DNA-PKcs-mediated transcriptional regulation of TOP2B drives chemoresistance in acute myeloid leukemia.

Anthracyclines, topoisomerase II enzyme poisons that cause DNA damage, are the mainstay of acute myeloid leukemia (AML) treatment. However, acquired resistance to anthracyclines leads to relapse, which currently lacks effective treatment and is the cause of poor survival in individuals with AML. Therefore, the identification of the mechanisms underlying anthracycline resistance remains an unmet clinical need. Here, using patient-derived primary cultures and clinically relevant cellular models that recapitulate acquired anthracycline resistance in AML, we have found that GCN5 (also known as KAT2A) mediates transcriptional upregulation of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) in AML relapse, independently of the DNA-damage response. We demonstrate that anthracyclines fail to induce DNA damage in resistant cells, owing to the loss of expression of their target enzyme, TOP2B; this was caused by DNA-PKcs directly binding to its promoter upstream region as a transcriptional repressor. Importantly, DNA-PKcs kinase activity inhibition re-sensitized AML relapse primary cultures and cells resistant to mitoxantrone, and abrogated their tumorigenic potential in a xenograft mouse model. Taken together, our findings identify a GCN5-DNA-PKcs-TOP2B transcriptional regulatory axis as the mechanism underlying anthracycline resistance, and demonstrate the therapeutic potential of DNA-PKcs inhibition to re-sensitize resistant AML relapse cells to anthracycline.

Impact of the COVID-19 pandemic on treatment of patients with acute myeloid leukaemia in India.

During the COVID-19 pandemic, our findings highlight changes in AML management strategies in India. There was a decrease in overall patient registrations, particularly at large referral centers, while smaller centers saw an increase, reflecting a shift towards more localized care. This shift was accompanied by a rise in the use of hypomethylating agents (HMAs). Despite these changes, survival outcomes remained comparable to pre-pandemic levels, likely due to improved infection control measures and maintaining treatment protocols. Our study concludes that standard AML care remained feasible during the pandemic, emphasizing the importance of continuing treatment for eligible patients even in times of crisis.

Treatment challenges and outcomes of older patients with acute myeloid leukemia from India.

Globally, overall survival (OS) of older patients with AML continues to be suboptimal with very little data from India. In a multicenter registry analysis, we evaluated 712 patients with AML older than 55 years. Only 323 (45.3%) underwent further treatment, of which 239 (74%) received HMAs, and 60 (18%) received intensive chemotherapy (IC). CR was documented in 39% of those receiving IC and 42% after HMAs. Overall, 100 (31%) patients died within 60 days of diagnosis, most commonly due to progressive disease (47%) or infections (30%). After a median follow-up of 176 days, 228 (76%) of patients had discontinued treatment. At one year from diagnosis, 211 (65%) patients had died, and the median OS was 186 days (IQR, 137-234). Only 12 (3.7%) patients underwent stem cell transplantation. Survival was significantly lower for those older than 60 years (p < 0.001). Patients who died had a higher median age (p = .027) and baseline WBC counts (p = .006). Our data highlights suboptimal outcomes in older AML patients, which are evident from 55 years of age onwards, making it necessary to evaluate HMA and targeted agent combinations along with novel consolidation strategies to improve survival in this high-risk population.

Long-term clinical outcomes of combined modality therapy for advanced-stage Hodgkin lymphoma in the PET era: A retrospective study.

