Familial Chronic Lymphocytic Leukemia(CLL): The Mayo Clinic Experience.

Background: Over the last decade, increasing numbers of families with at least 2 cases of CLL or other B-cell lymphoproliferative disorders have been described.

Methods: Families seen at Mayo Clinic with at least one individual diagnosed with CLL and one or more first or second degree relative diagnosed with CLL or a B-cell lymphoproliferative disorder(LPD) were identified. Clinical characteristics and risk stratification test results (cytogenetic abnormalities by FISH, level of CD38 expression, and IgV_H gene mutation status) were extracted and reviewed. Serum, intracellular and CLL B cell secreted levels of pro- and anti-angiogenic cytokines (VEGF, BFGF, and TSP) were also compared between cases of familial and sporadic CLL.

Results: Seventy-one families seen at Mayo Clinic were identified meeting criteria for familial CLL. Of the 71 index CLL families, 78.9% (n=56) had at least one other first or second-degree relative with CLL or a B cell LPD, 15.5% (n=11) had 2 other affected members, and 5.6% (n=4) had 3 or more affected members. Of affected family members with B-cell LPDs other than CLL, 64% (n=25) had non-Hodgkin lymphoma, 21% (n=8) had Hodgkin disease, 10% (n=4) had multiple myeloma or Waldenstrom macroglobulinemia, and 5% (n=2) had another lymphoid leukemia (1 ALL, 1 hairy cell leukemia). The median age was 62, with 63% males and 37% females. The majority of individuals had an early Rai stage at diagnosis (stage 0–66%, stage I-19%). Results of cytogenetic testing by FISH, CD38 status, IgV_H gene mutation status appear similar in familial and sporadic CLL cases seen at Mayo clinic during the same time interval. No clear pattern of IgV_H gene mutation status, IgV_H gene family usage, level of CD38 expression, or cytogenetic abnormalities by FISH was seen among multiple affected members from the same family. There were also no significant differences noted in serum, intracellular, and CLL B cell secreted levels of VEGF, BFGF or TSP in the familial samples when compared to a cohort of non-familial samples.

Conclusions: Expression of cytogenetics by FISH, immunophenotype, IgV_H mutation status and levels of serum, intracellular and cytoplasmic pro- and anti-angiogenic factors(VEGF, BFGF, and TSP) were similar in individuals with familial and sporadic CLL.