A small, firm lump beneath the skin often causes concern, leading many to search for answers about its nature and whether it will resolve naturally. These common, non-cancerous skin growths are closed sacs lying just under the surface, typically filled with a semi-solid material. The question of whether such a lump, commonly referred to as a sebaceous cyst, can vanish on its own depends entirely on its structure and origin. Understanding what these growths are is the first step in knowing the likely outcome of the lesion.
Understanding Common Skin Cysts
The term “sebaceous cyst” is widely used by the public, but it is often a misnomer for the far more common type of growth known as an epidermoid cyst. A true sebaceous cyst is rare, originating from the oil-producing sebaceous glands, and is filled with sebum. In contrast, the vast majority of skin lumps are epidermoid cysts, which arise from the hair follicle or the implantation of surface epidermal cells beneath the skin.
The sac of an epidermoid cyst is lined with epithelial cells, which continuously shed and accumulate inside the sac. This accumulation is keratin, a thick, pasty, and often foul-smelling protein. Because the popular terminology refers to the epidermoid cyst in nearly all cases, this information focuses on the behavior of the more prevalent keratin-filled growth.
The Likelihood of Spontaneous Resolution
For a skin cyst to completely and permanently resolve, the entire epithelial sac or lining must be removed or destroyed. Since the cyst lining is composed of living cells that continue to produce and shed keratin, the sac acts like a permanent container that refills over time. Therefore, a cyst generally does not go away on its own, as the source of the contents remains intact beneath the skin.
While a cyst may temporarily shrink or flatten, this is usually because the contents have been partially reabsorbed or have drained to the surface. This reduction in size is not a permanent solution, and the cyst will almost certainly regrow. The only way to achieve definitive, lasting resolution is to surgically excise the entire capsule, ensuring no lining cells are left behind.
Signs of Infection and Complication
A previously quiet cyst can become symptomatic if it ruptures or becomes inflamed, which often happens due to trauma or attempts to squeeze the contents. When this occurs, the contents of the cyst are exposed to the surrounding dermal tissue, triggering a significant inflammatory response. An inflamed cyst will present with specific warning signs, including noticeable redness, localized swelling, and tenderness to the touch.
If the inflammation progresses to a bacterial infection, the area may become warm, and the pain will be more acute. A clear sign of infection is the drainage of purulent, thick, or foul-smelling material from the cyst’s central opening. When a cyst is actively infected, it typically requires treatment with antibiotics and sometimes incision and drainage to alleviate the pressure. Elective surgical removal is almost always postponed until the acute infection and inflammation have completely subsided, as operating on an inflamed area increases the risk of complications.
When Professional Removal is Needed
Definitive treatment for a persistent or recurrent cyst involves a procedure performed by a healthcare professional, such as a dermatologist or surgeon. The goal of this intervention is to excise the entire cyst wall, which prevents the continuous accumulation of keratin and stops the recurrence of the lump. The traditional method, known as conventional wide excision, involves an elliptical incision designed to remove the cyst intact, which ensures the lowest rate of recurrence.
However, this method leaves a longer scar, so for cosmetic reasons, especially on the face or exposed areas, minimally invasive techniques are often preferred. These include the minimal excision technique or the punch biopsy excision, where the contents are expressed through a small hole created by a punch tool or tiny incision. The deflated cyst sac is then carefully removed through the small opening, offering a smaller scar but carrying a slightly elevated, though still low, risk of the cyst returning if any portion of the lining is left behind.