Increased incidence of neoplasia in association with chronic lymphocytic leukaemia.

Etiologic factors were evaluated in an attempt to answer the question: ‘Does chronic lymphocytic leukaemia predispose to other neoplasms?’ The occurrence of the CLL prior to or simultaneous with the second neoplasm in 70% of instances, the known loss of immunologic function, both in the circulating immunoglobulins and in the fixed tissue response in the patient with CLL, and in some instances the use of immunosuppressive drugs and/or radiotherapy as well as prolongation of life, may be the important factors in the increased incidence of second neoplasms demonstrated in patients with chronic lymphocytic leukaemia. A further evaluation of this possible reduced immunity to neoplasms in the patient with CLL is certainly justified.