Nail lesions Flashcards
Longitudinal nail pigmentation - AKA ….
melanonychia striata longitudinalis
melanonychia striata longitudinalis definition
pigmentation along nail plate in band-like fashion
melanonychia striata longitudinalis is symmetrical because …
pigmentation of nail matrix produced pigmentation along nail plate with band like fashion - the lesion is symmetrical because of growth of the nail plate
Does symmetrical lesion r/o melanoma
No
Importance of early diagnosis on fingers and toes -
Can offer conservative treatment
melanonychia striata longitudinalis benign causes
ethnic type pigmentation subungual hemorrhage letiginosis - Laugier Hutziker disease drug induced - AZT + anti-TB drugs onychomycosis - very rare cause trauma induced pigmentation - common melanocytic nevus onychomatricoma
melanonychia striata longitudinalis malignant causes
SCC in situ - Bowen’s disease
Melanoma
subungual hemorrhage confusing patterns -
some cases may have band like pattern
onychomycosis rare pattern
band like pigmentation
when should fungal infection be considered as cause of pigmentation?
When all other causes excluded
trauma induced pigmentation - cause -
due to friction 2nd toe over first one
trauma induced pigmentation - common sites -
external aspect big toe
intimal aspect big toe
bowen’s disease - relationship of pigmentation to skin type
on skin pigmentation usually observed in dark skin
on nail pigmentation can occur in light skinned individuals
is Bowen’s disease on nail common?
no, it is very rare.
onychomatricoma - what is it?
Rare tumour
Specific to nail unit
Dt proliferation of nail matrix.
onychomatricoma - how does it enter into differential
May produce pigmented band on nail unit
melanonychia striata longitudinalis - problems with surgery
very painful
will likely disfigure the nail and may lead to functional problems with the digit
Clinical algorithm for avoiding biopsy
Acquired during childhood
Polydactlylic
Stable
Another good explanation - drug, ethnicity etc
Clinical algorithm for avoiding biopsy
Acquired during childhood Polydactlylic Stable Another good explanation - drug, ethnicity etc No periungual inolvement.
Melanoma of nail is most common melanoma in ….
black people who also have ethnic pigmentation
Clinical algorithm in favour of biopsy
Acquired during adulthood
Monodactylic
Changes over time - long period of observation
Peri-ungual involvement. (Hutchinson’s sign)
Polychromia
Triangular shaped
Clinical algorithm in favour of biopsy
Acquired during adulthood
Monodactylic
Changes over time - long period of observation
Peri-ungual involvement. (Hutchinson’s sign)
Polychromia
Triangular shaped (adult)
Changes of plate - erosion/ longitudinal groove
Triangular shape in adult means …
lesion is enlarging faster than nail is growing
Hairpin vessels surrounded by white tissue in favour of …
keratinizing tumour in nail unit
Atypical vessels, linear irregular, milky red areas, multiple types of vessels in favour of …
suggestive of melanoma
Remnant of pigmentation on Dermoscopy in favour of …
malignancy, likely melanoma
Blood spots, due to …
hemorrhage under nail plate
Blood spots, colour
not specific - purple or red, recent
black or brown, older
Blood spot, shape
Proximal rounded
Distal filamentous
Blood spots are observed in ……. % of melanomas of nail unit.
60%
Blood spots are observed in ……. % of SCC of nail unit.
25%
Blood spots - management
ensure lesion resolves over time. 4 + 12 months
Background pigment
Brown - significant melanocytic hyperplasia.
Grey or yellowish - increased contact of melanin in keratinocytes
Melanocytic lesions - colour is largely related to …
skin type
Brown longitudinal lines - benign
brown background, lines are regular in colour, spacing, and thickness
Brown longitudinal lines - melanoma
irregular colour, spacing, thickness
rarely parallelism disruption
Greyish or grey yellowish background pigment
Ungual Lentigo Ethnic pigmentation (darker skin) Laugier Hunziker Drug induced Repetitive trauma (darker skin)
Micro-hutchinson’s sign. (Rare)
Pigmentation of peri-ungual skin only observed with Dermoscopy.