BACKGROUND OBJECTIVES: The role of consolidation radiation therapy (CRT) after complete metabolic response to chemotherapy in advanced-stage (stage III and IV) Hodgkin lymphoma (HL) is controversial. This study was undertaken to assess the clinical outcomes in terms of event free survival, local failure free survival and overall survival in individuals with advanced HL treated with chemotherapy and CRT. METHODS: A retrospective review was conducted to study the long-term clinical outcomes in individuals diagnosed with HL and treated with chemotherapy and CRT from 2012 to 2016 at a tertiary cancer care hospital in India. RESULTS: Data from 203 study participants with advanced-stage HL were analyzed. Positron emission tomography-computed tomography (PET-CT) was done at baseline and after 2 cycles for response assessment. The median age at presentation was 32 yr [interquartile range (IQR): 26-46]. Early metabolic response (after 2 cycles) and delayed metabolic response (after 4 or 6 cycles) were observed in 74.4 and 25.6 per cent of individuals, respectively. With a median follow up of 52 months (IQR: 40-67), the five-year event-free survival (EFS), local failure-free survival (LFFS) and overall survival (OS) were 83.2, 95.1 and 94.6 per cent, respectively. On univariate analysis, extranodal disease was associated with inferior EFS (P=0.043). Haemoglobin <10.5 g/dl (P=0.002) and Hasenclever index >3 (P=0.00047) were associated with poorer OS. Relapses were observed in 28/203 (13.8%) study participants with predominance at central nodal stations. The median time to relapse was 19.4 months (IQR: 13-33). Local relapse alone (at the irradiated site) was observed in 5/28 study participants, systemic (distant) relapse in 14/28 individuals, while both systemic and local relapse was observed in 9/28 participants. Extranodal disease (P=0.05), bulky disease (P=0.005) and haemoglobin concentration ≤10.5 g/dl (P=0.036) were significant predictors for disease relapse. INTERPRETATION CONCLUSIONS: Individuals with advanced-stage HL treated with anthracycline-based chemotherapy (anthracycline-based chemotherapy with doxorubicin, bleomycin, vinblastine and dacarbazine regimen) and CRT had excellent long-term outcomes. As isolated infield failures are uncommon, selective consolidation with conformal RT to high-risk sites improves final disease outcomes.

Phase II trial of a novel chemotherapy regimen CVEP (cyclophosphamide, vinblastine, etoposide and prednisolone) for acquired immunodeficiency syndrome (AIDS)-associated lymphomas.

Management of acquired immunodeficiency syndrome (AIDS)-related diffuse large B-cell (DLBCL) and plasmablastic lymphomas (PBL) poses significant challenges. The evidence supports use of dose-adjusted EPOCH (etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin) with or without rituximab as first-line therapy. The need for central venous access, growth factors and significant toxicities limits its use in resource-constrained settings. To address these challenges, we have developed a novel regimen, CVEP (cyclophosphamide, vinblastine, etoposide, and prednisolone) based on the pharmacodynamic principles of dose-adjusted EPOCH. This single-centre phase II study evaluated the efficacy and safety of CVEP regimen in patients with de novo systemic AIDS-related DLBCL and PBL. The primary objective was complete response (CR) rates as assessed by positron emission tomography-computed tomography. The secondary objectives were incidence of Grade 3/4 toxicities, toxicities requiring hospitalisation, and disease-free survival. From May 2011 to February 2017, 42 patients were enrolled. At the end of therapy the CR rates were 69% (29/42) in the intention-to-treat population and 80.5% (29/36) in evaluable patients. At a median follow-up of 69 months, the 5-year disease-free survival was 65.3%. Out of 217 cycles administered, febrile neutropenia occurred in 19.3% and hospitalisation was required in 18.3% of cycles. There were two treatment-related deaths. The CVEP regimen is an active and safe regimen for AIDS-related DLBCL and PBL.

Navigating the neutropenic abyss with granulocyte transfusions: Retrospective single-center analysis of effectiveness and safety in India.

