Severe Myelosuppression Research Articles

Incidence of thiopurine induced severe myelosuppression in a nationwide cohort of inflammatory bowel disease patients.

There is paucity of data on the incidence of severe thiopurine (TP)-induced myelosuppression (TIM) among inflammatory bowel disease (IBD) patients. Utilizing the Veterans Affairs Healthcare system we identified IBD patients with normal pre-treatment thiopurine S-methyltransferase(TPMT) levels who received TPs for 6 months and developed severe TIM. Among 73,392 IBD patients, 14,760 had received TPs, and 2823 had a normal TPMT level. The incidence rate of severe TIM was 1.25 per 1000 patient-years. The incidence of severe TIM was very low, calling into question the necessity of frequent long-term CBC monitoring among IBD patients on TPs.

Budget impact analysis of TPMT and NUDT15 pharmacogenomic testing for 6-mercaptopurine in pediatric acute lymphoblastic leukemia patients.

Pharmacogenomic testing identifies gene polymorphisms impacting drug metabolism, aiding in optimizing treatment efficacy and minimizing toxicity, thus potentially reducing healthcare utilization. 6-Mercaptopurine metabolism is affected by thiopurine methyltransferase (TPMT) and nudix hydrolase 15 (NUDT15) polymorphisms. We sought to estimate the budget impact of preemptive pharmacogenomic testing for these genes in pediatric acute lymphoblastic leukemia (ALL) patients from an institutional perspective. A Markov model was constructed to model the first cycle of the maintenance phase of chemotherapy for pediatric ALL patients transitioning between one of three health states: stable, moderately myelosuppressed, and severely myelosuppressed over 16 weeks, with each health state's associated costs derived from the literature. The patient's likelihood to experience moderate or severe myelosuppression based on metabolism phenotype was calculated from the literature and applied on a weekly basis, and the marginal budget impact of preemptive pharmacogenomic testing vs. no pharmacogenomic testing was calculated. One-way sensitivity analysis was conducted to assess parameter influence on results. Preemptive pharmacogenomic testing of TPMT and NUDT15 provided savings of up to $26 028 per patient during the maintenance phase. In the sensitivity analysis, the cost of outpatient management of moderate myelosuppression had the greatest impact on the budget, resulting in cost savings ranging from $8592 to $30 129 when the minimum and maximum costs of management were used in the model. Preemptive pharmacogenomic testing for TPMT and NUDT15 polymorphisms before initiation of maintenance therapy for pediatric ALL patients yielded considerable cost savings.

Severe myelosuppression causing pancytopenia in a patient with Crohn’s disease: an uncommon complication of azathioprine

Azathioprine, is widely used to treat many diseases as a steroid sparing drug, including inflammatory bowel disease. Whilst it can commonly result in leucopenia, in rare instances, it can cause severe myelosuppression and pancytopenia. We present a patient with Crohn’s disease, who developed severe myelosuppression resulting in pancytopenia and neutropenic sepsis secondary to azathioprine use.

Development of Fournier's gangrene after chemotherapy for the recurrence of testicular cancer despite the absence of anorectal lesions: A case report.

Fournier's gangrene usually occurs when a specific bacterium intrudes into soft tissue, causing a wound or tumor. We encountered a patient with Fournier's gangrene due to severe myelosuppression after chemotherapy, despite the absence of an initial lesion on the anus and rectum. A 54-year-old man with a left testicular cancer recurrence had undergone chemotherapy. He had asymptomatic hepatitis and high hepatitis B virus DNA levels, which were normalized by administering tenofovir alafenamide fumarate. Twelve days after the start of chemotherapy, he complained of severe pain around the anus. The following day, he went into septic shock. Visual inspection showed dark purple skin discoloration on the left side of the anus. Laboratory data revealed severe neutropenia. Computed tomography showed a high density of soft tissue on the left side of the anus and gas bubbles in the left femoral ring. We diagnosed the patient with Fournier's gangrene due to a severe immunosuppressive state resulting from chemotherapy. We emergently removed necrotic tissue to the fullest extent possible. However, because the patient was in severe sepsis status, careful management in the intensive care unit was required for 32 days. After the first emergency operation, we performed several additional excisions. Finally, 391 days after the initial surgery, the patient was discharged from our hospital. The tumor has not recurred, and he is under outpatient observation in the urology department. Fournier's gangrene should be considered in patients who are in a severe myelosuppressive state due to chemotherapy, have normal hepatitis B virus DNA levels but high hepatitis B surface antigen after tenofovir administration, complain of severe pain in the perianal area, and have a dark purple skin discoloration around the anus, despite having no initial anorectal lesions.

