51 - Porokeratosis

Question 1

Porokeratosis usually occurs in

Answer 1

Fair-skinned individuals

Question 2

Begins during infancy or childhood
Asymptotic, small, brown to skin-colored, annular plaques with a characteristic annular border
Male predominance

Answer 2

Porokeratosis of Mibelli

Question 3

Giant porokeratoses may occur in porokeratosis of Mibelli and occur predominantly on the

Answer 3

Lower leg and foot

Question 4

Large porokeratoses are associated with

Answer 4

Higher malignant potential

Question 5

Most common of the porokeratoses

Answer 5

Disseminated superficial actinic porokeratosis

Question 6

More generalized than other forms of porokeratosis
Typically more than 50 lesions located predominantly in sun-exposed sites
Spare the palms, soles, and mucous membranes
Hyperkeratotic border is subtler
Female predominance

Answer 6

Disseminated superficial actinic porokeratosis

Question 7

Onset in the third or fourth decade
Do not spare sun-protected areas
More than 100 lesions may be present

Answer 7

Disseminated superficial porokeratosis

Question 8

Presents early in childhood
Mosaic manifestation of porokeratosis
Unilateral lesion confined to an extremity following Blashcko lines

Answer 8

Linear porokeratosis

Question 9

Highest potential for malignant degeneration

Answer 9

Linear porokeratosis

Question 10

Small, relatively uniform lessons that initially appear on the palms and soles
Palmar and plantar lesions are generally more hyperkeratotic
Appears during adolescence or early adulthood
Male predominance

Answer 10

Porokeratosis palmaris et plantaris disseminata

Question 11

Appears during adolescence or adulthood
May be seen concomitantly with other types of porokeratosis
Multiple minute and discrete punctate, hyperkeratotic lesions surrounded by a thin, raised margin on the palms and soles

Answer 11

Punctate porokeratosis

Question 12

Small, widespread porokeratotic papules from 1 month of age, predominantly affecting the face and extremities
Autosomal recessive trait

Answer 12

CDAGS syndrome (craniosynostosis and clavicular hypoplasia, delayed closure of the fontanel, anal anomalies, genitourinary malformations, skin eruption) or
CAP syndrome (craniosynostosis, anal anomalies, porokeratosis)

Question 13

Gene mutation: porokeratosis of Mibelli

Answer 13

Phosphomevalonate kinase (PVMK)

Question 14

Gene mutation: DSAP

Answer 14

Mevalonate kinase (MVK)

Question 15

Malignant degeneration has been described in all variants of porokeratosis, except

Answer 15

Punctate porokeratosis

Question 16

On histopathology, characteristic changes are evident at the _____ of the lesion

Answer 16

Raised and advancing edge

Question 17

Stratum corneum is hyperkeratotic, with a thin column of poorly staining parakeratotic cells, the

Answer 17

Cornoid lamella

Question 18

Although characteristic of porokeratosis, the cornoid lamella is not pathognomonic and may also be found in other conditions, such as

Answer 18

Viral warts
Some ichthyosis
Nevoid hyperkeratoses

Question 19

First line topical treatment for porokeratosis

Answer 19

Photoprotection

5-fluorouracil

Question 20

First line surgical therapy for porokeratosis

Answer 20

Cryotherapy

Question 21

Malignancy is thought to arise in _____% of individuals

Answer 21

7-11

Question 22

Most frequently associated tumor

Answer 22

SCC