PSA高値患者への低脂肪高大豆蛋白食のDietary interventionの試み - 食事指導後のQOLの変化及び短期的なPSAの変化 -

Abstract

前立腺特異抗原(PSA)高値のため前立腺癌の疑いで受診した182名を対象に, 食事指導後の患者の意欲, QOLに関するアンケート調査を施行した.プロトコールにより61例の前立腺癌が発見され, 残り121名中performance statusが良く, 指導の概要を説明し, 承諾が得られた96例(51～80歳)に対し栄養指導を行った.96例中3例は脱落, 2例は高度排尿障害でTUR-Pを受けた.経過観察中3例に前立腺癌が発見された.これらを除いた60名(68%)よりアンケートを回収した.指導3ヵ月後, 患者のほとんどが指導を守っており, 食生活に関するQOLの低下は全体の20%弱であった.一方, PSAはP平均6.9ng/mlから5.6ng/mlに有意に低下した

Considerable epidemiological evidence has indicated a relationship between diet and prostate cancer. Many studies have shown positive associations between dietary fat and prostate cancer, and inverse associations with soybean intake. To prevent prostate cancer, we have tried dietary intervention for patients showing an elevated prostate specific antigen (PSA) level. A total of 96 patients who did not show any evidence of prostate cancer by transrectal ultrasonography and/or prostate biopsy despite high serum PSA level were placed on a supervised dietary intervention program consisting of a low fat and high soybean protein diet. The primary endpoint was the alteration of quality of life (QOL) and PSA after 3 months of intervention. Response to the questionnaire indicated that 88% of the patients desired to join such a study, and that 90% of the patients continued the dietary control after 3 months of supervision. About 60% patients adhered strictly to the dietary menus, and 90% of the subject planed to continue. Less than 20% of the patients complained of deterioration of dietary QOL. The average serum PSA level decreased from 6.9 ng/ml to 5.6 ng/ml after 3 months, which was statistically significant (p = 0.01). This dietary intervention almost maintains the patient's QOL, decreases the serum PSA level, and indicates the possibility of prevention of prostate cancer by dietary intervention.