Surgery for Other Benign Lesions of the Vulva

Inclusion Cyst

An epidermal inclusion cyst is another name for a sebaceous cyst. These cysts are common wherever hair and sebaceous glands are present ( Fig. 76.1 ). They create a swelling and may be painful to the touch. If they become secondarily infected, they will be associated with cellulitis and may form an actual abscess. The cysts form as a result of blockage of the duct exiting the skin surface from the underlying sebaceous gland or hair follicle. When the duct is obstructed, the fatty secretion of the gland and shed-off squamous cells distend the duct and create the cyst ( Fig. 76.2 ).

FIG. 76.1, Three sebaceous cysts are seen in the hair-bearing area (right labium majus) of the vulva. These common cysts can be simply excised by making an elliptical incision at the base of the cyst and wedging the incision into the subcutaneous tissue. The wound is closed with two or three interrupted 3-0 Vicryl sutures.

FIG. 76.2, This large cyst was painful and rapidly increasing in size. The differential diagnosis included a cyst of the canal of Nuck with herniated intestine or fat, as well as a large sebaceous (inclusion) cyst.

Initial treatment for an inclusion cyst is the application of hot, wet compresses to the lesion to liquefy the secretion and drain the obstructed duct, with subsequent elimination of the cyst. For recurrent, persistent, or enlarging cysts, the treatment is surgical excision.

For cysts 1 cm or smaller, an elliptical incision is made in the skin encompassing the cyst. The incision is carried deeply to circumscribe the cyst and is wedged inward to meet below the cyst. The entire section, including skin, subcutaneous tissue, cyst wall, and contents, is removed en masse.

Cysts larger than 1 cm are removed by making a straight-line incision over the mass to the level of the cyst wall beneath the epithelium ( Fig. 76.3 ). The edge of the skin is elevated with Adson-Brown forceps, and the skin margins are dissected away from the cyst wall with Stevens tenotomy scissors. The margins of the skin flaps are then held with Allis clamps for traction, and the cyst wall is completely circumscribed by sharp dissection with the Stevens scissors ( Fig. 76.4 ). The cyst wall should not be grabbed with clamps because this will result in rupture, leakage of contents, and difficulty in extracting the entire cyst ( Fig. 76.5 ). When the entire cyst is freed, it is removed. Excess skin is trimmed, and the wound is closed in layers with 3-0 Vicryl ( Fig. 76.6 ).

FIG. 76.3, An incision is made directly over the mass and extended to just superior to the mass and the lower pole of the labium majus.

FIG. 76.4, With Stevens scissors, the mass is separated from the skin margins and flaps are developed. Allis clamps are applied to the skin margins of the flap for traction. The base of the cyst is separated from the connective tissue. The latter is clamped with tonsil clamps for hemostasis.

FIG. 76.5, The cyst is completely excised. From the leaking foul-smelling material, it is identified grossly as a sebaceous cyst. The cyst is placed in fixative and sent to the pathology laboratory.

FIG. 76.6, The wound is closed in layers with interrupted 3-0 Vicryl sutures.

Hidradenoma

This usually benign sweat gland tumor creates a smooth, elevated, firm nodularity on the vulvar skin surface ( Fig. 76.7 ). It looks like a firm sebaceous cyst. The tumor is small (i.e., <1 cm). The lesion should be excised by circumscribing an ellipse of skin with a margin of 2 to 3 mm around the mass and extending the incision deeper into the subcutaneous tissue. The skin and tumor are grasped with an Allis clamp, and traction is applied with the use of Stevens scissors. The deep subcutaneous fat is dissected free from the base of the tumor, and the entire small mass of tissue containing the lesion is removed. Histopathologically, the appearance of the tumor under the low-power lens of the microscope is ominous because of the glandular complexity ( Fig. 76.8 ). However, higher-power lens inspection reveals the cells and nuclei to be clearly benign ( Fig. 76.9 ).