Topical chemotherapy is applied with a cream such as Efudex (5-fluorouracil), Carac (5-fluorouracil), or Aldara (imiquimod). It is a highly effective treatment for pre-cancerous lesions such as Actinic Keratoses (AK). As an alternative treatment to surgery, topical chemotherapy can treat some superficial Basal Cell carcinomas (BCCa) and superficial Squamous Cell carcinomas (SCCa). This treatment is best reserved for early superficial skin cancers and can be unpredictable.
5-fluorouracil creams (Efudex and Carac) are the real chemotherapeutic drugs, killing abnormal cells directly. Imiquimod (Aldara) works differently by summoning forth immune cells that do the killing. It is called an immune response modifier. Imiquimod has also been applied to other skin cancers such as Bowen's carcinoma in-situ and melanoma in-situ.
Topical Chemotherapy: is it an option?
An appointment with your physician will help to determine the answer to this question. Not all forms of skin cancer can be treated with the use of topical chemotherapy. The treatment is done by the patient at home while the doctor carefully monitors the skin response during office visits. The physician can increase or decrease the frequency of use in order to achieve the result or to limit the skin reaction. Skin reaction may range from none to severe.
The length of treatment can range from 2 to 12 weeks for actinic keratoses (AK) and 6-12 weeks for skin cancers.
Although covered by insurance, Aldara purchased directly can be expensive - $600. 5-fluorouracil on the other hand is available in generic form and costs around $100.
Topical Chemotherapy for Actinic Keratosis
Actinic Keratoses are precancerous lesions. Click here to read more about Actinic Keratoses. Typical treatment instructions would be to apply the cream, covering the entire affected area 2 nights per week 4 days apart for 16 weeks. For example, if you were to apply the cream on Monday and Thursday or Tuesday and Friday. This treatment plan is for areas no larger than 5cm by 5cm.
Topical Chemotherapy for Superficial Basal Cell Carcinoma
A superficial BCCa that does not extend deeper into lower layers of the skin can be treated with topical chemotherapy. Click here to read more about Basal Cell carcinoma. Covering the skin cancer plus one centimeter of skin surrounding the tumor, ointment will typically be applied 5 consecutive nights per week (Monday through Friday) for up to 6 weeks with imiquimod. With 5-fluorouracil application can be twice daily, every day for 6-12 weeks.
Side Effects of Topical Chemotherapy
Normal reaction of the treated area may include:
- Small, open sores
Some patients may find they need to stop treatment early or take a break in the middle of the treatment course to limit the skin reaction. In some cases especially where larger areas are treated, patients may develop flu-like symptoms that resolve quickly as treatment stops. Severe reaction can involve extensive oozing, crusting, and even ulcerations. Prolonged redness for many weeks after completing treatment can be unsightly but always resolves.
How Effective is Topical Chemotherapy?
Topical chemotherapy response can be unpredicatable, especially with imiquimod. In some cases no response would occur - no skin reaction and no cancer eradication. Even with skin reaction, cure is not guaranteed. Careful follow-up with the physician and occasionally biopsies are needed after completion of topical chemotherapy. Overall, for properly selected skin cancers, the cure rate can be 80-90%.