Fibrous and Fibrohistiocytic Flashcards
(87 cards)
1
Q
What are two dz’s a/w acrochordons?
A
Birt-Hogg-Dube and Cowden
2
Q
What is the clinical presentation of angiofibroma?
A
Most common on the nose can occur on the glans penis
3
Q
What is the histology of angiofibroma?
A
Stellate fibroblasts, collegen, and dialated vessels
4
Q
What are the atypical types of DF?
A
Cellular, hemosiderotic, lipidized/xanthomatous, aneurysmal, DF w/ monster cells
5
Q
What immunohistologic stains can help differentiate DF from DFSP?
A
Factor 13a+, stomelysin-3+, D2-40 +, CD34- (opposite in DFSP)
6
Q
What disease are associated with multiple eruptive DF’s?
A
Lupus, sarcoid, atopic derm, immunosuppression (HAART initiation) leukemia, arise at sites of arthropod assault
7
Q
What is the DDx for collagen trapping see on histology?
A
DF, GA, KS, angiofibroma, blue nevus
8
Q
What disease is sclerotic fibroma is a/w?
A
Cowden’s dz
9
Q
What is the histology of the sclerotic fibroma?
A
It classically has a plywood look, lots of collagen in a storiform pattern
10
Q
What is the clinical presentation of multinucleate cell angiohistocytoma?
A
Red, grouped, smooth papules that often occur on the dorsum of the hand
11
Q
What IHC stain is + in dermatomyofibroma?
A
SMA +, can help distinguish this entity
12
Q
What is the most common tumor of the hand?
A
Giant cell tumor of the tendon sheath
13
Q
What are syndromes associated with connective tissue nevus?
A
Proteus, Buschke-Ollendorf, and tuberous sclerosis
14
Q
What is a syndrome that knuckle pads can be found in?
A
Bart-Pumphrey
15
Q
What findings are seen in Bart Pumphrey syndrome?
A
Leukonychia, hearing loss, knuckle pads, palmoplantar keratoderma
16
Q
What is the SLAM ddx?
A
SCC (spindle cell varient CK903 and CK5/6, p63, p40); leiomysoarcoma (desmin+ and SMA+), AFX, melanoma (s100+ sox10+)
17
Q
What is Bednar tumor?
A
DFSP on Black pt’s on the shoulder
18
Q
DFSP are associated with what mutation?
A
t(17;22) COL1A1-PDGFB
This is why you can use imatinib to treat these
19
Q
What anti-neoplastic medications can you tx DFSP with?
A
Imatinib (because of the translocation)
20
Q
What tumors are CD34+?
A
Benign: sclerotic fibroma, medallion DF (kids), tricholemoma, desmoplastic tricholemoma, trichodiscoma/fibrofolliculoma
Malignant: DFSP, NSF (morphea is CD34-)
21
Q
What is the name of the pediatric version of DFSP?
A
Giant cell fibroblastoma (pseudovascular spaces surrounded by giant cells)
22
Q
What are pearly penile papules?
A
Pearly, white, dome-shaped closely aggregated small papules located on the glans penis. They tend to be multi-layered and circumferential around the corona.
23
Q
What is the most common location for angiofibroma?
A
Nose
24
Q
What conditions are associated with multiple facial angiofibroma?
A
Tuberous sclerosis, multiple endocrine neoplasia type 1, Birt-hogg-dubé syndrome, and rarely neurofibromatosis type 2
25
What is the histology of angiofibroma?
Dome-shaped lesions composed of a dermal proliferation of plump or stellate fibroblasts in a collagenous stroma with an increase in the number of thin-walled, dilated blood vessels
26
Most common location for DF's?
Lower extremities
27
What are the main variants of DF?
1. Cellular DF: increased cellularity, cells arranged in longer fascicles; most common type to be confused w/ DFSP
2. Hemosiderotic: prominent hemosiderin and small blood vessels
3. Lipidized/xanthomatous: prominent foam cells
4. Aneurysmal: large cavernous vascular spaces; clinically worrisome for melanoma or malignant vascular lesion
5. DF w/ monster cells: contains large, bizarre, and highly pleomorphic cells; **mitoses are rare never see atypical mitoses**
28
How do you distinguish between DF and DFSP histologically/IHC?
DF: Factor 13a, stromelysin-3, D2-40 + ; CD34-; Does not invade the subq
DFSP: Factor 13a - stomelysin-3 -, D2-40 - ; CD34 +; invades fat
29
What is the histology of DF?
