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KEY CLINICAL UPDATES IN CARCINOMA OF THE FEMALE BREAST
In 2020, the FDA approved neratinib (in combination with capecitabine) and margetuximab, a monoclonal antibody similar to trastuzumab that is designed to improve the antibody dependent cellular cytotoxicity mechanism of action when used with chemotherapy.
In 2020, pembrolizumab, a second immune checkpoint inhibitor, was FDA approved for use in patients with PD-L1 positive disease in combination with chemotherapy (taxane or gemcitabine/carboplatin) based on results from the KEYNOTE 355 trial showing an improved median progression-free survival with the addition of this antibody to standard chemotherapy.
Sacituzumab govitecan (TRODELVY) is the first antibody drug conjugate approved for triple negative breast cancer.
The phase 3 confirmatory trial, ASCENT, demonstrated that sacituzumab govitecan is associated with a statistically significant improvement in progression-free and overall survival when compared to single-agent chemotherapy in patients with triple negative breast cancer who had received at least two prior lines of standard chemotherapy for metastatic disease.
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ESSENTIALS OF DIAGNOSIS
Risk factors: Age, nulliparity, childbirth after age 30, family history of breast cancer or deleterious mutations (BRCA1, BRCA2, or others), and personal history of breast cancer or some types of proliferative conditions.
Early findings: Mammographic abnormalities and no palpable mass, or single, nontender, firm to hard mass with ill-defined margins.
Later findings: Skin or nipple retraction; axillary lymphadenopathy; breast enlargement, erythema, edema, pain; fixation of mass to skin or chest wall.
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INCIDENCE & RISK FACTORS
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Breast cancer will develop in one of eight American women. Next to skin cancer, breast cancer is the most common cancer in women; it is second only to lung cancer as a cause of death. In 2020, there were approximately 279,100 new cases and 42,690 deaths from breast cancer in the United States. The highest rates of death are in non-Hispanic Black women in the United States. Worldwide, breast cancer is diagnosed in approximately 2.2 million women, and about 684,996 die of breast cancer each year, with the highest rates of diagnosis in Australia/New Zealand, Europe, and North America and lowest rates in Eastern/Middle Africa and South Central Asia. These regional differences in incidence are likely due to the variable availability of screening mammography as well as differences in reproductive, nutrition, and hormonal factors. In western countries, incidence rates decreased with a reduced use of postmenopausal hormone therapy and mortality declined with increased use of screening and improved treatments. In contrast, incidence and mortality from breast cancer in many African and Asian countries have increased as reproductive factors have changed (such as childbirth after age 30) and as the incidence of obesity has risen.
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The most significant risk factor for the development of breast cancer is age. A woman’s risk of breast cancer rises rapidly until her early 60s, peaks in her 70s, and then declines. A significant family history of breast or ovarian cancer imparts a high risk of developing breast cancer. Germline mutations in ...