Endodermal sinus tumor of the clitoris

A Subset of SMARCB1 (INI-1)-deficient vulvar neoplasms express germ cell markers

AIMS

SMARCB1 (INI-1)-deficient vulvar neoplasms comprise a group of rare tumours that include epithelioid sarcoma (ES), myoepithelial carcinoma (MEC), the recently described myoepithelioma-like tumour of the vulvar region (MELTVR), and sarcomas that are difficult to classify. It has been suggested that so-called vulvar yolk sac tumours (YST) may represent morphologic variants of SMARCB1-deficient tumours; thus, we investigated the immunoreactivity of germ cell markers in SMARCB1-deficient vulvar neoplasms.

METHODS AND RESULTS

Ten SMARCB1-deficient vulvar neoplasms were stained with germ cell tumour markers (SALL4, glypican-3, OCT3/4, and AFP) and re-reviewed for morphologic features. The tumours occurred in adult females (median age 41 years) and included ES (n = 7), MELTVR (n = 2), and MEC (n = 1). All cases showed loss of SMARCB1 expression. Four cases (40%) were focally positive for SALL4 in areas with morphology of typical-appearing ES. One of these cases also showed focal staining for OCT3/4. One ES showed a transition from typical-appearing ES to YST-like morphology, with diffuse expression of SALL4 and glypican-3, and focal expression of AFP, in these latter areas. All other tested cases were negative for AFP.

CONCLUSION

Our study reveals that SALL4, glypican-3, and OCT3/4 are positive in a subset of SMARCB1-deficient vulvar neoplasms, which may pose a diagnostic challenge and result in consideration of a germ cell tumour. We also highlight a case with transition from ES to YST-like morphology, lending further support that YSTs of the vulva are somatically derived SMARCB1-deficient neoplasms and do not represent true germ-cell neoplasia.

Vulvar Yolk Sac Tumors Are Somatically Derived SMARCB1 (INI-1)-Deficient Neoplasms

So-called primary yolk sac tumors of the vulva are very rare and often have an aggressive disease course. Their molecular features have not been previously characterized. There is also a well-documented group of SMARCB1 (INI-1)-deficient vulvar neoplasms, which includes proximal-type epithelioid sarcoma and myoepithelial carcinoma. Until now, "vulvar yolk sac tumors" and SMARCB1-deficient neoplasms were considered unrelated diseases. After reviewing an index case of a vulvar yolk sac tumor with loss of SMARCB1 by immunohistochemistry, we retrospectively identified 2 additional cases diagnosed as vulvar yolk sac tumors. Patient ages were 34, 32, and 25 years old, and 2 tumors were associated with a pregnancy. All 3 cases showed morphology typical of a yolk sac tumor, and by immunohistochemistry all were positive for SALL4, glypican-3, keratins, and lacked CD34 positivity. All tumors also demonstrated loss of SMARCB1 in tumor cells. Targeted molecular profiling was performed in 2 cases and identified 2 copy deletion of SMARCB1, without genomic alterations typically seen in gonadal yolk sac tumors. In the third case, isochromosome 12p was not identified by fluorescence in situ hybridization. All 3 patients had either local recurrences or distant metastases, and 2 died of disease. One patient had progressive disease while receiving the enhancer of zeste homolog 2 inhibitor tazemetostat. Overall, these findings suggest that vulvar tumors with pure yolk sac-like morphology may represent morphologic variants of SMARCB1-deficient tumors and not veritable germ cell neoplasia. This potential reclassification may have both prognostic and treatment implications and warrants study of additional extragonadal yolk sac tumors.

