Skin appendages Flashcards
IFK may be caused by infection of the hair follicles with HSV
False HPV
Pilar sheath acanthoma is most commonly found on the cutaneous upper lip in the elderly
True
Trichoadenoma microscopically resembles a tumour of the infundibular portion of the hair follicle turned at 90 degrees
True ‘Turnadeniner’
Comedo naevus is always present at birth
False can be at birth or can appear duirng adult life
Pilar cyst is another name for a sebaceous cyst
False Pilar cyst is a trichilemmal cyst
Pilar cysts can be inherited in a recessive manner
False AD
Females get trichilemmal cyst more than males
True
Trichilemmal cysts are relatively common and usually occur on the scalp
True
A proliferating trichilemmal cyst is a rapidly enlarging lesion which arises from a trichilemmal cyst
True
Proliferating trichilemmal cyst commonly becomes malignant
False malignancy rare but often dysplastic on histo and should be completely excised otherwise tend to recur
A trichilemmoma is a tumour of the external root sheath
True The outer root sheath is the ‘trichilemma’ Tumours include; Trichilemmoma Proliferating/normal Trichilemmal (Pilar) cyst Trichilemmal carcinoma
Trichilemmomas have clear cells which are PAS +ve and diastase labile
True contain glycogen
Trichilemmoma is seen on the face in elderly pts
False On face usually in young-middle age
A hair follicle naevus is a plaque composed of a cluster of vellus hair follicles
True may just look like dense patch of vellus hairs
Faun-tail naevus is the same as a Becker’s naevus
False It is a hair follicle naevus on the sacrum
Eruptive vellus hair cysts are a feature of pachyonychia congenita
True can also be sporadic or a familial trait
Eruptive vellus hair cysts develop on the back in the second decade of life
False on chest in second decade but rarely elsewhere including face
Eruptive vellus hair cysts pathologicallly strongly resemble epidermoid cysts but with hairs
False strongly resemble steatocystoma but with hairs Epithelial lined cyst located in the mid dermis
Eruptive vellus hair cysts are due to occlusion and cystic dilatation of vellus hair follicles
True
A trichofolliculoma is a flat leison with a single protruding hair
False small raised nodule with several gairs protruding from a single orifice
Trichofolliculoma is a tumour of the external root sheath
False Trichofolliculoma is a hamartoma of the pilosebaceous follicle - it is in the hair germ tumour group; o Trichofolliculoma o Trichoepithelioma o Desmoplastic trichoepithelioma o Trichoblastoma
Trichofolliculomas occur in young adults esp on the face and can also occur on the vulva
True Vulval trichoepithelioma is rare but is associated with VIN
Trichoepithelioma is a variant of trichofolliculoma
False Trichoepithelioma is a variant of trichoblastoma
Trichoepithelioma is a small slightly raised pearly lesion on the face
True
Trichoepithelioma occurs singly or multiply usually in young people
True
Trichoepithelioma is a sporadic lesion without associations
False cam be sporadic or familial AD trait some familial cases have Brooke-Spiegler syndrome Occur on the genitals in Bazex-Dupre-Christol
Epithelioma adenoides cysticum is a syndrome of multiple angiofibromas
False Rare syndrome of multiple large, yellow-pink or bluish trichoepitheliomas
Desmoplastic trichoepithelioma (DTE) occurs in young people and clinically may resemble a BCC
True Plaque with raised rolled edge - often looks even more BCC like than standard trichoepitheliomas do
Histologically DTE resemble a nodular BCC
False Can resemble sclerosing (morphoeic) BCC Alos closely resembles Microcystic adnexal carcinoma (MAC)
DTE conatins Merkel cells which stain with CK20 and can be used to differentiate it from MAC
True
Trichoepithelioma is the most common tumour arising in a naevus sebaceous
False Trichoblastoma is
There are reports of trichoblastoma arising after low dose depilatory Xray treatment (as used to be used for tinea corporis)
True
Trichoblastoma can be difficult to differentiate histologically from follicular BCC
True Merkel cells in trichoblastoma can help differentiate