Effectiveness and safety of primary prophylaxis with G-CSF for patients with Ewing sarcomas: a systematic review for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology.

Multidrug chemotherapy for Ewing sarcoma can lead to severe myelosuppression. We proposed two clinical questions (CQ): CQ #1, "Does primary prophylaxis with G-CSF benefit chemotherapy for Ewing sarcoma?" and CQ #2, "Does G-CSF-based intensified chemotherapy improve Ewing sarcoma treatment outcomes?". A comprehensive literature search was conducted in PubMed, Cochrane Library, and Ichushi web databases, including English and Japanese articles published from 1990 to 2019. Two reviewers assessed the extracted papers and analyzed overall survival (OS), febrile neutropenia (FN) incidence, infection-related mortality, quality of life (QOL), and pain. Twenty-five English and five Japanese articles were identified for CQ #1. After screening, a cohort study of vincristine, ifosfamide, doxorubicin, and etoposide chemotherapy with 851 patients was selected. Incidence of FN was 60.8% with G-CSF and 65.8% without; statistical tests were not conducted. Data on OS, infection-related mortality, QOL, or pain was unavailable. Consequently, CQ #1 was redefined as a future research question. As for CQ #2, we found two English and five Japanese papers, of which one high-quality randomized controlled trial on G-CSF use in intensified chemotherapy was included. This trial showed trends toward lower mortality and a significant increase in event-free survival for 2-week interval regimen with the G-CSF primary prophylactic use compared with 3-week interval. This review indicated that G-CSF's efficacy as primary prophylaxis in Ewing sarcoma, except in children, is uncertain despite its common use. This review tentatively endorses intensified chemotherapy with G-CSF primary prophylaxis for Ewing sarcoma.

Primary prophylaxis with G-CSF for patients with non-round cell soft tissue sarcomas: a systematic review for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology.

Granulocyte colony-stimulating factor (G-CSF) is an essential supportive agent for chemotherapy-induced severe myelosuppression. We proposed two clinical questions (CQ): CQ #1, "Does primary prophylaxis with G-CSF benefit chemotherapy for non-round cell soft tissue sarcoma (NRC-STS)?" and CQ #2, "Does G-CSF-based intensified chemotherapy improve NRC-STS treatment outcomes?" for the Clinical Practice Guidelines for the Use of G-CSF 2022 of the Japan Society of Clinical Oncology. A literature search was performed on the primary prophylactic use of G-CSF for NRC-STSs. Two reviewers assessed the extracted papers and analyzed overall survival, incidence of febrile neutropenia, infection-related mortality, quality of life, and pain. Eighty-one and 154 articles were extracted from the literature search for CQs #1 and #2, respectively. After the first and second screening, one and two articles were included in the final evaluation, respectively. Only some studies have addressed these two clinical questions through a literature review. The clinical questions were converted to future research questions because of insufficient available data. The statements were proposed: "The benefit of primary G-CSF prophylaxis is not clear in NRC-STS" and "The benefit of intensified chemotherapy with primary G-CSF prophylaxis is not clear in NRC-STSs." G-CSF is often administered as primary prophylaxis when chemotherapy with severe myelosuppression is administered. However, its effectiveness and safety are yet to be scientifically proven.

