34th Hawaii Dermatology Seminar
Dr Christopher Zachary making opening remarks at this year’s spectacular meeting, which despite the recession has a 10% increases in attendence. With co chairs David Goldberg and Joe Fowler, Dr Zachary welcomed the attendees to the 2010 Hawaii Derm Seminar. Below, he reviews some of today’s presentations.
Day One – Melanoma
Stephen Dusza MPH gave the audience a clear and engaging review of ‘Targeted Screening; What is the Evidence That it Works? Screening per se, is only useful if planned, costed, and analysed carefully. Screening tests need to be highly sensitive, and followed by tests of a highly specific nature. The UK experience indicates that once you start screening, there is likely a sequential increase in diagnosis; but the question one needs to know is ‘will this necessarily be followed by a decrease in mortality?’. Lead time bias (diagnosing earlier) and length bias (the longer you observe a population, the greater the chance you will find morbidity and mortality) can lead to misinterpretation of the findings. These screening programs can be confusing, and for many conditions, although initially there will be an increase in the rate of diagnosis, this climbing incidence will moderate with the stability of the screening program, and the mortality will likely remain the same.
While cervical cancer mortality has dropped 50% since screening started, there has been considerable morbidity associated with the screening program including personal anxiety, biopsy and other surgical procedures. Sadly, lung cancer screening has not changed the mortality rate, but has increased the morbidity of subjects tested in terms of investigations, including bronchoscopy, biopsy and so forth. So what is the point of non-targeted screening ? Very little by all accounts ….. Weighing the costs of screening in comparison to the benefits gained, it may actually be deleterious to the population at large, and with little if any benefit.
A recent well known article, Melanoma epidemic; a midsummer night’s dream? suggested that despite the extensive melanoma screening programs, the overall mortality from melanoma has not changed. So what’s the point? Surely we need to be more clever, and learn from these expensive mistakes, particularly when the cost of medicine is going through the roof.
So the new thinking is that targeted screening makes sense. Much of the increase in melanoma occurs in those over the age of 50 yrs. Presence of common or atypical nevi are strong indicators for development of melanoma. Targeted screening is much more cost effective, and visual screening of these selected ‘targeted’ populations might be performed every two years with dramatically lower costs, and much higher pay off at the other end.
It’s clear that early intervention is associated with better outcomes. But the public’s ability to perform self skin exams are not good, and their ability to recognize themselves as ‘high risk’ is quite poor, even though one might think that the Melanoma Monday campaign with its ABCDs of melanoma recongnition should have beed relatively simple, and more successful. The public’s awareness is not limited to the ignorant either ….. awareness of the ABCD rules of melanoma or use of sun block in spouses of those with a history of melanoma is very low. Melanoma screening by primary care physicians is very low. And we, the physicians, need to take some stick here also …. the median wait time for a melanoma consultation in Miami 28 days, for botox is 8 days.
In general, cancer screenings have become much more targeted, an melanoma should be no exception.
James Grichnik MD discussed Melanoma Risk Factors – Old and New
It’s well established that the risk for developing melanoma is significantly related to having dysplastic nevi and mole density. Mole counts indicate that the more moles you have the greater the relative risk of having melanoma (chance of malignant growth). Also with atypical nevi; the greater the number, the higher the risk. Essentially, more moles, more risk; more atypical moles, much more risk (up to 10 times).
Complex dermoscopic pattern is an independent risk factor for melanoma. The more complex, the higher the risk. Furthermore, the gene sets of these moles are indicative of risk for melanoma. Large congenital nevi in the US are associated with tremendous increase in melanoma. For some reason, this doesn’t seem to bear out in Asians.
Sunburns are clearly associated with melanoma. Not only if you get them, but when you get them. Childhood burns more likely to produce melanoma than in adults. This is probably a timeline issue, as maybe takes30 years to develop melanoma. The question of chronic sun exposure is more complex, more related to lentigo maligna which is clearly a different player. The roll of tanning beds; with the data still coming in, it’s clear that burns are associated with increased rates of melanoma. The anti-tanning laws are reaching the govenors’ desks (at last).
Socio-economic status : more affluent more likely to get melanoma. Possibly because they can afford to fly to sunny climates for vacations, etc. Pilots are said to have increased incidence of melanoma. Renal transplant patients are at increased risk, with a 3.8 fold increase in US, but not in Sweeden. Possbily related to sun exposure. Phenotypes, fair skin, freckles, fair vs dark skin, hair, eye color all 2-3 times the risk. Melanoma family history very significant. 13 % of primary melanoma patients have one first degree family member with history of melanoma, and 5% have two parents with history. Specific genes have been found in certain families with high incidence of melanoma inlcuding MC1R melanocortin receptor, ASIP gene, Tysosinase TYR, and others … all associated with increased incidence of melanoma. Number of Mitoses in pathology specimens is associated with risk for recurrence; Higher # of mitoses, higher risk.
Ashfaq Marghoob MD discussed Techniques for enhancing the process of early detection.
Tumors are being diagnosed much earlier, and that’s good. Evolution in thinking allows us to recognize melanomas much earlier. Be aware that the patient’s history is very important ….”lesion feels funny” in a clinically normal appearing lesion is worth biopsying.
Analytical recognition would include the ABCDs of tumor recongnition, and remains important.
Differential recognition, including the ugly duckling sign. “One that stands out as being different” probably is different and is worth subjecting to more specific analysis. And you don’t have to be a physician to discover an ugly duckling. Derms, Experts, Nurses, Staff, even one’s 12 year old children can score highly on this test.
Comparative recognition: Change is the most significant indicator of melanoma, adding “E” for evolution to ABCDs. 1-3% of these changing lesions are melanomas, ie specificity is relatively low, but is important nevertheless.
How good are specialists at diagnosing melanoma based on visual examination alone? Technology has led to the recognition of previously ‘normal’ lesions. Dermoscopy helps evaluate troublesome lesions, helps specificity. Once your brain has recognized “normal” with a dermatoscope, you can be pretty sure that the lesion is indeed benign. Allows dramatic reduction in the need for biopsy.
So why is it that there are times you just know something, without being able to explain how you know it ….. this ‘gut feeling’ is part of the primitive brain, a vital part of learning that is as much a part of apprenticeship as it is releated to didactic or formal training. It resides outside the reach of awareness, in basal ganglia region (amygdala), is responsible for that gut feeling or intuition that you know something is right. Silent, implicit or passive learning. Unable to articulate why you feel the way you do about recognition of something that you think might be abnormal. There is an emotion associated with memory stored. If you encounter a pigmented lesion that troubles you, even though it might not have any red flags (ABCDs), you should consider removing it. Go with your gut!
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