Bone marrow transplant: A two-decade single centre hematology experience.

Background: Bone Marrow Transplant (BMT) is a curative form of therapy for many hematological disorders in both the adult and pediatric patients. The availability of BMT in the AFMS at AHRR for the last 02 decades has been a game changer for the patients. Methods: We reviewed our BMT data since the inception of the program till Feb 2023. Results: Over 700 patients with more than 23 different types of hematological disorders have undergone this procedure 58%% patients underwent an Autologous BMT and 42% an allogenic BMT. Autologous BMT for Multiple Myeloma and Allogenic BMT for Aplastic Anemia and Acute Leukemias have been the most common indications. 73% patients were adults, and 27% patients were of the pediatric age group. The male: female ratio was 2:1. The spectrum of allogenic Hematopoietic Stem Cell Transplant (HSCT) has expanded from Matched Sibling Donor (MSD) transplants to Matched Unrelated Donor (MUD) Transplants and Haploidentical Donor Transplants. 93% of our Allogenic BMT patients underwent a MSD BMT, 1% MUD BMT and 06% Haploidentical BMT. Today no patient with a malignant hematological disorder requiring a BMT is denied the procedure due to the lack of an HLA donor due to the availability of haploidentical BMT. Conclusion: The evolution of a BMT program has a long learning curve and the expanded pool of eligible donors has led to a situation of "transplant for all". Haploidentical HSCT for nonmalignant hematological disorders is an unmet need. CART cell therapy and Cellular therapies need to be prioritized for future inclusion.

Successful T replete haploidentical HSCT with post-transplant cyclophosphamide in two patients with Wiskott-Aldrich syndrome.

We describe two young patients with Wiskott-Aldrich Syndrome (WAS) who were treated by T-replete hematopoietic stem cell transplantation (HSCT) from the HLA haploidentical father according to a modified Baltimore protocol. Whereas similar protocols have been successfully used in various malignant and non-malignant diseases, this is the first report for this particular disease. The data being presented pertains to the report about two successful haploidentical transplants with post transplant cyclophosphamide (PTCY) after busulfan-based conditioning.

18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Scan Findings in a Rare Case of Subcutaneous Panniculitis-Like T-Cell Lymphoma.

Skin lymphomas are less common and subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a fairly rare subtype of primary cutaneous lymphoma. Skin lymphomas involve subcutaneous adipose tissues with no involvement of lymph nodes. Diagnosis of these cases is generally a challenge to clinicians. These cases present with fever, weight loss, and local discomfort in the region of involvement of subcutaneous tissues and sometime with skin eczema and rashes. Positron emission tomography/computed tomography (PET/CT) scan can guide in determining the extent of involvement being whole-body imaging and can guide the site of biopsy and can help to prevent misdiagnosis. It also helps in correct and early diagnosis and successful treatment. We report a case of a young adult who presented with pyrexia of unknown origin in which PET/CT scan revealed mildly fluorodeoxyglucose-avid diffuse subcutaneous panniculitis involving the whole body, trunk, and extremities. Biopsy was taken from the most appropriate site according to the PET/CT scan report and reported as SPTCL.

Supplemental Pioglitazone to Patients of CML with Suboptimal TKI Response: A Pragmatic Pilot Study.

Tyrosine kinase inhibitors (TKIs) have improved outcomes of chronic myeloid leukemia (CML). However, 20-30% of patients require second-line TKIs following suboptimal response. The cost and adverse events limit their use in resource-constraint settings. We conducted a pilot study to ascertain the benefit of adding pioglitazone to TKIs with suboptimal response in real-world resource-constraint settings. In this pragmatic pilot study from 01 Jan 2017 to 31 July 2021, CML patients from a tertiary care center in North India with sub-optimal response to TKIs were additionally given pioglitazone after ruling out imatinib resistance mutation (n - 31). Pioglitazone was stopped if there was disease progression on follow-up, and second-line TKI was started. The data were analyzed with the intention-to-treat principle using JMP Ver.15.1.1. The median age of the study population was 54y (27-82), who were followed up for a median duration of 1023.5d (59-1117). Pioglitazone showed the benefit of one-log reduction in BCR-ABL in 89.7% of the study participants. 1y, 2y and 3y-PFS were 92.57%, 76.5%, and 68.3% respectively. During follow-up period, the disease progressed in 38.7%, of which two succumbed. No adverse events to Pioglitazone were documented. This study proved that adding Pioglitazone to the existing TKI regime in CML with sub-optimal response can benefit. The addition of Pioglitazone was well tolerated. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-022-01561-x.

