Transcription
Welcome. In this video, I'll be answering three key questions about basal cell cancers, or BCCs. What are they? How do you diagnose them when using a dermoscope? And what do you do when you actually find one in primary care? And if you make it to the end of this video, I'll be giving you a test on eight patients of mine. Why? Because your best teachers are your patients, but only if you choose to listen to them. Training a primary care [Music]. I'm Andy from the South Yorkshire Dermoscope Academy, where we help you become the great Primary Care Dermoscopist.
Course in sequence. So far, we've only covered capillary hemangiomas and sebaceous hyperplasia. Why a focus on BCCs so early on? Is because they are one of the most common cancers in humans. You will see them in a practice with around 10,000 patients, expect to see perhaps 28 basal cell cancers a year. And dermoscope is super good at identifying them. Plus, early detection enables them to be treated when smaller, reducing the morbidity your patients suffer.
First question: What is a BCC? It's a cancer of the basal cells of the basement membrane with a very low potential for metastasis. Histology shows islands or nests of basaloid cells. There are a few distinct clinical patterns. However, around 26 different flavors of BCC could be found on histology. The following patterns cover 99% of the BCCs I or you will see and a good starting point to mastering the identification of BCCs.
The most common type is nodular. These are a ball of cells gradually expanding in the dermis and epidermis. Thus, they tend to be raised above the skin surface. Growth rates vary from one study saying 0.83 mm per month, while I know the Primary Dermatological Society says 2 to 4 mm a year. But I think they can grow faster or slower. Can we diagnose them with the naked eye and touch? The answer is often yes. You may have been taught to recognize them as firm, pink papules, slow growing, often with a rolled edge. They can be confused with intradermal nevi, especially of the firmer mea type, and these are pink papules also containing vessels and a firm to touch. Dermoscope makes discerning one from the other much easier.
The second type you'll tend to see are the superficial BCCs. These are contained along the epidermal border. There is no dermal invasion. They tend to have well-defined borders and are usually flat. Superficial types when stretched can have a what's called a whip cord edge to them. Be suspicious of that red, well-demarcated, red, truncal patch that doesn't itch, is slowly growing, and doesn't respond to topical steroids or antifungals.
There's another group called infiltrative, sometimes called morpheic or sclerosing. And as the name suggests, the border extends further than you think and often give a white scar-like appearance clinically on the skin. Just to spice things up a little bit, you will actually find a combination of these types in any one BCC. So sometimes histology will return saying nodular and infiltrative, or superficial plus nodular. Using a dermoscope to identify the type of BCC is more than just an academic exercise. It enables you to choose a correct treatment option for that patient.
So, how do you diagnose them using a dermoscope? Well, firstly, don't rush to dermoscopy. Consider the whole patient first of all. The risk factors for BCC? Have they had one before? The older a patient is, the more common they are. But I've seen BCCs in a 29-year-old and a few in their mid-30s. And if the patient mentioned spontaneous bleeding, take it seriously. This is unusual for a benign skin lesion, but not uncommon with a BCC. Note its location, measure it, feel it. Is it firm or soft? And then have a guess what you think you'll see on dermoscope.
There's a key first rule to diagnosing a BCC on dermoscope, and it's a negative: there must be no pigment network. And if you see one, it's unlikely to be a BCC. The presence of a pigment network suggests a melanocytic lesion is more likely. So think again.
Let's now go through the six dermoscopic features that BCCs can display in two groups: four non-pigmented structures and two pigmented structures. This is your first task: learning to identify these structures through a dermoscope and understanding a little of their histopathological correlates. Oh, I do love that word, histopathological.
First up, arborizing vessels. Is where the vessels are clearly focused and branch from a wider stem to smaller branches. They can be small, medium, or large arbors. They are neovascular vessels surrounding BCC tumor nests in the dermis. However, they aren't pathognomonic for BCCs and can be seen in hypertrophic scars, epidermoid cysts, intradermal nevi, and others, including, of course, melanoma. A quick tip: it doesn't take much pressure from a dermoscope's faceplate with a contact medium to compress blood vessels, and in doing so, you can sometimes miss these arborizing vessels. If you can use polarized dermoscopy without a contact medium first, and then use contact medium later.
The other type of vessel that's common in BCC are small caliber, well-focused vessels. Of course, these are seen in other lesions as well.
Next, we have ulceration or multiple erosions. Ulceration is a full-thickness epidermal loss. These are often red and bleeding. Erosions are partial-thickness loss of the epidermis, and they often have a light crust. Well-demarcated, revealing their locations.
