Faculty Bibliography

Sirolimus has activity against acute lymphoblastic leukemia (ALL) in xenograft models and efficacy in preventing acute graft-versus-host disease (aGVHD). We tested whether addition of sirolimus to GVHD prophylaxis of children with ALL would decrease aGVHD and relapse. Patients were randomized to tacrolimus/methotrexate (standard) or tacrolimus/methotrexate/sirolimus (experimental). The study met futility rules for survival after enrolling 146 of 259 patients. Rate of Grade 2-4 aGVHD was 31% vs 18% (standard vs experimental, P = .04), however, grade 3-4 aGVHD was not different (13% vs 10%, P = .28). Rates of veno-occlusive disease (VOD) and thrombotic microangiopathy (TMA) were lower in the nonsirolimus arm (9% vs 21% VOD, P = .05; 1% vs 10% TMA, P = .06). At 2 years, event free survival (EFS) and overall survival (OS) were 56% vs 46%, and 65% vs 55% (standard vs experimental), respectively (P = .28 and .23). Multivariate analysis showed increased relapse risk in children with >/=0.1% minimal residual disease (MRD) pretransplant, and decreased risk in patients with grades 1-3 aGVHD (P = .04). Grades 1-3 aGVHD were associated with improved EFS (P = .02), whereas grade 4 aGVHD and extramedullary disease at diagnosis led to inferior OS. Although addition of sirolimus decreased aGVHD, survival was not improved. This study is registered with ClinicalTrials.gov as #NCT00382109.

A MESSAGE FROM ASCO'S PRESIDENT: Since its founding in 1964, the American Society of Clinical Oncology (ASCO) has been committed to improving cancer outcomes through research and the delivery of quality care. Research is the bedrock of discovering better treatments--providing hope to the millions of individuals who face a cancer diagnosis each year. The studies featured in "Clinical Cancer Advances 2013: Annual Report on Progress Against Cancer From the American Society of Clinical Oncology" represent the invaluable contributions of thousands of patients who participate in clinical trials and the scientists who conduct basic and clinical research. The insights described in this report, such as how cancers hide from the immune system and why cancers may become resistant to targeted drugs, enable us to envision a future in which cancer will be even more controllable and preventable. The scientific process is thoughtful, deliberate, and sometimes slow, but each advance, while helping patients, now also points toward new research questions and unexplored opportunities. Both dramatic and subtle breakthroughs occur so that progress against cancer typically builds over many years. Success requires vision, persistence, and a long-term commitment to supporting cancer research and training. Our nation's longstanding investment in federally funded cancer research has contributed significantly to a growing array of effective new treatments and a much deeper understanding of the drivers of cancer. But despite this progress, our position as a world leader in advancing medical knowledge and our ability to attract the most promising and talented investigators are now threatened by an acute problem: Federal funding for cancer research has steadily eroded over the past decade, and only 15% of the ever-shrinking budget is actually spent on clinical trials. This dismal reality threatens the pace of progress against cancer and undermines our ability to address the continuing needs of our patients. Despite this extremely challenging economic environment, we continue to make progress. Maintaining and accelerating that progress require that we keep our eyes on the future and pursue a path that builds on the stunning successes of the past. We must continue to show our policymakers the successes in cancer survival and quality of life (QOL) they have enabled, emphasizing the need to sustain our national investment in the remarkably productive US cancer research enterprise. We must also look to innovative methods for transforming how we care for-and learn from-patients with cancer. Consider, for example, that fewer than 5% of adult patients with cancer currently participate in clinical trials. What if we were able to draw lessons from the other 95%? This possibility led ASCO this year to launch CancerLinQ, a groundbreaking health information technology initiative that will provide physicians with access to vast quantities of clinical data about real-world patients and help achieve higher quality, higher value cancer care. As you read the following pages, I hope our collective progress against cancer over the past year inspires you. More importantly, I hope the pride you feel motivates you to help us accelerate the pace of scientific advancement. Clifford A. Hudis, MD, FACP President American Society of Clinical Oncology.

