Cryotherapy, also known as cryosurgery, is a commonly used in-office procedure for the treatment of a variety of benign and malignant skin lesions.
The mechanism of destruction in cryotherapy is necrosis, which results from the freezing and thawing of cells. Treated areas re-epithelialize. Adverse effects of cryotherapy are usually minor and short-lived.
By 1990, 87% of dermatologists used cryotherapy in their practice. The general advantages of cryotherapy are its ease of use, its low cost, and its good cosmetic results. Most skin cancers are treated with excision or other destructive procedures, such as electrodesiccation and curettage. Superficial basal cell skin cancers and Bowen disease can be treated with cryotherapy.
Recurrence rates for primary basal cell carcinoma vary with treatment modality. The 5-year recurrence rate for cryotherapy may be as low as 7.5% if lesions are chosen judiciously. This percentage compares favorably with published recurrence rates following other procedures.
Published rates include surgical excision, 10.1%; curettage and electrodesiccation, 7.7%; radiation therapy, 8.7%; and all non-Mohs modalities, 8.7%. Well-circumscribed tumors are most suitable for cryotherapy. The indolent local growth of these well-circumscribed tumors accounts for the high cure rates quoted in the literature.
Cryosurgery (Liquid Nitrogen) Treatment & Post Procedure Care
What is Cryosurgery?
Cryosurgery is a technique for removing skin lesions that primarily involves the surface of the skin, such as warts, seborrheic keratosis, skin tags or actinic keratosis.
It is a quick method of removing the lesion with minimal scarring. The liquid nitrogen needs to be applied long enough to freeze the affected skin. By freezing the skin, a blister is created underneath the lesion. Ideally, as the new skin forms underneath the blister, the abnormal skin on the roof of the blister peels off. Occasionally, if the lesion is very thick (such as a large wart), only the surface is blistered off. The base or residual lesion may need to be frozen at another visit. It takes about one to three weeks for the scab to fall off, which is when the new layer of skin has formed under the blister. Areas of thinner skin, such as the face, may heal a little faster.
What to Expect Over the Next Few Weeks:
During Treatment – Area being treated will sting, burn, and then possibly itch.
Immediately After Treatment – Area will be red, sore, and swollen.
Next Day – Blister will form and tenderness starts to subside.
Apply a Band-Aid if necessary.
7 Days – Surface is dark red/brown and scab-like.
Apply Vaseline® or an antibacterial ointment, such as Polysporin®,
2 to 4 Weeks – The surface starts to peel off. This may be encouraged gently during bathing, when the scab is softened. Do not pick.
No makeup should be applied until area is fully healed.
The goal of cryosurgery is to achieve a blister. Most patients will have a blister forming following the treatment, which can be a bit painful. But sometimes, the blister is so thin that it can’t be seen and may have minimal swelling. Occasionally, a blood blister forms that can be quite dramatic but is harmless.
Rarely, the blister may become infected. When this happens, the blister becomes unusually tender, the fluid becomes cloudy, and the redness around it becomes more extensive (and may even form streaks). If this happens, contact our office.
Some lesions, especially those on the face, may leave a slight pale discoloration.
True scarring, involving the deeper layers of the skin, is unlikely.
How to Take Care of the Skin after Cryosurgery
A Band-Aid can be used for larger blisters or blisters in areas that are more likely to be traumatized, such as the fingers and toes. If the area becomes dry or crusted, an ointment (Vaseline®, Bacitracin®, or Polysporin®) can be applied.
Cleanse the area gently with a mild soap cleanser (i.e. Dove) and cool water
Pat the area dry with a lint-free cloth and apply an ointment
(Vaseline®, Bacitracin®, or Polysporin®).
Avoid glycolic acids, Vitamin C, scrubs, and creams for 7 to 10 days.
If approved by your Provider, you may bathe, swim, exercise, and otherwise follow all of your normal activities.
The area may get wet while bathing, but swimming or hot tub use should be avoided for one week following a treatment or while the skin is open.
In general, anaesthesia is unnecessary. Although, for very small children, we will sometimes suggest applying a topical anaesthetic cream at home before the office visit.
The most common adverse effects are pain, swelling/blistering, potential for infection, and possible pale discoloration of the skin after it heals.