Impact of treatment intensity on infectious complications in patients with acute myeloid leukemia.

BACKGROUND: Infectious complications reflect a major challenge in the treatment of patients with acute myeloid leukemia (AML). Both induction chemotherapy and epigenetic treatment with hypomethylating agents (HMA) are associated with severe infections, while neutropenia represents a common risk factor. Here, 220 consecutive and newly diagnosed AML patients were analyzed with respect to infectious complications dependent on treatment intensity and antifungal prophylaxis applied to these patients. PATIENTS AND METHODS: We retrospectively analyzed 220 patients with newly diagnosed AML at a tertiary care hospital between August 2016 and December 2020. The median age of AML patients undergoing induction chemotherapy (n = 102) was 61 years (25-76 years). Patients receiving palliative AML treatment (n = 118) had a median age of 75 years (53-91 years). We assessed the occurrence of infectious complication including the classification of pulmonary invasive fungal disease (IFD) according to the EORTC/MSG criteria at diagnosis and until day 100 after initiation of AML treatment. Furthermore, admission to intensive care unit (ICU) and subsequent outcome was analyzed for both groups of AML patients, respectively. RESULTS: AML patients subsequently allocated to palliative AML treatment have a significantly higher risk of pneumonia at diagnosis compared to patients undergoing induction chemotherapy (37.3% vs. 13.7%, P < 0.001) including a higher probability of atypical pneumonia (22.0% vs. 10.8%, P = 0.026). Furthermore, urinary tract infections are more frequent in the palliative subgroup at the time of AML diagnosis (5.1% vs. 0%, P = 0.021). Surprisingly, the incidence of pulmonary IFD is significantly lower after initiation of palliative AML treatment compared to the occurrence after induction chemotherapy (8.4% vs. 33.3%, P < 0.001) despite only few patients of the palliative treatment group received Aspergillus spp.-directed antifungal prophylaxis. The overall risk for infectious complications at AML diagnosis is significantly higher for palliative AML patients at diagnosis while patients undergoing induction chemotherapy have a significantly higher risk of infections after initiation of AML treatment. In addition, there is a strong correlation between the occurrence of pneumonia including atypical pneumonia and pulmonary IFD and the ECOG performance status at diagnosis in the palliative AML patient group. Analysis of intensive care unit (ICU) treatment (e.g. in case of sepsis or pneumonia) for both subgroups reveals a positive outcome in 10 of 15 patients (66.7%) with palliative AML treatment and in 15 of 18 patients (83.3%) receiving induction chemotherapy. Importantly, the presence of infections and the ECOG performance status at diagnosis significantly correlate with the overall survival (OS) of palliative AML patients (315 days w/o infection vs. 69 days with infection, P 0.0049 and 353 days for ECOG < 1 vs. 50 days for ECOG > 2, P < 0.001, respectively) in this intent-to-treat analysis. CONCLUSION: The risk and the pattern of infectious complications at diagnosis and after initiation of AML therapy depends on age, ECOG performance status and subsequent treatment intensity. A comprehensive diagnostic work-up for identification of pulmonary IFD is indispensable for effective treatment of pneumonia in AML patients. The presence of infectious complications at diagnosis contributes to an inferior outcome in elderly AML patients.

Exceptional response to neoadjuvant targeted therapy with the selective RET inhibitor selpercatinib in RET-fusion-associated sarcoma.

With the increasing use of next-generation sequencing, highly effective targeted therapies have been emerging as treatment options for several cancer types. Recurrent gene-fusions have been recognized in sarcomas; however, options for targeted therapy remain scarce. Here, we describe a case of a sarcoma, associated with a RET::TRIM33-fusion gene with an exceptional response to a neoadjuvant therapy with the selective RET inhibitor selpercatinib. Resected tumor revealed subtotal histopathologic response. This is the first report of successful targeted therapy with selpercatinib in RET-fusion-associated sarcomas. As new targeted therapies are under development, similar treatment options may become available for sarcoma patients.

