Skin Cancer Flashcards
What is melanoma?
- Malignant tumour arising from melanocytes
- > 75% of skin cancer deaths
- Can arise on mucosal surfaces (e.g. oral, conjunctival, vaginal) and within uveal tract of eye
- Rising incidence rates observed worldwide
Which type of skin cancer is this?
Melanoma
What are the risk factors for melanoma?
Genetic factors - Family history (CDKN2A mutations), MC1R variants - DNA repair defects (e.g. xeroderma pigmentosum) - Lightly pigmented skin - Red hair Environmental factors * Sun exposure – intense intermittent or chronic * Sunbeds * Immunosuppression Phenotypic * >100 Melanocytic nevi * Atypical melanocytic nevi
Who is most likely to get melanoma?
Caucasians living with more sun exposure e.g Australians
What are the subtypes of melanoma?
- Superficial spreading
- Nodular
- Lentigo maligna
- Acral lentiginous
- Unclassifiable
What is superficial spreading melanoma?
- Most common type in fair-skin
- Trunk of men
- Legs of women
- Can arise de novo or in pre-existing nevus
- Regression in 2/3 (greyness or hypopigmentation) caused by host immunity against tumor cell
What is this type of melanoma?
Superficial spreading
What is the growth pattern of superficial spreading melanoma?
Horizontal then vertical growth
What is nodular melanoma?
- 2nd most common type of melanoma in fair skinned individuals
- 15-30% of all melanomas
- Most commonly trunk, head and neck
- M>F
- Blue to black, but sometimes pink to red, nodule – may be ulcerated, bleeding
- Develops rapidly
What is the growth pattern of nodular melanoma?
Only vertical growth
What is this type of melanoma?
Nodular melanoma
What is lentigo maligna melanoma?
- 10% (minority) of cutaneous melanomas
- > 60 years old
- Occurs in chronically sun-damaged skin
- Most common on face
- Slow growing, asymmetric brown / black macule with colour variation and an irregular indented border.
- In situ – termed ‘Lentigo Maligna’
- Invasive termed ‘Lentigo Maligna Melanoma’
- 5% of lentigo maligna progresses to invasive melanoma
What is this type of melanoma?
Lentigo maligna
What is acral lentiginous melanoma?
- Relatively uncommon
- Most frequently in 7th decade of life
- Typically palms and soles OR in / around nail apparatus
- Incidence similar across all racial and ethnic groups
- Disproportionate percentage of melanomas diagnosed in Afro-Caribbean (up to 70%) or Asians (up to 45%)
What is this type of melanoma?
Acral letiginous
What is this called?
Melanonychia
What is amelanotic melanoma?
Melanoma where the malignant cells have little to no pigment
What is the acronym for melanoma awareness?
ABCDE
* Asymmetry
* Border irregularity
* Colour variegation
* Diameter greater than 5mm
* Evolving
What is Garbe’s rule?
If a patient is worried about a single skin lesion, do not ignore their suspicion and have a low threshold for performing a biopsy
What are the differential diagnoses for melanoma?
- basal cell carcinoma
- seborrhoeic keratosis
- dermatofibroma
What is this?
Seborrhoeic keratosis
What is this?
Dermatofibroma
What are the poor prognostic features of melanoma?
- Increased Breslow thickness >1mm
- Ulceration
- Age
- Male gender
- Anatomical site – trunk, nhead, neck
- Lymph node involvement
What is Breslow thickness?
Measurment from granular layer to the bottom of the tumour
Which investigations are done for melanoma?
Dermoscopy
What is important to know about dermoscopy?
- can improve correct diagnosis of melanoma by nearly 50%
- should not be considered in isolation
What is the managment for melanoma?
- Primary excision down to subcutaneous fat
- Wide incision
- Sentinel lymphoma node biopsy
- Prevents local recurrence or persistent disease
What is sentinel lymphoma node biopsy?
Biopsy of the sentinel node (inital node of lymphatic drainage for a finite region of skin, most likely node to contain metastses)
What imaging is done for melanoma?
PET-CT
MRI Brain
What is a major prognostic indicator in melanoma?
LDH
What is the managment of unresectable or metastatic melanoma?
- immunotherapy
- mutated oncogene target therapy
What is keratinocyte dysplasia/carcinoma?
Solar induced UV damage
What are the four types of keratinocyte dysplasia/carcinoma?
- acitinic keratoses
- Bowen’s disease
- squamous cell carcinoma
- basal cell carcinoma
What is the most common skin cancer?
Basal cell carcinoma
What are the risk factors for keratinocyte carcinomas?
- UV exposure
- fair skin
- genetic syndromes
- nevus sebaceous
- porokeratosis
- organ transplantation and immunosuppressive drugs
- chronic non healing wounds
- ionising radiation
- occupational chemical exposure (tar, aromatic hydrocarbons)
What are acitinic keratoses?
- Atypical keratinocytes confined to epidermis
- Develop on sun-damaged skin - usually head, neck, upper trunk and extremities
- Macules or papules
- Red or pink
- Usually some scale – may be thick scale
- Distinction from squamous cell carcinoma sometimes difficult – requiring biopsy
- Risk of progression to squamous cell carcinoma
What is this?
Acitinc keratoses
What is Bowen’s disease?
- Squamous cell carcinoma in situ
- Erythematous scaly patch or slightly elevated plaque
- May arise de novo or from pre-existing AK
- May resemble actinic keratoses, psoriasis, chronic eczema
What is squamous cell carcinoma?
Carcinoma which arises within background of sun-damaged skin
What can squamous cell carcinoma look like?
- Erythematous to skin coloured
- Papule
- Plaque-like
- Exophytic
- Hyperkeratotic
- Ulceration
What is this?
Squamous cell carcinoma
What is this?
Squamous cell carcinoma
What is keratocanthoma?
- rapidly growing papule with keratotic core
- resolves slowly over months
- mostly occur on sun exposed areas
- difficult to distinguish from squamous cell carcinoma
What is this?
Keratocanthoma
What investigations are done for squamous cell carcinoma?
- diagnostic biopsy
- ultrasound of regional lymphnodes
What are the differential diagnoses for squamous cell carcinoma?
- basal cell carcinoma
- viral wart
- merkel cell carcinoma
What is the treatment for squamous cell carcinoma?
Excision
What is the treatment for squamous cell carcinoma that is unresectable and has high risk features?
Radiotherapy
What is the treatment for metastatic squamous cell carcinoma?
Cemiplimab
What is secondary prevention for squamous cell carcinoma?
- Skin monitoring advice
- Sun protection advice
What are the main subtypes of basal cell carcinoma?
- Nodular
- Superficial
- Morpheic
- Infiltrative
- Basisquamous
- Micronodular
What is the most common subtype of basal cell carcinoma?
Nodular
What is the treatment of basal cell carcinoma?
- Standard surgical excision
- Mohs micrographic surgery
What is merkel cell carcinoma?
- highly anaplastic cells which share features with neuroectodermally derived cells, not actually from merkel cells
- 80% are associated with polyomavirus
- Aggressive, malignant behaviour
- > 40% develop advanced disease
What is this?
Merkel cell carcinoma
