Revised pattern analysis Flashcards
Primary pattern of lines reticular or branched: Ddx
Melanocytic
B keratinocytic
Primary pattern of lines reticular + asymmetry + clue or exception =
melanoma
One pattern (reticular, curved, structure-less) + one colour brown + abrupt border
Solar lentigo
Melanotic maculates of lip may have …… pattern
Reticular
Melanotic macule of nail matrix and genitalia are expected to have ……. or ……. pattern
lines curved or structureless
SK with asymmetry, grey colour, thick lines reticular, peripheral black dots/ clods, segmental radial lines require ……. for diagnosis of SK
Multiple criteria of SK including multiple orange and white clods, thick curved lines, abrupt border over total periphery.
Peripheral reticular lines combined with paler central structureless +/- white lines is consistent with …
DF
Pattern associated with accessory nipple
Peirpheral reticular lines with central structureless area
Primary pattern of lines angulated: Ddx
Melanocytic
Benign keratinocytic
BCC
One pattern of angulated lines + chaos colour or angulated lines combined asymmetrically with another pattern should be
excised on suspicion of melanoma
Are angulated lines seen in BCC
Rarely
Which benign lesions may have clue of angulated lines
Pigmented AK
SL
SK
Primary pattern of lines radial Ddx
Melanocytic
BCC
SCC
DF
If pseudopods occur together with lines radial then …
Radial lines take priority.
Pseudopods become a clue.
In order for radial lines to constitute a pattern they need to be ..
circumferential
Central structureless brown black or grey or dark clods with pattern of radial lines =
reed nevus or recurrent nevus
Radial lines converging to a central point within lesions is ….
highly specific for BCC
In pigmented SCC radial lines are usually composed of ….
dots in linear arrangement.
Stable symmetrical lesions with pattern of radial lines surrounding structureless pale centre will be ..
dermatofibroma
Primary pattern of lines curved Ddx
Melanocytic
Benign keratinocytic
One pattern, lines curved + one colour, brown can be …
Nevus
SL
SK
> 1 pattern, including lines curved + one colour, brown can be …
Melanoma
Nevus
SL
SK
> 1 pattern, including lines curved, suspect melanoma when ….
other colours of melanin are present.
Curved lines, melanoma expect ….
Dermatoscopic chaos inc chaos of border abruptness
Curved lines, Nevus expect
Gradual border over total periphery. Biological symmetry.
Curved lines, solar lentigo expect ..
flat, uniform abrupt scalloped border.
Curved lines, SK expect
raised + uniformly abrupt border + additional clues to SK
Melanotic macule on lip is likely to be …
one pattern, lines curved, or structureless, small, well circumscribed, may contain some grey colour.
Melanotic macules on the labia are likely to be …
large and poorly circumscribed, mandating biopsy.
Pattern of pseudopods
Melanoma or Reed (Rarely Spitz) nevus
Primary pattern of circles Ddx
Melanocytic
Benign keratinocytic
SCC
DF
Ddx pigmented grey circles head and neck
Melanoma.
Pigmented SCC in situ
Pigmented AK
LPLK
Can nevus have pattern of circles
not expected
Pattern of circles in SK can be caused by …
pigment in follicular epithelium OR
basal hyperpigmentation in presence of acanthosis
Circles in SK are …..
not associated with follicles and are usually distorted
Circles in pigmented SCC may be present and are ….
in a linear arrangement
reticular and curved lines take …… over circles
priority
Pattern of white circles in flat lesion on head or neck is clue to …
AK or
SCC in situ
Pattern of white circles in flat lesion on head or neck combined with grey dots is clue to …
Pigmented AK
or
Pigmented SCC in situ
Pattern of grey dots in p AK and SCC in situ
Distributed symmetrically, or surrounding hair follicles.
Primary pattern of clods Ddx
Melanocytic Benign keratanocytic BCC Angioma Dermatofibroma.
A lesion with one patter, clods, and one colour is assessed according to ….
colour of clods
A lesion with one pattern, clods, and > one colour is assessed according to …
symmetry and specific clues.
Pattern of clods, melanoma …
> 1 colour, dominant pigment melanin, asymmetry of colour, clue to melanoma
OR
combined asymmetrically with dot or structureless pattern + clue
Pattern of brown clods confident predictor of …
nevus likely congenital or Spitz
Pattern of ski coloured clods
congenital nevus or SK
One pattern clods, symmetrical, > 1 colour, dominant pigment is colour of melanin is predicted to be …
nevus, congenital or Spitz
Primary pattern of clods, other pattern limited to dots and structureless expected to be …
congenital spitz or reed nevus
Primary pattern of clods, combined asymmetrically with another pattern, melanin is dominant pigment, > 1 colour present : Ddx
Melanoma.
BCC
SK
One pattern, clods and one colour + orange clods and sharply demarcated border
SK
One pattern, clods which are yellow, white or skin coloured Ddx
SK
Congenital nevus
One pattern, clods distributed asymmetrically, pigmented with colour of melanin, more than one colour, no clues
SK
> 1 pattern, primary pattern clods, asymmetrical, clods yellow or white predicts
SK
One pattern, clods and one colour blue =
BCC
One pattern, clods and one colour orange without sharply demarcated border
BCC, orange clods dt ulceration
> 1 pattern, primary pattern clods, asymmetrical, clods are orange. Ddx
BCC or SK, sorted by specific clues.
Primary pattern of dots ddx
Any of major 5 categories
Pattern of dots sorted on basis of …
colour
Grey dots ddx
LPLK
Pigmented AK
Pigmented Bowen’s
Melanoma
Brown dots ddx
Pigmented bowen’s
Clark nevus
Grey dots + structureless Ddx
LPLK Pigmented Ak Pigmented Bowen's Melanoma BCC
Brown dots + structureless Ddx
Pigmented Bowen’s
Clark nevus
Solar lentigo
Congenital nevus
Blue dots likely
BCC
Black dots ddx
Melanoma is some peripheral
Clark nevus
Structureless pattern, Ddx
Melanocytic Benign keratinocytic BCC SCC DF Other
