Finding a mass or “small ball” in the testicles naturally causes significant concern. While it is understandable to consider the most serious possibilities, most masses found in the scrotum are not cancerous. This article explores potential causes, from the most common and benign to the more serious, to provide context. However, this information is for educational purposes only and is not a substitute for professional medical advice. Any new or unexplained lump, swelling, or change requires immediate evaluation by a healthcare provider, such as a general practitioner or a urologist, for an accurate diagnosis and appropriate care.
Common Non-Cancerous Causes of Testicular Lumps
The vast majority of testicular lumps are benign and originate not from the testicle itself, but from surrounding structures, such as the epididymis or the spermatic cord. One common finding is a spermatocele, often called an epididymal cyst. This is a fluid-filled sac that develops in the epididymis, the coiled tube located behind the testicle that stores and transports sperm.
A spermatocele typically feels like a smooth, soft, and well-circumscribed lump, separate from the testicle, and is usually painless. When examined, this fluid-filled mass will often transilluminate (light passes through it), which is a helpful initial sign that the mass is not solid.
Another frequent cause of scrotal swelling is a hydrocele, which is an accumulation of clear fluid within the tunica vaginalis, the thin sac surrounding the testicle. A hydrocele generally causes a soft, non-tender fullness around the testicle, sometimes making the scrotum feel heavy. Like a spermatocele, this fluid collection typically transilluminates when examined.
A varicocele involves the abnormal enlargement and dilation of the pampiniform plexus, the network of veins that drain the testicle. While not always a distinct “small ball,” a varicocele may present as a soft lump or swelling above the testicle, often described as feeling like a “bag of worms.” These lumps are usually more noticeable when standing or straining and frequently occur on the left side due to anatomical differences.
Inflammation or infection of the epididymis, known as epididymitis, can manifest as a tender, painful lump or swelling. When inflamed, the epididymis becomes swollen, warm, and highly sensitive to touch. This condition often has a gradual onset and may be accompanied by fever, pain during urination, or urethral discharge, especially when caused by a bacterial infection.
Recognizing Testicular Cancer
While most testicular masses are benign, the most serious possibility is testicular cancer, which is the most common cancer in males aged 15 to 34. A cancerous mass usually exhibits characteristics distinct from benign masses. It is typically a firm, hard lump or an area of firmness located within the testicle itself, rather than being separate in surrounding structures.
An early-stage cancerous tumor can be small, but it feels solid to the touch, unlike the soft or fluid-filled nature of a spermatocele or hydrocele. A cancerous lump is often painless, meaning discomfort is not a reliable way to differentiate benign from malignant conditions. The first sign of cancer may simply be an unexplained enlargement of the testicle, a change in how it feels, or a sensation of heaviness in the scrotum.
The strongest established risk factor for testicular cancer is a history of cryptorchidism, or an undescended testicle. If the testicles fail to descend from the abdomen into the scrotum before birth, the risk of cancer is significantly elevated, even after corrective surgery. A family history of the disease, particularly in a brother or father, also increases personal risk. The disease is most prevalent in young adults, with the highest incidence occurring between the ages of 15 and 45.
What to Expect During Diagnosis and Next Steps
Upon discovering any new lump or change, the immediate step is to schedule an appointment with a healthcare provider, such as a urologist or general practitioner. A delay in evaluation can complicate the management of any condition, especially if it is malignant. The diagnostic process begins with a thorough physical examination, where the doctor assesses the location, size, and consistency of the mass and determines if it is attached to the testicle or separate from it.
The primary diagnostic tool used is the scrotal ultrasound. This non-invasive imaging test uses sound waves to create a detailed picture of the internal structures. It allows the doctor to determine whether the mass is solid or fluid-filled, and whether it is located inside the testicle (intratesticular) or outside it (extratesticular). A mass found inside the testicle is significantly more likely to be cancerous, while those outside are overwhelmingly benign.
If the ultrasound suggests a solid mass or raises suspicion of cancer, the doctor will likely order blood tests for tumor markers. These markers are proteins produced by certain cancer cells. Elevated levels of substances like alpha-fetoprotein (AFP), human chorionic gonadotropin (beta-hCG), and lactate dehydrogenase (LDH) can support a diagnosis of testicular cancer.
For benign conditions, such as a small spermatocele or hydrocele that is not causing discomfort, the usual course of action is monitoring. If a bacterial infection like epididymitis is diagnosed, it is typically managed with antibiotics. If cancer is strongly suspected, the definitive next step is surgical removal of the affected testicle, which provides the tissue sample needed for a final pathology diagnosis.