Secondary Acute Myeloid Leukemia with Shared TP53 Mutation Following Zanubrutinib-Rituximab for High-Risk Mantle Cell Lymphoma: Clonal Evolution or Treatment Effect?

Secondary Acute Myeloid Leukemia with Shared TP53 Mutation Following Zanubrutinib-Rituximab for High-Risk Mantle Cell Lymphoma: Clonal Evolution or Treatment Effect? | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Secondary Acute Myeloid Leukemia with Shared TP53 Mutation Following Zanubrutinib-Rituximab for High-Risk Mantle Cell Lymphoma: Clonal Evolution or Treatment Effect? Ahmed S. Mohamed, Shibhani Rajanna, Maggie James, Umang Gupta, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8897690/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Secondary myeloid neoplasms have been reported with ibrutinib and acalabrutinib but not with zanubrutinib. We present a female patient in her late 80s with TP53-deleted pleomorphic mantle cell lymphoma who achieved metabolic complete remission with zanubrutinib-rituximab but remained MRD-positive for TP53. Eighteen months later, she developed AML harboring TP53, NPM1, FLT3-TKD, and DNMT3A mutations. The shared TP53 mutation and persistent MRD suggest clonal evolution from a common hematopoietic progenitor rather than drug-induced leukemogenesis, though zanubrutinib's potential role in facilitating this evolution through immunosuppression and clonal selection cannot be excluded. Mantle cell lymphoma acute myeloid leukemia zanubrutinib TP53 mutation clonal evolution therapy-related myeloid neoplasm Introduction Mantle cell lymphoma is an aggressive B-cell non-Hodgkin lymphoma characterized by the t(11;14)(q13;q32) translocation resulting in cyclin D1 overexpression. TP53 mutations, present in 20–30% of cases, represent the single most important molecular predictor of poor outcome, conferring primary refractoriness to conventional therapies and dramatically shortened survival. BTK inhibitors have revolutionized MCL treatment, with zanubrutinib demonstrating high efficacy and favorable tolerability as a highly selective second-generation agent. While second primary malignancies occur in 9–22% of patients receiving BTK inhibitors, the specific risk of secondary myeloid neoplasms varies by agent. [ 1 ] MDS/AML has been reported with ibrutinib in the SHINE trial and is listed in the ibrutinib prescribing information, yet no cases of secondary myeloid neoplasms have been reported with zanubrutinib in clinical trials or post-marketing surveillance. [ 2 – 3 ] We present the first reported case of secondary AML developing after zanubrutinib-rituximab therapy for MCL, examining whether this represents treatment-induced leukemogenesis or clonal evolution from pre-existing TP53-mutated hematopoiesis. Case Presentation A female patient in her late 80s presented in 2023 with severe symptomatic anemia (hemoglobin 5.5 g/dL). Gastrointestinal bleeding and hemolysis were systematically excluded. Staging revealed infradiaphragmatic nodal disease, splenomegaly, and extranodal involvement. Two bone marrow biopsies were attempted: the first resulted in a dry tap suggestive of marrow infiltration, and the second was complicated by bleeding. Lymph node biopsy confirmed pleomorphic MCL: positive for CD5, CD19, CD20, CD38, BCL-2, and CD43; negative for CD10, CD23, CD11c, and CD200; lambda light chain restriction; and FISH positive for IGH-CCND1 translocation. Next-generation sequencing revealed an ultra-high-risk molecular profile including somatic mutations in ID3, BIRC3, KMT2C, NTRK3, and SMC1A; chromosomal abnormalities including 17p deletion (TP53 locus), CDKN2A/2B deletion, and complex karyotype; possible germline ATM and DPYD mutations; markedly increased CCND1 and SOX11 mRNA; Ki-67 of 25%; and LDH of 476 U/L. She was treated with zanubrutinib 160 mg twice daily continuously plus rituximab. Serial PET-CT assessments demonstrated excellent metabolic response: Deauville 3 at 3 months, Deauville 2 at 9 months, and Deauville 1 at 14 months. Despite achieving complete metabolic remission, peripheral blood MRD monitoring remained persistently positive for the TP53-mutated clone throughout treatment. Approximately 18–24 months after MCL diagnosis, the patient developed AML with mutations in TP53 (shared with the MCL clone), NPM1, FLT3-TKD, KMT2C, DNMT3A, ZRSR2, CTNNB1, PIK3CA, BCORL1, and possibly germline DPYD. Discussion This case presents a diagnostic challenge: determining whether the secondary AML represents a treatment-related adverse event of zanubrutinib or clonal evolution from the underlying TP53-mutated disease biology. The Case for Zanubrutinib-Induced