Use of trastuzumab for breast cancer: the impact of age.

Indication for the use of trastuzumab was given in Italy in 2000 for the treatment of HER-2 metastatic breast cancer and in2006 for early stage breast cancer. Information on trastuzumab use and on its possible variation with age in Italy is however limited. Usinghealth care administrative databases, we evaluated the prevalence of the use of trastuzumab, and the probability for administrationsince the first hospitalization for breast cancer in various age groups, in two series of Italian women diagnosed with breast cancer in theLombardy region (2004-2009) and in the Palermo district. The rate between trastuzumb users and patients with a hospitalization forbreast cancer increased from 2.9% in 2004 up to 17.2% in 2009 in Lombardy. Patients aged <65 years were more frequent users (9.6%)compared to those aged 75 years (1.3%). Similarly, in the Palermo district the proportion of users increased from 10.6% in 2006 to28.5% in 2008, with subjects aged <65 years more frequently using trastuzumab (19.1%), than subjects aged 75 years (6.2%). The rateratio between younger and older patients decreased over time in both settings (from 15 in 2004 to 10.2 in 2006, and 5.2 in 2009 inLombardy, and from 4.0 in 2006 to 2.3 in 2009 in Palermo district). The proportion of breast cancer patients using trastuzumab increasedover time both in Lombardy and in Palermo District, though geographical differences persisted. Younger breast cancers patients weremore likely to receive a trastuzumab treatment than elderly ones.