Chang 2012b.

Study characteristics
Methods	Retrospective review of medical records
Participants	Consecutive women with stage IIIC primary epithelial ovarian, fallopian tube or peritoneal cancer who underwent primary cytoreductive surgery at Ajou University Hospital between 1 January 2000 and 31 December 2011 After primary surgery, all women received adjuvant chemotherapy consisting of cisplatin (75 mg/m2) or carboplatin (area under the curve; 5 to 7) and paclitaxel (135 mg/m2) based systemic combination chemotherapy (every 3 weeks for 6 to 9 cycles) Exclusion: primary cytoreduction at an outside institution, neoadjuvant chemotherapy, stage IIIC disease based on lymph node metastasis only or borderline malignancy N = 191 Median age was 54 years (range 30 to 78) Median BMI 23.2 (18.1 to 35.2) ASA 1 or 2: 107 (56.6%), 3 or 4: 74 (39.2%) Median pre‐op CA‐125 173.1 (range 4.5 to 21,677) Histological subtypes: serous: 155 (82%), mucinous: 4 (2.1%), endometrioid: 4 (2.1%), clear cell: 9 (4.8%), mixed: 17 (9.0%) Grade 1: 26 (13.8%), grade 2: 67 (35.4%), grade3: 5 (2.6%) Ascites < 1000 mL (57.7%), > 1000 mL (42.3%) Peritoneal carcinomatosis: yes:139 (73.5%), no: 50 (26.5%) Systematic lymphadenectomy (n = 135), no lymphadenectomy (n = 54) Lymphadenectomy; pelvic only (22.2%), pelvic and para‐aortic (77.8%)
Residual disease details	Residual disease were defined: NMRD: 61 (32.3%) SVRD (0.1 to 1.0 cm): 67 (35.4%) LVRD (> 1.0 cm): 61 (32.3%) Overall surgical morbidity ‐ blood transfusion, deep vein thrombosis, sepsis, intestinal obstruction, ileus, lymphocyst or wound dehiscence was significantly higher in women who had lymphadenectomy
Outcomes	Multivariate analysis for OS: SVRD 0.1 cm to 1 cm vs NMRD: HR 2.25 (95% CI 1.25 to 4.03) LVRD > 1 cm vs NMRD: HR 3.09 (95% CI 1.80 to 5.30) HRs adjusted for age, performance of radical surgery and performance of lymphadenectomy
Risk of bias (QUIPS)	1. Study participation (a‐f): low risk Adequate number of participants and description of target population. Baseline characteristics, eligibility criteria, sampling frame and period/place study took place presented clearly. 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): low risk Valid and reliable 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 HR for OS was adjusted for residual disease, type of surgery, performance of lymphadenectomy and age in a multivariable Cox model 6. Statistical analysis and reporting (a‐d): high risk No conceptual framework; unclear of variable selection criteria in multivariate model Outcome: progression‐free survival 4. Outcome measurement (a‐c): low risk Definition of PFS not provided but it usually has a standard definition. 5. Adjustment for other prognostic factors (a‐g): low risk HR for PFS was adjusted for residual disease, type of surgery, performance of lymphadenectomy and age in a multivariable Cox model 6. Statistical analysis and reporting (a‐d): high risk No conceptual framework; unclear of variable selection criteria in multivariate model
Notes	Systematic lymphadenectomy was performed in 135 (71.4%) of whom 105 had both pelvic and para‐aortic lymphadenectomy. The mean number of dissected pelvic and para‐aortic nodes were 25 (range 11 to 57) and 11 (range 3 to 35), respectively. 53.4% were found to have grossly enlarged lymph nodes during surgery. Of 135 women who underwent systematic lymphadenectomy, positive lymph nodes were found in 59%. The median unadjusted OS; lymphadenectomy 66 months, no lymphadenectomy 40 months. Subgroup analysis of NMRD: median OS 86 month versus no lymphadenectomy 46 months Of 189 women, tumour recurred in 110 women (58.2%) and 90 (47.6%) died of disease. 65 women with lymphadenectomy and 45 without lymphadenectomy had disease recurrence and there is no significant difference in the site of disease recurrence.