Metachronous Advanced Neoplasia on Surveillance Colonoscopy in Patients With Young- vs Older-onset of Colorectal Cancer

Risk of metachronous neoplasia in early-onset colorectal cancer: meta-analysis

BACKGROUND

Metachronous colorectal cancer refers to patients developing a second colorectal neoplasia diagnosed at least 6 months after the initial cancer diagnosis, excluding recurrence. The aim of this systematic review is to assess the incidence of metachronous colorectal cancer in early-onset colorectal cancer (defined as age at diagnosis of less than 50 years) and to identify risk factors.

METHODS

This is a systematic review and meta-analysis performed following the PRISMA statement and registered on PROSPERO. The literature search was conducted in PubMed and Embase. Only studies involving patients with early-onset colorectal cancer (less than 50 years old) providing data on metachronous colorectal cancer were included in the analysis. The primary endpoint was the risk of metachronous colorectal cancer in patients with early-onset colorectal cancer. Secondary endpoints were association with Lynch syndrome, family history and microsatellite instability.

RESULTS

Sixteen studies met the inclusion criteria. The incidence of metachronous colorectal cancer was 2.6% (95% c.i. 2.287-3.007). The risk of developing metachronous colorectal cancer in early-onset colorectal cancer versus non-early-onset colorectal cancer patients demonstrated an OR of 0.93 (95% c.i. 0.760-1.141). The incidence of metachronous colorectal cancer in patients with Lynch syndrome was 18.43% (95% c.i. 15.396-21.780), and in patients with family history 10.52% (95% c.i. 5.555-17.659). The proportion of metachronous colorectal cancer tumours in the microsatellite instability population was 19.7% (95% c.i. 13.583-27.2422).

CONCLUSION

The risk of metachronous colorectal cancer in patients with early-onset colorectal cancer is comparable to those with advanced age, but it is higher in patients with Lynch syndrome, family history and microsatellite instability. This meta-analysis demonstrates the need to personalize the management of patients with early-onset colorectal cancer according to their risk factors.

Early-onset Colorectal Cancer Patients Do Not Require Shorter Intervals for Post-surgical Surveillance Colonoscopy

BACKGROUND & AIMS

Early-onset colorectal cancer (EO-CRC), diagnosed before age 50, is rising in incidence worldwide. Although post-surgical colonoscopy surveillance strategies exist, appropriate intervals in EO-CRC remain elusive, as long-term surveillance outcomes remain scant. We sought to compare findings of surveillance colonoscopies of EO-CRC with patients with average onset colorectal cancer (AO-CRC) to help define surveillance outcomes in these groups.

METHODS

Single-institution retrospective chart review identified EO-CRC and AO-CRC patients with colonoscopy and no evidence of disease. Surveillance intervals and time to development of advanced neoplasia (CRC and advanced polyps [adenoma/sessile serrated]) were examined. For each group, 3 serial surveillance colonoscopies were evaluated. Statistical analyses were performed utilizing log-ranked Kaplan-Meier method and Cox proportional hazards.

RESULTS

A total of 1259 patients with CRC were identified, with 612 and 647 patients in the EO-CRC and AO-CRC groups, respectively. Compared with patients with AO-CRC, patients with EO-CRC had a 29% decreased risk of developing advanced neoplasia from time of initial surgery to first surveillance colonoscopy (hazard ratio, 0.71; 95% confidence interval, 0.52-1.0). Average follow-up time from surgical resection to first surveillance colonoscopy was 12.6 months for both cohorts. Overall surveillance findings differed between cohorts (P = .003), and patients with EO-CRC were found to have less advanced neoplasia compared with their counterparts with AO-CRC (12.4% vs 16.0%, respectively). Subsequent colonoscopies found that, while patients with EO-CRC returned for follow-up surveillance colonoscopy earlier than patients with AO-CRC, the EO-CRC cohort did not have more advanced neoplasia nor non-advanced adenomas.

CONCLUSIONS

Patients with EO-CRC do not have an increased risk of advanced neoplasia compared with patients with AO-CRC and therefore do not require more frequent colonoscopy surveillance than current guidelines recommend.

Young adults and metachronous neoplasia: risks for future advanced adenomas and large serrated polyps compared with older adults

BACKGROUND AND AIMS

Recent increases in colorectal cancer (CRC) incidence in adults younger than 50 years of age have led to more colonoscopies in this age group. As a result, there may be an increasing number of adults <50 years old with polyps detected. There is concern that younger adults may require closer follow-up. Our goal was to use data from the New Hampshire Colonoscopy Registry (NHCR) to examine the risk for metachronous advanced adenomas (AAs) and large (>1 cm) serrated polyps in younger versus older adults who return for a follow-up colonoscopy.

METHODS

Our cohort consisted of NHCR participants with at least 1 polyp on index examination and a follow-up colonoscopy at least 1 year after the index examination. Outcomes were the risks for metachronous AAs (adenomas ≥1 cm, with villous elements or high-grade dysplasia, or CRC) and large (≥1 cm) serrated polyps. We present absolute risk and adjusted risks from a logistic regression model stratified by age at index colonoscopy (<40, 40-49, 50-59, and 60+ [reference]). Covariates included index findings, endoscopist adenoma detection rates, sex, smoking, body mass index, follow-up time (months), bowel preparation quality, and family history of CRC.

RESULTS

In our sample of 12,380 adults, absolute risk for metachronous AA was lower for younger patients than for patients aged ≥60. After adjusting for covariates, when comparing with the 60+ group (reference), the lowest risk was observed in those younger than 40 years (odds ratio, .19; 95% confidence interval, .05-.80). Of note, similar risks were observed in the 40 to 49 age group (odds ratio, .61; 95% confidence interval, .41-.92) and 50 to 59 age group (odds ratio, .71; 95% confidence interval, .58-.86). The risk for large metachronous serrated polyps was not associated with age.

CONCLUSIONS

Younger adults aged <40 with index adenomas had a lower risk for metachronous AAs than those aged ≥60. The 40- to 49-year age group was found to have metachronous risk similar to the 50- to 59-year age group, with both less than the ≥60 age group. These data suggest that current surveillance interval guidelines for patients aged ≥50 years may appropriately be used with younger adults.