Clinical experience with venetoclax in patients with newly diagnosed, relapsed, or refractory acute myeloid leukemia.

BACKGROUND: Diagnosis of acute myeloid leukemia (AML) is associated with poor outcome in elderly and unfit patients. Recently, approval of the BCL-2 inhibitor venetoclax (VEN) in combination with hypo-methylating agents (HMA) led to a significant improvement of response rates and survival. Further, application in the relapsed or refractory (r/r) AML setting or in context of allogeneic stem cell transplantation (alloHSCT) seems feasible. METHODS AND PATIENTS: Fifty-six consecutive adult AML patients on VEN from January 2019 to June 2021 were analyzed retrospectively. Patients received VEN either as first-line treatment, as subsequent therapy (r/r AML excluding prior alloHSCT), or at relapse after alloHSCT. VEN was administered orally in 28-day cycles either combined with HMA or low-dose cytarabine (LDAC). RESULTS: After a median follow-up of 11.5 (range 6.1-22.3) months, median overall survival (OS) from start of VEN treatment was 13.3 (2.2-20.5) months, 5.0 (0.8-24.3) months and 4.0 (1.5-22.1) months for first-line, subsequent line treatment and at relapse post-alloHSCT, respectively. Median OS was 11.5 (10-22.3) months from start of VEN when subsequent alloHSCT was carried out. Relapse-free survival (RFS) for the total cohort was 10.2 (2.2 - 24.3) months. Overall response rate (composite complete remission + partial remission) was 51.8% for the total cohort (61.1% for VEN first-line treatment, 52.2% for subsequent line and 42.8% at relapse post-alloHSCT). Subgroup analysis revealed a significantly reduced median OS in FLT3-ITD mutated AML with 3.4 (1.9-4.9) months versus 10.4 (0.8-24.3) months for non-mutated cases, (HR 4.45, 95% CI 0.89-22.13, p = 0.0002). Patients harboring NPM1 or IDH1/2 mutations lacking co-occurrence of FLT3-ITD showed a survival advantage over patients without those mutations (11.2 (5-24.3) months versus 5.0 (0.8-22.1) months, respectively, (HR 0.53, 95% CI 0.23 - 1.21, p = 0.131). Multivariate analysis revealed mutated NPM1 as a significant prognostic variable for achieving complete remission (CR) (HR 19.14, 95% CI 2.30 - 436.2, p < 0.05). The most common adverse events were hematological, with grade 3 and 4 neutropenia and thrombocytopenia reported in 44.6% and 14.5% of patients, respectively. CONCLUSION: Detailed analyses on efficacy for common clinical scenarios, such as first-line treatment, subsequent therapy (r/r AML), and application prior to and post-alloHSCT, are presented. The findings suggest VEN treatment combinations efficacious not only in first-line setting but also in r/r AML. Furthermore, VEN might play a role in a subgroup of patients with failure to conventional chemotherapy as a salvage regimen aiming for potential curative alloHSCT.

Outcome of patients with relapsed or refractory acute myeloid leukemia treated with Mito-FLAG salvage chemotherapy.

PURPOSE: Curative intended treatment is challenging in patients with relapsed or refractory acute myeloid leukemia (r/r AML) and associated with a dismal prognosis for long-term survival. Despite novel treatment options, the majority of patients are treated with chemotherapy-based regimens. Although widely used, little data exist on the combination of fludarabine, cytarabine, granulocyte colony stimulating factor (FLAG) and mitoxantrone as salvage strategy for r/r AML. MATERIALS AND METHODS: Sixty-six patients receiving Mito-FLAG for r/r AML treated at a German tertiary care center between 2009 and 2019 were analyzed with regard to response rates, survival and safety profile. RESULTS: Overall response rate was 75.8% with 56.1% of patients achieving complete remission (CR) and 19.7% partial remission (PR). After a median follow-up of 54 months, median overall survival (OS) was 13 months. Patients transitioned to allogeneic hematopoietic stem cell transplantation (alloHSCT) (75.8%) showed a significant improvement in OS with a median OS of 17 (95% CI 8.5-25.4) months vs 3 (95% CI 1.7-4.3) months (p < 0.001). 30- and 60-day mortality rates for all patients after the initial cycle of Mito-FLAG were 4.5% and 7.6%, respectively. CONCLUSION: The Mito-FLAG salvage protocol represents an effective and feasible treatment regimen for r/r AML. Importantly, a high rate of transition to successful alloHSCT with the aim of long-term disease-free survival has been shown.

