Application value of splenic hilar lymphadenectomy in patients with Siewert type II and III adenocarcinoma of esophagogastric junction and a tumor diameter .GEQ.4 cm

Abstract

Objective To investigate the long-term outcomes of splenic hilar lymphadenectomy (SPL) in patients with Siewert type Ⅱ and Ⅲ adenocarcinoma of esophagogastric junction (AEG) and a tumor diameter≥4 cm after radical total gastrectomy. Methods The retrospectively cohort study was conducted. The clinico-pathological data of 412 patients with Siewert type Ⅱ and Ⅲ AEG and a tumor diameter≥4 cm who were admitted to the Fujian Medical University Union Hospital from December 2007 to December 2013 were collected. Transabdominal and open or laparoscopic radical total gastrectomies were applied to 412 patients by surgeons in the same team. Of 412 patients, 154 receiving spleen-preserving SPL in situ were allocated into the SPL group and 258 who didn′t receive SPL were allocated into the non-SPL group. Observation indicators included: (1) surgical situations, (2) follow-up situations, (3) postoperative survival factors analysis in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm. Follow-up using outpatient examination, door-to-door visit, correspondence and telephone interview was performed once every 3 months within 2 years postoperatively and once every 6 months within 3-5 years postoperatively up to June 2015. Follow-up included regular physical examination, laboratory examinations (levels of CA19-9, CA72-4 and CEA), chest X-ray, total abdomen color Doppler ultrasonography or computed tomography (CT) scan and annual gastroscopy. The overall survival was from operation to the last follow-up or death or deadline of follow-up database (loss to follow-up and dying of other diseases). Measurement data with normal distribution were represented as ±s and comparison between groups was analyzed using the t test. Measurement data with skewed distribution were described as M (range) and comparison between groups was analyzed using the Mann-Whitney U test. Count data were analyzed using the chi-square test or Fisher exact probability. The survival rate and survival comparison were respectively done by the Kaplan-Meier method and the Log-rank test. The univariate analysis and multivariate analysis were done using the chi-square test and COX regression model. Results (1) Surgical situations: operation time, volume of intraoperative blood loss and number of lymph node dissected were (217±65)minutes, 50 mL (range, 10-1 000 mL), 38±13 in the SPL group and (204±54)minutes, 50 mL (range, 5-2 000 mL), 31±10 in the non-SPL group, respectively, with no statistically significant difference in volume of intraoperative blood loss between the 2 groups (Z=1.495, P>0.05) and with statistically significant differences in operation time and number of lymph node dissected between the 2 groups (t=2.140, 5.400, P 0.05). (2) Follow-up situations: 384 patients were followed up for 48 months (range, 17-89 months). The 3-year overall survival rate and disease-free survival rate were respectively 72.7%, 67.4% in the SPL group and 54.4%, 48.5% in the non-SPL group, with statistically significant differences between the 2 groups (χ2=7.580, 12.380, P 0.05). Among patients with Siewert type Ⅲ AEG, 3-year overall survival rate and disease-free survival rate which were 72.4% and 68.3% in the SPL group were significantly higher than that which were 48.3% and 42.2% in the non-SPL group (χ2=8.990, 14.030, P<0.05). (3) Postoperative survival factors analysis in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm: results of univariate analysis showed that age, American Society of Anesthesiologists (ASA) score, tumor differentiation, splenic hilar dissection, T stage, N stage and TNM stage were factors affecting postoperative 3-year overall survival rate in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm (χ2=8.825, 7.485, 6.766, 8.996, 14.024, 26.002, 19.461, P<0.05). There were correlations among age, splenic hilar dissection, N stage, TNM stage and postoperative 3-year disease-free survival rate in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm (χ2=6.743, 14.038, 26.596, 21.285, P<0.05). Results of multivariate analysis showed that age≥65 years, without splenic hilar dissection, T stage and N stage were independent risk factors affecting postoperative 3-year overall survival rate in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm [HR=1.817, 0.458, 1.613, 1.312, 95% confidence interval (CI): 1.117-2.955, 0.292-0.721, 1.129-2.304, 1.004-1.714, P<0.05]. Age≥65 years, without splenic hilar dissection and TNM stage were independent risk factors affecting postoperative 3-year disease-free survival rate in patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm (HR=1.807, 0.442, 1.799, 95%CI: 1.258-2.596, 0.228-0.679, 1.004-3.224, P<0.05). Conclusions SPL should be performed to patients with Siewert type Ⅲ AEG and a tumor diameter≥4 cm due to higher lymph node metastasis rate, and it will be beneficial to survival of patients. Key words: Esophagogastric junction neoplasms, adenocarcinoma; Siewert classification; Total gastectomy; Splenic hilar lymphadenectomy