Topic: D. Clinical Cancer
The Number of Lymph Nodes Removed Predicts Survival in Esophageal Cancer: an International Study of the Impact of Extent of Surgical Resection
Christian G Peyre1, Tom R DeMeester1, Nasser K Altorki2, Ermanno Ancona3, Selwyn M Griffin4, Arnulf H Hoelscher5, Toni Lerut6, Thomas W Rice7, J J Van Lanschot8, John Wong9
1University of Southern California, Los Angeles, CA;2Weill Medical College of Cornell University, New York, NY;3University of Padova School of Medicine, Padua, Italy4Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom5University of Cologne, Cologne, Germany6University Hospitals Leuven, Leuven, Belgium7Cleveland Clinic, Cleveland, OH;8Erasmus University, Rotterdam, The Netherlands9University of Hong Kong, Hong Kong, China
SEER data indicates that number of lymph nodes removed impacts survival in gastric cancer. Our aim was to study this relationship in esophageal cancer.
The study population included 2166 esophageal cancer patients (1273 adenocarcinoma, 893 squamous) from nine international centers that had R0 esophagectomy prior to 2002 and were followed at least 5 years or until death. Patients treated with neoadjuvant or adjuvant therapy were excluded.
Operations consisted of esophagectomy with (1619) and without (547) thoracotomy. Median number of nodes removed was 17 (IQR10-28). There were 448 patients with stage I, 805 stage II, and 913 stage III. Absolute 5-year survival was 37%. Logistic regression analysis showed higher T status, N status, number of involved nodes and squamous cell type decreased survival. The number of lymph nodes removed was an independent predictor of increased survival (p<0.0001). The optimal threshold by ROC analysis for this survival benefit was removal of 28 nodes adjusted for T and N status, number of positive nodes and cell type. The benefit of removing at least 28 lymph nodes, while evident in early stage disease, was most pronounced in patients with advanced tumors. Absolute improvement in survival for Stage I (T1N0) patients was 11% (83% vs. 72%, p=0.0069). Patients with T3N1disease had an absolute survival benefit of 15% (26% vs. 11%, p<0.0001).
The number of lymph nodes removed is an independent predictor of survival after esophagectomy for cancer. To maximize this survival benefit at least 28 regional lymph nodes must be removed.