Principles and Practice of Radiation Therapy Chapter 40 Skin Cancers and Melanoma Copyright © 2010 by Mosby, Inc., an affiliate of Elsevier Inc.

Integumentary System Overview Hypodermis Dermis Epidermis Accessory structures Effects of aging

Overview Largest organ Functions 22 square feet 10 to 12 pounds Protection Temperature control Waste removal Sensory Vitamin D production

Hypodermis Subcutaneous tissue or superficial fascia Acts as the foundation Composition Adipose tissue Function Padding Insulation Shape

Dermis Reticular layer Tension lines Papillary layer

Epidermis Cellular composition Desquamation Keratinization Keratinocytes Melanocytes Langerhans cells Desquamation Keratinization

Epidermis Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale

Accessory Structures Hair Muscles Types Structure Arrector pili Lanugo Vellus Terminal Structure Shaft Root Muscles Arrector pili

Accessory Structures Glands Sebaceous Sweat Ceruminous

Accessory Structures Nails Purpose Structure Protection Manipulation Scratching Structure Root Body Matrix

Effects of Aging Reduced blood flow Thinner skin Loosened structure Decreased activity of glands Decrease in melanin

Skin Cancer Epidemiology Etiology Clinical presentation Detection and diagnosis Disease classification Pattern of spread Treatment Side effect management

Skin Cancer Types Melanoma Nonmelanoma Benign skin conditions Basal cell carcinoma Squamous cell carcinoma Merkel cell carcinoma Benign skin conditions Actinic keratosis Squamous cell carcinoma in situ

Nonmelanoma Epidemiology Incidence 13 million new cases each year 80% basal cell carcinoma (BCC) 20% squamous cell carcinoma (SCC) Deaths 1000 to 2000 deaths

Nonmelanoma Etiology Sun exposure Genetics Radiation Chemical agents Ultraviolet B (UVB) Artificially produced ultraviolet A (UVA) Genetics Hair color Complexion Xeroderma pigmentosum Radiation Chemical agents Viruses Human papillomavirus (HPV) Chronic irritations

Nonmelanoma Clinical Presentation Asymmetry Border Color Diameter Elevation

Nonmelanoma Detection and Diagnosis Screening Clinical examination Self-examination Inspect face Check hands including nails Women should examine under breasts Use two mirrors to inspect back Check legs and feet

Nonmelanoma Disease Classification Staging BCC often not staged Pathologic staging Tumor Node Metastasis (TNM) Clinical staging

Nonmelanoma Pattern of Spread Slow growing Direct extension Embryologic fusion planes Perineural space Nodes and metastases

Nonmelanoma Treatment Surgery Curettage and electrodesiccation Scraping and burning Mohs’ microscopic surgery Cryosurgery Temperature −50° Celsius Recommended for bleeding or oozing skin cancers

Nonmelanoma Treatment Laser surgery Typically performed by a dermatologist Chemotherapy Topical 5-fluorouracil (5-FU) Systemic Salvage Investigative methods Immunotherapy Photodynamic therapy

Nonmelanoma Treatment Radiation therapy treatment Treatment volume localization Visualization Palpation Treatment margins

Nonmelanoma Treatment Radiation therapy treatment Simulation Patient positioning Immobilization devices Treatment parameters Blocking Beam arrangement Special considerations

Nonmelanoma Treatment Radiation therapy treatment Treatment delivery Beam energy Superficial Electrons Photons Brachytherapy

Nonmelanoma Treatment Radiation therapy treatment Treatment delivery Dose schedule BCC Smaller than 2 cm – 4500 cGy 2 to 5 cm – 5000 cGy Larger than 5 cm – 6000 cGy SCC Smaller than 2 cm – 5000 cGy 2 to 5 cm – 5500 cGy Larger than 5 cm – 6500 cGy Lesions larger than 8 cm or with bone invasion – 6500 to 7500 cGy

Nonmelanoma Side Effect Management Acute Types of injuries Management Avoid trauma Cleansing Ointments Chronic Telangiectasis Hyperpigmentation Hair loss Necrosis

Melanoma Epidemiology Incidence is on the rise 54,200 new cases in 2003 62,190 new cases in 2006 Only 3% of all skin cancers Most deadly skin cancer

Melanoma Etiology Sun exposure Moles Genetics Family history UVB Artificially produced UVA Moles Genetics Hair color Complexion Family history Immune suppression Age Gender Xeroderma pigmentosum History of melanomas

Melanoma Clinical Presentation Types Superficial spreading melanoma Lentigo maligna Acral lentiginous melanoma Nodular melanoma

Melanoma Detection and Diagnosis Screening Physical examination Imaging studies

Melanoma Pattern of Spread Rapid vertical growth typical Risk of nodal or metastatic involvement increases with increased tumor depth

Melanoma Disease Classification American Joint Committee on Cancer (AJCC) − TNM Clark’s Breslow measurement

Melanoma Treatment Surgery Chemotherapy Radiation therapy Simple excision Reexcision Mohs’ surgery Amputation Chemotherapy Radiation therapy Dose schedule Hypofractionation

Melanoma Survival Survival by stage Stage 0 Stage I Stage II Stage III Stage IV