Long-term outcomes
Fifteen studies conducted multivariate cox regression analysis of OS and were eligible for our analysis (10, 14-25, 32, 33). Pooled analysis of all studies showed superiority of OS in women who had sysLA was close to significance, compared to control group (HR 0.93, 95% CI 0.86 - 1.00). Subgroup analysis of 3 RCTs did not show significant difference in OS between both groups (HR 1.01, 95% CI 0.94 - 1.08) (Figure 3). Due to heterogeneity of study population, a matrix subgroup analysis was conducted using 3 parameters: disease stage, timing of chemotherapy in relation to surgery, and control group (Figure 4). Stagewise, sysLA did not improve survival when performed in early stages (HR 1.04, 95% CI 0.84 - 1.29) (Figure 4: A0). Superiority of sysLA was close to significance in advanced stages (Figure 4: D-F0) and was statistically significant in stage IIB-IV (HR 0.91, 95% CI 0.84 - 0.99, 12 studies) (Figure 4: C0). SysLA did not improve survival in women who received neoadjuvant chemotherapy (HR 0.97, 95% CI 0.73 - 1.29, 4 studies) (Figure 4: T6) regardless of control group (Figure 4: T4-5). In contrast, sysLA significantly improved OS in women treated with adjuvant chemotherapy following surgery (HR 0.91, 95% CI 0.84 - 0.99, 11 studies) (Figure 4: T3). Among women who received adjuvant chemotherapy, sysLA was significantly associated with improved OS in stage IIB to IV (HR 0.90, 95% CI 0.82, 0.98, 8 studies) and III to IV (HR 0.85, 95% CI 0.73 - 0.99, 6 studies) (Figure 4: C3 and D3, respectively). OS benefit of sysLA was most significant in patients with stage III to IV when compared to noLND (HR 0.86, 95% CI 0.77 - 0.96, 3 studies) (Figure 4: D2). Analysis of studies including either optimal debulking only or optimal and suboptimal debulking yielded similar results (HR 0.88, 95% CI 0.76 - 1.01, HR 0.91, 95% CI 0.84 - 1.00). PFS was reported in 8 studies. SysLA was associated with improved PFS compared to control group (HR 0.88, 95% CI 0.79 - 0.99). Subgroup analysis of RCTs (2 studies) was consistent with total analysis (HR 0.88, 95% CI 0.81 - 0.96) (Figure 5).