Basal and Squamous Cell Carcinomas

by Stuart Enoch, PhD

My Notes
  • Required.
Save Cancel
    Report mistake

    00:01 Xiaflex. Amputation, you can use it as a last option.

    00:04 So the answer has come up. I'll just go through this. BCC can arise in a chronic pressure ulcer, true or false? What can arise in a chronic pressure ulcer then? Marjolin’s.

    00:17 It’s called SCC. BCC doesn't metastasize. Immunosuppressed patients are highly more prone to develop SCC not BCC. And BCC is normally excised at 3 cm margins - true or false? 5 cm margins? 3 mm margins. So it’s normally excised at 3 mm, not 3 cm? So here again, you got the answer there. But is that malignant or not? Keratoacanthoma? No, it is carcinoma in situ. Some pathologists says a well defined squamous cell carcinoma.

    01:02 Early, early stage. Its not pre-malignant at all. I'll tell you why. In keratoacanthoma, the course is, it grows very rapidly over say 4 to 5 months. Then it plateaus off for 3 to 5 months. Then it reduces in size and disappears completely. But in some people, that can stay and become a SCC. Okay, so it is not a benign condition, it is a carcinoma in situ. Actinic keratosis is pre-malignant. Others are not pre-malignant. Yes, pyogenic granuloma in trauma, somewhere the digit, you get a hematoma, it's neither pyogenic nor a granuloma. But they call it pyogenic granuloma. It's just a bit of hematoma. Just don't get mixed up between seborrhoeic keratosis and actinic keratosis. This is where we see people getting confused between those two. Seborrhoeic keratosis is benign, that's just stuck on lesions. You see in elderly people. Actinic keratosis also called solar or senile keratosis is a pre-malignant lesion.

    02:32 Okay. All these are risk factors for SCC, sun exposure, ionising radiation, drugs, papillomavirus, hydrocarbons.

    02:51 You can't distinguish between the three, sun exposure, exposure to sun tanning, sun tan. You can get any of the three cancers.

    03:08 It's very difficult to say you're getting melanoma, you're getting SCC. Usually, I take a point, sailors, people who have been working in the sun for 50 years, they end up with a SCC or a BCC. But they can always -- But sometimes you get more melanoma? Yeah because it's much more intense. Intense. But I would say to be bit more careful.

    03:29 You can also get an SCC from the sun bath. Yeah and you can get a melanoma in a sixty year old who has been working in Middle East for twenty five years. So yeah.

    03:43 I won't waste too much time on this. What do you think the diagnosis are? What are the options with that that sort of history? Melanoma, BCC, nodular BCC. SCC I wouldn't go, normally BCC, melanoma. Then a pyogenic granuloma, hematoma. These are your diagnosis. SCC you wouldn't get it that way. SCC will have the classically everted edges.

    04:13 BCC, treatment of BCC? Excise. Surgical excision. Three to five mm is fine.

    04:19 Does it depends on the initial size as well? That's for SCC, it depends. For BCC, it doesn't depend on the initial size, it depends on the type. If you have a nodular melanoma, BCC, 3 mm is fine. But then there is something called morphic BCC, where the margins are indistinct.

    04:38 Then you have to take wider margins, in morphic. But three to five mm is safe for an exam. Okay, this is a classical BCC. This is a classical BCC with a central crater, and rolled over edges. Central crater and rolled out edges.

    05:00 So this is what the history they will give you. Eyelid, somewhere around that area, with a central crater, and everted edges. Types of BCC are superficial, nodular, ulcerative, infiltrating, morphic. But, what do you think this might be? Ulcerative. Ulcerative BCC.

    05:22 Now, this is a keratoacanthoma.

    05:28 This is a keratoacanthoma. It grows so rapidly, you're pretty much unsure what to do next.

    05:35 But then with experience, you realize that it also shrinks quite quickly. By one year, this would have completely disappeared. So duration, progression, sun exposure, they'll ask the differentials of keratoacanthoma? It could be a SCC. So if you are unsure of the diagnosis, what do you do? Punch or incisional biopsies. Wait and watch. Biopsy, if you're unsure.

