Flashcards in 4.1 Histopathology of common skin neoplasms Deck (40):
What are the three layers of the skin?
What are the layers and components of the epidermis?
flat discoloured lesion up to 10mm
flat discoloured lesion >10mm
elevated (dome, flat topped) lesion up to 10mm
Elevated (dome) lesion >10mm
elevated flat topped lesion >10mm
fluid filled lesion up to 10mm
fluid filled raised lesion >10mm
pus filled raised lesion
thickened rough skin with prominent markings
traumatic lesion with breakage of the epidermis and raw liner area
What is hyperkeratosis
thickening of the stratum corneum
What is parakeratosis
retention of nuclei in stratum corneum
What is hypergranulosis
hyperplasia of the stratum corneum
What is acanthosis
Diffuse epidermal hyperplasia
What is papillomatosis
Surface elevation caused by hyperplasia and enlarged dermal papillae
What is spongioisis
intracellular edema of epidermis
What is dyskeratosis
abnormal premature keratinization below stratum granulosum
What neoplasms can you have of the keratinocytes
Actinic (solar) keratosis
What neoplasms can you have of basal cells?
What neoplasms can you have with melanocytes?
Lentigo (age spots)
Naevocellular naevi (moles)
What is the microscopic appearance of epidermal cysts?
Keratin debris containing cyst lined by benign squamous epithelium (found in the dermis) - benign
What is the appearance of actinic keratosis and who does it usually occur in?
Scaly patches due to too much keratin (confined to the epidermis) - usually in the elderly from sun exposure
What is the microscopic appearance of actinic keratosis?
Epidermal dysplastic (neoplastic but not invasive)
Solar elastosis of the dermal collagen
What is the treatment of actinic keratosis and why is it important?
Freezing, curettage, topical treatments, excision
Important because it is a precursor for SCC
What is the macroscopic appearance of SCC?
Nodular, scaly, ulcerated
- Red scaling plaques when in situ
- Nodular keratin producing when invaded
What is the microscopic appearance of SCC?
Invasion beyond BM
What is the appearance of Solar elastosis?
Looks blue as apposed to healthy pink collagen bundles
What is the macroscopic appearance of keratocnathoma?
What is the microscopic appearance of keratocanthoma?
Nodule with a central crater filled with keratin
What type of neoplasm is keratocanthoma?
Benign rapidly developing neoplasm which mimics a well differentiated SCC
What is the macroscopic appearance of seborrhoeic keratosis?
Raised warty lesions
What is the microscopic appearance of seborrhoeic keratosis?
Proliferation of benign basal cells
what is the macroscopic appearance of BCC?
Pearly papules with surface telangiectasia (blood vessels)
What is the microscopic appearance of BCC?
Malignant basal cells
Retraction artefact - clefting around
What are ephelis?
Freckles which appear after sun exposure
What is the microscopic appearance of ephelis?
Increased melanin pigment in basal layer but normal number of melanocytes
What are lentigo?
benign age spots which do not darken on sun exposure