Survival impact of number of removed para-aortic lymph nodes in stage I epithelial ovarian cancer

Purpose The survival effect of presence or absence of lymphadenectomy in early-stage epithelial ovarian cancer (EOC) was priorly shown but the effect of number of removed lymph nodes kept in background. We aimed to evaluate the survival impact of number of removed lymph nodes and their localizations in stage I EOC. Methods This study included 182 patients. The best cut-off levels for number of pelvic and para-aortic lymph nodes (PaLN) were 24 and 10, respectively. Univariate and multivariate survival analyses were performed for these cut-offs and other prognostic factors. Results The median age of the patients was 49. The median number of removed pelvic and paraartic lymph nodes were 29 and 9, respectively. The median overall (OS) and progression-free survival (PFS) were 67 and 50 months, respectively. The 5-year OS rate was 89.6%. Recurrence occured in 24 (19.5%) patients. In univariate analyses tumor grade (p: 0.005), pelvic LN number (p: 0.041) and PaLN number (p: 0.004) were the factors that were significantly associated with PFS. Tumor grade and PaLN number were independently and significantly associated with PFS in multivariate analyses (p: 0.015 and p: 0.017, respectively). In OS analyses, age, tumor grade, presence of LVI, number of pelvic and PaLNs were the significantly associated factors (p < 0.05 for all). In multivariate analyses, age and PaLN number were independently and significantly associated with OS (p: 0.011 and p: 0.021, respectively). Conclusions The number and localizations of removed lymph nodes may have a survival affect in stage I EOC. We also think that this study may constitute a kernel point for larger prospective series on lymph node number and lymphatic regions.