The nodular proliferation of spindled fibroblasts and histiocytes in the reticular dermis, often with a grenz zone, with hyperplasia and hyperpigmentation of the overlying epidermis.
The fibrosis has a whorled/curly Q pattern, peripheral collagen trapping, admixed inflammatory cells, Touton-type giant cells that may contain hemosiderin, overlying epidermal hyperplasia (tabled rete), basal hyperpigmentation adn folliculsebaceous induction, frequently abuts but never deeply infiltrates fat
30
most common site for superificial acral fibromyxoma?
acral sites, 66% on the nail bed.
31
What is the histology of a superficial acral fibromyxoma?
The lesion is composed of spindled and stellate cells arranged in a loose storiform pattern with a myxoid collagenous matrix. In the epidermis you can see hyperkeratosis/epidermal acanthosis w/ dermal collagen fibers oriented perpendicular to skin surface. **Lacks nerves**
32
How can you tell a supernumerary digit from a superficial acral fibromyxoma from a periungual fibroma?
Supernumerary digit: abundant nerve fascicles
Superficial acral fibromyxoma: no nerves; periungual fibroma: more vascular than SAF
33
What is the clinical appearance of sclerotic fibroma?
Present on the skin or mucous membranes as pearly papules or nodules that measure a few mm to 1-2 cm in diameter.
34
What is the histology of a pleomorphic fibroma of the skin?
Delicately interwoven collagen bundles with a few interspersed large mononucleated and multinucleated atypical fibroblasts. **Stroma is dominated by mesenchymal mucin**. No mitoses
35
What is the histology of multinucleate cell angiohistiocytoma?
Within the dermis is a vascular and collagenous proliferative lesion with conspicuous multinucleate giant cells
36
What is the clinical presentation of dermatomyofibroma?
Well-circumscribed, oval or annular, skin-colored to red-brown plaques measuring 1-2cm, on young women, most common in the shoulder area, axilla, upper arm, and neck.
37
How do you differentiate dermatomyofibroma from DF, NF, pilar leiomyoma, DFSP, and keloid?
The tumor is derived from myofibroblasts so: SMA+ (tram-track), CD34- (distiguishes from plaque-type DFSP), S100 - (distinguishes from NF), factor 13a - (vs DF), and desmin - (vs pilar leiomyoma)
38
What is the histology of the dermatomyofibroma?
The reticular dermis has long fascicles of spindled myofibroblasts arrayed parallel to the skin surface; respects adnexal structures (vs ablated in DF)
39
What is the most common tumor on the hand?
Giant cell tumor of the tendon sheath
40
What is the histology of the giant cell tumor of the tendon sheath?
Giant cell tumor of tendon sheath: the nodular proliferation of round polygonal cells and **osteoclastic giant cells;** variable collagen inflammatory and hemosiderin in the background.
## Footnote
**\*\*high yield\*\* This is the only testable neoplasm w/ numerous osteoclastic giant cells.**
41
What is fibroma of tendon sheath?
Some authors believe this tumor may represent a sclerotic end-stage of a giant cell tumor of the tendon sheath. Frequently found on hands, feet, and thumb.
42
Clinical progression of nodular fascitis?
Rapidly growing but self-limited subcutaneous nodule measuring 1-5 cm. May be triggered by trauma. it is a benign reactive process in young to middle-aged adults.
MC location is on the upper extremity. In children, the head and neck is the most common location.
43
What is the histology of nodular fasciitis?
Prototypical "pseudosarcoma" because of its increased cellularity (comprised of spindle cells) and frequent mitoses.
Clues: myxoid stroma, sharp circumscription, lack of atypical mitoses, and RBC extravasation. The fibroblasts are arranged in a haphazard array that looks "tissue culture-like"
## Footnote
*this histology is often tested because it is classic*
44
What is the clinical progression of a connective tissue nevus?
Firm, solitary or multiple, skin-colored papules, nodules, or plaques that usually present at birth or arise during childhood.
Represent hamartomas rather than neoplasms
45
What are the different variants of connective tissue nevus and what syndromes are they associated with?
Cerebriform appearance: m/c on the plantar surface but can be seen on hands and or others. A/w Proteus syndrome
Multiple skin-colored or slightly yellowish papules: called **dermatofibromas lenticularis disseminata.** A/w Buschke-Ollendorf syndrome. AD LEMD3, osteopoikilosis (celery bones).
Shagreen patch-pebbly plaque with a "pigskin" appearance on **lower back**. A/w tuberous sclerosis
46
Two histopathologic features of connective tissue nevus?
