Another study has found better survival after a diagnosis of colorectal cancer in younger women. Among over two thousand colon and rectal cancer patients In Australia, women under the age of 50 had about half the risk of dying from colorectal cancer than men under 50. Better survival held true despite where the cancer was found, its stage or grade, and whether emergency surgery was necessary to treat it.
However, women over 50 had about 40 percent poorer survival than men over 50. Again, stage, site, or grade at the time of diagnosis didn’t matter.
The South Western Sydney Colorectal Tumour Group registry studied data for men and women diagnosed with colorectal cancer between 1997 and 2004. Compared to men, women
- were older at diagnosis (median age 69 versus 67 for men)
- were more likely to have tumors on the right side of their colons (42.2% of women vs. 31.5% of men)
- needed emergency surgery more often (18.8% vs. 15.1%)
- had more poorly differentiated tumors (16.9% vs. 12.9%)
Women were less likely to receive radiotherapy treatment for rectal cancer. A little over a third of women with rectal cancer (36.4 percent) had radiation treatment compared to almost half of men (48.1 percent). However, there were no differences in treatment with chemotherapy.
There were also no differences in stage at diagnosis or tumor pathology.
The study did not include information about use of estrogen therapy or actual data on whether women had experienced menopause.
Dr. Jenn H. Koo and her colleagues in Sydney concluded,
This study demonstrated an opposing effect of gender on overall and cancer-specific survival at either side of the age of 50 years. The protective effect of estrogen on CRC may be an important factor. Women had a greater proportion of emergency surgery, which was related to the predominance of proximal cancers in this gender. Women also had more proximal cancers, thereby limiting flexible sigmoidoscopy as a screening test.
Another article about the study is available from Reuters Health.
SOURCE: Koo et al., American Journal of Gastroenterology, Volume 103, Issue 6, June 2008.