Researchers affiliated with a RAND Corporation study have reported that older patients in the community with Stage III colorectal cancer “received less-toxic and shorter chemotherapy regimes, and those treated had fewer adverse events than younger patients.” The details of this study were published in the March 17, 2010 issue of the Journal of the American Medical Association.[1]

Randomized trials have clearly demonstrated that adjuvant chemotherapy improves survival in patients with Stage III colon cancer by approximately 30%. In 1990 a National Institutes of Health Consensus Conference recommended that patients with Stage III colon cancer receive an adjuvant 5-FU based regimen. There is also recent data to suggest benefit in Stage II patients. Several previous studies have shown that elderly patients benefit from adjuvant chemotherapy to the same degree as younger patients but are less likely to actually receive this therapy. Researchers from France have previously reported that patients 75 years of age or older with Stage III colon or rectal cancer receiving adjuvant chemotherapy or radiotherapy did not have negative effects on quality-of-life parameters compared with patients not receiving adjuvant therapy.

The current study evaluated data on 675 patients with Stage III colon cancer from five U.S. geographical regions. Two hundred and two of these patients were 75 years of age or older.

• 50% of patients 75 years of age or older received adjuvant chemotherapy compared with 97% of younger patients.
• 14% of older patients received oxaliplatin in the adjuvant regimen compared with 44% of younger patients.
• Older patients received a shorter course of adjuvant chemotherapy than younger patients.
• Patients receiving adjuvant chemotherapy had more adverse events than non-treated patients.
• Late adverse events were lower in older patients than in younger patients, which may have been due to less intensive adjuvant therapy.

Comments: This study shows that only half of older patients in the community receive adjuvant chemotherapy for Stage III colon cancer despite the proven benefits. The impact of dose-reduction of adjuvant chemotherapy in this age group is unknown and needs to be studied.