Aldara (Imiquimod)

Aldara (imiquimod) is a topical cream with many uses in dermatology.
It works by activating the body’s immune system to get rid of pre-cancerous, cancerous, and virally-infected cells.

Aldara does not destroy these cells by itself. It focuses the immune cells of the body to locate and destroy the undesirable cells. Cancer cells survive by escaping normal body surveillance mechanisms. Aldara allows some of these mechanisms to be restored, stimulates the production of interferon (an important immune mediator), and pushes surveillance cells to attack pre-cancerous, cancerous, and virally-infected cells.

If this sounds like a wonder drug, it most certainly is. Aldara has changed many aspects of dermatology practice. Besides being an effective anti-wart treatment, it allows treatment of some skin cancers (basal and squamous cell carcinomas) without surgery.

Aldara is supplied in tiny plastic packets which are intended for single use. I do not recommend throwing the packet out if it wasn’t used completely. This medication is usually supplied in small quantities, but costs a lot of money. If one packet can last for several days, use it! I have not seen any clinical decrease of efficacy when packets are used for more than one day.

Warts:
Aldara is currently approved for treatment of genital warts, but not warts on other parts of the body. This does not mean that it only works for warts on the genitals. In fact, I have been using Aldara to treat warts everywhere on the body and find it very effective. Warts on genital skin are covered with a very thin epidermis (top layer of the skin). That allows for Aldara’s easy penetration into the skin. Warts on other skin surfaces (feet, hands, fingers, etc) are often covered with thick epidermis. Hence, Aldara does not penetrate into the skin and has no chance to work. But the way around it lies in trying to thin the epidermis down with salicylic acid, tazarotene cream, or by filing. Once the top layer of the skin is no longer thick, Aldara penetrates the skin and works quite nicely. The time for warts to go away differs from patient to patient. One person may use Aldara for a week and his or her warts melt right away. Another person may have to apply the cream for many months.

Actinic keratoses:
These pre-cancerous lesions respond very well to Aldara. The treatment is usually accompanied by some redness, scaling, or crusting. If you have an important event coming up, it may be reasonable to postpone Aldara use until after the big day. The approved way of treating actinic keratoses is twice weekly for 16 weeks. I usually do not stick to this regimen. It is simply too long for most patients. I usually see patients every two weeks and increase the Aldara dose until significant inflammatory response is seen. That reduces the treatment duration to approximately 4 or 6 weeks.

Basal cell carcinoma:
Aldara is approved for treatment of superficial basal cell carcinomas (BCCs). In this type of BCC, cancerous cells are located close to the top layer of the skin. The cure rate for Aldara use in superficial BCCs is reported to be around 80%. I use Aldara in superficial and small nodular (deeper) BCCs. Since an 80% cure rate leaves 20% of cancer recurrence, this treatment has been modified to increase the cure rate. I usually start Aldra treatment (5 times per week for 6 weeks) after curettage (scraping) of BCCs. As a rule, the BCC site becomes very irritated and crusted as the treatment progresses. No pain is observed. After 6 weeks Aldara is discontinued, and the treatment site is left to heal. The recurrence rate is minimal. Cosmetic results after this therapy are usually quite good.

Squamous cell carcinoma:
Aldara is not approved by the FDA for treatment of squamous cell carcinoma (SCC). Yet, in my practice, just like in many other dermatology practices, Aldara became a routine treatment for small and superficial SCCs. Just like for BCCs, I prescribe Aldara for SCCs after the initial curettage of the tumor. Results of the treatment are similar for BCCs and small SCCs.

It is clear that the treatment with Aldara is not for every BCC and SCC. Large or deeply invasive tumors should not be treated with this modality. The final decision of whether this treatment is appropriate for a particular tumor needs to be made in consultation with your dermatologist.

Melanoma in-situ:
Surgical excision still remains the standard of care in treatment for all types of melanoma. Multiple reports of Aldara use for superficial melanoma (in-situ, or limited to the top layer of the skin) have been published in professional dermatology literature. It does appear that Aldara is effective for this type of melanoma. If surgical excision is an option, it should be a preferred method of treatment for melanoma. If the patient is too frail to withstand surgery, if melanoma in-situ covers very large areas on the face, or if surgery will destroy important facial structures (eyelids, lips), Aldara treatment may be attempted. No guidelines for Aldara use in melanoma have been established. The goal of the treatment will be to elicit an inflammatory response to destroy the tumor.>

Links: www.aldara.com

Alexander Doctoroff, D.O., F.A.O.C.D.
Assistant Chief of Dermatology
Veterans Administration Medical Center, East Orange, New Jersey
Clinical Assistant Professor of Medicine
University of Medicine and Dentistry of New Jersey
www.metropolitanderm.com