This article is part of the 2019 Oncology Special Issue of Natural Medicine Journal. Read the full issue here.
Tina Kaczor, ND, FABNO, interviews Shauna Birdsall, ND, FABNO, on what clinicians need to know about skin cancers. From preventing squamous cell carcinomas to recognizing melanoma, Birdsall details the essentials of cancer-related dermatology.
This interview includes a broad review of what you can do to help patients prevent skin cancer. Do you remember the ABCDE’s of recognizing melanoma? Where do squamous and basal cell carcinomas usually occur? What is the ideal range for serum vitamin D? What other supplements have evidence for reducing the risk of squamous cell cancers? We cover all this and more in this in-depth discussion between integrative oncology experts.
Approximate listening time: 33 minutes
About the Expert
Shauna M. Birdsall, ND, FABNO, is a naturopathic physician and fellow of the American Board of Naturopathic Oncology. Birdsall graduated from National University of Natural Medicine in 2000. After completing a residency at Cancer Treatment Centers of America (CTCA) at Midwestern Regional Medical Center in 2002, she provided patient care and supervised naturopathic medical students there until 2008. She took on a leadership role at Western Regional Medical Center at CTCA in Goodyear, AZ, in 2008 and was later elected vice chief of the medical staff there. She also chaired the Medical Executive Committee, Credentials Committee, Peer Review Committee, and served as the Medical Director of Integrative Oncology until 2018. Birdsall recently joined Avante Medical Center in Anchorage, AK. One of Phoenix Magazine’s Top Doctors 2014-2018, Birdsall is strongly committed to providing individualized, compassionate, evidence-based care to empower and provide hope to cancer patients.
Tina Kaczor, ND, FABNO: Hello. I'm Tina Kaczor, editor-in-chief here at the Natural Medicine Journal. I'm talking today with Dr. Shauna Birdsall about skin cancers, and Dr. Shauna Birdsall has graduated from the National College of Natural Medicine in the year 2000. After that, she went to Cancer Treatment Centers of America, and she has been a specialist in integrative oncology since graduation. She's most recently taken a position at Avante Medical Center in Anchorage, Alaska, where she'll be providing patient care in a hospital-based setting. Shauna, thanks so much for joining me.
Shauna Birdsall, ND, FABNO: Oh, thank you for having me.
Kaczor: Dr. Birdsall, you've recently worked closely with a lot of dermatologists in a dermatologist setting, and you and I got talking about that. I was intrigued by a lot of the things that you learned, and I would like you to elaborate a little bit on how working closely alongside these dermatologists maybe changed your perspective of oncology and skin cancer specifically.
Birdsall: I have to say I was blown away, and this is a bit embarrassing. Working with patients undergoing chemotherapy and radiation for cancers like breast cancer and pancreatic cancer, I had always seen dermatology as more on the periphery. Working with dermatologists showed me how often dermatologists are diagnosing things like melanoma and really saving people's lives. It completely changed my perception around the integral nature of the specialty.
Kaczor: Yeah. I think that's what struck me, because you and I have parallel universes in the idea of our professions. We both graduated in the same year, and we've both been doing integrative oncology. I have to say I haven't worked closely with dermatologists. I share your inclination to say, "Ah, yeah, skin, we can catch that. No problem. We always catch skin cancer," and, I mean, that's despite the fact that of course we've both worked with people with metastatic melanoma.
We'll get to that and the importance of prevention, especially to prevent such tragedies as metastatic disease. I'd like you to give us a primer, and just give us a really basic overview for the clinicians out there on the types of skin cancers that there are, and who they most likely effect as well.
Birdsall: Sure. First of all, skin cancer is the most common type of cancer, and in the United States this year, more than 5 million people will be diagnosed with skin cancers. First and foremost, we like to talk about actinic keratoses. These are also known as AKs, and they are really precancerous lesions. You'll hear, the resounding themes of those that have sun exposure as being at risk for these cancers as I go on, but essentially actinic keratoses are often flaky or scaly patches of skin, and it's important that those are identified and treated, as sometimes they can lead to squamous cell carcinoma.
