Cytomorphologic findings of B-cell lymphomas with concurrent IGH/BCL2 and MYC rearrangements (dual-translocation lymphomas).

Background: B-cell lymphomas with concurrent IGH/BCL2 and MYC gene rearrangements, termed dual-translocation or double-hit lymphomas (DTLs), rarely are identified. They usually are characterized by highly aggressive behavior, a poor prognosis, and complex karyotypes. The objective of this study was to review and describe the cytomorphologic findings in different types of cytologic preparations and clinicopathologic characteristics of patients with DTLs.

Methods: Patient samples with IGH/BCL2 and MYC rearrangements that were detected by fluorescence in situ hybridization during the period from October 2003 to September 2009 were selected for morphology review. Clinical data and results from additional studies were collected from patient reports.

Results: Cytologic samples from 14 patients (5 men and 9 women) were reviewed. The most common cytomorphologic pattern was a mixed cell population consisting predominantly of large cells (88.2%), mainly centroblasts (94.1%), with dark blue cytoplasm (76.4%) accompanied by apoptotic bodies (64.7%), with marked cellular pleomorphism (94.1%). Nuclear segmentation was present in 64.7% of samples, conferring a "coffee bean" nucleus, and cytoplasmic vacuoles were observed in 46.6% of samples. Immunophenotyping revealed the expression of CD20, CD19, surface immunoglobulin, and CD10 in 13 samples. Other chromosomal aberrations were also identified. Seven patients died of their disease, and the time from progression to death ranged from 1 month to 16 months.

Conclusions: Large cells with deeply basophilic cytoplasm, cytoplasmic vacuoles, and frequent segmented nuclei, particularly in fine needle aspirate smears and especially in patients with clinically aggressive and/or unusual clinical features, should trigger a fluorescence in situ hybridization analysis for IGH/BCL2 and MYC translocation to identify this entity.