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The differential intensity of FDG-avid lesions, along with acute and chronic symptoms and iron deficiency anemia caused by intestine involvement, was suspect for distinct disease entities, and consequently the axilla and colon lesions were biopsied. The intensity PET-CT projection showed multiple lesions with varying maximum standardized uptake values (SUVmax), indicating that these lesions reflect different disease entities (Figure 1(A,B)). These two lesions were biopsied and it has been assumed that these represent all other lesions with comparable FDG-avidity because taking more biopsies is not patient friendly, clinically inefficient and the chances of having a third synchronous lymphoma are negligibly small. The presented unique case demonstrated this individualized approach for both lymphoma subtypes and anatomical sites by adjuvant radiotherapy of the axillary PET avid lesions and the initiation of LR for the persistent MCL bowel lesions. [Extracted from the article]

The idiotypes of B cell lymphomas represent tumor-specific antigens. T cell responses induced by idiotype vaccination in vivo are directed predominantly against CDR peptides, whereas in vitro T cells also recognize framework-derived epitopes. To investigate the mechanisms regulating the specificity of idiotype-specific T cells, BALB/c or B10.D2 mice were immunized with mature dendritic cells loaded with H-2K-restricted peptides from influenza hemagglutinin, or from shared (J region) or unique (CDR3) structures of the A20 lymphoma idiotype. Antigen-specific T cells were induced in vivo by the CDR3 and influenza epitopes, but not by the J peptide. Gene expression profiling of splenic regulatory T cells revealed vaccination-induced Treg activation and proliferation. Treg activity involved J epitope-dependent IL-10 secretion and functional suppression of peptide-specific effector T cells. Vaccination-induced in vivo proliferation of transgenic hemagglutinin-specific T cells was suppressed by co-immunization with the J peptide and was restored in CD25-depleted animals. In conclusion, Treg induced by a shared idiotype epitope can systemically suppress T cell responses against idiotype-derived and immunodominant foreign epitopes in vivo. The results imply that tumor vaccines should avoid epitopes expressed by normal cells in the draining lymph node to achieve optimal anti-tumor efficacy. [ABSTRACT FROM AUTHOR]