Actinic (Solar) Keratosis, Squamous Cell Carcinoma and Basal Cell Carcinoma

Diagnosis/Definition

• AK (ICD-9: 702.0): Rough, scaled, pink macules or thin papules often more easily perceived by palpation than visual inspection, found on chronically sun-damaged surfaces of the face, scalp, ears, hands and forearms that may be associated with sensations of pruritus, burning, or hyperesthesia.
• SCC (ICD-9 depends on location; 173.X): Similar to AK, usually thicker or larger.
• BCC (ICD-9 depends on location; 173.X): May be similar to AK when of superficial multifocal type; nodular BCC is common and is a telangiectatic or pearly papule or nodule that may have surface erosion.

Initial Diagnosis and Management

• Persons with fair skin, especially those who sunburn easily and tan poorly, as well as those with occupations or hobbies resulting in excessive and long-term sun exposure are at increased risk.
• Actinic keratoses can generally be diagnosed clinically, but biopsy may be indicated to verify diagnosis or exclude non-melanoma skin cancer (basal cell carcinoma, etc.) if refractory to conventional therapy. Actinic Keratoses have the potential (from 1-10%) to develop into squamous cell carcinomas and should therefore be treated when observed.

• Cryotherapy – freezing with liquid nitrogen causes blistering and shedding of the damaged skin.
• Curettage – curettage is the removal of a lesion by scraping it with a sharp instrument.
• Topical 5-Fluorouracil – most useful when there are many keratoses, especially on the face. The cream is applied once or twice daily for 2-4 weeks.
• Topical Retinoids – may be effective for the treatment of some actinic keratoses.
• Imiquimod Cream – a new immune response modifier showing promising results.
• Excisional Biopsy – definitive treatment and useful when lesions are suspicious for squamous cell carcinomas.
• Photodynamic Therapy – a new technique in which a photosensitizer is applied to the affected area prior to exposing it to a strong source of visible light. This is currently not available at MAMC and likely does not offer an advantage to topical fluorouracil.
• Laser Surgery – this modality is most appropriate for the treatment of extensive actinic keratosis of the lips (actinic cheilitis). This is currently not available at MAMC.
  Chemical Peels – alternative way to treat patients with extensive, actinically-damaged skin. This is not currently available at MAMC.

Ongoing Management and Objectives

• Long-term patient follow-up may be necessary because of the real possibility of development of new actinic keratoses or non-melanoma skin cancer.
• Frequency of follow-up is dependent on the individual clinical situation (i.e., every 4 – 12 months).
• Prevention and education are vital to patient care. Monthly self-examination is recommended. Sun avoidance, protective clothing, sunscreen protection may prevent future actinic skin damage.

Indications for Specialty Care Referral

Large or numerous actinic keratoses resistant to available therapy.

Biopsy-proven BCC or SCC whose treatment is outside the scope of practice of the primary care provider.

Criteria for Return to Primary Care

Actinic keratoses have resolved and/or a suitable treatment plan has been established.