2 examples of MA in elderly females that primarily presented in the urethra and manifested clinically with obstructive lower urinary tract symptoms. Both tumors exhibited histology similar to those in MAs of the female genital tract including the distinctive tubular proliferations with luminal eosinophilic materials. The first case, in addition, showed a variety of patterns including ductal (glandular), solid, fused/sieve-like tubules, dilated tubules, and spindled cells. The second case also showed a transition to the more irregular and poorly formed tubular proliferation of cells with greater nuclear atypia and with a desmoplastic response. Both tumors showed positivity for PAX8, GATA3, and luminal CD10, and 1 tumor analyzed harbored KRAS and ARID1A mutations. One patient received neoadjuvant chemotherapy and underwent resection but had local tumor recurrence and metastasis to the lungs and lumbar spine 12 months after presentation. In conclusion, MA, similar to those occurring in the female genital tract and distinct from the recognized Müllerian-derived carcinomas, may present primarily as urethral tumors. MA in the urethra probably shares a common pathogenesis with vaginal MA as both may originate from the same caudal loci of mesonephric remnants along the closely apposed anterior vaginal and posterior urethral walls. MA should be considered in future classifications for urethral tumors and we recommend that the confusing term "mesonephroid adenocarcinoma" should no longer be used.

Mesonephric-Like Adenocarcinoma of the Endometrium: Diagnostic Advances to Spot This Wolf in Sheep's Clothing. A Review of the Literature

Mesonephric-like adenocarcinoma is a recently described rare neoplasm occurring in the uterine corpus and ovary. This under-recognized subtype of carcinoma can be very challenging to diagnose. In mesonephric adenocarcinoma a variety of growth patterns can be present within the same tumor, as a result of which they can be misinterpreted and diagnosed as low-grade endometrioid adenocarcinoma, clear cell carcinoma, or even serous carcinoma and carcinosarcoma. We report a case of mesonephric-like adenocarcinoma misdiagnosed as a low-grade endometrioid endometrial adenocarcinoma that had an early local recurrence and metastasized to the liver and the lungs. Histopathological, immunohistochemical and molecular analysis were performed and compared to published literature, providing a comprehensive overview of the current knowledge. Databases (Pubmed, Web of Science, Google Scholar) were searched with a combination of the following search terms: mesonephric-like, mesonephric, adenocarcinoma, carcinoma, uterine body, uterine corpus, endometrium. Mesonephric-like adenocarcinoma is a difficult-to-diagnose entity. Advanced diagnostics, including improved morphologic, immunohistochemical and molecular knowledge can help develop new therapeutic strategies against this specific subtype of endometrial cancer with an aggressive clinical behavior.

Cytohistopathologic correlation of ovarian mesonephric-like carcinoma and female adnexal tumor of probable Wolffian origin

Recently we encountered two cases with mesonephric features, mesonephric-like carcinoma (MLC) of the ovary, and female adnexal tumor of probable Wolffian origin (FATWO). They are thought to be related to mesonephric remnants (or Wolffian duct remnants). Herein we describe the cytohistolgical features, differential diagnoses, and potential pitfalls in diagnosis of these neoplasms. On cytological examination, the case of MLC showed tight 3-dimensional clusters of overlapping round cells, corresponding to solid growth pattern seen on histological examination. Tubular architecture and papillary formations composed of neoplastic cells of medium size with scant cytoplasm were readily identified. Intraluminal eosinophilic secretions were better seen on histological examination. Additionally, areas resembling features of papillary thyroid carcinoma were noted. Mitoses and apoptotic bodies were not identified on cytology but seen on histological sections. The neoplastic cells were positive for CK7, CD10, PAX-8, TTF-1, and GATA-3, and negative for ER, PR, and WT-1 immunostains. In contrast to MLC, cytological examination of FATWO showed smaller oval to spindle monotonous cells without mitotic figures. Some cells contained paranuclear vacuoles and were arranged individually or in loose cohesive clusters. Other cells were closely associated with pericellular hyalinized basement membrane-like material and they were arranged in cohesive clusters as well. On histological examination, similar to MLC, the FATWO had areas with thyroid-like features, such as, intraluminal eosinophilic secretions, paranuclear vacuoles, in the background of collagenous stroma. The neoplastic cells were positive for CK AE1/AE3, calretinin, WT-1, inhibin, and CD10, and negative for CK7, PAX-8, GATA-3, ER, PR, and C-kit immunostains.

Mesonephric-like adenocarcinoma of the ovary with co-existent endometriosis: A case report and review of the literature

Introduction

Mesonephric-like adenocarcinoma (MLA) is a rare malignant gynecologic neoplasm occurring in the uterine corpus and ovary. The morphological and immunohistochemical characteristics of MLA closely resemble that of cervical mesonephric adenocarcinomas, but whether they share a common histogenesis remains unclear. Two main theories for histogenesis of MLAs include the origination of these neoplasms from mesonephric remnants, as is the case for cervical mesonephric adenocarcinoma, versus the differentiation along a mesonephric pathway from Mullerian lesions.

Case

A 67-year-old presented after a right salpingo-oophorectomy for a complex ovarian mass revealed a mesonephric-like adenocarcinoma of the ovary and endometriosis. She underwent a total abdominal hysterectomy, pelvic lymphadenectomy, and infra-colic omentectomy, and diagnosed with Stage IA mesonephric-like adenocarcinoma of the ovary. At 18 months post-operatively, the patient developed flank and abdominal pain and was found to have multiple sites of recurrent disease. She was referred to medical oncology for chemotherapy as she was not a candidate for surgical cytoreduction.