Cancer in the Adolescent and Young Adults (AYA) and Children: A Comprehensive Analysis of the Epidemiology and Psychosocial Morbidity in the Indian Population.

Bhupesh GuleriaAims Adolescent and young adults (AYAs), children with cancer, and their guardians have unique psychosocial morbidities adversely effecting quality of life (QOL). This is measurable using patented tools. We analyzed epidemiological and clinicopathological patterns of solid organ cancers in this subgroup. We also assessed psychosocial morbidity and changes in QOL faced by them. Methods All patients aged 2 to 39 years, newly diagnosed with cancer from April 2017 to March 2019 were included. Clinical history, diagnosis, staging, treatment, outcomes, and follow-up were recorded. The National Comprehensive Cancer Network (NCCN) distress thermometer and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ C-30) were used to assess psychosocial morbidity of AYAs, children ≥ 12 years, and parents of children < 12 years. Pediatric Quality of Life Inventory (Peds QL) version 3.0 was used for children < 12 years. Data was analyzed using descriptive statistics. Results A total of 571 patients (512 AYAs, 59 children) were enrolled. Median age was 30 years with male predominance (58.1%). Most cases (98.6%) were absent from school or work. Carcinoma breast was the most common in females (29.3%) and non-Hodgkin lymphoma in males (12.6%). 91.06% had overall NCCN distress score ≥ 4. Also, 73.81 and 79.49% had "quite a bit" or "very much" responses on functional and symptom scales, respectively, in EORTC QLQ C-30 questionnaire. Peds QL version 3.0 revealed total score ranging from 276 to 523 for each patient. Conclusion AYAs and children with cancer are extremely vulnerable to psychological stress and morbidity. Use of well-established tools help in assessing their mental status and timely psychiatric referral can be initiated.

Immune Thrombocytopenia in a Kidney Transplant Recipient Treated with Romiplostim.

We present a case of immune thrombocytopenia following a living donor kidney transplant. Thrombocytopenia started two days after transplant and continued up to seven weeks after transplant, despite an extensive workup, treatment with steroids, intravenous immune globulin, and alterations in immunosuppression and other medications. In the absence of platelet transfusions, the patient's platelet count remained < 20,000/mm3. Platelet count responded to romiplistim (Nplate®, Amgen Inc.) within two weeks and has remained stable for twelve months after initiation of this agent. The patient's graft function has also been stable. This experience suggests romiplostim is safe and effective for persistent immune thrombocytopenia in kidney transplant recipients.

Safety and efficacy of splenectomy in immune thrombocytopenia.

BACKGROUND: Immune Thrombocytopenia (ITP) is characterized by low platelet counts. Splenectomy has been in practice for the treatment of ITP since the early 20th century. We aimed to analyze the data of ITP patients from our hospital who underwent splenectomy and further present the long-term outcome and safety profile in these patients. METHOD: This study was a single-center, registry based study conducted at a tertiary care hospital in Northern India. Patients aged 18 years or more, who underwent splenectomy after at least one line of therapy, were included in the study. The primary outcome was the overall response rate (ORR) at one month after splenectomy. Secondary outcomes were sustained response, relapse-free survival, factors affecting the ORR, and adverse events after splenectomy. RESULTS: Forty-five patients of ITP were included in the study. Thirty-six patients underwent splenectomy in the first half (2001-2010), of the study period. The median age of the patients was 38 (19-56) years. The median duration from diagnosis to splenectomy was 1.76 (0.47-2.58) years. The median number of therapy received before splenectomy was 3 (1-6). The overall response rate (ORR) post-splenectomy at day 30 was 89.2% with 61.8% complete response (CR). The ORR was 88.5% at 1-year, with 48.8% CR. The relapse-free survival (RFS) at 5-years was 57.38% (95% Confidence Interval 40.59-71.02%), There was no effect of duration of disease, age, gender, and prior therapy received, on the ORR at one-month. At one year, the platelet response was significantly better in patients who had a CR at one-month than patients who had a partial response at one month. The relapse-free survival was better in patients who achieved CR after 1-month of splenectomy. During the median follow-up of 5.02 (1 month-20 years) years, there were five cases of overwhelming post-splenectomy infection (OPSI). There was no recorded incidence of perioperative mortality, deep vein thrombosis, or mesenteric thrombosis. DISCUSSION: Despite the variation in outcome from different studies, splenectomy gives the best possible long-term treatment-free remission amongst all the available second-line agents. It is also, one of the most financially affordable therapies. Despite advantages, the number of ITP patients undergoing splenectomy has been on the decline and largely attributable to the newer and more effective second-line therapies. There is no pre-surgery variable predicting the ORR after splenectomy. CONCLUSION: Splenectomy in ITP offers a long-term sustained response at an economical cost.