Clinical features and treatment outcomes of liver involvement in paediatric Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is the most common histiocytic disorder in children, and liver involvement in LCH is rare. This retrospective study reported the clinical features and prognosis of patients with hepatic LCH. Liver involvement was defined by histopathological findings, liver dysfunction or abnormalities, or ultrasound imaging. A total of 130 patients (14.5%) with hepatic LCH out of 899 in the LCH population were enrolled. Patients with liver involvement had greater frequencies of skin, lung, hearing system, and haematologic system involvement, and hemophagocytic lymphohistiocytosis (P<0.001, 0.001, 0.002, 0.009, and <0.001, respectively). Overall survival and progression-free survival were lower in LCH patients with liver involvement than in those without liver involvement (P<0.001 and <0.001). In patients with liver involvement, the overall survival (OS) and progression-free survival (PFS) rates were lower in patients with cholangitis than in those without cholangitis (P<0.020 and 0.030). For the treatment response, the response rate of hepatic LCH patients to initial first-line therapy (n=89) was 22.5%. However, there was no significant difference in the response rate or recurrence rate between patients who shifted from first-line treatment to second-line treatment (n=29) or to targeted therapy (n=13) (P=0.453 and 1.000). The response rate of hepatic LCH patients who received initial second-line therapy (n=13) was 38.5%. Two of these patients subsequently experienced bone recurrence. The response rate of hepatic LCH patients who received initial targeted therapy (n=16) was 75.0%. Three patients subsequently experienced recurrence, including 2 in the bone and 1 in the liver and skin. A total of 39.3% of patients who received second-line treatment had severe myelosuppression (grade III-IV), and 50.8% had varying degrees of gastrointestinal events, whereas there was no severe toxicity in patients who received first-line treatment and targeted therapy. Four patients underwent liver transplantation because of liver cirrhosis. The patients’ liver disease improved within a follow-up period of 18-79 months. This study demonstrated that LCH with liver involvement, especially cholangitis, indicates a poor prognosis. Targeted therapy provides a good treatment response and less toxicity. However, it may relapse after withdrawal. Liver transplantation is still a reliable salvage option for patients with end-stage liver disease.

Antibody-Drug Conjugate Sacituzumab Govitecan Enables a Sequential TOP1/PARP Inhibitor Therapy Strategy in Patients with Breast Cancer.

The antibody-drug conjugate (ADC) sacituzumab govitecan (SG) comprises the topoisomerase 1 (TOP1) inhibitor (TOP1i) SN-38, coupled to a monoclonal antibody targeting trophoblast cell surface antigen 2 (TROP-2). Poly(ADP-ribose) polymerase (PARP) inhibition may synergize with TOP1i and SG, but previous studies combining systemic PARP and TOP1 inhibitors failed due to dose-limiting myelosuppression. Here, we assess the proof-of-mechanism and clinical feasibility for SG and talazoparib (TZP) employing an innovative sequential dosing schedule. In vitro models tested pharmacodynamic endpoints, and in a phase 1b clinical trial (NCT04039230), 30 patients with metastatic triple-negative breast cancer (mTNBC) received SG and TZP in a concurrent (N = 7) or sequential (N = 23) schedule. Outcome measures included safety, tolerability, preliminary efficacy, and establishment of a recommended phase 2 dose. We hypothesized that tumor-selective delivery of TOP1i via SG would reduce nontumor toxicity and create a temporal window, enabling sequential dosing of SG and PARP inhibition. In vitro, sequential SG followed by TZP delayed TOP1 cleavage complex clearance, increased DNA damage, and promoted apoptosis. In the clinical trial, sequential SG/TZP successfully met primary objectives and demonstrated median progression-free survival (PFS) of 7.6 months without dose-limiting toxicities (DLT), while concurrent dosing yielded 2.3 months PFS and multiple DLTs including severe myelosuppression. While SG dosed concurrently with TZP is not tolerated clinically due to an insufficient therapeutic window, sequential dosing of SG followed by TZP proved a viable strategy. These findings support further clinical development of the combination and suggest that ADC-based therapy may facilitate novel, mechanism-based dosing strategies.

OP11 Exploring the potential clinical utility of NUDT15 pharmacogenetic testing in clinical practice: a ‘focused reverse phenotyping’ study in the UK IBD Bioresource

