Long-term results on trastuzumab (T) in elderly patients (EP) with locally advanced or metastatic HER2-positive breast cancer (BC).

624 Background: In a prospective, non-interventional observation study, routine T treatment in advanced, HER2-positive BC was evaluated in a total of 1,843 patients (pts) enrolled between 2001 and 2010. With a follow-up duration of up to more than 11 years (y), this report focuses on the relatively large subgroup of EP (> 65 y). Methods: Pts were enrolled by 223 institutions in Germany. HER2-positivity was defined as 3+ staining in immunohistochemistry or a positive fluorescence in situ hybridization (FISH) test in case of 2+ staining. All types of pretreatments were acceptable. Detailed information on study treatment, its safety and the course of disease was collected for at least 1 y. Thereafter, long-term outcome data were additionally retrieved at specified follow-up time points. Results: The median age of the total observation group was 59.5 y (range: 21–95), with 505 pts being > 65 y (28%), 257 pts > 70 y (14%), and 58 pts even 80 y or older (3%). The percentage of EP constantly increased over the 1...