Peiretti 2012.

Study characteristics
Methods	Retrospective medical chart review
Participants	238 consecutive women who underwent rectosigmoid colectomy as part of cytoreductive surgery for ovarian cancer during the study interval were included Median age was 59.7 years (range: 22 to 85 years) FIGO stage IIC: 3 (1%); IIIA: 1(0.4%); IIIB: 2 (0.8%); IIIC: 174 (73%); IV: 58 (24%) Primary site disease: Ovary: 230 (96%) Fallopian tube: 4 (2%) Peritoneal cancer: 4(2%) Tumour grade: 1 to 2: 51 (22%) 3: 184 (77%) N/A: 3 (1%) Histological subtype: Serous: 200 (84%) Endometrioid: 15 (6%) Clear cell: 5 (3%) Mixed: 18 (7%) Median ascites (range): 1500 cm3 100 to 11,000) Italy (157) and USA (81)
Residual disease details	All operations were performed by gynaecologic oncologists Postoperative platinum‐based chemotherapy was administered in all women 62% underwent carbo‐platinum and Taxol regimen Doxorubicin liposomal, gemcitabine and topotecan were the other chemotherapeutic drugs used in association with platinum Complete cytoreduction was defined as no visible residual tumour at the completion of the primary operation. Reported categories for residual disease (mm) where as follows ‐ no. of women (%): NMRD: 99 (41%) SVRD (1 mm to 10 mm): 106 (44%) LVRD (> 10 mm): 32 (15%)
Outcomes	The risk factor significantly associated with decreased overall survival (OS) was the presence of any macroscopic residual disease at the end of surgery (P = 0.003) The median overall survival time from the time of surgery for all women was 55 months A statistically significant difference (P = 0.002) was observed in OS between the group with no macroscopic residual disease (median of 72 months) and the other women with any other gross residual disease (median of 42 months) Median estimated blood loss (range): 1000 cm3 (200 to 8500) Intraoperative blood transfusion: 152 (64%) Postoperative blood transfusion: 150 (63%) Median length of hospitalisation (days): 10 (range: 4 to 24 days)
Risk of bias (QUIPS)	1. Study participation (a‐f): low risk Adequate target population. Baseline characteristics, eligibility criteria, sampling frame and period/place study took place presented clearly. Sample consists of small subset (n = 3, 1%) of stage IIC participants. 2. Study attrition (a‐e): unclear risk Unclear if patients with incomplete follow‐up were excluded before arriving at the stated sample size. Insufficient information to permit judgement. 3. Prognostic factor measurement (a‐f): unclear risk Valid and reliable measurement of RD. Multicentre design may introduce heterogeneity in measurement of RD Outcome level assessment: Outcome: overall survival 4. Outcome measurement (a‐c): low risk Definition of OS not provided but it usually has a standard definition 5. Adjustment for other prognostic factors (a‐g): low risk Multivariate model predicting OS adjusted for age, stage, histology, grade and presence of ascites 6. Statistical analysis and reporting (a‐d): high risk No conceptual framework; variable selection criteria for multivariate analysis unstated Outcome: progression‐free survival Not reported
Notes	Mean or median length of follow‐up were not reported Among all groups of women 85% were able to complete at least 5 cycles of (platinum‐based) systematic chemotherapy 50% of women recurred during the study period. Among them, 74% had a recurrence in the upper abdomen. 8% of the women presented with abdominal recurrence associated to pelvic disease. Only 5% of the women showed a relapse in the pelvis 14% of the women presented with distant metastases at the time of recurrence Both univariate and multivariate analyses including the following variables were performed: age, stage, histology, grade, presence of ascites and residual tumour at end of surgery, however no HR are presented in the study