Testicular cancer is a relatively rare but highly treatable malignancy that develops in the testicles, the male reproductive organs responsible for producing sperm and testosterone. It typically presents as a painless lump or swelling in one of the testicles. Other symptoms may include a feeling of heaviness in the scrotum, discomfort or pain in the testicle or scrotum, enlargement of the breast tissue (gynecomastia), and back pain. Risk factors for testicular cancer include undescended testicle, family history of the disease, age (most commonly affects young men aged 15 to 35), and certain genetic conditions. Diagnosis involves a combination of physical examination, ultrasound imaging, blood tests (including tumor markers such as alpha-fetoprotein and beta-human chorionic gonadotropin), and surgical biopsy if necessary. Treatment options depend on the type and stage of the cancer but may include surgery, radiation therapy, chemotherapy, or a combination of these approaches. With early detection and prompt treatment, the prognosis for testicular cancer is generally excellent, with high cure rates. Regular self-examinations and medical check-ups are important for early detection and effective management of testicular cancer.