Skin Surgery JC081: Skin Ulcers: Skin And Subcutaneous Lesions, Skin Cancer Flashcards
Skin and SC lesions
- Common
- Patients’ worries
—> unknown nature
—> malignancy
—> appearance
Diagnosis:
- Sometimes obvious
- History + P/E follow
- Regional exam + Systemic review as indicated
- Lesion may represent an ***occult systemic problem
History taking of Skin + SC lesions
- Onset
- Progression
- Pain
- Discharge / Bleeding / Ulcer
P/E of Skin + SC lesions
- Site, Size, Shape, Colour
- Consistency, Surface, Border
- **Tenderness, **Temperature (infection, inflammatory)
- ***Pulsatility, Emptying (vascular lesion)
- ***Skin / Deep fixation
- ***Transillumination (cystic lesions)
Management of Skin + SC lesions
- Observation / Reassurance
- Excision / Destruction (e.g. shave, liquid N2)
- ***Excisional biopsy (suspicious lesions)
- ***Incisional biopsy +/- Definitive treatment (unknown nature)
- ***Wide excision +/- Reconstruction (malignant lesions)
- Radiotherapy
Skin structure
- Epidermis
- 3-5 cells thick
- Impermeable stratum corneum - Dermis
- 0.8-2.5mm thick (depends on location)
- fibrous + tough - Hypodermis
- indistinct loose fibrofatty layer
- contains ***adnexal structures (vessels, hair follicles, sebaceous glands, sweat glands) - SC fat
***DDx of Skin + SC lesions
- Epidermis
Benign:
- Skin tags
- **Warts
- **Seborrhoeic keratosis
- ***Keratoacanthoma
Premalignant:
- Solar keratosis
- Bowen’s disease
- Erythroplasia of Queyrat
Malignant:
- **SCC
- **Basal cell carcinoma
- Epidermal-Dermal region (Melanocytic lesion)
- Benign pigmented naevi
- **Malignant melanoma (*lethal) - Dermis
- Pyogenic granuloma
- Histiocytoma
- Keloid
- Secondary carcinomas
- Kaposi’s sarcoma - Skin appendages
- **Epidermoid (sebaceous) cyst
- **Dermoid cyst
- Pilonidal sinus
- Benign appendage tumour - Hypodermis / Deeper tissues
- Lipoma
- Liposarcoma
- **Neurofibroma + Sarcoma
- **Neurofibromatosis
- Schwannoma
- Deeper lesions e.g. ganglion - Vascular origin
- Campbell de Morgan spots (aka Cherry angioma, Senile haemangioma)
- Spider naevi
- Angioma
- Glomus tumour of digits
Verruca vulgaris (Common warts) (+ SpC Revision)
- Multiple papular skin-coloured lesions
- Irregular thickened keratinised (warty) top
- Caused by ***HPV
- Related to trauma, on hand / foot
- Contagious + often multiple
- Poor immunity —> Multiple viral warts
- Brown / gray with a rough surface (***Warty spikes)
- Plantar warts: **Flattened + **Painful
- Genital warts: Soft + **Fleshy (*Condylomata acuminata)
- Can recur after treatment
Treatment:
1. Heat cautery
2. Cryosurgery / Cryotherapy
3. Laser (CO2)
4. Surgery (for persistent / recurrent cases)
Corn + Callouses
- Massive thickening of ***stratum corneum
- Due to chronic trauma / irritation
- Corn: ***smaller, well marginated, square-shouldered
- Callouses: ***larger, more diffused, slope-shouldered
- Management: removal of irritation, paring, keratolytic agent (10-20% ***salicylic acid)
Common cystic lesions (+ SpC Revision)
- Epidermoid cyst (Sebaceous cyst)
- true cyst (epithelial lining)
- ?hair follicle origin
- spherical, **attached to skin (always **mobile), overlying **punctum
- contains cheesy **keratin material **NOT sebum
- may get **infected (red, swollen, tender)
- multiple: consider ***Gardner’s syndrome (associated with osteoma, fibromas, intestinal fibromatoses, lipomas, leiomyomas, polyposis coli)
- complications: infection, sebaceous horn (sebaceous content keep forming without being removed then dried up)
- management: Excision - Implantation dermoid
- epidermal fragment (by penetrating injury) driven into dermis
- lined by **epidermis producing keratin material
- contains white amorphous material
- tensely cystic (continuous proliferation of epithelium)
- history of **trauma + presence of scar
- common sites on fingers
- management: Excision (to avoid infection) - Other epidermoid cysts:
Milia
- small 1-2mm epidermoid cysts on ***face
Pilar cyst
- trichilemmal cyst / wen
- ***slow-growing firm cyst on the scalp
Steatocystoma multiplex
- true sebaceous cyst —> contains ***sebum
-
**Dermoid cyst (sequestration dermoid)
- **congenital cystic lesions growing slowly
- occurs at ***embryonic fusion line regions (e.g. midline of scalp, external angle of eye, lower mandible)
- contains keratin, hair, sebaceous glands etc.
