[Integration and analysis of associated data in surgical treatment of gastric cancer based on multicenter, high volume databases].

OBJECTIVE: To elucidate the current diagnosis and treatment status of gastric cancer in the Chinese population based on three high volume databases.

METHODS: Clinical and pathological data of patients who underwent gastric cancer resection with complete follow-up information between January 2000 and December 2012 from Sun Yat-sen University Cancer Center, The First Affiliated Hospital of China Medical University and Tianjin Medical University Cancer Hospital were retrospectively analyzed. The overall survival rate was calculated by Kaplan-Meier method. The prognostic risk factors were analyzed by using Cox proportional hazards model.

RESULTS: A total of 8 338 cases were enrolled into the study, including 2 977 cases (35.7%) from Sun Yat-sen University Cancer Center, 3 043 cases (36.5%) from The First Affiliated Hospital of China Medical University and 2 318 cases (27.8%) from Tianjin Medical University Cancer Hospital. There were 5 852 male cases and 2 486 female cases with a ratio of 2.4 to 1.0. The age of patients was from 15 to 89 years old (median 59 years old). The ratio of early gastric cancer (T1NanyM0) was 11.5% (956/8 338). There were 2 226 gastric cancer cases (26.7%) originating from the fundus and cardiac region, 1 637 cases (19.6%) from the body, 3739 (44.9%) cases from the antrum, and 736 cases (8.8%) from the whole stomach. The median maximal tumor diameter was (4.5 ± 2.8) cm. Based on the Lauren classification, 3 448 cases (41.4%) were intestinal type and 4 890 cases (58.6%) diffuse type. A total of 1 975 cases (23.7%) and 6 363 cases (76.3%) underwent complete and subtotal gastrectomy respectively. The majority of patients (7 707 cases, 92.4%) underwent radical gastric resection, while 631 cases (7.6%) palliative resection. According to AJCC/UICC seventh edition of gastric cancer TNM staging system, 802 patients (9.6%) were stage I(A, 735 patients (8.8%) stage I(B, 695 patients (8.3%) stage II(A, 1 507 patients (18.1%) stage II(B, 1 247 patients (15.0%) stage III(A, 1 342 patients (16.1%) stage III(B, 1 583 patients (19.0%) stage III (C and 427 patients (5.1%) stage IIII(. The average number of retrieved lymph node was 21.0 ± 13.1, in which 5 761 patients (69.1%) had more than 15 retrieved lymph nodes. The overall 1-, 3-, 5- and 10-year survival rates were 83.0%, 56.8%, 49.1% and 43.0% respectively. For patients receiving radical resection, the 1-, 3-, 5- and 10-year survival rates were 84.9%, 59.5%, 51.7% and 45.3% respectively. The overall 5-year survival rates for different stages were as follows: stage I(A 93.8%, stage I(B 80.8%, stage II(A 70.8%, stage II(B 59.6%, stage III(A 44.4%, stage III(B 32.9%, stage III(C 18.9% and stage IIII( 10.2%. Cox regression model showed that age, tumor site, tumor size, Lauren type, T staging, N staging, M staging and number of retrieved lymph nodes were independent factors affecting the prognosis of gastric cancer patients (P=0.000).

CONCLUSION: Retrospective study on these domestic three high volume databases demonstrates the clinical and pathological characteristics of gastric cancer based on Chinese population, which is expected to stand as a ground of basic data for future clinical research.