P1.08-071 Surgery for Lung Cancer with Mediastinal Lymph Node Metastasis - Effectiveness of Extended Bilateral Mediastinal Lymphadenectomy

Abstract

The role of surgery in the treatment of non-small-cell lung cancer (NSCLC) with clinically manifested mediastinal node metastasis is controversial even in resectable cases. Hata et al. used scintigraphy in healthy volunteers to show that main lymphatic route from any pulmonary lobe was connected with both sides of supraclavicular lymph nodes through the superior madiastinal nodes. They considered bilateral mediastinal lymphadenectomy contributes the survival of the patient with NSCLC. Due to anatomical limitation, it is difficult to perform complete dissection of superior mediastinal lymph nodes through the left thoracotomy. We had devised extended bilateral mediastinal lymphadenectomy and lung resection through a median sternotomy (ND3 operation) for Left NSCLC, and reported that it can allow for complete dissection of all stations of mediastinal lymph nodes. The aim of this study is to add knowledge on mediastinal lymphadenectomy by evaluating the feasibility and efficiency of our ND3 operation. We retrospectively studied 283 patients who underwent ND3 operation due to Left NSCLC, from January 1988 till December 2015. All operations were performed through the median sternotomy. The lymph nodes around the right and left recurrent laryngeal nerves directly under the thyroid gland, and then a series of lymph nodes on the bilateral sides along the trachea were dissected. Lymph node station #2R, #4R, #2L, #4L, #3a, #5, #6, #7, ( #8, #9:Left lower NSCLC) and part of #1R, #1L were removed. Overall 5-year survival rate in the 283 patients was 61.7%. Operative mortality was 3.1%,(1.1% after 2006) Lymph node metastasis to the mediastinum was confirmed in 91 (32.1%) patients (pN2 was 50,pN3α was 23, pN3β was 2, pN3γ was 16). According to pathological stages, five-year survival rate was 88.4% in stage IA, 74.5% in stage IB, 61.3% in stage IIA, 68.4% in stage IIB, 46.8% in stage IIIA, 40.8% in stage IIB. Five-year survival rate were 47.9% in cN2(n=45), 46.7% in cN3α(n=19),47% in pN2(n=50), and 47.5% in pN3α(n=23). Surgery for Stage III-N2,N3 Lt. NSCLC achieved good long-term survival. Our results suggest that ND3 operation would provide better prognosis in the patients with mediastinal lymph node metastasis, and it does not increase mortality. We can assume that our ND3 operation in Lt. NSCLC with mediastinal lymph node involvement represent feasible, safe, and effective option. It is important to perform curative operation with complete dissection of all station of mediastinal lymph nodes. Surgery should be considered as a first treatment for patients with stage III-N2,N3 Lt.NSCLC.