Pediatric vulvar malignancies: rare but important to know

Malignancies of the vulva in the pediatric population are exceptionally rare, which makes it difficult to gain any insight into their clinicopathologic profile. In this review, we summarize all published cases of a vulva malignancy in pediatric patients (≤21 years) reported in the English language literature for the 50-year period between 1970 and 2020. We estimate that less than 100 malignancies have been reported in total, approximately 50% of which were rhabdomyosarcomas. Invasive squamous cell carcinomas, yolk sac tumors, Ewing sarcoma/primitive neuroectodermal tumors (ES/PNET) and melanomas each represented approximately 10% of reported cases. For rhabdomyosarcoma, the alveolar and embryonal subtypes were reported with equal frequency, with both representing 70% of cases combined. The average patient age was 9.8 years. 48% and 35% were Intergroup Rhabdomyosarcoma Study clinical groupings I and III respectively. Managements were generally multimodal, and overall outcomes for the group were favorable. For invasive squamous cell carcinoma, the patients were all in their teenage years, with an average age at diagnosis of 15.2 years. A small subset of cases were associated with human papillomavirus and immunosuppression, and it is possible that immunosuppression has a role in vulvar squamous carcinogenesis in this population. One case was associated with lichen sclerosus. The patients with yolk sac tumors ranged in age from less than 1 year to 20 years (mean 12) and 67% of cases were stage I at presentation. An insufficient number of cases have been reported to define their prognosis, although some cases were notably aggressive. The few reported cases of melanoma are distinctive only because they were all associated with lichen sclerosus, suggestive of some role for the latter in their pathogenesis. The average age of patients reported with ES/PNET was 15 years (range 3.3 to 20). At least half of the reported cases were advanced stage at presentation, and patient outcomes were notably poor: 62.5% were dead of disease at follow-up. Pediatric vulvar malignancies are rare and are mostly comprised of 5 entities. Their accurate pathologic classification is necessary to facilitate optimal management.

Yolk Sac Tumor in Extragonadal Pelvic Sites: Still a Diagnostic Challenge

We present the clinicopathologic features of 15 cases of extragonadal yolk sac tumor (EGYST) detected in female patients and reviewed at our institution from 1988 to 2016. We recorded: patient age, clinical presentation, tumor location, FIGO stage (where applicable), histologic patterns including presence/absence of Schiller-Duval bodies, other germ cell or somatic components, immunoperoxidase results, treatment, and outcome. Patients' ages ranged from 17 to 87 (median, 62) years and presentation included: abnormal uterine bleeding, 12; hematuria, 1; labial mass, 1; abdominal pain, 1. Primary sites were as follows: uterus (11), vagina (1), vulva (1), bladder (1), and peritoneum (1). Seven patients presented at FIGO stage III or IV. The following histologic patterns were observed: microcystic/reticular (7), glandular (8), solid (8), papillary (5), and hepatoid (1). An admixture of histologic patterns was present in 10 cases. Schiller-Duval bodies were seen in only 3 (23%) cases. Eight cases (46%), all uterine primaries, had associated somatic components, and 2 (15%) had a second germ cell component. In 13/14 (93%) cases, the yolk sac tumor component was either missed or misclassified as adenocarcinoma. Immunoperoxidase studies facilitated the diagnosis in all cases as follows: SALL4, 12/12; CDX2, 10/12; α fetoprotein, 7/14; glypican-3, 9/10; cytokeratin 20, 5/9 (rare cells); cytokeratin 7, 3/12 (nondiffuse); PAX8, 2/9 (variable expression). All patients received chemotherapy and all except 1 underwent surgical resection. Follow-up from 5 to 86 months was available for 13 patients: 5 died of disease, 6 are alive with disease, and 2 have no evidence of disease. EGYST arising in the female pelvis of peri/postmenopausal patients may be associated with a somatic component and represent either somatically derived YST or YST differentiation within a somatic carcinoma. EGYST in younger patients is likely a true germ cell neoplasm, and may respond to germ cell appropriate chemotherapy. The benefit of germ cell appropriate chemotherapy in somatically derived EGYST is less clear. Awareness that the presence of glandular or microcystic patterns may lead to under-recognition or misdiagnosis of EGYST in combination with immunomarkers for germ cell and yolk sac differentiation will facilitate the diagnosis.

