Prognostic significance of the number of pelvic lymph-nodes resection in patients with cervical adenocarcinoma: An analysis from JGOG 1070S study.

Abstract

5529 Background: Although resection of more than 20 lymph-nodes is considered to be adequate in pelvic lymphadenectomy for cervical cancer patients, prognostic significance of the number of resected lymph-nodes (PLN-num) is clinically still unknown. Methods: This nationwide multicenter retrospective study (JGOG 1070S) examined consecutive 693 patients with clinical stage IB-IIB cervical cancer who underwent radical hysterectomy including pelvic and/or para-aortic lymphadenectomy between 2008-2009 at 87 institutions of the Japanese Gynecologic Oncology Group. Maximum number of enrollments from one institution was limited 10 or less to minimize the inter-institutional bias. Correlation between PLN-num and prognosis was analyzed using Cox hazard model with considering histological subtypes. Results: Of 473 eligible cases in this study, the average PLN-num per a case in each institution was positively correlated with the number of total cases treated in each institution per year. (R = 0.42, P = 0.012). Patients with high PLN-num showed favorable progression free survival (PFS) (P = 0.12). Focusing on adeno and adeno-squamous carcinomas, significantly improved PFS was shown in high PLN-num cases (P = 0.012), although no significance was found in squamous cell carcinoma (P = 0.754). Multivariate analysis in adeno and adeno-squamous cases showed PLN-num as an independent prognostic factor (HR; 0.46, 95%CI; 0.24–0.84, P = 0.026) along with disease stage and adjuvant therapeutics. Subset analysis of adeno and adeno-squamous cases without adjuvant therapeutics showed significant improvement of survival in high PLN-num group (P = 0.019). Conclusions: In our study, PLN-num in lymphadenectomy for patients with cervical adeno or adeno-squamous carcinoma was clarified to be a significant prognostic factor. Systematic total lymphadenectomy is recommended for these patients to obtain a favorable prognosis.