Table 3.

Apocrine‐eccrine adnexal tumours. 217 cases in 122 articles ^a .

Benign	Cases/Articles (173/93)	M/F (71/66)	Age range (6/88)	Max diameter range (2–70)	Clinical morphology aspect	Dermoscopy
Cylindroma	8 (7 patients)/723,38,49,85,96,148,185	1/2	58–80	4–15	3: solitary pink‐red HN nodules	• 2: pink‐white or pink‐salmon background + linear irregular and unfocused arborizing vessels • 1: red‐yellowish background with white‐yellow scales/crusts and arborizing vessels
		3/1	43–80	8–30	5: pink nodules, 4 on HN, 1 on trunk, in patients with multiple lesions (3 had Brooke‐Spiegler syndrome)	• All: pink‐whitish background + orange hue or clods (2). White structureless scar‐like areas and white globules also seen. • Vessels: mainly unfocused and thin arborizing or linear irregular. • 2: pigmented criteria (blue globules and blue areas)
Spiradenoma	3/339,189,195	3/0	55–64	4–12	All solitary HN pigmented nodules	• pinkish‐orange background, peripheral yellowish globules, blue‐grey ovoid nests • Vessels: thin arborizing and linear irregular, mainly unfocused
Spiradenocylindroma	3/385,164,168	1/2	37–76	8–33	All pink‐blue nodules: 2 solitary, 1 multiple (Brooke‐Spiegler syndrome)	• blue globules and structureless areas over a whitish‐pinkish background with unfocused linear and thin arborizing vessels.
Hidradenoma (3 apocrine, 7 nodular, 1 clear cells, 1 eccrine)	17/913,36,52,110,157,169, 170,198,202	7/10	19–88	5–15	11 pink‐yellow‐red solitary nodules (4 ulcerated) on HN (5), trunk (3), limbs (3). 6 pigmented bluish solitary nodules (1 ulcerated) on HN (3), trunk (1), limbs (2) 3 on sebaceous nevus	• 4 nonpigmented with pink background + yellow central area, erosions and polymorphous vessels (1) or peripheral white collarette, central ulceration and glomerular/dotted vessels with white halo (1) or linear irregular vessels (2). • 13 with pigmented features: 1 pink background, blue eccentric, erosions and dotted, linear irregular and hairpin vessels; 4 pink‐white background with blue‐brown structureless areas + brown globules (1), eccentric ulceration (1), linear (2) or arborizing (1) vessels; 8 bluish background + yellow‐brown‐grey globules (3), erosions/ulceration (2) and linear irregular (3), arborizing (2) or polymorphous (1) vessels.
Hidradenoma papilliferum	7/325,141,188	1/6	22–65	5–25	All solitary nodules, 6 on genitalia (3 ulcerated and 2 pigmented), 1 on HN pigmented	• 3 pigmented: 2 blue homogenous with no vessels, 1 brown central and pink peripheral with dotted and linear irregular vessels • 4 nonpigmented: 1 white atrophic with arborizing and convoluted vessels, 3 with pink‐white background (orange hue in 1) and polymorphous vessels (dotted, glomerular, linear irregular) + peripheral white rim (2)
Hidroacanthoma simplex	11/832,65,106,113,123,162,170, 175,180,187	4/5	39–88	4–70	10 solitary plaques on lower limbs (5), HN (1), trunk (3), 1 unknown: 8 pigmented (brown), 3 ulcerated; 1 Asian 60 y/o patient with multiple plaques on lower limbs	• 9 pigmented: 5 with brown dots and globules on pinkish background + white‐yellow scales and erosions/eccentric ulceration (3), vessels: mainly dotted and linear irregular; 1: brown‐black pseudonetwork, white roundish structures and comedo‐like openings, without visible vessels; 1: brown‐black pseudonetwork central structureless pink‐red area with red lacunae surrounded by white halo, erosions and a white‐yellow keratin mass; 1: brownish background, white and yellow roundish structures and central linear irregular unfocused vessels; 1: white‐pink background with atypical vessels, blue‐black structureless areas with whitish veil and ulceration • 2 nonpigmented: pink‐yellowish background and polymorphic vessels (linear irregular, glomerular, cherry‐blossom, corkscrew)