BACKGROUND: Hemato-oncologic patients receiving intensive chemotherapy may develop severe neutropenia and serious bacterial and/or fungal infections. Granulocyte transfusions (GTs) may be beneficial as a bridging therapy in hemato-oncologic patients with febrile neutropenia. AIM: To evaluate the clinical effectiveness of GTs in hemato-oncologic patients with febrile neutropenia. MATERIALS AND METHODS: This retrospective study evaluated the effectiveness of 150 GTs in 88 hemato-oncologic patients. Donors were mobilized with granulocyte colony-stimulating factors and dexamethasone. Patients' hematological parameters (pre- and post-GT) and safety and effectiveness of GTs were analyzed. RESULTS: The safety and effectiveness of GTs were assessed in the patients with various underlying conditions, including 78% with acute myeloid leukemia. In total, 150 GTs were administered, mostly during the chemotherapy induction phase. The GTs were well-tolerated by the patients, and a significant increment in white blood cell count and absolute neutrophil count (ANC) was noticed in 95% of patients after the transfusion. The granulocyte dose was positively correlated with ANC after the transfusion. The average time to neutrophil recovery from the last day of GT was 6.7 days, and the 30-day survival rate was 77%. The donors were all men, and a significant increase in WBC count was observed post-mobilization. The median granulocyte yield was 2.28 × 1010 /unit. All granulocyte products were crossmatched and irradiated before the transfusion. CONCLUSION: GTs can be a useful adjunctive treatment for febrile neutropenia in hemato-oncologic patients with multidrug-resistant sepsis. However, additional studies are required for confirming their effectiveness and establishing guidelines for their use.

Role of cytogenetic abnormalities detected by fluorescence in situ hybridization as a prognostic marker: Pathogenesis & clinical course in patients with B-chronic lymphocytic leukaemia.

BACKGROUND & OBJECTIVES: B-cell chronic lymphocytic leukaemia (B-CLL) is one of the most common forms of adult leukaemia, with a highly variable clinical course. Specific chromosomal and genetic aberrations are used clinically to predict prognosis, independent from conventional clinical markers. Molecular cytogenetic methods such as fluorescence in situ hybridization (FISH) detect aberrations in up to 80 per cent B-CLL patients. This study was conducted to score the frequencies of recurrent aberrations, i.e., del(13q14), trisomy 12, del(11q22), del(17p13), del(6q21) and IgH (immunoglobulin heavy chain) translocations and to understand their role in prognostication and risk stratification. METHODS: FISH studies were performed on bone marrow aspirate or peripheral blood of 280 patients using commercially available disease-specific probe set. The data were correlated with clinical and haematological parameters such as low haemoglobin, splenomegaly and lymphadenopathy. RESULTS: Chromosomal aberrations were detected in 79 per cent of patients, with del(13q14) (57%) as the most common cytogenetic aberration, followed by trisomy 12 (27%), del(11q22) (22%), t(14q32) (19%), del(17p13) (18%) and del(6q21) (9%). Single or in coexistence with other aberration del(13q14) had a favourable outcome in comparison to del(11q22), t(14q32), del(17p13) and del(6q21) which were associated with advanced stages of the disease. Trisomy 12 had a variable clinical course. INTERPRETATION & CONCLUSIONS: FISH was found to be a sensitive and efficient technique in detecting the prevalence of recurrent cytogenetic abnormalities. Each of these aberrations is an important independent predictor of disease progression and survival which aids in designing risk-adapted treatment strategies for better disease management.

Investigating the clinical, hematological and cytogenetic profile of endoreduplicated hypodiploids in BCP-ALL.

Ploidy, besides known translocations in lymphoblasts, is a strong predictor of prognosis in B- cell progenitor acute lymphoblastic leukemia (BCP-ALL). While hyperdiploidy with >50 chromosomes shows a favourable outcome, hypodiploidy with <45 chromosomes have a dismal clinical outcome. However, there exists a small subset where both the hypodiploid and hyperdiploid clones are apparent either by cytogenetics or flow cytometry and are defined partially masked hypodiploids or mosaics based on the percentage of clonal population. These patients are essentially hypodiploids, and show the hyperdiploid clone as a consequence of endoreduplication of the primary hypodiploid clone- A phenomenon of successive replication of genome without mitosis (cytokinesis) resulting in increased ploidy. In the current study, we present the complete clinical, hematological and cytogenetic profile of 11 such newly diagnosed mosaics or partially masked hypodiploid BCP-ALL cases.

