Basal Cell Cancer. Treatment.
Treatment
Electrodesiccation and curettage.
This treatment is most beneficial for nodular BCCs less than 6 mm in diameter, regardless of anatomic site; selected larger BCCs, depending on their anatomic site; and superficial BCCs. It is not appropriate for morpheaform BCCs because margins cannot be clinically defined. Lesions on the nose and nasolabial folds may be treated if they are well defined and very small; otherwise these high-risk areas should be treated by Mohs’ micrographic surgery. However, the treatment is particularly useful for ear lesions, where mobilization of skin for closure after excision is difficult.
Curettage requires firm dermis on all sides and below the tumor to enable the curette to distinguish between dermis and soft tumor. If the tumor encroaches on the fat, the curette cannot distinguish between fat and soft tumor, and an alternate procedure must be used. Curettage should be avoided for lesions on the back and shoulders, where the dermis is thick, unless the BCCs are superficial and small. Proper technique requires vigorous curettage, usually two to three times; therefore, lesions on the eyelid or lip area are treated by other methods. It is especially useful for lower extremity tumors, where tissue mobilization for excision may be difficult. Wounds created by electrosurgery ooze serum and accumulate crust during a 2- to 6-week healing period.
Excision surgery.
Excision surgery is preferred for large tumors with well-defined borders on the cheeks, forehead, trunk, and legs. The cosmetic result is good and healing time is less than that required for electrosurgery. Excision with primary closure is technically difficult on the ears and nose. The advantage of feeling the tumor with a curette is lost and adequate margins must be taken. A 98% cure rate was achieved in one study when BCCs less than 2 cm were excised with excisional margins of 4 mm around the tumor. One large series revealed 5-year recurrence rates of BCCs excised from various anatomic sites: 0.7% on the neck, trunk, and extremities; 3.2% on the head if lesions were less than 6 mm in diameter; 5.2% on the head if lesions were 6 to 9 mm in diameter; and 9.0% on the head if lesions were 10 mm or more in diameter.
INCOMPLETELY RESECTED BCC.
Adequate excision, peripherally and in depth, is the key to surgical control, and the demonstration of tumor cells at the margins of excision is associated with recurrence rates of more than 30%. Data support the policy of immediate re-excision for all patients with incompletely excised basal cell carcinomas rather than a “wait-and-see” policy after incomplete excision. Re-excision may not be necessary if the patient’s life span is limited or if treatment of a possible recurrence would not be difficult.
Cryosurgery.
Cryosurgery with liquid nitrogen delivered with a spray apparatus or a cryoprobe is appropriate for small-to-large BCCs of the nodular and superficial types with clearly definable margins (laterally and in depth). It is not indicated for tumors deeper than 3 mm unless thermocouples are used to measure depth of freeze. A biopsy is performed as a separate operation before the cryosurgical procedure to determine cell type and extent of the tumor or just before the cryosurgery if there is no doubt about the diagnosis. Postoperative pain is moderate to severe. The appearance of a wound a few days after treatment is sometimes alarming to patients.
Mohs’ micrographic surgery.
Mohs’ surgery is a microscopically controlled technique that may be used for all types and sizes of BCCs. The procedure is unnecessarily destructive for smaller lesions or for lesions with well-defined clinical margins, such as nodular or superficial multicentric BCCs.
Mohs’ surgery is the treatment of choice for most sclerosing BCCs and other BCCs with poorly defined clinical margins; for tumors in areas of potentially high recurrence, such as the nose or eyelid; for very large primary tumors; and for large recurrent BCCs