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10:46
A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data
Published on: December 9, 2015
Seasonal variation in dysplastic naevi.
M Welsch1, R Marszalek, M Young
1Department of Pathology, Milton S. Hershey Medical Center, Penn State University, Hershey, PA 17033-0850, USA. mwelsch@hmc.psu.edu
Clinical and Experimental Dermatology
|June 21, 2012
Summary
Seasonal sunlight exposure influences melanocyte markers in dysplastic nevi (DN). While dysplasia grading showed no seasonal difference, August samples had more Melan-A-positive cells, and January samples had more HMB-45-positive cells.
Area of Science:
- Dermatology
- Oncology
- Immunohistochemistry
Background:
- Sunlight exposure is linked to melanocytic neoplasms.
- Seasonal variations in melanocytic neoplasm incidence and excision exist.
- Understanding seasonal influences on dysplastic nevi (DN) is crucial.
Purpose of the Study:
- To investigate seasonal differences in dysplasia grading and intraepidermal melanocyte expression in DN.
- To compare DN removed in January versus August.
Main Methods:
- Dysplastic nevi (DN) were graded for dysplasia.
- Intraepidermal melanocytes were quantified using HMB-45 and Melan-A immunohistochemical staining.
- Cohorts from January (n=86) and August (n=85) were analyzed.
Main Results:
- No significant seasonal difference was observed in the grading of dysplastic nevi (P = 0.08).
- August samples exhibited a higher number of Melan-A-positive melanocytes (P < 0.02).
- January samples showed a greater number of HMB-45-positive melanocytes (P < 0.01).
Conclusions:
- Seasonal variations, potentially linked to ultraviolet light exposure, may affect melanocyte marker expression in DN.
- Despite differing melanocyte marker counts, the degree of atypia in DN did not vary seasonally.
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