Time trends and disparities in lymphadenectomy for gastrointestinal cancer in the United States: a population-based analysis of 326,243 patients.

BACKGROUND

The value of lymphadenectomy in most localized gastrointestinal (GI) malignancies is well established. Our objectives were to evaluate the time trends of lymphadenectomy in GI cancer and identify factors associated with inadequate lymphadenectomy in a large population-based sample.

METHODS

Using the National Cancer Institute's Surveillance Epidemiology and End Results Database (1998-2009), a total of 326,243 patients with surgically treated GI malignancy (esophagus, 13,165; stomach, 18,858; small bowel, 7,666; colon, 232,345; rectum, 42,338; pancreas, 12,141) were identified. Adequate lymphadenectomy was defined based on the National Cancer Center Network's recommendations as more than 15 esophagus, 15 stomach, 12 small bowel, 12 colon, 12 rectum, and 15 pancreas. The median number of lymph nodes removed and the prevalence of adequate and/or no lymphadenectomy for each cancer type were assessed and trended over the ten study years. Multivariate logistic regression was employed to identify factors predicting adequate lymphadenectomy.

RESULTS

The median number of excised nodes improved over the decade of study in all types of cancer: esophagus, from 7 to 13; stomach, 8-12; small bowel, 2-7; colon, 9-16; rectum, 8-13; and pancreas, 7-13. Furthermore, the percentage of patients with an adequate lymphadenectomy (49 % for all types) steadily increased, and those with zero nodes removed (6 % for all types) steadily decreased in all types of cancer, although both remained far from ideal. By 2009, the percentages of patients with adequate lymphadenectomy were 43 % for esophagus, 42 % for stomach, 35 % for small intestine, 77 % for colon, 61 % for rectum, and 42 % for pancreas. Men, patients >65 years old, or those undergoing surgical therapy earlier in the study period and living in areas with high poverty rates were significantly less likely to receive adequate lymphadenectomy (all p < 0.0001).

CONCLUSIONS

Lymph node retrieval during surgery for GI cancer remains inadequate in a large proportion of patients in the USA, although the median number of resected nodes increased over the last 10 years. Gender and socioeconomic disparities in receiving adequate lymphadenectomy were observed.