The clinical profile, management, and outcome of febrile neutropenia in acute myeloid leukemia from resource constraint settings.

INTRODUCTION: Acute myeloid leukemia (AML) is the commonest leukemia in adults. Mortality in thew first 30-days ranges from 6% to 43%, while infections account for 30-66% of early deaths. We aim to present our experience of infections in newly-diagnosed AML. METHOD: This prospective, observational study, was undertaken at a tertiary care hospital in Northern India. Patients with confirmed AML (bone marrow morphology and flow cytometry) and who had developed febrile neutropenia (FN), were included. RESULT: A total of fifty-five patients were included in the study. The median age of the patients was 47.1 years (12-71) and 28 (50.9%) were males. Fever (33, 60%) was the commonest presentation at the time of diagnosis. One or more comorbid conditions were present in 20 patients (36.36%). Infection at presentation was detected in 17 patients (30.9%). The mean duration to develop febrile neutropenia since the start of therapy was 11.24 days. With each ten-thousand increase in white blood cell (WBC) count, the mean number of days of FN development decreased by 0.35 days (p = 0.029). Clinical and/or radiological localization was possible in 23 patients (41.81%). Thirty-four blood samples (34/242, 14.04%) from 26 patients (26/55, 47.3%) isolated one or more organisms. Gram negative bacilli (GNB) were isolated in 24 (70.58%) samples. Burkholderia cepacia (8/34, 23.52%) was the commonest organism. The number of days required to develop febrile neutropenia was inversely associated with overall survival (OS). However, when compared, there was no statistically significant difference in OS between patients developing fever on day-10 and day-25 (p = 0.063). Thirteen patients (23.63%) died during the study period. DISCUSSION: Low percentage of blood culture positivity and high incidence of MDR organisms are a matter of concern. Days to develop febrile neutropenia were inversely associated with overall survival (OS), emphasizing the importance of preventive measures against infections. CONCLUSION: Infections continues to be a major cause of morbidity and mortality among AML patients.

Cerebral Venous Thrombosis in Acute Lymphoblastic Leukemia with Severe COVID-19: a Case Report.

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has brought an unprecedented upheaval in our health-care systems. Amongst the many challenges posed by the disease, increased risk of thromboembolism has presented a distinct new front for increased mortality and morbidity. While there are multiple documented evidences for the same, the exact mechanism, knowledge of groups at-risk, and mitigation strategies are evolving. We present a case of a young individual who was diagnosed with acute lymphoblastic leukemia (ALL), was started on appropriate chemotherapy, and subsequently developed severe COVID-19 pneumonia. He was treated for COVID-19 pneumonia and recovered from the illness. However, his recovery from COVID-19 was further complicated by cortical venous sinus thrombosis (CVT). Contrast enhanced magnetic resonance imaging (CEMRI) brain and magnetic resonance venography (MRV) revealed the diagnosis of CVT with hemorrhagic parenchymal changes. He was managed with therapeutic anticoagulation and cerebral decongestants and was subsequently shifted to oral anticoagulant therapy. While the case was managed at a tertiary care setting, it opened up the question of identifying the high-risk groups and to formulate guidelines for extended thromboprophylaxis in these patients.

Ureteric Trauma following Stent Removal in Kidney Transplant Recipient: A Unique Case of Prolonged Morbidity.

A 52-year-old African-American male patient with end-stage renal disease due to hypertension underwent deceased donor kidney transplant procedure with no immediate complications. The postprocedure complications, interventions, and course were abstracted by chart review. The ureteric stent was removed with flexible cystoscopy on postoperative day (POD) 24. 24 hours later, the patient presented with abdominal pain and inability to urinate. An urgent ultrasound and noncontrast CT scan showed grade 4 hydronephrosis of the transplanted kidney. A percutaneous nephrostomy stent was placed for urinary diversion. A large ureteric hematoma filling the lumen of the mid to distal ureter was identified on the nephrostogram and was evacuated. A follow-up nephrostogram on POD 44 revealed a distal ureter stricture and persistent well-formed midureter filling defect. A repeat nephrostogram performed at POD 72 was done with stricture dilatation, internalization of stents, and removal of a percutaneous nephrostomy tube. The patient was maintained on antibiotics for UTI prophylaxis throughout the course.