Abstract Background In a previous study we recruited patients with inflammatory bowel disease (IBD) and a history of thiopurine induced myelosuppression (TIM) and identified associated variants in NUDT15. This widely used phenotype-first approach, is limited by ascertainment and recall bias, which impacts understanding of penetrance, expressivity, and variant pathogenicity that are key to clinical implementation. The United Kingdom (UK) National Institute for Health Research (NIHR) IBD Bioresource allows investigators to select large numbers of subjects based on genomic variants of interest, rather than phenotypes, to overcome these biases. Using this ‘focused reverse phenotyping’ approach we sought to investigate the cumulative 6-month risk of myelosuppression in patients with NUDT15 variants. Methods Cases and controls were identified from whole exome sequencing data. Cases included all participants with a loss of function NUDT15 variant (*2, *3, *4, *5, *6 and *9). Control subjects were selected based on wild-type carriage of NUDT15 and TPMT, matched for ethnicity. Our primary outcome measure was time to TIM. Myelosuppression was defined as a white cell count (WCC) &amp;lt;3.5x109/L or a neutrophil count &amp;lt;2.0x109/L that occurred within six months of achieving the maximum thiopurine dose, or in the absence of blood test results, a decision to reduce the dose of or withdraw the thiopurine due to myelosuppression. Severe myelosuppression was defined as a WCC &amp;lt;2.5x109/L or neutrophil count &amp;lt;1.0x109/L and a decision to either reduce the dose of or stop the thiopurine. Results We screened 23,082 patients recruited to the UK NIHR IBD bioresource with whole exome sequence data and identified 451 patients with a loss of function NUDT15 variant. We matched, based on ethnicity, these patients to 916 controls. Overall, 271/21,136 (1.3%) Caucasians and 127/1,089 (11.7%) South Asian carried an NUDT15 variant allele. 239/451 (60%) cases had a history of thiopurine exposure. The median weight-adjusted maximum thiopurine dose amongst cases and controls was 1.78 and 1.79 mg/kg/day, respectively. The time to myelosuppression was shorter in patients with NUDT15 variants as shown in Figure 1. The risk of myelosuppression, severe myelosuppression, and hospitalisation was also higher in patients with NUDT15 variants as shown in table 1. Conclusion In this reverse phenotyping study, the time to myelosuppression was significantly shorter in patients who carried a loss of function NUDT15 variant. The overall risk of myelosuppression was lower than previously observed in phenotype-first studies. Prior to implementation further analysis of the cost-effectiveness of NUDT15 testing is required.

Total skin radiation therapy with low-dose helical tomotherapy for a patient with mycosis fungoides

ABSTRACT Total body skin irradiation with electron beams has been used for patients with mycosis fungoides (MF). Recently, helical tomotherapy was considered available for total body irradiation, although severe myelosuppression was frequently observed as an adverse event. We report the first case of low-dose helical tomotherapy in a patient with MF. An 87-year-old Asian male with an 18-year medical history of MF was referred to our department due to a rapidly growing skin lesion during systemic therapy. He decided to undergo low-dose total skin radiotherapy with helical tomotherapy. The total skin was treated by dividing into three parts (trunk, head, and lower extremities). Each part was treated with helical radiotherapy consisting of 10 Gy in 5 fractions, with the administration of 5 fractions per week. Once the skin lesion clearly disappeared after total skin radiotherapy, recurrence was detected in the lower abdominal wall in the radiation-treated field. Insufficient doses of radiation therapy cause early relapse. There is still no optimized dose for total skin irradiation in helical tomotherapy. Further radiation therapy dose trials are required to optimize the treatment schedule.

Enhancer mutations modulate the severity of chemotherapy-induced myelosuppression.

Non-small cell lung cancer is often diagnosed at advanced stages, and many patients are still treated with classical chemotherapy. The unselective nature of chemotherapy often results in severe myelosuppression. Previous studies showed that protein-coding mutations could not fully explain the predisposition to myelosuppression. Here, we investigate the possible role of enhancer mutations in myelosuppression susceptibility. We produced transcriptome and promoter-interaction maps (using HiCap) of three blood stem-like cell lines treated with carboplatin or gemcitabine. Taking advantage of publicly available enhancer datasets, we validated HiCap results in silico and in living cells using epigenetic CRISPR technology. We also developed a network approach for interactome analysis and detection of differentially interacting genes. Differential interaction analysis provided additional information on relevant genes and pathways for myelosuppression compared with differential gene expression analysis at the bulk level. Moreover, we showed that enhancers of differentially interacting genes are highly enriched for variants associated with differing levels of myelosuppression. Altogether, our work represents a prominent example of integrative transcriptome and gene regulatory datasets analysis for the functional annotation of noncoding mutations.

An odd case of immune-mediated necrotizing myopathy, complicated with sagittal, transverse and sigmoid sinus thrombosis