Leukemogenesis All BTK inhibitors carry warnings for second primary malignancies, and the class effect cannot be dismissed. In pooled analyses of CLL patients receiving BTK inhibitors, second cancers occur in 9-22% of patients, with an observed-to-expected ratio of 2.2, indicating significantly elevated risk compared to the general population. [1] Acalabrutinib demonstrates a similar pattern, with second primary malignancies occurring in 12-18% of patients across pooled analyses of over 1,000 patients. [4] In the ELEVATE-TN trial, second primary malignancies occurred in 11% of patients receiving acalabrutinib-obinutuzumab and 9% with acalabrutinib monotherapy, compared to 8% with chlorambucil-obinutuzumab. [5] More recently, the AMPLIFY trial demonstrated that second primary cancers were more common with acalabrutinib-venetoclax combinations (4.2-5.2%) than with chemoimmunotherapy (0.8%), suggesting that prolonged BTK inhibitor exposure may contribute to malignancy risk through mechanisms distinct from chemotherapy-induced DNA damage [6]. While zanubrutinib has not been specifically associated with secondary myeloid neoplasms, this may reflect shorter follow-up duration since its FDA approval in 2019, a smaller exposed population reducing statistical power to detect rare events, or reporting bias given that the first case must be reported for a signal to emerge. Several biological mechanisms could plausibly link BTK inhibitor therapy to myeloid leukemogenesis. BTK is expressed not only in B cells but also in myeloid cells, where it regulates innate immune responses, inflammasome activation, and phagocytosis. Chronic BTK inhibition causes profound immunomodulation, including reduced NK cell cytotoxicity, impaired T-cell function, and decreased immunoglobulin levels. This immunosuppressed state may permit expansion of pre-leukemic clones that would otherwise be eliminated by immune surveillance. BTK inhibitor therapy also exerts strong selective pressure on the hematopoietic compartment. Studies using droplet-microfluidic technology have demonstrated that ibrutinib-resistant subclones are detectable at low levels in pretreatment samples, indicating that therapy causes clonal selection and expansion rather than de novo mutagenesis. While this has been studied primarily for BTK-mutant CLL clones, the same principle could apply to TP53-mutated hematopoietic stem cells. By eliminating competing clones, zanubrutinib may have created a selective advantage for the TP53-mutated progenitor, accelerating its expansion and eventual transformation. The temporal relationship—AML developing during active zanubrutinib therapy with an 18-24 month latency—is consistent with therapy-related myeloid neoplasms. Critically, the absence of evidence is not evidence of absence; this case may represent the first signal of a previously unrecognized risk. The Case for TP53-Driven Clonal Evolution The presence of TP53 mutation in both the MCL and subsequent AML, with persistent TP53-positive MRD during MCL remission, provides compelling molecular evidence for a common clonal origin. TP53 mutations are present in only 5-10% of de novo AML cases, making the probability of two independent TP53-mutated malignancies arising by chance exceedingly low. Landmark studies have fundamentally changed our understanding of therapy-related myeloid neoplasms by demonstrating that TP53 mutations in t-AML are not induced by chemotherapy but rather represent pre-existing rare hematopoietic stem/progenitor cells that are resistant to therapy and expand preferentially after treatment. [7-8] In one pivotal study, the exact TP53 mutation found at t-AML diagnosis was detected at low frequencies of 0.003-0.7% in samples obtained 3-6 years before t-AML development, including cases where TP53 mutations were present before any chemotherapy was administered. [7] This patient's MCL harbored 17p deletion at diagnosis, and the persistent MRD positivity for TP53 throughout treatment indicates the clone was never eradicated—it was merely suppressed while the lymphoma component responded to therapy. The AML's mutational signature is highly consistent with transformation from TP53-mutated clonal hematopoiesis. DNMT3A mutations are the most common mutations in clonal hematopoiesis and frequently co-occur with TP53 in therapy-related AML. In patients with clonal hematopoiesis who transformed to AML, four of six had TP53 mutations at CH with expansion of the clone at transformation, and two acquired NPM1 mutations while one acquired FLT3 mutations—a pattern strikingly similar to our patient. [9] Recent mechanistic studies