Chapter 66 Dermal Hypertrophies and Benign Fibroblastic/Myofibroblastic Tumors Flashcards
predisposition to keloids in darker skin and reports of a familial, autosomal _____ inheritance suggest genetic influences.
dominant
There also is an apparent association with melanin pigment, as albino and vitiliginous skin form keloids. T/F ?
F
do not
Histopathologically, ____ are composed of thick, haphazard, eosinophilic, collagen bundles
keloids
______ are more cellular with myo bro- blasts either in disorganized whorls or sometimes oriented parallel to the epidermis
Hypertrophic scars
Hypertrophic scars are associated with HLA-_____
DRB16
Keloids express increased levels of the ____ protein, an oncogene product also present in neoplasms such as basal cell carcinoma
gli-1 protein
______ (a collagenase inhibitor usually not present in normal scars) may contribute to increased collagen deposits
α1-Globulin
Hypertrophic scars have decreased levels of the profibrotic agent ______
tumor necrosis factor
_____ treatment reduces TGF-β1 levels in keloids
Carbon dioxide laser
Dermato broma is a common, benign tumor that has a predilection for the _______
lower legs of women
Histologically, the epidermis is usually hyperplastic and hyperpigmented.
There may be follicular or sebaceous induction.
The dermis has fascicles or haphazardly arranged collections of spindle cells that lack atypia in most cases of ______
dermatofibroma
edges of the lesion are poorly defined with individual cells hugging collagen bundles (“collagen entrapment”)
Dermatofibromas are generally factor ____ and CD ____
XIIIa-positive and CD34−
features of ATYPICAL, CELLULAR, DEEP, AND INDETERMINATE FIBROUS HISTIOCYTOMAS
Clinical Features Often >2 cm in size Sometimes facial Any age, but some predilection for young adults Often recur after incomplete excision Rare potential for metastasis
Histologic Features
Background of dermatofibroma/fibrous histiocytoma
Variable areas of atypical cells, high cellularity
May extend deeply into subcutaneous, sometimes in a honeycomb pattern
May stain with CD34
Histologically, ______ is a polypoid lesion with a central collagenous core. Adnexal structures are generally absent.
an acrochordon (fibroepithelial polyp, soft fibroma)
Histologically, the dermis shows fibrosis with stellate fibroblasts and dilated vessels.
fibrous papules (angiofibroma)
Identical histology is seen in pearly penile papules and periungual fibromas (Koenen’s tumors)
2- to 4-mm, dome-shaped, yellowish to skin-colored papules located on the head, neck, and upper trunk; multiple lesions may be associated with Birt–Hogg–Dubé syndrome
fibrofolliculoma/trichodiscoma
Histologically, _______ show a normal epidermis overlying collagen in the lower dermis. The collagen may be subtly increased, thickened, or oriented vertically to the epidermis, and muscin may be increased. Elastic fibers may also be increased.
connective tissue nevi
Familial cutaneous collagenoma is an autosomal dominantly inherited condition of multiple, often papular connective tissue nevi usually appearing postpuberty on the trunk and upper extremities
pro- gressive cardiomyopathy.
Mutations have been found in the adenomatous polyposis coli (APC) gene (5q21)
desmoid tumor (aggressive fibromatosis)
Tumors associated with Gardner/Familial adenomatous polyposis (FAP) are often intra- abdominal, may be more aggressive and surgically unresectable, and are associated with a 10% mortality
______ presents as a rapidly growing nodule on the head and neck, shoulder/upper arm, or thigh; generally before age 2
Infantile fibromatosis
The lipofibromatosis variant has a predilection for the hands and feet
________ generally presents before age 2, with many cases being congenital.
Multiple nodules involving the skin and other organs (gastrointestinal, kidney, lung, heart) are seen, with mortality approaching 75%
Infantile myofibromatosis
Histologic diagnosis relies on the identification of two separate components—a fascicular myofibroblastic pattern at the periphery with a hemangiopericytoma-like pattern in the center
Histopathologic examination as well as cytogenetic and molecular pathology studies will distinguish ______ (chromosome 8 abnormalities) from ______________ (translocation between chromosomes 12 and 15—ETV6 and NTRK3 genes)
myofibromas
congenital infantile fibrosarcomas
_____________ is a rare benign tumor that presents before age 2 (up to 25% congenital) as a solitary, painless, rapidly growing, flesh-colored, ill-defined, subcutaneous nodule, or plaque. There is a male predominance.
Fibrous hamartoma of infancy
These lesions rarely present with overlying skin changes such as hypertrichosis, alteration in pigmentation, and eccrine
gland hyperplasia
________ is an often self-limiting, rapidly growing tumor, presenting in the first few weeks of life.
benign proliferation of fibroblasts in the lower one-third of the sternocleidomastoid muscle, rarely bilateral, and occasionally associated with torticollis or facial asymmetry
Fibromatosis colli
fine needle aspiration for diagnosis
__________ is a rare form of superficial juvenile fibromatosis presenting as (an) asymptomatic, flesh-colored, firm nodule(s) on the fingers and toes (tending to spare the thumb or hallux)
Infantile digital fibromatosis
The pathognomonic finding is eosinophilic, perinuclear inclusion bodies composed of actin laments, which stain red with Masson trichrome stain and purple with phospho- tungstic acid-hematoxylin