INTRODUCTION: Immune-mediated necrotizing myopathy (IMNM) is a rare variant of immune-mediated inflammatory myopathy (IMIM) that exhibits a severe prognosis and is unresponsive to conventional treatment. (1,2)Notably, the incidence of immune-mediated inflammatory myopathies (IMIMs) is low, estimated at 1.16 to 19/million/year and only 3-6% of IMIMs are diagnosed as IMNM. (1,3–5). Systemic inflammation has been found to play a crucial role in promoting the onset of cerebral venous thrombosis. (6,7) MATERIAL AND METHODS: We present the case of a 46-years-old Chinese woman, without any known prior pathology, who was referred to the Rheumatology Department for symmetrical, proximal muscle weakness of the limbs, dysphagia for solid food, and weight loss (5 kg within 2 months). The pathologic clinical examination revealed itchy erythematous plaques on the posterior thoracolumbar region and signs of muscle weakness. Laboratory workup showed significant inflammatory syndrome, severe muscle and hepatic cytolysis syndrome, and positivity for thyroid-specific autoantibodies but with normal thyroid function, positivity for antinuclear antibodies (more precisely: SS-A, Ro-52, SS-B), and myositis antibodies (SRP, Ro-52, SAE1, PM-Scl, MDA5). The CT scan of the thoracic, abdominal, and pelvis showed fibrosis of the lungs, hepatic hypertrophy, and an enlarged uterus, further diagnosed by transvaginal ultrasound as adenomyosis. The positive diagnosis is immune-mediated necrotizing myopathy. Differential diagnoses included dermatomyositis, toxic/infectious myositis, hypothyroidism, and neuro-muscular diseases (5,8). The initial treatment was made with glucocorticoids (pulse therapy followed by oral therapy) and immunosuppressants (Mycophenolate Mofetil – stopped because of severe dyspepsia and myelosuppression). After five days of pulse therapy, the patient developed muscle weakness and paresthesia on the left side of the body, and the cerebral CT scan revealed sagittal, transverse, and sigmoid sinus thrombosis. Thrombophilia screening uncovered the positivity of the lupus anticoagulant. (9) RESULTS: The patient was treated with anticoagulants (low molecular weight heparin, and afterward Vitamin K antagonist), low doses of oral glucocorticoids, and immunosuppressant (Methotrexate), without any other adverse event. CONCLUSION: In the presence of the lupus anticoagulant, even though the antiphospholipid syndrome is not confirmed, the only anticoagulant therapy that has proven its efficacy is the Vitamin K antagonist. Immune inflammatory myopathies, like IMNMs, create a significant inflammatory status that leads to hypercoagulability and endothelial injury, which exposes collagen and tissue factors, promoting further platelet aggregation, and can even lead to cerebral thrombosis. (2,6)

Outcomes in Acute Lymphoid Leukemia Patients with Incomplete Hyper-CVAD Cycles

Introduction: Hyper-CVAD (hyperfractionated cyclophosphamide, vincristine, doxorubicin and dexamethasone) is a commonly used regimen in acute lymphoblastic leukemia (ALL) for a total of 4 A/B intensive courses. This regimen is often limited due to multiple complications including organ dysfunction and medication toxicities along with high rates of relapse or disease progression. Prior studies have indicated five-year overall survival (OS) of 39% with severe prolonged myelosuppression being a common complication. In one study 6% of patients died during induction therapy. Here we provide clinical outcomes of non-transplanted patients with ALL receiving hyper-CVAD regimen in our tertiary referral center. We assessed overall survival, mortality rates, and complications during induction therapy with hyper-CVAD in our cohort of adult patients. Methods: We conducted a comprehensive, retrospective study at our center, evaluating outcomes of non-transplant eligible ALL patients treated from February 2003 to October 2022. We excluded patients without all available diagnostic information, and those who underwent allogeneic stem cell transplantation (SCT). We classified the patient based on their BCR - ABL1 gene status. Groups were subcategorized by highest cycle of Hyper-CVAD completion, with reason for cessation (medication toxicity/organ dysfunction, lost to follow up, progressive disease/relapse) elicited for those who did not complete all treatment cycles. Overall survival was analyzed using T-Test, ANOVA and Bartlett's test. Statistics are descriptive and our institutional review board approved this retrospective study. Results: We report outcomes of 43 ALL patients who did not undergo SCT. Median age at diagnosis was 52 years (range of 18-71 years). 33/43 (76.7%) patients received Hyper-CVAD regimen. 2/33 (6.1%) completed the entire course through 4B. 12 (36.3%) out of 33 patients received less than cycle 3b; 21/33 (63.6%) received at least cycle 3b. 2/6 (33.3%) completed up to cycle 1B, 2/11 (18.2%) completed up to cycle 2B, 13/25 (52%) completed up to cycle 3B, and 2/33 (6.1%) completed up to cycle 4B. 12/33 (36.4%) of patients were not able to complete more than cycle 3A due to organ dysfunction and intolerance, being lost to follow up, progressive disease or relapse, or participation in a trial. For the patients who received less than cycle 3b, the reasons for early discontinuation were: organ dysfunction 6/12 (50%), progressive disease or relapse 3/12 (25%), lost to follow up 2/12 (16.7%), or participation in a trial 1/12 (8.3%). Median overall survival (OS) for patients who received up to cycle 3A was 640 days compared to a median of 711 days for those who received at least cycle 3B. Median OS for patients who received up to cycle 3A in the Ph-negative group was 21.0 months and 23.1 months in the Ph-positive group. Median OS for patients who received at least 3B in the Ph-negative group was 20.9 months and 23.9 months in the Ph-positive group. Conclusion: Hyper-CVAD is the mainstay of ALL treatment. Induction chemotherapy in ALL is commonly associated with myelosuppression and documented infections (sepsis, pneumonia, port infection). Other significant side effects include neurotoxicity, liver and kidney failure. Induction chemotherapy in some patients was a limiting factor in completing therapy. We report the different reasons for terminating the treatment course to be: organ dysfunction or intolerance such as liver injury, neutropenic fever, septicemia, subarachnoid hemorrhage, renal failure, congestive heart failure, respiratory failure requiring intubation, port infection, cytokine release syndrome, and neurotoxicity. Median OS was longer in the Ph positive subgroup but the mortality rates for this subtype was not different between the patients who received up to cycle 3A verses those that received at least cycle 3B. In this study, our descriptive analysis did not show a clinically meaningful difference in survival in patients who did not finish the total induction course. A limitation of this study was not analyzing intrathecal prophylaxis as involvement of the central nervous system is a major clinical concern. Herein, we suggest a personalized approach in treating ALL patients considering infection risk, disease cytogenetic risk and depth of response to help adjusting the number of induction cycles based on the mentioned risk factors.