have confirmed that while monoallelic TP53 mutations confer clonal fitness and therapy resistance, biallelic TP53 mutations are essential for leukemic transformation, causing the genomic instability that permits acquisition of additional driver mutations. [10] Importantly, while BTK inhibitors as a class are associated with second primary malignancies, the data from acalabrutinib studies reveal that only 1% of these second malignancies are hematologic, with the vast majority (55% in ELEVATE-TN) being non-melanoma skin cancers. [4-5] This pattern suggests that BTK inhibitors predominantly increase the risk of solid tumors and skin cancers rather than myeloid neoplasms, supporting the hypothesis that our patient's AML arose from her underlying TP53-mutated biology rather than from a BTK inhibitor class effect on myeloid progenitors. Perhaps most compellingly, the TRIANGLE trial demonstrated that secondary hematological malignancies (1 AML, 1 MDS) occurred only in the chemotherapy-alone arm, not in the ibrutinib-containing arms [3]. Similarly, the GAIA/CLL13 trial showed that second primary cancers occurred in 29% of patients receiving chemoimmunotherapy versus only 15-17% in venetoclax-based arms [11]. This strongly suggests that BTK inhibitors and targeted therapies are less leukemogenic than conventional chemotherapy, not more. The complete absence of myeloid neoplasm reports with zanubrutinib—in contrast to the documented cases with ibrutinib—argues against a drug-specific effect. The molecular evidence overwhelmingly favors clonal evolution from a pre-existing TP53-mutated hematopoietic progenitor as the primary mechanism. The shared TP53 mutation, persistent MRD positivity, mutational profile consistent with CH-derived AML, and dramatically lower t-MN rates with BTK inhibitors compared to chemotherapy all point toward disease biology rather than drug toxicity. However, zanubrutinib therapy may have contributed indirectly by creating selective pressure favoring expansion of the TP53-mutated clone, inducing immunosuppression that impaired surveillance against the emerging leukemic cells, and eliminating competing clones to provide a fitness advantage to the TP53-mutated progenitor. In this model, zanubrutinib did not cause the AML through direct mutagenesis but may have facilitated its emergence by altering the competitive landscape of hematopoiesis. The persistent TP53-positive MRD throughout treatment was, in retrospect, a harbinger of what was to come. Despite achieving Deauville 1 on PET-CT, the TP53-mutated clone persisted in the peripheral blood. This dissociation between metabolic response and molecular response indicates that the TP53-mutated progenitor was never eliminated despite the lymphoma component responding wellto therapy, but the ancestral clone from which it arose remained, quietly accumulating additional mutations until it emerged as AML. Conclusion We report, perhaps the first case of secondary AML following zanubrutinib-rituximab therapy for MCL. The molecular evidence, including shared TP53 mutation, persistent TP53-positive MRD during MCL remission, and a mutational profile consistent with clonal hematopoiesis-derived AML, strongly supports clonal evolution from a common TP53-mutated hematopoietic progenitor rather than direct drug-induced leukemogenesis. However, zanubrutinib's potential role in facilitating this evolution through immunosuppression and clonal selection cannot be entirely excluded. This case highlights several important clinical lessons. First, TP53-mutated MCL represents ultra-high-risk disease with potential for clonal evolution to myeloid neoplasms from a common hematopoietic progenitor. Second, persistent MRD positivity for TP53 despite metabolic remission may indicate ongoing clonal hematopoiesis at risk for transformation and should prompt enhanced surveillance. Third, secondary AML following BTK inhibitor therapy may represent disease biology rather than treatment toxicity, but the distinction requires careful molecular analysis including assessment for shared mutations between the two malignancies. Finally, the absence of prior reports of myeloid neoplasms with zanubrutinib, in contrast to ibrutinib, suggests this case more likely reflects disease biology than a drug class effect, though pharmacovigilance reporting remains important. As BTK inhibitors become increasingly used in frontline settings, careful attention to the emergence of secondary myeloid neoplasms and rigorous molecular characterization, when they occur will be essential to distinguish true drug toxicity from the natural history of genetically