How Doctors Distinguish Prostate Cancer From Other Prostate Problems

Screening with the prostate-specific antigen (PSA) test can detect early-stage prostate cancer while it is still asymptomatic. However some men are only diagnosed after symptoms appear. To understand how doctors differentiate prostate cancer from benign prostate conditions we spoke with Dr Marc B. Garnick, Gorman Brothers Professor of Medicine at Harvard Medical School and Beth Israel Deaconess Medical Center.

Symptoms of Early-Stage Prostate Cancer

Most men diagnosed with prostate cancer—even those with advanced disease—do not present with symptoms. When symptoms occur in early-stage disease they usually affect urination and are known as lower urinary tract symptoms (LUTS) including:

Urinary frequency
Urgency
Difficulty starting or stopping the urine stream
Nocturia (waking at night to urinate)
Sensation of incomplete bladder emptying

LUTS may develop if a tumor obstructs the urethra or if the prostate presses against the bladder, reducing its capacity.

Other Common Causes of Urinary Symptoms

More often urinary symptoms arise from noncancerous conditions such as:

Benign prostatic hyperplasia (BPH), a natural age-related enlargement of the prostate
Prostatitis, inflammation of the prostate and surrounding tissues
Bladder problems, often indicated by burning sensations during urination

Men with any of these symptoms should be evaluated by a doctor.

Diagnostic Evaluation

After ruling out prostatitis and bladder disease the focus shifts to distinguishing between prostate cancer and BPH. Key steps include:

AUA Symptom Score questionnaire to quantify LUTS
Digital rectal examination (DRE) to assess prostate size and texture

Findings suggestive of BPH include a symmetrically enlarged prostate. Asymmetry or a hard nodule warrants referral to a urologist. Although DREs are performed less frequently today many experts consider them crucial.

Complications and Management of BPH

BPH can lead to serious complications such as kidney failure or acute urinary retention. Treatment typically begins with medications that ease urination and lower PSA levels. After six weeks PSA is retested. Persistently elevated PSA often prompts an MRI of the prostate. A normal MRI with PSA proportional to prostate size may allow continued monitoring without immediate biopsy.

Advanced Prostate Cancer Symptoms

Even advanced prostate cancer can be asymptomatic. When metastases reach the bones men may experience persistent back or shoulder pain. Worsening pain despite treatment should prompt imaging such as X-ray or MRI. Bone pain of this nature is less common in prostate cancer than in other cancers unless the disease is widespread.