"Optimal" cytoreduction for advanced epithelial ovarian cancer: a commentary

To derive the most appropriate threshold to classify primary cytoreductive operations as "optimal" and address the clinical significance of this issue.

Criteria used to classify primary cytoreductive outcomes are reviewed. Survival outcomes are analyzed to address relative influences of the completeness of cytoreduction and "biological aggressiveness", as manifested by the extent of intra-abdominal metastases.

Most cohorts analyzing relative influences of metastatic tumor burden and the dimension of residual disease on survival report completeness of cytoreduction to influence the prognosis more significantly than tumor burden, with necessity to perform various procedures having minimal or no influence. Equivalent survival is reported for completely cytoreduced patients with stage III disease whether substages IIIa/b (smaller tumor burden) are excluded or included. However, some stage IIIc series report more favorable median and 5-year survivals for small fractions of completely cytoreduced patients than series with a large visibly disease-free fraction. Increasing fractions of complete cytoreduction are reported in recent cohorts, without increase in morbidity.

Complete primary cytoreduction improves the prognosis for survival significantly more than a small dimension of residual disease. Although prospective randomized trials addressing surgical issues have not been undertaken and numerous variables may reflect "biological aggressiveness" by influencing the prognosis, available data justify elimination of macroscopic disease to be the most appropriate objective of primary cytoreductive surgery. Stratification of survival by dimensions of residual disease in an investigational setting should include a visibly disease-free subgroup and if used, the term "optimal" should be applied to patients undergoing complete cytoreduction.