Our findings show that the overall rate of melanoma visits has increase in comparison to the baseline increase in population (). Given that the melanoma visits sampled in this study could be either initial visits or follow-up visits for a previously diagnosed melanoma, we are unable to comment on melanoma incidence from these data. However, other studies indicate that the incidence of melanoma has been on the rise over the past several decades [5
], which would help explain why the number of visits has significantly increased. The increase in number of visits also suggests that management in the ambulatory care setting has accommodated the rising number of melanoma patients. There are a few explanations for this trend. Partly contributing to the increasing melanoma incidence are better detection practices and earlier detection of melanoma [9
], which both occur most often in the ambulatory care setting. It has also been shown that the rise in incidence is mainly attributable to thin melanomas, while the number of intermediate or thick melanomas has remained stable [10
]. Recent data show that dermatologists are diagnosing more melanomas and are doing so at earlier stages than any other specialty [12
]. They are now managing cases previously referred to surgical specialties. With dermatologists increasingly handling more diagnosis responsibilities, these factors could easily contribute to the observed increase in number of visits in the ambulatory care setting. It would be important to discern whether ambulatory care visits by these patients are the most efficient way to manage their disease. Efficiency in this context could be described as the least number of patient visits necessary in the appropriate management of a given melanoma.
Our study also reveals that the age of patients with melanoma visits increasing at approximately twice the rate of the population age increase (). The mean age of patients with melanoma visits was about 45 years in 1979 and about 60 years in 2010. This suggests that the age at which people are diagnosed with melanoma is advancing over time. An analysis of the crude and birth-cohort adjusted age-specific rates of melanoma suggests that rates will continue to increase as earlier cohorts age [14
]. However, it seems likely that this trend is due to more than just an aging population; otherwise the mean age of melanoma visits would track more closely with the mean age of the population. A reasonable explanation could include the changing solar exposure practices over the past decades and the long latency to the development of melanoma. If preventative practices were being appropriately employed, we would expect to see fewer young people developing melanoma, thereby contributing to the higher age at diagnosis. In recent years, however, adolescents and young adults have been reported to be at increased risk of skin cancer due to suboptimal sunscreen use, high rates of sunburning, and tanning bed use [15
]. Time will tell if these practices will lead to a higher incidence of melanoma in the younger populations. Further concerning evidence is that in US females, melanoma is reported to be the most common cancer in the 25 to 29 age group, and the second most common cancer in women aged 30 to 34 years [16
]. As mentioned previously, better detection practices over the years could also explain an older age at diagnosis given the long latency period of the disease, especially if a diagnosis was missed at an earlier age.
During the time period examined by our study, the proportion of melanoma visits by women appears to closely correlate with the proportion of females in the population (). However, albeit small, there is still a decline in the proportion of melanoma visits by females. This contrasts the fairly constant proportion of females in the population. In a study of melanoma incidence and mortality in US whites from 1969 to 1999, Geller et al. demonstrated increased melanoma incidence in men and women (aged 20 to 65 years or older), with greater increases noted in the older male population [17
]. Other studies support these findings [18
]. With evidence demonstrating a greater incidence in males, we would expect to see a greater proportion of male melanoma visits. Possibly explaining this trend is that men may be less likely to visit a physician or maintain compliance with follow-up visits. Studies have demonstrated that while women have higher medical care service utilization and are more likely to use outpatient medical services, men are less likely to have physician office visits or preventative care visits [20
]. Further, men are presenting to the physician with thicker melanomas than women, possibly necessitating in-patient treatment, which is not accounted for by the NAMCS data [23
]. Women living longer and having lower melanoma mortality can also influence this trend. While men and women aged 20 to 44 had a melanoma mortality decrease of 29% and 39%, respectively, men 65 years and older had a 157% mortality increase [17
]. This was a 3-fold greater increase than for women of the same age.
In an effort to contain healthcare expenditures, greater emphasis has been placed on primary care physicians (PCPs) providing healthcare, as specialists, including dermatologists, are assumed to be more costly. In terms of management of skin conditions, this positions PCPs in a difficult situation, as much of their practice involves management of chronic conditions like hypertension and diabetes mellitus, and relatively little time diagnosing and treating skin disease. Fleischer Jr. et al. found that some of the most common cutaneous diagnoses made by family physicians were diagnosed at least 10 times more frequently by dermatologists [12
]. Smith et al. demonstrated the large disparity in experience between dermatologists and other physicians with outpatient management of skin cancer [24
]. The authors found that the majority of skin cancer visits (81%) were managed by dermatologists, with the remaining visits being managed by nondermatologists. Consistent with this, our data shows that over a few decades, dermatologists received more melanoma visits, while melanoma visits to family and internal medicine physicians have significantly decreased over this time period (Figures –). Given that the majority of melanoma visits have been going to dermatologists, nondermatologists may have relatively little clinical exposure to melanoma. Studies show that most PCPs referred patients presenting with suspicious appearing pigmented lesions to a dermatologist, as many PCPs did not feel confident in their ability to recognize melanoma and thought their training was not adequate to prepare them to diagnose and manage pigmented lesions [25
]. In surveys of US medical students and residents, the majority reported little to no training in skin care examinations and felt a lack of competency and confidence in performing these [27
]. With a declining proportion of melanoma visits going to PCPs, this lack of confidence may only worsen. Conversely, for dermatologists, the increase in melanoma clinical experience has likely led to an increased level of confidence and expertise in melanoma management. The effect of greater physician experience on improved quality of care and medical cost reduction has been demonstrated [30
The rise in melanoma visits to dermatologists over the past three decades has also corresponded with a decline in visits to surgeons (), a finding that is also reflected in other studies. In a study looking at the surgical management of melanoma by dermatologists and surgeons, the percentage of the total patients treated by dermatologists rose from 18% in 1979–84 to 57% in 1991–97, while those treated by general surgeons decreased from 58% to 15% and from 23% to 13% for plastic surgeons over the same period [32
]. Many factors could contribute to this trend, including public recognition of dermatologists as skin care experts, and dermatology residencies providing more surgical and procedural training than in the past, allowing graduates to offer more comprehensive skin care than before [33
As NAMCS data is derived from office-based physician practices in USA, one of the limitations of this study is the lack of data from hospital inpatient and military medical facilities. In the case of advanced melanomas managed by the general or plastic surgeons, this could underestimate both the overall total number of melanoma visits and the number of melanoma visits seen by these providers. With the NAMCS database limited to physicians primarily involved in outpatient care outside the federal system, this could lead to potential selection bias or sampling error. Another limitation of this study is that the melanoma visits could represent either new diagnosis or followups on previously diagnosed melanoma. To better estimate the new cases of melanoma, perhaps visits associated with excisions would provide a more accurate assessment. Lastly, the NAMCS data reflect the ability of the various practitioners to make an accurate diagnosis. For those with less experience in dealing with pigmented lesions, misdiagnosis could occur. For example, it is not uncommon for a seborrheic keratosis to masquerade as melanoma, which could lead to an overestimation of melanoma visits. Likewise, if a practitioner is using a particular system for diagnosis, such as the Asymmetry, Borders, Color, and Diameter (ABCD) system, they potentially could misdiagnose a melanoma that did not fit this system. This could lead to either an underestimation or overestimation of melanoma visits.