Patterns of adjuvant therapy for endometrial cancer: single institutional experience in Thailand.

Aim: The aim of this study was to evaluate the use of adjuvant therapy and treatment outcomes in patients with endometrial cancer (EMC).

Methods: Patients with EMC treated in the institution were identified. Data collected were age, stage of disease, histopathology, and adjuvant therapy. Progression-free survival (PFS) and overall survival (OS) were studied.

Results: The median age of 383 patients was 57 years (30-86 years). Majority had early-stage diseases (76.5%), endometrioid histopathology (87.2%), and high-grade tumors (74.9%). Less than half (44.4%) had adjuvant therapy. Pelvic radiation was the most common type of adjuvant treatment. We found that 25.7% of stages III to IV patients did not have adjuvant therapy (mainly from old age or poor performance status). On the other hand, 21.5% of patients with stage IA had adjuvant treatment (owing to risk factors or other synchronous cancers). The 5-year PFS and 5-year OS (95% confidence interval) were 84.3% (80.5%-88.1%) and 81.2% (77.1%-85.4%), respectively. Significant prognostic factors for survival by univariable analyses were stage, tumor grade, and histopathology. By multivariable analyses, significant prognostic factors were stage, tumor grade (only for OS), histopathology, and adjuvant therapy. Focusing on stage and adjuvant therapy, we found that the PFS and OS of early-stage patients who had or did not have adjuvant therapy were not significantly different, whereas the PFS and OS of advanced-stage patients who had adjuvant treatment were significantly higher than the PFS and OS of those who did not have adjuvant treatment.

Conclusions: The use of adjuvant therapy for patients with EMC was not according to the standard recommendation in all patients for many reasons. The benefit of adjuvant therapy was demonstrated in advanced- but not in early-stage cancer.