A 62-year-old man presented with mucosa-associated lymphoid tissue (MALT) lymphoma manifesting primarily in the oropharyngeal mucosa, bone marrow, and peripheral blood and consequently manifesting a distinct type of secondary skin involvement. At diagnosis, the malignant bone marrow cells showed no chromosomal translocations (including MYC break points) as evidenced by fluorescence in situ hybridization analysis (FISH). Three months later, and 1 week after receiving therapy with rituximab, the patient developed a purpuric exanthema resembling allergic vasculitis (Figure 1A and B). Moreover, his upper arms displayed bluish livedolike lesions (Figure 1C and D). Biopsy specimens from both types of lesions revealed infiltrates of monomorphic lymphoplasmacytoid tumor cells (CD20+, CD79a+, Bcl-2+, λ+, CD5−, CD23−, TdT−, CD34−, CD10−, CD30−, CD138−, and Ki67 proliferation index <3%) (Figure 1E-H). Using a procedure described previously,1,2 we performed interphase FISH on lesional skin biopsy specimens targeting the IGH, IGL, IGK, MYC, BCL6, and MALT1 loci and surprisingly discovered an IGL-MYC fusion, which indicates the presence of the translocation (8;22)(q24;q11) (Figure 2C and Table). Three cycles of chemotherapy with rituximab and cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone followed by rituximab and fludarabine, cyclophosphamide, and mitoxantrone resulted in transient remission only.
Kaune KM, Baumgart M, Gesk S, Middel P, Ghadimi BM, Siebert R, Bertsch HP, Schön MP, Neumann C. Secondary Cutaneous Vasculitislike MALT Lymphoma With an IGL-MYC Fusion. Arch Dermatol. 2009;145(8):955-958. doi:10.1001/archdermatol.2009.166