Rare skin tumours Flashcards
diagnosis problems
non specific criteria
workup protocol
recognizing associated syndromes
treatment and follow up problems
lack of guidelines
Keyword in management of rare tumours
Multidisciplinary
Tumours we are covering
Tumours of fibrous tissue Merkel cell carcinoma Angiosarcoma Adnexal tumours Sebaceous tumours
Tumours of fibrous tissue
Atypical fibroxanthoma
Malignant fibrous histiocytoma (Malignant part of above)
Dermatofibrosarcoma protuberans
Atypical fibroxanthoma - clinical
elderly - Mainly men sun exposed - Usually head rapidly enlarging reddish dome shaped nodule often eroded or crusted surface darker hue dt hemosiderin deposition
Atypical fibroxanthoma - Ddx
Melanoma, BCC, SCC
Atypical fibroxanthoma - Dermoscopy
reddish and whitish areas - majority non pigmented
white structureless and or red structureless
white lines
may have white circles
polymorphous vascular pattern - vessels usually fine, linear
ulceration, crusting and keratin masses
Atypical fibroxanthoma - management
tendency to recur after incomplete excision > wide local excision
Atypical fibroxanthoma - prognosis
excellent prognosis
Malignant histiocytoma - clinical
elderly
sun exposed
enlarging subcutaneous nodule, may have significant size and ulcerate
Malignant histiocytoma - ddx
bcc, scc, melanoma
Malignant histiocytoma - Dermoscopy
Polymorphous vessels
Ulceration
Hemorrhage
Malignant histiocytoma - Management
Wide local excision
Adjuvant radioRx
Chemotherapy
Malignant histiocytoma - Prognosis
overall survival 50%
aggressive tumour
metastasizes
Malignant histiocytoma - histopathology pitfall
Can confuse atypical fibroxanthoma with malignant histiocytoma
Dermatofibrosarcoma protuburans - clinical
one or more firm, erythematous nodules or plaques
resembles scar but no h/o scar
may enlarge slowly over many years
May ulcerated or suppurate
Dermatofibrosarcoma protuburans - incidence
1% of soft tissue sarcomas
most common cutaneous sarcoma
Dermatofibrosarcoma protuburans - Ddx
dermatofibroma
Dermatofibrosarcoma protuburans - Dermoscopy
reddish background colour
fine linear vessels - may be arborizing
no criteria for dermatofibroma
Dermatofibrosarcoma protuburans - Malignant potential
Low to intermediate
rarely metastasizes
locally aggressive
high recurrence rate
Dermatofibrosarcoma protuburans - management
Wide local excision - 5 cm
Cutaneous angiosarcoma of head and neck - clinical
Unique entity
elderly men
poor prognosis
Cutaneous angiosarcoma - associated with lymphedema
occurring years after radiation
occurring after years of lymphedema
Dermoscopy head and neck angiosarcoma
Typical colours of vascular tumours - red, purple, blue and white lines in nodular area
Merckel cell carcinoma - Epidemiology
0.2-0.45 cases per 100 000
100 times rarer than melanoma
increasing incidence recent years
Merckel cell carcinoma - Clinical
sun exposed - because immune suppressed
mainly elderly but not only
rapidly enlarging reddish dome shaped nodule
Merckel cell carcinoma - Dermoscopy
milky red area
polymorphous vascular pattern
may be arborizing
white lines
Merckel cell carcinoma - Management
Wide local excision.
Some recommend sentinel bx.
Some recommend only wide excision and radiation.
role of radiotherapy debated