Skin Cancer Flashcards
What is more common: non-melanoma, or melanoma skin cancers?
Non-melanoma
What are two common non-melanoma cancers?
Basal cell carcinoma (BCC)
Squamous cell carcinoma (SCC)
What are high cancer rates directly related to?
UV exposure in a genetically susceptible population
Other than UV radiation and genetic susceptibility, what are other potential causes of and associations with skin cancers?
Immunosuppression Some rare genetic disorders Burns scars Chronic ulcers - especially (SCC) Sites previously exposed to x-rays/certain chemicals Large numbers and/or atypical moles Personal and family history
What is the graded progression from which SCCs arise?
Actinic keratosis
SCC in situ
What cells do melanomas arise from?
Melanocytes
What is the association between moles and melanomas?
Don’t necessarily arise from moles > usually de novo
If an adult presents with a new mole, it’s melanoma until proven otherwise
Describe an SCC
Hyperkeratotic patch/nodule - Thickened - Scaly - Red Tender on palpation May bleed easily/ulcerate Skin freely moveable - If tethered, then invaded into dermis, possibly deeper
Which are more common and more dangerous: BCCs or SCCs?
SCCs less common but more dangerous
Why are SCCs more dangerous than BCCs?
Rapid growth rater
- Over weeks-months
Greater potential to metastasise to regional lymph nodes and distant sites
Where are SCCs most commonly found?
Chronically sun-exposed sites
- Hands
- Forearms
- Head
- Neck
Describe SCCs on the lip
Tend to ulcerate rather than become keratin nodules
Risk factor: smoking
Risk of metastatic disease increased
What is the treatment for SCCs?
Surgery
- Complete surgical excision with clear margins
High risks lesions may need extra adjunctive management
Radiotherapy may be used alone if clinically warranted; eg:
- Elderly
- Surgical risks
- Size of defect
What is telangiectasia also called?
Arborisation of vessels
Where do BCCs occur?
Chronically sun-exposed skin
Are BCCs invasive?
Locally invasive
Very rarely metastasise
What is the growth rate of BCCs compared to SCCs?
More indolent
Why are BCCs on the scalp most dangerous?
Easily missed
Very locally invasive > can erode to brain
Patients usually die of infection, like meningitis
What is the histology of nodular BCCs?
Palisading
Basaloid cells with pushing border invading into stroma
Describe nodular BCCs
Peraly nodules
With telangiectasia
Often on head and neck
What is a red flag for nodular BCCs?
Bleeding
How do you confirm whether a lesion is a pigmented nodular BCC or a melanoma?
Microscopically
Describe superficial BCCs
Presents as slowly enlarging plaque
May develop superficial erosion
Red flag: solitary red plaque not responding to topical treatment
How are superficial BCCs histologically characterised?
Superficially budding basaloid cells
Describe infiltrating/morphoeic/sclerosing BCCs
Infiltrative histological pattern
Frequently asymptomatic
Can present as scar-like area of induration
What is the treatment for nodular/infiltrating BCCs?
Surgical excision with clear margins
What is the treatment for superficial BCCs?
Surgical excision
Serial curretage
Topical imiquimod
Photodynamic therapy
Describe solar keratoses
Erythematous scaly lesions on dorsum of hands
Not indurated
Not tender
Very common, increasing frequency with age
How often to solar keratoses progress to SCCs?
Rarely
Where do solar keratoses most commonly occur?
Sun-exposed skin on
- Face
- Scalp
- Forearms
- Dorsum of hands
What are the treatment options for solar keratoses?
Cryotherapy Topical Surgical excision for lesions which are - Resistant to treatment - Suspicious for SCC
Can frozen specimens be examined microscopically?
No
Describe Bowen’s disease
In situ CSS
Full thickness epidermal dysplasia
Non-invasive
Where does Bowen’s disease occur?
Sun exposed areas, in particular, lower limbs
What is the risk of malignant transformation into SCC?
3-5%
What are the symptoms of Bowen’s disease?
Often asymptomatic Can be - Itchy - Painful - Bleed
What are the treatment options for Bowen’s disease?
Topical Surgical excision for lesions which are - Resistant to treatment - Suspicious for SCC - Certain high risk patient groups
What are the possible things a pigmented lesion could be?
