1983PD_PRComprehensive genomic profiling (CGP) of carcinoma of unknown primary origin (CUP): Retrospective molecular classification of potentially eligible patients (pts) for targeted or immunotherapy treatment (tx) using the prospective CUPISCO trial’s criteria

Abstract Background Standard CUP therapy has not changed for decades. CUPISCO (NCT03498521) is an ongoing randomised prospective trial using CGP to assign CUP pts to individualised targeted or immunotherapy arms (molecularly guided therapy; MGT). Methods Archival tissue from 303 centrally reviewed undifferentiated- and adeno-CUP cases in the FoundationCore™ database underwent hybrid capture-based CGP (FoundationOne® CDx). Microsatellite instability (MSI), tumour mutational burden (TMB) and genomic loss of heterozygosity (gLOH) were calculated (Frampton Nat Biotechnol 2013; Swisher Lancet Oncol; Chambers Genome Med 2017). PD-L1 expression was measured by DAKO 22C3 immunohistochemistry. Pts were classified by whether CGP results could have informed assignment to CUPISCO arms; TTF-1+, CK7–/CK20+/CDX2+ or TMPRSS2:ERG+ cases were excluded. Results The sex ratio was 1:1; median age was 67 yrs (range 22–89+). CGP revealed 96 pts (32%) matched to a CUPISCO arm (Table). Table . 1983PD_PR CUPISCO arm % Genomic alterations Alectinib 0.66 Vismodegib 1.32 Ipatasertib 8.25 Olaparib 5.61 Erlotinib + bevacizumab 2.31 Vemurafenib + cobimetinib 2.97 Subcutaneous trastuzumab + pertuzumab + chemo 9.24 Atezolizumab 9.24 Entrectinib (in development) 0.33 Mean TMB was 8 mut/Mb; 23% had ≥10 (low), 12%, ≥16 (int) and 9%, ≥20 (high). 3 (1%) had high MSI and 20%, gLOH ≥16. 42 (14%) had high PD-L1 (tumour proportion score ≥50%). Key genomic alterations included HER2 (7%), PIK3CA, NF1 (6% each), NF2 (5%), BRAF, PTEN, FGFR2, EGFR, MET (all 4%), CDK6 (3%), FBXW7 and CDK4 (2% each). Key gene fusions involved ALK, RET and ROS1 (all 1%). KRAS was mutated in 27%; 6% had G12C alterations. Of the 23 assessable high TMB cases, 8 (35%) had a tobacco and 5 (22%) a UV light or mismatch repair mutational signature. 20% of cases harboured a putative cancer-associated germline DNA mutation. Conclusions 32% of CUP pts would have been potentially eligible for MGT in CUPISCO. Future studies including additional biomarkers, such as PD-L1–positivity and gLOH, may identify a greater proportion of CUP pts potentially benefitting from individualised treatment. Editorial acknowledgement Support for third-party editing assistance for this abstract, furnished by Daniel Clyde, PhD, of Health Interactions, was provided by F. Hoffmann-La Roche Ltd, Basel, Switzerland. Legal entity responsible for the study F. Hoffmann-La Roche Ltd. Funding F. Hoffmann-La Roche Ltd. Disclosure J.S. Ross: Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc.; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. E.S. Sokol: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. H. Moch: Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: F. Hoffmann-La Roche Ltd ; Advisory / Consultancy, Travel / Accommodation / Expenses: Definiens AG; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. L. Mileshkin: Travel / Accommodation / Expenses: F. Hoffmann-La Roche Ltd; Travel / Accommodation / Expenses: Beigene; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. G. Baciarello: Honoraria (self), Travel / Accommodation / Expenses: F. Hoffmann-La Roche Ltd; Honoraria (self), Travel / Accommodation / Expenses: Astellas; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Janssen; Honoraria (self), Travel / Accommodation / Expenses: Ipsen; Honoraria (self): Amgen; Travel / Accommodation / Expenses: AstraZeneca; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd; Advisory / Consultancy, Travel / Accommodation / Expenses: Sanofi. F. Losa: Advisory / Consultancy, Speaker Bureau / Expert testimony, Research grant / Funding (institution), Travel / Accommodation / Expenses: F. Hoffmann-La Roche Ltd; Advisory / Consultancy, Speaker Bureau / Expert testimony: Sanofi; Advisory / Consultancy, Research grant / Funding (institution): Amgen; Advisory / Consultancy, Research grant / Funding (institution), Travel / Accommodation / Expenses: Merck; Advisory / Consultancy: Servier; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. A. Beringer: Full / Part-time employment, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. M. Thomas: Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. S. Foser: Leadership role, Shareholder / Stockholder / Stock options, Full / Part-time employment, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. J. Elvin: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. N. Danziger: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. N. Ngo: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. J.Y. Tse: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. K. Killian: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Full / Part-time employment, Special Volunteer: National Cancer Institute; Shareholder / Stockholder / Stock options, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. D.X. Jin: Shareholder / Stockholder / Stock options, Full / Part-time employment: Foundation Medicine, Inc; Shareholder / Stockholder / Stock options, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd. L.M. Gay: Full / Part-time employment, Current: Ellem Consulting; Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd; Full / Part-time employment, Previous: Foundation Medicine, Inc. A. Kramer: Honoraria (self), Honoraria (institution), Advisory / Consultancy, Travel / Accommodation / Expenses, Non-remunerated activity/ies, Support for third-party editing assistance: F. Hoffmann-La Roche Ltd; Honoraria (self), Advisory / Consultancy, Travel / Accommodation / Expenses: Daiichi Sankyo; Honoraria (self), Advisory / Consultancy: Abbvie; Honoraria (institution), Research grant / Funding (institution): Bayer; Advisory / Consultancy: BMS; Travel / Accommodation / Expenses: Celgene; Research grant / Funding (institution): Merck.