Over expression of brain and acute leukemia, cytoplasmic and ETS-related gene is associated with poor outcome in acute myeloid leukemia.

The high expression of brain and acute leukemia, cytoplasmic (BAALC) and ETS-related gene (ERG) has been reported to influence the outcome in acute myeloid leukemia (AML), but due to limited prospective studies, their role as prognostic factors is unclear. At diagnosis, the prognostic value of BAALC and ERG expression with respect to other cytogenetic and molecular markers was analyzed in 149 AML patients. Patients were divided into quartiles which resulted in the formation of four groups (G1-G4) based on expression values of BAALC and ERG and clinical response defined across groups. Groups with similar survival probabilities were merged together and categorized subsequently as high versus low expressers. Patients with high BAALC and ERG expression had significantly lower overall survival (OS; BAALC: p = 0.001 at 5 years 29.4% vs. 69.8%; ERG: p < 0.0001 at 5 years 4% vs. 50.4%) and disease-free survival (BAALC: p = 0.001 at 5 years 19.5% vs. 69.8%; ERG: p < 0.0001 at 5 years 4.2% vs. 47%). Patients were further stratified combining BAALC and ERG expression in an integrative prognostic risk score (IPRS). After a median follow-up of 54 months (95% CI 45-63 months) among survivors, IPRS for high versus low expressers was a significant predictor for OS (BAALC + ERG: 4% vs. 71.6%, p < 0.0001) and DFS (BAALC + ERG: 4.5% vs. 74.1%, p < 0.0001). In a multivariate model, IPRS of BAALC + ERG expression retained prognostic significance for OS (hazard ratio [HR] 2.96, 95%CI 1.91-4.59, p < 0.001) and DFS (HR 3.61, 95%CI 2.26-5.76, p < 0.001).

Study of stem cell homing & self-renewal marker gene profile of ex vivo expanded human CD34+ cells manipulated with a mixture of cytokines & stromal cell-derived factor 1.

BACKGROUND & OBJECTIVES: Next generation transplantation medicine aims to develop stimulating cocktail for increased ex vivo expansion of primitive hematopoietic stem and progenitor cells (HSPC). The present study was done to evaluate the cocktail GF (Thrombopoietin + Stem Cell factor + Flt3-ligand) and homing-defining molecule Stromal cell-derived factor 1 (SDF1) for HSPC ex vivo expansion. METHODS: Peripheral blood stem cell (n=74) harvests were analysed for CD34hiCD45lo HSPC. Immunomagnetically enriched HSPC were cultured for eight days and assessed for increase in HSPC, colony forming potential in vitro and in vivo engrafting potential by analyzing human CD45+ cells. Expression profile of genes for homing and stemness were studied using microarray analysis. Expression of adhesion/homing markers were validated by flow cytometry/ confocal microscopy. RESULTS: CD34hiCD45lo HSPC expansion cultures with GF+SDF1 demonstrated increased nucleated cells (n=28, P+ cells (n=8, P=0.021) and increased colony forming units (cfu) compared to unstimulated and GF-stimulated HSPC. NOD-SCID mice transplanted with GF+SDF1-HSPC exhibited successful homing/engraftment (n=24, PInterpretation & conclusions: Cocktail of cytokines and SDF1 showed good potential to successfully expand HSPC which exhibited enhanced ability to generate multilineage cells in short-term and long-term repopulation assay. This cocktail-mediated stem cell expansion has potential to obviate the need for longer and large volume apheresis procedure making it convenient for donors.

Hepatitis B-related serological events in hematopoietic stem cell transplant patients and efficacy of lamivudine prophylaxis against reactivation.

