Second malignant neoplasms in patients with non hodgkin's lymphoma

A retrospective review of the records of 3886 patients with non‐Hodgkin's lymphoma registered at the Princess Margaret Hospital between 1970 and 1985 was undertaken to determine the incidence of second malignant tumours. Three thousand and twenty‐one patients with a minimum documented follow‐up of 6 months from referral were identified for analysis. The overall observed/expected ratio for all cancers in patients with malignant lymphoma was 1, suggesting no increased risk of developing a second malignant neoplasm compared to the general population. When the data were analyzed independently for each tumour site, statistically significant increased risk of developing acute non lymphocytic leukemia (ANLL) (p < 0·001) and carcinoma of the tongue (p < 0·05) were found. An increased risk of lung cancer following lymphoma was detected but was not statistically significant. Survival following diagnosis of ANLL and lung cancer was similar and significantly shorter than that following the diagnosis of other second malignancies. The risk of developing a second primary cancer was significantly related to increasing patient age.