Week 3 - B - B.C.C/S.C.C (Actinic keratosis, Bowen's, viral), Benign - Seborrhoeic keratoses, Dermatofibroma, Cyst, Skin tag Flashcards
What is the most common and second most common skin cancers? Which cells do they arise from? Which type of skin cancer has the highest mortality rate?
Both arise from keratinocytes
* Basal cell carcinomas are the most common skin cancer (roughly 75%)
* Squamous cell carcinomas are the second most common skin cancer (roughly 20%)
Malignant melanomas make up a smaller percentage of skin cancers (less than 10%) however account for the majority of mortality rates from skin cancers (roughly 75%)
State which skin cancer type risk is increased based on the exposure * Chronic/long term sun exposure eg outdoors worker * Intense intermittent sun exposure * Excess sun exposure eg Sun burning * Artifical UV rays - sunbeds
Chronic/long term sun exposure eg outdoors workers - squamous cell carcinoma risk increased
Intense intermittent sun exposure / sun burning - melanoma and basal cell carcinoma
Artifical UV rays - SCC, BCC, MM
What is the most common skin cancer seen in immunosuppressed or transplant patients and why?
Squamous cell carcinomas are the most common skin cancer seen in immunosuppressed and transplant patients due to the increasing incidence of HPV in these grups
We are going to discuss basal skin carcinomas, squamous cell carcinomas and the precursor lesions to these cancer types At the end of this set we will also discuss common benign skin lesions What is the typical presentation of a basal cell carcinoma? describe the appearance? Is there pain?
BCC are slow growing skin-lesions often present for around 6 months before reported
They tend to repeatedly crust and scab with the patients complaining they just wont heal.
May itch or bleed.
Clinical features include a raised, rolled pearly edge, central ulceration and telangiectasia
Usually painless
What are the different risk factors for basal cell carcinoma? How does this cancer spread?
Basal cell carcinoma risk factors
Intense intermittent sun exposure (holidays) / sun burning
Artifical UV rays (sunbeds)
Where do basal cell carcinomas arise? How do they spread? What is the central ulceration seen in basal cell carcinomas known as?
Basal cell carcinomas arise from the basal cell layer of the epidermis
They are locally invasive invading the dermis but almost never metastasize
Central ulceration means BCC are often referred to as a rodent ulcer - given this name because if left untreated, they will eventually gnaw away at the skin
What are the three main subtypes of basal cell carcinoma?
Superficial basal cell carcinoma - superficial scaly plaque
Nodular basal cell carcinoma
Infiltrative basal cell carcinoma (morphoeic)
What is standard management for basal cell carcinomas? Surgical and non-surgical options exist and are based largely on the clinical features When would you use surgery - what type of surgery? When would you use non-surgical?
Surgery is usually given for nodular BCC and infiltrative BCC - the surgery is known as Moh’s surgery
Non-surgical management such as imiquimod, photodynamic therapy or cryotherapy can be used in superficial BCC (small biopsy taken to confirm diagnosis then creams given)
How is Moh’s surgery carried out?
Mohs surgery is a precise surgical technique used to treat skin cancer.
During Mohs surgery, thin layers of cancer-containing skin are progressively removed and examined until only cancer-free tissue remains. - performed under local anaethetic
What is the mechanism of action of imiquimod? What are side effects of the cream?
Imiquimod is an immunomodulator - this provokes a host immune response (induces interferon alpha) against the lesion causing a marked inflammatory reaction
SE - itch, burning, erythema
Occasionally patients will fail to report the BCC causing for a neglected BCC to form - usually very big How are these treated?
Radiotherapy is the management of choice in neglected BCC
We now move on to squamous cell carcinoma spectrum What are the precursor lesions to squamous cell carcinoma? What is SCC also known as?
Precursor lesions
* Actinic (solar) keratosis is due to dysplastic keratinocytes
* Bowen’s disease is full thickness (full epidermal thickness) or carcinoma in situ
* There are also viral lesions especially on anogenital skin that are precursors
Squamous cell carcinoma is invasive squamous carcinoma
Describe the presentation and appearance of actinic keratosis?
Actinic keraotis
Yellow/white Scaly erythematous papule/crusts on a sun-exposed site - an indicator of significant sun damage
esp scalp, face, hands
What is the management options for actinic (solar keratosis)? When is excision indicated?
Cryotherapy often used if single lesion 1st line for several lesions or field change
- topical 5-flourouracil (imiquimod second line) (if extensive damage over large areas - known as field change)
Excision is indicated in actinic keratosis for ulcerated lesions as this is highly suspicious of SCC
How does 5-fluorouracil work?
5-fluorouracil - topical cytotoxic which produces a marked inflammatory reaction at the site of application
What is Bowen’s disease? How does it present and where?
Bowen’s disease a squamous cell carcinoma in situ (not invaded the dermis)
It typically presents as an erythematous scaly plaque wit an irregular border on the lower legs of older ladies
Viral precursors to squamous cell carcinoma often present on anogenital areas What virus is linked to the majoriy of cases of anogenital viral precuorsers? What is the bowenoid type dysplasia that is seen on the glans of the penis known as?
HPV (often type 16) is associated with bowenoid dysplasia
Erythroplasia of Queyrat (EQ) (Bowen’s disease of the penis) is an in situ squamous cell carcinoma of the penis.
The glans and prepuce are most commonly involved - almost exclusively in uncircumcised penis.
SQUAMOUS CELL CARCINOMA (invasive squamous cell carcinoma) What is the presentation of these lesions? What is the appearance of the squamous cell carcinoma? Where do they arise?
Sqaumous cell carcinomas grow faster than BCC with patients usually presenting within 2-3 months and may be painful/bleeding
It presents as a hyperkeratotoic (crusted) lump or ulcer arising on sun damaged skin (ears, dorsum ofhand, bald scalp)
Often other actinic keratoses surround the areas
What are different risk factors for squamous cell carcinoma? What are the high risk sites? why are they high risk?
Different risk factors include
Chronic sun exposure - eg outdoors worker
Artifical UV rays - sunbeds
Chronic inflammatory sites eg leg ulcers
High risk sites include ears, lips and mucous membranes - high risk for metastases
Describe the appearance of seborrhoeic keratoses? Who is affected? Where do they appear?
Seborrhoeic warts are very common lesions especially in the elderly - may cause itch
They have a typical stuck on appearance with well defined edges and warty appearance - typically they are brown/black in colour
They usually are common on the face and trunk (back and chest)
What is a dermatofibroma? How do dermatofibromas typically present?
A dermatofibroma is a benign common overgrowth of the fibrous tissue of the dermis
It typically presents on the limbs as firm lumps with some pigmentation and generally fairly static and asymptomatic (can have itch)
What is an epidermoid cyst commonly known as? What can occur when squeezed or inflamed?
Epidermoid cysts are commonly known as sebaceous cyst
Firm well defined swellings which may release cheesy material if inflamed or squeezed
What is acrochordon better known as? What is the treatment?
Acrochordon better known as skin tags
Generally no treatment is required
Can use cryotherapy or excise if wanted
A 29 year old man presents with a firm slightly pigmented raised lesion of the right shin, present for 6 months and not changing. It is occasionally itchy but otherwise asymptomatic. He is generally well with no previous skin problems. What is this?
Dermatofibroma