unstable disease. Declarations Funding: There was no funding for this paper. Consent to Publish: Written informed consent was obtained from the patient for publication of this case report. Ethics Declaration: Not applicable. Conflicts of Interest: The authors declare no conflicts of interest. Author Contributions: ASM conceptualized the case report and wrote the original draft. SR, MJ, UG, and SA contributed to the critical revision of the manuscript. SW provided supervision and final approval. All authors reviewed and approved the final manuscript. References Bond DA, Huang Y, Fisher JL, Ruppert AS, Owen DH, Woyach JA et al (2020) Second cancer incidence in CLL patients receiving BTK inhibitors. Leukemia 34(12):3197–3205 Song Y, Zhou K, Zou D, Zhou J, Hu J, Yang H et al (2022) Zanubrutinib in relapsed/refractory mantle cell lymphoma: long-term efficacy and safety results from a phase 2 study. Blood 139(21):3148–3158 Dreyling M, Doorduijn J, Giné E, Hornberg M, Chanan-Khan A, Qian J et al (2024) Ibrutinib combined with immunochemotherapy with or without autologous stem-cell transplantation versus immunochemotherapy and autologous stem-cell transplantation in previously untreated patients with mantle cell lymphoma (TRIANGLE): a three-arm, randomised, open-label, phase 3 superiority trial of the European Mantle Cell Lymphoma Network. Lancet 403(10441):2293–2306 Furman RR, Byrd JC, Owen RG, O'Brien SM, Brown JR, Hillmen P et al (2021) Pooled analysis of safety data from clinical trials evaluating acalabrutinib monotherapy in mature B-cell malignancies. Leukemia 35(11):3201–3211 Sharman JP, Egyed M, Jurczak W, Skarbnik A, Pagel JM, Flinn IW et al (2020) Acalabrutinib with or without obinutuzumab versus chlorambucil and obinutuzumab for treatment-naive chronic lymphocytic leukaemia (ELEVATE-TN): a randomised, controlled, phase 3 trial. Lancet 395(10232):1278–1291 Brown JR, Seymour JF, Jurczak W, Bolen CR, Gong Y, Knapp A et al (2025) Fixed-duration acalabrutinib combinations in untreated chronic lymphocytic leukemia. N Engl J Med 392(8):748–762 Wong TN, Ramsingh G, Young AL, Miller CA, Tober W, Welch JS et al (2015) Role of TP53 mutations in the origin and evolution of therapy-related acute myeloid leukaemia. Nature 518(7540):552–555 Takahashi K, Wang F, Kantarjian H, Doss D, Khanna K, Thompson E et al (2017) Preleukaemic clonal haemopoiesis and risk of therapy-related myeloid neoplasms: a case-control study. Lancet Oncol 18(1):100–111 Braish J, Li Z, Loghavi S, Takahashi K, Kantarjian H, Garcia-Manero G et al (2024) Genomic evolution of patients with myeloid neoplasms and known antecedent clonal hematopoiesis. J Clin Oncol 42(16 suppl):6584 Fullin J, Topçu E, Zielińska KA, Tzankov A, Manz MG, Schwaller J et al (2025) The pathogenesis of therapy-related myeloid neoplasms from TP53-mutant clonal hematopoiesis. Leukemia. 10.1038/s41375-025-02839-5 Epub ahead of print Fürstenau M, Kater AP, Robrecht S, von Tresckow J, Zhang C, Niemann CU et al (2024) First-line venetoclax combinations versus chemoimmunotherapy in fit patients with chronic lymphocytic leukaemia (GAIA/CLL13): 4-year follow-up from a multicentre, open-label, randomised, phase 3 trial. Lancet Oncol 25(6):744–759 Additional Declarations No competing interests reported. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8897690","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":595683612,"identity":"425fe929-2289-4221-b16b-31e5e73447ae","order_by":0,"name":"Ahmed S. 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TP53 mutations, present in 20\u0026ndash;30% of cases, represent the single most important molecular predictor of poor outcome, conferring primary refractoriness to conventional therapies and dramatically shortened survival. BTK inhibitors have revolutionized MCL treatment, with zanubrutinib demonstrating high efficacy and favorable tolerability as a highly selective second-generation agent.\u003c/span\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eWhile second primary malignancies occur in 9\u0026ndash;22% of patients receiving BTK inhibitors, the specific risk of secondary myeloid neoplasms varies by agent.\u003c/span\u003e [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eMDS/AML has been reported with ibrutinib in the SHINE trial and is listed in the ibrutinib prescribing information, yet no cases of secondary myeloid neoplasms have been reported with zanubrutinib in clinical trials or post-marketing surveillance.