“Endocrine therapies: the point of view of the oncologist”: this is the title of the speech by Dr. Agnese Losurdo, specialist in Medical Oncology in Humanitas, during Mamazone 2017, the seventh edition of “Paziente Diplomata”, a day dedicated to women with and without breast cancer, organized by Humanitas last October.
The doctor attempted to tell patients how to balance the benefits and side effects of endocrine treatments.
Drugs for Endocrine Therapies
“Endocrine therapy works by interacting with the hormonal system; this is the first so-called intelligent therapy because it has a targeted action only on cells that have hormonal receptors (estrogen and progestins) on their surface,” explained the doctor.
These drugs prevent estrogen from reaching neoplastic mammary cells, thus slowing their development, or reduce the amount of estrogen produced by the body in order to try to decrease the risk of relapse.
“There are three classes of drugs to refer to: SERM or selective modulators of the estrogen receptor, so called because depending on the target organ they have pro-estrogenic or anti-estrogenic effects (as in the case of breast cancer); aromatase inhibitors, which inhibit the aromatase enzyme present in high concentration in body fat and similar LHRH, drugs that mimic LHRH, a hormone produced at pituitary level, and that through a complex mechanism are able to block the ovarian production of sex hormones.
Benefits of Endocrine Therapy
“Since the 1990s, SERMs (such as tamoxifen) have been regularly used for 5 years after surgery in patients with estrogen receptors and/or positive progestins, and there is a proven advantage in significantly improving disease-free survival and reducing the number of relapses of disease both locally and remotely. Aromatase inhibitors have two subcategories: irreversible steroidal inhibitors and reversible non-steroidal inhibitors; these drugs have been approved for both adjuvant and metastatic phases because of their proven efficacy. Similar LHRHs have allowed us to abandon the practice of surgical ovarian removal that was used in the past in women who had to take hormone therapy,” said Dr. Losurdo.
Endocrine therapies beyond 5 years
“In general, patients with positive hormonal receptors have a low risk of recurrence, a risk that, although low, remains long after surgery. Numerous randomized trials have evaluated the continuation of endocrine therapy with tamoxifen (SERM) or aromatase inhibitor for up to ten years, highlighting a benefit in terms of reducing the risk of recurrence of local and remote disease. Patients who benefit most from prolonged endocrine therapy are those at high risk, for example, with lymph nodes that are positive for surgical diagnosis.
It is therefore essential, in assessing the continuation of endocrine therapy after the fifth year, to balance the potential benefit (as shown by studies) with subjective tolerance to the therapy and with the side effects that have occurred in previous years. Dr. Losurdo also explained which side effects are the most common and which strategies can be adopted to combat them.
How to find a balance?
“In choosing endocrine therapy and its duration, the potential benefits in terms of reducing relapses and prolonging disease-free survival must be well balanced with the inherent risk of recurrence and the weight of any side effects. The decision must be the result of careful counseling between the doctor and the patient, and the patient must have all the tools to be able to participate consciously in the choice of the type and duration of endocrine therapy,” concluded the specialist.
Watch the full intervention of Dr. Losurdo, click here