Collagenoma: haphazard thickened collagen bundles
Elastoma: increased elastic fibers; histologic changes may be very subtle need VVG stain
47
What is the clinical presentation of infantile digital fibroma?
**These lesions tend to spare the thumb and great toe.** Spontaneous regression is seen after 2-3 years but contractures and functional impairment can occur so conservative excision vs obs is recommended.
Presents as reddish-pink firm nodules that are typically 1-2 cm in size. Occur on dorsal or lateral aspects of the distal phalanges of both fingers and toes
48
What is the clinical presentation of infantile myofibromatosis?
Infantile myofibromatosis: 50% @ birth; multiple pink-violaceous dermal/SQ nodules on the head;
## Footnote
It can involve bones and internal organs (increased morbidity and mortality).
49
What predicts poor outcomes for infantile myofibromatosis?
Visceral involvement
50
What is the clinical presentation of a calcifying aponeurotic fibroma?
Mostly on the hands and feet of young children. The nodule is usually fixed to underlying structures. These tumors are benign and commonly recur after excision **(50%)**
51
What is the clinical presentation of a fibrous hamartoma of infancy?
Painless, solitary, skin-colored, subcutaneous nodule
It favors the axilla, shoulder, and upper arm, although it can appear in other sites such as the groin. Tx can be excision. Otherwise, it will continue to grow and stabilize by mid-childhood.
52
What are the 5 types of superficial fascial fibromatoses?
Plamar fibromatosis (dupuytren dz)
Plantar fibromatosis (ledderhose dz)
Penile fibromatosis (Peyronie Dz)
Knuckle pads (holoderma)
Pachydermodactyly
53
What syndrome can deep desmoid tumors be a/w?
Gardner's syndrome: they have beta-catenin mutations and state B-catenin +
54
Clinical presentation of palmar and plantar fibromatosis?
Appears during adulthood and incidence increases w/ age. Flexion contractures, especially of the 4th and 5th fingers can result
55
What is the clinical presentation of penile fibromatosis?
Peyronie's dz: more common in middle-aged to elderly men; pain and erectile dysfunction are common
56
What is the clinical presentation of knuckle pads?
Tend to affect the extensor surfaces of interphalangeal and metacarpophalangeal joints
## Footnote
May be a/w palmar, plantar fibromatosis. can be from trauma or idiopathic.
57
What syndrome can be associated with knuckle pads and what are the other associated sx's?
Bart-Pumphrey Syndrome: Knuckle pads are seen, a/w palmoplantar keratoderma, hearing loss, and leukonychia.
58
Clinical of Pachydermodactyly?
Digital fibromatosis. Adolescent boys with soft tissue swelling of the lateral aspects of the proximal interphalangeal joints of the second to 4th fingers. Can be related to mechanical trauma
59
What cytogenetic abnormalities may be a/w desmoid tumors?
Trisomies of chromosomes 8 and 14
60
Clinical of plexiform fibrohistiocytic tumor?
Slow growing, firm, painless mass in child or young adult. \<3cm in diameter and favors the **wrists and hands**. Striking female predominance. Intermediate malignancy, tendency to recur locally but not metastasize.
61
What type of treatment and follow-up is needed for plexiform fibrohystiocytic tumor
Locally aggressive tumor w/ high rates of recurrence. Needs wide excision and wide margins with **LONG-TERM EVAL TO MONITOR FOR REGIONAL OR SYSTEMIC METS.**
62
Where are atypical fibroxanthomas most commonly seen?
Sun-damaged skin of the head and neck in elderly patients.
63
What is the clinical presentation of AFX?
Rapidly growing, dome-shaped nodule measures 1-2 cm. Often has serosanguineous crusts and ulceration
64
Tx and follow-up for atypical fibroxanthoma?
Low-grade sarcoma, recurs in 5% of cases. Almost never metastasizes. Treatment is Mohs vs WLE.
65
What is the histology of an atypical fibrous xanthoma (AFX)?
Fairly well-circumscribed, an overtly malignant dermal proliferation that is **SLAMMED** up against an atrophic/ulcerated epidermis; tumor extends down to deep dermis in a pushing fashion. 4 main cell types in the tumor: spindle cells, histiocyte-like cells, xanthomatous cells, and bizarre multinucleated giant cells. all cell types have hyperchromatic nuclei, pleomorphism, and high mitotic rate w/ numerous wildly atypical mitoses.
66
What is the SLAM ddx?
SCC, Leiomyosarcoma, AFX, Melanoma
## Footnote
*note: Other items on the SLAM DDx need to be r/o before going with AFX*
67
Clinical presentation of a DFSP?
