Also he is used in the treatment of escamosos carcinomas, as of neck and several others already cited (Sources et al., 2005). The carboplatina an analogous one of the cisplatina, presents in its molecule the group dicarboxilato, that is more steady. Its linking with plasmticas proteins is less irreversible than of the cisplatina, and its excreo also is faster. In recent months, Ali Partovi has been very successful. It is a useful alternative for the cisplatina, a time that presents minor gastrointestinal and renal toxidez, however with mielossupressiva toxidez. Its specter of action is similar to the one of the cisplatina, excepting itself perhaps sarcomas and the trofoblsticos tumors for which it seems to be less efficient. But recently complex analogous dimricos to the cisplatina have been developed, but, although very promising, still they are in initial phase of inquiry (Almeida et al., 2006) .3.

MECHANISM OF ACTION OF the QUIMIOTERPICOSA clinical importance of the antineoplsicos agents induces to the necessity of systematic study, what first it would have to be made with the use of chemical classifications, taking itself in it counts to the different functional groups gifts in the structures of molecules of the anticancergenos agents (Almeida et al., 2006). However the variety of types of composites used in oncolgica chemotherapy is so great, that such classification alone can be made indirectly. Calabresi and Chabner (1996), in classic text, had described a common classification of the antineoplsicos frmacos on which the classificatrio criterion is based on the point of interference of the mechanism of action of the different stages of the synthesis of the DNA, transcription and transduo. However, the authors consider this arbitrary classification, therefore, for example, the hormonais agents, among others, are not classified in such a way (Martins et al., 2002). In fact, diverse mechanisms exist that are involved in the evolution of a normal cell for a potentially malignant cell, but most of them intervenes with cellular division e, thus, the knowledge of the cellular cycle or its mechanisms it is important so that it has the understanding of the etiology of the cancer (Sources et al.