\u003c/span\u003e [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e] \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eWe present the first reported case of secondary AML developing after zanubrutinib-rituximab therapy for MCL, examining whether this represents treatment-induced leukemogenesis or clonal evolution from pre-existing TP53-mutated hematopoiesis.\u003c/span\u003e\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eA female patient in her late 80s presented in 2023 with severe symptomatic anemia (hemoglobin 5.5 g/dL). Gastrointestinal bleeding and hemolysis were systematically excluded. Staging revealed infradiaphragmatic nodal disease, splenomegaly, and extranodal involvement. Two bone marrow biopsies were attempted: the first resulted in a dry tap suggestive of marrow infiltration, and the second was complicated by bleeding.\u003c/span\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eLymph node biopsy confirmed pleomorphic MCL: positive for CD5, CD19, CD20, CD38, BCL-2, and CD43; negative for CD10, CD23, CD11c, and CD200; lambda light chain restriction; and FISH positive for IGH-CCND1 translocation. Next-generation sequencing revealed an ultra-high-risk molecular profile including somatic mutations in ID3, BIRC3, KMT2C, NTRK3, and SMC1A; chromosomal abnormalities including 17p deletion (TP53 locus), CDKN2A/2B deletion, and complex karyotype; possible germline ATM and DPYD mutations; markedly increased CCND1 and SOX11 mRNA; Ki-67 of 25%; and LDH of 476 U/L.\u003c/span\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eShe was treated with zanubrutinib 160 mg twice daily continuously plus rituximab. Serial PET-CT assessments demonstrated excellent metabolic response: Deauville 3 at 3 months, Deauville 2 at 9 months, and Deauville 1 at 14 months. Despite achieving complete metabolic remission, peripheral blood MRD monitoring remained persistently positive for the TP53-mutated clone throughout treatment.\u003c/span\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eApproximately 18\u0026ndash;24 months after MCL diagnosis, the patient developed AML with mutations in TP53 (shared with the MCL clone), NPM1, FLT3-TKD, KMT2C, DNMT3A, ZRSR2, CTNNB1, PIK3CA, BCORL1, and possibly germline DPYD.\u003c/span\u003e \u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis case presents a diagnostic challenge: determining whether the secondary AML represents a treatment-related adverse event of zanubrutinib or clonal evolution from the underlying TP53-mutated disease biology.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe Case for Zanubrutinib-Induced Leukemogenesis\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll BTK inhibitors carry warnings for second primary malignancies, and the class effect cannot be dismissed. In pooled analyses of CLL patients receiving BTK inhibitors, second cancers occur in 9-22% of patients, with an observed-to-expected ratio of 2.2, indicating significantly elevated risk compared to the general population. [1] Acalabrutinib demonstrates a similar pattern, with second primary malignancies occurring in 12-18% of patients across pooled analyses of over 1,000 patients. [4] In the ELEVATE-TN trial, second primary malignancies occurred in 11% of patients receiving acalabrutinib-obinutuzumab and 9% with acalabrutinib monotherapy, compared to 8% with chlorambucil-obinutuzumab. [5] More recently, the AMPLIFY trial demonstrated that second primary cancers were more common with acalabrutinib-venetoclax combinations (4.2-5.2%) than with chemoimmunotherapy (0.8%), suggesting that prolonged BTK inhibitor exposure may contribute to malignancy risk through mechanisms distinct from chemotherapy-induced DNA damage [6]. While zanubrutinib has not been specifically associated with secondary myeloid neoplasms, this may reflect shorter follow-up duration since its FDA approval in 2019, a smaller exposed population reducing statistical power to detect rare events, or reporting bias given that the first case must be reported for a signal to emerge.\u003c/p\u003e\n\u003cp\u003eSeveral biological mechanisms could plausibly link BTK inhibitor therapy to myeloid leukemogenesis. BTK is expressed not only in B cells but also in myeloid cells, where it regulates innate immune responses, inflammasome activation, and phagocytosis. Chronic BTK inhibition causes profound immunomodulation, including reduced NK cell cytotoxicity, impaired T-cell function, and decreased immunoglobulin levels. This immunosuppressed state may permit expansion of pre-leukemic clones that would otherwise be eliminated by immune surveillance.