Abstract 5384: The Angiosarcoma Project: Generating the genomic landscape of an exceedingly rare cancer through a nationwide patient-driven initiative

Angiosarcoma (AS) is an exceedingly rare soft tissue sarcoma, with an incidence of 300 cases/yr and a 5-year disease-specific survival of 30%. The low incidence has impeded large-scale research efforts that may lead to improved clinical outcomes. To address this, we launched a nationwide clinical-genomics study in order to empower patients to accelerate research by sharing their normal and tumor samples and clinical information remotely. Patients can access the study through an online portal (ASCproject.org). Enrolled patients are mailed saliva and blood draw kits. The study team obtains medical records and stored FFPE tumor samples. All received FFPE samples are examined by an expert pathologist to confirm a diagnosis of angiosarcoma. In order to validate that our processes would enable the generation of a robust dataset from tissues acquired from multiple institutions, we sought to characterize previously described genes known to be altered in angiosarcoma (e.g., TP53, NF1, KDR, BRCA2, MET, ARID1A, POT1, BRCA1, ASXL1, KDM6A, BRAF, SETD2, PTPRB, NRAS). A total of 251 patients have enrolled since the project launched in March of 2017. Primary locations of AS are primary breast 59 (25%), breast with prior radiation 45 (19%), head/face/neck/scalp 52 (22%), bone/limb 26 (11%), abdomen 5 (2%), heart 5 (2%), lung 2 (1%), liver 1 (1%), lymph 1 (0.4%), multiple locations 25 (11%), and other locations 12 (5%); 107 (52%) reported being disease free at the time of enrollment. To date, we have received 129 saliva kits, 106 medical records, 19 blood samples, and 36 tissue samples. Whole-exome sequencing (WES) was performed on 21 FFPE/saliva matched pairs with a goal mean target coverage of 150x for tumors. Ultra-low pass whole-genome sequencing (0.1x) was performed on cell free DNA (cfDNA) from plasma in order to determine tumor fraction. Of 10 cfDNA samples sequenced, 4 samples met criteria to perform WES. Additionally, transcriptome sequencing was performed on 9 FFPE samples. Sequence data processing and analysis has been completed on the first 10 samples and is in progress for the subsequent samples. Alterations were detected in genes previously described to be affected in angiosarcoma. Recurrent mutations in TP53 were detected in 50% (5/10) of analyzed samples, comprising 3 missense mutations, 1 frameshift deletion, and 1 frameshift insertion. Alterations were seen in at least one sample in all other genes selected for this initial analysis. This initiative demonstrates the feasibility of studying tissues from geographically dispersed patients and serves as proof of concept that patient-driven genomics efforts can democratize research for exceedingly rare cancers. Enrollment is still in progress, and additional samples will be sequenced and analyzed at scale. The data generated from these studies will be deposited into the public domain in six-month intervals. Citation Format: Michael Dunphy, Esha Jain, Elana Anastasio, Mary McGillicuddy, Rachel Stoddard, Beena Thomas, Sara Balch, Kristin Anderka, Katie Larkin, Niall Lennon, Yen-Lin Chen, Andrew Zimmer, Esme O. Baker, Simone Maiwald, Jen Hendrey Lapan, Jason Hornick, Chandrajit Raut, George Demetri, Eric Lander, Todd Golub, Nikhil Wagle, Corrie Painter. The Angiosarcoma Project: Generating the genomic landscape of an exceedingly rare cancer through a nationwide patient-driven initiative [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5384.