Derm: Seborrhoeic Keratoses: Free MSRA Podcast

✅ MSRA Deep Dive: Seborrhoeic Keratoses – Spotting the Harmless vs. the Harmful

In this revision-focused episode, we dive into seborrhoeic keratoses (SKs) – one of the most common skin findings in clinical practice and exams. Although benign, they’re frequently confused with serious lesions like melanoma or basal cell carcinoma (BCC). We clarify what they are, how to spot them, and when to worry.

🧠 Key Learning Points

📌 Definition
• Common, benign epidermal tumours, often seen in older adults
• Have a characteristic “stuck-on”, waxy or wart-like appearance
• Also known as seborrheic warts

📌 Causes & Risk Factors
• Exact cause unknown
• Age is the strongest factor – more common with increasing age
• Genetic predisposition plays a role
• Sun exposure may be a contributing factor, but not directly causative
• Associated with other findings like dermatosis papulosa nigra (especially in darker skin types)

🔬 Pathophysiology
• Benign proliferation of immature keratinocytes in the epidermis
• Mutation in FGFR3 gene has been associated
• Not related to infection or malignancy

👨‍⚕️ Clinical Features
• Well-circumscribed, raised lesion with waxy, rough, or verrucous surface
• Colour: Tan, brown, black, or grey
• Typically painless, but may be itchy or irritated
• Most common on the trunk, face, scalp, or back
• Described as having a “stuck-on” look – as if pasted onto the skin
• May crumble if picked and can appear greasy

⚠️ Differential Diagnoses
• Melanoma – esp. nodular or amelanotic types
• Basal cell carcinoma (BCC) – esp. pigmented or nodular BCC
• Actinic keratosis – usually flatter and rougher, with sun-damaged background skin
• Key distinction: asymmetry, irregular borders, colour variation, ulceration, or bleeding → consider biopsy

🧪 Diagnosis
• Primarily clinical – classic appearance is diagnostic
• Dermoscopy can help – features like milia-like cysts and comedo-like openings
• If uncertain or atypical features → biopsy is necessary to rule out malignancy

💊 Management
• No treatment required if asymptomatic and diagnosis is clear
• Indications for removal:
– Cosmetic concern
– Persistent itching or irritation
– Secondary infection or bleeding
• Removal options:
– Cryotherapy (freezing)
– Curettage (scraping)
– Electrosurgery
– Laser ablation
• Avoid removal unless confident in diagnosis or malignancy ruled out

📈 Prognosis
• Excellent – SKs are completely benign
• Treated lesions don’t recur, but new lesions may develop in predisposed individuals
• No malignant potential, but important not to misdiagnose melanoma or BCC as SK

⚠️ Complications
• Not due to the lesion itself, but secondary to irritation
• Rubbing on clothing may cause itching, bleeding, or inflammation
• Picking or trauma may lead to infection
• Cosmetic distress in visible locations may impact quality of life

💡 MSRA Tip
If you're faced with a pigmented l

Episode Transcript

(00:00):
OK, let's unpack this. We're taking a deep dive today
into one of the, well, most common skin findings you'll see
seeber Heroic Keratosis. Think of this as a high yield
revision session. Absolutely.
We're aiming to boil down what you really need to know about
these lesions for your exams andfor practise, what they are, why

(00:20):
they show up and, crucially, what they aren't.
Right, because that difference is key.
O First things first, what exactly is a Cibaroic keratosis?
OK. So basically they're very
common, totally benign skin growths.
The really classic thing is how they look, often described as
having a stuck on appearance. Stuck on right?
Like it's not growing from the skin but placed on it.

