The purpose of this study is to find out if the experimental product, axi-cel, is safe and effective in treating your lymphoma, compared to standard of care (SOC) therapy (chemotherapy), which includes either R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone) or DA EPOCH R (dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab). The experimental treatment would involve removing some of your immune cells, genetically engineering those cells to identify cancer, receiving additional therapy while you wait for those cells to...