Neoplastic and Non-Neoplastic Tumors Flashcards
Breed Predilections for Papilloma
Cocker Spaniel, Kerry Blue terrier
Breed Predilections for Infundibular keratinizing acanthoma
Collie, GSD, Keeshond, Lhasa paso, Norwegian Elkhound, Old English Sheep dog, Yorkie
Breed Predilections for SCC
Scottie, Pekingese, boxer, poodle, Norwegian elkhound
Breed Predilections for SCC (glabrous, non pigmente)
Dalmatian, bull terrier, Pittbull, beagle
Breed Predilections for SCC (claw bed)
Giant Schnauzer, Black labs, black standard poodles, dachshund, Bouvier de Flandres
Breed Predilections for Feline Benign Basal Cell Tumor
Persian and Himalayans
Breed Predilections for Basal Cell Carcinoma
Cocker Spaniels, English Springer Spaniels, Kerry Blue Terriers, poodles, Shetland Sheep dog, Siberian Huskies, Siamese cat
Breed Predilections for Trichoepithelioma
Cocker Spaniels, English Springer Spaniels, basset hound, GSD, golden retriever, Irish setter, miniature schnauzer, standard poodle, Persian cat
Breed Predilections for Tricholemmoma
Afghan Hound
Breed Predilections for Pilomatrixoma
Kerry Blue, Old English Sheepdog, poodle
Breed Predilections for Trichoblastoma
Cocker Spaniel and Poodle
Breed Predilections for Sebaceous gland tumors
Beagle, Cocker Spaniels, dachshunds, Irish Setters, llhasa apse, malamute, miniature schnauzer, poodle, Shih Tzu, Siberian husky, Persian cat
Breed Predilections for Sweat Gland tumors
Cocker Spaniels, GSD, Golden Retrievers
Breed Predilections for circumanal tumors
Beagle, cocker spaniel, English bulldog, GSD, Lhasa apso, Samoyed, Shih Tzu, Siberian husky, Afghan hound, dachshund.
Breed Predilections for Fibroma
Boston terrier, Boxer, Doberman, fox terrier, golden retriever
Breed Predilections for Fibropruritic nodule
GSD
Breed Predilections for Myxoma or myxosarcoma
Doberman pinscher, GSD
Breed Predilections for Schwannoma
Fox Terrier
Breed Predilections for Hemangioma
Airdale, Boxer, English Springer Spaniel, German Shepherd, golden retriever,
Breed Predilections for Hemangioma (glabrous-actinic) and Hemangiosarcoma (glabrous)
Pitbull, Basset, beagle, Dalmation, English Springer Spaniel, Greyhound, Saluki, Whippet
Breed Predilections for Hemangiosarcoma
Bernese Mountain Dog, GSD, Golden Retriever
Breed Predilections for Hemangiopericytoma
Beagle, boxer, cocker spaniel, collie, fox terrier, English Springer spaniel, GSD, Irish Setter, Siberian Husky
Breed Predilections for Lipoma
Cocker spaniel, dachshund, Doberman puncher, Labrador retreiver, miniature schnauzer, Weimaraner, Siamese cat
Breed Predilections for Liposarcoma
Brittany Spaniel, Dachshund, Shetland Sheep dog
Breed Predilections for MCT
Pittbulls, Boston Terriers, bull terrier, dachsund, English bulldog, fox terrier, golden retriever Labrador retriever, pig, Shar Pei, Weimaraner, Siamese cat
Breed Predilections for Lymphoma
Basset hound, boxer, cocker spaniel, GSD, golden retriever, Irish setter, Scottish terrier, St. Bernard
Breed Predilections for Plasmacytoma
Cocker Spaniel
Breed Predilections for Histiocytoma
Pittbulls, Boston Terriers, Boxer, Cocker Spaniel, dachshund, Doberman punchers, Enlglish springer spaniel, Grat Dane, Labrador retriever, miniature schnauzer, rottweiler, Scottish terrier, Shar Pei, Shetland sheepdog, Westie
Breed Predilections for Malignant Histiocytosis
Bernese Mountain Dog
Breed Predilections for Systemic histiocytosis
Bernese Mountain Dog
Breed Predilections for Cutaneous histiocytosis
Collie, Shetland Sheep Dog
Breed Predilections for Benign Fibrous histiocytoma
Collie, golden retriever
Breed Predilections for Melanocytic tumors
Airedale, Boston terrier, boxer, Chihuahua, chow chow, cocker spaniel, Doberman, English Springer spaniel, golden retriever, Irish setter, Irish terrier, miniature schnauzer, Scottish terrier
Breed Predilections for Follicular cysts
Boxer, Doberman pinchers, miniature schnauzer, Shih Tzu
Breed Predilections for Dermoid Cysts
Boxer, Kerry Blue Terrier, Rhodesian ridgeback
Breed Predilections for Collagenous nevus
German Shepherd
Breed Predilections for Vascular Nevus (scrotal)
Airedale terrier, kerry blue terrier, Labs, Scottie
Breed Predilections for Epidmermal Nevus
Miniature Schnauzer, Pug
Breed Predilections for Calcinosis Circumscripta
Boston Terrier, boxer, GSD
Breed Predilections for Focal mucinosis
Doberman, Shar Pei
Which breeds have the highest rate of cutaneous neoplasms in dogs and cats?
