CD19 CAR-T Therapy Produces Durable Remission in TP53-Mutated, Triple-Refractory Burkitt Lymphoma

The patient was a 16-year-old adolescent male. He first presented with recurrent abdominal pain. Based on initial evaluation, he was diagnosed with high-grade B-cell lymphoma. Later reevaluation of the tumor tissue reclassified the diagnosis as Burkitt lymphoma carrying a TP53 mutation. At diagnosis, his serum lactate dehydrogenase (LDH), an enzyme measured in blood that rises with rapid tissue turnover, was markedly elevated at 1,343 U/L, and his lymphoma cells expressed the CD19 surface marker, the protein later targeted by CAR-T therapy. The specific disease stage was not reported in the source case description.

The patient presented with recurrent abdominal pain. No further details of physical examination findings, imaging results, or symptom duration prior to diagnosis were reported in the source case.

Initial pathology review led to a diagnosis of high-grade B-cell lymphoma. After the disease proved refractory to multiple treatment lines, the case was reevaluated, and the diagnosis was revised to Burkitt lymphoma with a confirmed TP53 mutation. Baseline LDH was markedly elevated at 1,343 U/L, and the tumor cells expressed CD19. The source did not report formal disease stage.

The patient received three sequential chemoimmunotherapy regimens, each followed by disease refractoriness or progression: DA-EPOCH-R (first line), AZA plus R-CDOP (second line), and R-CODOX-M (third line, after which disease progressed). Following confirmation of Burkitt lymphoma with TP53 mutation, he received CD19-directed CAR-T cell therapy using axicabtagene ciloleucel (Axi-cel).

Following CAR-T cell infusion, the patient achieved a complete metabolic response (CMR), indicating resolution of metabolically active disease on imaging performed after treatment.

As of the most recent reported follow-up in March 2025, the patient remained in remission 30 months after CAR-T cell infusion. The report describes full functional recovery, including resumption of normal academic life.

This case documents an adolescent with TP53-mutated Burkitt lymphoma who failed three sequential chemoimmunotherapy regimens before achieving a complete metabolic response and durable remission following CD19-directed CAR-T therapy. The available evidence offers a biologically coherent, though not directly proven, explanation for this sequence. TP53 mutation is an established predictor of chemoresistance in aggressive B-cell lymphoma, consistent with this patient's repeated treatment failures with DA-EPOCH-R, AZA plus R-CDOP, and R-CODOX-M. The subsequent response to CAR-T is plausible because CAR-T cells kill target cells predominantly through granzyme B/perforin and Fas/FasL pathways that do not require an intact p53-dependent intrinsic apoptosis cascade, and documented CAR-T resistance mechanisms center on antigen loss and T-cell dysfunction rather than tumor-intrinsic apoptotic defects. This mechanistic dissociation, however, has not been demonstrated directly in Burkitt lymphoma cells or in this patient's tumor; it is inferred from DLBCL, general immunology, and in vitro biochemical literature. The diagnostic reclassification from high-grade B-cell lymphoma to Burkitt lymphoma reflects a known overlap in morphology between these entities; TP53 mutation status did not and could not have resolved that ambiguity, since it is neither a WHO diagnostic criterion for Burkitt lymphoma nor specific to it. The markedly elevated baseline LDH is consistent with the glycolytic, MYC-driven phenotype expected in Burkitt lymphoma, but this patient's favorable, durable outcome runs counter to LDH-based prognostic associations reported in DLBCL cohorts treated with CD19 CAR-T, where high baseline LDH has predicted inferior outcomes. Finally, the specific efficacy and durability of axicabtagene ciloleucel in adolescent, relapsed/refractory Burkitt lymphoma is not established by existing trial evidence, which was generated in adult patients with other aggressive B-cell lymphoma subtypes; this case adds a single data point rather than generalizable confirmation.

The strongest and most consistent thread across the supporting evidence is mechanistic: cytotoxic lymphocyte killing, whether from natural CD8+ T cells or engineered CAR-T cells, can proceed through granzyme B/perforin-mediated pathways that bypass the p53-dependent intrinsic apoptosis cascade disrupted in this patient's tumor. This is supported by foundational immunology, biochemical work on granzyme B cleavage of Bid, and reviews of documented CAR-T resistance mechanisms, none of which identify tumor-intrinsic apoptotic status as a primary determinant of CAR-T failure. This body of evidence is coherent but indirect: it was generated in DLBCL, other cell systems, or general immunology contexts, not in Burkitt lymphoma or in this patient's own cells. An alternative, non-exclusive explanation is that this patient's outcome depended more on the quality of the CAR-T product itself, its antigen recognition and T-cell polyfunctionality, than on any reversal of the apoptotic defect underlying chemoresistance; the evidence on CAR-T efficacy determinants points toward product fitness and tumor microenvironment factors as being at least as influential as tumor apoptotic pathway integrity. On the diagnostic side, the evidence is fairly clear that TP53 mutation status was not the source of, nor the resolution to, the initial misdiagnosis: WHO criteria for Burkitt lymphoma rest on MYC rearrangement and morphology/immunophenotype, and TP53 mutations are neither specific to Burkitt lymphoma nor exclusive to it. The metabolic question is the least settled. MYC-driven glycolytic reprogramming offers a plausible mechanism for the elevated LDH observed here, but the clinical literature linking high baseline LDH to inferior CD19 CAR-T outcomes comes entirely from DLBCL cohorts, and this patient's markedly elevated LDH did not track with a poor outcome. Rather than treating this as disconfirming evidence against LDH's prognostic value generally, it is more accurately read as a reminder that a single case cannot establish or refute a population-level association, and that LDH's prognostic meaning in Burkitt lymphoma specifically has not been directly studied in the CAR-T setting. Overall, this case is best understood as consistent with, rather than proof of, the proposed apoptosis-bypass and antigen-driven efficacy mechanisms; the evidence supporting those mechanisms is drawn substantially from adjacent disease contexts rather than from Burkitt lymphoma itself.

As a single case report, this account cannot establish generalizable efficacy, durability, or mechanistic conclusions; outcomes in one patient may reflect chance, unmeasured host or tumor factors, or product-specific variables that would not recur in other patients. The underlying case source did not report disease stage, exact treatment dates, detailed CAR-T product characteristics, or laboratory data beyond baseline LDH, limiting the granularity of any biological inference. Nearly all of the supporting mechanistic and clinical evidence cited here originates from diffuse large B-cell lymphoma, other aggressive B-cell lymphoma subtypes, adult populations, or in vitro/non-lymphoma systems rather than from Burkitt lymphoma or adolescent patients specifically, so extrapolation to this case's exact biology carries substantial uncertainty. This analysis is a secondary review restricted to a predefined, non-exhaustive set of verified evidence items and does not represent an exhaustive literature search; additional relevant studies could alter the assessment presented here.

The source case report does not include a first-person account from the patient. The only patient-level outcome detail beyond clinical remission is that he resumed normal academic life following treatment, as reported at the 30-month follow-up.