Dermatology: Skin Cancer Flashcards
DECK DIRECTLY COPIED FROM CANCER CARE
State the skin cancers you need to know
- Melanoma
- Basal cell carcinoma
- Squamous cell carcinoma
What cells do basal cell carcinomas arise from?
Slow-growing, locally invasive epidermal skin tumour arising from the stratum basale (used to think originated from basal cell but recently discovered you can get it anywhere other than lip therefore has hair follicle origin)
***The lowest layer of the epidermis is called the basal layer. It contains rounder cells called basal cells.
State some risk factors for BCC
- Fitzpatrick skin types I & II
- UV exposure
- Increasing age
- Smoking
- Immunosuppression
- Male
State the 5 types of BCC; including which subtypes are low risk and which are high risk
Highlight the most common subtype?
Risk depends on many factors but generally nodular and superficial considered less risky
- Nodular (nBCC)
- Superficial (sBCC)
- Morpheic/sclerosing
- Basosquamous
- Pigmented
Order the following skin cancers from most common to least common:
- BCC
- Melanoma
- SCC
- BCC (80%)
- SCC
- Melanoma
If someone has multiple BCCs presenting at a young age, what autosomal dominant condition might this be?
Basal cell naevus (Gorlin) syndrome
Describe the typical presentation of of nodular basal cell carcinoma
- Pearly (shiny) nodule with telangiectasia
- Rolled edge
- Tends to ulcerate with time
- Common on head & neck region
Describe the typical presentation of superficial basal cell carcinoma
- Erythematous irregular patch or plaque
- Slightly scaly
- Usually on trunk
Describe the typical presentation of morpheic/sclerosing basal cell carcinoma
- Shiny, scar-like plaque
- Ill-defined border
- Usually found in mid-facial sites
Basosquamous carcinoma is rare; what is it?
- Mixed basal cell carcinoma (BCC) and squamous cell carcinoma (SCC)
- Infiltrative growth pattern
- Potentially more aggressive than other forms of BCC
Discuss the 2WW referral criteria for BCC
- Only consider urgent referral (2WW) if has skin lesion suggestive of BCC AND there’s concern that a delay may have unfavourable impact due to location or size of lesion
- In others, arrange a routine referral
Discuss what investigations are done for BCC
Diagnosis usually made clinically, biopsy only indicated if clinical doubt exists or when histological subtype may influence treatment & prognosis
Discuss the management of BCC (highlight the most common management/treatment of choice)
- Surgical excision with histological assessment of the margins (target excision depends on subtype)
- Moh’s surgery (for high risk facial BCCs)
- Destructive surgical techniques (small nodular or superficial)
- Curettage (scrape)
- Cryosurgery (extreme cold)
- Radiotherapy
- Destructive non-surgical techniques
- Topical imiquimod (sBCCs)
- Topical fluorouracil (sBCCs)
- Photodynamic therapy (sBCCs)
And of course skin protection advice (cover up, sun cream etc…)
Discuss the prognosis of BCC
- Very good prognosis (85-90% don’t get recurrence)
- Almost never a danger to life
What cells do squamous cell carcinoma arise from?
Cutaneous carcinoma arising from keratinocytes of the epidermis or it’s appendages
State some risk factors for squamous cell carcinoma
- Fitzpatrick skin types (I & II)
- Chronic UV radiation
- Smoking
- Immunosuppression
- Increasing age
- Male
- Genetic conditions (e.g. xeroderma pigmentosum, albinism)
- Chronic inflammation or chronic wounds (e.g. long standing leg ulcers [Marjolin’s ulcer])
- HPV (for genital or anal SCC)
- Actinic keratosis
- Bowen disease
What is actinic keratosis?
- Common premalignant skin condition that arises due to chronic sun exposure
- Presentation:
- Small, crusty or scaly lesions
- May be pink, red, brown or same colour as skin
- On sun exposed areas (e.g. face)
- May have multiple lesions
AK is an epidermal lesion characterized by aggregates of atypical, pleomorphic keratinocytes at the basal layer that may extend upwards to involve the granular and cornified layers. This presentation may resemble Bowen disease or carcinoma in situ, and the distinction between the two is a matter of degree (extent of the lesion) rather than differences in individual cells.**
What is Bowen disease/SCC in situ?
- Squamous cell carcinoma that is confined to the epidermis (with basement membrane intact)
- Presentation:
- Red or pink patch or plaque
- Scaly or crusty
- Might be intermittently itchy
- Common in sun-exposed areas
Describe typical presentation of SCC
- Indurating (hard) keratinising or crusted plaque or nodule
- Commonly in sun exposed sites (e.g. face, forearms, dorsum of hands)
- Often symptomatic:
- Pain
- Discomfort
- Bleeding
- Ulcerating
- Sensory changes
*NOTE: SCCs have different morphologies:
- Well differentiated: scaly and grows slowly
- Poorly differentiated: non-scaly, appear rlike granulation tissue
Discuss the 2WW referral criteria for SCC
Refer via 2WW if person has lesion suspicious of SCC
What investigations are done for SCC?