Impact of sex on treatment-related adverse effects and prognosis in nasopharyngeal carcinoma

BackgroundIn nasopharyngeal cancer (NPC), women have a lower incidence and mortality rate than men. Whether sex influences the prognosis of NPC patients remains debatable. We retrospectively examined the influence of sex on treatment-related side effects and prognosis in NPC.MethodsClinical data of 1,462 patients with NPC treated at the Southern Hospital of Southern Medical University from January 2004 to December 2015 were retrospectively examined. Statistical analysis was performed to assess differences in overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival(LRFS), and progression-free survival(PFS), as well as treatment-related adverse effects, including myelosuppression, gastrointestinal responses, and radiation pharyngitis and dermatitis, between men and women.ResultsWomen had better 5-year OS (81.5% vs. 87.1%, P = 0.032) and DMFS (76.2% vs. 83.9%, P = 0.004) than men. Analysis by age showed that the prognoses of premenopausal and menopausal women were better than those of men, whereas prognoses of postmenopausal women and men were not significantly different. Additionally, women had a better prognosis when stratified by treatment regimen. Furthermore, chemotherapy-related adverse effects were more severe in women than in men; however, the incidences of radiation laryngitis and dermatitis were not significantly different between the sexes. Logistic regression analysis revealed that the female sex was an independent risk factor for severe myelosuppression and gastrointestinal reactions.ConclusionsChemotherapy-related side effects are more severe but the overall prognosis is better in women with NPC than in men with NPC. Patients may benefit from a personalized treatment approach for NPC.Trial registrationThis study was approved by the Medical Ethics Committee of Nanfang Hospital of the Southern Medical University (NFEC-201,710-K3).

A NUDT15 Genetic Polymorphism Study in Adult Acute Leukemia Patients Integrating Pharmacogenomics and Clinical Practice: A Single Centre Experience from South India

