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3	1. Trichofolliculoma - nodule with haircluster - usually on face (head/neck) - dilated primar follicle(s) with radiating sec. follicles with trichogenesis surrounding fibrous stroma Sebaceous variant: seb. diff.
4	2. Trichoadenoma (of Nikolowski) - usually on face, also buttock - keratinizing cysts, little/no strands - squamous epithelium, no basaloid component - Like multiple Æ infundibulae
5	3. Trichoepithelioma - solitary: adults, usually face, also ather 0.5cm, if bigger, usual trichoblastoma - multiple: AD, children, F>M, mostly central face (9p21) can be associated with cylindromas, TE, milia and spiradenomas (Brooke-Spiegler Sn: 16q12-13) - Desmoplastic (see further) - (Ackerman, 2000: trichoepithelioma ® trichoblastoma)
6	3. Trichoepithelioma
7	4. Desmoplastic trichoepithelioma
8	5. Trichoblastoma Pred. head/neck + other Often large (3cm: dermis/subcutis), Mostly elderly Behave benign, but few true malignant cases are reported (long standing, volume increase) Usually no clefting deep extension into subcutis, with stromal induction (!) Can be pigmented (pigm. Trbl/melanotrichoblastoma)
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10	6. Trichogerminoma Additional features: “zellballen” reminiscent of hair bulb
11	7. Trichoblastic fibroma - rare Trichoblastoma, but with more stroma: biphasic Syn. Giant cell trichoepith. usually dermal well circumscribed
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14	1. dilated porus of Winer “Comedo-like” lesion face / neck, adult, M > F Vertically orientated cone with irregular budding, no prom. primitive hair follicles central epidermal keratinisation Mid- and lower dermis
15	2. Pilar Sheet acanthoma upper lip, older central plug with keratin debris Multilobulated cystic No or little stromal induction central dilatation with variable lobular primitive differentiation
16	3. Trichilemmoma
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18	1. Pilomatrixoma
19	2. Malignant Pilomatrixoma
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22	Naevus sebaceous (of Jadassohn) (ofganoïd nevus) head, forehead, face Present at birth: elevated plaque, 1- 6 cm if lesions get older: verrucous / nodulair, evt. + secund. tumor/ look for it… In 50 % of the cases: + apocrine glands
23	2. sebaceous hyperplasia elevated papule, “yellowish” face, solitary or multiple rather older then young central sebaceous duct with radiating sebaceous glands sebaceous glands reach the epiderm clinically like “BCC”
24	3. sebaceous adenoma nodule on face (nose/cheek) or head, solitary, older Mean 0,5 cm, bigger can usually mature sebaceous glands + basaloid component well circumscribed Clin. inf. : BCC Ass. Muir-Torre Sn: make note
25	4. Sebaceoma (Seb. Epitheloma) Troy and Ackerman BCC + sebaceous differentiation ?? basaloid predominace !! sometimes polypoïd, adenoïd, cribriform, evt. + keratocysts F > M, older, face and scalp mitoses can, usually sparse but no atypia, no clefting, no pallisading if more atypia: evt. “atypical seb. Epithelioma” on cond. of well circumscribed - ass. possible with Muir torre Sn., especially if multiple !!
26	5. sebaceous Carcinoma typical: ocular (Meibomian glands) Non-oculair: rare, head/neck, elderly can metastasize ( 1/3 in the ocular lesions) usually undifferentiated basaloid cells with sometimes difficult to find sebaceous differentiation atypia/mitosis/nuclear variability infiltrative pattern, no prominent clefting/pallis
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29	1. Apocrine hydrocystoma Solit. lesion face Translucent blue nodule/cyst Single/multilocular papillary projections Decapitation secretion Double layer: myoep/secr
30	2. Hydradenoma papilliferum Adult females Labia majora, perineal, perianal Dermal cyst with tubular and papillary projections usual double layer with myoepithelium
31	3. Syringocystadenoma papilliferum Birth/children/joung adults head, face, forehead 1-3cm solitary plaque or linear papules, evt. warty 1/3 ass. with nevus seb. Evt. + BCC (10%) In continuity with epidermis Invaginating part with tubulopapillary projections Lots of plasmacells = typical ! Look for ass. nev seb (apocr. gl)
32	4. Apocrine carcinoma very rare, not well documented 2 till 8 cm Compare with eccrine adenocarcinoma but with apocrine differentiation infiltrating, (atypical) mitoses, atypia Axilla/anogenital: apocrine locations usual look of an adenocarcinoma with sometimes hard to find apocrine differentiation
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35	1. eccrine hydrocystoma retentioncyst F > M bluish lesion face, mostly periorbital More in summer DD/ apocrine hydrocystoma
36	2. Syringoma F > M mostly lower eyelid multiple skincolored papules Clear cell variant: » DM rare: axilla, head, vulva, acral linear Double layered epithelium typical “comma-shape” Carefull with “shave” !!
