Demographics of spleen registry populations.

Demographics of the patients with available blood test for IgM memory B cells (A) and those without an available result (B). The gender distribution (male), frequency of malignancy and death, and frequency of early registration (<1month post operation) were compared by Chi squared test. The age at registration was compared by Wilcoxon test and is shown as median and interquartile range (IQR). NS = not significant, NA = not applicable.