A hematocele is a collections of blood in a body cavity or potential space. The term most commonly refers to the collection of blood in the tunica vaginalis around the testes, known as a scrotal hematocele. Hematoceles can also occur in the abdominal cavity and other body cavities. Hematoceles are rare, making them harder to diagnose and treat. They are very common especially as slowly growing masses in the scrotum usually in men older than 50 years. A scrotal mass is a lump or bulge that can be felt in the scrotum. The scrotum is the sac that contains the testicles. A scrotal mass can be noncancerous (benign) or cancerous (malignant). Benign scrotal masses will include hematocele which is a blood collection in the scrotum. A scrotal hematocele is also called a hemoscrotum (or haemoscrotum in British English). Scrotal masses are abnormalities in the bag of skin hanging behind the penis (scrotum). The scrotum contains the testicles and related structures that produce, store and transport sperm and male sex hormones. Hemoscrotum can follow trauma (such as a straddle injury) or can be a complication of surgery. It is often accompanied by testicular pain. It has been reported in patients with hemophilia and following catheterization of the femoral artery. If the diagnosis is not clinically evident, transillumination (with a penlight against the scrotum) will show a non-translucent fluid inside the scrotum. Ultrasound imaging may also be useful in confirming the diagnosis. In severe or non-resolving cases, surgical incision and drainage may be required. To prevent recurrence following surgical drainage, a drain may be left at the surgical site. Signs and Symptoms Variation in signs and symptoms will depend on the abnormality present and medical history. Variation exists in hematoceles due to the location of the lesion and onset of the hematocele. It is important to seek emergency medical care if developing sudden pain in the scrotum to avoid damage to the testicle that can be permanent. The signs and symptoms listed below are relating to hematoceles and associated conditions that can be due to other causes such as testicular cancer or testicular torsion: Unusual lump Sudden pain Dull aching pain or feeling heavy in the scrotum Pain radiating throughout the groin, abdomen, or lower back Tender, swollen, or hardened testicle Tender, swollen, or hardened epididymis, the soft, comma-shaped tube above and behind the testicle that stores and transports sperm Swelling in