Worldwide esophageal cancer collaboration

The aim of this study is to report assemblage of a large multi-institutional international database of esophageal cancer patients, patient and tumor characteristics, and survival of patients undergoing esophagectomy alone and its correlates. Forty-eight institutions were approached and agreed to participate in a worldwide esophageal cancer collaboration (WECC), and 13 (Asia, 2; Europe, 2; North America, 9) submitted data as of July 1, 2007. These were used to construct a de-identified database of 7884 esophageal cancer patients who underwent esophagectomy. Four thousand six hundred and twenty-seven esophagectomy patients had no induction or adjuvant therapy. Mean age was 62 +/- 11 years, 77% were men, and 33% were Asian. Mean tumor length was 3.3 +/- 2.5 cm, and esophageal location was upper in 4.1%, middle in 27%, and lower in 69%. Histopathologic cell type was adenocarcinoma in 60% and squamous cell in 40%. Histologic grade was G1 in 32%, G2 in 33%, G3 in 35%, and G4 in 0.18%. pT classification was pTis in 7.3%, pT1 in 23%, pT2 in 16%, pT3 in 51%, and pT4 in 3.3%. pN classification was pN0 in 56% and pN1 in 44%. The number of lymph nodes positive for cancer was 1 in 12%, 2 in 8%, 3 in 5%, and >3 in 18%. Resection was R0 in 87%, R1 in 11%, and R2 in 3%. Overall survival was 78, 42, and 31% at 1, 5, and 10 years, respectively. Unlike single-institution studies, in this worldwide collaboration, survival progressively decreases and is distinctively stratified by all variables except region of the world. A worldwide esophageal cancer database has been assembled that overcomes problems of rarity of this cancer. It reveals that survival progressively (monotonically) decreased and was distinctively stratified by all variables except region of the world. Thus, it forms the basis for data-driven esophageal cancer staging. More centers are needed and encouraged to join WECC.