The only somatic genetic aberrancies correlating with inferior progression-free survival (PFS) were TP53 mutations (HR, 3.1; 95% CI, 1.4-6.8; P=.005) and TP53/17p deletions (HR, 4.1; 95% CI, 1.1-15.0, P=.03). PFS remained inferior when stratifying by TP53 mutation status, with a median PFS of 4.5 months (95% CI, 3.8-13.9) for PTCL with a TP53 mutation (n=21) vs 10.5 months (95% CI, 7.8-18.1; P<.001) for PTCL without a TP53 mutation (n=111)....This retrospective study suggests patients with PTCL with TP53 mutations experience inferior PFS when treated with curative-intent chemotherapy, warranting prospective confirmation.