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Article Excerpt
OBJECTIVES
This continuing nursing educational (CNE) activity is designed for nurses and other health care providers who care for and educate patients and their families about skin cancer in skin of color. For those wishing to obtain contact hour credit, an evaluation follows. After studying the information presented in this article, the nurse will be able to:
1. Discuss the incidence of skin cancer in skin of color.
2. Identify the features of basal and squamous cell cancers in skin of color.
3. Describe the occurrence of melanoma in skin of color.
4. Define the characteristics of cutaneous T-cell lymphoma and Kaposi sarcoma in skin of color.
Skin cancer is the most common malignancy in the United States and represents approximately 35% to 45% of all neoplasms in Caucasians (Ridky, 2007), 4% to 5% in Hispanics, 2% to 40% in Asians, and 1% to 20% in Blacks (Gloster & Neal, 2006; Halder & Bridgeman-Shah, 1995). The incidence of skin cancer has been increasing among Caucasians (Ridky, 2007), but remains relatively low in people of color. Data have been limited for non-White populations, making accurate determination of incidence and mortality difficult.
The low incidence of skin cancers in darker-skinned groups is primarily a result of photo-protection provided by increased epidermal melanin, which filters twice as much ultraviolet (UV) radiation as does that in the epidermis of Caucasians (Montagna & Carlisle, 1991). The larger, more melanized melanosomes of darker-skinned groups absorb and scatter more energy than do the smaller melanosomes of Caucasians (Brenner & Hearing, 2008). Hence, UV radiation, the most important predisposing factor for skin cancer in Caucasians, plays a lesser role in people of color.
When skin cancer occurs in people of color, patients often present with an advanced stage, and thus, worse prognosis in comparison to Caucasian patients (Cormier et al., 2006; Hu, Sora-Vento, Parker, & Kirsner, 2006). Furthermore, certain types of skin cancer, such as dermatofibrosarcoma protuberans, predominate in people of color (Halder & Bridgeman-Shah, 1995). The anatomic distribution may or may not be different from that seen in Caucasians, depending on the specific type of skin cancer. Treatment is generally the same among all racial groups.
Predictions estimate that by the year 2050, Hispanics, Asians, and Blacks will represent approximately 50% of the U.S. population (Gloster & Neal, 2006; U.S. Census Bureau, Population Division, 2000). Hence, given the often atypical clinical presentation, the difficulty in detecting certain features such as color variegation in dark skin, and pigmentation of some skin cancers that are usually not pigmented in Caucasians, a high degree of suspicion must be maintained by physicians and other health care providers when examining skin lesions in people of color (Halder & Bridgeman-Shah, 1995). In this review, the differences in risk factors, clinical presentation, and mortality associated with skin cancers in Blacks, Asians, and Hispanics compared to Cancasians will be discussed. Forms of skin cancers that can present atypically in skin of color will be included and consist of basal cell cancer, squamous cell cancer, melanoma, cutaneous T-cell lymphoma, Kaposi sarcoma, and dermatofibrosarcoma protuberans.
Basal Cell Cancer
Basal cell cancer (BCC) is the most common type of skin cancer in Caucasians, Hispanics, and Asians (Rubin, Chen, & Ratner, 2005) (see Table 1). Hispanics are six times more likely to be diagnosed with BCC than squamous cell cancer (SCC) and are more likely to be diagnosed with multiple BCCs compared to a solitary SCC (Byrd-Miles, Toombs, & Peck, 2007). In contrast, BCC represents the second most common skin cancer in Blacks (Gloster & Neal, 2006; Halder & Bridgeman-Shah, 1995). The majority of BCCs in a clinical series at Howard University in Washington, DC, from 1960-1986 occurred in light-complexioned, as opposed to darker, Blacks (Halder & Bang, 1988). Thus, the frequency of BCC appears to be directly correlated with the degree of pigmentation in the skin, being most common in fair Caucasians and least common in African blacks.
UVR exposure is the most common etiologic factor for BCC in all racial groups (Gallagher et al., 1995) (see Table 1). Other possible risk factors for BCC include scars (Mora & Burris, 1981), ulcers (Abreo & Sanusi, 1991), chronic infections, immunosuppression (Maloney, Comber, Cordon, & Murphy, 2006), previous radiation treatment (Walther, Grossman, & Troy, 1981), and both physical and thermal trauma (Ewing, 1971; Gloster & Neal, 2006). Genetic disorders, such as albinism (Asquo, Agweye, Ugare, & Ebughe, 2007), xeroderma pigmentosum (Giannotti, Vanzi, Difonzo, & Pimpinelli, 2003), and nevoid BCC syndrome (Kimonis et al., 1997) are also risk factors for BCC.
The clinical features of BCC are similar in Blacks, Asians, Hispanics, and Caucasians. Most patients with BCC are elderly and present with asymptomatic, translucent, solitary nodules with central ulceration (Rubin et al., 2005) (see Table 1). Telangiectasias and a pearly, rolled border in dark skin or in a pigmented tumor may be difficult to discern. Interestingly, when BCC does occur in skin of color, pigmentation is present in more than 500% of the tumors (Bigler, Feldman, Hall, & Padilla, 1996; Gloster & Neal, 2006) (see Table 1). In contrast, only 50% of BCCs in Caucasians are pigmented. When pigmented BCC presents in skin of color, there are often incorrect diagnoses, such as seborrheic keratoses, malignant melanoma, or nevus sebaceous (Halder & Bridgeman-Shah, 1995). BCCs in Asians have been reported...
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