Berger, Michael

Abstract PURPOSE: A subset of pediatric, adolescent and young adult (AYA) gliomas are located in the brainstem, eloquent locations, or present with diffuse/leptomeningeal disease, and are associated with high risk and low yield of biopsy. At the same time, accurate molecular diagnosis is necessary to direct optimal therapy. In such cases, analysis of cell free DNA (cfDNA) form cerebral spinal fluid (CSF) may represent a diagnostic alternative to biopsy. METHODS: We investigated the utility of CSF cfDNA sequencing through a stepwise approach, using clinically validated, targeted molecular assays. Testing was performed using a broad hybrid capture next generation sequencing assay (MSK-IMPACT) and subsequent targeted digital droplet PCR in a subset of cases. RESULTS: We analyzed 17 CSF samples from 17 pediatric (n=6) and AYA (n=11) glioma patients with primary or recurrent disease. Thirteen had tumors located within the brainstem, and four had leptomeningeal involvement. Somatic alterations were detected in 12/17 samples (71%). In 3/4 patients with leptomeningeal involvement, cfDNA testing revealed a BRAF fusion consistent with the diagnosis of diffuse leptomeningeal glioneuronal tumor (DLGNT). Among the 13 patients with brainstem involvement, four had somatic H3 K27M mutations, three had IDH mutations, and one had TP53 and ATRX mutations; five patients had no detectable mutations. CONCLUSION: In our analysis, we found that established glioma hotspot mutations were able to be detected within the CSF. We propose that in patients for whom tissue biopsy is high risk, not feasible, or tissue was nondiagnostic, CSF cfDNA sequencing has a substantial diagnostic yield and should be considered as a valuable novel diagnostic tool. Ongoing research is aiming to further increase the sensitivity of cfDNA testing, especially in patients with very low levels of CSF cfDNA.

Abstract HER2 mutations are infrequent genomic events in biliary tract cancers (BTCs). Neratinib, an irreversible, pan-HER, oral tyrosine kinase inhibitor, interferes with constitutive receptor kinase activation and has activity in HER2-mutant tumours. SUMMIT is an open-label, single-arm, multi-cohort, phase 2, ‘basket’ trial of neratinib in patients with solid tumours harbouring oncogenic HER2 somatic mutations (NCT01953926). The primary objective of the BTC cohort was objective response rate (ORR). Among 25 treatment-refractory patients (11 cholangiocarcinoma, 10 gallbladder, 4 ampullary cancers), the ORR was 16%. The most common HER2 mutations were S310F (n = 11; 48%) and V777L (n = 4; 17%). Outcomes appeared worse for ampullary tumours or those with co-occurring oncogenic TP53 and CDKN2A alterations. Loss of amplified HER2 S310F and acquisition of multiple previously undetected oncogenic co-mutations were identified at progression in one responder. Neratinib demonstrated anti-tumour activity in patients with refractory BTC harbouring HER2 mutations. Future studies of rational combinations are warranted.

Abstract Introduction: AI-induced joint symptoms negatively impact drug adherence and quality of life. Based on observations that n-3 polyunsaturated fatty acids (PUFAs) have anti-inflammatory effects and that the mechanism of AI-induced joint symptoms may be partly due to inflammation, we hypothesized that women taking more n-3 PUFAs are less likely to develop AI-induced joint symptoms. Methods: We conducted a randomized, double-blind, placebo-controlled study comparing n-3 PUFA vs placebo in postmenopausal breast cancer patients starting adjuvant AIs. Participants were randomized to n-3 supplements [2.58 g eicosapentaenoic acid + 1.74 g docosahexaenoic acid/day; Marine Nutriceuticals, Mt. Bethel, PA] vs matched placebo for 24 weeks (wks). Primary endpoints was feasibility; secondary outcomes were self-reported symptoms as assessed by the Brief Pain Inventory short form (BPI-SF), Functional Assessment of Cancer Treatment, Breast & Endocrine Symptoms (FACTB-ES), and Stanford's Health Assessment and Disability Index (HAQ) at baseline prior to AI receipt, 12 and 24 wks. Compliance and toxicity were evaluated monthly. Serial peripheral blood n-3 PUFA levels and inflammatory cytokines (IL-6, TNFR2, IL-17) were drawn. MRI of hands/wrists was performed in selected patients using a 3 Tesla dedicated wrist coil at baseline and treatment end. Results: Forty-four women were enrolled and randomized to study drug; 42 received ≥1 cycle (4 wks) of treatment; 36 had ≥1 post treatment evaluation at wk 12 or 24. Median age was 59.5 (range 43-76); history of prior taxane (n=15, 34%). The two groups’ baseline characteristics were similar. Overall, 93% and 88% of patients took >80% of the placebo and n-3 PUFA doses, respectively. Baseline erythrocyte n-3 PUFA was similar for both groups (6.6% ± 1.6%, 7.2% ±1.9%, p=0.20), but higher in the n-3 PUFA arm by wk 24 (6.5%±1.0% vs 15.0%±3.3%, p<0.001). Most toxicities were grade 1; the n-3 PUFA arm had only 1 (2.5%) grade 3 toxicity (diarrhea). The n-3 PUFA arm reported lower mean BPI-SF scores after treatment [(-.0.28/ -0.25 at week 12/24); but not statistically significant compared to placebo (p=0.494 and 0.601)]. Based on BPI-SF, the n-3 PUFA arm reported less interference of pain symptoms compared to placebo at 12 weeks (-.72, p=0.08). This arm also had a decreased walking, activity and working (WAW) score on BPI-SF at 12 weeks (-.81 p=0.05), and reported significantly greater pain relief from medications at 12 (p=0.043) and 24 weeks (p=0.011). Both arms had similar baseline and wk 24 serum IL-6 levels; levels decreased from baseline to wk 24 in the n-3 PUFA arm (-0.54±0.25, p=0.048). There was a non-significant trend (p= 0.2) toward decreased wrist inflammation by MRI imaging at 24 wks in the n-3 PUFA arm. Conclusions: This is the first randomized pilot study to show that n-3 PUFA supplementation to prevent AI-induced joint symptoms is feasible and well tolerated. There is preliminary evidence that this intervention may help reduce the burden of AI-induced arthralgias. OSU Study #11022; ClinicalTrials.gov Identifier: NCT01478477. Grants from the National Cancer Institute (CA037447-26) to the Alliance for Clinical Trials in Oncology supported this pilot study. Citation Format: Maryam B Lustberg, Tonya Orchard, Xueliang Pan, Raquel Reinbolt, Amanda Logan, Joanne Lester, Rachel M Layman, Erin Macrae, Ewa Mrozek, Bhuvaneswari Ramaswamy, Robert Wesolowski, Michael Berger, Michael Knopp, Charles Loprinzi, Charles L Shapiro, Lisa Yee. Prevention of aromatase Inhibitor (AI)-induced joint symptoms with omega-3 fatty acid supplementation: A randomized placebo-controlled pilot study [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P1-09-03.