Boxers, Scotties, Bullmastiffs, basset hounds, Weimeraners, Kerry Blue Terriers and Norwegian Elkhounds
Siamese and Persian
What viruses are non enveloped DNA viruses which are transmitted by direct and indirect (via fomites) contact and specially infect epithelial cells. In general, infections of this virus occurs at the site of damaged skin or mucous membranes, with viral incubation varying from 1 to 2 months.
Papillomaviruses
In dogs, at least ___ subtypes of papillomaviruses have been identified, demonstrating hot tissue specificity.
7
_____ hybridization is highly sensitive and specific , but time consuming and does not allow for detection od DNA segments of unknown papilloma types.
Southern Blot
______ is less sensitive than southern blot, but does allow identification of cells harboring viral DNA.
In Situ Hybridization
____ is the method most often used to to identify pappilomavirus in tissue. While its fast and simple, it is not considered as sensitive for the reliable identification of viral DNA.
PCR
What virus is fairly stable int he environmental and can survive for 63 dats at 4 to 8C. Humoral immunity protects against viral challenge but does not play a role in clearance of established lesions.
Papillomavirus
_______ immunity is of key important in papillomavirus regression, and infiltration with CD4 and CD8 T lymphocytes is necessary for viral clearance.
Cellular immunity
Live or formalin-inactivated ______ vaccines are effective preventatives but do not possess therapeutic activity for eat treatment of established infections.
canine papillomavirus
Viral genomic nomenclature is dictated by the separation of viral genes into what 3 discrete segments?
L (late genes)
E (early genes)
LCR (long control region)
The ____ and ____ genes encode for viral capsized proteins, while the ___ genes are involved in viral DNA replication.
L1 and L2
E genes
Which early gene segments are true oncogenes capable of immortality cells, including cell growth and promoting chromosomal instability in the host cells?
E6 and E7
What are the 7 roles of the E genes in papillomavirus survival?
E1 - DNA replication
E2 - Transcription activation
E3 - modulating the immune response of infected cells
E4- disruption of cytokeratins facilitating oral release
E5 - interactions with growth factors
E6/7 - immortilization and cell proliferation
Which oncoprotein targets degradation of p53 tumor suppressor protein by the ubiquitin pathway, leading to unblocking of cell division and host DNA synthesis, which predisposes to chromosomal instability and accumulation of various mutations in affected cells?
E6
What is an important tumor suppressor protein that is inhibited when bound by oncoprotein E7?
retinoblastoma (Rb)
Cutaneous papillomas are common in the dog, and at least 5 syndromes are recognized clinically.
Canine oral papillomatosis Cutaneous paillomas Cutaneous inverted papillomas Mutliple pigmented, papular, cutaneous papillomas Multiple pigmented plaques
Florid oral papillomatosis has been seen in beagles in associated with ____ deficiency, and anecdotal in dogs undersign immunosuppressive therapy with CSA.
IgA
Cutaneous papillomas occur occasionally in older dogs and are more common in male does of what two breeds?
Cocker Spaniels and Kerry Blue Terriers
Cutaneous inverted papillomas occur where typically?
Lesions occur commonly on the ventral abdomen and groin, small, raised and firm, and contain a central pore opening to the surface of the skin.
What two breeds commonly develop viral pigmented plaques?
miniature schnauzers and pusgs (and seen in a Shar-Pei)
Lesions often begin at 2 to4 years of age and are most common on the venture and medial thighs. Melanotic macule and plaques become progressively more scaly and hyperkeratotic.