Next, we have shiny white structures. These are seen only with polarized dermoscopy. Shiny white structures, I have nicknamed "start worrying structures." In other lesions, shiny white structures are due to new or altered collagen bundles in the dermis, and they are a key dermoscopic sign for you to be able to identify confidently. It's one reason why a polarized dermoscope is better than having a non-polarized contact dermoscope. A hybrid dermoscope is better, as you can then flash the shiny white structures on and off to prove that these white structures you are seeing are only seen under polarized light. The shiny white structures in BCCs tend to be of the blotch and strand variety, due to mucin and changes in the stroma around the nests of basaloid cancer cells.
Our fourth and final sign for you to look out for in the non-pigmented category are "may globules." This is a short form: multiple aggregated yellow-white globules. Think that's a mouthful, and you'd be right. So, what does it mean? Multiple means more than one. That's an easy bit. The word aggregated is used a lot in dermoscopy, so let me define it now: three or more similar structures cluster together. In the building trade, this is stone aggregate. You will discover that in nevi, a common pattern is aggregated globules. But with these may globules, the globules are of a white-yellow color. They are composed primarily of areas of calcification.
We now move on to our two pigmented structures to look out for. Firstly, where does the pigment come from? It results from the presence of an increased number of melanocytes and melanin, mixed with the nests of tumor cells. The second thing you need to know is that the color you see when viewing melanin using a dermoscope changes according to its depth as follows: black if it's on the surface, brown if it's at the dermoepidermal junction, and a blue-gray color when it's in the dermis.
Dermoscopy loves metaphorical terminology. The first group are called leaflike areas, spoke wheel, and concentric circles. I group these together because they all represent aggregated, that word again, pigmented BCC nests at the dermoepidermal junction, branching from it but not going into the dermis. They are just different shapes, giving different patterns. I think it's easiest to show in a patient. This lady was in her '80s when she came to me with a few months' history of this linear scar-like area on her neck, but there was no history of injury. It wasn't bleeding, and there was no pain. It was about 1 cm long. Note the lack of arborizing vessels, but shorter, thin vessels. There are a few erosions with crust, but look at the periphery. These are what concentric circles look like, and there are leaflike structures. They are brown to a slight gray color. There are no spoke wheel patterns here, but two out of three isn't bad. How can we make sense of this? Here's the concentric circles, a leaflike structure, and a spoke wheel. They're all located at the dermoepidermal junction, and so are brown in color. Being named metaphorically, I feel able to attach my own labels to these patterns. How about we name the concentric circle looking like a seed, which gives rise to a leaflike structure, and if you're lucky, you're going to see a flower head? To me, these are all connected nicely together. What do you think?
The second type of pigment structure occurs when the pigmented nests of basaloid cells are deeper in the dermis. They are of a blue-gray color, and these come as small dots, bigger globules, or if they're large enough, we call them ooid nests. The dots tend to be at the dermoepidermal junction, but globules and ooid nests are within the dermis.
Now you know and understand these six structures. Let's line them up against each other and look at their associations to the different BCC types. Our contenders for tonight's top billing are in the blue corner: nodular BCC. In the red corner: we have superficial BCC. Round one: arborizing and fine vessels. Nodular BCCs tend to have arborizing vessels. Superficial BCCs tend to have the fine, short vessels. Round two: ulceration and erosion. Nodular claims the ulceration, but superficial fights back by claiming erosions. Round three: shiny white structures. This is a half-fought round. The judges call it a tie. It's seen in all types of BCC, and studies I have seen suggest between 30 and 70% will have them. So let's call it a tie at 50/50. Round four: may globules. Multiple aggregated yellow-white globules. It's a slam dunk for nodular here. They are not found in superficial BCCs. In nodular BCCs, they're found in around 21% and are very specific for a BCC. They are also associated with more infiltrative and aggressive forms of BCC. Around five: leaflike areas. Can these tip the balance back towards identifying a BCC as superficial? And yes, they can. These are considered 100% specific for a superficial BCC, full stop. They're located at the dermoepidermal junction and they aren't invading the dermis. See these and you have a diagnosis. Round six: it all comes down to this. Blue-gray dots, globules, and ooid nests. Since these are pigmented nests of basaloid BCC tumor cells in the dermis, these are firmly in the nodular camp. So nodular wins on a technical knockout.