Benign naevi
Other brown lesions
Dysplastic naevi
Melanoma
Are all pigmented lesions of melanocytic origin?
No; eg:
- Pigmented BCC
- Pigmented actinic keratosis
- Seborrhoeic keratoses
- Solar lentigines
What is the evolution of naevi?
Pigmented lesions present at birth/shortly after = congenital naevi
- Increased risk of developing into melanoma
Mole pattern develops during childhood = acquired naevi
- Lower risk of developing into melanoma
Fully developed by 20s
Involution in old age
What are benign junctional naevi?
Appear during childhood Located at epidermal side of dermal epidermal junction Macular = slightly raised Uniform in colour Less than <1 cm
What are benign compound naevi?
Cells in dermis and epidermis Papules/nodules Even colour Smooth/cobblestone border Less than 1 cm \+/- hairs
What are benign intradermal naevi?
Cells intradermal Sharply defined Papule/nodule Even colour, but paler than other naevi Smooth surface Later onset
What are freckles?
Sun-induced pigmentation Can occur from childhood Prominent in summer Fade in winter Increase in melanin, not melanocytes
What are lentigines?
Sun-induced pigmented macules Middle-aged people Static with time Mixture of colours On sun-exposed areas Sunburn induced/due to chronic sun exposure
What are seborrhoeic keratoses?
Commoner in older patients Warty, stuck on appearance Can get larger with time Can be pigmented Not melanocytic
What are dysplastic naevi?
Show atypical features clinically and histologically
Not malignant melanoma
More than 5 mm
Atypical pigment net on dermascopy
Smudgy borders
Symmetrical
Independent risk factor for development of melanoma, especially if several
What is the management of dysplastic naevi?
Can’t take them all off because taking off most of skin
Take photos of all of them with dermatascope and monitor every 6 months (with new photos) for rest of their life
What are the risk factors for melanoma?
More than 5 dysplastic naevi More than 100 typical naevi Past history of melanoma Strong family history History of blistering sunburn, especially during childhood Previous non-melanoma skin cancer Type 1 skin Freckling Blue eyes Red hair Immunosuppression
What are the symptoms of melanoma?
Change in size
Change in shape/border
Change in colour
Itch, pain, bleeding
What are the signs of melanoma?
A = asymmetry B = border irregularity C = colour variegation D = diameter >5 mm E = evolution = any changing lesion - Change trumps everything
What are the limitations of classifying melanomas using ABCDE on examination?
Melanomas may have a diameter of <5 mm, especially early in evolution
Some subtypes of melanoma often don’t fulfill criteria
Many benign lesions may satisfy all ABCDE criteria
What are some clues that a skin lesion is a melanoma?
Ugly duckling sign = spot that doesn’t belong with others
New lesion
History of change in naevus
What are some subtypes of melanomas?
Superficial spreading melanoma
Lentigo maligna
Acral lentiginous melanoma
Nodular melanoma
Describe superficial spreading melanomas
80% of all melanomas
Usually follow ABCDE rules
Evolves over weeks-months
Describe lentigo maligna
Gradually enlarging pigmented lesion Usually on face Very slow evolution - May be present for years Progress into lentigo maligna melanoma
Who gets acral lentiginous melanomas?
Any skin type
Occur on palms of hands and soles of feet
Describe nodular melanomas
Often fit E but not ABCD criteria Rapid growth Early invasion Majority amelanotic More common in older males
What extra criteria are added to ABCDE when assessing nodular melanomas?
E = elevation F = firm G = growing
What are some biopsy techniques?
Punch biopsies
Shave biopsies
Excisional biopsies
Which biopsy is best for pigmented lesions and why?
Excisional biopsies, because don’t miss the worst bit of lesion
What is the recommended margin for each of the Breslow thicknesses?
In-situ = 5 mm
Less than 1 mm = 1 cm
1-4 mm = 1-2 cm
More than 4 mm = 2 cm
What does prognosis of melanomas depend on?
Depth of cancer Ulceration Mitotic rate Age Sex Other patient factors Location
What is the follow-up protocol for patients who have had skin cancer?
Regular follow-up Full skin examination to look for - Suspicious lesions - Recurrences of previous lesions - Examine - Lymph nodes - Liver - Spleen Frequency of checks depends on skin cancer and risk factors Need to be told to seek urgent medical opinion if they have any concerns about new/changing skin lesions
