Keratosis seborrheic is a common benign skin growth whose number increases with age. They develop gradually, usually after the age of 30. Although they can occur on non-sun-exposed body parts, it is believed that the sun is significant triggering factor.
They most often develop on the trunk, back of hands, forearms, face and scalp as brownish flat growths. They can increase in size over time, their surface can become rough and of dark brown colour, so they can be very similar to moles.
The diagnosis is made based on clinical and dermoscopic examination by a dermatologist. If it can not be safely distinguished from melanoma or squamous cell carcinoma, it is necessary to remove it surgically and perform a histopathological examination.
Treatment of seborrheic keratosis
Since these are harmless lesions, no special treatment is necessary. They can be removed only for aesthetic reasons.
Their removal can be performed with radiofrequency, liquid nitrogen (cryotherapy), curettage or laser (Erbium:YAG).
Patients often complain of itching in the area where keratosis is located, as a result of which they want to remove it. Radiofrequency removal leaves no scaring. If the lesion is greater than 5mm, a lighter skin colour will remain after its removal.
Actinic keratosis is a lesion that occurs on the skin due to prolonged sun exposure, which is why they are most often present on photo-exposed body parts. They are more pronounced in people whose profession requires frequent sun exposure, like farmers, athletes, people working in the open air, as well as in people with lighter skin colour.
Keratosis Actinica is considered a precancerous lesion, because over time it can turn into squamous cell skin cancer. That is why a dermatologist should perform a preventive examination of skin lesions at least once a year.
What does actinic keratosis look like?
On the sun exposed body parts — face, extensor surfaces of hands and back of hands, round or oval, well defined reddish lesions are observed, usually at skin level. The surface is rough, with thicker or thinner scales. Sometimes small wounds can be present that are hard to heal.
Actinic cheilitis is the name for actinic keratosis found on the lips, most often on the lower one. In the early stages, redness and swelling with scales are observed. Later, as lesions progress, thicker scales, scabs, abrasions or cracks of the skin of the lips occur. These lesions have a higher risk for turning into squamous cell carcinoma, so regular checkups by a dermatologist are very important.
How is the diagnosis made?
The diagnosis of actinic keratosis can be made with quite high accuracy during dermoscopic examination. Sometimes it is advised to do a biopsy (a cutout of the lesion is taken) and a histopathological examination, to distinguish whether it is actinic keratosis or squamous cell skin cancer.
Treatment of actinic keratosis:
Good results are achieved with radiofrequency and lasers. Initial lesions can be treated with liquid nitrogen, so-called cryotherapy, with topical retionids (tretinoin, adapalene) or 5-fluorouracil. In case of large lesions, surgical removal and pathohistological examination are recommended. It is especially important to protect the skin from UV radiation with adequate clothing and preparations.