Coups EJ. Lack of Knowledge of Type of Skin Cancer Diagnosis. Arch Dermatol. 2010;146(10):1175-1197. doi:10.1001/Arch Dermatol.2010.274
The prevalence of melanoma and nonmelanoma skin cancer (NMSC) has increased dramatically in the United States over the past 35 years. More than 750 000 individuals are living with a history of melanoma,1 and approximately 13 million have a history of NMSC.2 Discrepancies exist between estimates of melanoma prevalence based on self-reported interview data vs Surveillance, Epidemiology, and End Results (SEER) cancer surveillance data.2 These discrepancies may result from patients' lack of knowledge of the type of skin cancer diagnosed.
The current study examines the extent to which individuals who reported a skin cancer history were not able to report the type of skin cancer diagnosed. Potential demographic, health, and health care correlates of lack of knowledge of skin cancer diagnosis type are also examined.
The data were drawn from the nationally representative 2007 and 2008 US National Health Interview Surveys (NHIS). Additional information regarding the NHIS is available elsewhere.3
A total of 21 781 and 23 393 individuals were selected as sample adults for the 2007 and 2008 NHIS, respectively. Participants indicated whether they had “ever been told by a doctor or other health professional that . . . [they] had cancer or a malignancy of any kind,” and if so, the type of cancer(s) diagnosed. The sample for the current study consisted of the 1172 individuals who reported a diagnosis of melanoma, NMSC, or a skin cancer of unknown type (ie, the participant could not state whether the cancer was melanoma or NMSC).
Participants indicated their race, ethnicity, sex, current age, level of education, annual family income, overall health, and health care coverage. The number of years since skin cancer diagnosis was calculated based on reported age at skin cancer diagnosis and current age.
A dichotomous variable was created representing whether participants knew the type of their skin cancer diagnosis. A small number of individuals (n = 24) reported being diagnosed with melanoma or NMSC and also an unknown type of skin cancer. For analytic purposes, these individuals were denoted as not knowing the type of skin cancer. Using SUDAAN 10.0 (RTI International, Research Triangle Park, North Carolina) and a statistical significance cutoff of P < .05, I conducted a series of logistic regression analyses with knowledge of skin cancer diagnosis as the dichotomous outcome variable and each of the variables listed in the “Measures” subsection herein (except race and ethnicity) as independent variables. All percentages reported were weighted.
The participants were 97.3% non-Hispanic white and 49.7% female. Among the participants, 20.8% reported their skin cancer diagnosis as melanoma; 64.2% as NMSC; and 19.0% as unknown type. (Percentages sum to >100% because some individuals reported multiple types of skin cancer diagnosis.) As summarized in the Table, individuals were significantly more likely to lack knowledge of their type of skin cancer diagnosis if they had a lower level of education or family income, worse self-reported health, or no private health care coverage. Participant sex, age, and time since cancer diagnosis were not significantly associated with lack of knowledge of skin cancer diagnosis type.
Almost 1 in 5 individuals reporting a skin cancer diagnosis did not know whether it was melanoma or NMSC, and this rate was higher among certain subgroups. The greater lack of knowledge of skin cancer diagnosis type among individuals with lower education or income is of concern because these individuals have a poorer prognosis when diagnosed as having melanoma.4 Lack of knowledge of skin cancer type was not associated with elapsed time since diagnosis, suggesting that poor memory over time is not a relevant factor. Some participants who did not know whether they were diagnosed as having melanoma or NMSC may have known that they were diagnosed with basal or squamous cell carcinoma, and these terms should be added to population-based surveys such as the NHIS.2 Health care providers should also educate patients with skin cancer about their disease and verify their knowledge of the type of skin cancer diagnosed and the importance of subsequent preventive behaviors.
Correspondence: Dr Coups, The Cancer Institute of New Jersey, 195 Little Albany St, Room 5567, New Brunswick, NJ 08901 (email@example.com).
Accepted for Publication: May 18, 2010.
Financial Disclosure: None reported.
Funding/Support: Dr Coups receives support from National Cancer Institute grant 1K07CA133100.
Disclaimer: The sponsor had no role in the design and conduct of the study; in the collection, analysis, and interpretation of data; in the preparation of the manuscript; or in the review or approval of the manuscript.