    06:03 Now this keratoacanthoma is slightly annoying in the exam, because you really don't know what to answer. There's a school of thought where they say wait and watch, this is a KAA, it will disappear. But then other people think, how do you know it's a KAA unless you do a biopsy? How sure are you? Imagine that's an SCC, and you leave it for a year. They will end up with all sorts of metastasis.

    06:28 Okay. So if you get a keratoacanthoma in the exam, just look at the options very carefully, what are the things they have? If they have a biopsy option, go for it.

    06:40 This is a SCC. Diagnosis, you do an incision biopsy first. Then you examine the lymph nodes and then you do the wide local excision. Amputation of the ear, and neck dissection.

    06:59 That’s what we discussed in the morning. Reconstructive surgery? Yeah, in elderly patients it’s very difficult to reconstruct, you know you are excising all of this. So there's probably nothing much you can really do now. You probably have some artificial ears. Biopsy is the gold standard for diagnosis of BCC. Three options are punch, incision or excision. Excision is when you excise, and you're sure that you can close the primary. Otherwise if unsure, go for punch or incision.

    07:38 You need to know this because there are questions which will ask you excision margins of BCC, three to five millimetres. Infiltrative or morphic, you may need a slightly larger margin. Squamous cell carcinoma, well defined tumour, less than two centimetres, you go for four millimetre margin. More than two centimetre, that's the size of the lesion, you go for six millimetre margin. Poorly defined, one centimetre. If the tumour is two centimetre diameter, if this is two centimetres, then you take four millimetres. If this is a four centimetre tumour, big one, you take six millimetres.

    08:35 So, what we normally teach is, for a BCC, have in your head as three to five millimetres.

    08:47 For an SCC, have it as six to ten millimetres. So pretty much double. Always think double for SCC. I'm sure you know the diagnosis. It's a melanoma. This is what we are are coming at. Other things you need to examine are the lymph nodes and the abdomen. Okay management of that patient. If you're asked a scenario, what you do next? The answer is do an excision biopsy. Never mention core, incision. Nothing for melanoma, always excision biopsy. If you try to do a core biopsy, you'll distort the entire architecture. Okay, so what do you do after you excise with two millimetres? What’s next? Breslow thickness. Then your further management depends on the Breslow thickness, which I'll come to the next slide. Until you get the Breslow thickness, if you can close the wound directly, close it. Otherwise you leave it open.

    09:55 Okay so, asymmetry. B is what? Borders or bleeding, Colour variegation. Diameter more than six millimetres, diameter expanding more than six millimetres. Elevation. Ulceration, satellite lesions. Six millimetres halo and irregular borders.

    10:20 Now, I put this slide just to give you another type of question they ask, what are the features in a histology that will suggest malignancy? What are things you look for in histology? Mitotic count, yes, very good. Anything here? Areas of haemorrhage and areas of necrosis. Invasion to adjacent structures. What else? Nuclear-cytoplasmic ratio. The nucleus will expand, becomes larger. So these are things you need to look for in histology. Specifically for melanoma, these things. But you don't really have to go into the details of knowing it. But if you have a question related to differentiating between a benign lesion and a malignant lesion, the things to be looked for are mitotic count, areas of haemorrhage and necrosis, areas of direct invasion, breach of the basement membrane and nuclear-cytoplasmic ratio.

    11:31 Now, we've done that. We've done an excision biopsy. Leave that for one

    About the Lecture

    The lecture Basal and Squamous Cell Carcinomas by Stuart Enoch, PhD is from the course Medical Scenarios.

    Author of lecture Basal and Squamous Cell Carcinomas

     Stuart Enoch, PhD

    Stuart Enoch, PhD

    Customer reviews

    5,0 of 5 stars
    5 Stars
    4 Stars
    3 Stars
    2 Stars
    1  Star