What are the two established types of papillomaviruses in cats?
FdPV-2 (oral) and FdPV-1 (skin)
Histologically, papillomas can be divided into ____ and ____ types.
Squamous and fibrous types
How are squamous papillomas characterized histologically?
papillated or plaque like epidermal hyperplasia and papillomatosis with variable degrees of ballooning degeneration (koilocytosis) and giant, clumped, pleomorphic keratohyaline granules.
Basophilic internuclear inclusion bodies are variable findings.
Inverted papilloma are characterized histologically by what features?
Cup-shaped lesions with a central core of keratin. The cup is lined by mature squamous epithelium with centripetal papillary projections, ballooning degeneration, abnormal keratohyaline granules and variable intranuclear inclusion bodies.
Pigmented papillomas are characterized histologically by what features?
Unique cup-shaped appearance with marked parakeratotic hyperkeratosis, angular basophilic intranuclear inclusion bodies, eosinophilic fibrillar cytoplasmic inclusions and scarce keratohyalin granules.
Live autologous virus vaccines produced from canine oral papillomas are protective but have been associated with the development of what disease?
Injection-site squamous cell carcinomas
Modified papillomavirus vaccines including formalin-inactivated or replication-deficient adenovirus vaccines containing codon-optimized __, __, __ and ___ genes of canine oral papiullomavirus can adored complete protection against natural and experimental infection, and have the added benefit and safety of not inducing injection-site SCC.
E1, E2, E4 and E7
What are uncommon benign neoplasms of the dog, which are believed to arise from the hair follicle. Papillopmavirus infections do not appear to be an underlying cause for the development of these tumors.
Infundibular keratinizing ancanthoma (keratoacanthoma)
Infundibular keratinizing acanthus typically occur in dogs 5 years of age or younger, with male dogs more commonly affected than female. The incidence is higher in purebred dogs and particularly in ____ and ____ breeds.
Norwegian elkhound and keeshond
How are infundibular acanthomas characterized histopathologically?
Infundibular keratinizing acanthomas are characterized by a keratin-filled crypt in the dermis that opens to the skin surface. The wall of the crypt is composed of thick, complex, folded layer of stratified squamous epithelium with columns of squamous cells projecting peripherally from the basal surface of the wall and forming small epithelial nests. (major other differential is an inverted papilloma)
Despite similarities in morphology, infundibular keratinizing acathomas and SCC can be distinguished from one another by which two cell proliferation IHC markers?
Ki-67 and AgNOR
What are common malignant neoplasms of the dog and cat in which the tumor cells show keratinocyte differentiation? It has been associated with chronic sun exposure, lack of pigment and thin hair coat.
SCC
Mutations in the tumor suppressor gene ___, as well as over expression of __ protein, which may be involved in tumor development, have ben identified in both canine and feline SCC.
p53
Which four dog breeds are predisposed to developing SCC?
Keeshon, Standard Schnauzer, basset hound and collie
Approximately, ___ percent of dogs affected by sublingual SCC are large breeds, with 70% having black coats. Breeds at an increased risk include which breed?
75%
Schnauzer, Poodles, Scotties, Labs, Rottweilers and dachshund
____ is the most common neoplasm of the digit.
SCC
In cats, this is rare. The majority of reported cases of Digital carcinomas of the cat have been shown to be metastases from primary pulmonary carcinomas.
White cats of any haricot length have a ___ times greater risk of developing SCC than cats of other colors, owning to their increased susceptibility to actinic damage.
13 times
Over 80% of lesions are found on the head, usually involving the nasal plant, pinnae and eyelids.
SCC stain positive for ____, wand such examinations may be critical is establishing the true identity of poorly differentiated spindle cell tumors.
cytokeratin
Canine Digital SCC has a locally aggressive behavior, with 65% to 80% of dogs showing bony lysis of ____.
the third phalanx
Mutlicenütric Squamous Cell Carcinoma In Situ is characterized by what features histologically?
Well-circumscribed areas of neoplastic keratinocytes affecting the epidermis and follicular epithelium without invasion through the basement membrane into the dermis.
Imiquimod ia an imidazoloquinoline, a family of immunostimulaotry drugs that work via binding to ___ and ____ on macrophages. This in turn leads to both innate and cell-mediated immune responses that result in tissue specific apoptosis.
