Oncologist. 1998;3(2):129-130.  

Molecular Action and Clinical Relevance of Aromatase Inhibitors.

Murphy MJ Jr.

AlphaMed Press, Miamisburg, Ohio, 45342-3758, USA. mjm@alphamed press.com

BREAST CANCER: HIGH PREVALENCE AND RISING INCIDENCE: Breast cancer is the most
common form of cancer among women in Europe, North and South America and
Australasia; approximately 1 in 10 women in Western countries will develop
breast cancer during their lifetime. It is estimated that the disease will
affect five million women worldwide over the next decade, and the incidence of
breast cancer is increasing on average by about 1% per year in industrialized
countries and at a greater rate in developing countries. COMPLEX ETIOLOGY:
Although the specific etiology of breast cancer remains unknown, a number of
factors are recognized which increase a woman's risk of developing the disease.
Genetic predisposition, or family history of breast cancer, is known to be
responsible for 5% of all cases. However, the variation in incidence throughout
populations, and changes relating to population migration and adoption of
altered lifestyles, all point to the critical importance of nongenetic
determinants. Such factors include early menarche, late menopause, late age at
birth of first child or nulliparity, a history of benign breast disease, and
diet. There is also evidence that hormones play a major role in the etiology of
breast cancer, with the risk of developing malignancies related to the
cumulative exposure of the breast to estrogen and progesterone, which stimulate
the growth of tumor cells. TREATMENT FOR EARLY BREAST CANCER: SURGERY -/+
ADJUVANT THERAPY: At the time of diagnosis, approximately 50% of patients will
be diagnosed with early breast cancer. This proportion is increasing as a
consequence of the introduction of early detection programs. Surgery remains the
primary treatment for early breast cancer, and the frequency of radical
mastectomy has been replaced by breast conserving surgery. After surgery, other
therapeutic modalities such as radiation, chemotherapy or endocrine therapy may
be given in the adjuvant setting. Surgical cure rates vary for patients with
early breast cancer; the US figure is approximately 40%, and there are no
definitive means to predict those who will be cured and those who will have
recurrent disease. As a result, following primary surgical treatment, adjuvant
therapy is usually recommended to destroy any remaining cancer cells at the
primary site, to control micrometastases and to prolong disease-free survival,
with the