- management: excision
Keratotic lesions (+ SpC Revision)
- Seborrhoeic keratosis (Basal cell papilloma / Seborrhoeic wart / Senile wart)
- common in **elderly
- **brownish-black, raised, well-marginated
- **plaque-like papules, “stuck-on”, square-shouldered
- feels **waxy + irregular
- proliferation of ***basal cells of epidermis
- face, neck, chest wall
- management: observe, cryotherapy, curettage, shaving, excision - Actinic keratosis (Solar keratosis, Senile keratosis)
- **sun-damaged skin by UV, in exposed parts
- dry, scaly, crusty top, erythematous based
- early lesions: flat, roughened / scaly papules (which could just be palpable)
- hyperkeratosis + acanthosis (i.e. thickening of skin) —> **pre-malignant
- excision
- if multiple: excision, curettage, cryosurgery, 5FU creams - Keratoacanthoma (Molluscum sebaceum)
- from squamous cell of hair follicles
- same area as BCC
- can be **indistinguishable from BCC
- **dome / nodular-shaped, flesh-coloured
- **central crater filled with **keratin plug (Look like tumour central ulceration)
- natural history: **rapid growth for a few weeks —> static for a few months —> **involution spontaneously, leaving an ugly scar
- ***?variant of SCC
- management: excisional biopsy, ?observation, ?RT
Naevi
Developmental abnormalities: Hyperplasia of incompletely differentiated tissue elements
Types:
1. Melanocytic naevus (Mole)
2. Strawberry naevus (Infantile haemangioma)
3. Sebaceous naevus (Naevus of Jadassohn)
- Melanocytic naevus (Mole)
- Very common, benign
- Depends on location of naevus cells:
1. Junctional (child, flat, darkly pigmented)
2. Compound (younger adult, raised, variable pigmentation)
3. Intradermal (older adult, dome-shaped, deep seated, lighter / flesh-coloured)
4. Congenital (giant / hairy) (big, hairy, dark, raised, thick (**risk of malignant change))
5. **Dysplastic - uncommon in Asians, usually multiple, occasionally solitary
- irregular border + speckled pigmentations
- 2 major groups:
—> Sporadic: Caucasians, fair skin, poorly tanned, excessive sunlight exposure with freckles etc.
