A study sought to explore the impact of intratumoral T-cell receptor (TCR) repertoire on interim positron emission tomography (iPET) scans, as TCR is associated with improved survival in diffuse large B-cell lymphoma (DLBCL). The findings were published in Clinical & Translational Immunology.
To conduct this study, researchers started by sequencing the third complementarity-determining region of TCR? in tumor samples, blood at pre-therapy and after four cycles of rituximab, cyclophosphamide, doxorubicin, prednisolone, and vincristine (R-CHOP) chemoimmunotherapy in 35 high-risk DLBCL patients.
Following analysis, the results showed that compared with iPET-negative patients, the intratumoral TCR repertoire in iPET-positive patients demonstrated higher cumulative frequency of abundant clonotypes and higher productive clonality. The researchers noted that there was a variable overlap between circulating and intratumoral repertoires, with the dominant intratumoral clonotypes more likely to be detected in the blood.
“This study demonstrates that clonally expanded intratumoral TCR repertoires are associated with iPET-positive [scans] and that the blood can be used to track tumor-associated antigen-specific clonotypes,” the researchers concluded. “These findings assist the rationale design and therapeutic monitoring of immunotherapeutic strategies in DLBCL.”
