Actinic keratosis

From EyeWiki



Actinic keratosis
Classification and external resources
ICD-10 [1]57.0


Actinic keratosis is a premalignant squamous lesion. It appears clinically as a erythematous, scaly macule or papule. The lesion typically presents in middle aged or elderly patients. Sun exposed areas are most commonly affected. Squamous cell carcinoma may develop from preexisting actinic keratosis. Thus, biosy of suspected lesions and long term follow-up are necessary in patients with this condition. The risk of subsequent metastastatic dissemination is very low (0.5-3.0%)[1]

Disease Entity

Actinic Keratosis ICD-9-CM 702.0

Actinic Keratosis ICD-10-CM L57.0

Disease

Actinic keratosis is a premalignant squamous lesion. It appears clinically as a erythematous, scaly macule or papule. The lesion typically presents in middle aged or elderly patients. Sun exposed areas are most commonly affected. Squamous cell carcinoma may develop from preexisting actinic keratosis. Thus, biosy of suspected lesions and long term follow-up are necessary in patients with this condition. The risk of subsequent metastastatic dissemination is very low (0.5-3.0%)[2]

Etiology

The most likely factor that leads to the development of actinic keratosis is sunlight exposure, specifically UVA and UVB sunlight.[3] Exposure to these forms of radiation leads to a complex series of genetic events which eventually lead to the development of actinic keratosis and squamous cell carcinoma.

Risk Factors

History of chronic sunlight exposure. Lack of sunscreen use when outdoors. Fairer skin types

General Pathology

Histologically, hyperkeratosis, parakeratosis, dyskeratosis, and solar elastosis are seen. Cellular atypia may be present, with increased nuclear-to-cytoplasmic ratio, pleomorphism, or nuclear hyperchromatism.

Pathophysiology

Exposure to these forms of radiation leads to a complex series of genetic events which eventually lead to the the proliferation of squamous epithelial cells and dysplastic changes in the skin that are characteristic of actinic keratosis.

Primary prevention

Frequent sunscreen use and avoidance of overexposure to sunlight.

Diagnosis

Preliminary diagnosis may be made based on clinical appearance. However, definitive diagnosis requires a biopsy with review by a pathologist.

Actinic keratosis 1.7 x PAS.jpg
Actinic keratosis 7.0 x PAS.jpg

History

Patients will usually present with a slowly developing scaling and erythomatous lesion of the skin.

Physical examination

Actinic Keratosis of the lower eyelid. (c) 2014 one.aao.org

Examination of skin can be performed with a slit-lamp, dermatoscope, or with the naked eye.

Signs

Erythematous (red), scaly macule (flat pigmented lesion) or papule (solid, elevated lesion) may be present on the skin surface. Multiple lesions may be present.

Symptoms

The skin of affected areas may feel rough, or have a "sandpapery" texture. The lesions may have a round and scaly appearance. Itching or irritation may be present on the skin of affected individuals.

Clinical diagnosis

It appears clinically as a erythematous, scaly macule or papule. It is most commonly found on the face, lips, ears, back of the hands, forearms, scalp or neck.[4]

Diagnostic procedures

Examination of skin can be performed with a slit-lamp, dermatoscope, or with the naked eye. After a suspicious lesion has been identified, it should be biopsied and examined by a pathologist to confirm the diagnosis.

Laboratory test

Histopathology may be performed on skin biopsies.

Differential diagnosis

Basal cell carcinoma, squamous cell carcinoma, lentigo maligna.

Management

Observation, medical, or surgical treatment may be recommended depending on individual circumstances.

General treatment

The most common treatment is biopsy of the lesion with observation or medical treatment, since this is a benign condition.

Medical therapy

Topical medications, cryotherapy, and photodynamic therapy (PDT) have been described as treatment for actinic keratosis. Photodynamic therapy using 5-aminolevulinate (ALA) is based on topical application of ALA to a skin lesion and subsequent illumination of the lesion with red light, and has been shown to be an attractive alternative to cryotherapy with improved asthetic outcomes.[5]

Medical follow up

Medical follow up is indicated by individual practitioners depending on the circumstances of the individual.

Surgery

Lesions may be completely excised if there is concern for malignancy. However, in most cases, actinic keratosis may be observed clinically for progression. Laser treatments may also be an option if there is no concern for malignancy.

Surgical follow up

Surgical follow up will be indicated by individual surgeons. Actinic keratosis generally has a low chance of progressing to more malignant lesions.

Complications

Medical treatments have various possible complications and side effects, and should be discussed with your physician before starting treatment. Surgical treatments may also have complications, such as wound infection or dehisence, and should be discussed with your surgeon before undergoing surgery. Observation also carries with it the possibility that actinic keratosis will develop into a more malignant lesion.

Prognosis

Actinic keratosis has a generally good prognosis. It rarely progresses into squamous cell carcinoma or other malignancy.

Additional Resources

References

  1. Ophthalmic Pathology and Intraocular Tumors, Section 4. Basic and Clinical Science Course. San Francisco: American Academy of Ophthalmology; 20011-12
  2. Ophthalmic Pathology and Intraocular Tumors, Section 4. Basic and Clinical Science Course. San Francisco: American Academy of Ophthalmology; 20011-12
  3. Ortonne, J.-P. (2002), From actinic keratosis to squamous cell carcinoma. British Journal of Dermatology, 146: 20–23. doi: 10.1046/j.1365-2133.146.s61.6.x
  4. http://www.mayoclinic.org/diseases-conditions/actinic-keratosis/basics/definition/con-20030382
  5. R.M. Szeimiesa, S. Karrera, S. Radakovic-Fijanb, A. Tanewb, P.G. Calzavara-Pintonc, C. Zanec, A. Sidoroffd, M. Hempele, J. Ulrichf, T. Proebstleg, H. Mefferth, M. Mulderi, D. Salomonj, H.C. Dittmark, J.W. Bauerl, K. Kernlandm, L. Braathenm, Photodynamic therapy using topical methyl 5-aminolevulinate compared with cryotherapy for actinic keratosis: A prospective, randomized study, Journal of the American Academy of Dermatology, Volume 47, Issue 2, August 2002, Pages 258-262, ISSN 0190-9622, http://dx.doi.org/10.1067/mjd.2002.119649.