37	3. poroma group (Acrospiroma) A. Hydroacathoma simplex B. eccrine poroma C. eccrine hydradenoma GEN: the epithelium has a monotonous, “clonal” “transitional aspect”; “Brenner-like”
38	A. Hydroacanthoma simplex adults Syn. Epid. acrospiroma mostly leg solitary plaque Intraepithelial nests , as if it were “in situ” nests Look for ductal diff. DD/ clear cell acanthoma clonal seb. keratose (malignant variant): more atypia
39	B. eccrine poroma adults Acral (palmar/soles) solitary, pink-red, sometimes pigmented Asymptomatic, tender, sometimes pedunculated “candle” Ductal differantiation DD/ seb. Ker, BCC, spino malignant: more atypia/mitoses infiltrative
40	C. eccrine Hydradenoma Synonyms: - Derm. (ecc) Acrospiroma - Clear cell hydradenoma - Solid cystic hydradenoma,… sometimes ulcerated/cystic Lots of histological variants well circumscribed !! 1 - 2 mitosis /10HPF can if lots of mitoses and atypia: ® “atypical nod. Hydrad.”
41	4. Cylindroma adults, F > M head / face 90% solitary, usual <1cm Multiple: AD: turban tumor Ancell-Spiegler Sn - mult. TrichoEp. - eccr. Spirad. well circumscribed basaloid nests (jigsaw) with prominent BM (PAS+) periferal pallisading malignant: 19 cases/atypia/M+
42	5. Eccrine Spiradenoma painfull! (ANGEL) head / neck usual < 1 cm multiple can two celtypes ! DD/ BCC (clefting) Cylindroma
43	6. Chondroid Syringoma Syn: mixed tumor head / neck 0.5 till 3 cm well circumscribed Derm/subcut » pleom. adenoma Tubuli in myxochondroïd stroma malignant: -rare (25 cases) -extremities/body -not circumscribed -after mult. recurr.
44	7. Papillary (eccrine) adenoma rare mostly extremities Mor in negro-african; F>M Globally well circumscribed no prom. atypia rare mitoses Double layered epithelium with papillary projections DD/ Dig. Pap. AdenoCa: more mitosis, atypia, deeper
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48	9. Eccrine ductal carcinoma high grade tumor, M+ head / neck, 1-5 cm can ulcerate infiltrative well ® poor diff Looks like “adeno” Suggest exclusion of cut. metastasis of fi. breast / G-I
49	10. Microcystic Adnexal Carcinoma Upper lip, nasolab. fold chin, cheek indurated plaque/nod DEEP !! « syring/Tr-ep ALWAYS perineural Carefull with (shave) biopsy Recurrence for life if not recognized at first time Possible in younger persons ! clinically: usually BCC
50	10. Microcystic Adnexal Carcinoma Histology: - poorly circumscribed - deep infiltration, in sc fat - nests/ fine strands - Minimal atypia/mitoses - syringoma like but ¯ - superf. evt cystic / + Ca² - perineural: look for it ! - eccrine ducts: EMA/CEA
51	11. Eccrine Epithelioma head Only 11 cases actually MAC but less cystic dilatation more superficially and less Ca² Hist.: otherwise identical as MAC with focus on perineural invasion
52	12. Adenoïd Cystic Carcinoma Head Deep nodule/plaque Histology as MAC but with cribriform architecture, evt. pap proj. also perineural !! can metastasize (rare) DD/ BCC: paliss/clefting
53	13. (Eccrine) Mucinous Carcinoma rare, 8-88 (gem. 64) mostly head/neck nodule, slow growing Locally aggressive metastasis rare Rather deep infiltrating DD. with breast/G-I
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