The development of a second hematologic malignancy among patients with chronic lymphocytic leukemia (CLL) appears to be uncommon — potentially affecting 4% of patients — according to the results of a nationwide cancer registry study recently published in the European Journal of Haematology.
The study researchers retrospectively identified 2631 patients with CLL who were registered between 2003 and 2012 in the Cancer Registry of Norway. Patients were followed for a median of 6.6 years, and during that follow-up period, 103 of 2631 patients (4%) had a confirmed second hematologic malignancy. The most common was diffuse large B-cell lymphoma (DLBCL; 65 patients) followed by myeloid neoplasia (15 patients) and Hodgkin lymphoma (12 patients).
Patients who developed a second hematologic malignancy tended to be younger (median age 66 vs 72 years; P <.001) and male (68% vs 57%; P =.03) compared with patients who did not.
A survival analysis showed that those who did not develop a second hematologic malignancy lived a median of 7 years longer than patients who did (9.3 vs 2.3 years; P <.001). Broken down by type, patients who developed Hodgkin lymphoma had the worst survival (0.8 years; 95% CI, 0.6-2.9), patients who developed DLBCL lived longer (1.7 years; 95% CI, 0.3-2.6), and patients with myeloid neoplasia lived the longest (2.8 years; 95% CI, 0.4-5.3).
Also, among patients who developed a second hematologic malignancy, those who received CLL treatment before being diagnosed with a second hematologic malignancy had worse survival than those who were treatment-naive (0.8 vs 6.4 years; HR, 2.76; 95% CI, 1.4-5.5, P =.003).
The study authors described the incidence of second hematologic malignancies as a “rare event” in patients with CLL.
Lenartova A, Johannesen TB, Tjønnfjord GE. Chronic lymphocytic leukemia and secondary hematological malignancies: A nation-wide cancer registry study [published online February 14, 2020]. Eur J Haematol. doi: 10.1111/ejh.13396