Basaloid follicular hamartomas are associated with endocrine diseases
False with autoimmune disease e.g. alopecia, LE, MG
A pilomatrixoma is a hamartoma of the hair matrix
True main inner root sheath or matrix tumour
Pilomatrixoma accounts for 60% of hair follicle tumours
False 20% most common hair follicle related tumour
Pilomatrixoma occurs in children and young adults affecting both sexes equally
False F>M otherwise true
Pilomatrixoma is associated with Rubenstein-Taybi and Turners syndromes
True also; Gardner’s syndrome and variant MYH-associated polyposis (MAP syndrome) Myotonic dystrophy
Pilomatrixoma is a hard, 3-30mm subcutaneous lesion on the head, neck or arms
True
Pilomatrixoma should be completely excised as malignant change is common
False Malignancy rare but can recur if not completely excised Pilomatrocarcinoma tends to occur in older people (>70) who have long-standing lesions
A fibrofolliculoma is a tumour of the hair follicle mesenchyme (perifollicular connective tissue)
True along with; trichodiscoma perifollicular fibroma
Trichodiscomas occur as multiple small flat-topped papules on the lateral face
False ocur on central face
Familial trichodiscomas is pathognomonic of Birt-Hogg-Dube syndrome
False familial cases can occur other than in BHD
Acrochordons in BHD show differentiation into either fibofolliculoma type or trichodiscoma type
True
Birt-Hogg-Dube syndrome is due to mutation in the hamartin gene
False Folliculin gene FLCN
Fobrofolliculoma is arare lesion with multiple small, poorly-formed pilosebaceous folllicles in a striking fibrous stroma
True
Sebaceous adenoma and sebaceoma are easily disitnguished
False
Sebaceous adenoma and sebaceoma occur in elderly pts on sun damaged skin
False elderly pts but no association with UV damage
Muir-Torre accounts for 1-2% of Lynch syndrome (HNPCC)
True
Sebaceous adenoma and sebaceoma most often occur on the face and scalp and may be sessile, pedunculated or papilliferous
True often yellowish lesions resembling large firm sebaceous hyperplasias esp appear around the eyes
Sebaceous carcinoma accounts for
True
Sebaceous carcinoma mainly occurs in children and young adults
False mainly elderly, also middle age rare reports in children
smoking and UV predispose to Sebaceous carcinoma
False but immunosuppression, arsenic and XRT may be aetiological factors in rare cases
Sebaceomas with high mitotic activity may be wrongly diagnosed as ebaceous carcinoma on histo
True
Sebaceous carcinoma is a slow growing, yellow-orange tumour that favours the eyelids
True usually head and neck esp eyelids but away in Muir-Torre
Sebaceous carcinoma in Muir-Torre usually occur on head and neck sites
False Usually occur away from the normal head and neck sites
Sebaceous carcinoma occuring in the immunosupressed may show microsatellite instability
True Not always Muir-Torre
Sebaceous carcinoma may grow rapidly, invade early and metastasise frequently
False usually slow but can be rapid growth and invasion esp if on eyelid but metastasis very rare
Sebaceous carcinoma can show pagetoid spread on histo
True Often does esp in the more invasive ones around the eye
Mohs can be used for sebaceous carcinoma
True Rx of choice if available other wise complete excision
Apocrine hydrocystoma occurs in men 3x more than women
False M=F, adults any age
Apocrine hydrocystoma is more most common lateral to the lateral canthus
True
Apocrine hydrocystoma has no syndromic associations
False multiple lesions occur in the rare ecotdermal dysplasia Schöpf–Schulz–Passarge syndrome
Apocrine hydrocystoma can occur away from the perioccular region
True reported on axillae, digits and penis
Apocrine hydrocystoma with cytological atypia and mitotic activity and fibrous papillary projections should be designated syringocystadenoma papilliferum
False these are called apocrine cystadenoma should be completely excised
Topical phenol is suitable for multiple apocrine hydrocystomas
False TCA
Syringocystadenoma papilliferum (SCAP) occurs on the face and scalp of young adults