Hidrocystoma (10 apocrine, 7 eccrine)	17/1016,36,45,55,89,112,193,201,203,204	7/10	30–76	2–10	10 solitary (9 apocrine, 1 eccrine) nodules: 5 pinkish, 5 bluish, on HN (7), trunk (2), acral sites (1). 1 on sebaceous nevus 7 patients with multiple papules on HN (6 eccrine, 1 apocrine): 6 pink‐whitish, only 1 bluish (Robinson‐type)	Solitary: 6 bluish background or homogenous areas + white lines (3) and linear irregular (2) or no visible (4) vessels; 2 pink background + orange hue and linear irregular vessels (1) or white peripheral and arborizing vessels (1); 2 grey‐white background and linear irregular vessels. Multiple: pink‐blue or brown‐grey background + white halo (4). Eccrine cases (no visible vessels), apocrine case (arborizing and linear irregular vessels
Poroma apocrine	1/118	1/0	35	12	Brown‐red HN plaque	1: irregular pigmented globules, milia‐like cysts and focal arborizing vessels
Poroma eccrine	81/354,5,11,15,19,32,41,47,50,54,58,62,63,71,78,80,83,88,95,97,98,108, 113,114,119,130,131,135,154,167,171,172,191,196,197	1/1	32–52	2	2: in 2 patients with multiple lesions (poromatosis). (1 Asian, 1 Caucasian)	1: erosions and glomerular vessels over a pinkish background 1: pinkish areas with salmon halo, white speckles and linear, hairpin and comma vessels
		33/15	32–86	3–30	82: solitary pink‐white or reddish (59) or pigmented (23) nodules or plaques, ulcerated in one quarter of cases, on acral sites (20), trunk (14), lower limbs (12)	Non pigmented: 57: white‐pink background + erosions or ulceration (26: 5 central), yellow structureless areas (12), milky‐red globules (11), white‐yellow scales (10), peripheral white collarette (9), milia‐like cysts (6). Vessels: mainly polymorphous (32), with cherry‐blossom or chalice‐like appearance (14 and 4) and surrounded by white halo (13); in 14 glomerular vesselswith white halo. Patterns: 2 globular (1 cobblestone), 2 white‐pink mesh bands reminiscent of a frog eggs aggregation (the mesh separates globules). Pigmented: 16: blue and/or brown background or structureless areas (in 5 brown‐blue peripheral and white‐pink central) + white‐yellow scales (9), brown‐black dots/globules (6), white lines (4), blue‐grey ovoid nests or leaf‐like areas (3). Vessels: mainly polymorphous or linear irregular (5 and 4). 7: pink‐white background + blue‐grey ovoid nests and arborizing vessels in 3 (surrounded by white halo in 2) brown‐blue globules in 3 + white peripheral halo in 2, central ulceration and polymorphous vessels in 2 brown‐black dots, brown peripheral globules and glomerular vessels surrounded by white halo in 1
Dermal duct tumour	2/132	1/n.r.	n.r.	6	Solitary brownish nodules on HN and lower limbs	1: grey‐brown background, with brown‐black dots and globules 1: yellowish papillomatous pattern with white circles Vessels: polymorphic in both cases (cherry‐blossom, glomerular and atypical) and surrounded by a white halo.
Syringocystadenoma papilliferum	10/920,27,29,51,56,87,104,176,202	5/5	6–74	3–15	9 solitary pink‐yellow or reddish nodules and plaques, mainly on the HN (7). 4 ulcerated, 5 on sebaceaous nevus. 1 Asian 12 y/o girl with multiple truncal lesions	most had erythematous background with white‐yellow areas and polymorphous vessels (linear irregular, glomerular, dotted, arborizing and horseshoe‐shaped) + white lines demarcating milky‐red or yellowish lobular structures (4), papillomatous projections surrounded by white circles (2), ulceration (4)
Syringoma	11 (10 patients)/917,44,74,143,153,160,178,186,206	3/4	23–57	3–5	8 multiple small brownish‐reddish papules mainly on trunk (7 cases). 7 were reported as eruptive, 1 with linear distribution.	All: light brownish‐pinkish + peripheral light brown pigmented network in the majority of cases. No visible vessels
		0/3	22–84	4–35	3 solitary nonpigmented papule, plaque and nodule, 2 on HN, 1 on genital area (2 Caucasians, 1 Asian). 1 on sebaceous nevus	All: white‐yellowish structures (scales, streaks) on a pinkish background + clustered dotted, short linear or classical arborizing vessels.
Tubular apocrine adenoma	2/282,107	2/0	49–63	3–7.5	HN black papule and ulcerated nodule	1: large blue‐grey ovoid nests and fine‐short vessels 1: white globules scattered uniformly over the entire surface, central red‐brown ulceration, fine arborizing, hairpin and glomerular vessels

