Vaginal Solitary Fibrous Tumor

Cellular angiofibroma of the vagina: A case report and literature review

BACKGROUND

Cellular angiofibroma (CAF), a rare benign mesenchymal tumor, is histologically characterized by abundant thick-walled vessels with a spindle cell component. As one of the female reproductive system tumors, its clinical and pathological features are not well characterized.

METHODS

A 47-year-old woman presented for the removal of intrauterine device on October 28, 2021, as she had achieved menopause one year back. The patient had no discomfort or awareness of any mass in her vagina. She has history of breast cancer and papillary thyroid cancer. Till date, no progression of thyroid cancer or breast cancer has been observed. Her menstrual cycle was regular, and she had one child delivered vaginally.

RESULTS

Pelvic examination revealed a mass sized 2.5 × 2.0 cm located near the fornix in the upper segment of the left vaginal wall. Thin prep cytologic test (TCT) revealed negative intraepithelial lesion or malignancy (NILM). HPV test was negative and leucorrhea routine inspection cleanliness II degree. No cervical mass was detected by ultrasound examination. The patients underwent the operation for intrauterine device removal plus vaginal tumor resection on November 1, 2021. Postoperative antibiotics (intravenous cefuroxime sodium 0.75 g bid for 1 day) were administered to prevent infection. The patient showed no signs of recurrence at one-month follow-up.

CONCLUSION

In summary, CAF is a rare benign soft tissue tumor. Surgery is the only treatment method, and the definitive diagnosis of CAF is based on histopathological examination of surgical specimen. Long-term follow-up is needed for surveillance of recurrence.

Solitary Fibrous Tumors of the Female Genital Tract: A Study of 27 Cases Emphasizing Nonvulvar Locations, Variant Histology, and Prognostic Factors

We report 27 solitary fibrous tumors of the female genital tract emphasizing nonvulvar locations, variant histology, and prognostic factors. The patients ranged from 25 to 78 years (most were over 40), and tumors occurred in the vulva (7), vagina (2), cervix (2), corpus (6), fallopian tube/paratubal soft tissue (5), and ovary (5). They ranged from 1.5 to 39 (mean=10.5) cm and were typically solid, but 4 were predominantly cystic. All had a haphazard arrangement of spindled to ovoid cells, with most demonstrating alternating cellular and hypocellular areas and prominent vessels, but 13 lacked hypocellular areas, and 7 had focal diffuse growth with inconspicuous vasculature. Other patterns included corded (8), fascicular (5), trabecular (1), and nested (1). Microcysts (6), myxoid background (8), hyalinization (8), lipomatous differentiation (2), and multinucleated cells (6) were also present, and 10 tumors had necrosis. Vasculature included thin-walled branching "staghorn" (27), thick-walled (7), and hyalinized vessels (5) or dilated anastomosing vascular channels (3). Nuclear atypia ranged from mild (19), moderate (7), to severe (1), and mitoses from 0 to 24/10 HPF (mean=4). STAT6 was positive in all 25 tumors tested. One tumor showed dedifferentiation; the remainder were classified as benign (19) or malignant (7) based on mitotic rate (univariate stratification model) and as low risk (14), intermediate risk (8), or high risk (4) based on the Demicco multivariate risk stratification score. Follow-up (median=23 mo) was available for 16 patients. Six tumors recurred (2 intermediate risk, 3 high risk, and the dedifferentiated tumor), 5 in the abdomen; the dedifferentiated tumor metastasized to the lung. Multivariate risk stratification was superior to univariate classification, as 5 "benign" tumors were reclassified as intermediate risk using the multivariate model; of these, 2 recurred, and 1 patient died of disease. Upper female genital tract tumors occurred in older patients, were larger, and more frequently classified as high risk compared with those of the lower tract. A trend toward increased cellularity was also seen in the upper tract tumors. Only size (P=0.04), necrosis (P=0.04), and Demicco score (P=0.01) independently correlated with recurrence. Female genital tract solitary fibrous tumors demonstrate a wide range of variant morphologies and occur in diverse sites in addition to the vulva. Tumors were often misdiagnosed as other neoplasms; thus, awareness of solitary fibrous tumors occurring at these sites is crucial in prompting staining for STAT6 to establish this diagnosis. The Demicco risk stratification system effectively predicts behavior.

Mesenchymal lesions of the vulva

Mesenchymal lesions of the vulva include site-specific entities limited to the lower genital tract, as well as a range of non-site-specific tumors that are more common at extragenital sites. Site-specific lesions include fibroepithelial stromal polyp, cellular angiofibroma, angiomyofibroblastoma, and aggressive angiomyxoma. Non-site-specific tumors that may occur in the vulva include those of smooth muscle, skeletal muscle, vascular, neural, adipocytic, and uncertain differentiation. This review discusses both site-specific and non-site-specific vulvar mesenchymal lesions including non-neoplastic proliferations, benign neoplasms, locally aggressive neoplasms with a predilection for local recurrence, neoplasms of indeterminate biologic potential, and frankly malignant neoplasms with a high risk of distant metastasis and death. Accurate diagnosis is essential for proper management, and is facilitated by correlation with clinical findings and targeted application of immunohistochemical and molecular studies.

