3: Pathology of pigmented lesions Flashcards Preview

Dermatology Week 3 2017/18 > 3: Pathology of pigmented lesions > Flashcards

Flashcards in 3: Pathology of pigmented lesions Deck (49)
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1
Q

Which aspects of the skin can tumours arise from?

A

Epidermis

Melanocytes

Dermis

Appendages

Lymphoid elements

2
Q

What does in-situ mean in relation to invasive?

A

Limited to epidermis only

3
Q

From which embryological structure do melanocytes come from?

A

Neural crest

4
Q

What are precursor melanocytes called?

A

Melanoblasts

5
Q

In which epidermal layer are melanocytes found?

A

Basal layer

6
Q

What is the ratio of melanocytes : basal keratinocytes?

A

1 : 10

7
Q

____ transfer melanin to ___ through their ___ processes.

A

Melanocytes , keratinocytes , dendritic

8
Q

What does melanin protect keratinocytes from?

A

UV radiation

9
Q

What is the technical names for freckles?

A

Ephilides

10
Q

What are freckles?

A

Patchy increases in melanin production

11
Q

When do freckles appear?

A

After UV exposure

12
Q

What are actinic lentigines (sing. lentigo)?

A

“Liver spots”

13
Q

What is the technical name for a birthmark?

A

Melanocytic naevi

14
Q

If a melanocytic naevi is big, what is at risk of turning into?

A

Melanoma

15
Q

What are the two main types of naevi?

A

Congenital and acquired

16
Q

What term, describing benign abnormal growth, can be used instead of naevi?

A

Hamartoma

17
Q

What are the three terms used to describe acquired melanocytic naevi as they sink into the dermis over time?

What does each stage look like?

A

Junctional - flat and circular

Compound - raised

Intradermal - raised and hairy

18
Q

What can dysplastic naevi turn into?

A

Melanoma

19
Q

The two atypical naevi - ___ naevi and ___ naevi - are totally (benign / malignant).

A

halo , blue

benign

20
Q

Which kind of rare naevi occur in children and resemble melanoma, but are actually benign?

A

Spitz naevi

21
Q

If you are unsure whether or not a lesion is a benign naevus or a malignant melanoma, refer to?

A

Dermatology

22
Q

What can arise from dysplastic naevi?

A

Malignant melanoma

23
Q

Malignant melanoma is more common in (men / women),

A

women

24
Q

What is the biggest risk factor for developing malignant melanoma?

A

UV exposure - sun, sunbeds

25
Q

Malignant melanoma risk is also tied to a person’s ____.

A

genetics

26
Q

Where can malignant melanomas arise?

A

Literally anywhere

27
Q

What are some signs which should make you suspect malignant melanoma in a skin lesion?

A

ABCDE

E being changes in shape, size, bleeding, ulceration, new nodules…

28
Q

What are the four types of melanoma?

A

Superficial spreading

Acral / mucosal

Lentigo maligna

Nodular

29
Q

Where do superficial spreading melanomas appear?

A

Trunk and limbs

30
Q

Where do acral melanomas appear?

A

Fingers / toes + nails

31
Q

What is acral melanoma often mistaken for?

A

Nail trauma

32
Q

Where does lentigo maligna melanoma appear?

Why?

A

Face / neck / scalp

Sun damage

33
Q

What is lentigo maligna a complicated name for?

A

Melanoma arising for actinic/solar lentigo - macules of pigment and melanocytes caused by UV damage

34
Q

What is the difference between lentigo maligna and lentigo maligna melanoma?

A

Lentigo maligna is confined to the epidermis and hasn’t started to invade yet

Lentigo maligna melanoma is invading

35
Q

What are the two phases of malignant melanoma growth?

A

Radial / Horizontal growth phase - tumour is in-situ

Vertical growth phase - tumour is invading dermis

36
Q

Only melanomas in the (horizontal / vertical) growth phase can metastasise.

A

vertical

37
Q

What type of melanoma is considered more aggresive because it goes straight into the vertical growth phase?

A

Nodular melanoma

38
Q

What does the Breslow thickness measure?

A

Distance from deepest part of tumour to the granular layer

39
Q

Apart from a high Breslow thickness, what are two another indicator of poor melanoma prognosis?

A

Bleeding

Ulceration

40
Q

By which means can melanoma spread around the body?

A

Lymph nodes > Lymphatics

Blood vessels

41
Q

Where can metastatic melanoma end up?

A

Heart

Lungs

Liver

GI tract

Brain

Skin

42
Q

If a melanoma is less than 1mm thick, what margin of skin is excised around it?

> 1mm?

A

1cm

2cm

43
Q

What else can be removed along with the malignant melanoma itself?

A

Lymph nodes

44
Q

How is advanced malignant melanoma treated?

A

Chemotherapy

Immunotherapy

45
Q

Mutations of which gene are responsible for malignant melanoma on sun-exposed skin?

A

B-RAF

46
Q

Which type of gene is B-RAF?

A

Oncogene

47
Q

The proto-oncogene for B-RAF is very (strong / weak).

A

weak

48
Q

Which pathway is involved in malignant melanoma on sun-exposed skin?

A

RAS / RAF / MAPK pathway

49
Q

Which drug can be used to block the RAS / RAF / MAPK pathway to treat malignant melanoma?

A

Imatinib