Acalabrutinib-based regimens in frontline or relapsed/refractory higher-risk CLL: pooled analysis of 5 clinical trials.

ABSTRACT: Before targeted therapies, patients with higher-risk chronic lymphocytic leukemia (CLL), defined as del(17p) and/or TP53 mutation (TP53m), unmutated immunoglobulin heavy chain variable region genes (uIGHV), or complex karyotype (CK), had poorer prognosis with chemoimmunotherapy. Bruton tyrosine kinase inhibitors (BTKis) have demonstrated benefit in higher-risk patient populations with CLL in individual trials. To better understand the impact of the second-generation BTKi acalabrutinib, we pooled data from 5 prospective clinical studies of acalabrutinib as monotherapy or in combination with obinutuzumab (ACE-CL-001, ACE-CL-003, ELEVATE-TN, ELEVATE-RR, and ASCEND) in patients with higher-risk CLL in treatment-naive (TN) or relapsed/refractory (R/R) cohorts. A total of 808 patients were included (TN cohort, n = 320; R/R cohort, n = 488). Median follow-up was 59.1 months (TN cohort) and 44.3 months (R/R cohort); 51.3% and 26.8% of patients in the TN and R/R cohorts, respectively, remained on treatment at last follow-up. In the del(17p)/TP53m, uIGHV, and CK subgroups in the TN cohort, median progression-free survival (PFS) and median overall survival (OS) were not reached (NR). In the del(17p)/TP53m, uIGHV, and CK subgroups in the R/R cohort, median PFS was 38.6 months, 46.9 months, and 38.6 months, respectively, and median OS was 60.6 months, NR, and NR, respectively. The safety profile of acalabrutinib-based therapy in this population was consistent with the known safety profile of acalabrutinib in a broad CLL population. Our analysis demonstrates long-term benefit of acalabrutinib-based regimens in patients with higher-risk CLL, regardless of line of therapy.

Author Correction: HER kinase inhibition in patients with HER2- and HER3-mutant cancers.

The 'Competing interests' statement of this Article has been updated; please see the accompanying Amendment. The original Article has not been corrected online.

HER kinase inhibition in patients with HER2- and HER3-mutant cancers.

Somatic mutations of ERBB2 and ERBB3 (which encode HER2 and HER3, respectively) are found in a wide range of cancers. Preclinical modelling suggests that a subset of these mutations lead to constitutive HER2 activation, but most remain biologically uncharacterized. Here we define the biological and therapeutic importance of known oncogenic HER2 and HER3 mutations and variants of unknown biological importance by conducting a multi-histology, genomically selected, 'basket' trial using the pan-HER kinase inhibitor neratinib (SUMMIT; clinicaltrials.gov identifier NCT01953926). Efficacy in HER2-mutant cancers varied as a function of both tumour type and mutant allele to a degree not predicted by preclinical models, with the greatest activity seen in breast, cervical and biliary cancers and with tumours that contain kinase domain missense mutations. This study demonstrates how a molecularly driven clinical trial can be used to refine our biological understanding of both characterized and new genomic alterations with potential broad applicability for advancing the paradigm of genome-driven oncology.

A randomized controlled trial testing an adherence-optimized Vitamin D regimen to mitigate bone change in adolescents being treated for acute lymphoblastic leukemia.

Adolescents with acute lymphoblastic leukemia (ALL) develop osteopenia early in therapy, potentially exacerbated by high rates of concurrent Vitamin D deficiency. We conducted a randomized clinical trial testing a Vitamin D-based intervention to improve Vitamin D status and reduce bone density decline. Poor adherence to home supplementation necessitated a change to directly observed therapy (DOT) with intermittent, high-dose Vitamin D3 randomized versus standard of care (SOC). Compared to SOC, DOT Vitamin D3 successfully increased trough Vitamin 25(OH)D levels (p = .026) with no residual Vitamin D deficiency, 100% adherence to DOT Vitamin D3, and without associated toxicity. However, neither Vitamin D status nor supplementation impacted bone density. Thus, this adherence-optimized intervention is feasible and effective to correct Vitamin D deficiency in adolescents during ALL therapy. Repletion of Vitamin D and calcium alone did not mitigate osteopenia, however, and new, comprehensive approaches are needed to address treatment-associated osteopenia during ALL therapy.

Comparative Toxicity by Sex Among Children Treated for Acute Lymphoblastic Leukemia: A Report From the Children's Oncology Group.

