RESUMO
OBJECTIVE: To document the results of outpatient hematopoietic stem cell transplantation (HSCT) from the peripheral blood (PB) of sibling donors without anti-thymocyte globulin (ATG) in the conditioning regimen. MATERIAL AND METHODS: Patients from a low-income population with severe AA who received a PB, unmanipulated sibling HLA-identical HSCT between 2000 and 2020 at a single institution were studied. Survival was the primary outcome. RESULTS: Forty-one transplants were performed. Time between diagnosis and transplant was five months (1-104). Median age was 37 (range, 4-61) years; 25 (61 %) recipients were males and 32 (78 %) had treatment failure, 9 (22 %) have not received treatment. ATG was administered in 5 (12.2 %) cases; the graft source was PB in 38 (92.7 %) transplants. Twenty-six (63.4 %) transplants were carried out in the outpatient setting. Infections developed in 14 (34.1 %) patients. Primary graft failure (GF) occurred in 3 (7.3 %) patients. The 15-year OS was 81 %, EFS was 77.4 %. Patients with high pre-HSCT transfusion burden had lower OS (p = 0.035) and EFS (p = 0.026). Previous treatment failure and age were not associated with lower OS (p = 0.115, p = 0.069) or EFS (p = 0.088, p = 0.5, respectively). CONCLUSIONS: HLA-identical T-cell replete outpatient HSCT from the PB of sibling donors for AA patients using ATG-free conditioning offers excellent long-term survival.
RESUMO
BACKGROUND: HLA compatibility predicts allogeneic hematopoietic cell transplant (allo-HCT) and graft-versus-host disease (GvHD) outcomes. There is insufficient information regarding GvHD outcomes for outpatient HLA-identical and haploidentical-HCT employing reduced-intensity conditioning (RIC). RESEARCH DESIGN AND METHODS: We compare GvHD outcomes between donor types and report risk factors associated with GvHD. Stem cell source was T-cell replete peripheral blood. GvHD prophylaxis was post-transplant cyclophosphamide (PT-CY), mycophenolic acid, and calcineurin inhibitors for haploidentical (n = 107) and oral cyclosporine (CsA) plus methotrexate i.v. for HLA-identical (n = 89) recipients. RESULTS: One hundred and ninety-six HCT transplant patients were included. aGvHD and cGvHD frequency were similar between HCT types. aGvHD severity was comparable, but severe cGvHD was less frequent in the haploidentical group (p = .011). One-hundred-day cumulative incidence (CI) of aGvHD for haploidentical and HLA-identical was 31% and 33% (p = .84); 2-year CI of cGvHD was 32% and 38% (p = .6), respectively. Haploidentical recipients had less steroid-refractory cGvHD (p = .043). Patients with cGvHD had less 2-year relapse (p = .003); both aGvHD and cGvHD conferred higher OS (p = .010 and p = .001), respectively. Male sex was protective for steroid-refractory cGvHD (p = .028). CONCLUSIONS: Acute and chronic GvHD rates were comparable between HLA-identical and haploidentical transplant groups. cGvHD severity was lower in the haploidentical group.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Masculino , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Pacientes Ambulatoriais , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/epidemiologia , Ciclofosfamida/uso terapêutico , Esteroides , Condicionamento Pré-Transplante/efeitos adversosRESUMO
ABSTRACT Introduction: Pre-apheresis peripheral blood CD34+ cell count (PBCD34+) is the most important predictor of good cell mobilization before hematopoietic stem cell transplantation, albeit flow cytometry is not always immediately available. Identification of surrogate markers can be useful. The CD34+ cells proliferate after mobilization, resulting in elevated lactate dehydrogenase (LDH) activity and correlating with the PBCD34+ count. Objective: To determine the LDH cut-off value at which adequate CD34+ cell mobilization is achieved and its diagnostic yield. Materials and methods: A total of 103 patients who received an autologous stem cell transplantation (ASCT) between January 2015 and January 2020 were included. Demographic and laboratory characteristics were obtained, including complete blood count, pre-apheresis PBCD34+ and LDH levels. Receiver operating characteristic (ROC) curves were performed to identify the optimal serum LDH activity cut-off points for ≥ 2 and ≥ 4 × 106 cells/kg post-mobilization CD34+ count and their diagnostic yield. Results: A post-mobilization serum LDH cut-off value of 462 U/L yielded a sensitivity (Se) = 86.8% (positive predictive value [PPV] = 72.7%), a pre- and post-mobilization serum LDH difference cut-off value of 387 U/L, an Se = 45.7% (PPV = 97%) and an LDH ratio of 2.46, with an Se = 47.1% (PPV = 97%) for an optimal mobilization count (CD34+ ≥ 4 × 106). Conclusion: The LDH measurement represents a fast and affordable way to predict PBCD34+ mobilization in cases where flow cytometry is not immediately available. According to the LDH diagnostic yield, it could be used as a surrogate marker in transplant centers, supporting the CD34+ count, which remains the gold standard.