Reactivation of remote hepatitis B infection (RHBI) is an important cause of morbidity in hematopoietic cell transplant (HCT) patients. We analyzed the prevalence of RHBI in 205 patients who underwent HCT in our centre, serological events related to hepatitis B virus (HBV) reactivation and role of lamivudine prophylaxis in HCT patients with RHBI. The prevalence of RHBI was 14% (28/205 patients). Of these 28 patients, 15 received lamivudine prophylaxis (14 anti-HBcIgG positive and 1 only anti-HBs positive) while 13 did not receive lamivudine prophylaxis (12 anti-HBs positive and 1 anti-HBcIgG positive). None in prophylaxis group developed HBV reactivation while 12 of 13 in no-prophylaxis group reactivated (P < 0.001). The rate of HBV reactivation was 10% (21/205 patients), which included 9 patients with no evidence of RHBI pre-transplant. We conclude that lamivudine prophylaxis protects against HBV reactivation in HCT patients with evidence of RHBI. Lamivudine prophylaxis should be used not only in patients with anti-HBcIgG positivity but also in those with isolated anti-HBs positivity pre-transplant given the high rate of HBV reactivation in these patients. HBV serology cannot identify all cases with RHBI and therefore does not preclude HBV reactivation post-transplant. Copyright © 2015 John Wiley & Sons, Ltd.

Minimal Residual Disease in the Management of B-Cell Acute Lymphoblastic Leukemia: A Systematic Review of Studies from Indian Settings.

Minimal residual disease (MRD) has become an essential tool in the management of B-cell acute lymphoblastic leukemia (B-ALL) and aids in tailoring treatment strategies to suit specific patient needs. Although much progress has been made in this area, there is limited data on the use of MRD in the Indian context. Our objective was to identify relevant literature that discusses the utility of MRD in the management of B-cell ALL in adolescents and young adults (AYA) and adults in Indian settings. A systematic search and screening of articles were performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The primary data source was PubMed followed by Google Scholar for articles and conference proceedings. Of the 254 records screened, 24 records were retained for analysis. MRD monitoring had a significant role in the management of AYA/adult B-cell ALL patients. Variability of results was observed across these studies with respect to methods, techniques, and use. However, these studies evidenced and validated the importance of MRD assessment in risk-adapted management of B-cell ALL and highlighted the need for optimization. The advances in MRD diagnostics and applications are yet to be tested and adopted in Indian settings. Hence, there is a need for in-depth research to develop and optimize approaches for calibrating country-specific management strategies. The potential role of MRD assessments in anticipating relapse or treatment failures warrants more attention for the preemptive positioning of novel strategies involving immunotherapies.

Mitocurcumin utilizes oxidative stress to upregulate JNK/p38 signaling and overcomes Cytarabine resistance in acute myeloid leukemia.

Acute myeloid leukemia (AML) is a type of blood cancer that is characterized by the rapid growth of abnormal myeloid cells. The goal of AML treatment is to eliminate the leukemic blasts, which is accomplished through intensive chemotherapy. Cytarabine is a key component of the standard induction chemotherapy regimen for AML. However, despite a high remission rate, 70-80% of AML patients relapse and develop resistance to Cytarabine, leading to poor clinical outcomes. Mitocurcumin (MitoC), a derivative of curcumin that enters mitochondria, leading to a drop in mitochondrial membrane potential and mitophagy induction. Further, it activates oxidative stress-mediated JNK/p38 signaling to induce apoptosis. MitoC demonstrated a preferential ability to kill leukemic cells from AML cell lines and patient-derived leukemic blasts. RNA sequencing data suggests perturbation of DNA damage response and cell proliferation pathways in MitoC-treated AML. Elevated reactive oxygen species (ROS) in MitoC-treated AML cells resulted in significant DNA damage and cell cycle arrest. Further, MitoC treatment resulted in ROS-mediated enhanced levels of p21, which leads to suppression of CHK1, RAD51, Cyclin-D and c-Myc oncoproteins, potentially contributing to Cytarabine resistance. Combinatorial treatment of MitoC and Cytarabine has shown synergism, increased apoptosis, and enhanced DNA damage. Using AML xenografts, a significant reduction of hCD45+ cells was observed in AML mice bone marrow treated with MitoC (mean 0.6%; range0.04%-3.56%) compared to control (mean 38.2%; range10.1%-78%), p = 0.03. The data suggest that MitoC exploits stress-induced leukemic oxidative environment to up-regulate JNK/p38 signaling to lead to apoptosis and can potentially overcome Cytarabine resistance via ROS/p21/CHK1 axis.

