Mystery behind labial and oral melanotic macules: Clinical, dermoscopic and pathological aspects of Laugier-Hunziker syndrome

Table 2 Distribution of involved locations of pigmentary lesions in Laugier-Hunziker syndrome

Involved locations		Frequency	Ref.
Lip		75% (154/206)	[1,3-16,18,19,21-25,27-29,31-38,40,41,43-52,54-68,70-73,75-78,80,83,85-88]
Oral cavity		68% (140/206)	[1,3-9,11-19,21-24,26,27,29,31-33,35-44,46,47,50-60,62-76,78,79,81,82,84-88]
Acral area	Nail	47% (96/206)	[1,3-10,12,14-17,19,22,23,25-27,31,32,34,39-41,43,44,47,49,50,52-54,56-59,61,63-66,68-72,77-84,86]
	Periungual area	8% (17/206)	[8,14,16,25,31,34,43,47,50,54,64,65,71,73,77,79,81]
	Finger	13% (26/206)	[5,8,9,11,14,19,21,41,43,49,55-57,59,60,66,70-72,74,76,84-86,88]
	Palm	4% (8/206)	[7,43,44,46,59,60,62,81]
	Toes	3% (6/206)	[19,56,59,70,84,86]
	Sole	3% (6/206)	[7,21,46,59,62]
Genitalia	Penis	24% (17/70)1	[20-23,46]
	Vulva or labia majora	10% (13/127)1	[7,12,15,17,21,30,58,74]
Anal mucosa and perianal area		1.5% (3/206)	[21,41]
Conjunctiva and sclera		4% (9/206)	[6,7,17,19,23,46,60,83]
Eyebrow and periorbital area		1.5% (3/206)	[41,53,71]
Pharynx		0.5% (1/206)	[4]
Esophagus		0.5% (1/206)	[44]
Neck, thorax, and abdomen		1% (2/206)	[25,81]
Back		0.5% (1/206)	[50]
Elbow		1% (2/206)	[43,76]
Pretibial area		0.5% (1/206)	[62]

¹Frequency of genitalia involvement of pigmentation was assessed according to the known sum of male or female cases.