Case Report: Coexistence of Adenoid Cystic Carcinoma and Adenoid Basal Carcinoma in the Uterine Cervix

Abstract

Abstract Introduction/Objective Adenoid cystic carcinoma (ACC) and adenoid basal carcinoma (ABC) are very rare tumors, accounting for less than 1% of all cervical adenocarcinomas. ACC is an aggressive neoplasm and has poor prognosis while ABC has a favorable prognosis. Coexistence of ACC or ABC and squamous intraepithelial lesion/invasive squamous cell carcinoma in the uterine cervix has been reported in the literature; however, coexistence of ACC and ABC in the uterine cervix is very rare. Methods Case presentation: Here we present a case of coexistence ACC and ABC in a 66-year-old woman who suffered from heavy bloody vaginal discharge for one year with weight fluctuations. The cervical exam and CT scan showed a friable mass at the uterine cervix, measuring up to 5.5 cm, and cervical mass punch biopsy was performed. Histopathological examination of the specimen revealed an intact nonkeratinizing stratified squamous epithelium overlying proliferation of nests punctuated by small round spaces, resembling cribriform pattern in the stroma. The tumor cells were small and basaloid with hyperchromatic nuclei and scant cytoplasm. Palisading of tumor cells at the peripheral of the tumor nests were observed in some areas. Mitotic figures and necrosis were not seen. Immunohistochemical stains were performed and showed two distinct patterns of ACC and ABC. ACC tumor cells were positive for CD117, focally positive for CAM5.2 and S100, and negative for p63. ABC tumor cells were positive for p63 and EMA and negative for CD117 and S100. Both ACC and ABC components were positive for p16, Sox 10, BCL-2 and vimentin and negative for CK7, p40, CEA and ER. PAS stain showed positive staining in the basement membrane-like material in ACC component. A final pathologic diagnosis of coexistence of ACC and ABC of the uterine cervix were made. Conclusion Literature review revealed that this was an exceedingly rare case of coexistence of ACC and ABC in the uterine cervix. It is extremely important to correctly diagnose ACC and ABC as there is very poor prognosis in the former and good prognosis in the latter.