—> Familal: Dysplastic naevus syndrome, run in families, uncommon, up to 400x lifetime risk of malignant change
6. Others (blue, Spitz, halo etc) - risk of malignant changes very small except:
—> Dysplastic naevus (esp. with family / personal history)
—> Giant congenital melanocytic naevus (“bathing trunk”, life-long surveillance)
—> >50, >2mm size - DDx: **Melanoma, **BCC, ***Seborrhoeic keratosis
- when in doubt —> Excisional / Incisional biopsy
Dermatofibroma (Histiocytoma, Sclerosing angioma)
- Firm skin nodule, 0.5-3 cm
- Fibrosis + Vascularity + Fe pigmentation
- Benign
- ***History of trauma / insect bite
- Deep reddish-brown
- ?Histiocytic origin
- DDx: ***Dermatofibrosarcoma protuberans (malignant)
Dermatofibrosarcoma protuberans (DFSP)
- **locally aggressive
- painless, indurated plaque with irregular nodules
- skin-coloured, border not well defined
- ?fibroblastic origin, ?malignant variant of DF
- infiltrative histologically with cords / nests of cells invading into adjacent soft tissue
- prone to **local recurrence, **seldom metastasise
- management: **wide excisional margin +/- RT
Neurofibroma
From supporting ***fibroblasts of peripheral nerves
(- Neurilemmoma = Schwannoma (from neurilemmal cells, encapsulated, lobulated firm tumour))
- Solitary:
- SC, **tender, **firm nodule, ***mobile laterally - Multiple:
- sessile / pedunculated, skin-coloured / brownish, well-circumscribed
Neurofibromatosis
- AD inheritance
- NF-1, NF-2 (depending on clinical features, genes)
- Multiple lesions of different sizes, ***cafe au lait pigmentations
- ***Acoustic neuroma (type 2)
- deformities / disfigurement
-
**possible malignant change
(- **Plexiform NF: skin thickened with foldings, myxfibromatous degeneration, sporadic / familial)
Lipoma (+ SpC Revision)
- commonest SC benign condition
- **SC lump / mass (1-20cm) —> **Can pinch skin over lipoma
- **Soft, **smooth surface with ***lobulations + encapsulated
- Diffuse / Well-defined lobulated mass
- Diffuse: ***Madelung’s disease (extensive + big lipoma in nape of neck, upper back in chronic drinkers)
- ***matured fat cells in thin fibrous capsule, grouped into lobules by vascular connective tissue septal
- big lipoma: may be ***soft + fluctuant
- management: conservative, excision, liposuction
- potential malignant change: ***Painful, Rapidly enlarging, Skin changes, Firm consistency may indicate malignancy (sarcomatous changes)
Vascular anomaly
- Vascular tumours
- Rapid proliferating vascular endothelium
- usually **not present at birth
- rapidly ↑ in size
- may involute
- F:M = 3:1
- 60% head and neck
- **most common tumour of infancy
- “strawberry naevus” (NOT a naevus but vascular tumour)
Types:
- Benign
- Locally aggressive / Borderline
- Malignant
- Vascular malformations
- Congenital abnormal vascular anatomy + morphology
- **present at birth (but may not be clinically apparent)
- **grow in proportion to body size
- can degenerate but also can hypertrophy (AVM)
- ***Fast flow (e.g. Arterial) vs Slow flow
- diagnosis by history + P/E
- adjuncts: USG, MRI, Angiography
Types:
- Simple (Capillary / Lymphatic / Venous / ***Arteriovenous / Arteriovenous fistula)
- Combined
Infantile hemangioma (Strawberry naevus)
- NOT Congenital haemangioma!
- Bright red haemangioma, in baby
- appears shortly after birth —> rapidly grows for a few weeks to months —> static for some time —> involution
- residual redundant skin / scar common
Management:
1. Observation
2. **Steroid, **β-blocker
3. Laser, Excision
S/S of Vascular tumours
Intrinsic:
- **Bleeding
- **Ulceration
- ***Kasabach-Merritt syndrome (Thrombocytopenia associated with kaposiform, haemangioendothelioma NOT common Haemangioma)
Extrinsic:
- Upper eyelids
—> deprivation **amblyopia (弱視) + failure to develop binocular vision
—> corneal distortion + astigmatism
- **Airway obstruction (if grow in airway)
Vascular malformations
- Arterial: Fast flow e.g. AVM
- **Schobinger staging of AVM
Stage 1: A blue-skin blush