RESUMO
BACKGROUND: While second-generation tyrosine kinase inhibitors (TKI) revolutionized treatment for patients with chronic myeloid leukemia (CML) who developed a suboptimal response to imatinib, many patients in developing countries are fixed to the latter due to socioeconomic barriers. Despite this scenario, scarce information is available to evaluate the clinical prognosis of these patients. METHODS: We conducted a retrospective cohort analysis to compare the overall mortality of patients with CML who developed a suboptimal response to a standard dose of imatinib and were treated with either high-dose imatinib or a second-generation TKI. We created a marginal structural model with inverse probability weighting and stabilized weights. Our primary outcome was overall survival (OS) at 150 months. Our secondary outcomes were disease-free survival (DFS) at 150 months and adverse events. RESULTS: The cohort included 148 patients, of which 32 received high-dose imatinib and 116 a second-generation TKI. No difference was found in the 150-month overall survival risk (RR: 95% CI 0.91, 0.55-1.95, P-value = .77; RD: -0.04, -0.3 to 0.21, P-value = .78) and disease-free survival (RR: 1.02, 95% CI 0.53-2.71, P-value = .96; RD: 0.01, -0.26 to 0.22, P-value = .96). There was also no difference in the incidence of adverse events in either group. CONCLUSION: Ideally, patients who develop a suboptimal response to imatinib should be switched to a second-generation TKI. If impossible, however, our findings suggest that patients treated with high-dose imatinib have a similar overall survival and disease-free survival prognosis to patients receiving a second-generation TKI.
Assuntos
Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva , Humanos , Hispânico ou Latino , Mesilato de Imatinib/administração & dosagem , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/mortalidade , Estudos Retrospectivos , Substituição de MedicamentosRESUMO
ABSTRACT Introduction: Acute myeloid leukemia (AML) is most commonly presented in older adults; however, it appears 10 years earlier in Latin American countries. Clinical evolution in older adults from this populations has not been characterized. We analyzed outcomes and survival predictors. Methods: Patients ≥ 55 years old diagnosed with AML at a hematology referral center from 2005 to 2020 receiving intensive chemotherapy (IC), low-dose cytarabine (LDAC) and best supportive care (BSC) were included. Survival analysis included the Kaplan-Meier and Cox models and the cumulative incidence of relapse (CIR). Results: Seventy-five adults were included and the overall survival (OS) was 4.87, 1.67 and 1.16 months, using IC, LDAC and BSC, respectively. The IC led to a higher OS (p < 0.001) and was a protective factor for early death, at a cost of more days spent hospitalized and more non-fatal treatment complications; non-significant differences were found between the LDAC and BSC. Eight (10.7%) patients underwent hematopoietic cell transplantation, with a higher OS (p = 0.013). Twenty (26.7%) patients achieved complete remission; 12 (60%) relapsed with a 6-month CIR of 57.9% in those < 70 years old vs. 86.5% in those ≥ 70 years old, p = 0.034. Multivariate analysis showed the white blood cell count (WBC) and IC had a significant impact on the patient survival, whereas chronological age and the Charlson comorbidity index (CCI) did not. Conclusion: AML in low-middle income countries demands a different approach; the IC improves survival, even with a high incidence of relapse, and should be offered as first-line treatment. Eligibility criteria should include WBC and a multidimensional evaluation. The age per se and the CCI should not be exclusion criteria to consider IC.
Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Leucemia Mieloide Aguda , Transplante de Células-Tronco Hematopoéticas , Citarabina , Tratamento FarmacológicoRESUMO
BACKGROUND: Despite the improvements in supportive care for allogeneic-hematopoietic cell transplantation (allo-HCT) recipients, infectious complications and infection-related mortality (IRM) continue to be a major issue for transplantation centers. METHODS: We herein report the infectious complications and IRM of 107 and 89 patients that underwent haploidentical (haplo-HCT) or HLA-identical HCT at a tertiary referral center during 2013-2020. Patients in the haplo-HCT group received post-transplant cyclophosphamide (PT-Cy), and all received reduced-intensity conditioning regimens. RESULTS: More haplo-HCT recipients presented severe infections in the pre-engraftment period (22.4% vs. 6.7%, p = 0.003). Viral (14.9% vs. 4.5%, p = 0.016) and fungal (12.1% vs. 1.1%, p = 0.003) etiologies were more common in this period in this group. The 100-day and 2-year cumulative incidence of IRM was 15% and 21% for the haplo-HCT and 5.6% and 17% for the HLA-identical group; no significant differences were observed between the groups. Fungal pathogens mainly contributed to IRM (33.3%). Infections were the most common cause of mortality (40/81, 49.4%). There were significant differences in donor/recipient CMV serostatus between transplant groups (0.002). CONCLUSIONS: No differences in IRM were observed based on allo-HCT type, with more haplo-HCT patients suffering from severe infections in the pre-engraftment period. Studies to assess future prevention, diagnostic, and treatment strategies to reduce IRM are warranted.
Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Humanos , Pacientes Ambulatoriais , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Ciclofosfamida , Doadores de Tecidos , Condicionamento Pré-Transplante , Estudos RetrospectivosRESUMO
INTRODUCTION: Pre-apheresis peripheral blood CD34+ cell count (PBCD34+) is the most important predictor of good cell mobilization before hematopoietic stem cell transplantation, albeit flow cytometry is not always immediately available. Identification of surrogate markers can be useful. The CD34+ cells proliferate after mobilization, resulting in elevated lactate dehydrogenase (LDH) activity and correlating with the PBCD34+ count. OBJECTIVE: To determine the LDH cut-off value at which adequate CD34+ cell mobilization is achieved and its diagnostic yield. MATERIALS AND METHODS: A total of 103 patients who received an autologous stem cell transplantation (ASCT) between January 2015 and January 2020 were included. Demographic and laboratory characteristics were obtained, including complete blood count, pre-apheresis PBCD34+ and LDH levels. Receiver operating characteristic (ROC) curves were performed to identify the optimal serum LDH activity cut-off points for ≥ 2 and ≥ 4 × 106 cells/kg post-mobilization CD34+ count and their diagnostic yield. RESULTS: A post-mobilization serum LDH cut-off value of 462 U/L yielded a sensitivity (Se) = 86.8% (positive predictive value [PPV] = 72.7%), a pre- and post-mobilization serum LDH difference cut-off value of 387 U/L, an Se = 45.7% (PPV = 97%) and an LDH ratio of 2.46, with an Se = 47.1% (PPV = 97%) for an optimal mobilization count (CD34+ ≥ 4 × 106). CONCLUSION: The LDH measurement represents a fast and affordable way to predict PBCD34+ mobilization in cases where flow cytometry is not immediately available. According to the LDH diagnostic yield, it could be used as a surrogate marker in transplant centers, supporting the CD34+ count, which remains the gold standard.
