No increase in colorectal cancer in patients under 50 years of age: a Victorian experience from the last decade.

AIM

The study aimed to assess whether there has been an increase in the incidence of colorectal cancer (CRC) among young patients in Victoria and whether such cancers are more advanced at presentation.

METHOD

The Victorian Cancer registry database was searched for patients, 18-50 years of age, diagnosed with CRC [young colorectal cancer (YCRC)] between 2000 and 2010. Average annual percentage changes and incidence rate ratios (IRRs) were calculated to characterize trends in CRC rates over time and to make comparisons with patients over 50 years of age with CRC [late colorectal cancer (LCRC)].

RESULTS

Of 37432 CRCs registered during the study period, 2635 (7%) were in YCRC patients (annual increase in incidence = 1.7%; 95% CI: 0.5-2.9), compared with 34797 (93%) in LCRC patients (annual increase in incidence = 1.3%; 95% CI: 0.9-1.6). A small, nonsignificant increase in the incidence of YCRC over time was observed [IRR = 1.004 (95% CI: 0.992-1.016) for YCRC vs. 0.989 (95% CI: 0.986-0.992) for LCRC]. Rectal cancer was more common in YCRC patients than in LCRC patients (42% vs. 34%, respectively; P < 0.0001). The cancer would have been seen on flexible sigmoidoscopy in 63% of YCRC patients compared with 53.6% of LCRC patients (P < 0.0001). YCRC patients were more likely to have node-positive disease (49.3% YCRC patients vs. 40% LCRC patients; P < 0.0001), especially those with colonic cancer (52.7% YCRC patients vs. 41.2% LCRC patients; P < 0.0001).

CONCLUSION

There has been an increase in incident cases of YCRC. A small, nonsignificant increase in the incidence of YCRC over time was observed. Young patients are more likely to have rectal cancer and to be node positive.