Sheraz Yaqub, Morten Valberg, Bjørn Atle Bjørnbeth, Jon-Helge Angelsen, Kristoffer Watten Brudvik, Ina Andrassy Eilertsen, Richard Fristedt, Claus Wilki Fristrup, Stefan Gilg, Oskar Hemmingsson, Bengt Isaksson, Ingebjørg Soterud Juel, Anders Riegels Knudsen, Peter Nørgaard Larsen, Kim Erlend Mortensen, Inge Christoffer Olsen, Per Sandström, Oddvar Mathias Sandvik, Ernesto Sparrelid, Helena Taflin, Ragnhild A Lothe, Kjetil Taskén, ASAC Study Group
Adjuvant aspirin did not improve disease-free survival and was associated with lower overall survival and more serious adverse events. These findings do not support routine use of aspirin after curative-intent treatment of colorectal cancer liver metastases.
BACKGROUND: Colorectal cancer frequently metastasises to the liver. Recurrence after curative-intent treatment of colorectal cancer liver metastases is common. Aspirin has shown preventive and antitumour effects in colorectal cancer, but its role after treatment of metastatic disease is uncertain. We aimed to establish whether adjuvant aspirin improves disease-free survival after curative-intent treatment of colorectal cancer liver metastases.
METHODS: In this phase 3, randomised, double-blind, placebo-controlled trial conducted at 14 centres in Norway, Sweden, and Denmark, patients who had undergone curative-intent treatment for colorectal cancer liver metastases were randomly assigned (1:1), stratified by study site using a centrally generated computerised sequence with variable block sizes, to aspirin 160 mg per day or matching placebo for up to 3 years or until recurrence, death, or treatment discontinuation. The primary outcome was disease-free survival in the full analysis set, comprising all patients who initiated study treatment. The trial is completed and this is the final analysis. This trial is registered with ClinicalTrials.gov, NCT03326791, and EudraCT, 2014-003601-15.
FINDINGS: Between Dec 15, 2017, and Jan 27, 2022, 466 patients were randomly assigned, of whom 428 initiated study treatment and were included in the full analysis set (217 assigned aspirin and 211 assigned placebo); 272 (64%) were male, 156 (36%) were female, and the mean age was 62·2 years. 269 disease-free survival events occurred (138 in the aspirin group and 131 in the placebo group). Aspirin did not improve disease-free survival (hazard ratio [HR] for recurrence or death 1·08 [95·44% CI 0·85-1·38]; p=0·58). Median disease-free survival was 1·13 years (95·44% CI 0·92-1·44) with aspirin and 1·40 years (1·11-1·69) with placebo. Overall survival at 36 months was 76% (95% CI 69·4-82·7) with aspirin and 85% (79·5-90·8) with placebo (HR for death 1·64 [95% CI 1·01-2·65]; p=0·045). Time to recurrence did not differ between groups (adjusted cause-specific HR 1·06 [95% CI 0·83-1·35]; p=0·64). 24 serious adverse events occurred in 17 (8%) of 217 patients in the aspirin group and five serious adverse events occurred in four (2%) of 211 patients in the placebo group. Clinically relevant adverse events and serious adverse events that occurred more commonly in the aspirin group than in the placebo group were myocardial infarction (two vs 0), epistaxis (four vs 0), duodenal ulcer (two vs 0), and cerebral haemorrhage (two vs 0). There were no treatment-related deaths.
INTERPRETATION: Adjuvant aspirin did not improve disease-free survival and was associated with lower overall survival and more serious adverse events. These findings do not support routine use of aspirin after curative-intent treatment of colorectal cancer liver metastases.
FUNDING: Research Council of Norway, Norwegian Cancer Society, Therapy Research in the Specialist Health Services Norway, and Oslo University Hospital Fondsstiftelsen.