A 40-year-old female has a 1.5 cm well-circumscribed mass noted on mammography. What is the most appropriate next procedure?

In a situation where a 1.5 cm well-circumscribed mass is identified on mammography, the most appropriate next step is fine needle aspiration. This procedure allows for the extraction of a sample of cells from the mass, which can then be examined cytologically to determine whether the mass is benign or malignant. Given that the mass is palpable and well-defined, fine needle aspiration is a minimally invasive option that can provide important diagnostic information.

Fine needle aspiration is especially useful in this context because it aids in evaluating solid masses and can often guide treatment decisions based on the nature of the cells retrieved. If the mass is determined to be benign, further surgical intervention may not be necessary; if malignant, appropriate oncological treatment can be initiated.

Other options like genetic testing (BRCA 1 and BRCA 2), serum CA-125 measurement, or radiation therapy are not appropriate next steps immediately following the detection of a mass on mammography. Genetic testing may be indicated in women with a strong family history of breast cancer but is not a diagnostic procedure for a specific mass. Similarly, serum CA-125 is a tumor marker used primarily in ovarian cancer screening and monitoring, not for breast masses. Radiation therapy is a treatment modality used after a diagnosis of