Although they are more likely to be diagnosed with stage III or IV colorectal cancer, patients under the age of 40, as well as those under 50, have similar survival time and response to treatment as older people.
Young people had about twice the severe nausea and vomiting as older patients, but were less likely to have lowered white cell counts. They had similar rates of serious diarrhea.
Colorectal cancer is primarily a disease of aging, with only 1 in 20 patients diagnosed under the age of 50. The average age for diagnosis now is 72 years and nearly a third of cancers are found after age 80.
Contrary to belief, young patients also participate in clinical trials. Although only 4.6 percent of advanced colorectal cancer patients are under 50, 13 percent of patients in the nine trials studied were younger than 50.
A research team led by Charles D. Blanke of the University of British Columbia reviewed the combined statistics of nine randomized clinical trials for the initial (first-line) treatment of advanced colorectal cancer. They looked at response rates, progression-free survival, overall survival, and rates of serious (grade 3 and 4) treatment side effects for 6,282 patients, including 793 (13%) who were under 50 and 188 (3%) who were less than 40 years old.
The trials were conducted from 1995 through 2004 and had arms that included 5-FU as a single drug and in combination with oxaliplatin and irinotecan.
When patients under 40 were compared with those 40 and older:
- Tumor response rates were equivalent (41% vs 43%)
- Median progression-free survival was not statistically different (5.9 months vs. 7.4 months)
- Median overall survival time was almost the same (16.2 months vs 16.5 months)
- Younger patients had more nausea (14% vs. 7%), more vomiting (15% vs. 6%), but similar rates of diarrhea and mouth sores.
When patients under 50 were compared with those 50 and older.
- Response rates were equivalent (42% vs. 43%)
- Progression-free survival was slightly worse (6.0 months vs 7.5 months) but this didn’t impact overall survival time.
- Overall survival time was equivalent (15.8 vs.16.6)
- They had more nausea (10% vs. 7%), vomiting (9% vs. 6%), but less diarrhea (11% vs. 14%), and less neutropenia (23% vs. 26%).
Dr. Blanke and his colleagues concluded,
Young age is modestly associated with poorer progression free survival (PFS) but not overall survival (OS) or response rate (RR) in treated patients with advanced colorectal cancer, and young patients have more nausea but less diarrhea and neutropenia with chemotherapy ingeneral. Young versus older patients derive the same benefits from combination chemotherapy. Absent results of a clinical trial, standard combination chemotherapy approaches are appropriate for young patients with advanced CRC.