incremental value of fdg pet/ct in aggressive high grade b cell lymphoma with tdt expression

High-grade b-cell lymphoma, an aggressive form of non-hodgkin’s lymphoma, is known as a double or triple hit lymphoma based on the presence of myc and bcl2 without or with bcl6 genetic rearrangements, respectively. it carries a poorer prognosis, compared to other variants of b-cell lymphoma, and its management also differs which requires more intensive chemotherapy in contrast to the routine regimen. terminal deoxynucleotidyl transferase (tdt), a marker of immaturity is commonly expressed in b-cell lymphoblastic leukemia or lymphoma (b cell all) which is absent in mature forms of b-cell lymphoma. the tdt is expressed in high-grade b-cell lymphoma; therefore, it poses a classification and management dilemma, which should be accurately differentiated from b-cell all and mandates molecular analysis. herein, we report a case of a 52-year-old female with biopsy reported as high-grade b-cell lymphoma with tdt expression. she was referred for fluor-deoxyglucose (fdg) positron emission tomography-computed tomography (pet/ct) scan for staging in the absence of molecular analysis for b-cell all. it was diagnosed as lymphoma on fdg pet/ct based on its characteristic findings of extensive extranodal involvement of multiple organs with no significant lymphadenopathy establishing the incremental value of fdg pet/ct scan, which helped the clinician to arrive at a conclusion.