Survival Outcomes of Newly Diagnosed Multiple Myeloma at a Tertiary Care Center in North India (IMAGe: 001A Study).

PURPOSE: The outcomes of patients with myeloma from developing countries are often lacking because of poor record maintenance. Publications from such settings are also limited because of the retrospective nature of the data collection. Information technology can bridge these gaps in developing countries with real-time data maintenance. We present the real-time survival data of the patients with myeloma from a tertiary care center in North India using one such indigenously built software. PATIENTS AND METHODS: These are real-time data of all patients with myeloma presenting to a tertiary care center from North India. The patient characteristics (demographics, baseline disease characteristics, risk stratification, and outcomes) were recorded contemporaneously. The survival of the study population was analyzed and grouped based on various disease characteristics at diagnosis. RESULTS: The median age of the study population (N = 696) was 65.9 (34.9-94.9) years with male predominance (65%). The median follow-up was 3.7 years (0-18.6 years) with the median overall survival (OS) not achieved. The OS of the study population at 1, 3, and 5 years was 94% (n = 558), 87.5% (n = 394), and 83.1% (n = 267), respectively. Most of the patients presented in advanced stages based on International Staging System (III:70%). On Kaplan-Meier analysis, the presence of weight loss (P = .01), renal dysfunction (P = .047), and anemia at diagnosis (P = .004) had a significant impact on survival. On Cox proportional model univariate analysis, the presence of renal dysfunction, anemia, and weight loss had the significant hazard ratio of 1.68 (1-2.82, P = .049), 3.18 (1.39-7.29, P = .0063), and 2.81 (1.22-6.42, P = .014), respectively, whereas on multivariate analysis of hypercalcemia, renal disease, anemia, and bone disease (CRAB) features, only anemia was found to have a significant hazard ratio of 2.56 (1.01-6.47, P = .046). CONCLUSION: The real-world data show OS comparable with the published western literature. Only anemia was found to have significant impact on survival. The use of such software can aid in better data-keeping in resource-constrained settings.

Profile of Hepatobiliary Dysfunction in Hematopoietic Stem Cell Transplant Recipients - An Indian Perspective.

BACKGROUND/AIMS: Hematopoietic stem cell transplantation (HSCT) is an established curative modality for various hematological malignancies and other diseases. Hepatobiliary dysfunction and subsequent sequelae constitute a common cause of morbidity and mortality in post-transplant scenario. However, data among Indian HSCT recipients is lacking. METHODS: One hundred and one HSCT recipients (37 prospective and 64 retrospective) were followed up for hepatobiliary dysfunction in the post-transplant period. The causes for hepatobiliary dysfunction were categorized as sinusoidal obstruction syndrome (SOS), formerly known as veno-occlusive disease (VOD); acute and chronic graft-versus- host disease (GVHD); drug-induced liver injury (DILI); viral infections and miscellaneous causes including bacterial, fungal and unknown causes based on clinical and laboratory evidence. RESULTS: Among the 101 transplants, 56.44% (n = 57) were allogenic transplants, and 43.56% (n = 44) were autologous transplants. Hepatobiliary dysfunction was observed among 71 (70.30%) patients in first 30 days and overall, among 78 (77.23%) patients. Incidence of hepatobiliary dysfunction was higher among allogenic transplant patients compared to autologous transplants (91.23% vs. 59.09%, p < 0.001). The most common cause of hepatobiliary dysfunction reported was Drug-induced liver injury (DILI). In most cases, however, hepatobiliary dysfunction was multifactorial. Sinusoidal obstruction syndrome (15.79%), acute liver GVHD (31.58%), chronic liver GVHD (33.33%) and viral infection/reactivation (26.32%) were reported only in allogenic transplant patients. 15 (14.85%) patients died of which 14 patients had hepatobiliary dysfunction, commonest cause being infections. CONCLUSION: Our study reported a higher incidence of hepatobiliary dysfunction among Indian population post HSCT and was associated with significant mortality. In majority of the cases, the cause is multifactorial and pose a diagnostic dilemma and challenges in therapy.

Disseminated Histoplasmosis Presenting as Weight Loss and Hypercalcemia in a Renal Transplant Patient With Prior History of Subtotal Parathyroidectomy.

