Characteristics of colorectal cancer in elderly patients.

The aim of the study was to examine the characteristics of colorectal cancer in elderly patients. The medical histories of 178 consecutive patients (79 men and 99 women) with colorectal cancer were studied from hospital records. The studied parameters were compared between three age groups: under 65 years old, 65-80 years old and over 80 years old. In the two older age groups, cancer was situated more commonly in the proximal colon than in the youngest age group (p = 0.029). Especially in elderly subjects, rectosigmoidoscopy is not sufficient since up to 40% of cancers are located in the right colon. Colonoscopy is recommended as the method of choice in old patients if colorectal cancer is suspected. Cancers in the oldest age group more often fell into to Dukes' stages C1, C2 and D (metastatic growth) (p = 0.072) and they were greater in size than those of patients under 80 years old (p = 0.029). Small cancers (under 5 cm) had obvious blood in the stools as the main symptom and represented nonmetastatic Dukes' stages. If these cancers could be detected earlier by testing for occult blood, the prognosis of colorectal cancer would improve. The resectability of cancer was lower in patients over 80 years than in other age groups (p = 0.016). However, in logistic regression analysis, the large size, poor or moderate cell differentiation, and distal location of the cancer, but not age, were associated with poor resectability.