Discussion

This case demonstrates the aggressive nature of ovarian MLA and the need for a multidisciplinary approach when determining the treatment. In addition, this case provides further evidence to support the theory that at least a subset of MLAs arises from a Mullerian lesion which then differentiates down a mesonephric pathway.

Endometriosis-related pathology: a discussion of selected uncommon benign, premalignant and malignant lesions

Endometriosis is an extremely common condition and, in most cases, establishing a histological diagnosis is straightforward, although a variety of benign alterations may result in problems with interpretation. In this review, I discuss selected uncommon variants of endometriosis or benign alterations that may result in diagnostic problems. The topics covered include the contentious issue of so-called atypical endometriosis, stromal endometriosis, polypoid endometriosis, and the association of endometriosis with florid mesothelial hyperplasia. The propensity of endometriosis to undergo neoplastic transformation (especially to endometrioid and clear cell carcinoma) is well known. Selected issues relating to the various neoplasms that can arise in endometriosis are discussed, with a particular concentration on unusual variants of endometrioid carcinoma that result in a disproportionately high number of issues in referral practice. The propensity of ovarian endometrioid carcinomas to show an unexpected ('aberrant') immunophenotype with positive staining with 'intestinal' markers and negative staining with Mullerian markers is also discussed. Uncommon tumour types that may arise in endometriosis, namely seromucinous neoplasms, mesonephric-like carcinomas, and somatically derived yolk sac tumours, are also covered.

Ovarian Combined Low-grade Serous and Mesonephric-like Adenocarcinoma: Further Evidence for A Mullerian Origin of Mesonephric-like Adenocarcinoma

Mesonephric-like adenocarcinomas are rare neoplasms occurring in the uterine corpus and ovary which bear a close morphologic resemblance to cervical mesonephric adenocarcinomas. They also have a similar immunophenotype and harbor similar molecular abnormalities to mesonephric adenocarcinomas and it is debated whether they are truly of mesonephric origin or represent Mullerian neoplasms closely mimicking mesonephric adenocarcinomas. We report an unusual case with bilateral ovarian serous borderline tumors and extraovarian low-grade serous carcinoma (invasive implants). In one ovary, there was a component of mesonephric-like adenocarcinoma. The immunophenotypes of the serous and the mesonephric-like components were distinct and as expected for the individual tumor types (serous component diffusely positive with WT1 and estrogen receptor and negative with GATA3, TTF1 and CD10; mesonephric-like component WT1 and estrogen receptor negative and GATA3, TTF1, and CD10 positive; both components diffusely positive with PAX8 and exhibiting "wild-type" p53 immunoreactivity). In all components (bilateral serous borderline tumors, low-grade serous carcinoma and mesonephric-like adenocarcinoma), an identical KRAS mutation was detected (NM_004985.4): c.35G>A, p.(G12D) proving a clonal association between the serous and mesonephric-like components and excluding a collision neoplasm. This represents the second reported case of a combined ovarian low-grade serous tumor and mesonephric-like adenocarcinoma; in the previously reported case, an identical NRAS mutation was present in both components. These 2 cases provide evidence that ovarian mesonephric-like adenocarcinomas have, at least in some cases, a Mullerian origin and differentiate along mesonephric lines. We present additional evidence for this by reviewing associated findings in published and unpublished ovarian mesonephric-like adenocarcinomas; 8 of 11 of these neoplasms contained other Mullerian lesions in the same ovary, mainly endometriosis and adenomas/adenofibromas.

Mesonephric adenocarcinoma of the uterine cervix with rare lung metastases: A case report and review of the literature

BACKGROUND

Mesonephric adenocarcinoma (MNA) of the female reproductive system is a rare tumor arising from remnants of the mesonephric duct, which is mainly located in the cervix. MNA often occurs in adult women. Due to the rarity of the disease and few reports, the specific clinical features have not been established.

CASE SUMMARY

We present a case of a cervical MNA in a 48-year-old woman with an incidental intra-operative diagnosis who received postoperative chemotherapy. Rare lung metastases were detected during follow-up. The existing literature is reviewed.

CONCLUSION

The clinical manifestations, pathological characteristics, diagnosis, treatment, and prognosis of MNA have been summarized through the review of the existing literature and the case in this paper. Due to the rarity of this disease, it is very important for the research of MNA in the future.

A Comprehensive Review of Biomarker Use in the Gynecologic Tract Including Differential Diagnoses and Diagnostic Pitfalls

Morphologic (ie, hematoxylin and eosin) evaluation of the Mullerian tract remains the gold standard for diagnostic evaluation; nevertheless, ancillary/biomarker studies are increasingly utilized in daily practice to assist in the subclassification of gynecologic lesions and tumors. The most frequently utilized "biomarker" technique is immunohistochemistry; however, in situ hybridization (chromogenic and fluorescence), chromosomal evaluation, and molecular analysis can also be utilized to aid in diagnosis. This review focuses on the use of immunohistochemistry in the Mullerian tract, and discusses common antibody panels, sensitivity and specificity of specific antibodies, and points out potential diagnostic pitfalls when using such antibodies.

