Dermatology Flashcards
Name 3 types of skin cancer.
- BCC (75%) - in situ, grows slowly.
- SCC (20%) - can metastasise, grows rapidly.
- Melanoma (5%).
What is Keratoacanthoma?
A benign variant of SCC that arises in a hair follicle. It is unlikely to metastasise.
Presents as a dome shaped keratin plug
What is Bowen’s disease?
Bowen’s disease is also known as SCC in situ. It is characterised by red and scaly patches.mainly on lower leg
What is the treatment for bowens disease
Cautery
Cryotherapy
5-Fluouracil
Photodynamic phototherapy
What is Acitinic keratoses
Irregular crusty yellow white warty lesions on sun exposed areas that are premalignant
What is the treatment for actinic keratoses
Cautery
Cryotherapy
5-Fluouracil
Photodynamic phototherapy
Where is melanoma commonly found in men and women
Men = back and chest Women = Lower legs
Give 5 early signs of melanoma.
MAJOR 1. Enlargement. 2. Colour change (almost always darkening). MINOR 3. Irregular shape. 4. Bleeding. 5. Itching.
What is the ABCDE of melanoma?
Asymmetrical. Border irregularity. Colour variability. Diameter >5mm. Elevation irregularity.
Give 4 risk factors for melanoma.
- High density freckles.
- Red hair.
- > 100 moles.
- > 5 atypical moles.
- Family history.
- Sunlight - intense exposure in early years
- Increasing age
Give 4 differential diagnoses for melanoma.
- Melanocytic neavi.
- Seborrhoeic wart.
- Freckle.
- BCC.
- Pyogenic granuloma.
Give 3 factors that can be used to determine the prognosis of melanoma?
- Breslow’s thickness - the thinner (<1mm) the better.
- Younger = better prognosis.
- Female = better prognosis.
Describe the progression from melanocytic naevi (mole) to nodular melanoma.
Melanocytic naevi -> dysplastic melanocytic naevi -> in situ melanoma -> superficial spreading melanoma -> nodular melanoma.
What is the main cause of all skin cancer?
SUN EXPOSURE - UV light.
What is the treatment for malignant melanoma?
Surgical excision.
Lymphadenectomy
Adjuvant chemotherapy
Describe the characteristics of squamous cell carcinoma
Locally invasive malignant tumour of squamal keratinocytes that produce ulcerated lesions with hard, raised, everted edges
W
where is squamous cell carcinoma usually found
in sun exposed areas including the scalp, face, ears and lower leg
Describe the characteristics of basal cell carcinoma
Commonest malignant tumour
Tumour of the basal keratinocytes that produces pearly nodules with a rolled telangiectatic edge which may ulcerate
Where might basal cell carcinomas be found
Typically on the face in sun exposed areas
Describe the progression of SCC
solar/actinic keratosis to Bowens to SCC
Describe the treatment of SCC
Excision and radiotherapy to affected nods
Describe the treatment of BCC
Excision or cryo/radio for superficial BCC’s
What is psoriasis?
Chronic inflammation in the dermis driven by T cells (Th1 and Th17) and cytokines leading to hyperproliferation of keratinocytes and abnormally rapid growth of the epidermis
Describe the epidemiology of psoriasis
Peaks in 20s and 50s
Sex F=M
Genetics = 30% have a FH
Describe the pathology of psoriasis
Type IV hypersensitivity reaction to unidentified antigen leading to epidermal proliferation due to Th1 cell cytokine up regulation
What are the triggers for psoriasis
- Group A streptococcal infection.
- Lithium.
- UV light.
- Alcohol.
- Stress.
- Drugs (Li, Beta blockers, anti-malarials, ACEi and NSAIDs)
What are the signs of psoriasis
Symmetrical well defined red plaques with silvery scale
Nail pitting and onycholysis
Some develop seronegative arthritis
Where is psoriasis commonly found
On extensors (elbow, knees, trunk, palms and soles
On flexures, axiallae, groins,
Scalp, behind ears, navel an d sacrum
What are the 3 variants of psoriasis
Guttate
Pustular
Erythroderma and generalised pustular
Describe guttate psoriasis
Drop like salmon pink papule in a fine scale mainly on the trunk, upper arms and legs
In which individuals is guttate psoriasis most common
Occurs in children and young adults and is associated with streptococcus pharyngitis
Describe pustular psoriasis
Sterile pustules triggered by steroid withdrawal, drugs (li), topical psoriasis localised to the palms and soles
Describe the treatment for psoriasis.
- Emollients and reassurance.
- Vitamin D and A analogues e.g. calcipotriol and tazarotene and steroids (Betmethasone or hydrocortisone) topical therapy
- Phototherapy
- Non biologicals
- Biologicals
Describe the UV phototherapy treatment for psoriasis
Use Psoralen which is a photosensitising agent followed by UVB
Describe the non-biological treatment for psoriasis
Methotrexate - inhibit folic acid metabolism and DNA replication = anti proliferative and anti inflammatory
Ciclosporin
Acretretin (Oral retinoid)
What are the biological treatments for psoriasis
Anti-TNF
- Infliximab
- Etanercept
- Adalimumab
What are emollients used for?
They hydrate the skin and reduce itching.
What receptors do glucocorticoids target?
Cytoplasmic receptors.