Complete cytoreduction: Is epithelial ovarian cancer confined to the pelvis biologically different from bulky abdominal disease?

Objectives. The aim of this study was to determine whether site and size of tumor masses prior to complete surgical cytoreduction affect outcome survi val. Methods. A retrospective review was performed of 53 women with stage II and III epithelial ovarian cancer following complete surgical cytoreduction. Results. Fifteen cases (28%) were classified as stage II and the remaining 38 cases (72%) as stage III. The overall median survival was 58 months with overall 2- and 5-year survivals of 76 and 42%, respectively. On univariate analysis, women with well differentiated tumors did significantly better t han those with moderately or poorly differentiated tumours (P = 0.0009). FI GO stage did not reach statistical significance (P = 0.066). On multivariat e analysis, comparing patient's age, previous history of pelvic surgery, pr evious history of malignancy, performance of lymphadenectomy for visibly/pa lpably enlarged nodes, performance of bowel resection, presence of concomit ant tumors, positive pelvic and/or paraaortic lymph nodes, histological typ e, histological grade, and FIGO stage, only histological grade remained an independent variable affecting outcome survival (P = 0.0004; FIGO stage, P = 0.22) (hazard ratio = 6.5: well versus poor differentiation, 95% confiden ce interval, 1.7-25.5). Conclusion. When surgical cytoreduction to no visible disease has been achi eved in women with stage II and III epithelial ovarian cancer, FIGO stage, i.e., site and size of tumor masses prior to surgical cytoreduction, does n ot appear to influence outcome survival. The aggressiveness of the remainin g microscopic disease would seem to be determined largely by histological g rade. Bearing in mind the retrospective nature of this study and the relati vely small cohort of patients, the results would appear to suggest that it is unlikely that there are any other significant parameters (hidden factors ) affecting tumor biology which are independent of tumor grade in these pat ients. A possible implication of this result is that complete surgical cyto reduction confers a survival benefit by producing a biologically more homog enous tumor. (C) 2000 Academic Press.