Description: Background: Breast-cancer incidence and mortality have been increasing in Japan. Japanese-specific clinical validity and utility data for the 21-gene assay (Oncotype DX(R) Breast Cancer Assay; Genomic Health, Inc., Redwood City, USA) are now available. The objective of this study was to evaluate the cost-effectiveness of the 21-gene assay for the guidance of adjuvant chemotherapy decisions in estrogen-receptor-positive, lymph-node-negative, early-stage breast cancer patients, from the Japanese societal perspective. Methods: The recurrence risk group distribution by the 21-gene assay result and the assay's influence on adjuvant chemotherapy recommendations were obtained from a study of 104 patients. A state-transition cohort (Markov) model tracked time from surgery until distant recurrence and from distant recurrence to death. Adjuvant chemotherapy benefit by 21-gene assay risk group was based on published clinical validation studies. Direct and indirect medical costs were obtained from the referral centers. Utilities associated with progression and chemotherapy-related adverse events were extracted from literature. Sensitivity analyses assessed the key drivers and robustness of the primary outcomes. Results: The 21-gene assay identified 48% of patients as low-risk, 36% as intermediate-risk, and 16% as high-risk. Total acute chemotherapy-related costs decreased by [yen sign]154,066 due to less adjuvant chemotherapy usage. In the high-risk group, adjuvant chemotherapy use increased 18%, leading to survival benefits. Chemotherapy use overall decreased by 19%. Monitoring costs increased by [yen sign]3,744 but recurrence costs declined by [yen sign]46,113 per patient. Use of the 21-gene assay increased quality-adjusted-life-years (QALYs) by 0.241 per patient on average; the net cost per QALY gained was [yen sign]636,752 ($6,368). Conclusions: The 21-gene assay for women with estrogen-receptor-positive, lymph-node-negative, early-stage breast cancer is projected to be cost-effective in Japan.

Description: Background: Several genetic polymorphisms have been reported to modify the effects of smoking on serum lipid levels. The objective of this study was to investigate whether longevity-associated mitochondrial DNA 5178 (Mt5178) C/A polymorphism modifies the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese subjects. Methods: A total of 394 male subjects (age, 53.9 +/- 7.9 years; mean +/- SD) were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the joint effect of Mt5178 C/A polymorphism and cigarette smoking on the risk of hypo-high-density lipoprotein (HDL) cholesterolemia, hyper-low-density lipoprotein (LDL) cholesterolemia or hypertriglyceridemia was conducted. Results: For subjects with Mt5178C, the risk of hypo-HDL cholesterolemia increased with the number of cigarettes smoked daily (P for trend = 0.001). On the other hand, the association between Mt5178A genotype and the risk of hypo-HDL cholesterolemia did not appear to depend on the number of cigarettes smoked daily. For those with Mt5178A, the risk of hyper-LDL cholesterolemia or hypertriglyceridemia increased with cigarettes smoked daily (P for trend = 0.017 and P for trend = 0.002, respectively). However, the association between Mt5178C genotype and the risk of hyper-LDL cholesterolemia or hypertriglyceridemia did not depend on the number of cigarettes smoked daily. Conclusions: The present results suggest that Mt5178 C/A polymorphism modulates the effects of habitual smoking on the risk of dyslipidemia in middle-aged Japanese men.

Description: Background: Prevention of chronic kidney disease (CKD) is a major public health issue. Although several studies have been performed on the association between alcohol consumption and CKD or renal function, it remains controversial. Numerous genetic polymorphisms have been reported to be associated with CKD and kidney function. Mitochondrial DNA cytosine/adenine (Mt5178 C/A) polymorphism is associated with longevity in Japanese. This polymorphism modifies the effects of alcohol consumption on blood pressure, risk of hypertension, serum triglyceride levels, risk of hyper-LDL cholesterolemia and serum uric acid levels. The objective of this study was to investigate whether Mt5178 C/A polymorphism modifies the effects of alcohol consumption on renal function in male Japanese health check-up examinees. Methods: A total of 394 male subjects aged 29--76 years were selected from among individuals visiting the hospital for regular medical check-ups. After Mt5178 C/A genotyping, a cross-sectional study assessing the combined effects of Mt5178 C/A polymorphism and habitual drinking on the risk of mildly decreased estimated glomerular filtration rate (eGFR) (