rolex replica | fake audemars piguet | hublot replica sale | rolex replica sale

MELANOMA-SCREENING: Where are we today?

Dr Dagmar Whitaker, Dermatologist, Cape Town President of the Melanoma Advisory Board, SA

Melanoma is and has been for a long time a cause for serious concern in this country. We all know it's a deadly cancer, it's caused by the sun, it often occurs in patients with multiple nevi and prognosis entirely depends on early diagnosis.

The public is informed about the dangers of the sun and preventative behaviour such as sun avoidance, sun protective clothing and regular use of sunscreens. And still - despite all that - the impact of those campaigns does not seem to have altered the outcome as far as Melanoma Management is concerned: The incidence of Malignant Melanoma continues to rise despite all those warnings. It is estimated that at least 850 people continue to die each year from Malignant Melanoma and most of these patients are between 20 - 40 years.

To alter the outcome and prognosis there is only one promising strategy - and that is early diagnosis! Most general practitioners still base their diagnosis on clinical assessment of changes in colour, diameter, elevation and border (irregularity of outline) of a skin lesion, asymmetry of a lesion or a lesion different from other nevi. But one has to admit to shortfalls if one relies solely on clinical examinations because early diagnosis is almost impossible that way.

Most dermatologists use a dermatoscope which is a hand held skin surface microscope. This offers visualisation of subsurface structures of the skin with a 10 x magnification and offers a great improvement in diagnostic accuracy ­based on the examiner's experience.

But there is this vast group of patients with more than 50 nevi, some of them atypical may be even a family history of Malignant Melanoma, who warrant more specific diagnostic tools. These diagnostic aids are available since the mid 90's in the form of computerised digital Epiluminescence. Initially there was the Mole Max still widely used in many practices and the past 2 years saw the introduction of the Fotofinder. As times go by Technology develops and the quest for more accuracy and specificity is the driving force. The Fotofinder for instances does not only have a mole analyser for screening single moles but also a program for body mapping and dermoscopic skin cancer screening - besides offering documentation for cosmetic treatments for whoever engages in such.

The idea is to improve the distinction between benign and malignant melanocytic lesions using computer-aided algorithms. Unlike the initial mole mapping machine which base their analytic programs on the well established ABCD and 7 -point rule, newer machines like the Fotofinder determine additional characteristics most commonly found in malignant lesions. (I.e. if say "irregularity" is assessed the computer measures how much the smoothest border deviates from irregular areas). Structural characteristics and colour can be analysed most accurately.

Using diagnostic algorithms lesions are classified with a coloured scale and given a score which can be shown to the patient (i.e. ranging from white - nothing to worry about to red = high probability of being a Malignant Melanoma). The software program has got a diagnostic sensitivity of 86% with a specificity of 83%. These values compare to an accuracy only achieved by an experienced dermatologist with an interest in pigmented skin lesions.

Complete skin cancer prevention screens of course must include whether new moles have appeared since the last examination. Comparison of clinical images with the naked eye is time consuming and often does not give reliable results and is not easy if patients have multiple nevi.

To overcome this problem the Fotofinder has got a "body scan" program where 2 images can be compared and any change in colour is marked with a circle. One can then zoom in on these areas and assess the alterations. This combined software assures an excellent supervision and follow up of any risk patient.

Finally the introduction of florescence diagnosis adds value if one wants to diagnose non melanoma skin cancer (Basal Cell Carcinoma, Squamous Cell Carcinoma as well as well as Actinic Keratosis). It involves the application of a Photosensitising agent (ALA or Methyl ALA) which induces Porphyrin production in tumour cells which can be visible with a florescence lens.

This diagnostic tool can be used with or without the combination of Photodynamic therapy. The Fotofinder is user friendly and offers complete skin cancer screen with one system.

Patients and doctors likewise thrive towards best possible care and diagnostic accuracy and medicine without ever evolving and changes in technology is unthinkable! So with the quest towards perfection, the Fotofinder can be seen as the Doctors or Dermatologists third eye. But one has to remember: Even the most sophisticated technology does not replace clinic assessment. Only the use of all three diagnostic methods (clinical, reflected light microscopy and computer aided epiluminescence) will result in overall improvement in diagnostic accuracy.

COPYRIGHT (C) CAPETOWNDERMATOLOGISTS.CO.ZA. ALL RIGHTS RESERVED
Email Dr Whitaker