True can also be present at birth or develop in childhood can be asociated with an organoid naevus also reported on vulva, breast, ear, leg
Melanoma can arise in an existing Syringocystadenoma papilliferum (SCAP)
False BCC SCC verrucous carcinoma ductal carcinoma
Apocrine carcinoma arising from Syringocystadenoma papilliferum (SCAP) is a major concern
False exceptionally rare
Hidradenoma papilliferum is an apocrine gland tumour
True Includes; Apocrine hydrocystoma Apocrine tubular adenoma Apocrine carcinoma Syringocystadenoma papilliferum (SCAP) Hidradenoma papilliferum
Hidradenoma papilliferum occurs mainly in the anogenital area of young caucasian women
True most commonly on labia majorum
Hidradenoma papilliferum is 4x more common in the perianal region than the vulva
False 4x more common on the vulva
Hidradenoma papilliferum presents as a 1-40mm mobile lump just below the skin surface, usually in the perineum
True
Apocrine carcinoma is a rare tumour with similarities to breast carcinoma
True may be posiitve for Oe, Prog and androgen receptors grading follows same system as breast carcinoma
Eccrine hydrocystoma occurs aorund the eyes but is much rare than apocrine hydrocystoma
True
The presence of decapiation secretion cannot distinguish apocrine hydrocystoma from eccrine hydrocystoma
False The presence of decapiation secretion is the key differentiating feature
Hidroacanthoma simplex presents as a pedunculated erythematous lesion
False A verucous plaque with a warty brown surface mimicking seb K
Hidroacanthoma simplex affects the limbs more than other sites
True
Hidroacanthoma simplex is composed of largish lobules of blue cells hanging down from epi
True looks like seb k without pseudo horn cysts or other features
All poromas are eccrine
False this is the old view but some lesions may show apocrine differentiation
The acrosyringium is the epithelium of the eccrine ducts
True
The poroma group of eccrine tumours arise from the acrosyringium and dermal eccrine ducts
True Poroma group includes; Hidroacanthoma simplex - acrosyringium Eccrine poroma - acrosyringium Eccrine hydrocystoma - ductal Dermal duct tumour - ductal NB can see apocrine differentiation in these tumours as the ducts of apocrine and eccrine glands are identical
Eccrine poromas can occur anywhere but are commonly seen on the palms and soles
True
Eccrine poromas is a skin coloured papule
False moist, red-pink papule resembles melanoma, BCC or SCC can be pigmented
Eccrine poromas can arise after XRT
True rare reports though
Porocarcinoma can rarely arise from eccrine poroma
True malignnat change well recognised
Eccrine dermal duct tumour is a tumour of the ducts arising in the papillary dermis
True
Syringomas occur equally in males and females
False more common in females
Syringomas are uusually multiple and bilateral with onset is at adolesence
True sufferers often develop more lesions in adult life
Syringomas are associated with Turner’s syndrome
False Downs syndrome No familial type
Syringomas often occur on the cheeks and eyelids but can be elsewehere
True also chest, neck eruptive syringomas tend to appear on chest, neck, abdo and pubic area or buttocks (less commonly)
Laser is Rx of choice for Syringomas
False can use ablative laser but respond wel to diathermy
Hidradenoma can show eccrine or apocrine differentiation
True
Hidradenoma is a solitary tumour more common in women and often on face or upper body
True
Hidradenoma mesures 2-6cm
False 0.5-3cm
Cylindroma is also called Turban tumour or Spiegler’s tumour
True
Spiradenoma is also called Brooke’s tumour
False Trichoepithelioma is also called Brooke’s tumour
Cylindromas can be inherited in a dominant fasion
True
AD cylindromatosis, AD trichoepitheliomas and Brooke-Spiegler are phenotypic variants of the same genetic disease
True all due to mutation in cylindromatosis CYLD gene
Cylindromas occur mainly on the scalp and nearby skin but 25% occur on the trunk and limbs
False
Trichilemmal cyst is the main clinical DD for cyclindroma
True as both prefer scalp esp when multiple present
Spiradenoma and cylindroma can overlap esp in Brooke-Spiegler and both commonly have apocrine diff
True
