A 59-year-old man is being evaluated for markedly elevated prostate-specific antigen levels. He has no bone pain or urinary symptoms. The patient has no chronic medical conditions or surgical history. His father died of prostate cancer. Vital signs are normal. Digital rectal examination reveals an indurated prostate with no palpable nodules. The remainder of the examination is normal. Prostate biopsy is planned. Which of the following is the best way to obtain a diagnosis in this patient?

Question

A 59-year-old man is being evaluated for markedly elevated prostate-specific antigen levels.  He has no bone pain or urinary symptoms.  The patient has no chronic medical conditions or surgical history.  His father died of prostate cancer.  Vital signs are normal.  Digital rectal examination reveals an indurated prostate with no palpable nodules.  The remainder of the examination is normal.  Prostate biopsy is planned.  Which of the following is the best way to obtain a diagnosis in this patient?

Quizplus · Accepted Answer

11ec160b_39a3_308d_9249_239b11d79830_MD0001_00 The prostate is a walnut-sized gland that encases the urethra and vas deferens. It abuts the urinary bladder superiorly and the rectum posteriorly and is composed of 3 distinct zones: The peripheral zone is largely glandular and is the site of >85% of prostate adenocarcinoma. Because this zone borders the rectum, patients with suspected prostate cancer generally undergo transrectal ultrasound-guided biopsy. In this procedure, transrectal ultrasound identifies the borders of the prostate and suspicious hypoechoic lesions; multiple core biopsies (usually 10-12) are then obtained from random locations within the apical and far-lateral prostate (peripheral zone). Because the distal urethra passes through only a small portion of the peripheral zone, prostate cancer does not typically present with urinary symptoms (eg, voiding difficulty, hematuria). The central zone surrounds the ejaculatory duct. This zone is primarily composed of stroma elements; prostate cancer rarely develops in this area. The transition zone surrounds the urethra. This is the primary site of benign prostatic hyperplasia. Because only 10% of prostate cancers arise in this region, cystoscopy approaches (via the urethra) are not typically used to sample the prostate for cancer (Choices A and B). (Choice C) Fine-needle aspiration is not recommended for the diagnosis of prostate cancer because tissue architecture is lost during sampling. Transperineal core biopsies are occasionally used to diagnose prostate cancer in men who cannot tolerate the transrectal approach. (Choice E) The diagnosis of prostate cancer requires multiple core biopsies to obtain adequate sampling of the prostate. A single biopsy would dramatically increase the risk of a false negative result. Furthermore, the central portion of the gland is less likely to develop prostate cancer than the peripheral portion. Educational objective: Most prostate cancer arises in the peripheral zone of the gland, which abuts the rectum. Therefore, prostate biopsies are primarily obtained via the transrectal approach; multiple random core samples of the prostate are typically taken. Because only a small part of the peripheral zone encases the distal urethra, patients with prostate cancer do not typically present with urinary symptoms.

A 59-Year-Old Man Is Being Evaluated for Markedly Elevated Prostate-Specific