\u003c/p\u003e\n\u003cp\u003eBTK inhibitor therapy also exerts strong selective pressure on the hematopoietic compartment. Studies using droplet-microfluidic technology have demonstrated that ibrutinib-resistant subclones are detectable at low levels in pretreatment samples, indicating that therapy causes clonal selection and expansion rather than de novo mutagenesis. While this has been studied primarily for BTK-mutant CLL clones, the same principle could apply to TP53-mutated hematopoietic stem cells. By eliminating competing clones, zanubrutinib may have created a selective advantage for the TP53-mutated progenitor, accelerating its expansion and eventual transformation. The temporal relationship\u0026mdash;AML developing during active zanubrutinib therapy with an 18-24 month latency\u0026mdash;is consistent with therapy-related myeloid neoplasms. Critically, the absence of evidence is not evidence of absence; this case may represent the first signal of a previously unrecognized risk.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe Case for TP53-Driven Clonal Evolution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe presence of TP53 mutation in both the MCL and subsequent AML, with persistent TP53-positive MRD during MCL remission, provides compelling molecular evidence for a common clonal origin. TP53 mutations are present in only 5-10% of de novo AML cases, making the probability of two independent TP53-mutated malignancies arising by chance exceedingly low.\u003c/p\u003e\n\u003cp\u003eLandmark studies have fundamentally changed our understanding of therapy-related myeloid neoplasms by demonstrating that TP53 mutations in t-AML are not induced by chemotherapy but rather represent pre-existing rare hematopoietic stem/progenitor cells that are resistant to therapy and expand preferentially after treatment. [7-8] In one pivotal study, the exact TP53 mutation found at t-AML diagnosis was detected at low frequencies of 0.003-0.7% in samples obtained 3-6 years before t-AML development, including cases where TP53 mutations were present before any chemotherapy was administered. [7] This patient\u0026apos;s MCL harbored 17p deletion at diagnosis, and the persistent MRD positivity for TP53 throughout treatment indicates the clone was never eradicated\u0026mdash;it was merely suppressed while the lymphoma component responded to therapy.\u003c/p\u003e\n\u003cp\u003eThe AML\u0026apos;s mutational signature is highly consistent with transformation from TP53-mutated clonal hematopoiesis. DNMT3A mutations are the most common mutations in clonal hematopoiesis and frequently co-occur with TP53 in therapy-related AML. In patients with clonal hematopoiesis who transformed to AML, four of six had TP53 mutations at CH with expansion of the clone at transformation, and two acquired NPM1 mutations while one acquired FLT3 mutations\u0026mdash;a pattern strikingly similar to our patient. [9] Recent mechanistic studies have confirmed that while monoallelic TP53 mutations confer clonal fitness and therapy resistance, biallelic TP53 mutations are essential for leukemic transformation, causing the genomic instability that permits acquisition of additional driver mutations. [10]\u003c/p\u003e\n\u003cp\u003eImportantly, while BTK inhibitors as a class are associated with second primary malignancies, the data from acalabrutinib studies reveal that only 1% of these second malignancies are hematologic, with the vast majority (55% in ELEVATE-TN) being non-melanoma skin cancers. [4-5] This pattern suggests that BTK inhibitors predominantly increase the risk of solid tumors and skin cancers rather than myeloid neoplasms, supporting the hypothesis that our patient\u0026apos;s AML arose from her underlying TP53-mutated biology rather than from a BTK inhibitor class effect on myeloid progenitors.\u003c/p\u003e\n\u003cp\u003ePerhaps most compellingly, the TRIANGLE trial demonstrated that secondary hematological malignancies (1 AML, 1 MDS) occurred only in the chemotherapy-alone arm, not in the ibrutinib-containing arms [3]. Similarly, the GAIA/CLL13 trial showed that second primary cancers occurred in 29% of patients receiving chemoimmunotherapy versus only 15-17% in venetoclax-based arms [11]. This strongly suggests that BTK inhibitors and targeted therapies are less leukemogenic than conventional chemotherapy, not more. The complete absence of myeloid neoplasm reports with zanubrutinib\u0026mdash;in contrast to the documented cases with ibrutinib\u0026mdash;argues against a drug-specific effect.