Spiradenomas are painless, firm, bluish dermal nodules 3-5cm in diameter
False painfull - otherwise all true Called eccrine spiradenoma in Blue ANGEL mnemonic but the eccrine is usually dropped these days
Ischaemic necrosis in a spiradenoma can obscure the histological features
True
Mixed tumour of the skin is an eccrine tumour
False Mixed tumour of the skin (chondroid syringoma) is derived from folliculosebaceous and apocrine structures
Mixed tumour of the skin occurs in middle aged men and usualy measures up to 5mm
False can measure 5-10cm middle aged men, manly on head and neck
Merkel cells are a feature of follicular differentiation
True
Malignant tumours of skin appendages are in general not aggressive and local recurrence is more common than metastasis
True esp if incompletely excised WLE is usually Rx of choice. Staging is important as mets can occur
Malignant chondroid syringoma is the most common example of malignant change in a pre-existing benign sweat gland tumour
False it is Porocarcinoma arising from eccrine poroma
Porocarcinoma (malignant eccrine poroma) usually arises from an existing benign eccrine poroma
False only 18% do. Most are de novo malignnat lesions
Porocarcinoma is relatively common, accounting for up to 0.01% of all skin malignancies
True
Porocarcinoma occurs mainly on the legs in elderly people
True women more than men
In porocarcinoma cases, both local recurence and LN mets ocur in almost one 5th of cases each
True and systemic mets in 10% WLE and follow up required
Aggressive digital papillary adenocarcinoma is a rare tumour of the hands and feet with a high risk of local recurrence and mets
True amputation usually recommended
Microcystoc adnexal carcinoma (MAC) is a malignant type of DTE
False MAC is a malignant syringoma
Microcystoc adnexal carcinoma (MAC) affects young adults esp on upper lip or elsewhere in central face
True
Perineural invasion is an important complication of Microcystoc adnexal carcinoma (MAC)
True Mohs recommended
Can differentiate Pilar sheath acanthoms from Dilated pore of Wiener as the follicle opening is small - not large with multiple projections - and the lobules are larger and more rounded
true
Pilomatrxoma is the most comon tumour of the inner root sheath (matrix)
True all others are rare and not covered in detail in most books
Mucinous carcinoma is a rare deep tumour of the head and neck which resembles mucinous carcinoma of the salivary gland
False resembles mucinous carcinoma of the breast or GIT otherwise all true
Paget’s disease of the nipple is most common in women in their 60s and 70s
False 40s and 50s most common (5th and 6th decades) rare before age 30. Rarely seen in men (worse prognosis) mainly in caucasians
For Paget’s disease with no evidence of underlying breast cancer, breast conserving surgery is a good option
True (although this is rare) with or without XRT where there is underlying cancer treat as usually appropriate Must always completely excise nipple-areola complex
Clinically Pagets’s disease can resemble psoriasis of the nipple, IEC or erosive adenomatosis
True Rarely looks like eczema/ contact dermatitis which is usually bilateral
The main histological DD for Paget’s (nipple) is SCC
False Its melanoma
Paget’s disease of the nipple is positive for CEA, EMA, CAM 5.2 and negative for S100
False positive for CEA, EMA, CAM 5.2 and usually positive for S100
Paget’s disease is thought to originate in the intraduct carcinoma of the breast that frequently accompanies the condition
True This is the epidermotropic theory The alternative theory is that Paget’s cells are a type of transformed malignant keratinocyte
Paget’s disease accounts for fewer than 1% of breast cancers
False fewer than 3%
>90% of paget’s disease (nipple) is associated with in situ or invasive ductal carcinoma
True
A subjacent or distal mass can be clinically palpated in
False Up to 50%
Paget’s cells do not establish intercellular bridges with the adjacent normal keratinocytes but appear both as individual cells in Pagetoid pattern and in nest-like clusters
True
The cytoplasm of Pagets cells stains with PAS and is diastase labile