Biopsy
(helps differentiate e.g. Bowen disease, SCC etc… In SCC would see keratinocyte atypia that invades basement membrane and invasion into dermis. In Bowen disease would see keratinocyte atypia confined to epidermis with intact basement membrane)
For high risk SCCs may consider additional investigations to look for metastases e.g. CT TAP, MRI, PET scan etc…
Discuss the management of SCC
Treatment depends on whether SCC is classified as low risk or high risk (based on clinical & histological features):
-
Most are treated with surgical excision
- 4mm margin if low risk or <20mm lesion
- 6mm margin if high risk or >20mm lesion
- Moh’s surgery may be used in high risk SCC’s and in cosmetically important sites
- Radiotherapy if non-resectable
And of course skin protection advice (cover up, sun cream etc…)
Discuss the prognosis of SCC
State some good and some poor prognostic factors
Prognosis generally very good
What is Moh’s surgery?
Staged resection in which thin layers of skin are progressively removed. Once removed the layers are examined under a microscope. Keep removing layers until only cancer free tissue remains. Usually done under LA.(This differs from surgical excision in which they excise the lesion with a set margin e.g. 4mm or 6mm)
Discuss the management of actinic keratosis and Bowen disease
Options include:
- Moisturisers and sun protection
- Topical treatments (e.g. 5-flurouracil for 4 weeks, imiquimod, diclofenac)
- Cryotherapy
- Curettage & cautery
- Photodynamic therapy
- Actinic keratosis may just be observed if indicated
- *5-FU can make skin red & inflamed hence sometimes topical hydrocortisone is given following 5-FU treatment*
- **Topical therapy & cryosurgery first line for most*
- ***Photodynamic therapy (PDT) is a technique for treating skin cancers and sundamaged skin which might one day turn cancerous (pre-cancers). In PDT a special light activates a cream which has been applied to the lesion (affected area of skin). This treatment kills the abnormal cells in the skin.*
Compare:
- Actinic keratosis
- Bowen’s disease
- SCC
- AK: atypical keratinocytes that appear to crowd the basal layer and lower levels of the epidermis, but do not extend to full thickness
- Bowen’s: full-thickness atypia that is confined to the epidermis, with an intact basement membrane
- SCC: Extend beyond the basement membrane, penetrate into the dermis, and may invade deeper structures
Compare:
- Actinic keratosis
- Bowen’s disease
- SCC
- AK: atypical keratinocytes that appear to crowd the basal layer and lower levels of the epidermis, but do not extend to full thickness
- Bowen’s: full-thickness atypia that is confined to the epidermis, with an intact basement membrane
- SCC: Extend beyond the basement membrane, penetrate into the dermis, and may invade deeper structures
What cells does melanoma arise from?
Malignant tumour arising from melanocytes (found in basal layer of epidermis)
What’s the median age of diagnosis for melanoma?
61yrs
State some risk factors for melanoma
- UV radiation (increased exposure, previous sunburn)
- Fitzpatrick skin types (I-III)
- FH
- Personal history or melanoma
- Having multiple pigmented naevi
- Giant congenital melanocytic vaevus
State the 4 subtypes of melanoma and state whether each is predominantly radial growing or predominantly vertical growing
Predominantly radial growing
- Superficial spreading melanoma
- Acral lentiginous melanoma
- Lentigo maligna melanoma
Predominantly vertical growing
- Nodular melanoma
Describe the typical presentation of lentigo maligna melanoma
-
Hyperpigmented patch or plaque (mole) growing radially following ABCDE rules
- Asymmetry, irregular border, multi-coloured, diameter >0.6cm, evolution
- Occurs in sun exposed regions
- Older/elderly people
Describe the typical presentation of acral lentiginous melanoma
- Affects nails, palms or soles
- Hutchinson sign (extension of pigment into nailfold)
- More common in Afro-Caribbean & asian people
Describe the typical presentation of superficial spreading melanoma
-
Hyperpigmented patch or plaque (mole) growing radially following ABCDE rules:
- Asymmetry, irregular border, multi-coloured, diameter >0.6cm, evolution
- Commonly on arms, legs, back and & chest
- Can occur in young people
Describe the typical presentation of nodular melanoma
- Hyperpigmented or blue/black or amelanotic firm papule, nodule or plaque
- May bleed or ooze
- Occurs in sun exposed sites
- Middle-aged people
What ‘rule’ do predominantly radial growing melanomas follow?
ABDE rules
- Asymmetry
- Irregular border (1. pattern in which lesions extends out in surrounding skin e.g. can you draw nice smooth line around it or is it wiggly? 2. Definition of the border- is the border distinct or are there areas where it merges/fades into surrounding skin? Poorly defined more likely to be aggressive malignancy)
- Multi-coloured (difference between different colours and different degrees of pigmentation)
- Diameter >0.6cm
- Evolution (of all of the above)
What ‘rule’ do predominantly vertical growing melanomas follow?
