The benefits of adjuvant tamoxifen are indisputable; however, its optimal duration is an issue still under discussion. The Oxford Overview analysis, based on 35,000 patients, concludes that five-year treatment is clearly superior to 0-2 years of treatment. Whether a longer period of therapy, namely 10 years, can yield better results is still unknown as the number of patients enrolled in clinical trials (8000) and the median follow-up are still insufficient. Furthermore, the benefits must always be balanced with its potential hazards, namely the increased risk of endometrial cancer that could be related to the duration of therapy. This study investigated the effects of drug treatment after relapse or surgical/radiological treatment.