Pigmented Lesions

Question 1

Describe hyperactive melanocytes.

Answer 1

A flat lesion

• on skin: a freckle
• on mucosa: melanoitc macule

Question 2

Describe excess melanocytes in basal epithelium.

Answer 2

Large, often irregular, flat pigmented lesion

• on skin: lentigo sensilis (age spot)
• in mouth is usually regarded as a premalignant lesion

Question 3

Give an example of melanocytes stimulated by inflammation.

Answer 3

Smokers melansis

Question 4

What are the three types of nevus cells?

Answer 4

1) junction
2) compound
3) intradermal

Question 5

What is a nevus?

Answer 5

Clinically present as a raised lesion (in rare cases, may be flat)

• on skin: mole
• mucosa: nevus

Question 6

How are malignant melanocytes described?

Answer 6

Using ABCD guideline 
a- asymmetry
b- border irregularity
c- color variation
d- diameter greater than 6mm

Question 7

What are three syndromes associated with diffuse and multifocal pigmentations?

Answer 7

1) Peutz Jehger Syndrome - autosomal, intestinal polyposis, oral and peri-oral pigmentations
2) Addison’s disease - primary adrenal cortical insufficiency, pigmentation caused by oversecretion of ACTH and beta lipoprotein from the pituitary gland due to loss of adrenal cortical hormones that usually provide feed-back to control pituitary secretions
3) Hemochromatosis - excess iron deposition and excess melanin causing bronzing of the skin

Question 8

During differential diagnosis, what should be ruled out if the lesion is solitary?

Answer 8

melanoma

Question 9

If pigmentations are diffuse or multifocal, what can be ruled out?

Answer 9

systemic conditions and melanoms