The challenge of managing isolated STIC lesions: A single-center experience

High-grade serous carcinoma (HGSC) arise from serous tubal intraepithelial carcinoma (STIC) lesions, a precursor that develops from the fallopian tube epithelium. Patients with incidental isolated STIC lesions found on salpingectomy specimen have up to 25% risk of developing HGSC or peritoneal carcinomatosis in the future, yet there is no established consensus to guide management.

This retrospective case series includes patients diagnosed with isolated STIC lesions between April 2017 and January 2024. Patient data was extracted from clinical and pathological databases.

During the study period, 10 patients were diagnosed with an isolated STIC lesion. The fallopian tubes were removed either as part of a hysterectomy for endometrial cancer (n = 3); a prophylactic risk-reducing surgery for BRCA1 or BRCA2 mutation (n = 3); or a benign gynecologic condition (n = 4). The median age of the patients was 64 years (range: 53-80). Among patients who underwent genetic testing (n = 9), only three were found to have a deleterious germline mutation in BRCA1 or BRCA2. The patients either received adjuvant chemotherapy (n = 5) or underwent active surveillance (n = 5). One surveillance patient was managed with completion bilateral oophorectomy and omentectomy. Median number of chemotherapy cycles was four (range 4-6 cycles). The median follow-up was 27 months (range: 5-83 months). One patient under active surveillance was diagnosed with peritoneal carcinomatosis 5 years after initial diagnosis of STIC whereas none recurred in the chemotherapy group.

The wide variety of treatment approaches we observed highlights a need for more data on this entity to support management guidelines.