Recent genomic profiling of childhood acute lymphoblastic leukemia (ALL) identified a high-risk subtype with an expression signature resembling that of Philadelphia chromosome-positive ALL and poor prognosis (Ph-like ALL). However, the role of inherited genetic variation in Ph-like ALL pathogenesis remains unknown. In a genome-wide association study (GWAS) of 511 ALL cases and 6,661 non-ALL controls, we identified a susceptibility locus for Ph-like ALL (GATA3, rs3824662; P = 2.17 x 10(-14), odds ratio (OR) = 3.85 for Ph-like ALL versus non-ALL; P = 1.05 x 10(-8), OR = 3.25 for Ph-like ALL versus non-Ph-like ALL), with independent validation. The rs3824662 risk allele was associated with somatic lesions underlying Ph-like ALL (CRLF2 rearrangement, JAK gene mutation and IKZF1 deletion) and with variation in GATA3 expression. Finally, genotype at the GATA3 SNP was also associated with early treatment response and risk of ALL relapse. Our results provide insights into interactions between inherited and somatic variants and their role in ALL pathogenesis and prognosis.

Background B cells are selected at multiple developmental checkpoints for an intermediate level of (pre-) B cell receptor (BCR) signaling strength: either insufficient or hyperactive signaling (e.g. from an autoreactive BCR) results in cell death. Acute lymphoblastic leukemia (ALL) is the most frequent type of cancer in children and typically arises from pre-B cells, a large fraction of which are autoreactive. In ~25% of patients, ALL is driven by an oncogenic tyrosine kinase (e.g. BCR-ABL1 in Ph+ ALL) and defines the ALL subgroup with the worst clinical outcome. Ph+ ALL cells invariably develop resistance against tyrosine kinase inhibitors (TKI). Here we tested the hypothesis that inherent mechanisms of negative selection to eliminate autoreactive clones with hyperactive pre-BCR signaling are still active in transformed pre-B cells and identified a potential therapeutic target for ALL patients. Results The BCR-ABL1 oncogene mimics a constitutively active pre-BCR and an incremental increase of pre-BCR downstream signaling (ITAM overexpression) was indeed sufficient to induce cell death in Ph+ ALL, but not in normal pre-B cells with low baseline signaling strength. TKI-treatment, while designed to kill leukemia cells, seemingly paradoxically rescued Ph+ ALL cells in this experimental setting. Patient-derived Ph+ ALL cells differ from normal pre-B cells by expression of high levels of ITIM containing inhibitory receptors including PECAM1, CD300A and LAIR1. However, ITAM containing activation receptors like CD79B was absent on the cell surface, and there was point or frame-shift mutation for both CD79A and CD79B. Importantly, high expression levels of ITIM-receptors are predictive of poor outcome in two clinical trials. In the COG trial (P9906; n=207) for children high-risk ALL, mRNA levels of PECAM1, CD300A and LAIR1 at diagnosis positively correlated with early minimal residual disease (MRD) findings on day 29 (p<0.0005), and negatively correlated with overall survival (OS) rate (p<0.02) or rela!

PURPOSE: Five-year overall survival (OS) for children with B-cell precursor acute lymphoblastic leukemia (B-ALL) exceeds 90% with risk-adapted therapy. Age, initial WBC count, genetic aberrations, and minimal residual disease (MRD) are used for risk stratification. Intrachromosomal amplification of a region of chromosome 21 (iAMP21; three or more extra copies of RUNX1 on an abnormal chromosome 21) is a recently identified recurrent genomic lesion associated with inferior outcome in some studies. We investigated the impact of iAMP21 in a large cohort treated in contemporary Children's Oncology Group (COG) ALL trials. PATIENTS AND METHODS: Fluorescent in situ hybridization for specific genetic aberrations was required at diagnosis. MRD was measured by flow cytometry at end induction. Outcome was measured as event-free survival (EFS) and OS. RESULTS: iAMP21 was found in 158 (2%) of 7,793 patients with B-ALL age >/= 1 year; 74 (1.5%) of 5,057 standard-risk (SR) patients, and 84 (3.1%) of 2,736 high-risk (HR) patients. iAMP21 was associated with age >/= 10 years, WBC less than 50,000/muL, female sex, and detectable MRD at day 29. Four-year EFS and OS were significantly worse for patients with iAMP21 and SR B-ALL, but iAMP21 was not a statistically significant prognostic factor in HR patients. There was no interaction between MRD and iAMP21. Among SR patients, day 29 MRD >/= 0.01% and iAMP21 were associated with the poorest EFS and OS; absence of both was associated with the best outcome. CONCLUSION: iAMP21 is associated with inferior outcome in pediatric B-ALL, particularly SR patients who require more intensive therapy and are now treated on HR COG ALL protocols.