The most common type of skin cancer is basal cell carcinoma or BCC. This accounts for about 80% of skin cancers, and BCCs usually look like a flesh-colored pearl or bump, or a pinkish patch of skin. All of these skin cancers are going to be more prevalent in patients with fair skin, although patients with skin of all colors can develop these skin cancers.
Then, as I mentioned we're going to repeatedly talk about risk with sun exposure, and that means that the areas of the body that are most frequently exposed to sun such as the face, head, chest, arms and legs are going to be the most prevalent areas that you can see these cancers.
Squamous cell carcinoma is the most second type of skin cancer, and you're going to also see squamous cell cancers on areas like the rim of the ear. You really need to be able to make sure that those are identified, as those cancers can spread more deeply into tissues and cause additional damage, as well as metastasize elsewhere.
Melanoma, as we talked about earlier, is the deadliest form of skin cancer. It's actually been on the rise for the last 50 years. Melanoma in situ annual incidents in the United States is 9.5%, and in the United States melanoma has become the fifth-most common cancer in men and women. Melanoma increases with age, and you do see again the sun exposure and fair skin as common risk factors. I think later on, we'll talk about more risk factors for melanoma.
Kaczor: Yeah. That's an incredible statistic. Nearly 10% incidence for in situ melanoma. Wow.
Birdsall: Yes. Which is why I really started waking up to the issues with skin cancer detection and prevention, working with dermatologists, because I just was blown away, as I mentioned, with how often they were diagnosing either melanoma in situ or melanomas.
Kaczor: That's just checking. I mean, that's just skin checks, not coming in with that complaint.
Kaczor: Most of our listeners are practitioners that are primary practitioners. Very few are going to be specialists in skincare, of course. I'd like us to maybe, if you could, go through how to recognize melanoma, and maybe making sure that when we are seeing our patients ... and this could be in a specific skin exam, or it could also just be an incidental finding on their arm or their face or whatever. What are we looking for with melanoma?
Birdsall: Melanomas frequently develop in a mole or suddenly appears as a new dark spot on the skin. If you'll recall, we have the ABCDE warning signs, and I'm just going to go through those just for all of our review. A stands for asymmetry. B stands for border, either irregular, scalloped or poorly defined. C stands for color, varied really from one area to another in the same mole, and you can see shades of tan and brown, black, white, pink, red or blue. I think one of the most shocking melanomas that I saw was a melanoma inside the web of the toes in a patient that just looked like a little pink spot.
D stands for diameter. While melanomas are usually greater than 6 millimeters in size, which is the size of a pencil eraser, when initially diagnosed they can be smaller. E stands for evolving, a mole or a skin lesion that looks different from the rest or is changing in size, shape or color.
What is important to know as well is that melanomas don't necessarily read the textbooks. As I mentioned, they can look like something that, for those of us who are not dermatologists, may not look like something of concern, which is why I became aware of the need for annual skin exams.
Kaczor: Yeah. Yeah. It is remarkable that some of them don't look like much, and I think that erring on the side of caution, especially as our patients get older and older, because aging is a risk factor for all cancers, and I'm assuming skin cancer is included in there. Okay. Is there anything else? Last notes besides ABCD and E, and anything else that people should be looking for clinically before we close that discussion?
Birdsall: An area that's itching, bleeding. An area that opens up and appears to heal over, and then opens up again. Anything like that also needs to be evaluated.
Kaczor: Okay. Yeah. Referral to a dermatologist is simple enough that I think it's ... again, erring on the side of caution seems like a smart thing to do. We talked about melanoma, and experience shows us that of course it's the most likely to go somewhere. It's most likely to spread and become fatal for some patients, but I'm curious. Basal cell and squamous cell carcinoma, what is the risk of any local or metastatic disease with those?