(00:41):
Exactly, and they're typically raised, can feel a bit waxy or
sometimes quite rough, almost warty.
Colour wise they vary a lot. Light tan, brown, even very dark
brown or black. Got it.
Common, benign, stuck on. So why do people get them?
What's the aetiology? The risk factors.
Well, the precise cause isn't fully known, but age is
definitely the biggest factor. They just become much more

(01:02):
common as you get older. OK, age.
Anything else? Yeah, genetics plays a part.
If your family has them, you're more likely to get them to.
Sun exposure is often mentioned.Maybe is a contributing factor,
though perhaps not as directly causative As for, say, actinic
keratosis. Interesting, and you sometimes
see them alongside things like dermatosis, papulos and negra.

(01:23):
That's right, those small dark bumps often seen on darker skin
types. Seeing those might increase the
likelihood, suggesting some shared predisposition or
pathway. So age, genes, maybe sun, other
skin findings? What about the pathophysiology?
What's happening at the cell level, roughly?
It's essentially an overgrowth and abnormal proliferation of

(01:44):
the epidermal cells, the keratinocytes.
There are some gene mutations linked like FGFR 3, but for
practical purposes you just needto know it's a benign overgrowth
causing that typical appearance.An overgrowth of normal skin
cells. Just messy.
OK, now this feels really important clinically, especially
for exams. The differential diagnosis.
What else could it be? This is absolutely critical

(02:05):
because while SKS are harmless, they can sometimes look like
more serious things. You have to be able to tell the
difference. So what are the main ones to
worry about? The big ones, the ones you
cannot miss, are primarily Melanoma, especially pigmented
nodular Melanoma and sometimes pigmented basal cell carcinoma.
Actinic keratosis are another differential that they usually
feel rougher, more like sandpaper and are Slatter right?

(02:28):
Melanoma and BCC are the big concerns.
How do they differ generally? Melanomas often have more
irregularity. The asymmetry, border
irregularity, colour variation, maybe recent changes.
BCCS might look pearly, have tiny blood vessels or even
ulcerate. SKS tend to be more symmetrical,
well defined, and have that classic stuck on maybe slightly

(02:51):
greasy or warty feel. That stuck on feature keeps
coming up, so if you're unsure, especially if there are worrying
features, biopsy. Exactly.
Diagnosis is usually clinical based on that typical look.
But if there's any doubt, particularly if you're thinking
Melanoma or BCC, then a biopsy is needed to be certain.
Don't rely solely on the clinical look if features are

(03:11):
atypical. OK, clinical diagnosis, usually
biopsy. If unsure, what about
management? Do they need treatment?
Generally no, Since they're benign, treatment isn't
medically necessary. It's really only offered if
they're causing problems like itching, catching on clothes
becoming inflamed, or if the patient finds them cosmetically
unacceptable. And if treatment is wanted.

(03:31):
Options usually involve removal by a dermatologist, things like
cryotherapy, freezing them off, curettage which is scraping,
electrosurgery or sometimes laser.
Pretty straightforward procedures usually.
Makes sense and prognosis long term.
Excellent prognosis. They are completely benign, non
cancerous. Removing one gets rid of that
lesion, but people prone to themwill likely develop new ones

(03:53):
elsewhere over time. So they can recur, or rather new
ones can appear. Are there any complications to
be aware of? The complications aren't from
the SK itself being dangerous, but usually from irritation or
trauma. Like if they constantly rub on
clothing they can get inflamed, itchy, bleed.
Picking at them can also cause bleeding or, rarely, infection.

(04:13):
OK. So mostly nuisance factors,
right? Wrapping up then, benign.
Common stuck on appearance. Key differentials are Melanoma
and BCC. Diagnosis is clinical and less
uncertain. Treatment only as symptomatic or
for cosmetic reasons. That's a great summary.
Benign, but always consider the differentials.
For more free MSRA revision resources, visit freem-sra.com

(04:36):
and for the full premium revision tool, cut head to pass
them sra.com. So, final thought here, Given
how common these are, but how crucial it is not to miss
something serious, what's the single most important question
you should always ask yourself when looking at a lesion that
might be a seborrheic keratosis?