Primary primitive neuroectodermal tumor of the cervix confirmed with molecular analysis in a pregnant woman: A case report and literature review

Abstract

Primary primitive neuroectodermal tumor (PNET) in the female tract is rare. Recently, a case of cervical PNET was diagnosed in our hospital. A 29-year-old pregnant woman presented with a cystic-solid cervical mass at the 7th week of gestation. The mass grew rapidly during follow-up and ruptured at the 22nd week. A biopsy was performed on the mass. Pathological examination revealed a malignant neoplasm composed of small cells which exhibited positive immunohistochemical (IHC) staining for CD99, SYN, and FLI1. Fluorescence in situ hybridization (FISH) displayed the presence of EWS-FLI1 fusion gene resulting from the chromosomal translocation t (11;22, q24;q12), which confirmed the diagnosis of cervical PNET. The reverse transcription-polymerase chain reaction (RT-PCR) results showed type 2 EWS-FLI1 fusion occurred in this tumor, suggesting a poor prognosis. The patient underwent surgical resection and was given adjuvant chemotherapy followed by pelvic radiotherapy. PNET arising from the genital tract, especially in the uterine cervix, is very rare and presents a diagnostic challenge. FISH and RT-PCR analysis are helpful for the diagnosis of such a tumor at an unusual site, as in the present case.

Ewing Sarcoma of the Female Genital Tract

“…Rare reports are associated with pregnancy. [31][32][33] Occasionally, immunohistochemistry is the sole adjunct to morphology, wherein intense membranous CD99 is an invariable staple, bolstered by positivity for any of FLI1 (highly nonspecific and not recommended for this purpose) and (more recently) NKX2.2. Variant morphology is infrequently reported in gynecologic Ewing sarcoma, manifested in a subset of cells that otherwise display conventional small round cell appearance: spindle cell fascicles, rhabdoid/plasmacytoid cytology, cytoplasmic clearing, and "adamantinoma-like" epithelial differentiation.…”

“…Unfortunately, about a third succumb to their disease quite rapidly, with relentless progression on therapy and death within < 1 year. [16][17][18]22,31,32, Despite advancements, Ewing sarcoma is still often considered a malignancy of the young, heralded by suspicious preoperative musculoskeletal radiology, which in many cases is tantamount to diagnostic. Nonetheless, the literature has expanded to progressively encompass more mature populations, which in said peculiar circumstances has conceivably rendered misdiagnosis and suboptimal preoperative treatment.…”

“…Primary site of disease is most heavily represented by the uterine corpus and cervix, followed by the vulvovaginal tract, and finally, the upper genital tissues (ovary>fallopian tube>broad ligament). Rare reports are associated with pregnancy 31–33 . Occasionally, immunohistochemistry is the sole adjunct to morphology, wherein intense membranous CD99 is an invariable staple, bolstered by positivity for any of FLI1 (highly nonspecific and not recommended for this purpose) and (more recently) NKX2.2.…”

“…Treatment is adjuvant chemotherapy per standard Ewing sarcoma protocols administered at other sites, and more than half of patients are treated surgically and/or chemotherapeutically to no evidence of disease after several months to years of surveillance. Unfortunately, about a third succumb to their disease quite rapidly, with relentless progression on therapy and death within <1 year 16–18,22,31,32,34–61 …”