Cytomorphologic features of malignant solitary fibrous tumor with mediastinal involvement sampled by endoscopic and endobronchial ultrasound-guided fine-needle aspiration: A comparison of two cases

Solitary fibrous tumor (SFT) is an uncommon fibroblastic neoplasm with considerable risk of local recurrence. SFT is histologically characterized by bland spindled-to-epithelioid cells in alternating hyper- and hypocellular zones, a "patternless pattern," ectatic "staghorn" vessels with variable edematous perivascular stroma, and thick ropey collagen. Cytologically, smears are variably cellular with spindled-to-epithelioid cells with oval nuclei, wispy cytoplasm, multiple inconspicuous nucleoli, and occasional nuclear pseudoinclusions. Small vessels and bare/stripped nuclei are generally present while mild atypia is not uncommon. STAT6 nuclear expression is the most useful immunohistochemical stain and is the product of a NAB2-STAT6 gene fusion. SFTs with mediastinal involvement may be diagnostically challenging due to proximity to vital structures and anticipated patient risks. Endobronchial and endoscopic ultrasound-guided fine-needle aspiration (EBUS/EUS-FNA) are minimally-invasive tissue sampling methods that provide diagnostic material while minimizing patient risk, and the mediastinum is accessible by both procedures. Small aspirate samples and SFT nonspecific features can compound the diagnostic difficulty, although familiarity with the cytologic, morphologic, immunophenotypic, and genetic features of SFTs assist the pathologist in confirming the diagnosis. Pathologists must also be aware of high-risk SFT features to ensure appropriate therapy and management. Case #1 describes a recurrent mediastinal SFT with high-risk features sampled by EUS-FNA. Case #2 describes a primary diagnosis of mediastinal SFT with malignant behavior made on an EBUS-FNA specimen.

A broad ligament solitary fibrous tumor with Doege-Potter syndrome

INTRODUCTION

Solitary fibrous tumors (SFTs) are uncommon mesenchymal neoplasms and are particularly rare in the female genital tract. Doege-Potter syndrome is a paraneoplastic syndrome involving SFT-associated hypoglycemia. We report, for the first time, on a broad ligament SFT with Doege-Potter syndrome; additionally, we review 30 cases of women with SFTs reported in the literature.

PATIENT CONCERNS

A 37-year-old woman who presented with life-threatening hypoglycemia and a pelvic mass (16 × 15 × 15 cm).

DIAGNOSES

The patient was diagnosed with broad ligament SFT with Doege-Potter syndrome.

INTERVENTIONS

Tumor resection, sub-extensive hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymphadenectomy were performed, and 6 cycles of adjuvant chemotherapy were administered.

OUTCOMES

Serum glucose levels returned to normal as soon as the tumor was resected. Forty-3 months after operation, there was recurrence in the posterior peritoneal tissues. She underwent tumor resection and has remained tumor-free 28 months after this excision.

CONCLUSION

Even though it is extremely rare, SFT should be quickly identified to prevent undue treatment delay and avoid unnecessary examination; surgery and long-term follow-up are recommended. SFT can be considered a highly invasive cancer, and intraoperative bleeding may occur. Although no correlation between adjuvant therapy and improved prognosis was found, further studies are required because of the small number of cases reported to date.

Solitary Fibrous Tumor of the Vagina

Solitary fibrous tumor, initially described in the pleura, is now known to occur in various extrathoracic sites. However, its occurrence in the female genital tract, especially the vagina, is extremely rare. The authors report here a case of a well-circumscribed vaginal spindle cell nodule in a 48-year-old woman with features consistent with solitary fibrous tumor. The diagnosis was established histologically by the varying pattern with hypocellular fibrous areas alternating with hypercellular areas and hemangiopericytoma-like areas and, immunohistochemically by the strong positive reaction for CD34 and Bcl2 with a negative reaction for all other spindle cell and epithelial markers. The differential diagnosis is discussed and a review of the literature is presented.

Miscellaneous Pseudotumors and Mesenchymal Tumors of the Female Genital Tract

Benign and malignant soft tissue tumors and pseudotumors can rarely arise anywhere in the female genital tract. Their pathologic features as well as behavior typically overlap with those described in tumors involving typical locations. However, due to their rarity, not infrequently these tumors represent a diagnostic challenge. Their diagnosis should be based on careful gross examination, thorough sampling, and morphologic evaluation, applying a selected immunohistochemical panel and molecular studies. Accurate classification of these tumors is important because their clinical behavior, prognosis, and therapy differ markedly. This article outlines several mesenchymal lesions reported in the female genital tract, encompassing recent histologic, immunohistochemical, and molecular findings, with special emphasis on problems in the differential diagnosis.