Remember, the diagnosis of a BCC should not be based on a single feature, but on a set of dermoscopic features in combination with their clinical context. Histopathology is often essential and produces the final and decisive diagnosis.
So, you've had a look, you've taken a history, and you've decided this is probably a BCC. What do you do now? First, take a photograph. Why? Because when you make a referral, it's going to be so much better. A picture paints a thousand words. Second reason is for your own learning, because if you refer them, when you get the result back, you'll have forgotten what you'd seen. And if there's a photograph there, it can remind you, and you can learn through that process. The final reason why I think photographs are very useful is to help monitor change over time. An example would be this patient of mine who had a nodular BCC on his right temple. I referred him urgently due to its location, but not too week wait. I safely netted him, and in 4 months, he had not heard from the hospital. There was no appointment. I reviewed him, took another photograph, sent an update to the hospital, and he was seen and dealt with within a couple of weeks.
Secondly, tell your patients they have a mild type of skin cancer and it won't spread or kill them, but it's a nuisance that needs treating. Although I do remember on one lady with a small nodular BCC on her scalp, when I told her what it was, she only heard the word "cancer" and skipped the "mild" part and completely freaked out. Have a patient leaflet about BCCs handy, so when the patient leaves the room, they have something else to read.
Having taken a photograph and explained the condition to your patient, you've then got to decide on management. There are some high-risk areas for BCCs, and these warrant a 2-week wait. The high-risk areas tend to be around the eyes, the nose, the ears, and the lips. Small BCCs are more difficult to treat in these locations and often will cause more cosmetic damage and morbidity as a result. These therefore warrant a 2-week wait referral. Many BCCs are low risk. They're on the trunk or areas where they're not going to cause a great deal of harm very quickly, and these can be referred routinely. But I always safely connect carefully with my patients, asking them to report any new changes, and if they've not heard by so many months, to let me know and let me chase up the appointment for them.
Now, I'm going to answer that question I can tell you are just itching to ask me: Can GPs treat BCCs? Yes, but it's a bit beyond the scope of this video. I exercise low-risk BCCs and treat many of my patients with superficial BCCs with imiquimod and 5-fluorouracil creams very successfully. I think dermoscopy is that first vital skill to learn in a good Primary Care skin lesion service. Why? It leads naturally into supporting the other two: cryotherapy and minor surgery, where good patient selection is vital.
After all that, are you ready for a test? Then grab a pen and paper, and I'm going to present a to my patients. When the pause button appears on the screen, press the video pause button, and that will give you a bit more time to write what you observe. And the answers. Warning: not all these patients have a BCC. Here's the list of structures I want you to be looking out for and noticing. And if you can't recognize them, I think you need to go and watch the first part of this video again. And in fact, that's the great thing about a video: you can watch this video as often as you need to.
This 78-year-old gentleman with no previous skin cancer presented with a six-month history of this red patch which had nozed on his left upper arm. What structures do you see? Get ready to hit pause. There are clear arborizing vessels as well as fine vessels. I can't see any erosions or ulcers. If you watch the video, you'll notice shiny white structures. As I switch back and forth between polarized and non-polarized light, I can't see any may globules. And ignore this fluffy white artifact on my dermoscope. There is pigment network in his surrounding skin. These are solar lentigines. There are some dark dots which are brown, suggesting a shotgun pattern of pigment at the dermoepidermal junction. I'm not sure about leaflike structures, but maybe here. But look at this: a blue-gray structure. This means it's a nodular BCC.
This 81-year-old gentleman came to me having had a previous nodular BCC, having noticed perhaps 6 months before a patch on his left upper scapula. Press pause and identify the structures you can see. I hope what caught your eye on this patch is the most wonderful leaflike structures around the periphery. This means it is a superficial BCC. This is confirmed with the superficial erosions, a nice homogeneous pink background, and no structure suggesting any nodular element.
This 67-year-old lady, who's had no previous skin cancers, presented with a six-month history of this firm papule growing on her left forehead. What structures can you see? There's minimal in the way of vessels to see here, perhaps just a few fine vessels here. No ulceration, no erosions, no shiny white structures I could see, and no may globules. However, what really stands out is this scattering of brown dots, very much like it's been blasted with a shotgun. But again, look deeper. Can you see these blue-gray globules? And this is all consistent with a nodular BCC.
