No Association of Blood Type O With Neuroendocrine Tumors in Multiple Endocrine Neoplasia Type 1.

ABSTRACT

CONTEXT An association between ABO blood type and the development of cancer, in particular, pancreatic cancer, has been reported in the literature. An association between blood type O and neuroendocrine tumors in multiple endocrine neoplasia type 1 (MEN1) patients was recently suggested. Therefore, blood type O was proposed as an additional factor to personalize screening criteria for neuroendocrine tumors in MEN1 patients. OBJECTIVE: The aim of this study was to assess the association between blood type O and the occurrence of neuroendocrine tumors in the national Dutch MEN1 cohort. DESIGN: This is a cohort study using the Dutch National MEN1 database, which includes more than 90% of the Dutch MEN1 population. Demographic and clinical data were analyzed by blood type. Chi-square tests and Fisher exact tests were used to determine the association between blood type O and occurrence of neuroendocrine tumors. A cumulative incidence analysis (Gray's test) was performed to assess the equality of cumulative incidence of neuroendocrine tumors in blood type groups, taking death into account as a competing risk. RESULTS: The ABO blood type of 200 of 322 MEN1 patients was known. Demographic and clinical characteristics were similar among blood type O and non-O type cohorts. The occurrence of neuroendocrine tumors of the lung, thymus, pancreas, and gastrointestinal tract was equally distributed across the blood type O and non-O type cohorts (Grays's test for equality; P = 0.72). Furthermore, we found no association between blood type O and the occurrence of metastatic disease or survival. CONCLUSIONS: An association between blood type O and the occurrence of neuroendocrine tumors in MEN1 patients was not confirmed. For this reason, the addition of the blood type to screening and surveillance practice seems not to be of additional value for identifying MEN1 patients at risk for the development of neuroendocrine tumors, metastatic disease, or a shortened survival.