Mesonephric-like Carcinoma of the Endometrium: A Subset of Endometrial Carcinoma With an Aggressive Behavior

Endometrial mesonephric-like carcinomas (MLCa) are uncommon with <50 reported cases thus far. Previous studies have characterized the histologic, immunohistochemical, and molecular features of MLCa; however, there is limited information with respect to outcome. This single-institution study of 23 uterine MLCas characterizes the behavior of such a neoplasm. Uterine MLCas (2004-present) had review of histologic features, immunohistochemical results, molecular profile, and clinical information (stage, treatment, follow-up). The behavior of MLCa was compared with low-grade endometrioid carcinomas (ECas) and uterine serous carcinomas (USCs) treated at our institution from 2004 to present. All MLCas had a mixture of previously described architectural and cytologic features most notably ductal and/or tubular architecture (21/23), nuclei resembling those of papillary thyroid carcinoma (18/23), and at least focal intraluminal eosinophilic secretions (20/23). Immunoperoxidase studies facilitated diagnosis in 22 cases: CD10, 10/10; calretinin, 5/15; estrogen receptor (≥10% nuclei), 6/21; progesterone receptor, 1/15; GATA-3, 15/16; TTF-1, 11/16. Fourteen of 17 tested cases had a KRAS mutation (7 as the only alteration; 7 with additional mutations including PIK [n=5]; PTEN [n=2], CTNNB1 [n=1]).One case had mutations in PTEN, PIK, and CTNNB1 without KRAS; 2 cases had no detectable somatic mutation. Overall, 48% of patients presented with International Federation of Gynecology and Obstetrics (FIGO) stage 3 or 4 disease with the following uterine risk factors: >50% myometrial invasion, 20/23; lymphovascular space invasion, 16/23; cervical stromal invasion, 7/23. Twenty patients had adjuvant therapy (7 radiation only; 13 chemotherapy±radiation), whereas 3 patients had either unknown or declined therapy. Follow-up was known for 21 patients: 17 patients had recurrences or never achieved remission with the lung being the most common recurrence site (n=9); 7 patients died of disease. The median progression-free survival was 18.2 months for MLCa compared with 183 months for ECa and 67.1 months for USC. The median overall survival for MLCa was 70.6 months compared with 139.1 months for USC (median survival for ECa not reached). Uterine MLCa is uncommon with most tumors recognized by architectural heterogeneity, vesicular, overlapping nuclei with grooves, and eosinophilic luminal secretions. The typical immunoprofile includes low to absent expression of hormone receptors but at least focal expression of GATA-3 and/or TTF-1. Most tested cases had a KRAS mutation although genetic mutations typically associated with ECa are not uncommon. Compared with more commonly encountered types of ECa, MLCa is more aggressive with a tendency towards earlier and distant recurrence.

Targeted Genomic Profiling of Female Adnexal Tumors of Probable Wolffian Origin (FATWO)

Female adnexal tumor of probable Wolffian origin (FATWO) is a rare gynecologic neoplasm of low-malignant potential presumed to be derived from mesonephric remnants in the upper female genital tract. Similarly, mesonephric remnants in the lower female genital tract are thought to be the origin for mesonephric carcinoma. Although the molecular alterations in mesonephric carcinoma have been recently reported, the pathogenesis of and molecular alterations in FATWO are not well understood. The aims of this study were to examine the molecular alterations in FATWO and to establish whether these neoplasms are molecularly similar to mesonephric carcinoma. Eight FATWOs underwent massively parallel sequencing to detect single nucleotide variations, copy number variations, and structural variants by surveying exonic DNA sequences of 300 cancer genes and 113 introns across 35 genes. Good quality DNA was isolated from 7 of 8 cases. Novel KMT2D variants (1 frameshift, 3 missense) were identified in 4 of 7 cases (57%), but were variants of uncertain biologic significance. STK11 mutations (both frameshift) were identified in 2 of 7 cases (29%); one of these was in a patient with a known history of Peutz-Jeghers syndrome. A mutation in the chromatin remodeling gene ARID1B was identified in 1 of 7 cases (14%). No cases harbored KRAS, NRAS, TP53, PIK3CA, PTEN, or DICER1 mutations. There were relatively low numbers of copy number variations, and no recurrent copy number variations were identified. One case demonstrated moderate copy gain of CCND1. No structural variants were identified. In summary, FATWO is characterized molecularly by the absence of KRAS/NRAS mutations (characteristic of mesonephric carcinoma), absence of DICER1 mutations (characteristic of Sertoli-Leydig cell tumor) and frequent KMT2D mutations of unknown biologic significance. FATWOs exhibit a limited number of molecular aberrations that are significantly different from those reported in tumors in the differential diagnosis, and our results question the relationship of mesonephric carcinoma with FATWO. Disease-defining molecular alterations for FATWO have yet to be discovered.

Mesonephric-like adenocarcinomas of the uterine corpus: report of a case series and review of the literature indicating poor prognosis for this subtype of endometrial adenocarcinoma

PURPOSE

Endometrial mesonephric-like adenocarcinoma (ML-AC) represents a recently recognized subtype of endometrial adenocarcinoma (AC) associated with a subtle immunophenotype with a characteristic KRAS-mutation. Detailed clinico-pathologic analyses and prognostic data on ML-AC are limited.

METHODS

We report a series of four cases with histopathological, immunohistochemical, and molecular analyses. These cases as well as the data of previously published cases were reviewed for clinico-pathologic variables and clinical follow-up information.

RESULTS

Forty cases of ML-AC were identified. ML-AC represents about 1% of all endometrial carcinomas. Similar to other types of endometrial AC, vaginal bleeding was the leading presenting symptom, and the mean age was 60.0 years (range 31-91). More than a half of the patients presented with locally advanced disease (≥ FIGO stage II) at time of diagnosis, developed a recurrence or died of the disease within a mean follow-up period of 24.7 months (range 3-144.5 months). The most common site of distant disease was pulmonary involvement. Microscopically, ML-ACs present with mixed morphology and show a co-expression of so-called mesonephric and Müllerian markers, suggesting a Müllerian origin of the tumors. Immunostaining for PD-L1 was negative in all tested cases, using different antibodies against PD-L1. Retained staining for mismatch repair proteins on immunohistochemistry and a POLE-mutation suggest a copy number low phenotype within the molecular classification of endometrial carcinomas. Almost all cases showed a KRAS-mutation at codon 12 (mostly G12V).