Birdsall: In the majority of patients with cutaneous squamous cell carcinoma or basal cell carcinoma, the disease remains limited to the skin and with appropriate treatment is considered, "cured," which you and I both know we don't get to use that word very often in oncology. It's exciting that something can be cured with appropriate treatment. However, in 3 to 7% of patients with cutaneous squamous cell carcinoma, and rarely in individuals with basal cell carcinoma, local, regional or distant metastases can occur, which increases the risk for mortality or death.
Kaczor: Do you happen to know, is this analogous to melanoma in that the depth of the lesion has anything to do with it? Do you know?
Birdsall: Yes. For both basal cell and squamous cell carcinomas, both the depth and the size can contribute to risk, which is why even though a patient might only have a small spot, why it's important that it be caught early and treated, because left to its own devices, the larger it gets, the more at risk a patient is.
Kaczor: Okay. Well, that makes logical sense. As far as melanomas go, you mentioned in situ is nearly 10%. Are most of them still caught in the early stages, before they go anywhere?
Birdsall: Yes. Yeah. About 85% of melanomas are caught when there's only localized disease, so Stage I or Stage II at presentation, which as you and I both know, that's when you see the best survival rates. At diagnosis, about 15% have regional nodal disease, and only about 2% have distant metastases at the time of diagnosis. We're getting better at diagnosing skin cancers and melanoma, and it's theorized that dermatologists are more likely to biopsy these days because of seeing a higher prevalence.
Kaczor: I see. Okay. Can I ask one question? That is, in some states, including where I am in Oregon, naturopathic physicians can do minor surgery. The question I have ... I know my opinion on this, but I want to hear your opinion on this. It's not uncommon for shave biopsies to happen in-office. This is true of primary care physicians across the board, not just naturopaths. If someone suspects a melanoma, yea or nay on something like a biopsy of that, whether it's a punch biopsy or a shave biopsy?
Birdsall: Nay, and the reason is that there is research that the sooner after initial diagnosis ... so the sooner after initial biopsy ... that patient is able to get definitive treatment for their melanoma, the better. One of the risks, if someone other than a dermatologist or another health professional biopsies melanoma, is that there's then a delay potentially in getting the patient in to the provider that's going to be able to provide definitive treatment for that melanoma. That's one of the risks. Really, you want to see the highest level of specialty if you suspect a melanoma.
Kaczor: Okay. I think that needs to be reiterated time and again, because every once in a while you come across those patients, and your hair stands up when they tell you what first happened to their lesion, and you just hope that it didn't go anywhere. Okay. Let's talk about, again, we're talking to our audience is generally practitioners that are frontline folks, and which patient populations, which types of people, should there be particular vigilance for skin cancers, like higher levels of suspicion, and who exactly?
Birdsall: Okay. I warned you that we'd keep going back to a couple of things. Fair-skinned individuals, particularly those with blonde hair, red hair, lighter-colored eyes, blue eyes, although again, the warning that skin cancers can occur in patients of any skin color, and then that hallmark UV, exposure to UV radiation. More sun exposure, more risk. Also, however, living in sunny climates or higher altitudes, again because you're getting more direct exposure to UV radiation, as well as lower latitudes. Moles, patients that have more than 50 moles are at higher risk, and patients that have had a history of dysplastic nevi nearby or abnormal moles.
Patients with actinic keratoses are at higher risk. Patients with either a family history of skin cancer or a personal history of skin cancer, and immune suppression. I want to just take a moment to talk about immune suppression, because that can include a variety of different patient populations. That can include patients living with HIV or AIDS, or oncology patients that maybe are receiving chemotherapy or maybe their immune system hasn't recovered from prior chemotherapy, and it does include patients on immunosuppressive drugs such as for organ transplants. Patients who've had an organ transplant are at high risk for skin cancers because they're likely to have a lifetime of immune suppression because of those immunosuppressive drugs.
Lastly, exposure to radiation. You and I think of patients that have been exposed to radiation like breast cancer patients, lung cancer patients, et cetera. However, sometimes patients are exposed to radiation for skin conditions like basal cell carcinoma or eczema or acne, just different types of radiation. Then, exposure to chemical substances like arsenic can also increase risk, and then age increases risk. We're just at higher risk, the longer that we're living a lifetime out, being exposed to the sun.
