Hodgkin lymphoma related to chronic lymphocytic leukemia (Richter syndrome)

This study examined chronic lymphocytic leukemia that develops into Hodgkin lymphoma (Richter syndrome). The study concluded that chronic lymphocytic leukemia-related Hodgkin lymphoma can be treated with ABVD chemotherapy. 

Chronic lymphocytic leukemia (CLL) is a type of cancer that affects white blood cells and bone marrow. CLL causes an increase in white blood cells that prevent healthy blood cells from being produced. CLL mainly affects older people. In some cases of CLL, Richter syndrome can occur.

Richter syndrome is the development of an aggressive lymphoma in patients with CLL. One variant of Richter syndrome is the development of Richter-related Hodgkin lymphoma (HL-RS). Previous studies have shown that between 0.4 and 0.7% of CLL patients will develop HL-RS. Because CLL-related HL-RS is so rare, little is known about the treatment approach for these patients. 

This study aimed to improve the knowledge of CLL-related HL-RS. The medical records of 4,680 patients with CLL were reviewed. 33 out of the 4,680 (0.7%) CLL patients developed HL-RS. The average age at CLL diagnosis was 61 years old. The average age at HL-RS diagnosis was 70 years old.

The average time between CLL diagnosis and HL-RS diagnosis for treated patients was 90 months. For patients who had not been treated for CLL, the average time from CLL diagnosis to HL-RS diagnosis was 13 months. For patents who had been treated with alkylating agents (darcarbazine) for their CLL, the average time from CLL diagnosis to HL-RS diagnosis was 90 months. For patients who were treated with fludarabine-based treatment (FAMP), the average time from CLL diagnosis to HL-RS diagnosis was 97 months.

The average survival time for patients was 37.8 months after HL-RS diagnosis. 79% of patients had advanced disease and 70% were experiencing B symptoms (fever, night sweats, and weight loss) at time of diagnosis. 39% had evidence of disease in lymph nodes in other parts of the body. 50% were considered high-risk based on a prognostic score.

ABVD chemotherapy was used to treat HL-RS in 66.6% of patients. The complete response rate (absence of all detectable cancer after completing treatment) was 68%. Patients who were lower-risk were more likely to achieve complete response. Patients who were diagnosed with late onset HL-RS (more than 12 months after receiving last CLL treatment) were more likely to achieve a complete response. The achievement of a complete response predicted survival.

This study concluded that ABVD is an effective treatment for patients with Hodgkin lymphoma relating to CLL, and is especially effective in patients with late onset HL and lower risk.