EFG rules:
- Elevation
- Firm
- Growing
Order the melanoma subtypes most common to least common
- Superficial spreading melanoma (70%)
- Nodular melanoma
- Lentigo maligna melanoma
- Acral lentiginous
Which melanoma subtype is most common?
- Most common= superficial spreading melanoma
- Second most common= nodular melanoma
Discuss the 2WW referral criteria for melanoma
Refer via 2WW if person has:
- Suspicious pigmented skin lesion that has a weighted seven-point checklist score of three or more (but if strong concern one feature is enough to warrant referral)
- Or dermoscopy suggests malignant melanoma of the skin
Consider referral via 2WW if person has:
- A pigmented or non-pigmented skin lesion that suggests nodular melanoma
What investigations are done for melanoma?
- Excisional biopsy with 2mm margin (GOLD STANDRARD but if not possible can do incisional biopsy)
- Consider sentinel lymph node biopsy
- CT TAP for pts with stage IIIB or IIIC melanoma (imaging is not routinely done for lower stages)
- CT or MRI brain
- Consider PET scan in stage IV melanoma
- LDH for stage IV melanoma
Discuss the management of melanoma
-
Suspicious lesions should have excision biopsy. Once diagnosis confirmed then a second surgery/wide local excision with following margins
- In situ= 5mm
- BT = 1mm= 1cm
- BT >1mm - =2mm= 1-2cm
- BT >2mm - =4mm= 2-3cm
- BT >4mm = 3cm
- Radical lymph node dissection if node metastasis
-
Adjuvant therapy:
- Normally immunotherapy (PD1 inhibitors e.g. Nivolumab)
- Targeted therapies (BRAF inhibitors (50% have BRAF mutation), MEK inhibitors)
- Radiotherapy (not often used. Mostly used for brain)
And of course skin protection advice (cover up, sun cream etc…)
Lecturer said doesn’t respond to chemotherapy
Discuss the prognosis of melanoma (include some of the most important prognostic factors)
The prognosis is highly variable, depending on the stage at diagnosis. The most important prognostic indicators are Breslow’s depth of the tumour and lymph node status.
- In situ/stage 0= 98%
- Stage 1= 90-95%
- Stage II (localised disease)= 45-78%
- Stage III (nodal metastases)= 26-69%
- Stage IV (metastatic)= 3-10%
Which melanoma subtype is most aggressive?
Nodular melanoma (the predominantly vertical growing melanoma subtype)
What checklist is used to determine likelihood of melanoma?
7 point weighted checklist:
**Suspicion is greater for lesions scoring 3 points or more. However, if there are strong concerns about cancer, any one feature is adequate to prompt urgent referral under the 2-week rule.
What is the difference between an excisional, incisional, shave & punch biopsy?
Why is excisional the gold standard for melanoma?
Excisional biopsy= entire tumour removed (along with small margin of normal skin around it). Do in elliptical shape to reduce risk of scarring as can design so that ellipse is in line with parallel with existing skin creases and can ensure edges of skin oppose nicely so can heal via primary intention
Incisional biopsy= part of tumour removed. Used if large lesion or if in sensitive region (e.g. eyelid, lip etc…)
Shave biopsy= samples a portion of the superficial layers of the skin and therefore is minimally invasive
Punch biopsy= a punch biopsy involves removing a small piece of skin using a circular blade called a punch (usually 6mm)
Excisional is gold standard as you are hopefully removing the whole lesion. incisional biopsy can make subsequent histopathological assessment difficult.
State some prognostic factors that are included in biopsy report for melanoma
- Breslow thickness (BT): vertical thickness of melanoma in mm
- Clark level: level of melanoma invasion into the anatomical layers
- Lymphatic/vascular invasion
- Mitotic count
- Perineural infiltration
- Presence of ulceration
NOTE: Breslow thickness is more accurate in predicting prognosis and represents the T part of the TNM staging for melanoma
What staging is used for melanoma?
TNM
(Based on primary tumour Breslow thickness, lymph node involvement & metastases)
How common is melanoma?
5th most common cancer in UK
What 3 factors will be considered during MDT to determine which type of skin biopsy pts should have?
- Clinical suspicion
- Location
- Pt preference/ideas
Lymphoma can present in the skin; discuss the two types of cutaneous lymphoma and how they may present in the skin
Two types cutaneous lymphoma:
- cutaneous T cell lymphoma (CTCL) starts in the T cells of the skin
- cutaneous B cell lymphoma (CBCL) starts in the B cells of the skin
CTCL is the most common type of skin lymphoma. It causes flat red patches on the skin that look like eczema and can be itchy. Several parts of the body can be affected.
CBCL is a more unusual type. People tend to have lumps on their skin in 1 or 2 areas, rather than affecting all of the body.
