Melanoma

Question 1

How do junctional naevi present

Answer 1

common moles in prepubertal children, appearing as flat,
hairless, well-defined brown patches. On close inspection the normal skin markings are present and this
distinguishes them from melanomas

Question 2

How is a junctional naevus characterized histologically

Answer 2

Focal proliferation of melanocytes which remain in contact with the epidermis (Junctional activity)

Question 3

What is the natural history of a junctional naevus

Answer 3

Junctional –> Compound –> intradermal

Very few become malignant

Question 4

How do compound naevi present

Answer 4

These are commonly found in adolescents as dark brown or black, elevated or nodular lesions. They may
be hair-bearing

Question 5

What is seen histologically in a compound naevus

Answer 5

junctional activity as well as nests of naevus
cells in the dermis. The cells become smaller as they progress more deeply into the dermis. This is known as `maturation’

Question 6

Presentation of an intradermal naevus

Answer 6

Grossly, the appearance is variable. It can be flat, raised, nodular or pedunculated. It may be pigmented or
non-pigmented and hairs may be present

Question 7

Presentation of a spindle cell (Spitz) naevus

Answer 7

Grossly, it appears as a raised lesion, often occurring on the face with a characteristic reddishbrown colour

Question 8

How do dysplastic naevi differ from normal naevi

Answer 8

They are larger, more irregular in shape, indistinctly bordered and variably pigmented

Question 9

Where do dysplastic naevi occur

Answer 9

They are commonest on the trunk but tend also to occur in unusual sites such as the scalp, buttocks and
breast.

Question 10

Cumulative lifetime incidence of melanoma in a patient with dysplastic naevus

Answer 10

Lifetime incidence approaching 100 %

Question 11

Major aetiological factor of malignant melanoma

Answer 11

sunlight

Question 12

When should the development of malignancy within a naevus be suspected

Answer 12

• Change in size
• Change in outline
• Change in colour
• Change in elevation
• Change in the surface characteristics
• Change in the surrounding tissues
• intermittent itching or tingling
• Recurrent minor bleeding/ serous discharge

Question 13

4 Clinicopathological types of melanoma

Answer 13

1. Superficial spreading melanoma
2. Lentigo maligna melanoma
3. Nodular melanoma
4. Acral lentiginous melanoma

Question 14

What is the pre-metastatic phase of melanomas

Answer 14

the pre-metastatic phase is described as the radial growth phase and can be diagnosed clinically. During this period, the tumour grows radially without vertical penetration. Nodular melanoma, however, starts the vertical growth phase early

Question 15

Which are the most important prognostic factor in malignant melanoma

Answer 15

depth of penetration and location

Question 16

Where is superficial spreading melanoma seen

Answer 16

lesion is seen most often in early middle age on any part of the body, but especially on the lower legs of women

Question 17

How does Lentigo maligna melanoma develop

Answer 17

It starts as a Hutchinson’s melanotic freckle which
appears as a brown or black macular lesion looking like a smudge of boot polish. It may enlarge and recede producing an irregular outline with paler areas due to regression. Initially it is impalpable, but with invasion,
palpable nodules develop

Question 18

Which is the most common melanoma in the african population (seen as a separate clinical entity)

Answer 18

Acral lentiginous melanoma

Question 19

Which lesions have greater incidence of metastatic spread

Answer 19

• Lesions reaching Clark level III, IV and V or lesions more than 1. 5mm thick

Question 20

high risk areas (for recurrence) in malignant melanomas

Answer 20

upper back, posterolateral arm, posterior neck and posterior scalp

Question 21

management of melanoma

Answer 21

• lesions should be excised for histology (elliptical excison biopsy; exceptionally large lesions - incision biopsy)
• Once diagnosis is confirmed; further excision of the skin surrounding the tumour may be indicated
• Lesions with penetration less than 0.76 mm need a margin of 1 cm
• lesions deeper than 2 mm – a margin of excision should be 3 cm
• Closure: skin grafting/ local skin flaps on the back

Question 22

What parameters are used to microstage the melanoma

Answer 22

• Levels of invasion (Clarks levels)

- Depth of penetration (Breslow’s)

Question 23

When is Hyperthermic regional limb perfusion done

Answer 23

• Prophylactic treatment of lesions in the lower limb deeper than 1.5 m, to prevent local or in transit recurrence
• Therapeutically for patients who present with local recurrence

Question 24

What is the indication for prophylactic node dissection

Answer 24

During a mono-block resection when excision of the tumour and surrounding skin with lymph nodes is performed in continuity, occurring with a deeply penetrating primary tumour, which is situated over
or close to its draining lymph nodes

Question 25

When is therapeutic lymphadenectomy done

Answer 25

When one or more lymph nodes is clinicall involved

Question 26

What is the follow- up for patients with melanoma

Answer 26

Patients are examined clinically every two months
with routine chest x-rays and liver function tests at 6 monthly intervals for the first two years. In patients who are disease-free after two years, the period between follow-up visits is generally lengthened to a maximum of
6 months

Question 27

Which is the most effective single agent chemotherapy for malignant melanoma

Answer 27

DTIC

Question 28

What is the recommended radiotherapy for malignant melanoma

Answer 28

larger doses and the addition of hyperbaric oxygen may

provide satisfactory responses.