This 81-year-old gentleman with no previous history of skin cancer came to see a colleague. This pink papule had grown over the past four weeks on his filtrum above his upper lip. What structures can you see? Did you find any BCC structures? No. Then you'll be right, because there aren't any. Then, if it's not a BCC, then what is it? Note the vessels: most a dot with a white surround, but at the periphery, note a couple of hairpin vessels in places. So it's a keratinizing papule. Note the hair follicle. It's a wart, and after 30-second freeze, it dropped off 2 weeks later, leaving not a mark on his face. I can imagine without a dermoscope this being referred as a 2-week wait query BCC.
This 79-year-old gentleman, who had had no previous skin cancers, presented with a patch on the front of his chest, which I thought was a superficial BCC. A skin survey found these two other red patches on his lumbar spine. What structures can you identify? The upper lesion has many concentric circles all over, plus a few peripheral leaflike areas. It's got short, fine vessels. I couldn't see any shiny white structures, and no blue-gray or may globules. By now, I hope you can recognize a superficial BCC when you see one. The lower patch had shiny white structures and these brown leaflike areas, a couple of erosions perhaps, and I'm not convinced this is a blue-gray globule. There were no may globules and just some fine vessels. This is another superficial BCC, and in total, I found five on him.
This 37-year-old lady presented with a three-month history of a slowly growing nodule on her distal interphalangeal joint of her left hand. It had burst a few days prior to seeing me, and a few drops of clear gel had come out of the center. Can you see on dermoscopy? So on dermoscope, I hope you noticed some shiny white structures flashing on and off, and this suggests altered collagen, but this is common in any scarring within the skin. But beautiful fine arborizing vessels aren't there. This is a ganglion, and the clinical history and pictures should give you the answer, and it just shows you that dermoscopy has to be read in conjunction with the overall clinical picture.
This 64-year-old lady came to see a colleague with a six-month history of this intermittently bleeding small nodule below her left axilla. It was non-healing and had no previous skin cancers. He asked me to see it. Can you see on oscopy? So I think this is an interesting one. All you can really see are a couple of erosions, a homogeneous pink background, and then when I looked at it, slight blue-gray globules deeper. There are no blood vessels, no shiny white structures, nothing else. However, when I saw this in conjunction with a story of a non-healing, intermittently bleeding, I thought nodular BCC. I therefore, with permission, this was the first BCC I ever removed, and it proved that it was a nodular BCC. So what I learned from my patient here was that it's the constellation of features, not one feature, that gives you the diagnosis. It's the history in conjunction with the signs that you can see.
If you've made it this far through the video, you deserve my congratulations, and I hope you found these patients interesting. And I saved, in one sense, I think the most interesting for last.
This 85-year-old lady came to see me, a new patient at our practice. Her previous GP had seen this growing on her nose and had referred her routinely. It had been growing slowly for about 3 to 4 years, never bled, no pain, or anything, and she came to see me because it got a little bit larger. So, what do you think? So, what do you think? Exactly. First of all, note the makeup. I tried to clear her off as best I could, but she had makeup on it, which is what you find sometimes. Also, it's almost like a peanut, and there's a homogeneous pink background to it. You can't see a lot of vessels, just a few little short, clear vessels here. But on the right, look how dark that is. Look at all those different globules which amalgamate together. Is this a pigmented BCC or is it something else? But whenever you think pigmented BCC, because of the brown, blue globules, there are melanin and melanocytes within the dermis, always think of a melanoma. There's no shame in referring a pigmented BCC to rule out a melanoma. I therefore referred this lady 2-week wait, and on excision, it was actually a melanoma with a Breslow thickness of 2.2 mm. Now, this is very important. Please don't freak out that it's a melanoma. From what you've learned, you can see that there's something not quite right there. It doesn't fit a BCC with arborizing vessels and ulcerations or erosions and leaflike structures and all the other things that you've been seeing there. Certainly some pigment there. There isn't enough to give you a diagnosis for an obvious BCC. Therefore, always remember the first rule of dermoscopy and primary care: if in doubt, refer it out. And with this being on the nose, 2-week wait is very appropriate. If you follow the simple rules, you will not get into trouble.
What can I put on the shelves behind me to remind us of BCCs? I'm going to use these two orchids to remind us of the pigmented structures that give us a seed, concentric circles that give rise to leaflike structures, and then to a spoke wheel or flowerlike structures. These are also yellow-white flowers which remind us of may globules as well. And then, if you look at the stems, can you imagine them being red? Maybe those are the arborizing vessels. So I'm going to have these two orchids as a reminder of BCC. There you go. Thank you for watching. I hope you've enjoyed this, and I hope to see you again in the next video. Training a Primary Care Dermoscopist for every general practice.