Final answer:
An enlarged, painless testicle can indicate testicular cancer, a condition that may present as a lump or swelling in the testis. Diagnosis involves physical exams and tests such as ultrasounds and blood tests for tumor markers. Early detection often leads to successful treatment.
Step-by-step explanation:
An enlarged, painless testicle in an adolescent or adult male may be indicative of testicular cancer, a condition that occurs when cells within the testes grow uncontrollably, forming a lump known as a tumor. Testicular cancer is most commonly diagnosed in males between the ages of 20 to 39 and is more prevalent among those of European descent. It often presents as a lump or swelling in one testis and may be associated with fluid in the scrotum and a feeling of heaviness. While a painful lump is possible, testicular cancer lumps are often painless.
Diagnosis typically involves a physical exam and tests such as an ultrasound, which ascertains the size and characteristics of the lump, as well as blood tests for tumor-marker proteins. Unlike prostate cancer, a biopsy is not recommended for diagnosing testicular cancer, to prevent the potential spread of cancer cells. If detected early, testicular cancer can often be treated successfully with surgery and possibly followed by radiation therapy or chemotherapy.
It is also important to note that other conditions, such as epididymitis or orchitis, can cause swelling and pain in the scrotum. However, these are usually caused by bacterial infections and present additional symptoms like redness, warmth, and discomfort during urination, differentiating them from signs of testicular cancer.