CONCLUSION

Uterine ML-AC represents a distinct subtype of invasive endometrial AC, associated with KRAS-mutations and characteristic immunohistochemical findings. Clinically, ML-AC may show an aggressive behavior with a high rate of recurrent disease and a substantial risk for distant metastatic disease, especially to the lungs.

A Combined Morphologic and Molecular Approach to Retrospectively Identify KRAS-Mutated Mesonephric-like Adenocarcinomas of the Endometrium

An unusual subset of endometrial carcinoma, the mesonephric-like adenocarcinomas, are morphologically and molecularly similar to mesonephric carcinoma, characterized by KRAS mutation and lack of microsatellite instability. They also have a unique immunohistochemical profile and are usually positive for GATA-3, CD10, TTF-1, and negative for ER and PR. This study implemented a combined morphologic and molecular approach to retrospectively identify mesonephric-like carcinomas of the endometrium. KRAS-mutated microsatellite stable (MSS) endometrial carcinomas were identified from a database of 570 endometrial carcinomas that had undergone massively parallel sequencing. MSS tumors with canonical KRAS mutations that lacked features diagnostic of endometrioid carcinoma (including squamous or mucinous differentiation), were re-reviewed for morphologic features of mesonephric-like adenocarcinomas. Ninty-eight of 570 endometrial carcinomas (17%) harbored canonical KRAS mutations. Of the KRAS-mutated cases, 80 (82%) were MSS and 18 (18%) had microsatellite instability. Of the KRAS-mutated MSS cases with morphology review, 39/61 (64%) had squamous and/or mucinous differentiation while 22 (36%) lacked these histotype-defining features. Eight of these 22 had PTEN mutations and lacked morphologic features of mesonephric-like adenocarcinoma, leaving 14 cases with a possible mesonephric-like adenocarcinoma-like molecular profile that underwent detailed morphologic re-review. Ten of 14 had morphology typical of serous (3), carcinosarcoma (4), or endometrioid (3) carcinoma. In 4 cases, there was striking morphologic, immunophenotypic, and molecular resemblance to mesonephric carcinoma, leading to re-classification as mesonephric-like adenocarcinoma. Two of the 4 cases presented at an advanced stage, and a third case later developed distant metastases. On the basis of this retrospective study, KRAS-mutated mesonephric-like adenocarcinoma represents ∼1% of all endometrial carcinomas. Future prospective recognition of this unusual variant of endometrial carcinoma may be important given its possible aggressive nature.

Clinicopathologic and Molecular Characteristics of Mesonephric Adenocarcinoma Arising From the Uterine Body

Mesonephric adenocarcinoma (MNAC) is a rare tumor of the female genital tract mainly occurring in the uterine cervix. To date, only a few cases of MNAC arising from of the uterine body (UB-MNAC) have been reported. The clinicopathologic and molecular characteristics of UB-MNAC remain unknown. In this study, we investigated the clinical, histopathologic, immunohistochemical, and genetic features of UB-MNAC. In total, 11 cases were included. Six patients developed metastatic disease, most commonly in lungs (5/6). Histopathologically, UB-MNAC was characterized by an admixture of tubular, glandular, papillary, retiform, glomeruloid, sex cord-like, and comedonecrosis-like architectural patterns. Three adverse pathologic characteristics, including advanced International Federation of Gynecology and Obstetrics stage, high mitotic activity, and presence of lymphovascular the invasion, were independent factors predicting the development of metastasis. All cases were positive for GATA-binding protein 3 and paired box 2 expression and showed wild-type p53, patchy p16, and preserved PTEN expression, as indicated by immunohistochemistry. Next-generation sequencing using 12 samples (11 primary tumors and 1 metastatic tumor) revealed 42 single nucleotide variations in 16 genes, mostly in KRAS (10/12) and ARID1A (9/12). Copy number variation was found in 16 genomic regions, and consisted of 57 gains and 10 losses, with 1q gain (11/12) being the most prevalent. In conclusion, UB-MNAC displays an aggressive biological behavior, with a tendency to metastasize to the lungs. Adverse pathologic characteristics reflect the aggressive nature of UB-MNAC. Distinct molecular features of UB-MNAC include frequent somatic mutations of KRAS and ARID1A and gain of 1q.

A Comparison of GATA3, TTF1, CD10, and Calretinin in Identifying Mesonephric and Mesonephric-like Carcinomas of the Gynecologic Tract

