Oncologic outcomes of incidental serous tubal intraepithelial carcinoma and associated high-grade serous carcinoma in high-risk patients undergoing risk-reducing surgery.

Objective: We sought to describe the oncologic outcomes of isolated serous tubal intraepithelial carcinomas compared to an intraepithelial carcinoma found concurrently with microscopic high-grade serous carcinoma among patients with hereditary predisposition to ovarian cancer who underwent risk-reducing surgery.

Methods: We conducted a retrospective analysis of 32 high-risk patients with BRCA1, BRCA2, RAD51C/D, BRIP1, or PALB2 pathogenic variants who were diagnosed with either isolated serous tubal intraepithelial carcinoma or concurrent serous tubal intraepithelial carcinoma and microscopic high-grade serous carcinoma following risk-reducing surgery between January 2006 and December 2023. Our population included patients who underwent surgery at our institution as well as those who had surgery elsewhere, but sought second opinions, follow-up care, or treatment at our institution. Data were gathered from medical and pathologic records, and pathologic specimens were re-reviewed by a gynecologic pathologist. Standard statistical methods were used to describe oncologic outcomes per group.

Results: Among 32 patients in the cohort, we found that 68.7% had a pathologic diagnosis of an incidental serous tubal intraepithelial carcinoma, while 31.3% had a pathologic diagnosis of microscopic high-grade serous carcinoma with associated serous tubal intraepithelial carcinoma. Notably, two patients (9%) with isolated serous tubal intraepithelial carcinoma developed primary peritoneal carcinoma within a median of 29 months after surgery. One-third of patients with microscopic cancer experienced recurrence despite receiving standard staging surgery and chemotherapy for early-stage disease. Most of the patients in the cohort were older at the time of risk-reducing surgery than recommended for their pathologic variant.

Conclusions: The study supports the critical need for timely risk-reducing surgery in high-risk populations, as well as a comprehensive pathologic examination along with vigilant post-operative surveillance. Consensus guidelines for management of serous tubal intraepithelial carcinoma are necessary to identify a group of patients at higher risk of progression to primary peritoneal carcinoma and optimize patient care.