Diagnosing pigmented skin lesions in general practice

Editor—The paper by English et al confirms a view that serial photography does not alter the final diagnosis of a skin lesion¹; a suspicious lesion that remains will require a biopsy to confirm the pathological diagnosis.

With serial photography it is difficult to obtain a standard image. The ambient lighting and other external factors change the view of the skin lesion—objective comparisons are therefore not possible. Furthermore, photographs may not differentiate skin lesions such as pigmented seborrhoeic keratoses and melanomas.

The dermatoscope is mandatory in evaluating a skin lesion and invaluable in helping differentiate a benign or suspicious lesion. Although lesions may be assessed visually, what is required is an objective assessment that can be recorded or photographed through the dermatoscope.² Had English et al performed their study by using the dermatoscope the results would have been of major interest. Unfortunately this study contradicts that by Del Mar et al and does not help primary care workers differentiate between benign and suspicious lesions.³

Figure 1.

Ackerman said that “no one should die of melanoma” as this mostly arises on the external skin.⁴ Therefore the principles to be applied when examining a patient with one skin lesion are that the skin is an organ and therefore the whole organ must be examined; a dermatoscope is a safe, non-invasive and cheap tool that is invaluable in differentiating suspicious lesions. These two principles will be of benefit in assessing skin lesions and enable a thorough evaluation of thu patient.