Mesonephric carcinomas of the gynecologic tract are neoplasms that are often under-recognized due to their varied morphologic appearances. Recently, GATA3 and TTF1 have been reported to be useful immunohistochemical markers for distinguishing mesonephric carcinomas from its morphologic mimics. Herein, we compared the performance of GATA3 and TTF1 to the traditional markers used for mesonephric carcinomas, CD10 and calretinin. We studied 694 cases: 8 mesonephric carcinomas (7 cervical [includes 3 mesonephric carcinosarcomas], 1 vaginal), 5 mesonephric-like carcinomas (4 uterine corpus, 1 ovarian), 585 endometrial adenocarcinomas, and 96 cervical adenocarcinomas. Mesonephric-like carcinomas were defined as tumors exhibiting the classic morphologic features of mesonephric carcinoma, but occurring outside of the cervix and without convincing mesonephric remnants. GATA3 had the highest sensitivity and specificity (91% and 94%) compared with TTF1 (45% and 99%), CD10 (73% and 83%), and calretinin (36% and 89%). GATA3, however, also stained a substantial number of uterine carcinosarcomas (23/113, 20%). TTF1 was positive in 5/5 (100%) mesonephric-like carcinomas and only 1/8 (13%) mesonephric carcinomas. In 4/6 (67%) TTF1 positive cases, GATA3 exhibited an inverse staining pattern with TTF1. In summary, GATA3 was the best overall marker for mesonephric and mesonephric-like carcinomas, but cannot be used to distinguish mesonephric carcinosarcomas from Müllerian carcinosarcomas. The inverse staining pattern between GATA3 and TTF1, suggests that TTF1 may be useful when GATA3 is negative in small biopsies where mesonephric or mesonephric-like carcinoma is suspected. The greater TTF1 positivity in mesonephric-like carcinomas suggests they may be biologically different from prototypical mesonephric carcinomas.

Mesonephric Adenocarcinoma of the Uterine Corpus: Report of 2 Cases and Review of the Literature

Mesonephric adenocarcinoma (MNA) is believed to arise from benign mesonephric remnants or hyperplasia located in the lateral walls of the uterine cervix. They are uncommon in other sites of the gynecologic tract, and exceptionally rare in the uterine corpus. So far, only 30 cases of uterine MNA have been reported in the literature, as a result, the etiology, clinical behavior, choice of treatment, and histogenesis of uterine MNA are still unclear. In this study, we report 2 cases of MNA of uterine corpus. One case involved the inner half of myometrium with endometrial involvement; the second case involved the outer half of myometrium without endometrial involvement. We also reviewed the clinical and pathologic presentations of this rare entity, and discussed the histogenesis of uterine corpus MNA based on recent molecular findings.

Cytologic features of upper gynecologic tract adenocarcinomas exhibiting mesonephric-like differentiation

BACKGROUND

Mesonephric adenocarcinomas are rare neoplasms which most commonly arise in the lateral cervix and vagina. Tumors with similar morphologic, immunophenotypic, and molecular characteristics recently have been described in the uterine corpus and ovary. Herein, the authors sought to characterize the cytomorphologic features of adenocarcinomas exhibiting mesonephric-like differentiation arising in the upper gynecologic tract.

METHODS

Institutional databases were queried retrospectively for tumors of the upper gynecologic tract described as a "tumor of Wolffian origin" or "with mesonephric features" between 2007 and 2017. All available cytologic material was reviewed. Cytomorphologic characteristics were evaluated by 3 pathologists.

RESULTS

The current study cohort consisted of 8 cases taken from 7 patients. Primary sites included the ovary (3 cases); endometrium (4 cases); and pelvis, not otherwise specified (1 case). All cases demonstrated tight 3-dimensional clusters of overlapping cells. Additional architectural features included tubular (5 of 8 cases; 63%) and papillary (3 of 8 cases; 38%) formations. Cells were small with scant (7 of 8 cases; 88%) to moderate (1 of 8 cases; 12%) cytoplasm. Three of the 8 cases (38%) demonstrated extracellular hyaline globules. Nuclei were uniform in size (6 of 8 cases; 75%) or showed mild anisonucleosis (2 of 8 cases; 25%). Nuclear grooves and indentations were observed in all cases. Mitoses (5 of 8 cases; 63%) and apoptotic bodies (4 of 8 cases; 50%), when present, were rare. No necrosis was noted.

CONCLUSIONS

Adenocarcinomas exhibiting mesonephric-like differentiation show a monotonous population of small cells with scant to moderate cytoplasm and abundant nuclear grooves arranged in tight, overlapping, 3-dimensional clusters. Occasionally, papillary or tubular architecture, as well as extracellular hyaline globules, may be seen. These features should prompt further testing (eg, immunohistochemistry) to confirm the diagnosis and to exclude potential mimics.

Diagnostic Algorithmic Proposal Based on Comprehensive Immunohistochemical Evaluation of 297 Invasive Endocervical Adenocarcinomas

The International Endocervical Adenocarcinoma Criteria and Classification was developed to separate endocervical adenocarcinomas (ECAs) into 2 main categories on the basis of morphology such as human papilloma virus-associated (HPVA) and non-human papilloma virus-associated adenocarcinomas. We aimed to improve the diagnostic accuracy of International Endocervical Adenocarcinoma Criteria and Classification by performing a comprehensive immunohistochemical evaluation and constructing objective immunohistochemical-based algorithms for the classification of these tumors. Tissue microarrays were constructed from 297 of 409 cases used to develop the original classification. Immunostains included p16, p53, estrogen receptor (ER), progesterone receptor, androgen receptor, Vimentin, CK7, CK20, HER2, HIK1083, MUC6, CA-IX, SATB2, HNF-1beta, napsin A, PAX8, CDX2, GATA3, p63, p40, and TTF-1. High-risk human papilloma virus (HR-HPV) was detected by in situ hybridization (ISH) using probes against E6 and E7 mRNA expressed in 18 different virus types. Vimentin, ER, and progesterone receptor were expressed in a significant minority of ECAs, mostly HPVAs, limiting their use in differential diagnosis of endometrioid carcinoma when unaccompanied by HPV-ISH or p16. HR-HPV ISH had superior sensitivity, specificity, and negative and positive predictive values compared with p16, as published previously. HNF-1beta did not have the anticipated discriminatory power for clear cell carcinoma, nor did MUC6 or CA-IX for gastric-type carcinoma. HNF-1beta and napsin A were variably expressed in clear cell carcinoma, with HNF-1beta demonstrating less specificity, as it was ubiquitously expressed in gastric-type carcinoma and in the majority of HPV-associated mucinous (predominantly intestinal-type and invasive ECA resembling stratified mucin-producing intraepithelial lesion [iSMILE]) and usual-type carcinomas. HIK1083 was expressed in nearly half of gastric-type carcinomas, but not in the vast majority of other subtypes. GATA3 was positive in 10% of usual-type adenocarcinomas and in single examples of other subtypes. Rare gastric-type and HPVA mucinous carcinomas displayed HER2 overexpression. Androgen receptor was positive in 6% of usual-type adenocarcinomas. Aberrant p53 expression was found in only 3.6% of usual-type HPVA carcinomas, but it was more prevalent in mucinous (intestinal type and iSMILE) HPVAs and non-human papilloma virus-associates (particularly in gastric-type carcinoma, >50% of cases). The following diagnostic classification algorithms were developed with the above data. Carcinomas without overt cytoplasmic mucin (endometrioid, usual-type endocervical, clear cell, and mesonephric carcinomas) can be subclassified using HR-HPV ISH, ER, and GATA3, whereas carcinomas with easily appreciated cytoplasmic mucin (endometrioid carcinoma with mucinous features, HPVA mucinous, and gastric-type carcinomas) can be subclassified with HR-HPV ISH and ER.