RESUMO
INTRODUCTION: Acute myeloid leukemia (AML) is most commonly presented in older adults; however, it appears 10 years earlier in Latin American countries. Clinical evolution in older adults from this populations has not been characterized. We analyzed outcomes and survival predictors. METHODS: Patients ≥ 55 years old diagnosed with AML at a hematology referral center from 2005 to 2020 receiving intensive chemotherapy (IC), low-dose cytarabine (LDAC) and best supportive care (BSC) were included. Survival analysis included the Kaplan-Meier and Cox models and the cumulative incidence of relapse (CIR). RESULTS: Seventy-five adults were included and the overall survival (OS) was 4.87, 1.67 and 1.16 months, using IC, LDAC and BSC, respectively. The IC led to a higher OS (p < 0.001) and was a protective factor for early death, at a cost of more days spent hospitalized and more non-fatal treatment complications; non-significant differences were found between the LDAC and BSC. Eight (10.7%) patients underwent hematopoietic cell transplantation, with a higher OS (p = 0.013). Twenty (26.7%) patients achieved complete remission; 12 (60%) relapsed with a 6-month CIR of 57.9% in those < 70 years old vs. 86.5% in those ≥ 70 years old, p = 0.034. Multivariate analysis showed the white blood cell count (WBC) and IC had a significant impact on the patient survival, whereas chronological age and the Charlson comorbidity index (CCI) did not. CONCLUSION: AML in low-middle income countries demands a different approach; the IC improves survival, even with a high incidence of relapse, and should be offered as first-line treatment. Eligibility criteria should include WBC and a multidimensional evaluation. The age per se and the CCI should not be exclusion criteria to consider IC.
RESUMO
BACKGROUND: B-cell acute lymphoblastic leukemia is frequent in Hispanic adolescents and young adults. Outcomes of implementation of pediatric-inspired regimens in low-and middle-income countries are not well known. METHODS: In this study we treated 94 adolescents and young adults with a local BFM regimen designed to be affordable with the use of native L-asparaginase and mitoxantrone administered in an outpatient fashion, and the of BCR/ABL and measurable residual disease (MRD) determined by high sensitivity flow cytometry for risk stratification. RESULTS: Induction mortality was 11%; 25% of patients had to abandon treatment or be transferred to another health system. Two-year overall (OS) and event free survival (EFS) were 61.5% and 49.8%, MRD-negative patients had a 24-month OS of 85.6% vs. 69.6% (p = .024) and EFS of 76% vs. 45.5% (p = .004). Patients older than 40 years and those who abandoned treatment had worse EFS. Overall drug costs in our regimen were 52% lower than those of CALGB10403. CONCLUSION: The treatment of AYAs with ALL with an outpatient focus was implemented successfully at a reduced cost. Genetic risk assessment, treatment abandonment and lack of access to novel therapies remain major barriers for improving outcomes.
Assuntos
Pacientes Ambulatoriais , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Humanos , Adulto Jovem , Intervalo Livre de Doença , Asparaginase/uso terapêutico , Neoplasia Residual/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Prognóstico , Resultado do TratamentoRESUMO
ABSTRACT Background: The date of acute lymphoblastic leukemia (ALL) diagnosis has been studied regarding potential etiologic roles with contrasting results and the issue remains controversial. The principal aim of this study was to analyze monthly variation of ALL diagnosis in a large homogenous Hispanic Latin American cohort over 15 years; its association with survival rates was also assessed. Methods: Clinical files and electronic records of 501 consecutive patients of all ages with ALL in northeastern Mexico over the years of 2004-2018 were scrutinized. Patients were divided into children <18 and adults >18 years. The Chi-square heterogeneity analysis was used to test for non-uniform variation. The Poisson regression analysis was used to fit sinusoidal (harmonic) models to the data, using the month of diagnosis as a covariate in a separate model. Results: During the study period 363 children (72.5%) and 138 adults (27.5%) (p < 0.001) were diagnosed with ALL. Heterogeneity across the months of diagnosis was confirmed (p = 0.019) and the Poisson regression analysis confirmed a significant monthly variation (p < 0.001) (95% CI, 3.024-3.745), a higher annual peak being observed in the month of March (p = 0.002), followed by a second peak in October (p = 0.026). The five-year OS for children was 68.2% (95% CI, 67.64-68.74) and for adults, 43.7% (95% CI, 42.67-44.71) (p < 0.001). No significant association between the month of diagnosis and OS was found (p = 0.789). Conclusion: The monthly variation of ALL diagnosis was documented; these results confirm the heterogeneous behavior of the disease and appear to be consistent with an interplay of environmental and biologic factors. Further studies are needed to examine putative candidate agents.
Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Leucemia-Linfoma Linfoblástico de Células PrecursorasRESUMO
Abstract Introduction Hemorrhagic cystitis (HC) is a common complication of haploidentical hematopoietic stem cell transplantation (haplo-HSCT), characterized by irritative symptoms of the urinary tract and a higher morbidity and mortality rate. The worldwide incidence is reported between 10% and 70%. The use of alkylating agents and BK viral infection are the most frequent etiologies. The aim of this study was to report the HC incidence in an outpatient haplo-HCST program with a reduced intensity-conditioning (RIC) regimen, cataloguing risk factors, complications and final outcomes. Methods The medical database of patients who received a haplo-HSCT between January 2012 and November 2017 was retrospectively analyzed. Demographic variables, general characteristics and HC incidence were included. Results One hundred and eleven patients were included, 30 (27%) of whom developed HC, most of them (70%) being grade II, with a 30-day (7-149) median time of post-transplant HC onset. The BK virus was detected in 71% of the urine samples analyzed. All HC patients responded to treatment, except two (6.6%), who died due to HC complications. Conclusions There was no difference in the HC incidence or severity, compared to that reported when performing haplo-HSCT in hospitalized patients, although the donor-recipient sex mismatch did relate to a higher HC incidence.
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Adulto Jovem , Vírus BK , Transplante de Células-Tronco Hematopoéticas , Cistite , Transplante Haploidêntico , Incidência , CiclofosfamidaRESUMO
BACKGROUND: Chronic inflammatory demyelinating polyneuropathy (CIDP), stiff-person syndrome (SPS), neuromyelitis optica spectrum disorders (NMOSD) and severe refractory myasthenia gravis (MG) are immune-mediated neurological diseases that severely affect patients' functionality and quality of life, with a considerable percentage undergoing relapse or not responding to conventional treatment options. Autologous hematopoietic stem cell transplantation (auto-HSCT) has emerged as a potential second-line treatment alternative. METHODS: We performed a literature review in PubMed/Medline, EMBASE, Web of Science and Cochrane Library from inception to September 2021 of reported cases and studies of CIDP, SPS, NMOSD and MG that underwent HSCT as a treatment option. RESULTS: A total of 173 patients who underwent HSCT were found, including 32 patients described in case reports and 60 in a phase 2 clinical trial with CIDP, 29 patients with SPS, 42 patients with NMOSD and 10 patients with refractory MG. Complete remission was documented in 68/92 patients with CIDP, 13/29 with SPS and 10/10 with MG. From the NMOSD cases, 24/42 were relapse-free at last follow-up, with 13/33 having negative anti-AQ4 antibodies after HSCT. From all the included studies, only 8/173 patients received an allogeneic HSCT, 4/8 after a failed auto-HSCT. All showed clinical improvement and disease remission. CONCLUSION: HSCT has the potential to induce long-term remission in patients with CIDP, NMOSD, SPS or MG with adequate safety and tolerability. Collaboration between centers is needed to implement larger, homogeneous prospective studies, focusing on immunological correlates of favorable long-term response.
Assuntos
Transplante de Células-Tronco Hematopoéticas , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica , Humanos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/terapia , Estudos Prospectivos , Qualidade de Vida , Transplante AutólogoRESUMO
Autologous hematopoietic stem cell transplantation (HSCT) has been recognized as treatment alternative for patients with severe, refractory autoimmune rheumatic diseases (ARDs). Usually, anti-thymocyte globulin (ATG)-containing conditioning regimens are employed; however, ATG is unavailable in some developing nations. We report our 15-year clinical experience autografting patients with ARDs with an ATG-free conditioning regimen and a brief assessment of patient-reported outcomes post-HSCT. All patients had active disease and were resistant to multiple lines of treatment. Event-free survival (EFS) was assessed using the Kaplan-Meier method. Eight patients underwent autologous HSCT. Diagnoses included juvenile idiopathic arthritis (n = 3), systemic lupus erythematosus (n = 2), systemic sclerosis (n = 2), and rheumatoid arthritis (n = 1). Median time from diagnosis to HSCT was 3 years (0.75-19). Hematological recovery was documented in all recipients, and 4 patients (50%) completed the procedure in a completely ambulatory setting. Five (62.5%) patients achieved complete response and 3 (37.5%) partial response. The median EFS was 7 months (95% CI, 4.97-9.02), and the 1-year EFS rate was 21.9% (95% CI, 18.25-25.76). Transplant-related mortality was 0%, and 1 recipient died 8 years post-HSCT due to chronic kidney disease. Six (75%) patients presented steroid dosage reduction post-HSCT, and 2 (25%) perceived improvement in functionality despite having relapsed. HSCT is a viable treatment alternative for selected patients with severe therapy-resistant ARDs, as an improvement in disease management and quality of life was documented. The need remains to elucidate the characteristics of the optimal HSCT candidate, as well as the adequate conditioning regimen when ATG is not available. Key Points ⢠Despite advances in the treatment of autoimmune rheumatic diseases, some patients remain refractory. In this context, autologous hematopoietic stem cell transplantation (HSCT) rises as a viable alternative. ⢠Of 8 HSCT recipients with autoimmune rheumatic diseases, 5 (62.5%) patients achieved complete response and 3 (37.5%) partial response, with a 1-year event-free survival of 21.9%. ⢠Transplant-related mortality was 0%, with 4 (50%) patients autografted in a completely outpatient setting. ⢠Even when relapse presented, patients reported an improvement in functionality and quality of life; also, a better response to DMARDs and a reduction in steroid dependency post-HSCT were documented.