BACKGROUND: Epidemiologic studies find sex-based differences in incidence, survival, and long-term outcomes for children with cancer. The purpose of this study was to determine whether male and female patients differ with regard to acute treatment-related toxicities. PROCEDURES: We reviewed data collected on the Children's cancer group (CCG) high-risk acute lymphoblastic leukemia (ALL-HR) study (CCG-1961), and compared male and female patients' toxicity incidence and related variables in the first four phases of treatment. Similar analyses were performed with standard-risk ALL (ALL-SR) patients enrolled in CCG-1991. RESULTS: Among ALL-HR patients, females had significantly more hospital days, delays in therapy, grade 3 or 4 toxicities (e.g., gastrointestinal, liver), and supportive care interventions (e.g., transfusions, intravenous antibiotics) than males. Females were significantly more likely to have died of treatment-related causes than males (Hazard ratio = 2.8, 95%CI = 1.5-5.3, P = 0.002). Five months after beginning the treatment, the cumulative incidence of treatment-related deaths was 2.6% for females and 1.2% for males. Similar disparities were found among ALL-SR patients, with females experiencing significantly more hospital days and treatment-related toxicities than males. CONCLUSIONS: This study complements cancer survivorship studies that also report an increase in treatment-related late effects among females. Risk profiles appear to be different for male and female patients, with females having greater risk of developing both acute and long-term treatment-related toxicities. The underlying biological mechanisms for these sex differences are poorly understood and warrant further study in order to determine how sex-based outcome disparities can be addressed in future clinical trials and practice.

Infectious complications in the first year following autologous hematopoietic progenitor cell rescue for children with brain tumors.

BACKGROUND: High-dose chemotherapy with autologous hematopoietic progenitor cell rescue (AuHPCR) for pediatric patients with brain tumors has become an important therapeutic modality to avoid or delay the long-term effects of cranial irradiation. Data on post-AuHPCR infectious complications in this population are lacking. This single institution retrospective review reports the prophylactic practices and infections in the first year following AuHPCR in pediatric patients with brain tumors. PROCEDURE: The medical record of patients who underwent AuHPCR for the treatment of a malignant brain tumor at Children's Hospital Los Angeles between 1988 and 2010 were reviewed. Patients without prior irradiation who were free of disease at 1 year without additional chemotherapy were evaluated for all infectious disease complications occurring from time of neutrophil engraftment to 1 year post-AuHPCR. RESULTS: Forty-three of the 115 eligible patients were included. The median time to neutrophil engraftment was 11 days (range: 8-43 days), and 20 Grade III/IV (no Grade V) infectious episodes developed in 15 patients (35%). Fourteen episodes of bacteremia (70%) were catheter-related, predominantly gram-negative (71%), and polymicrobial (50%). There were no fungal or pneumocystis infections and only 1 of 25 (4%) at-risk patients developed VZV reactivation. CONCLUSIONS: These data suggest patients with brain tumors undergoing AuHPCR have few late-occurring non-catheter-related post-transplant infections indicating that prophylaxis practices were sufficient. Central lines should be removed soon after engraftment, but those with central line infections should receive adequate treatment including gram-negative coverage. In addition, only at-risk patients who receive further irradiation may benefit from VZV reaction prophylaxis.

Adipocytes cause leukemia cell resistance to L-asparaginase via release of glutamine.

Obesity is a significant risk factor for cancer. A link between obesity and a childhood cancer has been identified: obese children diagnosed with high-risk acute lymphoblastic leukemia (ALL) had a 50% greater risk of relapse than their lean counterparts. l-asparaginase (ASNase) is a first-line therapy for ALL that breaks down asparagine and glutamine, exploiting the fact that ALL cells are more dependent on these amino acids than other cells. In the present study, we investigated whether adipocytes, which produce significant quantities of glutamine, may counteract the effects of ASNase. In children being treated for high-risk ALL, obesity was not associated with altered plasma levels of asparagine or glutamine. However, glutamine synthetase was markedly increased in bone marrow adipocytes after induction chemotherapy. Obesity substantially impaired ASNase efficacy in mice transplanted with syngeneic ALL cells and, like in humans, without affecting plasma asparagine or glutamine levels. In coculture, adipocytes inhibited leukemic cell cytotoxicity induced by ASNase, and this protection was dependent on glutamine secretion. These findings suggest that adipocytes work in conjunction with other cells of the leukemia microenvironment to protect leukemia cells during ASNase treatment.

Diet-induced obesity accelerates acute lymphoblastic leukemia progression in two murine models.

