eprintid: 10131513 rev_number: 16 eprint_status: archive userid: 608 dir: disk0/10/13/15/13 datestamp: 2021-07-20 11:09:52 lastmod: 2021-12-20 23:47:52 status_changed: 2021-07-20 11:09:52 type: article metadata_visibility: show creators_name: Ten Hoorn, S creators_name: Sommeijer, DW creators_name: Elliott, F creators_name: Fisher, D creators_name: de Back, TR creators_name: Trinh, A creators_name: Koens, L creators_name: Maughan, T creators_name: Seligmann, J creators_name: Seymour, MT creators_name: Quirke, P creators_name: Adams, R creators_name: Richman, SD creators_name: Punt, CJA creators_name: Vermeulen, L title: Molecular subtype-specific efficacy of anti-EGFR therapy in colorectal cancer is dependent on the chemotherapy backbone ispublished: inpress divisions: UCL divisions: B02 divisions: D65 divisions: J38 keywords: Chemotherapy, Colorectal cancer, Metastasis note: This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. abstract: BACKGROUND: Patient selection for addition of anti-EGFR therapy to chemotherapy for patients with RAS and BRAF wildtype metastatic colorectal cancer can still be optimised. Here we investigate the effect of anti-EGFR therapy on survival in different consensus molecular subtypes (CMSs) and stratified by primary tumour location. METHODS: Retrospective analyses, using the immunohistochemistry-based CMS classifier, were performed in the COIN (first-line oxaliplatin backbone with or without cetuximab) and PICCOLO trial (second-line irinotecan with or without panitumumab). Tumour tissue was available for 323 patients (20%) and 349 (41%), respectively. RESULTS: When using an irinotecan backbone, anti-EGFR therapy is effective in both CMS2/3 and CMS4 in left-sided primary tumours (progression-free survival (PFS): HR 0.44, 95% CI 0.26-0.75, P = 0.003 and HR 0.12, 95% CI 0.04-0.36, P < 0.001, respectively) and in CMS4 right-sided tumours (PFS HR 0.17, 95% CI 0.04-0.71, P = 0.02). Efficacy using an oxaliplatin backbone was restricted to left-sided CMS2/3 tumours (HR 0.57, 95% CI 0.36-0.96, P = 0.034). CONCLUSIONS: The subtype-specific efficacy of anti-EGFR therapy is dependent on the chemotherapy backbone. This may provide the possibility of subtype-specific treatment strategies for a more optimal use of anti-EGFR therapy. date: 2021-07-12 date_type: published official_url: https://doi.org/10.1038/s41416-021-01477-9 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1877399 doi: 10.1038/s41416-021-01477-9 pii: 10.1038/s41416-021-01477-9 lyricists_name: Fisher, David lyricists_id: DFISH32 actors_name: Flynn, Bernadette actors_id: BFFLY94 actors_role: owner full_text_status: public publication: British Journal of Cancer event_location: England citation: Ten Hoorn, S; Sommeijer, DW; Elliott, F; Fisher, D; de Back, TR; Trinh, A; Koens, L; ... Vermeulen, L; + view all <#> Ten Hoorn, S; Sommeijer, DW; Elliott, F; Fisher, D; de Back, TR; Trinh, A; Koens, L; Maughan, T; Seligmann, J; Seymour, MT; Quirke, P; Adams, R; Richman, SD; Punt, CJA; Vermeulen, L; - view fewer <#> (2021) Molecular subtype-specific efficacy of anti-EGFR therapy in colorectal cancer is dependent on the chemotherapy backbone. British Journal of Cancer 10.1038/s41416-021-01477-9 <https://doi.org/10.1038/s41416-021-01477-9>. (In press). Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10131513/1/s41416-021-01477-9.pdf