Stage 2: A mass associated with a bruit + a thrill
Stage 3: A mass associated with ulceration, bleeding, pain
Stage 4: Stage 3 lesions decompensation producing heart failure
- Management: Pre-op **embolisation +/- Complete excision - Venous
- Slow flow
- Management: Debulking, ***Sclerotherapy - Capillary
- e.g. ***Port-wine stain (on face)
- Management: Laser - Lymphatic
- Macrocytic vs Microcytic
- e.g. primary **lymphedema, **cystic hygroma - Combination
- e.g. Klippel Trenaunay Syndrome, Parkes Weber syndrome
Port-wine stain
- Capillary malformation
- Present at birth, often on ***face / scalp
- Flat / slightly elevated, ***reddish-blue to purplish
- Advancing age —> thicker + nodular + hypertrophy
- Associated with intracranial haemangioma —> DDx: ***Sturge-Weber syndrome
Cystic hygroma
- Collection of ***lymphatic sacs containing lymph
- Failure of fusion of lymphatic channels
- Present at birth (some later)
- Usually root of neck, axilla, groin
- **Soft, fluctuant, markedly **transilluminating
- Management: Excision
Skin tags (Papilloma)
- More in advanced age
- Benign
- Proliferation of epidermis
- Often multiple, 1-5 mm
- Loose CT core with normal covering ***squamous epithelium (pigmented / keratinised)
- Management: Excision, Laser
Cutaneous horns
Descriptive term for any protuberant horny skin growth
- usually conical projection of ***keratinised material
Pathologically may be pre-malignant / benign / malignant:
1. **Actinic keratosis (with / without underlying SCC) (pre-malignant)
2. **Seborrhoeic keratosis (benign)
3. ***SCC (malignant)
Management:
- Biopsy to confirm Dx + remove the horn
Pyogenic granuloma
- Benign condition
- aka “Eruptive Haemangioma”
- Induced by ***trauma
- ***Red, fleshy, spherical nodule —> looks like a vascular tumour
- **Rapid + excessive growth of granulation tissue rich in **blood vessels + inflammatory cells
- **Ulcerate + **Bleed easily —> complaining of bleeding
- Management: Excision, Curettage, Diathermy of base
Xanthelasma
- Deposition of ***lipid-laden macrophages in the superficial dermis
- Soft, flat-topped yellow papules, may coalesce
- Usually starts at upper eyelid near the medial canthus
- About 1/3 of patients have hyperlipoproteinaemia
- Management: Excision (may recur)
Benign tumours of Epidermal appendages
- Hair follicle
- Trichofolliculoma
- Trichoepithelioma
- Pilomatrixoma
- Trichilemmoma - Sebaceous gland
- Sebaceous adenoma
- Adenoma - Sweat gland
- Cylindroma
- Synringoma
Some have typical appearance, otherwise Dx confirmed on ***Histological exam
Pre-malignant skin conditions
- **Bowen’s disease, **Paget’s disease of nipple
- ***Xeroderma pigmentosa, Albinism
- Chronic unstable scar / Destruction of skin
- Chronic radiation dermatitis
- Burn scar / Chronic osteomyelitis
- ***Actinic keratosis
Bowen’s disease (***Squamous carcinoma-in-situ, Intraepidermal epithelioma)
Paget’s disease of nipple
Bowen’s disease (**Squamous carcinoma-in-situ, Intraepidermal epithelioma)
- Dysplastic cells confined to basal lamina (without definite invasion)
- Thickened, reddish-brown, scaly patch with irregular border
- If in penis: **Erythroplasia of Queyrat with velvety-red plaque like appearance
- Management: Excision, **RT, **Topical 5FU, Cryotherapy, Photodynamic therapy
Paget’s disease of nipple:
- Paget cells arise from **mammary ducts to the nipple epidermis
- **Erythema + ***Eczematous lesion of nipple —> Erosion + Ulceration
- 50-60 yo
- 97% has underlying breast carcinoma, ~50% present with breast mass
- Diagnosis: Incisional biopsy
- Management: Treat underlying CA breast
Extramammary Paget’s disease (EMPD)
- ***Peno-scrotal area / Axilla area
- Intraepithelial adenocarcinoma
- Associated with underlying malignancy e.g. Prostate, Colon —> Need to screen
- Management: Wide excision + Treat underlying malignancy if any
Common malignant skin cancers
Most common —> less common:
1. Basal cell carcinoma (BCC)
2. SCC
3. Malignant melanoma