Mesonephric adenocarcinoma of the cervix: a case report with a three-year follow-up, lung metastases, and next-generation sequencing analysis

Background

Mesonephric adenocarcinoma (MNAC) is a rare tumor of the female genital tract, which originates from mesonephric duct remnants. Its diagnosis is pathologically challenging, because MNAC may exhibit a mixture of morphological patterns that complicates the differential diagnosis.

Case presentation

The patient in this case was a 48-year-old woman with a polypoid mass protruding into the endocervical canal. The patient underwent a total hysterectomy outside the institution. During biopsy, the mass showed a cerebroid aspect. Histological study revealed a tumor with a predominantly tubular and ductal growth pattern. The immunoprofile showed negative staining for calretinin, carcinoembryonic antigen (CEAm), estrogen receptors (ER), and progesterone receptors (PR), and positive staining for CD10, p16, and PAX2. The Ki-67 score was 46%. Using a next-generation sequencing assay, we documented genomic alterations in KRAS and CTNNB1, low tumor mutation burden (TMB), and an absence of microsatellite instability. In addition, gain of the long arm of chromosome 1 (1q) was also documented using chomogenic in situ hybridization (CISH). Three years later, the patient presented pulmonary nodules in the lingula and left basal lobe that were resected by thoracotomy. The histopathologic study of the pulmonary nodules confirmed the presence of metastases.

Conclusion

Carcinomas of mesonephric origin are among the rarest subtypes of cervical tumors. We report the first case of mesonephric adenocarcinoma of the cervix with lung metastases showing a CTNNB1 gene mutation.

Coexistence of endometrial mesonephric-like adenocarcinoma and endometrioid carcinoma suggests a Müllerian duct lineage: a case report

Background

Endometrial mesonephric-like adenocarcinomas exhibit classical histologic features of mesonephric carcinoma; however, it remains unclear whether these tumors represent mesonephric (Wolffian) carcinoma or endometrioid (Müllerian) carcinomas that closely mimic mesonephric carcinoma.

Case presentation

A 32-year-old Japanese primigravida presented with atypical vaginal bleeding. An endometrial biopsy suggested low-grade endometrioid carcinoma, and she was administered medroxyprogesterone acetate. Her tumor recurred 6 years later, and she underwent hysterectomy, salpingo-oophorectomy, and omentectomy, at which point she was diagnosed with mesonephric-like adenocarcinoma of the uterine endometrium. Retrospective pathological review of the initial biopsy confirmed coexisting low-grade endometrioid carcinoma and mesonephric-like adenocarcinoma of the uterine endometrium. On immunohistochemistry, the endometrioid carcinoma component was diffuse positive for estrogen and progesterone receptors but negative for thyroid transcription factor 1. However, the mesonephric-like adenocarcinoma component exhibited a mixture of estrogen receptor- and thyroid transcription factor 1-positive cells within the same glands.

Conclusions

We encountered a patient with coexisting endometrial mesonephric-like adenocarcinoma and low-grade endometrioid carcinoma, which was treated using medroxyprogesterone acetate therapy, resulting in recurrence of mesonephric-like adenocarcinoma alone. These clinicopathological findings support the prevailing notions that mesonephric-like adenocarcinoma is a Müllerian adenocarcinoma exhibiting mesonephric differentiation.

Carcinosarcoma of the uterine cervix: a rare pathological finding originating from mesonephric remnants

Carcinosarcoma of the uterine cervix is a very rare tumour that has been described in less than 70 cases in the literature. It is less common compared with carcinosarcoma of the uterine corpus and it can have two origins: the Müllerian ducts and the mesonephric duct remnants. The association of mesonephric carcinoma with a sarcomatous component was reported in only 11 cases, including the following. We describe a case of a 64-year-old woman, presenting with vaginal bleeding and a cervical lesion reported as a sarcoma of endometrial stroma in the first biopsy. After exclusion of distant disease, she was submitted to radical surgery and the final histopathological examination showed a carcinosarcoma of the cervix with mesonephric origin.

