TOPLINE:
In patients with stages I-III colorectal cancer (CRC) who are cancer-free 5 years after surgery, the incidence of late recurrence or metachronous disease after 5 years is low and has decreased over time, new data showed.
METHODOLOGY:
- Recent treatment advances in CRC have reduced the likelihood that patients with nonmetastatic disease will recur or develop a second primary cancer more than 6 months after the first. Although late recurrences and metachronous CRC remain infrequent, it’s not clear if patients might benefit from longer term surveillance.
- To investigate whether extending surveillance beyond the recommended 5 years is beneficial, researchers assessed the incidence of late recurrence, metachronous CRC, and second primary cancers 5 years after surgical resection with curative intent.
- The researchers identified patients with stages I-III CRC, under age 80 years, from Danish healthcare registries who underwent surgical resection between January 2004 and December 2013.
- A total of 8883 patients were followed from 5 years after primary surgery until the date of recurrence, metachronous CRC, or second non-CRC primary cancer.
TAKEAWAY:
- Between 5 and 10 years after surgery, 370 survivors developed late recurrence (4.16%), 270 developed metachronous disease (3.0%), and 635 were diagnosed with a second primary cancer (7.15%).
- During 2009-2013 and 2004-2008, the risk for late recurrence decreased by 48% (5.6% vs 2.9%; subdistribution hazard ratio [sHR], 0.52) and the risk for metachronous disease decreased by 50% (4.1% vs 2.1%; sHR, 0.50).
- During the same timeframe, the risk for second non-CRC primary cancer remained unchanged (7.1% vs 7.1%; sHR, 0.98).
- Compared with patients diagnosed with late recurrences (46%), 5-year overall survival was higher for patients with metachronous CRC (72%; adjusted HR, 0.37) and slightly higher for those with second primary cancers (48%; adjusted HR, 0.78).
IN PRACTICE:
Because the incidences of late recurrence and metachronous CRC are low and decreased between 2004 and 2013, the data do not support extending CRC-specific surveillance beyond 5 years, the authors concluded. “Symptoms or suspicion of a cancer occurring 5-10 years from primary CRC treatment, is more likely to represent a non-CRC cancer (7.1%).”
SOURCE:
This study, led by Jesper Nors from Aarhus University Hospital, Aarhus, Denmark, was published on February 7, 2024, in the International Journal of Cancer.
LIMITATIONS:
Misclassification of a late recurrence or metachronous CRC could have affected the findings.
DISCLOSURES:
This work was funded by Institute of Clinical Medicine, Aarhus University, Denmark, Novo Nordisk Foundation, Innovation Fund Denmark, and the Danish Cancer Society. The authors reported no conflict of interests.
A version of this article appeared on Medscape.com.