Is fulvestrant safe and effective to treat male breast cancer?

This paper evaluated the safety and effectiveness of fulvestrant (Faslodex) in men with breast cancer.

Male breast cancer is uncommon, and hence there are a lack of clinical trials and treatment recommendations specifically for men. While tamoxifen (Soltamox, Nolvadex) is regarded as the gold standard of adjuvant treatment (additional treatment given after main treatment), not everyone responds to tamoxifen. Fulvestrant has been suggested as an alternative. Fulvestrant works by blocking the activity of estrogen receptor, which encourages growth and replication of cells.  

The authors analyzed 5 studies studying fulvestrant. 86.7% of patients had invasive ductal carcinoma (cancer that has spread to the milk ducts). All patients had estrogen receptor positive cancer (estrogen receptor present). Fulvestrant was given as a first or second treatment in 40% of patients. Fulvestrant was given as a third treatment or beyond in 60% of patients. The dose of fulvestrant given was 250 mg monthly following an initial dose of 500 mg. 79.0% of patients had visceral metastases (spread of cancer to internal organs such as the liver and lungs) at administration of fulvestrant. 66.7% of patients' breast cancer had spread to the bones.

26.1% of patients had a decrease in size of tumour. 47.8% of patients had no change in tumour size. 26.1% of patients had an increase in tumour size. The average progression-free survival (period of time without worsening of disease) was 5 months. With regards to adverse events (undesired event caused by treatment), 18.2% of patients reported hot flashes (feeling hot over the upper part of the body). 

The authors concluded that fulvestrant is a safe and effective treatment option for hormone receptor-positive metastatic male breast cancer patients. 

Studies analyzed were limited and further studies are warranted.