- Basal cell carcinoma (BCC) (+ SpC Revision)
- Due to ***excessive sunlight (UV) exposure
- ***Commonest skin cancer
- ***Low grade malignancy
- ***Middle age / Elderly
- Originate from ***basal epidermal cells (?pilosebaceous unit), slow growing
- **Face / scalp / **neck / dorsum of hands / forearms
- Also in patients: XP (xeroderma pigmentosum), ALB (albinism), Naevoid basal cell carcinoma syndrome, Sebaceous naevus (congenital lesion predisposing patients to BCC)
- Multiple lesions are common
- **Locally invasive, **slow growth, ***seldom metastasise
- ***Serous discharge / bleeding, may be pigmented
Clinical types:
1. ***Pigmented (common in orientals)
2. Nodular / Nodular-ulcerative
3. Superficial
4. Cystic
5. Morphreaform (sclerosing)
Features:
- Typical ulcer: **Rolled edge + “cystic lesion” with **pearly white edge + ***telangiectasia + central ulceration (Rodent ulcer)
- Seldom spread to regional LN / by blood
- Most lesions are well localised
Management:
1. Excision with margins (2-3 mm) (**3-5 mm (SpC Revision)), **RT, 5FU cream
2. Cryotherapy, cauterisation, electro-desiccation should be used with ***much caution
Beware of lesions: Post-op / RT recurrence
- Medial canthus (眼角)
- Peri-alar
- Preauricular
- Morpheaform type (∴ need a wider excision margin)-
- Squamous cell carcinoma (SCC) (+ SpC Revision)
- Mostly a result of ***excessive sunlight (UV) exposure
- Less common but **more malignant than BCC + **more rapid growth
- Arise de novo / in pre-existing skin lesion
- May develop from ***Actinic keratosis
- Other causes: Carcinogens (RT, **arsenic, chromium compounds, soot, tar), Chronic **non-healing wounds, Unstable scars
- Congenital diseases: XP, ALB
- Immunosuppression: Diseases, Therapy
Clinical features:
- **Everted edge / Exophytic growth
- **Irregular ulcer (e.g. **Marjolin’s ulcer: malignant ulcer that develop over chronic wound, usually in sacrum / venous ulcer in ankle)
- **Indurated base + fixed to underlying structure
- Evidence of sun-damage skin lesions
- **More aggressive: metastasis by **lymphatic (examine LN) + ***haematogenous route
Investigation:
- Biopsy from ***edge of ulcer
Management:
- Wide excision (10-15mm from Goddisk) +/- Reconstruction (∵ **larger excision margin)
- **Block dissection for LN metastasis (e.g. axillary dissection)
- RT
- Malignant melanoma (+ SpC Revision)
- Malignant tumour of ***melanocytes (mesodermal) (normally located in basal layer of epidermis)
- Cutaneous ones induced by ***sunlight (UV)
- Arise de novo / from pigmented nevus
- Less common than BCC, SCC
- Other sites: mucous lining, **choroid of eye, meninges, soft tissues (*amelanotic melanoma: no melanin production —> skin colour / erythematous colour
Signs of malignancy in benign nevus:
1. Increase in size
2. Increase / Decrease in pigmentation
3. Ulcerate, weep, bleed
4. Itchy / burning sensation
5. Spread of pigmentation
6. LN enlargement
- Any suspicion —> Biopsy
(From CFB14: Mnemonic (ABCDE):
- Asymmetry: Irregular shape
- **Border: Ragged outline
- Colour: Variation
- Diameter: >6mm across / recent increase in size
- **Elevation: Raised above surface of skin
- Evolution: changes in size, colour, shape over time)
Features:
- **Aggressive: metastasis to **LN (Satellite / In-transit lesions; Regional / Distant LNs) / by **blood
- Most are **darkly pigmented lesions
- Recent onset / change in pigmentation of pre-existing lesion, irregular border / appearance
- Increase in size, bleeding, loss of hair
5 Clinical types:
1. Superficial spreading
2. **Nodular (most aggressive, invade deep in SC tissue early)
3. **Lentigo maligna melanoma (least aggressive, face, nailbed)
4. Acral lentiginous melanoma (hand / foot)
5. Subungal melanoma (nail)
Grading system:
1. **Breslow scale (thickness) (more favoured for less observer’s variability)
2. **Clark’s level of invasion (level 1-5)
—> guide treatment + prognosis
—> both correlate with LN metastasis + survival
—> Thinner lesions —> Better prognosis
Management:
1. Surgery
- Only treatment method for potential cure
- Excision margin: depends on ***Breslow’s thickness (i.e. depth of invasion), range from 1-3 cm
- SLNB
- For intermediate thickness tumour (e.g. 1-3 mm) —> carries **prognostic information + facilitate **staging - Regional LN dissection
- Improves nodal control but ***NOT survival - Block dissection
- For LN metastasis if no distant metastasis
(- ?Role of elective block dissection in intermediate thickness tumour) - Others
- Hyperthermia + Isolated limb perfusion for in-transit metastasis in specialised centre
- Systemic chemotherapy ***not useful
- Immunotherapy (control lesion + prolong survival): Anti-PD1 (Pembrolizumab, Nivolumab) (SpC PP)
Uncommon malignant tumours
- Merkel cell carcinoma
- Skin appendageal carcinoma
- ***Sarcoma
- Malignant nerve sheath tumour
- Angiosarcoma
- ***Lymphoma
- ***Metastatic tumour
If not sure —> biopsy
Benign skin tumours vs Malignant skin tumours
Benign skin tumours:
- In young patients except Melanoma, Sarcoma
Features:
- Remain static in size / grow in proportion with patients
- **Do NOT ulcerate / bleed
- **Well defined regular border
- Can be raised / flat
- No enlarged regional LN
Malignant skin tumours:
- More common in elderly
- **Grow in size
- **Arise from pre-existing lesions e.g. naevus, scar
- **Ulcerate / Bleed
- **Irregular / poorly defined border
- **Raised
- Enlarged regional LN
- **Satellite lesions (e.g. malignant melanoma)
Ambulatory Surgery: Skin lesions (SpC FM)
Keratosis = Growth of keratin on the skin or on mucous membranes stemming from ***keratinocytes, the prominent cell type in the epidermis (wiki)
Seborrhoeic keratosis (Senile wart):
- Benign
- Old age
- Pigmented, dry keratin (dead cell from the top layer of epithelium)
- Rough surface
- Raised
- Does not bleed when cut open
Actinic / Solar / Senile keratosis:
- Premalignant (SCC)
- Sun exposed
- Does not bleed when cut
- More living cells from deeper layers of epithelium
Dermoid cyst:
- Congenital: lateral eyebrow
- Usually in midline??
- Looks like lipoma
- Acquired: on hand due to trauma
Sebaceous cyst (Epidermoid cyst):
- From dermis layer, not able to pinch skin???
- Smooth not pedunculated
- Half have punctum
- Tense consistency
Papilloma (aka Skin tag):
- Prominent, round +/- pedunculated
- If small, equivalent to skin tag
- Fleshy, skin coloured
- Living cells when cut, will bleed
Neurofibroma:
- Buttonhole sign
- Tender, firm nodule, mobile laterally
Dermatofibroma:
- Buttonhole sign
Mole / Nevus:
-Canberaised
- DDx: Melanoma, Seborrhoeic keratosis, BCC
Mucus retention cyst (SpC Revision)
- Obstruction of an excretory duct leading to back pressure of mucus + formation of an epithelium lined cyst
- Minor trauma leading to rupture + escape of mucus into tissue —> recur afterwards
- Smooth, transparent lesion
Choice of anaesthesia
Indications:
- Biopsy / Examination / Surgery
Local anaesthesia:
- Small lesions
- Superficial lesions
- Single lesion
- Cooperative patients
- Prolonged operation / Complicated procedure
Lignocaine (1% / 2% / +/- Adrenaline):
- Max dose:
—> Without adrenaline: 4 mg/kg
—> With adrenaline: 7 mg/kg
- Duration of action: ~1.5 hours —> May give additional dose
1% Lignocaine = 10 mg/ml
Example:
60kg patient:
- 1% lignocaine: 4 x 60 / 10 = 24 ml
- 1% lignocaine with adrenaline: 7 x 60 / 10 = 42 ml
Systemic toxicities:
CNS:
Early:
- Tinnitus
- Blurred vision
- Dizziness
- Tongue parasthesia
- Perioral numbness
Late:
- Slurred speech
- Drowsiness
- Seizure
- Respiratory arrest
CVS:
- Sinus bradycardia (prolonged PR, widened QRS)
- Ventricular arrhythmia
- Hypotension
- Cardiac arrest
Avoid systemic toxicities:
- Proper injection: Avoid IV injection
- Proper dosage
Treatment of systemic toxicities:
- Stop LA injection
- Call for help
- Airway
- **Control seizure by BDZ
- Treat hypotension / bradycardia (CPR if pulseless)
- **20% lipid emulsion bolus (1.5 ml/kg) then infusion (0.25 ml/kg/min): Max dose: 12 ml/kg
