Cancer is a leading cause of morbidity and mortality worldwide, with increasing incidences in all countries regardless of their economic status . It is estimated that in 2012 there were 14 million new cases of cancer , and 8.2 million related deaths . In the case of breast cancer, one of the most frequently diagnosed in women, incidence rates vary greatly worldwide, ranged between 19.3 and 89.7 per 100 000 women, and in most of the developing regions the incidence rates are below 40 per 100,000 , representing 6.35% of all cancer-related deaths .
Trastuzumab is a humanized monoclonal antibody used to block the action of the HER2 oncogene in those cancers classified as HER2 positive . In these cases, the disease typically has a worse prognosis . Trastuzumab was first approved in 1998, and the NICE approved its use in a guideline published in 2006, “given at 3-week intervals for 1 year or until disease recurrence (whichever is the shorter period), is recommended as a treatment option for women with early-stage HER2-positive breast cancer following surgery, chemotherapy (neoadjuvant or adjuvant) and radiotherapy (if applicable)” .
In 2012, Moja et al.  performed a meta-analysis with 11,991 patients, reporting that the use of this drug represents a statistically significant improvement in overall survival and disease-free survival. As adverse events, an increased risk in congestive heart failure and a decline in left ventricular ejection fraction were detected.
Click here to view the full article in Journal of Comparative Effectiveness Research.