Obesity is associated with an increased incidence of many cancers, including leukemia, although it is unknown whether leukemia incidence is increased directly by obesity or rather by associated genetic, lifestyle, health, or socioeconomic factors. We developed animal models of obesity and leukemia to test whether obesity could directly accelerate acute lymphoblastic leukemia (ALL) using BCR/ABL transgenic and AKR/J mice weaned onto a high-fat diet. Mice were observed until development of progressive ALL. Although obese and control BCR/ABL mice had similar median survival, older obese mice had accelerated ALL onset, implying a time-dependent effect of obesity on ALL. Obese AKR mice developed ALL significantly earlier than controls. The effect of obesity was not explained by WBC count, thymus/spleen weight, or ALL phenotype. However, obese AKR mice had higher leptin, insulin, and interleukin-6 levels than controls, and these obesity-related hormones all have potential roles in leukemia pathogenesis. In conclusion, obesity directly accelerates presentation of ALL, likely by increasing the risk of an early event in leukemogenesis. This is the first study to show that obesity can directly accelerate the progression of ALL. Thus, the observed associations between obesity and leukemia incidence are likely to be directly related to biological effects of obesity.

The challenges of high-dose chemotherapy in CNS tumors.

High-dose, myeloablative chemotherapy with hematopoietic stem cell rescue is used in children and young adults with brain tumors for which conventional therapy is either excessively toxic (e.g., radiotherapy in infants) or ineffective. Thus, the aims of such strategies are to improve both quantity and quality of life. Whether high-dose chemotherapy is less neurotoxic and more effective than other therapeutic approaches is still controversial. We will consider the difficulties in analyzing published data and the challenges of designing effective clinical trials that test high-dose chemotherapy in patients with brain tumors.

Adipocytes impair leukemia treatment in mice.

Obesity is associated with increased cancer incidence and mortality. We have previously found that obesity in children is associated with a 50% increased recurrence of acute lymphoblastic leukemia (ALL) in high-risk patients. We have therefore developed novel in vivo and in vitro preclinical models to study the mechanism(s) of this association. Obesity increased relapse after monotherapy with vincristine (P = 0.03) in obese mice injected with syngeneic ALL cells. This occurred although the drug was dosed proportionally to body weight, equalizing blood and tissue drug levels. In coculture, 3T3-L1 adipocytes significantly impaired the antileukemia efficacy of vincristine, as well as three other chemotherapies (P < 0.05). Interestingly, this protection was independent of cell-cell contact, and it extended to human leukemia cell lines as well. Adipocytes prevented chemotherapy-induced apoptosis, and this was associated with increased expression of the two prosurvival signals Bcl-2 and Pim-2. These findings highlight the role of the adipocyte in fostering leukemia chemotherapy resistance, and may help explain the increased leukemia relapse rate in obese children and adults. Given the growing prevalence of obesity worldwide, these effects are likely to have increasing importance to cancer treatment.

High-dose chemotherapy and autologous hematopoietic progenitor cell rescue in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors: the impact of prior radiotherapy on outcome.

BACKGROUND: The role of myeloablative chemotherapy in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors (MB/ST-PNET) is controversial, in particular in patients who develop recurrent disease after craniospinal radiotherapy. METHODS: In this retrospective analysis, the authors investigated the outcome of children with recurrent MB/ST-PNET who were referred for myeloablative chemotherapy and autologous hematopoietic progenitor cell rescue at Childrens Hospital Los Angeles. RESULTS: Thirty-three children were referred for myeloablative chemotherapy: Fourteen of those children were never transplanted because of pre-transplant adverse events, and 19, including 6 without and 13 with previous irradiation, underwent transplant. Conditioning regimens included a backbone of thiotepa, which was given either in a single cycle or in multiple sequential cycles. The 3-year post-transplant event-free survival rate in unirradiated versus previously irradiated children was 83% +/- 15% versus 20% +/- 12%, respectively (P = .04). One child who had never been exposed to radiotherapy died of toxicity; the other children received post-transplant radiotherapy and remained disease free. Nine previously irradiated children experienced 4 toxic deaths and 6 tumor recurrences (1 patient had both): An interval of <1 year between initial radiotherapy and myeloablative chemotherapy predicted a greater risk of toxic death (P = .02), whereas a history of meningeal metastases at diagnosis and a poor response to the initial rescue therapy predicted a greater risk of post-transplant recurrence (P = .03 and P = .08, respectively). CONCLUSIONS: Myeloablative doses of thiotepa-based chemotherapy and radiotherapy were able to cure most children who had radiotherapy-naive, chemoresponsive recurrences. Children who developed recurrences after craniospinal radiotherapy had poorer outcomes; however, cure was possible in those who had good prognostic features at presentation, chemoresponsive recurrences, and a long interval between initial radiotherapy and myeloablative chemotherapy.

Invasive diagnostic procedures for pulmonary infiltrates in pediatric hematopoietic stem cell transplant recipients.

