Assessment of the treatment approach and survival outcomes in a modern cohort of patients with atypical teratoid rhabdoid tumors using the National Cancer Database.

BACKGROUND: Atypical teratoid rhabdoid tumors (ATRTs) are rare brain tumors that occur primarily in children under the age of 3 years. This report evaluates the treatment approach and survival outcomes in a large cohort of patients treated in the United States. METHODS: Using the National Cancer Database, the analysis included all ATRT patients aged 0 to 18 years who were diagnosed between 2004 and 2012 and had complete treatment data. RESULTS: Three hundred sixty-one ATRT patients were evaluated. The 5-year overall survival (OS) rate was 29.9%, and it was significantly lower for children who were less than 3 years old (5-year OS, 27.7%) versus those who were 3 years old or older (5-year OS, 37.5%; P < .001). The best outcome was seen for patients with localized disease who received trimodality therapy (surgery, chemotherapy, and radiation therapy [RT]) with a 5-year OS rate of 46.8%. The utilization of trimodality therapy significantly increased during the study period (27.7% in 2004-2008 vs 45.1% in 2009-2012; P < .01), largely because of the increased use of RT. In a multivariate analysis, treatment that did not utilize trimodality therapy was associated with significantly worse OS (hazard ratio, 2.52; 95% confidence interval (1.82-3.51). Children aged 0 to 2 years were significantly less likely to receive trimodality therapy because of decreased utilization of RT in this age group. CONCLUSIONS: The use of trimodality therapy significantly increased during the study period and was associated with improved outcomes. For patients with localized disease who received trimodality therapy, the OS rate at 5 years approached 50%. However, further research into the optimal management of children less than 3 years old is needed because of their significantly worse OS in comparison with older children. Cancer 2017;123:682-687. © 2016 American Cancer Society.

Profiling pathway-specific novel therapeutics in preclinical assessment for central nervous system atypical teratoid rhabdoid tumors (CNS ATRT): favorable activity of targeting EGFR- ErbB2 signaling with lapatinib.

Despite intensifying multimodal treatments, children with central nervous system atypical teratoid/rhabdoid tumor (CNS ATRT) continue to endure unacceptably high mortality rates. At present, concerted efforts are focusing on understanding the characteristic INI1 mutation and its implications for the growth and survival of these tumors. Additionally, pharmaceutical pipeline libraries constitute a significant source of potential agents that can be taken to clinical trials in a timely manner. However, this process requires efficient target validation and relevant preclinical studies. As an initial screening approach, a panel of 129 small molecule inhibitors from multiple pharmaceutical pipeline libraries was tested against three ATRT cell lines by in vitro cytotoxicity assays. Based on these data, agents that have strong activity and corresponding susceptible cellular pathways were identified. Target modulation, antibody array analysis, drug combination and in vivo xenograft studies were performed on one of the pathway inhibitors found in this screening. Approximately 20% of agents in the library showed activity with IC(50) values of 1 µM or less and many showed IC(50) values less than 0.05 µM. Intra cell line variability was also noted among some of the drugs. However, it was determined that agents capable of affecting pathways constituting ErbB2, mTOR, proteasomes, Hsp90, Polo like kinases and Aurora kinases were universally effective against the three ATRT cell lines. The first target selected for further analysis, the inhibition of ErbB2-EGFR pathway by the small molecule inhibitor lapatinib, indicated inhibition of cell migration properties and the initiation of apoptosis. Synergy between lapatinib and IGF-IR inhibition was also demonstrated by combination index (CI) values. Xenograft studies showed effective antitumor activity of lapatinib in vivo. We present an experimental approach to identifying agents and drug combinations for future clinical trials and provide evidence for the potential of lapatinib as an effective agent in the context of the biology and heterogeneity of its targets in ATRT.