Malignant	Cases/Articles (44/30)	M/F (23/15)	Age range (42/87)	Max diameter range (3–150)	Clinical morphologyaspect	Dermoscopy
Endocrine mucin‐producing sweat gland carcinoma	1/173	1/0	78	8	HN pink‐blue nodule	1: papillomatous appearance with pink‐red globules separated with a white to pink mesh of band and some blue globules. Fine linear irregular vessels.
Extrammary Paget's disease	17/107,26,34,35,43,75,122,126,144,166	6/1	48–80	25–130	13 pink‐reddish solitary plaques: 9 nonulcerated on genital area, excepted 1 patient with 1 additional lesion on trunk 4 ulcerated: 3 on genitalia and, 1 on the trunk	All: pink or milky‐red background + white dots/globules (2), or grey‐black dots (2), or red globules focally surrounded by white colour (1), or white clods surrounded by dotted vessels (1) Other criteria: white lines (2), white scales (6), ulceration (2). Vessels: 8 dotted (1 surrounded by white halo), 2 glomerular (1 surrounded by white halo), 1 polymorphous, 1 not visible Pattern: 1 strawberry, 1 cloud‐like structureless area defined as a combination of a white structureless area resembling diffuse layering of stratus clouds and white small round clods resembling fluffy cumulus clouds
		2/2	55–86	40–150	4 pigmented (brown‐black) plaques on genital area (2) or trunk (2)	1: brown‐white structureless areas with dark brown dots/globules surrounded by greyish halo, regression‐like areas and no visible vessels 1: brown‐red background with blue‐grey structureless areas and brown, blue‐grey and black globules sometimes linearly arranged and negative pigment network 1: white‐pink background with milky‐red areas, brown dots, grey rhomboidal structures, white scales and no visible vessels 1: pink background, white clods, glomerular vessels surrounded by white halo and lava lake structure: combination of branching white reticular lines and intermingling white clods resembling a lava lake inside a live volcanic crater
Microcystic adnexal carcinoma	4/424,46,72,177	3/1	42–78	4–30	2 solitary pink‐reddish papules, 1 plaque and 1 nodule, on HN and trunk.	1: central light brown pigmentation, structureless white areas, linear irregular vessels 1: brown‐grey dots on a pinkish‐white background with white‐yellow clods and scales and focused arborizing vessels 1: perilesional light brown pigmentation and a whitish structureless central area, with white‐yellowish clods of variable sizes, no visible vessels. 1: structureless white globules with monomorphic linear/serpentine vessel not crossing the midline.
Mucinous carcinoma	6/330,60,183	4/2	48–66	3–12	5 solitary nodules (1 ulcerated) and 1 macule on HN (5 Asian, 1 Caucasian) 4 nonpigmented (pink‐red or yellowish), 2 pigmented (brown‐grey or blue‐red)	3: white‐grey background with blue‐grey ovoid nests, grey dots and white structures + purple lacunae (2) or thin linear irregular vessels (2) 2: pink‐whitish background, yellow globules, white scales and polymorphous vessels (dotted, linear irregular, hairpin, atypical) 1: pinkish‐bluish background with central ulceration + white scales and thin linear irregular vessels (1)
Porocarcinoma (1 mixed between poroma and porocarcinoma)	12/814,57,61,70,147,171,179,190	6/6	48–87	6–40	8: pink‐reddish ulcerated nodules on lower limbs or acral sites; 2 on HN. 2: pigmented (blue‐brown) ulcerated nodule and papule	Most verrucous surface, pink‐whitish background with erosions or central ulceration and white‐yellowish scales and crusts. 3: pigmented criteria (brown or blue‐grey structureless areas, blue‐grey globules, black dots) Vessels: mostly polymorphic surrounded by white halo (dotted, glomerular, hairpin and linear irregular)
Squamoid eccrine ductal carcinoma	2/2102,158	1/1	75–76	6–20	1 pinkish papule and 1 blue‐grey ulcerated nodule both on HN	1: pinkish background with white globules and arborizing vessels 1: blue‐white colour, reddish‐purple lacunae, linear irregular peripheral vessels
Syringoid eccrine carcinoma	1/1117	0/1	43	13	1 HN pink‐red ulcerated plaque	1: pinkish background, central ulceration and yellow crusts, glomerular and dotted vessels with linear distribution
Syringomatous carcinoma	1/1132	0/1	83	8	1 Truncal red nodule	1: fine linear unfocused branched vessels, white‐pink homogenous backgrounds and surface scales

HN, head and neck.

^a See eReferences.