Hensin Tsao, MD, PhD
Dr Hensin Tsao, Director of the Melanoma Clinic at Massachusetts General Hospital, lead off the 2013 Maui Derm meeting by providing the audience with an overview of some of the top stories in dermatology in 2012-2013.
Dermatologists should know that melanoma is the 5th most common cancer in males and the 6th most common cancer in females affecting one in 36 men and one in 55 women. Most of these numbers are not including melanomas in situ, which would then most likely make the numbers higher. (American Cancer Society 2012)
Unfortunately, melanoma incidence and mortality continue to increase. There is also a disparity in survival among races, i.e., African Americans tend to have a survival disadvantage compared to whites and other races, especially in Stage III.
Another interesting fact is that there are twice as many deaths from melanoma for men than for women; therefore, there is a thought that there is a female survival advantage. Based on the graph below, one can see that the mortality for rate for males, after age 65, really begins to take off. There appears to be some sort of lethal phenotype associated with melanoma in elderly men, especially in the head and neck. This is a group to whom one should pay particular attention.
A study in the Journal of Clinical Oncology demonstrated a superior outcome of women versus men with Stage I/II cutaneous melanoma. This was based upon a pooled analysis of four European Organization for Research and Treatment of Cancer Phase III trials.
The bulk of the effect appears to come from the tumor thickness (especially in tumors greater than 2 mm). Overall, males seemed to do worse than females.
When the studies are aggregated, almost every study conducted around the world shows a hazard ratio of approximately 0.6 to 0.7. This is consistent across many studies; therefore, this does not show a detection or reporting bias.
- Melanoma incidence and mortality rates continue to increase
- There may be a disparity in survival between races
- There appears to be stronger evidence for a “female advantage” in survival although biologic basis is unclear
- Unlikely reporting bias since it has been observed worldwide
Another hot topic is that of blood-borne viral infections linked to tattooing. Most of the time it is due to the tattoo artist being substandard in hygiene. Recent studies have demonstrated that M. chelonae infection has been associated with tattoos. Molecular analysis showed M. chelonae was found in 11 clinical isolates and in an unopened bottle of ink. 18 out of 19 patients responded to macrolides and or doxycycline depending on sensitivities. It should be noted that contamination likely occurred before distribution.
For Dermatologists, there appears to be a need for better oversight and record keeping.
Sun avoidance is a crucial component of all skin cancer prevention campaigns. Scientists have begun to study the effects of direct light, diffuse light, and reflected light. Modeling revealed that a large amount of diffuse UV radiation occurs. Recent studies indicate that direct UV occurs mostly on exposed sites during summer months; reflected irradiation occurs during winter months.
SimuVEX software was utilized to estimate UV from various ambient sources. Diffuse radiation accounted for 75-85% of the annual sun exposure. It is not clear whether or not shading can protect against diffuse light.
The WHO has classified sun lamps as a carcinogenic agent. The true morbidity of tanning bed use is an area of intense scrutiny and better estimates are emerging.
The British Medical Journal published a meta-analysis (27 studies) in 2012 looking at cutaneous melanoma and its association with sunbed use. This study found that there is about an 87% increased risk of melanoma if tanning [beds] are first used before age 35. There is an element of dose-dependence associated with the use. This is becoming a significant public health problem as tanning bed use now contributes to about 10% of melanomas. As expected, the risk of melanoma with tanning bed use is independent of latitude. Public health response is more aggressive these days, but we’re not there yet.
Natural Disaster Dermatology
Murcormycosis is a rare infection caused by molds that are ubiquitous in soil, decaying wood and organic material and if left untreated, it can lead to massive tissue necrosis. Although it usually occurs in immunocompromised patients, the fungus can develop after trauma in the immunocompetent patient.
A 2011 study looked at necrotizing cutaneous murcormycosis after a tornado in Joplin, Missouri. The study found that of the 13 patients with murcormycosis, five patients died; four out of the six patients were not treated with Amphotericin B and one out of seven patients treated with Amphotericin B died.
What are the risk factors that lead to mortality after infection?
- Number of wounds that were punctured
- Outbreaks of rare saprophytic infections after catastrophes have been reported
- All 13 cases had DNA evidence of Apophysomyces trapeziformis
- Infection needs to be considered early so proper treatment with AmphoB can be instituted
- Increased number of puncture wounds, early signs of rhabdomyolysis