Real World Data on Adjuvant Chemotherapy in Stage II Colorectal Cancer: Risk Factors and Benefits |Biomedgrid

Adjuvant chemotherapy (ACh) benefits in stage II colorectal cancer (CRC) is still unclear. Risk factors (RF) as perineural (PNI) or lymphovascular (LVI) infiltrate in biopsy, T4 or less than 12 lymph nodes (LN) resected during surgery has associated with recurrence. We retrospectively evaluated Ach benefits in stage II CRC patients. This retrospective analysis collected information of CRC patients who were treated at University of Chile Clinical Hospital between 2011-2018 and had histological diagnosis of T3-4N0 colon adenocarcinoma. Clinical, surgical, histological variables, and RF were recorded. Disease-free survival (DFS) was compared in patients who underwent ACh with patients who were observed. Of 91 patients, 51% received Ach and 49% observation. Median age was 60± 13 years. ACh were FOLFOX, CAPOX, capecitabine or FU/LV in 70%, 17%, 11%, and 2% of patients, respectively. DFS was 45 and 36 months in ACh and observation groups (p=0,277). RF were present in 62%, and of these 73% received ACh and 27% observation. There were no association of T4 stage, PNI and/or LVI with improve DFS and response to ACh. Recurrence was presented in 12,6% of patients and 75% of this presented one or more RF. In this retrospective cohort, ACh did not improve DFS compared to observation only. In our study, 25% of recurrences are in patients without RF, therefore it is necessary to improve strategies to predict recurrences and response to ACh. Further studies should evaluate other elements to optimize the decision to administer ACh in these patients, such as microsatellite instability and circulating DNA.