Unusual Presentations of Gynecologic Tumors: Extragonadal Yolk Sac Tumor of the Vulva

Extragonadal germ cell tumors are uncommon, and although they morphologically resemble their gonadal counterparts, unexpected gonadal presentation increases the potential for erroneous diagnoses. Yolk sac tumor is a malignant germ cell tumor characterized by an extraembryonic yolk sac line of differentiation, and relative to other germ cell tumors, is characterized by varied and diverse histologic patterns. When occurring outside of typical age parameters or in extragonadal locations, the histologic variability of yolk sac tumor and its tendency to mimic somatic tumors pose diagnostic challenges. Because extragonadal yolk sac tumor of the vulva is very rare, with only isolated case reports and small series in the literature, it is often not considered in the differential diagnosis. As both prognosis and management of yolk sac tumor differ significantly from those of somatic tumors, accurate diagnosis is essential. This review discusses histologic features of extragonadal yolk sac tumor, addresses somatic tumors arising in the vulva for which yolk sac tumor may be confused, and provides guidance with respect to the use of immunohistochemistry in the diagnosis of yolk sac tumor.

Literature Review of Periclitoral Cysts in the Prepubertal Population

STUDY OBJECTIVE

Clitoral cysts in the pediatric population are rare conditions that require careful evaluation. In this review of the literature we discuss the evaluation of clitoral abnormalities in the pediatric population, the development of clitoral cysts, and how to differentiate benign from malignant tumors. In addition, a summary of relevant cases of clitoral tumors in the literature are discussed.

DESIGN

Literature review.

DATA SOURCE

A MedLine and advanced PubMed search was conducted of all English language articles published using the search terms "clitoris" and "cyst" until February 2015. Reference tracing was completed for all articles for completeness.

MAIN OUTCOME

Literature review of clitoral cysts in the prepubertal population.

RESULTS

In total, we found 15 cases of benign, spontaneously forming clitoral cysts reported. Eleven of those cases document symptom onset before puberty. Reports of other benign clitoral lesions in the pediatric population include 1 angiokeratoma, 1 hemangiopericytoma, 1 granular cell tumor, 6 hemangiomas, and approximately 30 neurofibromas. Clitoral malignancies in the pediatric population are even more rare with only 3 cases of clitoral schwannomas, 2 rhabdomyosarcomas, 1 lymphoma, and 1 endodermal sinus tumor documented in the literature.

CONCLUSION

Clitoral cysts must be considered as a possible cause of clitoral enlargement in the prepubertal population. Clitoral tumors are distinguished clinically from hormonal abnormalities and intersex disorders by their hormonal profile, and the presence of an underlying mass. Ultrasound and magnetic resonance imaging might be useful imaging modalities to further characterize the clitoral enlargement. When confirmed as the most likely diagnosis, surgical resection is the mainstay of treatment for clitoral cysts.

Vulvar yolk sac tumor diagnosed during pregnancy, with recurrence during subsequent second pregnancy

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Vulvar yolk sac tumor (YST) is an exceptionally rare and aggressive extra-gonadal germ cell tumor, previously only described in 15 cases in the literature.

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We present a unique case of vulvar YST diagnosed during pregnancy, treated with systemic chemotherapy, who subsequently recurred during a second pregnancy.

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Despite salvage chemotherapy and autologous stem cell transplantation at recurrence, our patient succumbed to her disease, 31 months post diagnosis.

Lesions of the clitoris: a review

The clitoris may become involved by vulvar lesions. There are also lesions arising from the clitoris. A familiarity with these lesions is necessary for the high index of suspicion needed for their diagnosis.

Yolk sac tumor of the vulva: a case report with recurrence after long-term follow-up

A yolk sac tumor (YST) of the vulva is extremely rare and highly malignant with recurrence frequently occurring within a year. This report presents the 13th known case of vulvar YST, with recurrence occurring after the longest known follow-up period so far reported in the literature.

Yolk sac tumor of the vulva: a case report with long-term disease-free survival

BACKGROUND

Yolk sac tumor (YST) of the vulva is extremely rare. Seven cases of vulvar YST have been reported to the literature. Due to the rarity of tumors, the appropriate choice of treatment may remain unclear.

