Screening for lung cancer: U.S. Preventive Services Task Force recommendation statement.

DESCRIPTION: Update of the 2004 U.S. Preventive Services Task Force (USPSTF) recommendation on screening for lung cancer. METHODS: The USPSTF reviewed the evidence on the efficacy of low-dose computed tomography, chest radiography, and sputum cytologic evaluation for lung cancer screening in asymptomatic persons who are at average or high risk for lung cancer (current or former smokers) and the benefits and harms of these screening tests and of surgical resection of early-stage non-small cell lung cancer. The USPSTF also commissioned modeling studies to provide information about the optimum age at which to begin and end screening, the optimum screening interval, and the relative benefits and harms of different screening strategies. POPULATION: This recommendation applies to asymptomatic adults aged 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years. RECOMMENDATION: The USPSTF recommends annual screening for lung cancer with low-dose computed tomography in adults aged 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery. (B recommendation).

UTILITY OF ROUTINE CHEST RADIOGRAPHS IN KENYA.

BACKGROUND: Many otherwise healthy Kenyans are required to obtain chest radiographs as part of routine medical examination to exclude pulmonary TB, a condition of significant public health concern. Many of these people are required to have these radiographs taken yearly as part of routine check-up. No local data is available to support this practice. Though a quick procedure to perform and readily available throughout the country, chest radiograph exposes the individual to a dose of ionising radiation. Ionising radiation is associated with increased risk of malignancy. The cost is also substantial. OBJECTIVE: To determine the prevalence of radiological findings consistent with PTB among routine medical examination chest radiographs. DESIGN: A cross-sectional descriptive study. SETTINGS: Department of Radiology Kenyatta National Hospital, Department of Imaging and Radiation Medicine, University of Nairobi, Plaza Imaging Solutions, a private radiology practice in Nairobi and Department of Radiology, the Nairobi Hospital. SUBJECTS: Four hundred and two chest radiographs of patients presenting for routine medical examinations were analysed. RESULTS: Sixty three radiographs had abnormal but clinically insignificant findings (16%). Only one radiograph (0.25%) had radiological features of PTB. The rest were reported as normal (84%). CONCLUSION: In this study, the diagnostic yield for the intended purpose (to include/ exclude PTB) was extremely low (0.25%). It is recommended that routine chest radiographs as screening tools for active pulmonary tuberculosis be reconsidered due to poor diagnostic yield. The authors propose a bigger nation wide study before a policy decision can be proposed.

The futility of universal pre-employment chest radiographs.

In a developmental center, a preemployment chest x-ray was required for all job applicants. We scrutinized the pros and cons of this practice through a review of the medical literature and our experience, and discussion with our colleagues. We concluded that such chest x-ray caused unwarranted radiation exposure, did not produce compliance with the tuberculosis laws, gave a false sense of security regarding workers' compensation risk management, was contrary to established occupational medicine practice guidelines, and was unnecessary and wasteful. We discontinued such chest x-rays. The purpose of the pre-employment examination should remain narrowly job related. Even long-established procedures require periodic utilization review.

[Initial cost-benefit analysis of chest fluoroscopy in synthetic clue investigation on tuberculosis].

Body surface exposure to X-ray radiation was measured in those with synthetic clue investigation on tuberculosis. The results showed body surface exposure in them appeared a logarithmic normal distribution with a geometric mean of 0.19 mC/kg and was higher than that with fluoroscopy in routine check-ups. The late effect of X-ray radiation showed 0.52 hours of an average life-span cut. But, based on prevalence, mortality and cure rate of chemotherapy for tuberculosis in Jiangsu Province, chest fluoroscopy in synthetic clue investigations brought an average prolongation of 45.8 hours per person in life-span of those X-rayed. Comparison of life-span showed synthetic clue investigation was an adequate method in active tuberculosis case-finding from the viewpoint of radiation protection.