RISK OF CANCER FOLLOWING SPLENECTOMY

Only 2 small population-based studies have previously evaluated cancer risk in splenectomized patients. Our objective was thus to investigat e cancer incidence following splenectomy for external trauma or for su rgical treatment of non-malignant conditions of adjacent organs. Using the unique personal identification number assigned to each Swedish re sident, we linked centralized hospitalization records with nationwide total population and cancer incidence data. We excluded cancers diagno sed within the first 12 months after splenectomy and computed standard ized incidence ratios for 1,295 patients (contributing 14,390 person-y ears) splenectomized for external trauma and for 985 patients (contrib uting 8,911 person-years) whose splenectomy accompanied surgical treat ment of nonmalignant conditions of adjacent organs (mostly peptic ulce rs), using age-, sex- and period-specific rates for cancer incidence d erived from the entire Swedish population. Patients undergoing splenec tomy for external trauma had no significant excess of total or site-sp ecific cancers. Individuals splenectomized in conjunction with surgery for non-malignant conditions of adjacent organs had a non-significant 40% elevated risk of total cancer, with significant increases of lung and ovarian cancers. The excesses of lung and ovarian cancers may be due to chance, but we could not exclude the conditions for which the s urgery was performed, other treatments or common predisposing factors (such as cigarette smoking, which has been linked with both peptic ulc er and lung cancer). (C) 1996 Wiley-Liss, Inc.