CASE

A 30-year-old woman presented with a 3.5-cm right labial mass. Excisional biopsy showed YST with predominant solid pattern. Three weeks after excision, right inguinal lymph node biopsy revealed metastatic tumor. The serum alpha-fetoprotein (AFP) was not elevated. Cisplatin-based chemotherapy was administered, followed by pelvic and groin irradiation. The patient was free of disease 90 months after the diagnosis.

CONCLUSION

Local excision of tumor with adjuvant cisplatin-based chemotherapy can be justified for vulvar YST. Inguinal lymphadenectomy is recommended because metastasis may occur early. Adjuvant radiation therapy may help to control the disease. Tumor size of 5 cm or less may be a favorable prognostic factor. Serum AFP level may not be a sensitive marker for follow-up of vulvar YST.

Endodermal sinus tumor of the vulva: successfully treated with high-dose chemotherapy

Endodermal sinus tumors (EST) of the lower female genital tract are uncommon malignancies. Most of these tumors are found in the vagina or in the cervix. Only seven cases of EST involving the vulva are reported. We report an eighth case of vulvar EST. The patient recurred and was successfully treated with high-dose chemotherapy and peripheral blood cell transplantation. Because of their location, an early diagnosis of vulvar EST should be possible. Resection of the lesion by using a modified radical vulvectomy followed by cisplatin-based chemotherapy seems the best treatment for these tumors today. Our patient was initially treated with the help of local surgery and adjuvant chemotherapy consisting of three courses of etoposide and cisplatin. Sixteen months after the first diagnosis, pleural and lung metastases were diagnosed. Second-line chemotherapy followed by high-dose chemotherapy with autologous peripheral blood stem cell support was administered after resection of the lung metastases and biopsy of the pleural metastases. There is no evidence of disease 40 months after the diagnosis of the lung and pleural metastases, and 56 months after the primary diagnosis.

The vulvar mass in the prepubertal child

The differential diagnosis of the vulvar mass in the prepubertal patient is extensive and reported cases of a vulvar hamartoma in the literature are limited. The case presented in this work and review of the literature demonstrate that when considering the differential diagnosis of vulvar masses in the prepubertal female, hamartoma should be included. This review outlines the differential diagnosis of the vulvar mass and gives a comprehensive review of benign masses arising from embryonic remnants, those of mesenchymal origin as well as sarcoma botryoides-embryonal rhabdomyosarcoma and the embryonal sinus tumor.

Primary endodermal sinus tumor of the vulva: a case report and review of the literature

BACKGROUND

Extragonadal endodermal sinus tumors arising in the external genitalia represent an exceedingly rare malignancy in women. Six cases of endodermal sinus tumors of the vulva have been reported to date, with three cases failing to respond to conservative surgery and vincristine-based chemotherapy. We report a seventh case of vulvar endodermal sinus tumor that was treated with radical surgery and platinum-based chemotherapy.

CASE

RT is an 18-year-old female who presented with a vulvar mass that was diagnosed as endodermal sinus tumor at the time of biopsy. She was subsequently treated with modified radical vulvectomy and ipsilateral groin lymphadenectomy, followed by bleomycin, etoposide, and cisplatin chemotherapeutic regimen. She has since remained free of disease for 18 months as evidenced by serum alpha-fetoprotein and physical exam at 18 months.

CONCLUSIONS

Vulvar endodermal sinus tumors represent a very small number of germ cell tumors in women. Based on the previous accounts, this disease appears to be more fatal than endodermal sinus tumor arising at other sites. These tumors also have a predilection for local metastasis. Due to the previous accounts, we chose to treat this patient with radical surgery and platinum-based chemotherapy. This treatment regimen has resulted in a disease-free state for 18 months.

Rhabdomyosarcoma of the clitoris

Genitourinary rhabdomyosarcoma in females usually originates in the vagina or uterus, but rarely the vulva. The authors present a case of rhabdomyosarcoma originating in the clitoris. A 4-year-old with an alveolar rhabdomyosarcoma of the clitoris was treated with radical clitorectomy, radiation, and chemotherapy. Follow-up at 3 years showed no active disease.