Hypercalcemia and weight loss in a renal transplant patient especially with history of parathyroidectomy raises concern for an underlying malignancy, fungal infections or granulomatous disease. We present a case of 45-year-old male with history of subtotal parathyroidectomy presented with severe persistent hypercalcemia, acute kidney injury (AKI) and significant weight loss. An extensive workup revealed disseminated histoplasmosis. Hypercalcemia (which was refractory to initial medical management) and other symptoms resolved after a few weeks of initiating the antifungal treatment.

Reinfection or Reactivation of Coronavirus-19 in Patients with Hematologic Malignancies: Case Report Series.

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been relentless. We are into the 10th month of the pandemic, and we are still getting surprised every day. Although neutralizing antibodies are generated in response to coronavirus disease-19 (COVID-19), these antibodies do not appear to confer lifelong immunity, as lately there have been reports from various parts of the world of reinfection with the virus, starting from Hong Kong, Belgium, and the USA. The Indian Council of Medical Research (ICMR) has been on-record claiming three cases of reinfection in India. Herein, we report three patients of hematologic malignancy who most probably had reinfection with SARS-CoV-2, after complete documented recovery from first infection. All three patients were immunocompromised owing to their primary hematologic malignancy coupled with ongoing therapy, and the second infection was documented to be severe in all the three cases from the first episode.

Pembrolizumab-induced severe rejection and graft intolerance syndrome resulting in renal allograft nephrectomy.

INTRODUCTION: Pembrolizumab is a selective anti-programmed cell death protein-1 (PD-1) humanized monoclonal antibody that inhibits PD-1 activity by binding to the PD-1 receptor that is found on activated T-cells. The goal of the treatment is to allow the immune system to target and destroy cancer cells by preventing cancer cells from binding to PD-1 receptors, leading to decreased tumor growth. The activation of T-cells by pembrolizumab not only leads to the destruction of malignant cells but also attacks the donor alloantigens that are present in a renal transplant, resulting in graft rejection. CASE REPORT: We present a case of a 46-year-old African American female with history of renal transplant who was treated with pembrolizumab for stage IV B endometrial adenocarcinoma and experienced renal transplant rejection and severe graft intolerance syndrome.Management and outcome: Due to ongoing graft intolerance, a transplant nephrectomy was performed. Allograft pathology was consistent with non-viable kidney with tubulitis, interstitial fibrosis and necrosis consistent with transplant rejection without any evidence of malignancy. DISCUSSION: As emphasized in our case, there is a very high risk of graft rejection in patients who need to be placed on immunomodulators such as pembrolizumab, so the risk versus benefit needs to be assessed and discussed. Our case is unique because pembrolizumab not only caused graft rejection but also severe graft intolerance syndrome which led to transplant nephrectomy. Further guidelines are needed in renal transplant patients requiring PD-1 inhibitors to establish the ideal treatment plan of immunosuppression management and anti-cancer treatments.

Severe Intraoperative Anaphylaxis Related to Thymoglobulin during Living Donor Kidney Transplantation.

Anaphylaxis secondary to thymoglobulin (anti-thymocyte globulin) is a rare condition that can be life threatening. Thymoglobulin is a rabbit-derived T-cell depleting polyclonal immunoglobulin. It is commonly used for induction immunosuppression and/or for treatment of acute rejection in renal transplantation. We report a case of a living kidney transplant recipient who developed intraoperative anaphylactic shock secondary to thymoglobulin. The patient had a history of pet rabbit exposure. This case report highlights the importance of prompt identification and management of intraoperative anaphylaxis, which is key to a successful outcome. Induction immunosuppression selection based on patient characteristics is important. Communication between the anesthesia team and surgeons played a key role in stopping the donor surgery.

Risk Stratification in Multiple Myeloma in Indian Settings.

