Melanoma

Question 1

There are four main subtypes of melanoma. These are?

Answer 1

Superficial spreading
Nodular
Lentigo maligna
Acral lentiginous

Question 2

Frequency of melanoma?

Answer 2

Superficial spreading - 70% of cases
Nodular - Second commonest
Lentigo maligna - Less common
Acral lentiginous - rare form

Question 3

Superficial spreading typically affects?

Answer 3

Arms, legs, back and chest, young people

Question 4

Nodular typically affects?

Answer 4

Sun exposed skin, middle-aged people

Question 5

Lentigo maligna typically affects?

Answer 5

Chronically sun-exposed skin, older people

Question 6

Acral lentiginous typically affects?

Answer 6

Nails, palms or soles, African Americans or Asians

Question 7

Appearance of Superficial spreading?

Answer 7

A growing mole

Question 8

Appearance of nodular?

Answer 8

Red or black lump or lump which bleeds or oozes

Question 9

Appearance of Lentigo maligna?

Answer 9

A growing mole

Question 10

Appearance of Acral lentiginous?

Answer 10

Subungual pigmentation (Hutchinson’s sign) or on palms or feet

Question 11

There are other rare forms of melanoma including

Answer 11

desmoplastic melanoma, amelanotic melanoma, or melanoma arising in other parts of the body such as ocular melanoma.

Question 12

The main diagnostic features (major criteria):

Answer 12

Change in size
Change in shape
Change in colour

Question 13

Secondary features (minor criteria)

Answer 13

Diameter >= 7mm
Inflammation
Oozing or bleeding
Altered sensation

Question 14

Mx melanoma?

Answer 14

Suspicious lesions should undergo excision biopsy. The lesion should be removed in completely as incision biopsy can make subsequent histopathological assessment difficult.

Once the diagnosis is confirmed the pathology report should be reviewed to determine whether further re-excision of margins is required

Further treatments such as sentinel lymph node mapping, isolated limb perfusion and block dissection of regional lymph node groups should be selectively applied.

Question 15

Margins of excision?

Answer 15

Lesions 0-1mm thick: 1cm

Lesions 1-2mm thick: 1- 2cm (Depending upon site and pathological features)

Lesions 2-4mm: thick 2-3 cm (Depending upon site and pathological features)

Lesions >4 mm: thick 3cm

Question 16

single most important factor in determining prognosis of patients with malignant melanoma?

Answer 16

invasion depth of a tumour (Breslow depth)

Question 17

Breslow Thickness & Approximate 5 year survival?

Answer 17

< 0.75 m: 95-100%
0.76 - 1.50 mm: 80-96%
1.51 - 4 mm: 60-75%
> 4 mm: 50%

Question 18

What is Lentigo maligna?

Answer 18

Lentigo maligna is a type of melanoma in-situ. It typically progresses slowly but may at some stage become invasive causing lentigo maligna melanoma.

Question 19

Melanocytic naevi subtypes?

Answer 19

Congenital melanocytic naevi
Junctional melanocytic naevi
Compound naevi
Spitz naevus
Atypical naevus syndrome

Question 20

naevi Increased risk of malignant transformation?

Answer 20

Congenital melanocytic naevi

increased risk greatest for large lesions

Question 21

Describe Congenital melanocytic naevi

Answer 21

Typically appear at, or soon after, birth

Usually greater than 1cm diameter

Question 22

Describe Junctional melanocytic naevi

Answer 22

Circular macules
May have heterogeneous colour even within same lesion
Most naevi of the palms, soles and mucous membranes are of this type

Question 23

Describe Compound naevi

Answer 23

Domed pigmented nodules up to 1cm in diameter

Arise from junctional naevi, usually have uniform colour and are smooth

Question 24

Describe Spitz naevus

Answer 24

Usually develop over a few months in children
May be pink or red in colour, most common on face and legs
May grow up to 1cm and growth can be rapid, this usually results in excision

Question 25

Describe Atypical naevus syndrome

Answer 25

Atypical melanocytic naevi that may be autosomally dominantly inherited
Some individuals are at increased risk of melanoma (usually have mutations of CDKN2A gene
- Many people with atypical naevus syndrome AND a parent sibling with melanoma will develop melanoma