\u003c/p\u003e\n\u003cp\u003eThe molecular evidence overwhelmingly favors clonal evolution from a pre-existing TP53-mutated hematopoietic progenitor as the primary mechanism. The shared TP53 mutation, persistent MRD positivity, mutational profile consistent with CH-derived AML, and dramatically lower t-MN rates with BTK inhibitors compared to chemotherapy all point toward disease biology rather than drug toxicity. However, zanubrutinib therapy may have contributed indirectly by creating selective pressure favoring expansion of the TP53-mutated clone, inducing immunosuppression that impaired surveillance against the emerging leukemic cells, and eliminating competing clones to provide a fitness advantage to the TP53-mutated progenitor. In this model, zanubrutinib did not cause the AML through direct mutagenesis but may have facilitated its emergence by altering the competitive landscape of hematopoiesis.\u003c/p\u003e\n\u003cp\u003eThe persistent TP53-positive MRD throughout treatment was, in retrospect, a harbinger of what was to come. Despite achieving Deauville 1 on PET-CT, the TP53-mutated clone persisted in the peripheral blood. This dissociation between metabolic response and molecular response indicates that the TP53-mutated progenitor was never eliminated despite the lymphoma component responding wellto therapy, but the ancestral clone from which it arose remained, quietly accumulating additional mutations until it emerged as AML.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eWe report, perhaps the first case of secondary AML following zanubrutinib-rituximab therapy for MCL. The molecular evidence, including shared TP53 mutation, persistent TP53-positive MRD during MCL remission, and a mutational profile consistent with clonal hematopoiesis-derived AML, strongly supports clonal evolution from a common TP53-mutated hematopoietic progenitor rather than direct drug-induced leukemogenesis. However, zanubrutinib's potential role in facilitating this evolution through immunosuppression and clonal selection cannot be entirely excluded.\u003c/span\u003e \u003c/p\u003e \u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eThis case highlights several important clinical lessons. First, TP53-mutated MCL represents ultra-high-risk disease with potential for clonal evolution to myeloid neoplasms from a common hematopoietic progenitor. Second, persistent MRD positivity for TP53 despite metabolic remission may indicate ongoing clonal hematopoiesis at risk for transformation and should prompt enhanced surveillance. Third, secondary AML following BTK inhibitor therapy may represent disease biology rather than treatment toxicity, but the distinction requires careful molecular analysis including assessment for shared mutations between the two malignancies. Finally, the absence of prior reports of myeloid neoplasms with zanubrutinib, in contrast to ibrutinib, suggests this case more likely reflects disease biology than a drug class effect, though pharmacovigilance reporting remains important. As BTK inhibitors become increasingly used in frontline settings, careful attention to the emergence of secondary myeloid neoplasms and rigorous molecular characterization, when they occur will be essential to distinguish true drug toxicity from the natural history of genetically unstable disease.\u003c/span\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e There was no funding for this paper.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish:\u003c/strong\u003e Written informed consent was obtained from the patient for publication of this case report.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Declaration:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest:\u003c/strong\u003e The authors declare no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u003c/strong\u003e ASM conceptualized the case report and wrote the original draft. SR, MJ, UG, and SA contributed to the critical revision of the manuscript. SW provided supervision and final approval. All authors reviewed and approved the final manuscript.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBond DA, Huang Y, Fisher JL, Ruppert AS, Owen DH, Woyach JA et al (2020) Second cancer incidence in CLL patients receiving BTK inhibitors. Leukemia 34(12):3197\u0026ndash;3205\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSong Y, Zhou K, Zou D, Zhou J, Hu J, Yang H et al (2022) Zanubrutinib in relapsed/refractory mantle cell lymphoma: long-term efficacy and safety results from a phase 2 study. Blood 139(21):3148\u0026ndash;3158\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eDreyling M, Doorduijn J, Gin\u0026eacute; E, Hornberg M, Chanan-Khan A, Qian J et al (2024) Ibrutinib combined with immunochemotherapy with or without autologous stem-cell transplantation versus immunochemotherapy and autologous stem-cell transplantation