Multiple myeloma (MM) constitutes 10% of all hematological malignancies. The last one decade has seen a phenomenal progress in the therapeutic options available for the management. Although it still remains incurable, with the advent of newer therapies, the median survival in many risk groups is now around 10 years. Conventional karyotyping of bone marrow samples has a positivity rate of 20-30% at diagnosis in patients of Multiple Myeloma. However, array Comparative Genomic Hybridisation (aCGH) has revealed that almost all MM patients have cytogenetic abnormalities which may affect the pathophysiology, selection of therapy and outcomes of the disease. The progress in the field of exploring the genetic landscape of multiple myeloma with multiple tools like Fluorescent in-situ hybridization, aCGH, Next Generation Sequencing, Flow cytometry, etc., combined with the traditional risk stratification markers like albumin, ß2 microglobulin and LDH, is gradually leading towards a risk-adapted therapy. The recent R-ISS risk stratification has combined these two group of information to validate a prognostic score which is an improvement over the past tools like DSS and ISS. In view of the plethora of information available on the multitude of cytogenetic markers there is a tendency to evaluate for all of them at diagnosis, especially in research centers. This leads to a significant increase in the cost of therapy of Multiple Myeloma in day-to-day clinical practice and an increased out-of-pocket spending to the patient, especially in resource-limited settings like India. Also, there is a variable approach to pre-therapy cytogenetic evaluation and risk stratification at different Hematology centres in the country, often dictated by financial constraints and availability of specialized tests. This review discusses the risk stratification markers and tools available in MM in 2019 and how it can be adapted in the resource constraint settings so as to derive the maximum prognostic information from a minimal prognostic panel, as well as lead to standardization of the prognostic protocols in resource limited settings across various Hematology centres in India.

Metastatic Calcinosis of Gastric Mucosa.

Calcinosis cutis refers to the deposition of calcium salts in the cutaneous and subcutaneous tissue and is frequently associated with inflammation. Gastric calcinosis can be classified into metastatic, dystrophic, and idiopathic; metastatic calcinosis is the most common type. In metastatic calcification, calcium salts are deposited in normal soft tissues in the setting of altered metabolism of serum calcium and phosphorus and is a rare and serious complication of chronic renal failure. The important factors contributing to the development of metastatic calcinosis are hypercalcemia, hyperphosphatemia, and an elevated calcium-phosphate product. The most striking feature of this diagnosis is the calcification around the large joints. While it mostly involves dermis of small and medium-sized vessels, it can rarely affect the mucosal layers of the gastrointestinal (GI) tract. Calcinosis presents as a marker for the presence of calcifications in other organs, such as heart or lung, which can be life-threatening. Patients rarely present with clinical symptoms of GI upset, dyspepsia, or epigastric pain that are attributed to calcinosis. If patients present with GI symptoms, infectious causes remain to be higher on the differential. We present a case of incidental finding of gastric mucosal calcinosis during the workup and treatment of dysphagia.

Solitary serum methotrexate level 36 hours post high-dose methotrexate: A safe, efficacious, and cost-effective strategy to monitor methotrexate toxicities in childhood leukemia in resource-limited centers.

BACKGROUND: The standard practice during high-dose methotrexate (HD-MTX) in acute lymphoblastic leukemia (ALL) to mitigate toxicity is to serially monitor levels till serum MTX < 0.01 µmol/L. Most resource-limited centers lack in-house access to MTX levels, and therefore repeated monitoring is costly and cumbersome. We studied the efficacy and safety of "solitary 36 hours post HD-MTX levels (MTX36 )." PROCEDURE: This prospective observational study consecutively enrolled children with ALL receiving HD-MTX. Cycles with unavailable MTX36 and MTX36  > 10 µmol/L were excluded. HD-MTX was administered over 24 hours (BFM-2009 protocol) with 12 hours of prehydration. MTX36 were performed at other centers. Leucovorin was given in six hourly doses 36 hours post HD-MTX. Hydration was continued until the last dose of leucovorin. MTX toxicities, including change of creatinine from baseline at 36 hours (∆Cr36 ), were noted. Two groups depending on MTX36 (≤1 µmol/L vs > 1 µmol/L) received six versus eight doses of leucovorin, and toxicities were compared. RESULTS: Twenty-nine children with median age five years (1-11) who received 100 HD-MTX cycles with a median MTX dose of 3 g/m2 (2-5) were analyzed. The median MTX36 level was 1.165 µmol/L (0.1-7.32). Toxicities of HD-MTX (CTCAE-4.0): transaminitis-22%; creatinine elevation ≥ 1.25 times baseline-24%; cytopenias-16%; mucositis-17%; acute kidney injury (AKI)-6%. All toxicities were ≤CTCAE grade 3. Creatinine elevation, AKI, and mucositis were significantly higher in the group with higher MTX36 . There was no correlation (r = 0.3) between ∆Cr36 and MTX36 . MTX36 was thrice more economical than the standard protocol. CONCLUSION: MTX36 is a potential cost-effective, efficacious, and safe limited sample strategy to monitor HD-MTX, particularly in centers where in-house MTX levels are unavailable.