Young to middle-aged adults, predilection for the shoulder or pelvic region.
Presents as slow-growing, asymptomatic, skin-colored indurated plaque that eventually develops violaceous to red-brown nodules.
## Footnote
*nodules are firm and attached to the subcutaneous tissue.*
68
What is the characteristic genetic abnormality in DFSP?
t(17;22) COL1A1-PDGFB fusion
69
Treatment for DFSP
Mohs\>WLE w/ 2cm margins, Imatinib is approved for unresectable or metastatic dz w/ a 46% response rate. It blocks the function fo the COL1A1-PDGFB fusion protein
70
What is the histology of a DFSP?
Bland fibrous tissue that extends to the deep dermis and envelopes fat (honey-combing). Looks less atypical than an AFX, but is worse. Has a classic "storiform" arrangement of the spindle cells/fibrosis
71
What are some clinical differences between DFSP and DF?
DF: Favors arms/legs, static, well-defined firm papule generally \<1cm (may be pink in fitz 1 pts).
DFSP: expanding keloidal **plaque w/ nodules, red-blue in color.**
72
What benign tumors are CD34+?
Sclerotic fibroma, Medallion DF, Tricholemomma, Desmoplastic tricholemomma, trichodiscoma/fibrofolliculoma
73
What malignant tumors are CD34+?
DFSP, Nephrogenic Systemic Fibrosis
74
What is a giant cell fibroblastoma?
It is like a pediatric variant of DFSP pediatric variant. Same COL1A1-PDGFB translocation.
Favors head/neck, trunk, and groin. Looks like DFSP but has pseudovascular spaces surrounded by giant cells
Irregular “angiectoid” or pseudovascular spaces lined by multinucleated giant cells are present throughout the tumor\*
75
What is the clinical presentation of fibrosarcoma?
Middle-aged adults, most common location is the lower extremities followed by upper extremities, trunk, and head and neck. Slow-growing usually dx as large palpable painful nodule. Can appear in areas of old burn scars or radiation.
76
What is the tx for fibrosarcoma?
WLE, may need adjuvant RT and amputation. In high-grade sarcomas systemic chemo is given. Hematogenous mets to the lung m/c followed by bones.
77
What is the histologic presentation of fibrosarcoma?
Classic appearance with cellular fascicles of atypical spindle-shaped fibroblasts w/ coarse nuclear chromatin arranged in a "herringbone" pattern.
78
What is the clinical presentation of epithelioid sarcoma?
Rare, slow-growing firm subq nodule of **distal** extremities usually hands and fingers. Pt's are usually between 20-40 y/o age. M\>F (2x)
79
What are the two clinicopathologic subtypes of epitheloid sarcoma?
Conventional classic (distal) form: a proclivity for distal sites and pseudogranulomatous growth pattern.
Proximal type ("large cell") usually arises more proximally or on the trunk. Is composed of nests and sheets of large epitheloid cells.
80
What is the histology of epithelioid sarcoma?
Epithelioid sarcoma: large epithelioid tumor cells w/ ample cytoplasm may imitate a granulomatous or epithelial growth pattern. Nuclei in these cells are INI1-negative.
81
From what structure does the neurofibroma come from?
The entire peripheral nerve
82
What is the clinical presentation for neurofibroma?
M/c on head/trunk. Soft lesion w/ buttonhole sign. Can be pruritic and can be associated w/ NF-2
83
What are 4 rapidly growing cutaneous tumors of the head and neck that can be seen on the elderly?
AFX, pleomorphic dermal sarcoma, melanoma, Merkel cell carcinoma
84
What is the difference between atypical fibrous xanthoma (AFX) and pleomorphic dermal sarcoma?
You need a deep bx so you can see the criteria for pleomorphic dermal sarcoma
1. subcutaneous involvement
2. perineural involvement and lymphovascular invasion
85
What is the histology of the infantile digital fibroma?
Myofibroblasts have pathognomonic cytoplasmic eosinophilic hyaline globules (inclusion body fibromatosis). Spindled myofibroblasts, collagenous stroma, intracytoplasmic eosinophilic inclusion bodies
86
What is the histology of a calcifying aponeurotic fibroma?
An irregular infiltrative mass of fibroblastic tissue is present in the subcutaneous fat. There is prominent calcification present
87
What is the histology of a fibrous hamartoma of infancy?
Triphasic pathology: plump spindle cells in fascicles a/w collagenous stroma, small aggregates of immature mesenchymal cells, and mature fat.
