Early stage uterine papillary serous carcinoma of the endometrium: effect of adjuvant whole abdominal radiotherapy and pathologic parameters on outcome

Abstract

Background: Uterine papillary serous carcinoma (UPSC) is an aggressive subtype of endometrial cancer, behaving like ovarian epithelial cancers and having a predilection for transperitoneal relapse. Within this subtype of uterine cancers, predictors of outcome and the role of adjuvant therapies have not been firmly established, to the authors' knowledge.

Methods: Between 1985-1995, 78 patients who had International Federation of Gynecology and Obstetrics (FIGO) Stage I, II, or IIIa UPSC (based on positive washings only) were seen at the British Columbia Cancer Agency. During this time, the authors had a policy of offering adjuvant pelvic, paraaortic and whole-abdominal radiotherapy (WART) to these patients. Fifty-eight patients received adjuvant WART, and 20 received lesser or no adjuvant therapy. The authors undertook a retrospective analysis of pathology with quantification of the percentage of papillary serous component (% PSC) and p53 expression. Pathology was retrieved and reviewed on 62 patients; p53 staining was performed on blocks from the hysterectomy specimen in 46 cases. Pathologic parameters, stage, and adjuvant therapy were correlated with clinical outcome in a multivariate analysis.

Results: Median follow-up was 52 months (3-139 mos) and the 5-year disease-specific survival rate was 66.2%. The 58 patients who received adjuvant WART had a significantly better 5-year disease-specific survival than those 20 patients who did not, 74.9% versus 41.3% (P = 0.04). Multivariate analysis showed that % PSC and p53 were not significant predictors of outcome for early stage UPSC. Of the factors examined, only FIGO stage and WART significantly predicted improved outcome (P = 0.02 and 0.04, respectively).

Conclusions: The current study demonstrated a significant difference in the outcomes of patients who had FIGO Stage I compared with Stage II UPSC. In the current series of patients, the authors were not able to predict outcome based on % PSC or p53 expression. The current study results with WART were promising, and WART merits further study.