Comparison of comprehensive genomic profiles between young-onset and average-onset colorectal cancer.

Abstract

167 Retraction The abstract by Torrejon et al entitled, “Comparison of comprehensive genomic profiles between young-onset and average-onset colorectal cancer.,” ( Journal of Clinical Oncology 40, no. 4, suppl 167) published on January 19, 2022, has been retracted due to calculation errors. Current age was used for the analysis instead of age at diagnosis. This error significantly changed the results and conclusion of the abstract. Background: The incidence of young-onset colorectal cancer (yoCRC) is rising for unknown reasons. This study assessed for differences in comprehensive genomic profiles between yoCRC and average-onset colorectal cancer (aoCRC). Methods: All patients with CRC seen at Cleveland Clinic that had tumor-based next generation sequencing (NGS) performed as part of their care with a clinically available assay between January 2017 and September 2020 were included. The cohort was divided based on age of diagnosis, with yoCRC defined as age of CRC diagnosis <50 years old. All clinical data and genomic alterations were included for analysis. We assessed for differences in clinical data and NGS findings between yoCRC and aoCRC using Fisher’s exact test, adjusted for primary tumor sidedness. Overall survival (OS) by genomic alteration was estimated by Kaplan-Meier methods and compared using log rank test. Results: The study population comprised of 51 yoCRC patients and 211 aoCRC patients. There were no significant differences in sex, race or ethnicity between yoCRC and aoCRC patients. Compared to aoCRC patients, yoCRC patients were more likely to present at diagnosis with stage IV disease (81% vs. 56%, p = 0.02) and have left-sided primary tumors (69% vs. 60%, p = 0.26). YoCRC tumors were more likely to have mutations in APC, KRAS, TP53 and FLT3 compared to aoCRC tumors, independent of tumor sidedness. These data are summarized in Table. Compared to left-sided tumors, right-sided tumors had significantly higher frequency of KRAS (67.7% vs. 48.8%, p = 0.003), BRAF (15.2% vs. 3.1%, p = 0.0006) and PTEN (16.2% vs. 3.1%, p value = 0.0003) alterations. AoCRC patients had significantly longer OS compared to yoCRC patients (median OS: 70.0 months vs. 36.3 months, p=0.004). Black (37.2 months, n=35) and Asian (37.8 months, n=7) patients had significantly worse median OS compared to White patients (67.8 months, n=199), p-value 0.005. In the overall population, patients with APC mutations had significantly better OS compared to those with APC wildtype tumors (median OS: 92.6 months vs. 54.4 months, p=0.001). Patients with FLT3 mutations had worse median OS compared to those with FLT3 wildtype tumors (median OS: 42.0 months vs. 64.8 months, p=0.007). There were no survival differences based on MSI status. Conclusions: In this series, yoCRC patients were more likely to present with stage IV disease and experienced worse OS compared to aoCRC patients. YoCRC patients were more likely to have mutations in APC, KRAS, TP53 and FLT3, independent of tumor sidedness. Mutations in FLT3 correlated with worse OS.[Table: see text]