Large-cell transformation of a composite lymphoma

High-grade B-cell lymphoma with MYC and BCL2 rearrangements arising in a composite lymphoma

Background

We report the first case of composite lymphoma consisting of chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL), follicular lymphoma (FL) and high-grade B-cell lymphoma with MYC and BCL2 rearrangements within the same needle biopsy in which a clonal relationship between the FL and high-grade B-cell lymphoma components was demonstrated by molecular cytogenetics.

Case presentation

An 85-year-old man presented with masses in his neck and right groin. Cutting needle biopsy of the inguinal mass revealed the three lymphoma types which were morphologically, immunophenotypically and topographically distinct. Fluorescence in situ hybridization (FISH) identified an IGH-BCL2 rearrangement in both the FL and high-grade B-cell components while a MYC rearrangement was detected in the high-grade B-cell component alone.

Conclusions

Our findings suggest that the high-grade lymphoma with MYC and BCL2 translocations evolved through transformation of the FL by a process that entailed acquisition of the MYC translocation. No clonal relationship between the FL and CLL/SLL components was evident since the IGH-BCL2 rearrangement was present in in the former but not the latter. This unique case of co-localized FL, CLL/SLL, and high-grade B-cell lymphoma contributes to our understanding of the clonal relationships that may exist between the components of composite lymphomas.

Composite Small Lymphocytic Lymphoma/Chronic Lymphocytic Leukemia and Follicular Lymphoma: A Clinicopathological Study of Six Cases

Background: Composite small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) and follicular lymphoma (FL) is extremely rare, and only 13 cases have been reported previously. Methods: We identified 6 cases of composite SLL/CLL and FL in our database and studied their clinical, histologic, immunophenotypic, and cytogenetic features. A literature review of the existing cases was also conducted. Results: The patients included 4 males and 2 females, with a median age of 72 years. Four patients presented with lymphadenopathy and 2 with extranodal diseases. Lymphocytosis was seen in 2 cases. Serum lactate dehydrogenase levels were within normal range in all but one case. There were 2 histologic patterns: SLL/CLL predominant pattern (type I) and FL predominant or mixed pattern (type II). The type I pattern was exclusively associated with in situ follicular neoplasia (ISFN). The SLL/CLL showed typical morphology and immunophenotype in all the cases. The FL component included low grade (n = 3), ISFN (n = 2), and primary cutaneous FL (n = 1). Four cases had staging bone marrow biopsies including 3 cases with involvement by SLL/CLL and 1 case with involvement by SLL/CLL and FL. Four patients received treatments, one was under clinical surveillance, and one had no available information. All patients were alive after a median follow-up of 22 months. Conclusions: This is the largest case serial of composite SLL/CLL and FL. The CL affects elderly individuals, presents with advanced clinical stage, and appears to have a relatively indolent clinical course.