Micro-hutchinson’s sign, significance…
Usually melanoma
Longitudinal whitish/ yellowish pigmentation is known as …
Longitudinal leuco/xanthonychia.
Longitudinal whitish/ yellowish pigmentation is known as …
Longitudinal leuco/xanthonychia.
Yellowish pigmentation is significant when ….
associated with distal subungal hyperkeratosis
Yellowish pigmentation is significant when ….
associated with distal subungal hyperkeratosis
Yellowish pigmentation associated with distal subungal hyperkeratosis suggests that …
there is a keratinizing tumour in nail matrix.
Yellowish pigmentation associated with distal subungal hyperkeratosis may also be associated with …
erosion of distal nail plate or longitudinal grooves in the nail plate
distal subungal hyperkeratosis is observed by …
examination of the distal nail unit by Dermoscopy
splinter hemorrhages are common finding in ….
nail unit tumours
Longitudinal leuco/xanthonychia is observed in % SCC
60%
Longitudinal leuco/xanthonychia is observed in % Onychomatricoma
53%
Longitudinal leuco/xanthonychia is observed in which other lesions?
Hemangioma 30%
Glomus cell tumour 30%
subungal distal hyperkeratosis is observed in % SCC
73%
subungal distal hyperkeratosis is observed in % Onychomatricoma
70%
Linear micro-hemorrhages are common in …
any type of malignant tumour
Linear micro-hemorrhages in tumours manifest as …
linear hemorrhages in band-like fashion
Linear micro-hemorrhages without pigmentation good sign of …
keratinizing tumour
Linear micro-hemorrhages occurs in what type of melanoma?
Advanced melanoma
Linear micro-hemorrhages observed in % onychomatricoma
67%
Linear micro-hemorrhages observed in % SCC
35%
Linear micro-hemorrhages observed in % Achromic malignant melanoma
40%
Pigmented melanoma Dermoscopy features: Common
Brown background (95%) Irregular pattern of lines (95%)
Pigmented melanoma Dermoscopy features: Uncommon
Micro Hutchinson’s sign 15%
Splinter hemorrhages 5% (advanced cases)
Nail-matrix melanocytic nevus dermoscopic patterns
Brown background 100%
Regular pattern of lines 94%
Subungual hemorrhage dermoscopic patterns
Blood spot 100%
- No other sign
- Clearance of lesion 3-6 months
When looking at subungual hemorrhage always ….
use the Dermoscope
Nail unit lentigo and lentiginosis
Grey lines 93%
No other change of nail plate
Grey lines 93%, No other change of nail plate also found in ….
Drug induced pigmentation
Chronic trauma inducted pigmentation
Ethnic type pigmentation
Pigmented Bowen’s disease uncommon Dermoscopy features
Subungual distal hyperkeratosis 70%
Longitudinal leuco-xanthonychia 60%
Polychromia (grey, white, yellow, red) 45%
Triangular distal onycholysis, convex deformity and yellow spot 40%
Linear microhemorrhages (35%)
Onychomatricoma
Subungual hyperkeratosis (73%) Linear microhemorrhages (67%) Convex deformity of the nail plate, longitudinal leucoxanthonychia (53%) Triangular distal onycholysis
Follow u p with doubtful lesions
4,8,12,18 months
Probably with too early surgery -
very early melanoma shows few atypical melanocytes - can confuse pathologist.
Clinical management algorithm
Atypical > Surgical biopsy
Non atypical > 4 month control > no modification> annual follow up.
Dermoscopy nail bed and matrix - non melanocytic
homogenous pigmentation - brown or grey
Dermoscopy nail bed and matrix - melanocytic
bands
Dermoscopy nail bed and matrix - benign patterns
Non melanocytic
Lines regular
Lines regular + regular globules
