If a patient has an elevated PSA or palpable nodule, what is the next step in diagnosis?

In cases of elevated prostate-specific antigen (PSA) levels or a palpable nodule, the next most appropriate step in diagnosis is a biopsy. While transrectal ultrasound (TRUS) can be utilized in the process and aids in guiding the biopsy, it is not a definitive diagnostic step on its own. A biopsy is necessary to obtain tissue for histological examination, allowing for the diagnosis of prostate cancer or other conditions.

Transrectal ultrasound is typically performed to visualize the prostate and may help in targeting specific areas for biopsy, but it does not provide a diagnosis without concurrent biopsy. Performing a biopsy is crucial because it confirms or rules out malignancy, which is the critical information needed for further management decisions.

In contrast, imaging modalities such as CT scans or bone scans may be warranted after a diagnosis of prostate cancer is established, particularly for staging or evaluating potential metastases, but they are not first-line diagnostic tools for evaluating PSA elevations or suspicious nodules. Therefore, a biopsy represents the correct step in the diagnostic process following an elevated PSA or palpable nodule.