Introduction to Dermoscopy Flashcards
What is Dermoscopy?
Examination of the skin via skin microscopy with 10-14x magnification and a lighting system. Mainly used to evaluate pigmented lesions to distinguish malignant from benign.
In Dermoscopy, the pigmentation of lesions is evaluated by what 9 colours?
Black
Dark Brown
Tan
Grey
Steel Blue
Purple
White
Yellow
Red
How is symmetry described Clinically vs Dermatoscopically?
Clinically, symmetry is described in terms of shape of the lesion e.g. symmetrical vs asymmetrical.
Dermatoscopically, symmetry is described in terms of the pattern e.g. homogenous vs heterogenous colour and structure.
What are 4 types of borders which can be seen on benign and malignant naevi?
Irregular edge is often seen in melanoma, but is quite common in benign lesions too.
Fade out border-often seen in atypical naevi
Sharply demarcated in a small segment (typical of melanoma).
Sharp cut-off all the way around in a regular or irregular pattern.
A ‘moth-eaten’ edge is seen as concave areas at the edge of a lesion.
What is this lesion, and what are the white structures within it?
This lesion is a superficial BCC. Crystalline structures are shiny, bright white, parallel or disordered linear streaks. They are due to excessive collagen and may be seen in dermatofibroma, scar, BCC with fibroplasia, SCC, Spitz naevi and melanoma.
NB: White shiny areas are characterised by similar bright white structures of non-linear shape. Rosettes are four bright white points grouped together like a four-leaved clover, and are typical of actinic keratosis.
Describe the 3 point checklist in Dermoscopy, it’s purpose, and what each of the 3 points are:
The 3 point checklist has a high sensitivity for melanoma. There is a high liklihood of malignancy (melanoma/BCC) if a pigmented lesion has 2 of these criteria. It’s purpose is to inform non-experts on whether to perform a biopsy and thus not miss the detection of melanomas.
1-Asymmetry of colour and structure in one or two perpendicular axes
2-Atypical pigment network with irregular holes and thick lines
3-Blue-white structures: any type of blue or white colour, i.e. combination of blue-white veil and regression structure
Score this naevus based on the 3 point checklist
Reticular pattern-Naevua
Score=0
No asymmetry, no atypical network and no blue/white structures
Score this naevus based on the 3 point check list
Regular globules-Naevus
Score=1
Asymmetry, no atypical network and no blue/white structures
Score this naevus based on thie 3 point checklist:
Score =2
Asymmetry, A_typical network_ with no blue/white structures
Score this naevus based on the 3 point check list:
Score=3
Asymmetry, Atypical network and Blue/white structures
What is this lesion and does it have a typical pigment network?
Junctional Naevus
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Plantar naevus
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Facial Lentigo
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Ephilis/Freckle
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Compound Naevus
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Junctional Naevus
Typical pigment network
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Melanoma
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
a) What is another name for this lesion, where does it most commonly present, describe the growth pattern and at what size does it become concerning?
Lentigo Maligna
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
a) Lentigo maligna is also known as Hutchinson melanotic freckle.
- It occurs in sun damaged skin so is generally found on the face or neck, particularly the nose and cheek.
- Lentigo maligna is an early form of melanoma in which the malignant cells are confined to the tissue of origin, the epidermis, hence it is often reported as ‘in situ’ melanoma.It grows slowly in diameter over 5 to 20 years or longer. Lentigo maligna melanoma is diagnosed when the melanoma cells have invaded into the dermis and deeper layers of skin. Lentigo maligna has a lower rate of transformation to invasive melanoma than the other forms of melanoma in situ (under 5% overall). However, the risk of invasive melanoma is greater in larger lesions, with up to 50% of those with diameter of greater than 4 cm being reported to have an invasive focus.
What is this lesion and does it have a typical pigment network?
Lentigo Maligna
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Melanoma
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Lentigo Maligna
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Lentigo Maligna/Melanoma in situ
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Lentigo Maligna
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Lentigo Maligna
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have a typical pigment network?
Atypical Naevus
Atypical pigment network
Black arrows to broadened network, asterisk to streaming
NB: Not all lesions with atypical network prove to be malignant.
What is this lesion and does it have Blue/White structures?
If so, what does these structures mean?
Dysplastic Naevus
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Lentigo Maligna
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Melanoma
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Blue Naevus
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Congenital Naevus
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Basal Cell Carcinoma
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Dysplastic Naevus
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
What is this lesion and does it have Blue/White structures?
Melanoma
Contains a combination of blue-white veil and regression structures.
NB: The colour can be subtle. Not all lesions with blue-white structures are malignant.
