[Clinicopathological features of mixed cervical carcinoma with adenoid cystic pattern]

Objective: To investigate the clinicopathological characteristics, immunophenotype, molecular characteristics, differential diagnosis, clinical treatment and prognosis of mixed carcinoma of cervix with adenoid cystic pattern. Methods: Three cases of mixed cervical carcinoma with adenoid cystic pattern were collected at the Affiliated Hospital of Xuzhou University Medical School from 2018 to 2021.The clinicopathological characteristics were analyzed, immunohistochemistry (IHC) and in situ hybridization (ISH) were performed. The related literature was reviewed. Results: The three patients were postmenopausal women with a median age of 74.7 years. The clinical symptom was vaginal bleeding without obvious causes. One case was an endophytic tumor, and the others were exophytic. The median diameter of the three cases was 3.3 cm. Two patients underwent hysterectomy, the tumors infiltrated the external 1/3 and middle 1/3 of the cervix respectively. All the lymph nodes were negative. One patient had a previous biopsy. Microscopically, all three tumors were characterized by a cribriform structure, which were filled with basophilic myxoid substance and surrounded by tubules lined by two layers of cells. The tumor cells had scanty cytoplasm and showed the characteristics of cervical basal-like cells. All three cases were accompanied by high-grade squamous intraepithelial lesions and squamous cell carcinoma, and one also showed a non-specific spindle cell sarcomatoid component. Within the double-layered epithelial structure, the outer epithelium was positive for p63, CD117, p16^INK4a (clone E6H4) and MYB protein and negative for S-100 by IHC. The combined positive score of PD-L1 (clone 22C3) was less than 1 in all three cases. Human papillomavirus (HPV) types 16 and 18 were detected in one patient preoperatively, while high-risk HPV were positive in the other two patients by RNAscope ISH postoperatively. None of the three cases showed MYB gene rearrangement by FISH. The mean follow-up time was 23.3 months (36, 28 and 6 months, respectively). Two patients underwent hysterectomy and radiotherapy survived without disease. One patient survived with tumor just by radiotherapy and drug therapy. Conclusions: Mixed cervical carcinoma with adenoid cystic pattern is extremely rare. It is a high-grade malignancy with poor prognosis. The tumor is associated with high-risk HPV infection, without MYB gene rearrangement, and with low PD-L1 immunoreactivity. Radical surgery combined with radiotherapy and chemotherapy is the mainstay of treatment at present.