Impact of induction chemotherapy with intermediate-dosed cytarabine and subsequent allogeneic stem cell transplantation on the outcome of high-risk acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) with antecedent hematological disease (s-AML) and treatment-related AML (t-AML) predicts poor prognosis. Intensive treatment protocols of those high-risk patients should consider allogeneic stem cell transplantation (allo-HSCT) in first complete remission (CR). Despite allo-HSCT, relapse rate remains high. Induction chemotherapy with liposomal cytarabine and daunorubicin (CPX-351) has been approved for patients with AML with myeloid-related changes (AML-MRC) or t-AML based on improved survival and remission rates compared to standard 7 + 3 induction. PATIENTS AND METHODS: 110 patients with newly diagnosed s-AML or t-AML at a university hospital were analyzed retrospectively. Median age was 62 years (24-77 years). A total of 65 patients with s-AML after MDS (59%) and 23 patients (20.9%) with t-AML were included. Induction chemotherapy consisted of intermediate-dosed cytarabine (ID-AraC) in combination with idarubicin (patients up to 60 years) or mitoxantrone (patients over 60 years). In patients subsequently undergoing allo-HSCT, reduced conditioning regimens (RIC) were applied prior to transplantation in 47 of 62 patients (76%). RESULTS: Induction chemotherapy with ID-AraC resulted in an overall response rate of 83% including complete remission (CR/CRi) in 69 patients (63%) with a low rate of early death (2.7%). Most relevant non-hematologic toxicity consisted of infectious complications including sepsis with need of intensive care treatment in five patients (4.5%) and proven or probable invasive fungal disease in eight patients (7.2%). Relapse-free survival (RFS), event-free survival (EFS) and overall survival (OS) of the whole cohort were 19 months (0-167), 10 months (0-234) and 15 months (0-234), respectively (p < 0.0001). A significant improvement of OS was observed in patients who underwent allo-HSCT compared to those without subsequent allo-HSCT: 9 vs. 46 months, p < 0.0001. Rate of transplantation-related mortality (TRM) in the early phase post allo-HSCT was low (0.9% at day 30 and 1.8% at day 90, respectively). RIC conditioning results in OS rate of 60% after 60 months post allo-HSCT (median OS not reached). CONCLUSION: S-AML and t-AML patients receiving induction chemotherapy with intermediate-dosed cytarabine showed satisfactory response rate and consolidation therapy with allo-HSCT after full or reduced-intensity conditioning further improved survival in these patients with similar outcome as reported for CPX-351.

Outcome of FLT3-ITD-positive acute myeloid leukemia: impact of allogeneic stem cell transplantation and tyrosine kinase inhibitor treatment.

