Genetic Variants in Predicting Treatment Outcomes in Colorectal Cancer
Posted: Friday, March 1, 2019
A presentation at the 2019 Gastrointestinal Cancers Symposium in San Francisco (Abstract 566) suggested that single nucleotide polymorphisms (SNP) in the telomerase complex may help predict first-line treatment outcomes in patients with metastatic colorectal cancer. Francesca Battaglin, MD, of the Instituto Oncologico Veneto, Padova, Italy, and colleagues suggest that these genetic variants may have both a predictive and prognostic value in this patient population.
The authors analyzed the impact of 21 selected SNPs within 13 genes on genomic DNA from 451 patients with metastatic colorectal cancer; they used data from two independent phase III trials: TRIBE and FIRE-3. In the TRIBE study, patients treated with bevacizumab and FOLFIRI (leucovorin, fluorouracil, and irinotecan) served as a discovery cohort (n = 215). In the FIRE-3 trial, patients treated with bevacizumab/FOLFIRI served as the validation cohort (n = 107) and those treated with cetuximab/FOLFIRI served as the control (n = 129).
Patients in the discovery cohort carrying any A allele of TERT rs2075786 achieved longer median progression-free (P = .021) and overall survival (P = .005) than did those carrying the G/G genotype. Similarly, patients carrying any T allele of CLPTM1L rs401681 had better survival than did those with the C/C genotype (P = .022). Patients carrying the C allele of TERC rs2293607 had longer overall survival rates. Extended progression-free survival rates were associated with the presence of the A/A genotype of ACD rs6979. In contrast, in the control cohort, the T/T genotype of CLPTM1L rs401681 was associated with a shorter median progression-free survival.
Disclosure: The study authors’ full disclosures can be found at coi.asco.org.