Fludarabine melphalan versus fludarabine treosulfan for reduced intensity conditioning regimen in allogeneic hematopoietic stem cell transplantation: a retrospective analysis.

Various reduced-intensity conditioning (RIC) regimens are used to decrease toxicity while providing comparable outcomes to myeloablative regimens. We compared toxicity and outcomes between two RIC regimens, fludarabine with melphalan (Flu-Mel) and fludarabine with treosulfan (Flu-Treo), retrospectively over a 10-year period in two donor groups, matched related donor (MRD)/matched unrelated donor (MUD) and haploidentical (Haplo) transplants. The study included 138 patients, of which 105 received MRD/MUD (Flu-Mel: 94, Flu-Treo: 11) and 33 Haplo (Flu-Mel: 17, Flu-Treo: 16) transplants. In the MRD/MUD group, 44 (47%) of patients who received Flu-Mel had grade 3/4 oral mucositis compared to 1 (9%) who received Flu-Treo (P = 0.02). Corresponding numbers in the Haplo group were 7 (41%) and 1 (6%). Grade 3/4 diarrhoea was more frequent with Flu-Mel than Flu-Treo in the Haplo group (41% vs 6%; P = 0.039), but not the MRD/MUD group. Median follow-up time for all patients was 4.8 years. Five-year OS in the MRD/MUD group was 62% with Flu-Mel versus 53% with Flu-Treo (P = 0.0694). Similarly, 5-year OS was 41% with Flu-Mel and 28% with Flu-Treo (P = 0.770) in the Haplo group. Severe mucositis and diarrhoea were significantly less frequent with Flu-Treo than Flu-Mel. Flu-Treo provided comparable outcomes to Flu-Mel in all donor transplants.

A Retrospective Cohort Study to Evaluate the Outcomes of HIV-Associated High-Grade B-Cell Non-Hodgkin Lymphoma (NHL) Treated with Dose Adjusted EPOCH (+/-R) Regimen.

High-grade B-cell NHL's are more common in seropositive patients. They are biologically different from their seronegative counterparts. We report our analysis on our cohort of patients who were treated with DA-EPOCH(+/-R). We retrospectively analyzed treatment-naïve HIV-associated High-grade B-cell NHL patients (aged ≥ 18) treated with DA-EPOCH(+/-R) regimen from 2011 to 2015. Descriptive statistics were summarized with median and range; survival outcomes were analyzed with Kaplan-Meier method. The cohort comprised of 40 patients [DLBCL(19), Burkitt's Lymphoma(16), High-grade B-Cell Lymphoma-Unclassifiable(09), and Plasmablastic Lymphoma(01)] and the median CD4 + T cell count was 202/mm3. CNS prophylaxis was administered with intrathecal methotrexate to 90% of patients. With a median follow-up of 72 months, an estimated 5-year OS was 82.5%, and 5-PFS was 77.5%. There were 9 deaths, and 9 patients had progression. At least 4 cycles of chemotherapy were administered to 35 (93%) patients, with 28 (70%) receiving 6 cycles. Grade 3-4 toxicities were seen in 33 (83%) patients- febrile neutropenia (65%) being the most common followed by mucositis (25%) and peripheral neuropathy (13%). There was no difference in survival based on IPI, CD 4 + T cell count, CDI, or duration of HIV. DA-EPOCH(+/-R) is a highly effective regimen in seropositive high-grade B-cell lymphoma, even in the presence of adverse features. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-023-01652-3.