To evaluate the role of BAL, CTB, and OLB in the management of pulmonary infiltrates in pediatric HSCT recipients, we conducted a retrospective review of clinical records of pediatric HSCT recipients. Data were analyzed using Chi-square for dichotomous and anova for continuous variables. Logistic regression was used to adjust confounding variables for diagnostic yield. Forty patients underwent 44 separate procedures. Infections were the prevailing cause of infiltrates with a positive diagnostic yield (96%). CTB and OLB were performed more often in patients with focal infiltrates compared with BAL (100%, 71% vs. 22%; p < 0.01). Adverse events were not significantly different across the three procedures. OLB more often yielded information that led to change in medical management (71% vs. 0%, 34%; p < 0.05) compared with CTB and BAL. Patients who had a positive diagnostic yield had no apparent survival advantage when compared with those in whom a procedure yielded no information. Logistic regression demonstrated that focal infiltrate was the only independently predictive variable for identifying a cause of pulmonary infiltrate. In conclusion, all three invasive diagnostic procedures were safe. Having a focal infiltrate was independently and significantly associated with having a positive diagnostic yield.

Obesity and outcome in pediatric acute lymphoblastic leukemia.

PURPOSE: To evaluate the effect of obesity (defined as a body mass index > 95th percentile for age and sex at diagnosis) on outcome of pediatric acute lymphoblastic leukemia (ALL). PATIENTS AND METHODS: We retrospectively analyzed data from 4,260 patients with newly diagnosed ALL enrolled from 1988 to 1995 onto five concurrent Children's Cancer Group studies. Results were verified in a second cohort of 1,733 patients enrolled onto a sixth study from 1996 to 2002. RESULTS: The 1988 to 1995 cohort included 343 obese and 3,971 nonobese patients. The 5-year event-free survival rate and risk of relapse in obese versus nonobese patients were 72% +/- 2.4% v 77% +/- 0.6% (P = .02) and 26 +/- 2.4 v 20 +/- 0.6 (P = .02), respectively. After adjusting for other prognostic variables, obesity's hazard ratios (HRs) of events and relapses were 1.36 (95% CI, 1.04 to 1.77; P = .021) and 1.29 (95% CI, 1.02 to 1.56; P = .04), respectively. The effect of obesity was prominent in the 1,003 patients > or = 10 years old at diagnosis; in this subset, obesity's adjusted HRs of events and relapses were 1.5 (95% CI, 1.1 to 2.1; P = .009) and 1.5 (95% CI, 1.2 to 2.1; P = .013), respectively. In a second cohort of 1,160 patients 10 years old, obesity's adjusted HRs of events and relapses were 1.42 (95% CI, 1.03 to 1.96; P = .032) and 1.65 (95% CI, 1.13 to 2.41; P = .009), respectively. The effect of obesity on outcome was unrelated to changes in chemotherapy doses, length of intervals between chemotherapy cycles, or incidence and severity of therapy-related toxicity. CONCLUSION: Obesity at diagnosis independently predicts likelihood of relapse and cure in preteenagers and adolescents with ALL.

Approaches to treatment for extraocular retinoblastoma: Children's Hospital Los Angeles experience.

Extraocular retinoblastoma is associated with a very poor outcome. At Children's Hospital Los Angeles, 10 of 207 patients with retinoblastoma had extraocular disease. Four patients with no histopathologic risk factors developed extraocular disease. All patients with direct extension into the central nervous system or with distant metastatic disease died. One of three patients with trilateral retinoblastoma and one patient with regional recurrence are alive after autologous bone marrow transplant. Patients with extraocular retinoblastoma who achieve remission may benefit from consolidation of their therapy with autologous bone marrow transplant.

Modeling minimal residual disease (MRD)-testing.

There is considerable effort to develop more sensitive methods to detect minimal residual disease (MRD) in bone marrow and blood samples of persons with cancer. Results of MRD-testing are used to predict clinical outcome and determine if more anti-cancer therapy is needed. Mathematical models were developed to assess factors affecting sensitivity and specificity of MRD-testing at diverse cancer cell prevalences. Modeling results and predictions were compared to results of large published studies.Accuracy of MRD-testing depends on cancer cell prevalence and distribution in the blood or bone marrow of the subject, sensitivity and specificity of the MRD-test and sample size. In subjects with low cancer cell prevalences (< or = 10(-4)) results of MRD testing are likely inaccurate. Increasingly sensitive MRD-tests are only marginally useful; the major obstacle to accuracy is inadequate sampling. Increasing sensitivity of methods to detect MRD is unlikely sufficient to increase accuracy of MRD-testing. In contrast, increased sampling (size and frequency) and assigning a high cut-off value (for example, > or = 10(-3)) to declare a MRD-test positive will increase sensitivity and specificity, respectively.