[French radiotherapy database: results of a survey of French radiation oncology centers in 2007].

For the second year, the French Radiotherapy Database presents information from French radiation oncology centers. Among 179 centers, 159 have participated (90 %). The number of accelerators increased from 371 to 384 between 2006 and 2007, 11 % of these machines are more than 15 years old.

[Guide for external beam radiotherapy. Procedures 2007].

In order to optimize quality and security in the delivery of radiation treatment, the French SFRO (Société française de radiothérapie oncologique) is publishing a Guide for Radiotherapy. This guide is realized according to the HAS (Haute Autorité de santé) methodology of "structured experts consensus". This document is made of two parts: a general description of external beam radiation therapy and chapters describing the technical procedures of the main tumors to be irradiated (24).

[Image quality and optical density in mammography: study on phantoms].

Optical densisty (od) is an important factor for image quality in mammography. We studied the effect of o.d.