ABSTRACT
<p><b>OBJECTIVE</b>Extraovarian peritoneal serous papillary carcinoma (EPSPC) is both histologically and clinically similar to stage III-IV ovarian papillary serous carcinoma (OPSC). The purpose of this study is to investigate the clinical findings, treatment, and outcome of EPSPC patients compared with stage III-IV OPSC patients.</p><p><b>METHODS</b>The data of 12 EPSPC patients and 45 stage III-IV OPSC patients were retrospectively reviewed, comparing the characteristics on clinical presentation and treatment, sensitivity to first-line chemotherapy agents and survival.</p><p><b>RESULTS</b>By analysis of patients' characteristics, presenting signs and symptoms, type and extent of surgery, tumor response to first-line chemotherapy, recurrence-free interval, recurrence site and serum CA-125 levels, no significant difference was observed between the EPSPC patients and stage III-IV OPSC controls. The prevailing presenting symptoms were abdominal mass and ascites. The mainstay of treatment was debulking surgery followed by adjuvant platinum-based chemotherapy. The complete clinical response of stage III-IV OPSC was 91.8% compared with 25.0% for women with EPSPC (P < 0.01).</p><p><b>CONCLUSION</b>The clinical and surgical characteristics of EPSPC are similar to those of stage III-IV OPSC. When the same treatment strategy is applied, similar response and survival are expected in either condition.</p>