Clinical Trial Service Unit

About: Clinical Trial Service Unit is a based out in . It is known for research contribution in the topics: Population & Stroke. The organization has 428 authors who have published 1387 publications receiving 181920 citations.

Cardiac Dose From Tangential Breast Cancer Radiotherapy in the Year 2006

Abstract: Purpose To quantify the radiation doses received by the heart and coronary arteries from contemporary tangential breast or chest wall radiotherapy. Methods and Materials Fifty consecutive patients with left-sided breast cancer and 5 consecutive patients with right-sided breast cancer treated at a large United Kingdom radiotherapy center during the year 2006 were selected. All patients were irradiated with 6- or 8-MV tangential beams to the breast or chest wall. For each dose plan, dose–volume histograms for the heart and left anterior descending (LAD) coronary artery were calculated. For 5 of the left-sided and all 5 right-sided patients, dose–volume histograms for the right and circumflex coronary arteries were also calculated. Detailed spatial assessment of dose to the LAD coronary artery was performed for 3 left-sided patients. Results For the 50 patients given left-sided irradiation, the average mean (SD) dose was 2.3 (0.7) Gy to the heart and 7.6 (4.5) Gy to the LAD coronary artery, with the distal LAD receiving the highest doses. The right and circumflex coronary arteries received approximately 2 Gy mean dose. Part of the heart received >20 Gy in 22 left-sided patients (44%). For the 5 patients given right-sided irradiation, average mean doses to all cardiac structures were in the range 1.2 to 2 Gy. Conclusions Heart dose from left-tangential radiotherapy has decreased considerably over the past 40 years, but part of the heart still receives >20 Gy for approximately half of left-sided patients. Cardiac dose for right-sided patients was generally from scattered irradiation alone.

Uncovering the effects of smoking: historical perspective.

Abstract: Tobacco was introduced into Europe from America at the end of the fifteenth century. At first used primarily for medicinal purposes it came to be burnt in pipes for pleasure on a large scale nearly 100 years later, at first in England and subsequently in Europe and throughout the world. Pipe smoking gave way to the use of tobacco as snuff and, in turn, to cigars and cigarettes at different times in different countries until cigarette smoking became the dominant form in most of the developed world between the two world wars. Societies were formed to discourage smoking at the beginning of the century in several countries, but they had little success except in Germany where they were officially supported by the government after the Nazis seized power.In retrospect it can now be seen that medical evidence of the harm done by smoking has been accumulating for 200 years, at first in relation to cancers of the lip and mouth, and then in relation to vascular disease and cancer of the lung. The evidence was genera...