Adnexal Neoplasms Flashcards
Syringoma
- Multiple small felsh-colored papules on woman’s face
- Bland ductal structures with cords and tadpoles in fibrotic stroma
- DDX: desmoplastic trichoepithelioma (follicular diff’n and calcs)
Chondroid syringoma
(mixed tumor of the skin)
dermal epithelial islands and branching strands containing ducts surrounded by abundant myxoid to chondroid stroma
Sites
Describe histology
DDX
Poroma
“eccrine poroma”
Often acral sites
Anastomosing strands of bland adnexal keratinocytes
Originates from epidermis and extends into dermis
Focal duct formation
(related to hidradenoma - mainly in dermis- and dermal duct tumor)
Spiradenoma
- “eccrine spiradenoma”
- lobules and nest of adnexal cells with central luminae
- contains 2 epithelial cell layers (smaller outer and larger inner)
- Eosinophilic hyaline droplets
- Cystic spaces
- prominent vessels with hemorrhage (not as common in cylindroma)
- Painful
Cylindroma
- jigsaw puzzle
- nests separated by thick basement membrane (also within nests)
- occasional ducts (less than in spiradenoma)
- hyaline droplets
- Brooke Spiegler
Dermal duct tumor
Hidradenoma (aka acrospiroma)
- Nodular, solid (first picture), and clear cell (second picture) types
- Variable ductal differentiation
- Basically the same as dermal poroma, dermal duct tumor
Hidradenoma papilliferum
- Perineal region of women
- dermal-based nodule of tubular and cystic structures with apocrine differentiation
Describe histology
Location
DDX
Immunos
Microcystic adnexal carcinoma
- Depressed plaque on face, esp upper lip of adults
- Superficial bland follicular crusts overlying deeply infiltrative epithelial strands with follicular and sweat duct formation, often perineural invasion
DDX:
- Sclerosing BCC - lacks superficial follicular cysts and ductal differentiation
- Desmoplastic trichoepithelioma - lacks deep invasion or perinerual invasion, has calcs, follicular but no ductal differentiation
Immunoperoxidase - CK7 and EMA Positive (negative in BCC and TE) and low ki-67 and p53 (high in BCC)
Histology
Location
Immunos
Extramammary paget’s disease
- Eroded plaque often genital or perineal (also axillae and eyelid)
Pagetoid intraepidermoid spread of large atypical cells with occasional signet ring cells or gland formation - Mucin
- PASD+
- Immunoperoxidase:
- GCDFP+
- CEA+
- CAM5.2+
- EMA+
- CK7+
- CK20-
- S100-
Sebaceous adenoma
- May indicate Muir Torre syndrome (HNPCC associated with MLH1, MSH2, MSH6)
- Circumscribed
- > 50% well-differentiated sebocytes
Sebaceoma
Clinical: a/w Muir Torre syndrome
Histo:
- circumscribed growth
- < 50% well-differentiated sebocytes
- > 50% bland basaloid cells
Sebaceous carcinoma
Clinical: eyelid and extraocular; aggressive tumor with frequent mets
Histology:
- infiltrative
- pagetoid spread
- atypia
- squamous or basaloid differentiation, but should find vacuolated cells
Immunoperoxidase:
- CAM5.2 +
- androgen +
- EMA +/- (lost in poorly differentiated)
- CK7 +/-
- GCDFP-
- CEA-
Trichoepithelioma
Basaloid, cribriform nodules with finger-like projections
Type of trichoblastoma
Seen in Brooke-Spiegler and Rombo syndromes
Mucin may be present in nests, but not in stroma
Multiple small papules in the nasolabial folds
Resemble BCC, but unlike BCC it has:
- concentric fibroblast-rich stroma instead of myxoid stroma
- papillary mesenchymal bodies
- horn cysts
- calcification
- clefts between collagen fibers within stroma not between nodules and stroma
- CD34+ stroma
- Peripheral positivity for BCL2 whereas BCC has strong, diffuse staining
- Ber-EP4 +/- (BCC strong positive)
Trichoblastoma
Large, deep nodular proliferation
Desmoplastic trichepithelioma
Infiltrating epithelial structures with cords and tadpole shapes in a fibrotic stroma
follicular differentiation and calcs are frequent (unlike infiltrating/sclerosing BCC)
DDX:
MAC
Morpheaform BCC
Immunoperoxidase: p53, Ki-67 negative (+ in BCC) and CK7 - (positive in MAC)
Pilomatricoma
Calcifying epithelioma of Malherbe
Clinical: head and neck nodule in kids or young adults
Nodular or cystic proliferation of hyperchromatic basaloid cells merging with central shadow cells; calcs and ossification
