Psoriasis and Skin Cancer Edward Pritchard

Long Cases You could get these! Last year’s finals! - Patient with recurrent SCC, with no symptoms. History focussing on skin exposure and social. Was asked about risk factors, macroscopic and microscopic appearance of different types of skin cancer and different treatments

Skin Examination Scalp Auricles Face Extremities (upper) Chest (front and back) Abdomen (front and back) Genitalia Extremities If lesions – consider local lymph nodes etc.

Psoriasis

Definition Relapsing and remitting chronic skin condition characterised by scaly plaques Or inflammation of the dermis, with epidermal hyperproliferation

Epidemiology ~2% of the population Peak incidence in early 20s and 50s Precipitated by infection, drugs (antimalarials, B-blockers, lithium), sunlight, stress, scars, burns

Pathophysiology Immune mediated leads to increased speed of skin turnover (28 days to 4), causes thickening of the epidermis.

Symptoms and Signs Typically well demarcated red, scaly, symmetrical, non itchy plaques 5 main presentations

Plaque – typically on extensor surfaces and scalp

Guttate – small eruptions over trunk – typically 2 weeks post B streptococcal throat infection

Pustular – widespread sterile pustules

Flexural – affects flexural aspects Flexual Psoriasis – occurs typically in later life, forms in the groins, natal cleft and submammary area

Erythrodermic – extreme form affecting 90%+ of body – can be fatal Erythrodermic Psoriasis erythrodermic psoriasis may develop as the result of slow or rapid progression of existing disease, or less commonly, de novo plaques cover over 90% of the body surface protective function of the skin is lost and problems with thermoregulation, septicaemia, dehydration, high output cardiac failure and metabolic changes due to increased cutaneous blood flow may occur (1) erythrodermic psoriasis may be life threatening

Management Conservative – diet, weight loss, smoking cessation, exercise advice Medical Topical Emolients Vitamin D analogues Topical steroids (mild to moderate) Coal tar Salicylic acid Phototherapy UVB PUVA ( Psoralen + UVA) Systemic Immunosuppresent – Methotrexate, ciclosporin Biologics – Infliximab, Adalimumab Surgical – no real role

Skin Cancer

Aetiology/Risk Factors Squamous cell – UV light exposure (sunbathing), fair skin, radiation exposure, carcinogens, metastasise quickly Basal Cell – UV light exposure, radiation exposure, arsenic exposure, “never” metastasise – local tissue destruction Malignant melanoma – UV light exposure, metastasise rapidly

Symptoms and signs Squamous cell – rapidly enlarging lesion, ill defined (variable), pink colouration, may have ulceration, scaling, bleeding or weep Basal cell – slow growing lesion, well demarcated papule, raised rolled pearly edges with central depression Malignant melanoma – a new or changing mole.

Squamous Cell Carcinoma ~20% of cutaneous malignancies ~70% on head or neck Premalignant conditions (Bowen’s disease, actinic Keratosis) 95% cure rate with excision if localised disease. But metastasises rapidly to lymph with poor outcome

Basal Cell Carcinoma 75% of diagnoses Moh’s Surgery – removal of obvious tumour and thin layer of tissue. Frozen and stained, then examined under microscope. If there are tumour cells present a further, deeper layer is removed and the process repeated until tumour free. Gives best cosmetic outcome –smaller lesions.

Malignant Melanoma Asymmetrical Border irregularity Colour variation Diameter >6mm Evolution

Investigations Biopsy/Excisional biopsy (Breslow depth, Clark level – for melanoma) Stage – CT/PET

Tx + Prognosis Prognosis Management Conservative – reduce risk factors, smoking cessation Medical – if for chemotherapy Surgical – excision biopsy +/- lymph node resections Prognosis Basal cell – very good, fatality rare Squamous cell – poor Malignant melanoma – poorer (often metastasised at presentation)

Questions Thanks