Genitourinary (GU) cancer refers to a diverse group of malignancies that affect the organs of the urinary system in both men and women, as well as the male reproductive organs. These cancers include frequently diagnosed malignancies, such as prostate and bladder cancers. Because these organs are functionally and anatomically related, the cancers that arise within them are often managed by the same medical specialty, urology, leading to their grouping under the term genitourinary.
Defining the Genitourinary System and Malignancies
The genitourinary system is a combined term encompassing the urinary tract and the male genital tract, organs that share close anatomical proximity and functional overlap. The urinary system is responsible for filtering blood and excreting waste, involving the kidneys, the ureters, the bladder, and the urethra. In males, the reproductive organs—specifically the prostate gland and the testes—are also included in this grouping because the urethra serves as the final pathway for both urine and semen.
Cancers arising in this system are termed genitourinary malignancies. The specific location of the cellular malfunction dictates the type of cancer, leading to distinct diseases of the kidney, bladder, prostate, and testes, which are often treated by urologic oncologists.
Primary Cancers of the Urinary Tract
Cancers of the urinary tract primarily include cancers of the kidney and the bladder. Renal cell carcinoma (RCC) is the most common form of kidney cancer, typically beginning in the lining of the renal tubules. Because the kidneys are deep within the body, RCC often grows silently and is frequently discovered incidentally during imaging scans performed for other medical reasons.
Bladder cancer most commonly arises in the urothelial cells, also known as transitional cells, that line the inside of the bladder, ureters, and renal pelvis. Exposure to certain chemicals is a significant risk factor for bladder cancer due to the bladder’s function of temporarily storing urine. Chemicals in tobacco smoke are absorbed, filtered by the kidneys, and highly concentrated in the urine. The bladder lining is exposed to these potent carcinogens, leading to cellular damage. Smoking is estimated to contribute to approximately half of all bladder cancer cases.
Cancers of the Male Reproductive Organs
Cancers of the male reproductive organs, specifically the prostate and the testes, constitute a major category of genitourinary malignancies.
Prostate Cancer
Prostate cancer is the most common genitourinary cancer overall, developing in the walnut-sized gland located just below the bladder. The prostate produces the fluid that nourishes and transports sperm. Prostate cancer is often characterized by its relatively slow-growing nature, though more aggressive forms exist. Detection frequently relies on screening methods such as the Prostate-Specific Antigen (PSA) blood test, which measures a protein produced by the gland. Elevated PSA levels can indicate cancer, though they can also be raised by non-cancerous conditions.
Testicular Cancer
Testicular cancer most often affects younger men, typically between the ages of 15 and 35. The vast majority of these cancers originate in the germ cells, the sperm-producing cells within the testes. These germ cell tumors are broadly classified into two main types: seminomas and non-seminomas.
Seminomas are generally slower-growing and tend to be more sensitive to radiation therapy, often occurring in men in their 40s and 50s. Non-seminomas, which include subtypes like embryonal carcinoma, are typically more aggressive and spread more rapidly. Despite the aggressive nature of some forms, testicular cancer is considered one of the most curable solid tumors, especially when detected early.
Recognizing Common Warning Signs and Detection Methods
Symptoms of genitourinary cancers can be vague or absent in early stages. The presence of blood in the urine, known as hematuria, is a common sign for cancers of the urinary tract, including bladder and kidney cancers. Other urinary changes may include a frequent or urgent need to urinate, pain during urination, or a weak urine stream.
For reproductive system cancers, a painless lump or swelling on a testicle is the most common sign of testicular cancer. Prostate cancer symptoms, if present, may include difficulty starting or stopping urination or pelvic discomfort. Advanced disease in any organ may manifest as unexplained back or side pain, fatigue, or a palpable mass.
When a genitourinary malignancy is suspected, a combination of methods is used to confirm a diagnosis:
- Imaging techniques like computed tomography (CT) scans, magnetic resonance imaging (MRI), and ultrasound are used to visualize the organs and identify tumors.
- Specific blood tests, such as the Prostate-Specific Antigen (PSA) test for prostate cancer, can provide initial clues.
- For bladder cancer, urine cytology involves examining a urine sample under a microscope for abnormal cells.
- Cystoscopy allows a doctor to look directly inside the bladder.
- Ultimately, a biopsy—the removal of a tissue sample for laboratory analysis—is typically required to definitively diagnose cancer.