[Ectopic tissue of the female genital tract]

Ectopias of female genital tissues are a common event in routine pathology. Mostly they derive from paramesonephric tissues displaced during embryonal development or later. However, gonadal-, mesonephric-, or mesothelial-derived tissues may also appear in unusual localizations in and outside the female genital tract. They may be the source of benign and malignant tumors or tumor-like lesions. This review aims to provide an overview of possible tissue ectopias and to improve the developmental understanding of tumorous diseases of the female genital tract. Ectopias of primarily extragenital tissues in the female genital tract are also reviewed.

Mesonephric adenocarcinoma of the vagina masquerading as a suburethral cyst

Mesonephric adenocarcinoma (MA) of the vagina is an extremely rare tumour of the female genital tract. There are currently 22 reported cases in the published literature. Consequently, its pathophysiology and disease progression remain poorly understood.A 63-year-old woman presented with a history of a swelling in her vagina. Two-dimensional pelvic floor ultrasound and MRI demonstrated a multiloculated cyst with no malignant features. Initial workup provided a working diagnosis of a suburethral cyst. The diagnosis of MA was made on histology after excision of the cyst. Subsequent postoperative investigation showed no spread of the disease. The patient completed a course of prophylactic brachytherapy to prevent the possibility of any recurrence of disease. Due to its rarity, it remains difficult to diagnose MA of the vagina even on histological analysis. We would therefore recommend a low threshold to excise or perform tissue biopsy of unspecified vaginal masses.

Mixed Mesonephric Adenocarcinoma and High-grade Neuroendocrine Carcinoma of the Uterine Cervix: Case Description of a Previously Unreported Entity With Insights Into Its Molecular Pathogenesis

Human papillomavirus (HPV)-negative cervical carcinomas are uncommon and typically encompass unusual histologic subtypes. Mesonephric adenocarcinoma is one such subtype. Mesonephric tumors in the female genital tract are thought to arise from Wolffian remnants, and are extremely rare tumors with widely variable morphology. Sarcomatoid dedifferentiation has been previously described in a few cases, but other forms of dedifferentiation have not been reported. Neuroendocrine carcinoma of the cervix (e.g. small cell carcinoma) is associated with HPV infection, typically HPV 18. These tumors often arise in association with a conventional epithelial component such as squamous cell carcinoma or usual-type endocervical adenocarcinoma. We describe a case of mesonephric adenocarcinoma of the uterine cervix associated with an HPV-negative high-grade neuroendocrine carcinoma at the morphologic and immunophenotypic level, for which we performed targeted massively parallel sequencing analysis of the 2 elements. Both components shared identical mutations in U2AF1 p.R156H (c.467G>A) and GATA3 p.M422fs (c.1263dupG), as well as MYCN amplification. In addition, the neuroendocrine carcinoma harbored TP53 and MST1R mutations not present in the mesonephric carcinoma. Our data suggest a clonal origin of the 2 components of this rare entity, rather than a collision tumor.

Therapy Modalities, Prognostic Factors, and Outcome of the Primary Cervical Carcinosarcoma: Meta-analysis of Extremely Rare Tumor of Cervix

Objective

The aim of this study was to evaluate the prognostic factors, treatment options, and survival outcomes of primary carcinosarcomas of the uterine cervix.

Methods

An electronic search of the literature was conducted from 1951 to February 2017 to identify articles on primary cervical carcinosarcoma. After comprehensive evaluation of case series and case reports, 81 cases were included in the study.

Results

The most common clinical FIGO (International Federation of Gynecology and Obstetrics) stage was IB at 53% of cases. Median follow-up time was 15 months (range, 1.75–156 months). Two-year disease-free survival (DFS) and overall survival (OS) of the entire cohort were 49% and 60%, respectively. Both 2-year DFS and OS were significantly higher in patients with stage I than in those with stage II disease or greater (73% vs 22%, P = 0.000 and 82% vs 33%, P = 0.000, respectively). Two-year OS was 17% for patients who received primary radiotherapy, whereas it was 68% for those who underwent only surgery (P = 0.003). Surgery followed by adjuvant radiotherapy with or without chemotherapy was significantly associated with improved DFS and OS compared with primary radiotherapy. Two-year DFS was 63% in patients who underwent primary surgery, whereas it was 100% in patients treated with primary surgery followed by adjuvant radiotherapy with chemotherapy (P = 0.030). Stage alone was an independent prognostic factor for risk of both recurrence and death (hazard ratios, 9.8 [P = 0.004] and 14 [P = 0.018], respectively).

Conclusions

In due course of presentation, the tumor stage has a great importance because it is the only independent factor for prognosis. Surgery followed by adjuvant radiotherapy with or without chemotherapy seems to be related with better OS and DFS.

Mesonephric adenocarcinoma of the uterine corpus with intracystic growth completely confined to the myometrium: a case report and literature review

BACKGROUND

Mesonephric adenocarcinoma (MA) is a rare tumor believed to arise from mesonephric remnants occurring mostly in the uterine cervix and, to a lesser extent, the corpus. Since the first case report of MA in the corpus in 1995, only 16 cases have been reported in the English literature. A recent report suggested that MA originates in Müllerian tissue and exhibits the mesonephric differentiation phenotype.

CASE PRESENTATION

An asymptomatic 61-year-old woman was referred to our hospital because of elevated levels of tumor markers. Imaging revealed an intramural lesion of the uterine corpus exhibiting fluorodeoxyglucose uptake. A total hysterectomy and bilateral salpingo-oophorectomy were performed. The tumor was completely confined to the corpus wall and was composed of an intracystic bulky component and an invasive component in the myometrial layer. The tumor exhibited a variety of growth patterns, including a characteristic tubular pattern with dense eosinophilic secretion reminiscent of the thyroid, as well as a variety of morphologies, such as acinar, papillary, and ductal structures. The structures were immunoreactive for CK7, vimentin, CD10, calretinin, PAX8, and GATA3 and almost completely negative for ER/PgR. CA125 and CA19-9 antigen expression was also detected.

