Traditionally, melanoma age curves by histologic type vary; coding of histologic site has not been consistent. However, histologic sites tend to correspond to the body site of the melanoma. Superficial spreading melanoma, common on the upper back or the female leg, occurs in the fourth and fifth decades of life.1,2 Nodular melanoma, common on the trunk, is usually reported in the fifth or sixth decade of life.1,2 Lentigo maligna melanoma occurs most often on the head and is most commonly diagnosed in the seventh decade of life.1,2 Superficial spreading melanoma accounts for about 70% of melanomas, whereas nodular and lentigo maligna melanomas account for 10% to 15% and 5% of melanomas, respectively.2 Overall, melanomas of the trunk, arms, and legs are generally superficial spreading melanomas and some nodular melanomas, while melanomas of the head are lentigo maligna melanomas. In an attempt to understand how types of melanoma vary with age, the crude and birth-cohort adjusted melanoma incidence rates were examined by body site.
Dennis LK. Melanoma Incidence by Body Site: Effects of Birth-Cohort Adjustment. Arch Dermatol. 1999;135(12):1553-1554. doi:10-1001/pubs.Arch Dermatol.-ISSN-0003-987x-135-12-dlt1299