@katrina123
Since you are starting out in your exploration on this very complex subject, I hope that you will allow me to give you some hints on how to proceed. Firstly, learn everything you can about your particular diagnosis (there are many types of breast cancers and people have individual pathology characteristics like whether or not the tumor was hormone receptor positive/negative/both or HER2 positive or negative, whether there is a genetic link involved through family history, etc. When you are ready to read various studies on your particular situation, look for current articles (the science changes rapidly), and studies based on large cohorts. (I particularly like what they call meta-analyses where similar studies are combined.) Learn the lingo used. For example, a lot of what is written about aromatase inhibitors and selective estrogen receptor modulators discusses their use in terms of the risk of recurrence and overall mortality. You want to focus on the former. The notes on overall survival have a gzillion factors (like age, whether the patient has diabetes or heart disease or other comorbidities, etc.), and our survival depends more on those factors than anything else. The reason we take AIs or SERMs is basically to prevent recurrence of our cancer (somewhere in our bodies), and AIs and SERMs have a good track record of preventing recurrence while we are taking them, despite the side effects we may encounter. (Another bonus of AIs is that researchers now believe that they may have somewhat of a protective effect up to five years after we stop our 5-7 year program of taking them!) Make copies of the studies which interest or trouble you and discuss them with your oncologist, asking about why your current treatment is appropriate in light of the studies you are reading. In the end, the decision ultimately will be yours once you feel that you are sufficiently informed.

The five-year old article which you cited is focused on a specific subgroup of high-risk patients in a particular Swiss study, and discusses whether there is a way to use AIs and SERMs as a preventive tool in healthy women versus a treatment tool for those with breast cancer... not something which is going to be helpful in your exploration in my view.