Abstract Multiple myeloma (MM) is the second most common hematological malignancy in the United States, and represents one percent of all cancers. Despite ongoing research, MM remains incurable, with an average life expectancy of five to eight years after diagnosis. In order to better understand MM development, our lab has created a novel mouse model of plasmacytoma (PCT) which mimics key features of MM. This mouse model contains two transgenes. The first recapitulates a T(12:15) Myc translocation, while the second is a copy of human IL-6. The resultant mouse, designated iMyc/IL-6, develops PCT around three months of age with full tumor penetrance. Interestingly, both IL-6 and iMyc/IL-6 mice develop robust spontaneous germinal centers (GC) by two months of age. Notably, the addition of the iMyc oncogene in iMyc/IL-6 mice results in an increased frequency of GC B cells. Correlating with the development of spontaneous GCs, both IL-6 and iMyc/IL-6 mice develop a robust follicular T helper (Tfh) cell response which becomes more pronounced as mice develop tumors. These results may provide important clues into the role of the T cell response in the development of MM. Our current research is focused on elucidating the role of the Tfh response in the development of PCT.