Kaczor: Is it true that childhood exposures can have an effect decades later? Like someone who grew up down in San Diego, for example, but they live in Minnesota?
Birdsall: Yes, especially to melanoma. I am a-fair skinned person and I had an unfortunate history of a couple of different blistering sunburns, and that history of childhood sunburns and history of blistering sunburns can increase risk, especially for melanoma.
Kaczor: Okay. Yeah. That's good to have validated, because I've always heard that. Maybe in our patient intakes, it's something we should put on our intake forms. Not only where did you grow up, but did you get burned, sunburned?
Kaczor: Back in the day, of course, there was a time when people intentionally went out there and called a burn halfway to a tan.
Birdsall: That actually reminds me. I don't think of indoor tanning frequently these days, but exposure to indoor tanning and tanning beds. Maybe your patient is very responsible now as an adult, but maybe in their teenage years had a long history of exposure to tanning beds.
Kaczor: Yeah, yeah. It's something that's easily overlooked in an intake. Maybe we should make sure that that's top of mind. Let's talk a little bit about screening and prevention, and how can we make sure that we do catch things early, especially melanoma. What are the current recommendations, even, for skin cancer prevention?
Birdsall: It's interesting. As far as screening, it remains somewhat of a controversy, which surprised me. US Preventive Task Force is considered one of the authorities on screenings, and to date, the US Preventive Task Force hasn't found sufficient evidence either for or against skin screenings. What's interesting is there is a lot of debate amongst other experts in the field. The American Cancer Society actually recommends a cancer-related checkup every three years for patients between age 28 to 40, and then also encompassed in that cancer-related checkup is other kinds of screenings in addition to skin cancer screenings, and then every year for anyone over 40. Interestingly, the American Medical Association really sees it as individualized, and recommends that a patient should talk to their physician about frequency for skin cancer screenings, and those at moderate risk even should see their PCP or dermatologist annually.
The American Academy of Dermatology issued a statement regarding their disappointment over the recommendation by the US Preventive Task Force, and felt that the public should know that that recommendation that was neither for nor against annual skin cancer screening did not apply to individuals with suspicious skin lesions or those with increased skin cancer risk, and does not apply to the practice of skin self-exams. The American Academy of Dermatology recommends that patients really function as their own health advocate by regularly conducting skin self-exams and that if the patients see anything unusual, that they should see a dermatologist. Unfortunately, we all know that there's not always consistency with patients regarding advising for self-exam, and a patient can't necessarily see the back of their neck or their back, that may have had a lot of sun exposure. A number of dermatology providers still recommend annual skin exams, which after working with dermatologists, I'm definitely an advocate for as well.
Kaczor: Yeah. Yeah, that makes sense. All it takes is a few cases. We're all a product of our experience, right? You see a few cases where it could have been prevented, and it seems and it is tragic. What can we do? I guess once we identify patients who are at higher risk, due to either childhood or exposure or fair skin or immune suppression, like what can we do to prevent skin cancers?
Birdsall: Again, not to sound like a broken record, but decreasing sun exposure is the first thing. Interestingly enough, while I was just reviewing the research when I was preparing for our interview, I was looking at the Environmental Working Group and sunscreens, because there are definitely sunscreen ingredients these days that people have concerns about. For a patient that might be more holistically inclined, they might feel somewhat reluctant to put some of the ingredients that are in sunscreens on their skin, and so there's still a number of things that we can recommend. One is the physical sunscreens that are more of a barrier, and zinc oxide and titanium dioxide were considered generally safe and effective by the Environmental Working Group, and those are sunscreens with definitely friendlier ingredients that people may feel a lot more comfortable using and recommending. Secondly, wearing clothing shields our skin from sun exposure. There's some really interesting sun-protective clothing that is coming out as well if people are in the sun more frequently. Just trying to stay out of the sun during the peak periods or during high heat indexes is also something that patients can do as well. Then, doing annual skin exams. Because as you and I talked about, we may not feel concerned about a lesion that a dermatologist may instantly pick up on as something that may need to be further evaluated.
