CPD 89: MELANOMA Continuing Professional Development
CPD 60 Second Summary Malignant melanoma is the fifth most common invasive cancer nationally, with rising incidence. The main risk factor for its development is ultraviolet radiation exposure, especially intense and intermittent exposures and sun burn in fair-skinned individuals. Most cases of melanoma affect middle-aged individuals, though a significant proportion affect young adults. Males over 50 tend to present with thicker tumours, often on the trunk, and have a worse prognosis than females. Most melanomas occur de novo, with approximately 30% arising within a pre-existing mole. Early detection and prompt excision of melanoma remains the most important element of management, with rapidaccess pigmented lesions set up nationally for this purpose. Early stages of melanoma have excellent prognosis. Historically, the prognosis for advanced and metastatic melanoma was very poor, though dramatic improvements in the landscape of melanoma treatment have been made in the last decade with the advent of a variety of systemic therapies for advanced and metastatic disease. These include targeted therapies such as BRAF and MEK inhibitors for BRAF-mutated melanoma, and immunotherapy agents in the form of immune checkpoint inhibitors and programmed cell-death protein 1 (PD-1) inhibitors. Primary prevention strategies and public health messaging emphasise the importance of adequately protecting skin from the sun and selfsurveillance for early detection of suspicious lesions.
31
AUTHOR: Dr Emma Porter. Dermatology Registrar, University Hospital Limerick
1. REFLECT - Before reading this module, consider the following: Will this clinical area be relevant to my practice?
knowledge gap - will this article satisfy those needs - or will more reading be required?
2. IDENTIFY - If the answer is no, I may still be interested in the area but the article may not contribute towards my continuing professional development (CPD). If the answer is yes, I should identify any knowledge gaps in the clinical area.
4. EVALUATE - Did this article meet my learning needs - and how has my practise changed as a result?Have I identified further learning needs?
3. PLAN - If I have identified a
5. WHAT NEXT - At this time you may like to record your learning for future use or assessment. Follow the
4 previous steps, log and record your findings. Published by HPN. Copies can be downloaded from www.irishpharmacytraining.ie Disclaimer: All material published is copyright, no part of this can be used in any other publication without permission of the publishers and author.
Malignant Melanoma of the Skin Introduction Malignant melanoma is the fifth most common invasive cancer in Ireland, with approximately 20 cases per 100,000 per year - one of the highest incidence rates globally - and rising incidence.1 Ultraviolet (UV) radiation exposure is the main risk factor for development of melanoma, particularly intense and intermittent exposures in fair-skinned individuals.2,3 Sun bed exposure is widely recognised to increased risk of melanoma, particularly when used in younger age groups.4 Further risk factors include multiple melanocytic naevi, dysplastic naevus syndrome, a family history of melanoma, and immunosuppression. Familial genetic mutations with high penetrance are rare, with CDKN2A most frequently reported in these cases. In genome-wide association studies, single nucleotide polymorphisms in multiple genes related to nevogenesis and pigmentation have been associated with melanoma, including melanocortin 1 receptor, the gene which underlies red hair and freckles.5 Median age at diagnosis was 64 years for melanoma between 2011 and 2015 in Ireland. Melanoma patients, particularly females,
tend to have a younger age profile than those with non-melanoma skin cancers, with almost 31% of all female patients and 20% of males diagnosed before age 50. Paediatric melanoma is rare.6 Males over 50 tend to present with thicker tumours, often on the trunk, and have worse prognosis. Epidemiological studies suggest that women with melanoma have a better prognosis, regardless of whether pre or postmenopausal and when adjustments for tumour characteristics are taken into account.7,8 The majority of melanomas occur de novo, with 30% arising within a pre-existing naevus. There is emerging evidence suggesting differing characteristics of these melanomas, with naevusassociated melanoma associated with lower depth of invasion and similarities in body sites.9 Histopathological subtypes of melanoma include superficial spreading, the most common, representing a radial growth phase, and nodular (vertical growth phase). Other types include acral (hands and feet), spitzoid and desmoplastic (spindle cells). In-situ melanoma is considered pre-cancerous, non-invasive and is limited to the epidermis, without evidence of dermal invasion on histology. Lentigo maligna is
a subset of melanoma in situ with histological evidence of photodamage, typically seen on sun-exposed areas such as the face in elderly individuals. Diagnosis When diagnosed and treated early, melanoma has an excellent prognosis. Stage 1A carries a 5-year survival rate of 99%. Diagnostic and therapeutic advances contribute to further improvement in survival in all stages, though advanced melanoma still carries a poor prognosis and one fifth of patients are at stage III or IV at the time of diagnosis.1 The National Cancer Control Programme (NCCP) has developed the National Melanoma GP Referral Guidelines (Figure 1) for assessment and referral of suspicious lesions via a standardised pathway to a dermatologist or plastic surgeon, the National Pigmented Lesion GP Referral form.10,11 There are 14 rapid access centres nationally to where referrals can be sent. Standardised referral forms support inclusion of relevant clinical data for pigmented lesions including the ‘ABCDE’ system of lesion abnormalities (see Figure 1) and environmental and genetic risk factors.