False PAS positive and diastase resistant due to neutral polysaccharides
Paget’s cells are round with a large round hyperchromatic nucleas and thin rim of clear cytoplasm
True
S100 is helpful in disitnguishing Paget’s disease from melanoma
False both S100 positive Melan A may be helpful
CD23 is positive in both mammary and extra-mammary Pagets disease
True
Extra mammary Paget’s disease (EMPD) is a type of intraepithelial adenocarcinoma
True
Extra mammary Paget’s disease (EMPD) accounts for 20% of Paget’s disease
False 6.5%
Extra mammary Paget’s disease (EMPD) accounst for 6.5% of vulval malignancies
False 1-5%
EMPD is most common on the vulva in women and perianal region in men
True Rare reports of; Axilla, buttocks, thighs, eyelids, external auditory canal (‘ectopic EMPD’ if non apocrine sites)
EMPD is more common in women worldwide
False in Japan it is more common in men
EMPD has a later average age of onset than mammary Paget’s
True 50-80, peak at 65 Mammary peak age is 57
Primary EMPD arises from the epidermis with no associated neoplasm and account for 2/3-3/4 of cases
True
Secondary EMPD arises either from an underlying cutaneous adnexal carcinoma (most often) or an internal maligancy
True Visceral malignancy usually has a contiguous epithelium with the affected site
About 10% of all EMPD cases are secondary to an internal malignancy
True
Perianal EMPD has a 10x higher risk than vulval or penoscrotal disease for having a visceral malignancy associated
False 5x higher risk
Pruritus is uncommon in EMPD
False common and may be intractable often is presenting symptom
In EMPD the vulval area is most commonly afected in women and the scrotum most common in men
False vulva most common in women, perianal most common in men
Elevated serum CEA is a marker of poor prognosis in EMPD
True
Unlike mammary Pagets, EMPD is usually negative for S100
True
Wide local excision and a hunt for visceral neoplasms are the mainstay of Rx for EMPD
True XRT for cases where surgery in appropriate or refused
Local recurrence rates are high for EMPD
Yes often related to incomplete excision
Inguinal LN involvement in EMPD with an underlying skin neoplasm portends a poor prognosis
True zero 5 year survival
A Merkel cell carcinoma is a primary neuroendocrine carcinoma of the skin
True
Merkel cell carcinoma is a rare tumour occuring in elderly people
True
Merkel cell carcinoma occurs more often in sun exposed sites in pts with dark skin types
False sun exposed skin mainly occurs in caucasians - rare in dark skin
Merkel cell polyoma virus is unrelated to Merkel cell carcinoma
False Merkel cell polyoma virus thought to play an aetiological role in MCC
Merkel cell carcinoma is a rapidly growing, red-blue nodule up to 2cm in diameter
True
Immunosuppression may play a role in the deveopment of Merkel cell carcinoma
True
Mitotic figures and apoptotic cells are rare in Merkel cell carcinoma
False abundant
Merkel cell carcinoma cells have dark blue hyperchromatic basophilic nuceli and scanty cytoplasm
True
Merkel cell carcinoma cells demonstrate moulding of nuceli and paranuclear dot posiitvyt on staining with CAM 5.2 or CK7
False CK20 and CAM 5.2 (low MolWt keratin markers) all else true
Other than Merkel cell carcinoma the only other neuroednocrine tumour posiitve for CK20 is neuroendocrine carcinoma of the salivary glands
True
What are poor prognostic histo features for Merkel cell carcinoma?
5HED tumour 5mm or larger Heavy mononuclear inflammatory cell infiltrate Extension into subcutis Diffuse growth pattern
Metastasis are a late feature of Merkel cell carcinoma
False aggressive - mets occur early
30-50% of pts with Merkel cell carcinoma die from metastases
True
Pts with Merkel cell carcinoma should undergo staging including SLNB with CK20 IHC
True
Merkel cell carcinoma is treated with WLE + XRT and lymphadenctomy if SLNB +ve
True
Merkel cell carcinoma is sensitive to chemotherpay but not radiotherapy
False Radiosensitive but not sensitive to chemo
What are the clinical features of Merkel cell carcinoma?
AEIOU Asymptomatic (non-tender) Expanding rapidly (