Assuntos
Artrite Reumatoide , Doenças Autoimunes , Transplante de Células-Tronco Hematopoéticas , Soro Antilinfocitário , Artrite Reumatoide/tratamento farmacológico , Doenças Autoimunes/tratamento farmacológico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , América Latina , Qualidade de Vida , Transplante AutólogoRESUMO
INTRODUCTION: Hemorrhagic cystitis (HC) is a common complication of haploidentical hematopoietic stem cell transplantation (haplo-HSCT), characterized by irritative symptoms of the urinary tract and a higher morbidity and mortality rate. The worldwide incidence is reported between 10% and 70%. The use of alkylating agents and BK viral infection are the most frequent etiologies. The aim of this study was to report the HC incidence in an outpatient haplo-HCST program with a reduced intensity-conditioning (RIC) regimen, cataloguing risk factors, complications and final outcomes. METHODS: The medical database of patients who received a haplo-HSCT between January 2012 and November 2017 was retrospectively analyzed. Demographic variables, general characteristics and HC incidence were included. RESULTS: One hundred and eleven patients were included, 30 (27%) of whom developed HC, most of them (70%) being grade II, with a 30-day (7-149) median time of post-transplant HC onset. The BK virus was detected in 71% of the urine samples analyzed. All HC patients responded to treatment, except two (6.6%), who died due to HC complications. CONCLUSIONS: There was no difference in the HC incidence or severity, compared to that reported when performing haplo-HSCT in hospitalized patients, although the donor-recipient sex mismatch did relate to a higher HC incidence.
RESUMO
BACKGROUND: The date of acute lymphoblastic leukemia (ALL) diagnosis has been studied regarding potential etiologic roles with contrasting results and the issue remains controversial. The principal aim of this study was to analyze monthly variation of ALL diagnosis in a large homogenous Hispanic Latin American cohort over 15 years; its association with survival rates was also assessed. METHODS: Clinical files and electronic records of 501 consecutive patients of all ages with ALL in northeastern Mexico over the years of 2004-2018 were scrutinized. Patients were divided into children ≤18 and adults >18 years. The Chi-square heterogeneity analysis was used to test for non-uniform variation. The Poisson regression analysis was used to fit sinusoidal (harmonic) models to the data, using the month of diagnosis as a covariate in a separate model. RESULTS: During the study period 363 children (72.5%) and 138 adults (27.5%) (pâ¯<â¯0.001) were diagnosed with ALL. Heterogeneity across the months of diagnosis was confirmed (pâ¯=â¯0.019) and the Poisson regression analysis confirmed a significant monthly variation (pâ¯<â¯0.001) (95% CI, 3.024-3.745), a higher annual peak being observed in the month of March (pâ¯=â¯0.002), followed by a second peak in October (pâ¯=â¯0.026). The five-year OS for children was 68.2% (95% CI, 67.64-68.74) and for adults, 43.7% (95% CI, 42.67-44.71) (pâ¯<â¯0.001). No significant association between the month of diagnosis and OS was found (pâ¯=â¯0.789). CONCLUSION: The monthly variation of ALL diagnosis was documented; these results confirm the heterogeneous behavior of the disease and appear to be consistent with an interplay of environmental and biologic factors. Further studies are needed to examine putative candidate agents.