BACKGROUND: Activating mutations of the receptor tyrosine kinase FLT3 (fms-related tyrosine kinase 3) reflect the most frequent molecular aberration in acute myeloid leukemia (AML). In particular, FLT3 internal tandem duplications (FLT3-ITD) are characterized by an unfavorable prognosis and allogeneic stem cell transplantation (allogeneic SCT) in first complete remission is recommended. In case of imminent or frank relapse following allogeneic SCT, treatment with FLT3 tyrosine kinase inhibitors (TKI) constitutes a promising clinical approach to induce hematologic remission without conventional chemotherapy. PATIENTS AND METHODS: We retrospectively analyzed the response to induction chemotherapy and the outcome of 76 patients with FLT3-ITD-positive AML including 50 patients who underwent allogeneic SCT. Furthermore, efficacy of TKI treatment was evaluated in 18 patients (median age 54 years, range 21-74) with relapsed or refractory FLT3-ITD-positive AML. RESULTS: Response to induction chemotherapy in 76 FLT3-ITD-positive AML patients was characterized by a complete remission (CR) rate of 68%. In total, 50 of 76 patients (66%) underwent allogeneic SCT including 40 patients (80%) in CR. Relapse of AML was observed in 21 of 47 patients (45%) after allogeneic SCT with a median relapse-free survival (RFS) of 13 months (range 3-224) for patients with CR prior to or at day +30 after SCT. Myeloablative conditioning resulted in an improved median RFS of 29 months (4-217) as compared to a reduced intensity conditioning protocol prior to allogeneic SCT with a RFS of 8 months (1-197, P = 0.048), respectively. Median OS of FLT3-ITD-positive AML was 17 months (5-225) for patients who received an allogeneic SCT as compared to 9 months (1-184) for patients who did not undergo SCT. Response of FLT3-ITD-positive AML to sorafenib was characterized by only 3 of 18 patients achieving a bone marrow response (17%), while there was no response to second-line treatment with ponatinib. CONCLUSION: This "real-life" data reflect the continuing challenge of FLT3-ITD-positive AML and confirm the poor outcome even after allogeneic SCT. Furthermore, efficacy of TKI treatment of relapsed or refractory FLT3-ITD AML is still limited and requires substantial improvement, e.g., by the introduction of second-generation inhibitors targeting constitutively active FLT3.

Polymorphisms of Dectin-1 and TLR2 Predispose to Invasive Fungal Disease in Patients with Acute Myeloid Leukemia.

BACKGROUND: Patients with acute myeloid leukemia (AML) who undergo induction chemotherapy are at high risk for invasive fungal disease (IFD). Dectin-1, a C-type lectin family member represents one of the most important pattern recognition receptors of the innate immune system and single nucleotide polymorphisms (SNPs) in the Dectin-1 gene have been associated with an increased risk of infectious complications. We sought to investigate the impact of three different Dectin-1 SNPs and one TLR2 SNP on developing IFD in 186 adult patients with newly diagnosed AML following anthracycline-based induction chemotherapy. PATIENTS AND METHODS: Genotyping of Dectin-1 SNPs (rs16910526, rs3901533 and rs7309123) and TLR2 SNP (rs5743708) was performed by TaqMan method and pyrosequencing. IFD was defined according to the EORTC/MSG consensus guidelines. Multiple logistic regression analyses were applied to evaluate the association between the polymorphisms and the occurrence of pulmonary infections. Dectin-1 expression studies with SNP genotyped human monocytes were performed to elucidate susceptibility to IFD following chemotherapy. RESULTS: We could demonstrate that patients carrying the Dectin-1 SNP rs7309123 G/G (n = 47) or G/G and C/G (n = 133) genotype revealed a significant higher risk for developing both pneumonia in general (adjusted odds ratio (OR): 2.5; p = 0.014 and OR: 3.0, p = 0.004) and pulmonary IFD (OR: 2.6; p = 0.012 and OR: 2.4, p = 0.041, respectively). Patients carrying the TLR2 SNP rs5743708 (R753Q, GA/AA genotype, n = 12) also revealed a significantly higher susceptibility to pneumonia including IFD. Furthermore, Dectin-1 mRNA expression in human monocytes was lower following chemotherapy. CONCLUSION: To our best knowledge, this study represents the first analysis demonstrating that harbouring polymorphisms of Dectin-1 (rs7309123) or TLR2 (rs5743708) represents an independent risk factor of developing IFD in patients with AML undergoing induction chemotherapy.

Efficacy of antifungal prophylaxis with oral suspension posaconazole during induction chemotherapy of acute myeloid leukemia.

