A 51-year-old woman noticed a rapidly growing black lesion on the upper arm (Figure 179-1) and presented to her doctor. A narrow-margin biopsy confirmed an 8-mm-thick nodular melanoma. She was referred to surgical oncology for sentinel lymph-node biopsy, and one node was positive. She underwent a course of chemotherapy, and though she remains disease-free 2 years later, she is carefully monitored for metastasis and new primary lesions by a multidisciplinary team including family medicine, dermatology, and medical and surgical oncology.
An 8 mm thick nodular melanoma on the arm of a middle-aged woman. (Reproduced with permission from Richard P. Usatine, MD.)
A 60-year-old man underwent a skin exam as part of his regular physical exam. His family doctor noticed an irregular brown black patch on the back (Figure 179-2) and performed a narrow-margin scoop shave, which was diagnostic for melanoma in situ. The patient underwent wide local excision in the office with 5-mm margins and follows up regularly for skin exams with a cure rate very near 100%.
A melanoma in situ on the back. With appropriate margins, the cure rate after excision approaches 100%. (Reproduced with permission from Richard P. Usatine, MD.)
Melanoma is the third most common skin cancer and the most deadly. The incidence of melanoma and the mortality from it are rising. Most lesions are found by clinicians on routine examination. When discovered early, surgical treatment is almost always curative. However, as depth increases, so does the risk of metastasis and mortality. New chemotherapy regimens are more promising than ever, but the best prognosis comes with prevention and early detection.
In 2018, the American Cancer Society estimates that 91,270 people in the United States will be diagnosed with melanoma, and 9320 will die from it.1
Melanoma incidence has increased in every age group and in every thickness over the course of 1992 to 2006 among non-Hispanic whites, with death rates increasing in those older than age 65 years.2
Incidence continues to increase worldwide at approximately 4% to 8% per year.3
In the United States, the death rate for melanoma is decreasing among persons younger than age 65 years.2
Deaths from thin melanomas account for more than 30% of total deaths.
The lifetime risk of developing melanoma is 2.6%.1
Risk factors can be broadly thought of as genetic risks, environmental risks, and phenotypic risks arising from a combination of genetic and environmental risks. For example, a fair-skinned child (genetic) who gets a sunburn (environmental) is much more likely to develop freckles (phenotypic) and ...