in previously untreated patients with mantle cell lymphoma (TRIANGLE): a three-arm, randomised, open-label, phase 3 superiority trial of the European Mantle Cell Lymphoma Network. Lancet 403(10441):2293\u0026ndash;2306\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFurman RR, Byrd JC, Owen RG, O'Brien SM, Brown JR, Hillmen P et al (2021) Pooled analysis of safety data from clinical trials evaluating acalabrutinib monotherapy in mature B-cell malignancies. Leukemia 35(11):3201\u0026ndash;3211\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSharman JP, Egyed M, Jurczak W, Skarbnik A, Pagel JM, Flinn IW et al (2020) Acalabrutinib with or without obinutuzumab versus chlorambucil and obinutuzumab for treatment-naive chronic lymphocytic leukaemia (ELEVATE-TN): a randomised, controlled, phase 3 trial. Lancet 395(10232):1278\u0026ndash;1291\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBrown JR, Seymour JF, Jurczak W, Bolen CR, Gong Y, Knapp A et al (2025) Fixed-duration acalabrutinib combinations in untreated chronic lymphocytic leukemia. N Engl J Med 392(8):748\u0026ndash;762\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWong TN, Ramsingh G, Young AL, Miller CA, Tober W, Welch JS et al (2015) Role of TP53 mutations in the origin and evolution of therapy-related acute myeloid leukaemia. Nature 518(7540):552\u0026ndash;555\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eTakahashi K, Wang F, Kantarjian H, Doss D, Khanna K, Thompson E et al (2017) Preleukaemic clonal haemopoiesis and risk of therapy-related myeloid neoplasms: a case-control study. Lancet Oncol 18(1):100\u0026ndash;111\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eBraish J, Li Z, Loghavi S, Takahashi K, Kantarjian H, Garcia-Manero G et al (2024) Genomic evolution of patients with myeloid neoplasms and known antecedent clonal hematopoiesis. J Clin Oncol 42(16 suppl):6584\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eFullin J, Top\u0026ccedil;u E, Zielińska KA, Tzankov A, Manz MG, Schwaller J et al (2025) The pathogenesis of therapy-related myeloid neoplasms from TP53-mutant clonal hematopoiesis. Leukemia. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1038/s41375-025-02839-5\u003c/span\u003e\u003cspan address=\"10.1038/s41375-025-02839-5\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003eEpub ahead of print\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eF\u0026uuml;rstenau M, Kater AP, Robrecht S, von Tresckow J, Zhang C, Niemann CU et al (2024) First-line venetoclax combinations versus chemoimmunotherapy in fit patients with chronic lymphocytic leukaemia (GAIA/CLL13): 4-year follow-up from a multicentre, open-label, randomised, phase 3 trial. Lancet Oncol 25(6):744\u0026ndash;759\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Mantle cell lymphoma, acute myeloid leukemia, zanubrutinib, TP53 mutation, clonal evolution, therapy-related myeloid neoplasm","lastPublishedDoi":"10.21203/rs.3.rs-8897690/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8897690/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e \u003cspan type=\"SmallCaps\" class=\"SmallCaps\" name=\"Emphasis\"\u003eSecondary myeloid neoplasms have been reported with ibrutinib and acalabrutinib but not with zanubrutinib. We present a female patient in her late 80s with TP53-deleted pleomorphic mantle cell lymphoma who achieved metabolic complete remission with zanubrutinib-rituximab but remained MRD-positive for TP53. Eighteen months later, she developed AML harboring TP53, NPM1, FLT3-TKD, and DNMT3A mutations. The shared TP53 mutation and persistent MRD suggest clonal evolution from a common hematopoietic progenitor rather than drug-induced leukemogenesis, though zanubrutinib's potential role in facilitating this evolution through immunosuppression and clonal selection cannot be excluded.\u003c/span\u003e \u003c/p\u003e","manuscriptTitle":"Secondary Acute Myeloid Leukemia with Shared TP53 Mutation Following Zanubrutinib-Rituximab for High-Risk Mantle Cell Lymphoma: Clonal Evolution or Treatment Effect?","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-25 07:04:12","doi":"10.21203/rs.3.rs-8897690/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9ef09e99-f087-41c2-bdaa-c3ed027b9031","owner":[],"postedDate":"February 25th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-21T04:10:02+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-25 07:04:12","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8897690","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8897690","identity":"rs-8897690","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}