Finding a lump in the perineum—the area of skin and tissue between the anus and the vulva or scrotum—is naturally a cause for concern. This region is susceptible to a variety of growths, ranging from common skin issues to complex infections and masses. While many perineal lumps are benign, determining the cause requires a medical evaluation. This information provides a general overview of possible causes and is not a substitute for professional medical advice.
Superficial Skin Issues and Benign Cysts
Lumps often originate from the skin’s surface structures. One common cause is folliculitis, which occurs when hair follicles become inflamed or infected, presenting as small, red, tender bumps. These infected pimples can develop when the hair follicle is irritated, such as from shaving or friction.
Ingrown hairs also create a lump when a hair curls back or grows sideways into the skin, causing an inflammatory reaction. Simple skin tags are extra flaps of soft, benign tissue that can appear in this area due to friction. They are generally harmless and asymptomatic.
Another frequent presentation is an epidermoid cyst, which forms when surface skin cells grow inward instead of shedding normally. These cysts are sacs beneath the skin filled with keratin, a soft, cheese-like protein. They are typically mobile and smooth. While usually painless, they can become inflamed or infected, leading to tenderness and swelling.
Acute Infections and Inflammatory Abscesses
Lumps that appear rapidly with significant pain, redness, and warmth often signal an acute infection or inflammatory abscess. A general skin abscess, or boil, is a painful, pus-filled lump resulting from a bacterial infection in a blocked sweat gland or hair follicle. These feel warm to the touch and require drainage by a healthcare provider.
The perineal region is susceptible to perianal abscesses, which form when a small gland lining the anal canal becomes clogged and infected. These are painful, cause swelling near the anus, and may be accompanied by systemic symptoms like fever and chills. Untreated perianal abscesses can lead to a fistula-in-ano, an abnormal tunnel connecting the anal canal to the skin.
For individuals with vulvar anatomy, a Bartholin’s cyst or abscess is a specific cause of a painful lump near the vaginal opening. This occurs when the duct of a Bartholin’s gland, which produces lubricating fluid, becomes blocked. If the trapped fluid becomes infected, it quickly develops into a tender, severely painful abscess requiring medical intervention. Pilonidal cysts, though usually found in the cleft of the buttocks, can also present near the edge of the perineum, forming a tender lump often containing hair and skin debris.
Benign Structural Growths and Masses
A lump may originate from the underlying soft tissues, often presenting as a stable, non-tender mass. Lipomas are common, arising from a collection of fatty tissue. These are typically soft, rubbery, and easily movable under the skin, growing slowly over time.
Other benign growths include fibromas, which develop from connective tissue, and hemangiomas, masses formed by an abnormal collection of blood vessels. These structural masses are generally asymptomatic. Although not cancerous, a biopsy is sometimes necessary to confirm the diagnosis and distinguish them from rarer soft-tissue tumors.
When to Seek Professional Medical Evaluation
Although most perineal lumps are benign, professional medical evaluation is necessary to establish an accurate diagnosis and rule out serious conditions. Consult a doctor for any new lump that persists for several weeks without improvement, even if it is painless. This is particularly important for lumps that are firm or fixed in place, meaning they do not move easily under the skin, as this can indicate a deeper or more concerning mass.
Immediate medical attention is warranted if the lump is accompanied by certain “red flag” symptoms that suggest an urgent issue. These include rapid growth or a sudden change in the lump’s shape, which may indicate an aggressive process. Signs of systemic infection, such as fever, chills, or general malaise, alongside a painful, red lump, suggest an abscess or deeper cellulitis that requires prompt treatment.
Any lump that causes persistent, worsening pain, or is associated with bleeding, unexplained discharge, or non-healing ulcers should be evaluated immediately. Though rare, the perineal area can be the site of malignant or precancerous conditions. Timely investigation, potentially including imaging or a tissue biopsy, is crucial for effective management.