To determine the optimal strategy for prostate cancer screening, the cost-effectiveness of screening was analyzed using a medical decision model. One hundred thousand asymptomatic males between the ages of 40 and 69 were modeled with and without screening. The subjects were divided into three 10−year age groups. We used a 5−year survival rate as an effectiveness point and assumed after 5 year survival free from prostate cancer. We considered three potential programs: 1)screening with digital rectal examination(DRE), 2)screening with prostate specific antigen(PSA), and 3)screening with a combination of DRE and PSA. The study was analyzed from the payer’s perspective, and only direct medical costs were included. For each of the three age groups, PSA screening was more cost−effective than either DRE screening or a combination of DRE and PSA screening. The cost−effectiveness ratio for the combination of DRE and PSA screening was 1.1−2.3 times more expensive than that of PSA screening. If the compliance rate for work−up exams is 80%, the cost−effectiveness of prostate cancer screening is approximate to that of gastric cancer screening. In conclusion, PSA screening is the most cost−effective strategy for prostate cancer screening when compared with both DRE and the combination of DRE and PSA screening. But prostate cancer screening should be carefully conducted, taking the cost−effectiveness of the different strategies and target groups into consideration.
Aspects of disease screening ; public service announcement ; screening for prostate cancer ; Cost aspects ; seconds

A chemical-ecology approach has been used to screen plants growing in Guyana Highlands as an indicator of production of biologically active secondary metabolites. Extracts of leaves from 19 species, most of them endemic in this area, and collected at the top of Roraima Tepui (2,723 m) were screened in vitro at different concentrations for their potential cytotoxic activity against three tumour cell lines: HT29 (colon), A549 (lung) and MDA-MB-231 (breast). MTT (tetrazolium blue) colorimetric assay was employed as cytotoxicity test. Extracts of nine species caused less than 30% growth in at least one cell line. From these species, high cytotoxic activity was detected in Casearia sylvestris var. lingua and Ledotamnus sessiliflorus extracts; medium activity was found in Cyathea sp. Two other species, Cyrilla racemiflora and Heliamphora minor showed lower but significant cytotoxicity. Further cytotoxicity-directed fractionation of these extracts would be advisable to isolate and identify the active principles of these plants.
Cytotoxicity ; Aspects of disease screening ; Cell Line ; MB-2 ; Employed

Participants in our screening program for cerebrovascular disease are supposed to receive thyroid checkups at the time of ultrasound imaging of carotid arteries. Thus far, a total of 4,338 people have participated in this program. Of the total, 17 cases of papillary thyroid carcinoma were found (detection ratio: 0.39%). This study concerned with the 13 cases which underwent surgical treatment in our hospital. They all were diagnosed as early cancers--eight cases at stage N0 and five cases at stage N1--with an average tumor diameter of 11 mm. Besides, five cases of Basedow's disease (hyperthyroidism) and 15 cases of chronic thyroiditis were found (detection ratio: 0.35%). Of the 15 chronic thyroiditis cases, nine were found to have symptoms of hypothyroidism. We concluded that our screening program for cerebrovascular disease involving the ultrasonographic scans of the thyroid gland is very helpful not only in detecting malignancies at an early stage but also in screening for functional abnormalities of the thyroid.
Aspects of disease screening ; Ultrasonography ; Desiccated thyroid ; Thyroid Gland ; Diagnostic Neoplasm Staging

As a health care measure for the people in the prime of life, the Ministry of Health and Welfare (now the Ministry of Health, Labor and Welfare) of the Japanese government started off the first 5-year program for the senior citizens in 1983 with the enforcement of the Law Concerning Health and Medical Services for the Aged, followed by the second five-year program in 1988 and the third eight-year program in 1992. The screening project for colon cancer was incorporated in the third program with a target set of holding an increasing rate of morbidity at zero in a year-to-year comparison. The response rate to colon cancer screening (the ratio of the number of participants responding to colon cancer screening to the total number of qualified persons) was also to be raised steadily to reach a target of 30% in 1999. In Gifu Prefecture, the total number of examinees in 1999 increased twice the figure in 1992, but the response rate was 14.8%, which was only about half the target and below the national average of 15.3%. The detection ratio of colon cancer and the early cancer ratio in the prefecture were much the same as the national average. It could be taken that there is nothing wrong as far as the precision of screeming and management are concernd. To decrease the rate of mortality from cancer of the colon, the most important is to raise the response rate. For this purpose, we would like to propose that the cost should be covered by national health insurance in those health screening projects approved of by the competent authorities.
Malignant tumor of colon ; Aspects of disease screening ; Health ; Cancer treatment response rate ; Federal Government

Local residents were screened for colorectal cancer, and the results during six year period are reported. The two-day immunological fecal occult blood test was used as the first screening method. The barium enema radiography was used as the secondary screening method even if only one of the occult blood reactions was positive. Images were acquired in varius directions from rectum to the sigmoid colon (the most common site of colorectal cancer) and at least anterior-posterior images in two directions were obtained another sites as well. Barium enema radiography is less distressing to patients than the endoscopy of entire large intestine and can be carried out quickly. In addition, its accuracy is considered comparable to that of endoscopy, and the results of our study were no poorer than that obtained in institutions where only endoscopy was carried out.
Diagnostic radiologic examination ; Endoscopy ; Enema Solution ; Aspects of disease screening ; Barium enema, NOS