The melanoma epidemic. Excess exposure to ultraviolet light is established as major risk factor

Skin cancers in skin types IV-VI: Does the Fitzpatrick scale give a false sense of security?

The Fitzpatrick scale has been in use for skin colour typing according to the tanning potential of skin since its inception in 1975-1976. Thomas Fitzpatrick developed the scale to classify persons with 'white skin' in order to select the correct amount of UVA in Joules/cm² for PUVA treatment for psoriasis. Since then, it has been widely used in Dermatology to gauge the skin's reaction to UV exposure, tanning potential, assessment of sunburn risk and amount of sun protection required for individual patients. However, the use of this scale has been of limited utility because of different self-perception in different areas of the world, particularly among those with skin of colour. Skin cancer risk is loosely inversely correlated with the initial genetic/inherent amount of melanin (most research has focused on eumelanin) present in the skin, although the pattern of exposure and amount of UV radiation required causing DNA damage varies widely according to different cancers. In this review, we have shown that the Fitzpatrick scale is neither correct nor adequate to reflect sunburn and tanning risk for skin of colour. Therefore, it may give both patients and physicians a false sense of security that there is little risk that people of colour can develop skin cancers. We have reviewed the small but not insignificant risk of skin of colour developing skin cancers and emphasise that there remains much research that needs to be done in this field.

The melanoma epidemic: res ipsa loquitur

Many have debated whether or not we are in the midst of a melanoma epidemic. Some facts are clear and helpful to this debate, while others are less clear. The incidence and mortality of melanoma have increased over the last several decades, but the incidence has risen faster than the mortality. The incidence has risen 3%-7% on average over several decades and even more rapidly among Caucasian men and the elderly. In the U.S., the incidence in men is higher than in women after the age of 40, and the difference between men and women increases from age 40 until the end of life. The incidence in the U.S. has risen most rapidly among in situ and localized lesions, but distant and regional disease have increased as well. Among localized disease, in the U.S. from 1988-1997, all stages increased by comparable amounts. This strongly argues against the idea that the increase in incidence of melanoma is only due to early detection of thin lesions or biologically benign lesions, at least during the time period studied. On the other hand, early detection of thin lesions may well account for lower increases in mortality than incidence and improvements in survival. Survival has increased from approximately 60% in the 1960s to 89% in recent years. Improvements in survival appear to be related to earlier diagnosis, rather than an improvement in survival of a given stage. Studies consistently point to a major role for UV light exposure as the most important risk factor for those individuals with a phenotypic susceptibility. Public health efforts aim at primary and secondary prevention strategies. Primary prevention strategies attempt to prevent people from developing melanoma, primarily through avoiding exposure to UV light. There is a particular emphasis on avoidance of UV light exposure in childhood and young adulthood, when it appears the risk is greatest. When strict avoidance cannot be adhered to, sunscreens have been logically recommended. Secondary prevention strategies include screening campaigns and educational campaigns. Many of these strategies appear promising but require further rigorous testing. The melanoma epidemic has arisen for a variety of reasons including: a true increase in melanomas of malignant behavior, a particularly high increase in localized and in situ lesions, and an increase in the number of biopsies performed, which may have resulted in an increased detection of less aggressive lesions. The contribution of possible changes in the diagnostic criteria for melanoma to the increased incidence remains unknown.

Lymph node sonography versus palpation for detecting recurrent disease in patients with malignant melanoma

The aim of this study was to examine the efficacy of lymph node palpation versus high resolution lymph node sonography for the detection of lymph node metastases in patients with malignant melanoma. We retrospectively evaluated 2256 pairwise lymph node examinations of the cervical, axillary and inguinal region by palpation and sonography in 264 patients with resected melanomas greater than 0.75 mm of invasion thickness. Lymph node metastases occurred in 50 patients (19%) which were detected in 38 (76%) by both methods in agreement. In 7 cases (14%) palpation failed, in 3 cases (6%) sonography failed and in 2 cases both methods failed to identify metastases. The overall sensitivity of detecting metastatic disease was 82% for palpation and 90% for sonography which was statistically not different. The overall specificity by sonography (99%) was significantly better than for lymph node palpation (88%). Taking into account the results of this analysis, we conclude that patients with a negative result by lymph node palpation do not need further sonography for verification. However, any suspect result by palpation should be additionally evaluated by lymph node sonography in order to rule in or out metastatic disease.