FAQ

Epidermoid cysts do not resolve on their own. A sac-like structure (cyst wall) forms beneath the skin, and as long as this sac remains, its contents will continue to accumulate. The cyst tends to grow gradually over time, and surgical removal of the entire sac is necessary for a complete cure.

Please avoid squeezing an epidermoid cyst yourself. Doing so carries risks such as worsening inflammation due to bacterial infection, recurrence because the sac remains intact, spread of infection to surrounding tissue, and increased scarring. Please seek proper surgical removal at a medical facility.

The exact cause of epidermoid cysts has not been fully established, but contributing factors are thought to include blocked or clogged pores, skin invagination from trauma or acne scars, and in rare cases, human papillomavirus (HPV) infection. Some individuals may also be genetically predisposed to developing them.

An epidermoid cyst is located deeper beneath the skin than a pimple, and when touched it feels like a firm, elastic lump. A small dark opening (the punctum) is often visible at the center, and unlike a pimple, it does not resolve on its own within a few days. Pimples are closer to the skin surface, and when they contain pus, white or yellow fluid may be visible through the skin.

An epidermoid cyst is formed by keratin and sebum collecting inside a sac-like structure; it has a central opening (punctum) and may produce a distinctive odor. A lipoma is a mass of fat cells, has no opening, and produces no odor. An epidermoid cyst tends to move with the skin, whereas a lipoma tends to move freely beneath the skin.

Epidermoid cysts can develop anywhere on the body, but they occur most frequently in areas with active sebaceous activity, such as the face, neck, back, behind the ears, buttocks, and armpits. These areas are prone to clogged pores, creating conditions favorable for cyst formation.

If left untreated, an epidermoid cyst will gradually enlarge over time. If bacteria enter the cyst, it can become infected, resulting in an inflamed epidermoid cyst with redness, swelling, pain, and warmth. Once inflamed, treatment becomes more complex and scarring tends to be more noticeable. We recommend seeking treatment while the cyst is still small.

We recommend consulting a plastic surgery or dermatology specialist for the treatment of epidermoid cysts. Plastic surgery in particular excels in techniques to minimize scarring, making it especially well-suited for cysts on the face or other visible areas. Our clinic is staffed by board-certified members of the Japan Society of Plastic and Reconstructive Surgery.

A lipoma is a benign tumor that develops from the proliferation of subcutaneous fat tissue. It is soft with a rubber-like elasticity and characteristically moves freely beneath the skin. Lipomas are most commonly seen in people in their 40s to 60s, though they can develop at any age. Malignant transformation is extremely rare, and lipomas are considered fundamentally benign.

Because a lipoma is a benign tumor, watchful waiting is one option when there are no symptoms. However, lipomas tend to grow gradually over time, and surgery performed after significant growth will result in a larger scar. In addition, rare cases may require differentiation from malignant liposarcoma, so we recommend consulting a specialist at least once.

The cause of lipomas has not been clearly established. Genetic factors may be involved, and lipomas can occur in multiple family members. Trauma has been proposed as a possible trigger, though this has not been confirmed. Obesity is not considered to have a direct relationship with lipoma development.

Lipomas do not disappear on their own, and shrinking them with medication is also difficult. Surgical removal is required to treat a lipoma definitively. That said, because lipomas are benign, surgery is not always necessary in the absence of symptoms, and watchful waiting remains an option.

Lipomas can develop anywhere there is subcutaneous fat, but they occur most frequently on the back, shoulders, neck, arms, and thighs. Occasionally they may form within muscle or in internal organs. Some patients develop multiple lipomas simultaneously, a condition known as multiple lipomatosis.

An inflamed epidermoid cyst is a condition in which bacteria enter the cyst, causing infection and inflammation. The affected area becomes red and swollen, accompanied by significant pain and warmth. If left untreated, pus may accumulate and the cyst may rupture spontaneously. Treatment is more complex than for a non-inflamed cyst, so prompt attention is necessary.

If you are experiencing severe pain from an inflamed epidermoid cyst, please visit a medical facility as soon as possible. As a temporary measure, keeping the affected area clean and applying a cold pack wrapped in a towel may help reduce the pain. Over-the-counter pain relievers can also provide short-term relief, but drainage of the pus is required for definitive treatment.

Oral antibiotics alone are not sufficient to completely treat an inflamed epidermoid cyst. If pus has accumulated, incision and drainage is necessary. After drainage, either a two-stage procedure (removing the sac once inflammation has resolved) or a one-stage procedure (removing the sac while inflammation is still present) may be performed. We will recommend the most appropriate treatment approach based on your condition.

