PAMS Dermatology: Pre-Malignant and Malignant Skin Lesions Flashcards
What is a KERATOCANTHOMA?
It is a rapidly growing (1-2 weeks) Sharply demarcated, firm, central hyperkeratotic plug on sun exposed areas. It occurs typically in late life.
What are the causes of Keratocanthoma ?
Smoking, Sun exposure / trauma, HPV, genetics.
What is the Tx of keratocanthoma?
Because of similar gross and histologic features with SCC, simple
excision with 3-5 mm margins recommended for most.
What are actinic keratosis ?
These are Small, rough, scaly skin lesions with sandpaper like texture. Induration, tenderness, bleeding can be seen with potential for malignant transformation. therefore, it needs to biopsied.
What is the pathogenesis of actinic keratosis ?
Repeated sun expouser causes damage to keratinocytes with P53 oncogene mutation. This leads to dysplastic keratinosis which may lead to SCC in 20% cases.
What are the risk factors for actinic keratosis ?
*Fair skin
* Sun exposed skin (face,
extremities)
* Albinism
* Xeroderma pigmentosum
* HPV infection
What is the Tx of actinic keratosis ?
Topical:
* 5-Fluorouracil – prevents DNA replication
* Imiquimod (Aldara) – induction of alpha interferon & other cytokines
* Surgery
* Scraping
* Excision
* Other
* Cryotherapy – freeze with liquid nitrogen
* Photodynamic therapy
* Electrodessication
* Prevention
* Avoid excessive sun exposure
* Sunscreen
Moluscum contagiosum with erythematus helo indicates ?
more likely spontaneous remission.
What is Hutchinson’s sign?
It heralds herpes zozter opthalmicus.
What is the most common skin cancer ?
Basal cell carcinoma is the most common skin cancer occurs in sun exposed areas. 75% of all skin cancers. metastasis is rare unless treated. Untreted Basal cell carcinomas may metastatise to the cranial cavity.
What is the clinical presentation of basal cell carcinoma?
The basal cell carcinomas presents as lesions with rolled up borders and telangectasias in it.
What is the Tx of basal cell carcinoma ?
Surgical excision
* Moh’s micrographic surgery
What are squamous cell carcinomas ?
It is the second most common skin cancer (20% of all skin cancer). It presents as small pink erythematous scaly plaque, which may progress to ulcerated and indurated painful bleeding plaque. In many cases it is proceeded by actinic keratosis.
What is the Tx of Squamous cell carcinoma ?
Moh’s MS +/- ironising radiation +/-Topical chemotherapy (5-FU), biologics (Imiquimod), retinoids, photodynamic therapy.
What are the characteristics of high risk squamous cell carcinomas ?
*Tumour diameter >2 cm
* Breslow thickness >2 mm
* Poor differentiation
* Anatomic location (lip, ear, and temple)
* Perineural invasion
* Invasion beyond the subcutaneous fat
