RESUMEN
El tumor fibroso solitario (TFS) es una neoplasia mesenquimatosa de tipo fibroblástico que, a pesar de ser localizado principalmente en pleura, se ha observado en otros órganos como la próstata. Por su parte, el tumor fibroso solitario de la próstata es una neoplasia de baja incidencia, crecimiento lento y potencial maligno incierto, que generalmente se compone de células fusiformes de apariencia citológicamente benignas, dispuestas en una arquitectura desorganizada, mezcladas con colágeno y pequeños vasos sanguíneos. Establecer su diagnóstico se ha vuelto más reproducible desde la identificación de la fusión de los genes NAB2-STAT6 por biología molecular, que lleva a la sobreexpresión de STAT6 por inmunohistoquímica, el cual es un marcador muy sensible y específico para TFS. Presentamos el caso clínico de un paciente que debutó con síntomas de compresión vesical, en quien se identificó una masa con epicentro en la próstata que infiltraba la vejiga y llegaba a la pared rectal, y que luego de estudios de patología, inmunohistoquímica y pruebas moleculares se clasificó como un TFS de la próstata, finalmente tratado con cistoprostatectomía radical más derivación urinaria
Solitary fibrous tumor (SFT) is a mesenchymal neoplasm of fibroblastic type, which despite being located mainly in the pleura, has been observed in other organs such as the prostate. On the other hand, solitary fibrous tumor of the prostate is a rare neoplasm, slow growing, and of uncertain malignant potential, which is generally composed of spindle cells of cytologically benign appearance, arranged in a disorganized architecture, mixed with collagen and small blood vessels. Establishing its diagnosis has become more reproducible since the identification of the NAB2-STAT6 gene fusion by molecular biology, leading to the overexpression of STAT6 by immunohistochemistry, a very sensitive and specific marker for SFT. We present a clinical report of a patient who consulted with symptoms of bladder compression, in whom a mass was identified with the epicenter in the prostate infiltrating into the bladder and reaching the rectal wall. Following histopathology study, immunohistochemistry and molecular tests it was classified as a SFT of the prostate, finally treated with radical cystoprostatectomy plus urinary shunt
Asunto(s)
Humanos , Próstata , Prostatectomía , Neoplasias de la Próstata , Factor de Transcripción STAT6 , Tumores Fibrosos SolitariosRESUMEN
Objective@#To investigate the clinical manifestations, imaging features, clinicopathologic features, and differential diagnosis of solitary fibrous tumors/anginoblastomas (SFT/HPCs) originating in the central nervous system.@*Methods@#Sixty cases of SFT/HPCs originating in the central nervous system were collected at Nanjing Jinling Hospital, from January 1, 2008 to December 31, 2016. The clinical data, imaging data, histomorphologic changes and immunohistochemical finding were analyzed in the sixty cases.@*Results@#The 60 cases included 26 males and 34 females, aged 14 to 85 (median 49) years. The main clinical manifestations were headache, dizziness with nausea and vomiting. Radiologically, the tumors were large, enhancing, solid and cystic masses attached to the dura. Histopathologically, the neoplasms were composed of spindle cells with oval nuclei, inconspicuous nucleoli and moderate amount of eosinophilic cytoplasm arranged in fascicles with areas of hyalinized stroma, myxoid changes and a staghorn vascular pattern. Immunohistochemically, tumor cells of all cases were positive for vimentin (100.0%, 60/60), STAT6 (98.3%, 59/60), CD34 (61.7%, 37/60), and the tumor cells were typically positive for CD99, bcl-2, EMA and SSTR2 as well.Negative for S-100 protein, SOX10, E-cadherin, GFAP. Ki-67 index ranged from 1% to 50%. Forty cases were followed up for 6 to 82 months with average of 40 months, 30 patients were alive and 10 patients died.@*Conclusions@#Central nervous system SFT/HPCs can be aggressive and relapses may occur several years after diagnosis. STAT6 is highly sensitive and specific for the diagnosis. Complete tumor resection is optional treatment followed by radiotherapy and chemotherapy. There is a correlation between the prognosis and the location of the disease, the histological grade, Ki-67 index, and fusion gene variants.
RESUMEN
Objective@#To investigate the clinicopathologic characteristics, immunophenotypes, and differential diagnostic features of extra-pleural solitary fibrous tumor (SFT) with uncommon histology.@*Methods@#Seven cases of extra-pleural SFT with uncommon histology were collected during January 2015 and December 2016 in Zhejiang Provincal People′s Hospital; the clinical and radiologic features, histomorphology, immunophenotype and prognosis were analyzed. EnVision method was used for immunohistochemical staining of STAT6, CD34 and other differential diagnosis associated markers.@*Results@#There were five male and two female patients, age from 23 to 54 years (mean=39 years). Three tumors were located in the soft tissue of head and neck, two in trunk subcutaneous soft tissue, one in sella region, and one in the kidney. Grossly the tumors ranged from 0.4 to 8.0 cm (mean=3.1 cm). Microscopically, all three head and neck cases resembled giant cell angiofibroma/giant cell subtype SFT, and one case showed sheet-like pattern of the multinucleated syncytial cells, creating a biphasic arrangement similar to myofibroma. Both truncal tumor resembled lipomatous type SFT, with one similar to dermatofibrosarcoma protuberans and the other to atypical spindle cell lipomatous tumor. The sella tumor showed morphology of a conventional SFT with high grade sarcomatous transformation. The renal tumor demonstrated a malignant SFT with entrapped benign renal tubules, mimicking a biphase synovial sarcoma or a malignant mixed epithelial and stromal tumor. By immunohistochemistry, all seven SFTs showed diffuse and strong nuclear reactivity to antibody against STAT6.@*Conclusions@#Extra-pleural SFTs show a significant heterogeneity of morphology and biological behavior which could cause differential confusion.Careful attention to its characteristic histomorphology with the use of STAT6 immunohistochemistry can help distinguish this tumor from its many mimickers.
RESUMEN
Objective@#To study the clinicopathologic features, the differential diagnosis and the expression of STAT6 in solitary fibrous tumor (SFT).@*Methods@#Eighty cases of SFT were evaluated. The expression of STAT6, CD34, CD99 and bcl-2 protein was studied in these cases and in other groups of soft tissue tumors by immunohistochemical EnVision method. The results were analyzed and relevant literature were reviewed.@*Results@#The expression rate of STAT6 in SFT was 97.5% (78/80) and that in other soft tissue tumors was 3.3% (3/90). The difference was significant (P<0.05). The expression rates of CD34, CD99 and bcl-2 were 88.8% (71/80), 76.3% (61/80) and 75.0% (60/80) in SFT, respectively, which were significantly different from STAT6 expression rate (P<0.05).@*Conclusions@#The expression of STAT6 in SFT has high sensitivity (97.5%) and specificity (96.7%). The expression of STAT6 in SFT is higher than that of CD34, CD99 and bcl-2. STAT6 may be a useful marker for clinical diagnosis of SFT.