Kaczor: Yeah. On that note, I don't remember when I read this, but years ago I remember reading they did surveys of lesions, and they had primary care physicians and dermatologists assess them and see who was most accurate. Nobody bats a thousand, but it was remarkable how much better the dermatologists were at visually assessing lesions correctly.
Birdsall: Well, what was interesting working with dermatologists is I'd ask them why they were attracted to their field, why they went into dermatology, and they said because it's actually a field of medicine that you visually diagnose. You can visually see what's going on. Internal medicine, you might look at the results of a patient's lab work or a chest X-ray, but dermatology, you can actually see pathology and treat it.
Kaczor: Yeah. How interesting. Yeah, so I guess you're good at that. Some people are better than others, I think. We are naturopaths, and so let's talk a little bit about diet and supplements and other things that we can do. What can we do from a supplement standpoint? Is there anything we can add or anything we should avoid, for that matter, that could lower the risk of developing cancer, skin cancer specifically?
Birdsall: There was a really interesting Phase 3 randomized trial of nicotinamide for skin cancer prevention published in the New England Journal of Medicine in October of 2015, and in the study, 386 participants who had a history of at least 2 non-melanoma skin cancers ... again, that's basal cell carcinoma or squamous cell carcinoma ... in the past 5 years were randomized to receive 500 milligrams of nicotinamide twice daily or placebo for 12 months. They were seen by dermatologists every 3 months.
At the end of the study, the rate of new non-melanoma skin cancers was lowered by 23% in the nicotinamide group, and noteworthy was the fact that there was no benefit after the nicotinamide was discontinued. I would say about 70% of the dermatologists that I was working with recommended nicotinamide to their patients. That's actually compelling data from my perspective in regards to a supplement.
There's another supplement that has less research but is something interesting to watch called polypodium leucotomos, which is a fern from Central and South America. It was actually shown in studies to prevent both UVA- and UVB-induced toxicity and DNA damage. There was a study showing that 240 milligrams of a supplement containing that ingredient twice daily suppressed sunburn, and was found to extend the time outdoors before skin started to tan, so that's another possibility. I think we know as naturopathic doctors that vitamin C, E, zinc, beta carotene, omega-3 fatty acids, lycopene and polyphenols, especially in things like green tea, do also help to prevent free radical damage, which is what the exposure to UV radiation causes as well.
Kaczor: Okay. Yeah. Is there a specific role ... I don't I honestly don't remember where I have this idea from, so you can validate or invalidate my presumption ... about using vitamin A specifically for actinic keratosis?
Birdsall: Sure. There was a study on high-dose vitamin A reducing the incidence of actinic keratosis converting to squamous cell carcinoma, and the study looked at doses ranging from 25,000 IU a day, 50,000 IU a day and 75,000 IU a day. They did indeed find that that did prevent those AKs from turning into SCCs pretty significantly. However, from my perspective, there'd need to be a risk/benefit weighing of that for any particular patient.
Kaczor: Yeah. Because 25,000 to 75,000 IU daily for an extended period is ...
Birdsall: Correct. I had some concern after looking at that.
Kaczor: Yeah. Yeah. Recently, I mean, I generally wasn't too concerned with vitamin A levels as we gave them until ... because we would often use this dose for antiviral effects. Recently I came across a study that did suggest that high doses for prolonged periods actually can lead to or at least are correlated with fatty liver. I was a little surprised by that. I came upon it, of course, by way of patient care and doing a little due diligence. Anyways, that's just a little caveat
Birdsall: Right. I just am looking at that study and thinking about the fact that you would need to be on that long-term. I just had some concerns about using that particular amount of time.
Kaczor: Yeah, yeah. Not just the known, but the unknowns. Okay. Let's turn to vitamin D, because that whole "Do I'd get enough sun for vitamin D, am I getting so much sun that I'm increasing my risk of skin cancer," it seems to be a bit of a conundrum. On the same note and maybe in the context of this, is there a difference between sunburns and suntans and their link to skin cancer?
