5: Pathology of non-pigmented lesions Flashcards
What is a common benign epidermal tumour with a raised, stuck-on appearance?
Seborrhoeic keratosis
Name three precancerous dysplasias which can develop into SCCs.
Actinic keratoses
Bowen’s disease
Viral warts
What are the two common non-pigmented malignant lesions?
Basal cell carcinomas
Squamous cell carcinomas
What benign lesion is common in aging skin?
What are they made of?
Seborrhoeic keratoses
Keratinocytes
How would you describe a seborrhoeic keratosis?
Brown
Stuck-on appearance
Pitted / warty surface
Well-defined borders
What sign of internal malignancy involves the eruption of loads of seborrhoeic keratoses?
Leser-Trelat sign
What are seborrhoeic keratoses also known as?
Basal cell papilloma
What is the malignant version of a seborrhoeic keratosis?
Basal cell carcinoma
Where do basal cell carcinomas appear?
Sun-exposed skin
What are the three types of basal cell carcinoma?
Nodular
Superficial
Morphoeic (infiltrative, spread deep to the epidermis)
Which type of BCC is the most important to identify?
Infiltrative / morphoeic
What do BCCs look like?
Slow-growing
Pearly
Telangectasia
Do BCCs commonly metastasise?
No
How can BCCs kill / cause serious disability?
Infiltrating organs & structures e.g ears, eyes, brain
Which form of skin cancer has three common precursor dysplasias?
Squamous cell carcinoma
Where is Bowen’s disease commonly found?
Legs
Where are actinic keratoses commonly found?
Sun exposed skin:
Scalp, face, neck, dorsal hands
Where are viral lesions commonly found?
Anogenital surfaces
Which process do SCC precursor lesions go through?
Dysplasia
i.e abnormal epithelial growth, “atypia”
Bowen’s disease is essential SCC __-__.
in-situ
What does Bowen’s disease look like?
Scaly erythematous patches / plaques with an irregular border
Does Bowen’s disease invade the dermis?
No, epidermal lesion
plaques are flat
Bowen’s disease is most commonly seen in (men / women).
women
Bowen’s disease is often mistaken for which kind of skin disease?
Inflammatory skin disease
Name a SCC precursor caused by UV exposure, commonly seen on the scalp, face and hands.
Actinic keratosis
What are actinic keratoses also known as?
Solar keratoses
cuz of sun exposure
What happens histologically in actinic keratosis?
Rete ridges become elongated
Do actinic keratoses invade the dermis?
No
Which infectious agent causes lesions which may turn into SCCs?
Viruses
most commonly HPV
What is erythroplasia of Queryat?
Penile Bowen’s disease
Which virus is usually responsible for lesions which may turn into SCCs?
Human papilloma virus
The viral lesion on slide 33 resembles which other SCC precursor?
Bowen’s disease
What are the treatment options for SCC precursors (actinic keratoses, Bowen’s disease and viral lesions)?
Cryotherapy
Topical treatments
What are the common sites for SCCs?
Sun-exposed skin (face, ears, dorsal surface of hands)
On which chronic skin diseases can SCCs arise?
Leg ulcers
Burns
Which genetic condition involves DNA repair failure and predisposes patients to SCCs?
Xeroderma pigmentosum
What is the prognosis for BCCs and SCCs?
Generally good
What are the two main factors influencing SCC prognosis?
Thickness
Vascular/lymphatic involvement
What are sites for SCCs associated with poor prognosis?
Scalp
Nose
Ears
What structures can SCCs travel along to invade other tissues?
Nerve fibres
What pressure receptor / mechanoreceptor cells can become malignant?
Merkel cell carcinoma
Merkel cell carcinoma is the cutaneous equivalent of which lung cancer?
Small cell carcinoma
Which T-cell lymphoma presents like eczema but doesn’t clear up with topical steroids?
Mycosis fungoides
