Key points Ask What are dermatologists’ perceptions regarding overdiagnosis of melanocytic lesions, and is awareness of overdiagnosis associated with pathologist characteristics or interpretive behavior? Findings In this survey study of 115 dermatopathologists, two-thirds perceived overdiagnosis to be a public health problem for atypical nevi, half for melanoma in situ, and one-third for invasive melanoma. More experienced dermatologists were substantially less likely to perceive that atypical naevi and melanoma in situ are overdiagnosed; Perceptions of overdiagnosis were not significantly associated with the diagnoses given in the case studies. Meaning Dermatopathologists’ perceptions of melanoma overdiagnosis vary; Awareness of overdiagnosis may not be sufficient to reduce overdiagnosis. |
Importance
Despite evidence of overdiagnosis of in situ and invasive melanoma, practicing dermatologists’ perceptions of overdiagnosis and potential associations between perceptions of overdiagnosis and diagnostic practices have not been studied.
Aim
To examine practicing US dermatologists’ perceptions of melanoma overdiagnosis as a public health problem, and to associate dermatologists’ diagnostic behaviors with perceptions of melanoma overdiagnosis.
Design, environment and participants
This survey study included 115 board-certified and/or fellowship-trained dermatologists and their diagnostic interpretations on a set of 18 skin biopsy cases (5 sets of slides comprising 90 melanocytic skin lesions).
Participants interpreted the cases remotely using their own microscopes. Survey invitations were issued between 2018 and 2019, and data collection was completed in 2021. Data analysis was conducted from June to September 2021.
Main results and measures
Agreement versus disagreement that overdiagnosis is a public health problem for atypical nevi, melanoma in situ, and invasive melanoma. Associations between perceptions of overdiagnosis and interpretive behavior regarding case studies.
Results
Of 115 dermatopathologists , 68% (95% CI, 59%-76%) agreed that overdiagnosis is a public health problem for atypical nevi; 47% (95% CI, 38%-56%) for melanoma in situ; and 35% (95% CI, 26%-43%) for invasive melanoma.
Dermatopathologists with more years of practice were significantly less likely to perceive that atypical nevi are overdiagnosed, e.g. For example, 46% of dermatopathologists with 20 or more years of experience agreed that atypical nevi are overdiagnosed compared with 93% of dermatologists with 1 to 4 years of experience.
Compared with other dermatologists, those who agreed that all 3 conditions are overdiagnosed were slightly more likely to diagnose the study cases as mild to moderate dysplastic nevi (odds ratio, 1.26; 95% CI, 0. 97-1.64; P = .08), but the difference was not statistically significant.
Dermatopathologists who agreed that invasive melanoma is overdiagnosed did not differ significantly in the diagnosis of invasive melanoma for the study cases compared with those who disagreed (odds ratio, 1.10; 95% CI, 0 .86-1.41; P = 0.44).
Conclusions and relevance
In this survey study, approximately two-thirds of dermatologists thought that atypical naevi were overdiagnosed, half thought that melanoma in situ was overdiagnosed, and one-third thought that invasive melanoma was overdiagnosed. No statistically significant associations were found between perceptions of overdiagnosis and interpretive behavior when diagnosing skin biopsy cases.
Comments
As the most serious type of skin cancer, a melanoma diagnosis carries emotional, financial and medical consequences. That’s why recent studies finding overdiagnosis of melanoma are a major cause for concern.
“Overdiagnosis is the diagnosis of a disease that will not harm a person in their lifetime. If melanoma is overdiagnosed, it means too many people receive the frightening news that they have cancer and receive and pay for unnecessary treatment,” said Kathleen Kerr, professor of biostatistics at the UW School of Public Health.
Kerr recently published the results of a study involving more than 100 dermatologists (pathologists who specialize in skin diseases and diagnose melanoma) to find out whether they believe the overdiagnosis of melanoma is a public health problem in the US. USA and whether that belief affects your own conclusions. Pathologists were given biopsy slides to diagnose and were surveyed about their perceptions of overdiagnosis.
Kerr discussed the results of this study, published in JAMA Dermatology , in the following Q&A with UW News:
How do you know if a disease is being overdiagnosed?
Kathleen Kerr: Overdiagnosis is often studied by looking at population-level data rather than individual cases. Melanoma diagnoses have increased in the US. If there were truly a melanoma epidemic, we would expect melanoma deaths to show a corresponding increase, as there has not been a major breakthrough in treatment during this time. However, deaths from melanoma have been remarkably consistent. This suggests that the increase in melanoma diagnoses is largely due to overdiagnosis.
Why does this happen when it comes to melanoma?
Kerr: The problem is multifaceted. Most of us non-doctors think that if we have something on our skin that is possibly cancer and we get a biopsy, then the pathologist’s diagnosis after examining the skin tissue under a microscope is definitive. The reality is more complicated.
Skin abnormalities are some of the most difficult cases for pathologists to diagnose. Previous research has shown that different pathologists examining the same skin biopsy sometimes give different diagnoses, to a very surprising degree. The same pathologist examining the same case on two different occasions may even give two substantially different diagnoses.
While advanced melanoma is fairly easy for pathologists to diagnose, difficulties arise in cases where the biopsy shows some type of abnormality that does not appear to be melanoma but could be a precursor to melanoma. These are the cases in which pathologists show the greatest diagnostic variability and the cases that raise the possibility of overdiagnosis.
What did you find in your study?
Kerr: The first component of our recent article was a survey of practicing dermatologists’ perceptions of overdiagnosis. Approximately half perceive that non-invasive melanoma is overdiagnosed and one-third perceive that invasive melanoma is overdiagnosed .
Additionally, most dermatologists agree that they see cases that should not have been biopsied in the first place. This points to overdiagnosis as a system-wide problem, a problem that may be rooted in too many skin biopsies.
The second component of our study looked for relationships between pathologists’ perceptions of overdiagnosis and how they diagnosed actual skin biopsies. We thought that those who think invasive melanoma is overdiagnosed might be more reserved in making this diagnosis, but this was not true. In fact, those who think invasive melanoma is overdiagnosed were slightly more likely to diagnose invasive melanoma compared to other dermatologists who examined identical cases.
What do you think is the importance of this finding?
Kerr: Overdiagnosis is a really challenging problem because both doctors and patients are afraid of missing a cancer, which is understandable. Our study shows that there is widespread recognition of melanoma overdiagnosis among dermatologists.
We also show that awareness of overdiagnosis may not be sufficient to reduce overdiagnosis. It is not surprising that such a complicated problem has no simple solution. Reducing overdiagnosis will require patients and primary care physicians to exercise more restraint in obtaining skin biopsies, and pathologists to exercise restraint in diagnosing cases such as melanoma.
