However, some experts [27] suggest that MMR vaccine can be avoided in the case of children who have received very prolonged and powerful chemotherapy (for whom live vaccines can be dangerous) and who live in an area in which more than 90% of the total pediatric population has been vaccinated against MMR, because they will probably

be protected by herd immunity. In the case of inactivated or recombinant vaccines, their optimal safety and tolerability means that they could be administered OSI-744 price earlier if this is epidemiologically justified (influenza vaccine is a paradigmatic example) [60], [61], [62], [63], [64], [65], [66], [67], [68] and [69]. However, it is impossible to define the best approach for children who have received some but not all of the doses of a specific vaccine at the time of the diagnosis of cancer because of the lack of appropriate data. It can only be suggested that they should perhaps be given all of the doses usually needed to confer protection, regardless of those they have already received. Unfortunately, data concerning compliance with recommendations of children with cancer clearly indicate that only a minority of these patients receive adequate protection against vaccine-preventable diseases [67]. Several attempts to increase compliance have been made but even if most of them are

effective in increasing the number of children that receive recommended vaccines, none of them is able to reach all Apoptosis inhibitor this high-risk population [68]. Regarding immunisation in children with cancer, for some vaccines there is enough evidence to design good recommendations for protecting these patients against vaccine-preventable diseases without any risk of poor immune response or adverse events. This is particularly true for old vaccines based on inactivated components when they have to be administered to children who have completed cancer therapy. However, more information is needed about children who have received only some of the doses of the usually recommended vaccines. Moreover, further Ketanserin studies

are required concerning the use of pneumococcal and meningococcal conjugate vaccines, and there is an urgent need for studies of when and how to use the new vaccines (e.g. HPV). Only new data will make it possible to draw up evidence-based recommendations to ensure that all these high-risk patients are adequately protected against infectious diseases. Finally, it is mandatory that all the children with cancer receive recommended vaccines as soon as possible. Consequently, because at the moment the use of vaccines in these patients is significantly lower than expected, adequate measures to increase compliance as well as communication with these children and their families have to be implemented. This paper was supported in part by a grant from the Italian Ministry of Health (Bando Giovani Ricercatori 2007).