Comparison of survival outcomes between transthoracic and transabdominal surgical approaches in patients with Siewert-Ⅱ/Ⅲesophagogastric junction adenocarcinoma:a single-institution retrospective cohort study

Objective： To compare the survival outcomes of transabdominal （TA） and transthoracic （TT） surgical approaches in patients with Siewert-II/III esophagogastric junction adenocarcinoma. Methods： This retrospective study was conducted in patients with Siewert-II/III esophagogastric junction adenocarcinoma who underwent either TT or TA operations in the West China Hospital between January 2006 and December 2009. Results： A total of 308 patients （109 in the TT and 199 in the TA groups） were included in this study with a follow-up rate of 87.3%. The median （P25, P75） number of harvested perigastric lymph nodes was 8 （5, 10） in the TT group and 23 （16, 34） in the TA group （P〈0.001）, and the number of positive perigastric lymph nodes was 2 （0, 5） in the TT group and 3 （1, 8） in the TA group （P〈0.004）. The 5-year overall survival （OS） rate was 36% in the TT group and 51% in the TA group （P=0.005）. Subgroup analysis by Siewert classification showed that 5-year OS rates for patients with Siewert II tumors were 38% and 48% in TT and TA groups, respectively （P=0.134）, whereas the 5-year OS rate for patients with Siewert III tumors was significantly lower in the TT group than that in the TA group （33% vs. 53%; P=0.010）. Multivariate analysis indicated that N2 and N3 stages, RI/R2 resection and a TT surgical approach were prognostic factors for poor OS. Conclusions： Improved perigastric lymph node dissection may be the main reason for better survival outcomes observed with a TA gastrectomy approach than with TT gastrectomy for Siewert III tumor patients.

Significance and prognostic value of lysosomal enzyme activities measured in surgically operated adenocarcinomas of the gastroesophageal junction and squamous cell carcinomas of the lower third of esophagus

AIM： To establish whether there are fundamental differences in the biochemistries of adenocarcinomas of the gastroesophageal junction （GEJ） and the squamous cell carcinomas of the lower third of the esophagus （LTE）. METHODS： Between February 1, 1997 and February 1, 2000, we obtained tissue samples at the moment of resection from 54 patients for biochemical analysis. The full set of data could be comprehensively analyzed in 47 of 54 patients＇ samples （81%）. Of these, 29 were adenocarcinomas of the GEJ Siewert type Ⅰ （n = 8）, type Ⅱ （n = 12）, type Ⅲ （n = 9）, and 18 presented as squamous cell carcinomas of the LTE. We evaluated the mean values of 11-lysosomal enzyme and 1-cytosol protease activities of the tumorous and surrounding mucosae as well as their relative activities, measured as the ratio of activity in tumor and normal tissues from the same patient. These data were further analyzed to establish the correlation with tumor localization, TNM stage （lymph-node involvement）, histological type （papillary, signet-ring cell, tubular）, state of differentiation （good, moderate, poor）, and survival （≤24 or ≥24 mo）. RESULTS： In adenocarcinomas, the activity of α-mannosidase （AMAN）, cathepsin B （CB） and dipeptidyl-peptidase Ⅰ （DPP Ⅰ） increased significantly as compared to the normal gastric mucosa. In squamous cell carcinomas of the esophagus, we also found a significant difference in the activity of cathepsin L and tripeptidyl-peptidase Ⅰ in addition to these three. There was a statistical correlation of AMAN, CB, and DPP Ⅰ activity between the level of differentiation of adenocarcinomas of the GEJ and lymph node involvement,because tumors with no lymph node metastases histologically confirmed as well-differentiated, showed a significantly lower activity. The differences in CB and DPP Ⅰ activity correlated well with the differences in survival rates, since the CB and DPP Ⅰ values of those who died within 24 mo following surgical intervention were significantly higher than of those who survived for 2 years or more. CONCLUSION： Adenocarcinomas of the GEJ form a homogenous group from a tumor-biochemical aspect, and differ from the biochemical characteristics of squamous cell carcinomas of the LTE on many points. When adenocarcinomas of the GEJs are examined at the preoperative phase, the ratio of the performed AMAN, CB, and DPP Ⅰ enzymatic activity of the tissue sample from the tumor and adjacent intact mucosa within 2 cm of the tumor may have a prognostic value even in the preoperative examination period, and may indicate that ranking of these patients into the neo-adjuvant treatment group should be considered.