Background: Severe myelosuppression secondary to thiopurines such as 6-Mercaptopurine (6-MP) in patients with acute leukemia undergoing maintenance therapy is frequently attributed to inherited genetic polymorphisms of Thiopurine Methyltransferase (TPMT); however, this is rare in the Asian population. Nucleoside diphosphate-linked moiety X-type motif 15 (NUDT15) is also responsible for encoding critical enzymes involved in 6-MP metabolism. We aimed to determine the frequency of genetic polymorphisms of NUDT15 in the South Indian population and the impact of the omission of 6-MP from the treatment protocol of these patients. Methods: We retrospectively reviewed 17 patients diagnosed with acute leukemia between May 2018 and May 2020 and analyzed the prevalence of NUDT15 genetic polymorphisms in these patients. The NUDT15 mutation study (NUDT15 415C&amp;gt;T) used allele-specific Real-Time PCR in peripheral blood. 6-Mercaptopurine (6-MP) was excluded from the treatment regimen of patients with NUDT15 genetic polymorphisms and the impact of its exclusion was also studied. Results: Among the 17 patients for whom we cared, 10 were diagnosed with B-cell Acute Lymphoblastic Leukemia (B-ALL), three with T-cell Acute Lymphoblastic Leukemia (T-ALL), one with Mixed Phenotype Acute Leukemia (MPAL), and one with Acute Promyelocytic Leukemia (APML). Treatment records could not be retrieved for 2 patients. NUDT15 mutations were present in six patients (36%) (see fig1), of whom two had homozygous (33%) polymorphisms and four had heterozygous (67%) polymorphisms. In the heterozygous group, 2 were Ph. (Philadelphia chromosome) negative B-ALL; one was treated with BFM and the other with hyper-CVAD, one Ph. positive B-ALL was treated with BFM + Ponatinib, and one High-risk APML was treated with the APML 4 protocol. In the homozygous group, treatment details could not be retrieved for one case, and the other patient had T-ALL, which was treated with hyper-CVAD. 6-MP was omitted from the treatment protocol for all NUDT15 mutation-positive patients, both homozygous and heterozygous. Of these patients, two developed grade 1 myelosuppression, one developed grade 2 myelosuppression, one developed dyselectrolytemia, and one patient did not develop any toxicity. The incidence of severe or grade 3 and 4 myelosuppression in NUDT15 polymorphisms receiving 6MP can be as high as 50% (Khaeso K et.al Front Pharmacol. 2021). In comparison, none of our patients developed grade 3 or 4 myelosuppression. Overall, treatment-related adverse events included grade 1-2 myelosuppression (n=6), grade 1-2 hepatotoxicity (n=1), deep vein thrombosis (n=2), and sepsis (n=2). Five of the 6 patients with NUDT15 mutations achieved complete remission (CR). Conclusion: The prevalence of NUDT15 polymorphisms was high in our study population. Based on a meta-analysis, the prevalence of NUDT15 in the South Indian population was 16.5%, and in patients with adverse effects, the pooled prevalence of NUDT15 polymorphisms was 49.51% (Anuraag Jena et.al. Expert Review of Clinical Pharmacology 2021). Based on our results, although limited by the small number of cases, we suggest that pre-emptive testing to detect these polymorphisms should be undertaken in all adult acute leukemia patients of South Indian origin, given their high prevalence in this population. The omission of 6-MP from treatment protocols can help prevent severe myelosuppression and treatment interruption or discontinuation, which in turn can improve treatment outcomes.

Analysis of the incidence, characteristics, and risk factors of complications during induction chemotherapy in children with high-risk neuroblastoma.

The presence of bone marrow involved and increased VMA were high-risk factors for infection, while NSE ≥ 200µg/L and LDH ≥ 1000 U/L were high-risk factors for hemorrhage. For those children who had experienced severe myelosuppression, the presence of bone marrow metastases, increased VMA, and LDH ≥ 1000 U/L were their risk factors. The presence of bone involvement was a high-risk factor for children to have non-myelosuppressive adverse effects. Complications that arise during induction chemotherapy could negatively impact the children's prognosis and overall quality of life. • The high-risk neuroblastoma (HR-NB) had a worse prognosis; there was a general international preference for high-intensity chemotherapeutic regimens in the induction phase to these children. • We analyzed the incidence and risk factors of complications during induction chemotherapy in children with HR-NB and tried to help clinicians predict such complications and adopt optimized therapeutic strategy.

A nomogram for predicting severe myelosuppression in small cell lung cancer patients following the first-line chemotherapy

This study aimed at establishing and validating a nomogram to predict the probability of severe myelosuppression in small cell lung cancer (SCLC) patients following the first-line chemotherapy. A total of 179 SCLC cases were screened as the training group and another 124 patients were used for the validation group. Predictors were determined by the smallest Akaike’s information criterion (AIC) in multivariate logistic regression analysis, leading to a new nomogram. The nomogram was validated in both training and validation groups and the predicting value was evaluated by area under the receiver operating characteristics (ROC) curve (AUC), calibration curve, and decision curve analysis (DCA). Age and tumor staging were extracted as predictors to establish a nomogram, which displayed the AUC values as 0.725 and 0.727 in the training and validation groups, respectively. This nomogram exhibited acceptable calibration curves in the two groups and its prediction added more net benefits than the treat-all scheme and treat-none scheme if the range of threshold probability in the DCA was between 15 and 60% in the training and validation groups. Therefore, the nomogram objectively and accurately predict the occurrence of severe myelosuppression in SCLC patients following the first-line chemotherapy.

