Background. Primary, secondary, and possibly tertiary surgical cytoreduction in patients with recurrent epithelial ovarian (EOC), fallopian tube (FTC), or primary peritoneal (PPC) cancer appears to be associated with a Survival benefit. The objective of this Study was to assess if cytoreduction of recurrences after tertiary cytoreduction offers any potential benefit in these patients. Methods. We performed a retrospective chart review of all patients with recurrent EOC, FTC, OF PPC who underwent additional cytoreductive procedures after a prior tertiary cytoreduction (quaternary cytoreduction) at our institution between 1991 and 2008. Disease-specific survival (DSS) was calculated from the time of quaternary cytoreduction to last follow-Lip. Univariate analyses were used to analyze Outcomes and to identify potential prognostic factors. Results. A total of 15 patients were identified, of which 7 (47%) have died of disease. All patients had undergone prior optimal secondary and tertiary Surgical cytoreductive procedures. The size of residual disease varied from 0 (in 10 cases/67%) to; 1 cm (in 2 cases, 13%). Residual disease (<= 1 cm vs > 1 cm) and number of recurrence sites (single vs multiple) were found to be significant prognostic factors on Univariate analysis. Conclusions. Cytoreductive Surgery beyond tertiary cytoreduction may be a reasonable option in highly select patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer. especially in the setting of a single site of recurrent disease. (C) 2009 Elsevier Inc. All rights reserved.