OBJECTIVETo study the clinicopathologic features of primitive neuroectodermal tumor (PNET) in female genital tract.

METHODSSix cases of PNET arising in female genital tract were retrospectively reviewed. The clinicopathologic features, immunohistochemical findings and EWS gene translocation study results were analyzed.

RESULTSThe age of patients ranged from 10 to 27 years (mean = 20 years). The sites of involvement included ovary (1 case), uterus (1 case), vulva (2 cases) and vagina (2 cases). The greatest diameter of the tumor ranged from 2 to 10 cm (mean = 5.4 cm). The tumor had nodular appearance and showed grayish-pink fleshy cut surface, accompanied by foci of hemorrhage and necrosis. Histologically, the tumor was composed of malignant small round cells with indistinct cell borders, hyperchromatic nuclei, dense chromatin, tiny nucleoli and scanty cytoplasm. The tumor cells were arranged in sheets or lobules. Homer-Wright rosettes were identified in 1 case. Immunohistochemical study showed that the tumor cells were positive for CD99, FLI-1 and CD56 (6/6). Focal expression of vimentin (5/6), NSE (5/6), nestin (4/6), synaptophysin (4/6), S-100 protein (2/6) and chromogranin A (1/6) was also demonstrated. EWS gene translocation was detected in 5 cases studied. Follow-up information was available in 2 patients (7 and 17 months of follow up, respectively). One of them died of tumor metastasis 17 months after diagnosis. The other patient was still alive.

CONCLUSIONSPNET arising in female genital tract is rare. It mainly involves ovary, uterus, vulva and vagina. Immunohistochemical study using a panel of antibodies and fluorescence in-situ hybridization play an important role in definitive diagnosis of this rare malignancy.

12E7 Antigen ; Adolescent ; Adult ; Antigens, CD ; metabolism ; CD56 Antigen ; metabolism ; Cell Adhesion Molecules ; metabolism ; Child ; Female ; Follow-Up Studies ; Genital Neoplasms, Female ; genetics ; metabolism ; pathology ; surgery ; Humans ; Neuroectodermal Tumors, Primitive, Peripheral ; genetics ; metabolism ; pathology ; surgery ; Ovarian Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Proto-Oncogene Protein c-fli-1 ; metabolism ; RNA-Binding Protein EWS ; genetics ; Retrospective Studies ; Translocation, Genetic ; Uterine Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Vaginal Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Vimentin ; metabolism ; Vulvar Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Young Adult

Cyclin-Dependent Kinase Inhibitor p16 ; metabolism ; Cystadenocarcinoma, Serous ; metabolism ; pathology ; Diagnosis, Differential ; Endometrial Neoplasms ; metabolism ; pathology ; Female ; Humans ; Precancerous Conditions ; metabolism ; pathology ; RNA-Binding Proteins ; metabolism ; Tumor Suppressor Protein p53 ; metabolism

Adaptor Proteins, Signal Transducing ; genetics ; Animals ; Female ; Fertilization ; Humans ; Hydatidiform Mole ; genetics ; pathology ; Karyotyping ; Male ; Mosaicism ; Mutation ; Pregnancy ; Spermatozoa ; Uterine Neoplasms ; genetics ; pathology

Antibodies, Monoclonal ; therapeutic use ; Antibodies, Monoclonal, Humanized ; Antineoplastic Agents ; therapeutic use ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; genetics ; metabolism ; pathology ; Cetuximab ; Gene Rearrangement ; Humans ; Lung Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Mutation ; Oncogene Proteins, Fusion ; genetics ; metabolism ; Phosphorylation ; Precision Medicine ; Proto-Oncogene Proteins ; genetics ; metabolism ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism ; Proto-Oncogene Proteins p21(ras) ; Receptor Protein-Tyrosine Kinases ; genetics ; metabolism ; Receptor, Epidermal Growth Factor ; genetics ; metabolism ; ras Proteins ; genetics ; metabolism

Cyclin D1 ; metabolism ; Gene Rearrangement ; Germinal Center ; metabolism ; pathology ; Humans ; Lymphoma ; genetics ; metabolism ; pathology ; Lymphoma, Follicular ; genetics ; metabolism ; pathology ; Lymphoma, Mantle-Cell ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins c-bcl-2 ; metabolism

Breast Neoplasms ; pathology ; radiotherapy ; surgery ; Diagnosis, Differential ; Female ; Hemangiosarcoma ; etiology ; pathology ; surgery ; Humans ; Iatrogenic Disease ; Neoplasm Recurrence, Local ; Neoplasms, Radiation-Induced ; etiology ; pathology ; surgery ; Vascular Diseases ; etiology ; pathology ; surgery

Alveolar Epithelial Cells ; pathology ; Diagnosis, Differential ; Humans ; Hyperplasia ; diagnostic imaging ; etiology ; metabolism ; pathology ; Lung Diseases ; diagnostic imaging ; etiology ; metabolism ; pathology ; Mucin-1 ; metabolism ; Nuclear Proteins ; metabolism ; Radiography ; Thyroid Nuclear Factor 1 ; Transcription Factors ; metabolism ; Tuberous Sclerosis ; complications ; diagnostic imaging ; metabolism ; pathology

12E7 Antigen ; Antigens, CD ; metabolism ; Cell Adhesion Molecules ; metabolism ; Diagnosis, Differential ; Fibrosarcoma ; metabolism ; pathology ; Heart Neoplasms ; genetics ; metabolism ; pathology ; surgery ; Humans ; Male ; Mesothelioma ; genetics ; metabolism ; pathology ; Middle Aged ; Mucin-1 ; metabolism ; Oncogene Proteins, Fusion ; metabolism ; Pericardiectomy ; Pericardium ; pathology ; Sarcoma ; metabolism ; pathology ; Sarcoma, Synovial ; genetics ; metabolism ; pathology ; surgery ; Translocation, Genetic ; Vimentin ; metabolism

Antigens, Nuclear ; metabolism ; Cordotomy ; methods ; Diagnosis, Differential ; Ependymoma ; metabolism ; pathology ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Nerve Tissue Proteins ; metabolism ; Neurocytoma ; metabolism ; pathology ; surgery ; Oligodendroglioma ; S100 Proteins ; metabolism ; Spinal Cord Neoplasms ; metabolism ; pathology ; surgery ; Synaptophysin ; metabolism

Antigens, CD20 ; metabolism ; CD79 Antigens ; metabolism ; Carcinoma, Neuroendocrine ; metabolism ; pathology ; Carcinoma, Renal Cell ; metabolism ; pathology ; Diagnosis, Differential ; Female ; Follow-Up Studies ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; Leukocyte Common Antigens ; metabolism ; Lymphoma, Large B-Cell, Diffuse ; metabolism ; pathology ; Middle Aged ; Neoplasms, Multiple Primary ; metabolism ; pathology ; Nephrectomy ; PAX5 Transcription Factor ; metabolism ; Wilms Tumor ; metabolism ; pathology