Which method is considered definitive for diagnosing a fibroadenoma?

The definitive method for diagnosing a fibroadenoma is through core biopsy or excision. This approach allows for the collection of tissue samples that can be examined histologically. By obtaining a sample, it is possible to analyze the cellular characteristics of the mass, confirming its benign nature and distinguishing it from other breast conditions, such as breast cancer. Core biopsies can provide a more accurate diagnosis compared to imaging studies or physical exams, which may raise suspicion but do not yield definitive results.

Mammography can help identify the presence of a fibroadenoma, but it does not provide tissue for histological examination, which is crucial for a definitive diagnosis. Physical examination may suggest a fibroadenoma based on the consistency and mobility of a breast lump but lacks the specificity needed. Ultrasound can assist in characterizing the lesion and evaluating its features, but like mammography, it cannot confirm the diagnosis without a tissue sample. Therefore, core biopsy or excision is the gold standard for definitive diagnosis of a fibroadenoma.