Rationale and design of the POLEM trial: avelumab plus fluoropyrimidine-based chemotherapy as adjuvant treatment for stage III mismatch repair deficient or POLE exonuclease domain... by Lau, D, Kalaitzaki, E, Church, DN, Pandha, H, Tomlinson, I, Annels, N, Gerlinger, M, Sclafani, F, Smith, G, Begum, R, Crux, R, Gillbanks, A, Wordsworth, S, Chau, I, Starling, N, Cunningham, D, Dhillon, T