The detrimental effect of adopting interval debulking surgery in advanced stage low-grade serous ovarian cancer

Objective: To examine outcomes of patients having treatments for newly diagnosed advanced stage low-grade serous ovarian cancer (LGSC). Methods: We conducted a retrospective case series of women affected by advanced stage (stage IIIB or more) LGSC undergoing surgery in a single oncologic center between January 2000 and December 2017. Survival outcomes were assessed using Kaplan-Meier and Cox models. Results: Data of 72 patients were retrieved. Primary cytoreductive surgery was attempted in 68 (94.4%) patients: 19 (27.9%) had residual disease (RD) > 1 cm after primary surgery. Interval debulking surgery (IDS) was attempted in 15 of these 19 (78.9%) patients and the remaining 4 patients having not primary debulking surgery. Twelve out of 19 (63.1%) patients having IDS had RD. After a mean (±standard deviation) follow-up was 61.6 (±37.2) months, 50 (69.4%) and 22 (30.5%) patients recurred and died of disease, respectively. Via multivariate analysis, non-optimal cytoreduction (hazard ratio [HR]=2.79; 95% confidence interval [CI]=1.16-6.70; p=0.021) and International Federation of Obstetrics and Gynecologists (FIGO) stage IV (HR=3.15; 95% CI=1.29-7.66; p=0.011) were associated with worse disease-free survival. Via multivariate analysis, absence of significant comorbidities (HR=0.56; 95% CI=0.29-1.10; p=0.093) and primary instead of IDS (HR=2.95; 95% CI=1.12-7.74; p=0.027) were independently associated with an improved overall survival. Conclusion: LGSC is at high risk of early recurrence. However, owing to the indolent nature of the disease, the majority of patients are long-term survivors. Further prospective studies and innovative treatment modalities are warranted to improve patients care.