Cancer pancreatic type

This year, it is estimated that 29,700 individuals will be diagnosed with pancreatic cancer in the United States alone. As the five-year survival rate for this type of cancer is extremely low (4%), means of prevention are necessary. With the exception of cigarette smoking, few risk factors for pancreatic cancer have been identified. Recent reviews do however favor a causal association between diabetes mellitus and pancreatic cancer. Additionally, in a number of studies, overweight individuals were consistently at higher risk of pancreatic cancer when compared with leaner individuals. The associations between body weight and diabetes suggest that insulin resistance may play a role in pancreatic carcinogenesis. Due to these recent suggestions, dietary factors that increase postprandial plasma glucose levels may have a direct impact on pancreatic cancer risk. Therefore, investigators examined glycemic index, glycemic load, sucrose, fructose, and carbohydrate intakes in relation to the risk of pancreatic cancer in a large prospective cohort of women with 18 years of follow-up.

The cohort utilized in this investigation was the Nurses' Health Study (NHS). After excluding participants with incomplete dietary questonnaires, very high or low caloric intakes or a cancer diagnosis prior to baseline, 88,802 women were eligible for analysis. A 61-item food-frequency questionnaire (FFQ) was mailed to all participants.

Glycemic index is based on the postprandial blood glucose response compared with the glucose response to a reference food. Using glycemic index values, investigators calculated the average dietary glycemic load (GL) during the past year for each participant by multiplying the carbohydrate content for each food by its glycemic index value, multiplying that product by the frequency of consumption, and summing values for all reported food items. Height, weight, and smoking history were reported and body mass index (BMI) was estimated. Physical activity was also measured. Participants were asked to report specified medical conditions, including cancers that were diagnosed in the two-year period between each follow-up questionnaire. When a subject (or next-of-kin) reported a diagnosis of pancreatic cancer, the study researchers asked for permission to obtain related medical records or pathology reports.

Results indicate that carbohydrate and sucrose intake were not associated with overall pancreatic cancer risk in this cohort. A statistically nonsignificant 53% increase in risk of pancreatic cancer (RR = 1.53, 95% CI = 0.96 to 2.45) was seen among women with a high glycemic load intake, and a similar association was observed for fructose intake (RR = 1.57, 95% CU = 0.95 to 2.57). The associations of glycemic load and fructose intakes with pancreatic cancer risk were most apparent among women with elevated body mass index (> 25 kg/[m.sup.2]) or with low physical activity.

This data support previous findings that impaired glucose metabolism may indeed play a role in the development of pancreatic cancer. It appears that a diet high in glycemic load may increase the risk of pancreatic cancer in women who already have an underlying degree of insulin resistance.

D. Michaud, S. Liu, E. Giovannucci, et al. Dietary sugar, glycemic load, and pancreatic cancer in risk in a prospective study. J Natl Cancer Inst; 94:1293-1300 (September 4, 2002). [Correspondence: Dominique Michaud, Sc.D, National Cancer Institute, 6120 Executive Blvd., EPS Rm. 3032, Rockville, MD 20852. E-mail: michaudd@mail.nih.gov].