Vol. 15 Issue 8
Sebaceous Cyst Removal
A sebaceous cyst is a small, mobile, superficial, asymptomatic dome-shaped sac containing sebum, keratin and lipid. It enlarges slowly, and it is firm to fluctuant. A sebaceous cyst has a rancid odor due to fat content, bacterial infection and decomposition.
Sebaceous cysts commonly occur where hair follicles are present – on the scalp, back, neck or face. It is often unclear whether an inflamed cyst is infected, so many providers opt to treat them with antibiotics, incision and drainage.
Multiple cysts are associated with lipomas or fibromas of the skin. When multiple cysts are present, consider the possibility of Gardner's syndrome. This syndrome is associated with premalignant polyps of the colon. Since associated cancer is rare, histologic evaluation is necessary only when solid tumors or unusual findings are present.
There are two methods for cyst removal. Method one is used when the cyst sac is identified and can be pulled easily through the incision. Method two is used when the cyst sac is not identified or pulled easily through the incision.
Contraindications to removal include a cyst on the face, presence of a bleeding disorder, diabetes, immune compromise, and current infection of the cyst.
The equipment for each method is listed in the table. After obtaining informed consent, position the patient so that the cyst is accessible. Cleanse the 3-inch area surrounding the cyst with antiseptic skin cleanser, drape the cyst with the sterile drape, and put on gloves.
Method 1 Instructions
Perform the field block by anesthetizing the perimeter around the abscess with 1% or 2% lidocaine without epinephrine. Do not inject lidocaine into the abscess because it does not work well in an acidic medium.
Using a No. 11 scalpel, incise the cyst lengthwise to allow easy extraction. With curved hemostats, pull the sac out onto the surface of the skin.
Using a No. 11 scalpel, cut the elastic tissue around the outer edges of the sac until released. Irrigate with 0.9% sodium chloride. Close the wound with sutures, and apply a pressure dressing.
Method 2 Instructions
Perform the field block as above. Using a No. 11 scalpel, incise the cyst lengthwise to allow easy extraction. Express the cyst contents, and put them into a jar containing 10% formalin. Send the specimen to the pathology laboratory. Explore the cavity with curved hemostats. Break down any sacs or septa. After expressing all purulent material, pack the wound with iodoform gauze, leaving a small amount protruding from the wound. Remove 1 or 2 inches of the iodoform gauze daily for approximately 10 to 14 days, until it is all removed. Cover the treated area with 4x4 gauze and tape.
If the cyst is on the head, do not pack the wound site with iodoform gauze. Instead, roll 4x4 gauze into a roll. Suture the incision in two places, leaving room for drainage. Leave the ends of the sutures 2 to 3 inches long. Place gauze roll on top of the incision, and tie it tightly in place with the ends of the suture to form a pressure dressing. Remove the gauze roll in 7 days.
Instruct the patient about signs of infection and to apply cool compresses if pain and swelling occur. After 24 hours, the patient should apply heat for 5 to 10 minutes four to six times per day for 2 to 3 days. To manage severe pain, prescribe one or two tablets of Tylenol No. 3 every 4 to 6 hours for 24 hours. After 24 hours, the patient should switch to plain or extra-strength acetaminophen. Schedule the patient to return to the office in 48 hours for recheck.
11400: Excision, benign lesion except skin tag, trunk, arms or legs: lesion diameter 0.5 cm or less
11401-06: Differing lesion diameters
11420: Excision, benign lesion except skin tag, scalp, neck, hands, feet, genitalia, lesion diameter 0.5 cm or less
11421-26: Differing lesion diameters
Colyar M, Ehrhardt C. Ambulatory Care Procedures for the Nurse Practitioners. 2nd ed. Philadelphia, Pa.: Philadelphia; 2004.
Pfenniger JL, Fowler G. Procedures for the Primary Care Physician. St. Louis, Mo.: Mosby; 2003.
Zuber TJ. Minimal excision technique for epidermoid (sebaceous) cysts. Am Fam Physician. 2002;65(7):1409-1412, 1417-1418, 1420.
Margaret Colyar is a family and pediatric nurse practitioner who is a member of the ADVANCE for Nurse Practitioners editorial advisory board. She practices at Naples Health Care Associates in Naples, Fla.
Equipment Needed for Sebaceous Cyst Removal
Antiseptic skin cleanser
1% to 2% lidocaine
Two syringes: 3 mL and 10 mL
27- to 30-gauge, inch needle (for anesthesia)
18-gauge, 1 1/2-inch needle (for irrigation)
No. 11 scalpel
Curved hemostats (sterile)
0.9% sodium chloride (sterile)
Iodoform gauze inch to 1-inch
Container with 10% formalin
4x4 sterile gauze