Endodermal sinus (yolk sac) tumor of the parotid gland: a case report

Malignant salivary gland neoplasms in children are rare, most common being mucoepidermoid carcinoma, adenoid cystic carcinoma, acinic cell carcinoma and adenocarcinoma. Most germ-cell neoplasms of head and neck in children are teratomas. The authors report a case of endodermal sinus tumor (EST) of the parotid gland in a 2-year-old girl, which recurred after chemotherapy. The role of alpha-fetoprotein (AFP) serum level as a helpful marker in differential diagnosis and in evaluating tumor progression is underlined.

Primary endodermal sinus tumor of the penis: a case report

We report a case of primary extragonadal germ cell tumor of the penis in a 2-year-old child with elevated serum alpha-fetoprotein. The patient responded well to a combination of bleomycin, etoposide and cisplatin, achieving a complete response within 3 cycles. He was alive and disease-free 8 months after diagnosis. To our knowledge this is the first case of an endodermal sinus tumor of the penis reported in the literature. The possible histogenesis of this tumor at such a rare site is discussed.

Extraovarian pelvic yolk sac tumors

The clinical and pathologic features of four extraovarian pelvic yolk sac tumors (YST) are described. The women, 17 to 39 years of age, were found to have a pelvic mass on physical examination, or in one case, at cesarean section. The tumors were bulky and arose within, or in close proximity to, the uterus. One tumor involved the endometrial cavity and myometrium extensively, another was attached to the anterior uterine serosa, another was in the cul-de-sac, and one lay between the lower uterine segment and urinary bladder. The ovaries were grossly unremarkable in all cases. Peritoneal metastases were present at the time of operation in two patients and were documented on histologic examination in a third. The serum alpha fetoprotein (AFP) level was elevated postoperatively in the three patients in whom it was determined. Three of the YST were pure and had a typical histologic appearance, whereas the fourth had an endometrioid-like glandular pattern and was associated with a teratoma. Immunohistochemical stains performed in three cases all showed AFP and alpha-1-antitrypsin (AAT). All patients received postoperative combination chemotherapy. Two of them died of tumor 14 and 24 months, respectively, postoperatively and two were disease-free 6 and 8.5 years, respectively, postoperatively.

Endodermal sinus (yolk sac) tumour of the liver. A case report and review of the literature

A primary endodermal sinus tumour of the liver which developed in a 27-year-old woman is reported. The dimensions of the tumour were 11 x 11 x 9.5 cm. Most parts were friable, haemorrhagic, and necrotic. No metastasis was found, but one part of the tumour was invading the diaphragm directly. Histologically, the tumour had mainly a reticular pattern, and partly a solid pattern, and was characterized by the presence of Schiller-Duval bodies and intra- and extracellular hyaline globules. A small part of the tumour showed a polyvesicular vitelline pattern and glandular structures with enteric differentiation. Serum alpha-fetoprotein was very high (28,500 ng/ml), but carcinoembryonic antigen was within the normal range. Immunohistochemically, most of the tumour cells contained alpha-fetoprotein and alpha-1-antitrypsin. Carcinoembryonic antigen and glutathione S-transferase, which was recently proved to be a useful marker for colonic carcinoma, were detected only in the glandular part Four previously reported cases of primary endodermal sinus tumour of the liver are reviewed.

Endodermal sinus tumor of the vagina: a report of nine cases and review of the literature

Nine cases of endodermal sinus tumor of the vagina from children 6 months to 2 years of age are reported. The two patients treated before the advent of modern chemotherapy died 6 to 13 months postoperatively despite attempted complete surgical resection of the tumor in one of the cases. One patient who was treated initially by hysterectomy and vaginectomy had lung metastases 6 months postoperatively and died despite chemotherapy. Six patients who were treated by a surgical procedure and received vincristine, actinomycin D, and cyclophosphamide, with radiation therapy in two cases, were alive and free of disease from 2 to 9 years postoperatively.