Quels fixateurs ? Pour quelles indications ? Principaux critères d'évaluation des méthodes alternatives à la fixation par le formol

Since formalin has been recognized as carcinogen agent and since the modification of the French legislative and law, the French pathologist practice has suddenly change because of the necessity to apply new protective and safety procedures in pathology laboratories. French pathologists have then the choice to remove the formalin from their routine practice, and to use substitute fixatives, which contained no or a few amount of aldehydes. This substitution can allow to reduce the toxic risks in a pathology laboratory and in all health Institutions. Moreover, this practice may increase and improve the results of certain molecular biology methods made from fixed tissues. Then, the replacment of formalin has two goals, 1) to reduce the exposure of laboratory workers to this potential carcinogene, 2) to lead molecular biology and proteomic technics development because of a better preservation of the nucleic acides and protein structures. However, the use of substitute fixatives must be done after the control of different steps and criteria which will be describe here. Moreover this replacement is currently not performed in all European countries and may limit French teams involvement in certain multicentric collaborative studies.