Birdsall: Okay. I think that there's definitely good evidence to suggest that vitamin D production from sun exposure poses too much of a risk for skin cancer. That's probably not the way that we want to be getting enough vitamin D, and there is more risk with a sunburn. However, suntans, our concept of tanning as being something that adds to our attractiveness, which I think in this day and age has faded with all the concern and the risk. Tanning does pose a risk too. That is still damage to your skin. Actually, as I was reviewing the research and thinking about this interview ... I'm just going to throw this in now, even though it's a little tangential and random ... if you have patients that are worried about the anti-aging, about the appearance of their skin, really the very best thing that they could do is to avoid sun exposure, to apply sunscreen, et cetera, because even that tanning still actually represents damage.
Kaczor: Okay. The vitamin D, what I hear you saying is it's best taken supplementally.
Kaczor: Because we have access of doing labs for our patients and such, is there an ideal dose to give, or do we base it on laboratory values? What is your opinion on that?
Birdsall: My opinion is that we need to base it on laboratory values, because there's so much individual variation on intake of vitamin D and the impact of that intake. One patient may consume a lot of dietary sources of vitamin D and actually be at perhaps not an optimal, optimal level, but not be deficient in vitamin D. Another patient may take some vitamin D supplements and actually get to pretty high levels of vitamin D pretty quickly. I think the only thing that we can do for our patients right now is to do lab testing.
Having said that, there is a lot of controversy over what the right values are, what the right range is. Again, when I was doing research just to make sure that I was totally up to date before we talked, it looks like people are in agreement over the fact that a 25-hydroxy vitamin D level below 20 nanograms per milliliter is considered deficient and does need repletion. We have more concurrence over that value.
What's still controversial is what is that optimal range? Is it between 30 and 40? Is it 50? What we do know is that vitamin D can reach toxic levels, and that that's not good either, and that there is more and more data on too high of a level of vitamin D posing risk. I think that that again argues for making sure that we're adequately testing our patients, because say they're deficient, we decide that they need repletion. It's still hard to monitor, without doing that testing, where they're at from a vitamin D level as you're doing repletion.
Kaczor: Sure. Sure. Yeah, I totally agree. I think that laboratory values should be just part of a routine lab for most people, given the many ways that vitamin D adequacy protects us from so many diseases.
My last question is having to do with those who know they have a family history of skin cancers, maybe even particularly melanoma, but skin cancers in general. Is it appropriate, I suppose, for certain patients with a strong family history to look at genetic predispositions and hereditary syndromes that include skin cancer?
Birdsall: That's interesting, again still a little bit of a controversy. We can test for a couple of genetic mutations related to melanoma. People who have a mutation on a gene known as CDKN2A have a higher risk of developing melanoma, pancreatic cancer, or a tumor of the central nervous system. A mutation on the gene called BAP1 means a higher risk of getting melanoma, melanoma of the eye or mesothelioma, and kidney cancer. However, the challenge is that if a patient carries a mutation on one of those genes, their lifetime risk of getting melanoma ranges from 60% to 90%. However, only about 10% of the people who develop melanoma have one of these genes.
What we do know is that we're still evolving our scientific knowledge of genetic mutations, and it's highly likely that there are additional genetic mutations that we just haven't found yet for melanoma. This is a really important conversation for a patient to have with their healthcare provider, or even ideally with a genetic counselor, who can counsel them on the risks and benefits of genetic testing overall.
Kaczor: Yeah. Yeah. Genetic counselors are a great referral for us to have, because we don't need to figure everything out and they have it all either at their fingertips or in their minds, so they're they're great professionals to ally with. All right. Well, I think that that's a really good survey and a nice review of reminders of things we may know, and maybe some things that are definitely new to our listeners. I can't thank you enough for taking some time and sharing your expertise with us today. Thanks, Shauna.
Birdsall: Thanks. Thanks for having me.
Kaczor: Take care.