BACKGROUND: Severe infectious complications reflect a continuing problem in patients with acute myeloid leukemia (AML). Based on data from a randomized clinical trial demonstrating a reduction of proven and probable invasive fungal disease (IFD), posaconazole has been approved for prophylaxis of fungal infections in AML patients during induction chemotherapy. Nevertheless, recently published observational studies show contradictory results concerning the efficacy of posaconazole in this clinical setting. Furthermore, oral suspension posaconazole is associated with an unpredictable bioavailability that especially depends on nutritional factors or gastric pH value. PATIENTS AND METHODS: We retrospectively analyzed the impact of posaconazole prophylaxis in 70 consecutively evaluable AML patients who underwent induction chemotherapy at a tertiary care hospital. The incidence of IFD classified as proven, probable or possible, antifungal therapy including empiric treatment in high-risk patients and tolerability of posaconazole were determined. In addition, important clinical cofactors such as co-treatment with proton pump inhibitors and risk factors for pneumonia were analyzed in this study. RESULTS: We can demonstrate that posaconazole is well tolerated and had to be stopped in only six patients (8.6%). The overall incidence of IFD was 30% including two patients with proven (2.8%), four patients with probable (5.7%) and 15 patients with possible IFD (21.4%). Importantly, 24 out of 49 patients (49.0%) who did not fulfill the criteria of IFD received empiric antifungal therapy. Including patients classified as possible IFD, 39 of 70 patients (55.7%) underwent at least first-line antifungal treatment. CONCLUSION: Our "real-life" data obtained from 70 AML patients after induction chemotherapy demonstrate the frequent necessity of systemic antifungal treatment despite prophylaxis with oral suspension posaconazole.

Efficacy and feasibility of cyclophosphamide combined with intermediate- dose or high-dose cytarabine for relapsed and refractory acute myeloid leukemia (AML).

BACKGROUND: Approximately, 70 % of adult patients with de novo acute myeloid leukemia (AML) achieve a complete remission (CR) while 10-20 % of AML are refractory to induction chemotherapy. Furthermore, a significant proportion of AML patients in CR will relapse during or after consolidation treatment. There is no evidence for a standard salvage regimen and most centers use a combination of an anthracycline and cytarabine (AraC). The aim of this study was to investigate the impact of two age-adjusted regimens containing AraC and cyclophosphamide applied for the treatment of relapsed or refractory AML. PATIENTS AND METHODS: We retrospectively analyzed 60 patients (24 male, 36 female; median age 56 years) with relapsed or refractory AML who were treated with a combination of AraC and cyclophosphamide monocentrically between October 2000 and January 2013. Two different protocols containing either high-dose (hAC) or intermediate-dose cytarabin (iAC) have been applied dependent on age and performance status. RESULTS: We demonstrate an overall response rate (CR + PR) induced by hAC and iAC of 56.7 %. Importantly, a complete remission rate (CR + CRp) of 52.2 % was found in patients who received the hAC regimen while only 8.8 % of patients achieved a CR following the iAC protocol (p < 0.001). The rate of refractory disease was 26.1 and 47.1 %, respectively. High-risk cytogenetics, i.e., a complex aberrant or monosomal karyotype had no effect on achievement of CR after hAC. In addition, there was no impact of activating FLT3 mutations on response to treatment according to the hAC regimen. In the cohort of patients treated with the iAC protocol, treatment-related mortality of 11.8 % within 60 days was observed but none of the patients who received the hAC regimen died within the first 2 months following chemotherapy. The toxicity profile was acceptable at both cytarabine dose levels. Importantly, 19 patients (82.6 %) of the hAC cohort underwent allogeneic hematopoietic stem cell transplantation (HSCT) as consecutive treatment. CONCLUSION: The hAC regimen represents a promising therapeutic approach to induce a second CR in younger patients with relapsed or refractory AML prior to HSCT without using anthracyclines.