Comparative analysis of hypomethylating agents as maintenance therapy after allogeneic hematopoietic stem cell transplantation for high-risk acute leukemia

We retrospectively analyzed the outcomes of 136 consecutive patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) at our center. Among them, 76 cases used hypomethylating agents (decitabine, n = 40; azacitidine, n = 36) as post-transplant maintenance therapy, whereas 60 contemporaneous patients did not adopt maintenance therapy. The 3-year incidences of relapse in two groups were 16.6% and 39.2% (p = .001). The 3-year OS and DFS in maintenance group were 84.0% and 78.6%, which were remarkably improved than in control group (60.0% and 58.0%) (p = .004, p = .011). Moreover, the 3-year relapse rates for patients receiving decitabine and azacitidine therapy were 8.5% and 25.0%, respectively (p = .019). Patients utilizing decitabine had more common possibility of grade 3–4 neutropenia than azacitidine (20.0% vs. 2.8%, p = .031). These results indicate that maintenance therapies using hypomethylating agents could reduce the risk of post-transplant recurrence, resulting into remarkable superior survival. Decitabine might lower relapse after allo-HSCT with somewhat more severe myelosuppression when being compared to azacitidine.

Cladribine and cytarabine in children refractory high risk multisystem Langerhans cell histiocytosis

There is no uniform regimen for refractory Langerhans cell histiocytosis (LCH). We retrospectively described patients with refractory multisystem and risk organ involvement LCH treated with the low-dose (Ara-c, 100 mg/m2/d × 5day; 2-CDA, 5 mg/m2/d × 5day) chemotherapy (LDC) and the intermediate-dose (Ara-c, 500 mg/m2/d × 5day; 2-CDA, 9 mg/m2/d × 5day) chemotherapy (IDC). 26 patients and 10 patients receiving the LDC and IDC regimen from January 2013 to December 2016 were included in the study. The overall response rate exhibited no significant difference between the LDC and IDC groups after four courses (76.9% vs 90%, P = 0.375) and eight courses (80.8% vs 100%, P = 0.135) of treatment. No statistical differences in the overall survival rate were observed between the two groups, but 5-year event-free survival rate of patients in the IDC group was higher than that in the LDC group at the median follow-up of 6.16 and 5.07 years (88.9% vs 52.9%, P = 0.033). The patients in the IDC group had more severe myelosuppression than those in the LDC group (grade 3/4 myelosuppression, 80% vs 19.2%, P = 0.001). The intermediate-dose regimen of 2CDA and Ara-c had a higher event-free survival rate and a similar overall survival rate compared with the low-dose regimen.

The c.415C>T polymorphism in NUDT15 is more frequent than the polymorphisms in TPMT in Chilean patients who use thiopurine drugs.

Azathioprine (AZA) and 6-mercaptopurine (6-MP) are drugs widely used in the treatment of autoimmune diseases. Among the enzymes involved in the metabolism of AZA and 6-MP are thiopurine methyltransferase (TPMT) and nudix hydrolase 15 (NUDT15). The existence of single nucleotide polymorphisms in the genes that code for these enzymes could decreased enzymatic activity AND lead to severe myelosuppression. The most relevant polymorphism is NUDT15*3 (rs116855232), where the replacement of cytosine for thymine at position 415, which in turn leads to a loss of enzymatic activity. In a previous study, it was identified that together the polymorphisms in the TPMT gene reach an allelic frequency of 3.81%. There is no information regarding the rs116855232 polymorphism in the NUDT15 gene, so this corresponds to the objective of this report. Blood samples from Chilean adult patients with indications for the use of AZA or 6-MP for different pathologies and who had undergone a TPMT gene polymorphism study were retrospectively analyzed. A total of 253 blood samples were analyzed. Of the 253 patients, 47 presented the c.415C>T polymorphism in the NUDT15 gene, 3 being homozygous and 44 heterozygous. Four of the heterozygous patients for NUDT15 also had the *3A variant in the TPMT gene, also heterozygous. The allelic frequency of the minor T allele found (9.88%) was very similar to that found in patients of Asian origin, and much higher than that reported for the European Caucasian or Latin American population.