Dysplastic Nevi
http://www.100md.com
《新英格兰医药杂志》
To the Editor: Naeyaert and Brochez (Dec. 4 issue)1 highlight the old published National Institutes of Health (NIH) guidelines for the management of dysplastic nevi but do not mention that since 1992 the NIH has recommended the elimination of the term.2 Indeed, the condition is not precisely defined by clinical morphology, dermatoscopy, or molecular biology. The NIH now considers dysplastic nevi to be one form of benign acquired melanocytic nevi and, by some analyses, the most common nevi found on humans.3,4 Of note, nuclear atypia is not a separate criterion for dysplastic nevi but rather can be seen with any melanocytic nevi. Dysplastic nevi should be considered benign lesions and treated accordingly, with repeated excisions reserved only for those showing clinically significant cytologic atypia.5
The term "dysplasia" has confused patients, internists, primary care physicians, and dermatologists in terms of definition and significance. Many additional surgical excisions and repeated excisions have been performed needlessly because of an improper understanding of dysplastic nevi. A coherent, sensible classification of melanocytic nevi should be established.3,4
Craig G. Burkhart, M.P.H., M.D.
Medical College of Ohio at Toledo
Sylvania, OH 43560
cgbakb@aol.com
References
Naeyaert JM, Brochez L. Dysplastic nevi. N Engl J Med 2003;349:2233-2240.
Diagnosis and treatment of early melanoma. JAMA 1992;268:1314-1319.
Ackerman AB, Magana-Garcia M. Naming acquired melanocytic nevi: Unna's, Miescher's, Spitz's, Clark's. Am J Dermatopathol 1990;12:193-209.
Burkhart CG. Dysplastic nevus declassified: even the NIH recommends elimination of confusing terminology. Skinmed 2003;2:12-3.
Hussein MR, Wood GS. Melanomas, dysplastic nevi, and benign nevi: is dysplastic nevus a non-benign neoplasm? J Cutan Pathol 2002;29:570-571.
To the Editor: As a pathologist with an interest in dermatopathology, I cannot see how to support a diagnosis of dysplastic nevus or any other kind of nevus on the basis of the features listed as criteria in the legend to Naeyaert and Brochez's Figure 3, since all these features could be present in a melanoma as well. In fact, it is not possible to rule out malignant melanoma by examination of the specimen shown in Figure 3.
Francois Milette, M.D.
Centre Hospitalier Pierre-Boucher
Longueuil, QC J3V 5K7, Canada
francois.milette@rrsss16.gouv.qc.ca
To the Editor: Naeyaert and Brochez state that peak ultraviolet exposure occurs from noon to 4 p.m. I believe that is not correct. The sun reaches its zenith at noon, standard time. Therefore, the four-hour period of peak ultraviolet exposure occurs from 10 a.m. to 2 p.m., standard time. The sun reaches its zenith at 1 p.m. during daylight saving time, so the corresponding period of peak ultraviolet exposure during that period is 11 a.m. to 3 p.m.
David L. Keller, M.D.
Medical Institute of Little Company of Mary
Torrance, CA 90503
The authors reply: We agree with Burkhart that the term "dysplastic nevus" accounts for part of the confusion, but mainly for historical reasons, the term is still very popular. In clinical practice we prefer the term "clinically atypical nevus." In our article, we emphasize that clinically atypical nevi are associated with the risk of melanoma and that histologic melanocytic dysplasia has not been shown to be an independent risk factor for melanoma. We also state that clinically atypical nevi should be regarded as benign lesions that carry a low risk of malignant degeneration and do not require prophylactic excision.
The histologic criteria that we cite in our article are those that were used at a World Health Organization meeting attended by several dermatopathologists with great experience in the histology of melanocytic lesions.1 It is true that some aspects of these criteria can be seen in melanoma, just as some of the clinical criteria for clinically atypical nevi can be seen in melanoma. The lesion shown in Figure 3 in our article was diagnosed as a dysplastic nevus by an international panel of dermatopathologists,2 but Milette's remark illustrates the variability in histologic diagnoses for these lesions in daily practice and emphasizes the importance that consensus meetings and ascertainment of the possible benefit of markers for biologic behavior will have in the future.
The general advice to the public regarding exposure to sunlight is to be particularly careful with sun exposure two hours before and after the sun is at its highest point (noon, solar time), because then the flux of ultraviolet radiation on the earth's surface is highest. The closer one is to the equator, the higher the flux of ultraviolet radiation at a given time. Our recommendation to avoid sun exposure, particularly between noon and 4 p.m., reflects the fact that during the summer in Belgium, the sun is at its peak at 2 p.m.; the time of peak exposure will vary according to the location within the time zone.
Jean Marie Naeyaert, M.D., Ph.D.
Lieve Brochez, M.D., Ph.D.
