Chinese Medical Journal 2014;127 (3)
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Original article Evaluation of para-aortic nodal dissection for locoregionally advanced gastric cancer with 1–3 involved para-aortic nodes Zhang Changhua, He Yulong, Roderich E. Schwarz, David D. Smith, Wang Liang, Liu Fakeng and Zhan Wenhua Keywords: gastric cancer; lymphadenectomy; para-aortic node; prognosis Background Prophylactic para-aortic nodal dissection (PAND) has no proven benefits for potentially curable advanced gastric cancer. However, the value of therapeutic PAND for involved para-aortic nodes (PANs) in patients with locally advanced gastric cancers has not been determined yet. Methods Between 1998 and 2010, 157 gastric cancer patients with 1–3 involved PANs underwent extended D2 (D2+) lymphadenectomy plus PAND (PAND group, n=69) or extended D2 lymphadenectomy alone (non-PAND group, n=88). The clinicopathologic features and prognostic data were compared between the two groups. A propensity score-adjusted analysis was used for a balanced comparison. Results The rate of PAN metastasis was 40.6% (28/69) in the PAND group. The 5-year survival rate was significantly higher in the PAND group than in the non-PAND group (43.7% vs. 31.8%, P=0.044). Compared to the non-PAND group, the death hazard ratios in the PAND group were 0.45 (95% CI 0.274−0.739; P=0.002) and 0.536 (95% CI 0.328−0.861; P=0.0097) by multivariate analysis without and with propensity score adjustment respectively. Recurrence rate at 5 years was 39.1% in the PAND group and 43.2% in the non-PAND group (P=0.628). Conclusion Extended D2 lymphadenectomy plus PAND is associated with superior outcomes for advanced gastric cancer patients with 1–3 involved PANs. Chin Med J 2014;127 (3): 435-441
G
astric cancer is the second leading cause of cancerrelated death throughout the world, with half of the world total case number occurring in Eastern Asia, mainly in China.1-5 Radical gastrectomy with D2 lymphadenectomy has been the standard treatment for patients with curable gastric cancer in Eastern Asia and has been advocated in the Western countries too.2,3,6-9 Chemotherapy helps prolong survival in cases of advanced disease,10,11 but surgical resection is the most effective treatment for curable gastric cancer.1,6,7 Once the gastric tumor invades the subserosa (Stage T3), the serosa (Stage T4a), or the adjacent structures (Stage T4b), the rate of metastases to para-aortic lymph nodes (PANs) increase to between 10% and 30%.12-14 Roviello et al12 reported that 12.9% patients (47/286) with PANs involvement resulted in 5-year survival rate of approximately 17% after para-aortic nodal dissection (PAND). In the Japanese (JCOG) 9501 trial,15 D2 plus PAND was compared to D2 lymphadenectomy alone for tumor category T2b to T4 potentially curable gastric cancer. Results showed that PAND did not mediate any additional survival benefits, but the trial was criticized for the exclusion of macroscopic PAN metastases and its resulting “prophylactic” PAND evaluation.16,17 The value of therapeutic PAND in curative-intent dissection of pathologically positive PANs is undetermined yet.15-18 Since the early 1990s, D2 lymphadenectomy has been performed for advanced gastric cancer in the First Affiliated Hospital of Sun Yat-sen University. Extended D2 lymphadenectomy has been performed for T3 or T4 gastric cancer with involved perigastric nodes, and PAND has been added to this strategy in some cases with 1–3
involved PANs. A prospective gastric cancer database was created from 1994. The goal of this study was to evaluate the efficacy of therapeutic PAND for gastric cancer with limited PANs involvement. In this study, extended D2 lymphadenectomy plus PAND was retrospectively compared to extended D2 lymphadenectomy alone for locally advanced gastric cancer with 1–3 involved PANs to determine the benefit of PAND and propensity score adjusted analysis was performed to account for biases associated with the treatment selection. METHODS Inclusion and exclusion criteria The inclusion criteria for this study were as follows: (1) DOI: 10.3760/cma.j.issn.0366-6999.20130664 Department of Gastrointestinopancreatic Surgery, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China (Zhang CH, He YL, Wang L, Liu FK and Zhan WH) Gastric Cancer Center of Sun Yat-sen University, Guangzhou, Guangdong 510080, China (Zhang CH, He YL, Wang L, Liu FK and Zhan WH) Department of Surgery, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA (Schwarz RE) Division of Biostatistics, City of Hope National Medical Center, Duarte, CA 91010, USA (Smith DD) Correspondence to: Dr. He Yulong, Department of Gastrointestinopancreatic Surgery, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong 510080, China (Tel: 86-2087755766 ext. 8211. Fax: 86-20-87331059. Email: ylh@medmail. com.cn) This study was supported by the National Natural Science Foundation of China (No. 30700805 and No. 81272643) and the Young Teacher Training Project of Sun Yat-sen University (No. 09ykpy49).
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histologically proven advanced gastric cancer, radical gastrectomy with D2 (D2+) lymph-node dissection; (2) patients aged between 20 and 70 years; (3) 1–3 involved PANs diagnosed by preoperative CT and intraoperative exploration; (4) pT3 or pT4 tumor based on postoperative pathology; (5) no synchronous or metachronous cancers or remnant gastric cancer; and (6) no peritoneal, distant metastasis, ascites, or cancer cells in peritoneal cytology. Four exclusion criteria were employed: (1) age >70 years or