A Prospective Study to Evaluate the Effect of Therapeutic Drug Monitoring-Based Posaconazole Prophylaxis on Invasive Fungal Infection Rate During Acute Myeloid Leukemia Induction Therapy.

Invasive fungal infections (IFIs) are a significant cause of morbidity and mortality in de-novo acute myeloid leukemia patients receiving induction chemotherapy. Despite using posaconazole, a broad-spectrum antifungal, for IFI prophylaxis, the breakthrough IFI rate is high in the real-world setting. One of the reasons could be frequent suboptimal plasma posaconazole levels. In the present study, we evaluated if therapeutic drug monitoring (TDM) guided posaconazole prophylaxis can reduce the IFI rates in comparison to a historical cohort. We enrolled 90 patients, > / = 16 years of age, without baseline IFIs, planned for remission induction therapy. All patients were started on posaconazole suspension 200 mg TDS and the dose was increased in a stepwise manner if trough levels were found to be suboptimal (< 350 ng/ml for day 2 or < 700 ng/ml subsequently). The TDM based approach resulted in a significant decline in breakthrough IFI rates (18% versus 52%, P < 0.0001) A total of 69 patients (78%) required dose escalation. Thirty-one patients required change in antifungals due to either suboptimal levels, persistent fever, diarrhoea or vomiting. We could not demonstrate an exposure-response relationship but the difference in IFI rates in patients with a median posaconazole level > / = 700 ng/ml (0%) and < 700 ng/ml (21.6%) was clinically meaningful. Posaconazole levels were found to be significantly lower in patients on antacids and prokinetics. The incidence of posaconazole-related grade 3 toxicity was low (2.3%). Thus TDM-based dosing of posaconazole helps reduce breakthrough IFI rate and should be a part of posaconazole prophylaxis. Supplementary Information: The online version contains supplementary material available at 10.1007/s12288-023-01709-3.

Real World Outcomes with Treatment Free Remission in Chronic Myeloid Leukemia-Experience from a Tertiary Care Cancer Centre.

Chronic myeloid leukaemia (CML) is caused by balanced translocation t(9::22)(q34;q11) resulting in formation of pathogenic BCR-ABL fusion gene. Tyrosine kinase inhibitors (TKI) have revolutionised the treatment of CML. Ongoing treatment with TKI leads to side effects and has financial impact. Teratogenic potential of TKI and growth disturbance also represent an important challenge. Thus, TKI discontinuation in form of treatment free remission (TFR) has emerged as a new and important therapeutic goal. In this retrospective study, we reviewed CML patients who were kept on TFR. Inclusion criteria was patient age ≥ 18 years diagnosed with CML in chronic phase who met the criteria for TFR and opted for same and who were in DMR but stopped TKI for any reason. We analysed the data for baseline characteristics, molecular relapse (MR), survival without molecular relapse (SWMR), TFR duration and factors affecting MR. We included 38 patients in this analysis. Thirty five (92%) patients were treated with imatinib at diagnosis. Median duration of TKI treatment was 135 months. 37 patients (97.5%) achieved DMR on TKI and median time from TKI initiation to DMR was 96 months. Median duration of DMR prior to TKI discontinuation was 41 months. TKI was discontinued after counselling for TFR in 26 patients (68%) while it was discontinued due to intolerance in 10 patients (29%). At median molecular follow up of 25 months, nine patients (23.7%) had molecular relapse. Median SWMR was not reached and 2 year estimated SWMR was 65.2% (95%CI,47.2- 83.2). Of all relapses, 5/9 (55.5%) occurred in the first six months of TFR. On univariate analysis, duration of TKI and duration of DMR were predictive of molecular relapse. On multivariate analysis, none of these factors were found to be significant. This retrospective study suggests that for CML CP patients achieving deep molecular response, discontinuing TKI therapy in real-world settings may be feasible while potentially achieving comparable outcomes.