Ghent University Hospital
9000 Ghent, Belgium
jeanmarie.naeyaert@ugent.be
References
Clemente C, Cochran AJ, Elder DE, et al. Histopathologic diagnosis of dysplastic nevi: concordance among pathologists convened by the World Health Organisation Melanoma Programme. Hum Pathol 1991;22:313-319.
Brochez L, Verhaeghe E, Grosshans E, et al. Inter-observer variation in the histopathological diagnosis of clinically suspicious pigmented skin lesions. J Pathol 2002;196:459-466.
The term "dysplasia" has confused patients, internists, primary care physicians, and dermatologists in terms of definition and significance. Many additional surgical excisions and repeated excisions have been performed needlessly because of an improper understanding of dysplastic nevi. A coherent, sensible classification of melanocytic nevi should be established.3,4
Craig G. Burkhart, M.P.H., M.D.
Medical College of Ohio at Toledo
Sylvania, OH 43560
cgbakb@aol.com
References
Naeyaert JM, Brochez L. Dysplastic nevi. N Engl J Med 2003;349:2233-2240.
Diagnosis and treatment of early melanoma. JAMA 1992;268:1314-1319.
Ackerman AB, Magana-Garcia M. Naming acquired melanocytic nevi: Unna's, Miescher's, Spitz's, Clark's. Am J Dermatopathol 1990;12:193-209.
Burkhart CG. Dysplastic nevus declassified: even the NIH recommends elimination of confusing terminology. Skinmed 2003;2:12-3.
Hussein MR, Wood GS. Melanomas, dysplastic nevi, and benign nevi: is dysplastic nevus a non-benign neoplasm? J Cutan Pathol 2002;29:570-571.
To the Editor: As a pathologist with an interest in dermatopathology, I cannot see how to support a diagnosis of dysplastic nevus or any other kind of nevus on the basis of the features listed as criteria in the legend to Naeyaert and Brochez's Figure 3, since all these features could be present in a melanoma as well. In fact, it is not possible to rule out malignant melanoma by examination of the specimen shown in Figure 3.
Francois Milette, M.D.
Centre Hospitalier Pierre-Boucher
Longueuil, QC J3V 5K7, Canada
francois.milette@rrsss16.gouv.qc.ca
To the Editor: Naeyaert and Brochez state that peak ultraviolet exposure occurs from noon to 4 p.m. I believe that is not correct. The sun reaches its zenith at noon, standard time. Therefore, the four-hour period of peak ultraviolet exposure occurs from 10 a.m. to 2 p.m., standard time. The sun reaches its zenith at 1 p.m. during daylight saving time, so the corresponding period of peak ultraviolet exposure during that period is 11 a.m. to 3 p.m.
David L. Keller, M.D.
Medical Institute of Little Company of Mary
Torrance, CA 90503
The authors reply: We agree with Burkhart that the term "dysplastic nevus" accounts for part of the confusion, but mainly for historical reasons, the term is still very popular. In clinical practice we prefer the term "clinically atypical nevus." In our article, we emphasize that clinically atypical nevi are associated with the risk of melanoma and that histologic melanocytic dysplasia has not been shown to be an independent risk factor for melanoma. We also state that clinically atypical nevi should be regarded as benign lesions that carry a low risk of malignant degeneration and do not require prophylactic excision.
The histologic criteria that we cite in our article are those that were used at a World Health Organization meeting attended by several dermatopathologists with great experience in the histology of melanocytic lesions.1 It is true that some aspects of these criteria can be seen in melanoma, just as some of the clinical criteria for clinically atypical nevi can be seen in melanoma. The lesion shown in Figure 3 in our article was diagnosed as a dysplastic nevus by an international panel of dermatopathologists,2 but Milette's remark illustrates the variability in histologic diagnoses for these lesions in daily practice and emphasizes the importance that consensus meetings and ascertainment of the possible benefit of markers for biologic behavior will have in the future.
The general advice to the public regarding exposure to sunlight is to be particularly careful with sun exposure two hours before and after the sun is at its highest point (noon, solar time), because then the flux of ultraviolet radiation on the earth's surface is highest. The closer one is to the equator, the higher the flux of ultraviolet radiation at a given time. Our recommendation to avoid sun exposure, particularly between noon and 4 p.m., reflects the fact that during the summer in Belgium, the sun is at its peak at 2 p.m.; the time of peak exposure will vary according to the location within the time zone.
Jean Marie Naeyaert, M.D., Ph.D.
Lieve Brochez, M.D., Ph.D.
Ghent University Hospital
9000 Ghent, Belgium
jeanmarie.naeyaert@ugent.be
References
Clemente C, Cochran AJ, Elder DE, et al. Histopathologic diagnosis of dysplastic nevi: concordance among pathologists convened by the World Health Organisation Melanoma Programme. Hum Pathol 1991;22:313-319.
Brochez L, Verhaeghe E, Grosshans E, et al. Inter-observer variation in the histopathological diagnosis of clinically suspicious pigmented skin lesions. J Pathol 2002;196:459-466.