Surgery is performed under local anesthesia, so discomfort during the procedure is minimal. There may be a brief stinging sensation from the anesthetic injection, but surgery begins only after adequate anesthesia has taken effect. In some cases inflammation can reduce anesthetic efficacy, and additional anesthetic will be administered as needed. Appropriate pain medication is prescribed after surgery, so pain can be managed effectively.

If your epidermoid cyst is turning red, it is a sign that inflammation may be beginning. Please visit a medical facility as soon as possible. As inflammation progresses, swelling and pain can intensify and treatment becomes more complicated. Until you are seen, keep the affected area clean and avoid touching or squeezing the cyst.

Surgery for an epidermoid cyst is covered by National Health Insurance. For patients with a 30% co-payment, the estimated cost is approximately ¥5,000–¥14,000 for exposed areas (such as the face or hands) and approximately ¥4,000–¥13,000 for non-exposed areas (such as the back or buttocks). Costs vary depending on the size, location, and presence of inflammation. Initial consultation fees and examination costs may be charged separately.

Procedure time varies depending on the size and location of the cyst, but at our clinic it is typically completed in as little as 5 to 20 minutes. We use the punch excision method (umbilicoplasty technique), which takes less time and results in a smaller scar compared to conventional incision methods. The procedure is performed on an outpatient basis, so no hospital stay is required.

After surgery, desk work and other light-duty jobs that do not involve strenuous physical activity are generally possible on the same day. However, we recommend avoiding positions that put pressure on the treated area and refraining from vigorous exercise for approximately one to two weeks. For cysts on the back or buttocks, sitting for extended periods may be uncomfortable, so we suggest scheduling your surgery on a day that works with your routine.

Our clinic uses the punch excision method (umbilicoplasty technique), which allows for a smaller, less noticeable scar compared to conventional incision methods. Surgery is performed by a board-certified plastic surgeon with attention to cosmetic outcomes. How noticeable the scar is can vary depending on the size and location of the cyst as well as individual factors such as keloid-prone skin.

The punch excision method is a surgical technique in which the cyst opening (punctum) is used as the center point, and the entire sac is removed through a circular punch incision. Compared to the conventional fusiform (elliptical) incision, the incision line is shorter and the resulting scar tends to be less noticeable. The procedure is also faster and places less burden on the body, which is why our clinic actively employs this approach.

Yes, surgery for an epidermoid cyst is covered by National Health Insurance. An epidermoid cyst is a benign tumor and its surgical removal is recognized as medically necessary, making it eligible for insurance-covered treatment. In cases where the procedure is performed solely for cosmetic purposes, it may be classified as self-pay, but standard epidermoid cyst removal surgery is covered by insurance.

Lipoma surgery is also covered by National Health Insurance. For patients with a 30% co-payment, the estimated cost is approximately ¥5,000–¥14,000 for exposed areas and approximately ¥4,000–¥13,000 for non-exposed areas. Please note that lipomas are often larger than epidermoid cysts, and costs may be higher as a result. Please confirm the exact cost at the time of your consultation.

Same-day surgery may be possible at our clinic for first-time patients. However, depending on the condition and size of the cyst, the presence of inflammation, and availability in the surgical schedule, surgery may be scheduled for a later date. If you would like same-day surgery, please let us know when making your appointment.

IC Clinic Ueno is open from 10:00 to 19:00 (closed 14:00–15:00; last reception at 18:30). We are open on Saturdays and Sundays as well, so patients who are busy on weekdays are welcome to visit. Please note that we are closed on certain days such as year-end and New Year holidays; please call us or check our website for details.

IC Clinic Ueno is conveniently located a 1-minute walk from Ueno Station on the Tokyo Metro Hibiya and Ginza Lines, and a 3-minute walk from JR Ueno Station. Our address is 3-16-5 Higashi-Ueno, Taito-ku, Tokyo, Cinq U Building 1F. We are close to the station, making it easy to stop by on your way home from work or while out shopping.

Our clinic operates by appointment. Please make a reservation by phone at 0120-000-702 or through our website. Walk-in patients are also welcome, but please be aware that those with appointments will be seen first and you may need to wait. If you would like same-day surgery, please let us know at the time of booking.

Minors may undergo surgery at our clinic. However, a parent or legal guardian must be present at the time of surgery, or a signed consent form from a parent or legal guardian is required. For consultations and examinations only, a parent or guardian does not need to be present. The consent form is available for download on our clinic website.

IC Clinic Ueno primarily treats epidermoid cysts (atheromas), inflamed epidermoid cysts, and lipomas, as well as other plastic surgery conditions such as moles and earlobe repair. Our clinic is staffed by board-certified members of the Japan Society of Plastic and Reconstructive Surgery, and all procedures are performed on an outpatient basis.