CONCLUSION

A case of MA with a unique growth pattern of an intracystic mass within the corpus wall is presented. The histogenesis and differential diagnoses are discussed. The histogenesis of MA is not yet clear. We hypothesize two different pathways involved: 1) direct development from the mesonephric remnants and/or 2) mesonephric transformation of Müllerian adenocarcinoma.

Mesonephric (Wolffian) Pseudoendometrioid Carcinoma of the Broad Ligament, Arising From a Papillary Cystadenoma

This article describes the case of a 70-year-old woman with an adnexal cystadenocarcinoma located in the right broad ligament and displaying a striking resemblance to a well-differentiated endometrioid adenocarcinoma. The uniqueness of this pseudoendometrioid carcinoma lies in the fact that its mesonephric nature is revealed by the origin from a papillary cystadenoma of the broad ligament, where remnants of the mesonephric duct are seated, and the immunohistochemical profile, particularly a uniform negativity for estrogen and progesterone receptors, apical-luminal positivity for CD10, and strong nuclear positivity for GATA3.

Mesonephric adenocarcinoma of the vagina : Diagnosis and multimodal treatment of a rare tumor and analysis of worldwide experience

Background

Mesonephric adenocarcinoma of the vagina is an extremely rare tumor of the female genital tract, with only a few cases reported so far worldwide. Consequently, there is no established standard treatment and limited knowledge about the prognosis and biologic behavior of vaginal mesonephric adenocarcinoma.

Methods

This report documents a new case of vaginal mesonephric adenocarcinoma diagnosed in a 54-year-old woman, and analyzes this in the context of all previously published cases.

Results

MRI demonstrated that the 2.5 × 1.8 cm tumor of the vaginal wall was invading urethra and bladder. Following surgical excision, histologic analysis determined mesonephric adenocarcinoma of the vagina, stage pT2 R1. In order to avoid the mutilating extended surgery which would be required to reach R0 and considerable impairment of quality of life, adjuvant radiochemotherapy was administered with external radiation and brachytherapy, including 5 cycles of cisplatin (40 mg/m²) for radiosensitization. After 4 years of continuous oncologic follow-up, the patient is alive and clinically free of disease.

Conclusion

In this case it was shown that adjuvant radiochemotherapy with radiation and brachytherapy was effective to manage the surgical R1 situation and maintain the patient’s life quality. More published cases reports are needed to gradually substantiate optimal treatment strategies.

Mesonephric adenocarcinoma of the cervix: Case report and literature review

A mesonephric adenocarcinoma of the cervix is a very rare tumor deriving from remnants of the mesonephric duct. Differential diagnosis from other cervical carcinomas is difficult and little is known regarding its biological behavior, prognosis, and the optimal management strategy. We present a case of a mesonephric adenocarcinoma of the cervix with a comprehensive review of the existing literature. In this case a 66-year-old woman presented with postmenopausal vaginal bleeding. She was diagnosed with a FIGO stage IIB mesonephric adenocarcinoma of the cervix and treated with neoadjuvant chemoradiotherapy and a Wertheim hysterectomy. The recovery from surgery was uneventful and the patient remains with no evidence of disease with 2 years of follow-up.

•

A mesonephric adenocarcinoma is a rare tumor deriving from remnants of the Wolffian duct.

•

Challenging diagnosis since this tumor can mimic more common adenocarcinomas.

•

Immunohistochemistry can be helpful in questionable cases.

•

Rational to base treatment on current guidelines for adenocarcinoma until more data.

•

It seems mesonephric carcinomas carry a worse prognosis.

Differential Expression Patterns of GATA3 in Uterine Mesonephric and Nonmesonephric Lesions

GATA binding protein 3 (GATA3) is a recently described immunohistochemical marker that has proven useful in the characterization of breast and urothelial carcinomas. However, the expression pattern of GATA3 in mesonephric proliferations is largely unknown. The aim of this study was to examine the immunohistochemical expression of GATA3 in cervicovaginal mesonephric lesions and compare it to its expression in endocervical and endometrial adenocarcinomas and cervicovaginal endometriosis. A cohort of 107 cases, including 33 cases of mesonephric lesions and 74 cases of nonmesonephric lesions, was selected for the study. Of 33 mesonephric lesions, 31 (94%) cases (16 remnants, 12 hyperplasias, and 3 adenocarcinomas) were strongly and diffusely positive in tumor cell nuclei for GATA3. The remaining 2 mesonephric carcinosarcomas showed focal nuclear staining and rare nuclear positivity, respectively. Of 36 endocervical adenocarcinomas, 33 (92%) were negative for GATA3 and the remaining revealed focal weak nuclear staining. Of 34 endometrial adenocarcinomas, 32 (94%) were negative, whereas 2 showed rare nuclear positivity. All 4 cases of endometriosis were negative. The benign endocervical epithelium and the benign endometrium in most cases lacked GATA3 expression, whereas the benign squamous epithelium in the majority exhibited nuclear basal and parabasal staining pattern. Our study demonstrates that GATA3 protein is expressed in most mesonephric lesions, regardless of them being benign or malignant. In contrast, GATA3 is absent in the majority of endometrial and endocervical adenocarcinomas. These results support that GATA3 immunostain can be a useful tool in differentiating mesonephric lesions from endocervical and endometrial adenocarcinomas.