TLR 7 and 8
What tumor is uncommon benign neoplasms of the cat that is thought to arise from the basal cells of the epidermis. The cause in cats is unknown and does not appear to be actinic induced, because feline basal cell tumors often arise from haired skin.
Benign Feline Basal Cell Tumors
Which breeds of cats may be predisposed to developing basal cell tumors?
Himalayan, Siamese and Persian
Describe basal cell tumors histologically
Characterized by a well-circumscribed, symmetric proliferation of basaxoid cells that has a fairly broad zone of connection to the overlying epidermis. The tumor often has a lima bean-shaped silhouette. The basaxoid cells are arranged in tightly packed lobules and trabeculae and stain positive for cytokeratin.
What tumor is common in cats and uncommon in dogs and is a low-grade malignancy arising from small pluripotential epithelial cells within the basal cell layers of the epidermis and adnexa. These tumors are capable of metastasizing and frequently melanotic.
Basal Cell Carcinomas
What breeds are predisposed to developing basal cell carcinomas?
Siamese cats, cocker spaniels, kerry blue terriers, Shetland sheepdogs, Siberian huskies, English springer spaniels and possible.
Occurring most commonly on the head, neck and thorax
What is a potent angiogenic factor, capable of inducing endothelial cell proliferation, migration and tube formation. This has been evaluated in basal cell carcinomas.
VEGF
What is the most common type of basal cell carcinoma found in dogs characterized by an irregular dermal mass of basaxoid cells with a plaque-like configuration multifocal epidermal continuity and multiple areas of abrupt squamous differentiation.
keratinizing basal cell carcinoma (basosqamous carcinoma)
What is the rare and more commonly encountered type of basal cell carcinoma in cats. The overall architecture is identical to that of a solid basal cell carcinoma, but the epithelial cells are large and polygonal and have water-clear or finely granular cytoplasm.
Clear cell basal cell carcinoma
What are uncommon benign neoplasms of dogs and cats that are thought to arise from keratinocytes that differentiate toward all three segments of the hair follicle?
Trichoepithelioma
Trichoepithelium, there is a predilection for what breed in cats and dogs?
Persians - head/limbs
Goldren Retrievers, basset hounds, GSD, cocker spaniels, Irish setters, Enlighs springer spaniels, miniature schnauzers and standard poodles.
There is a variant showing marked mucinosis that is most common in golden retrievers.
Regarding expression of proteins associated with cell cycling and proliferation, ____ is high in trichoepitheliopomas and ____ is low.
p27 high
Proliferating Cell Nuclear Antigen (PCNA) low
= SLOW growth rate
What are rare benign neoplasms of dogs and cats the arise from keratinocytes of the ORS of hair follicles? Which breed of dog is predisposed?
Tricholemmoma
Afgan hounds
What tumors are rare benign neoplasms dogs that are highly structured hamartomas of the pilosebaceous unit.
Trichofolliculoma
What is an uncommon benign follicular tumor of cats. The cause of the lesion is unknown, although most evidence factors a developmental origin arising from the combined forces of obstruction and intrafollicular pressure leading to hair follicle hyperplasia.
Dilated Pore of Winer
Older cats on neck, head or trunk with ‘wide-mouthed’ pore
What are calcifying epithelium’s that are uncommon in dogs and rare in cats and thought to arise from the hair matrix. Characterized also by low expression of p27.
Pilomatrixoma (Pilomatricoma, calcifying epithelioma)
** Kerry Blue Terriers, Poodles and Old English Sheepdogs are predisposed
Cytologically, what are the key features consistent with a pilomatrichoma?
Presence of basaloid cells along with ghost cells
What are benign neoplasms of dogs and cats, where are presumable derived from primitive hair germ epithelium? Expression of p27 is high and PCNA is low, therefore, there is are slow growing tumors.
Trichoblastoma
- *Cocker Spaniels and Poodles are predisposed
- Base of ear (head)
Trichoblastomas occur in four basic histopatholic subtypes include ribbon, trabecular, granular, and clear. Which type is the most common in dogs? Cats?
The ribbon type is most common in dogs and is characterized by basaxoid cells arranged in branching winding, and radiating columns with nom epidermal contiguity.
The trabecular type is most common in cats and is characterized by lobules and broad trabecular of basaloid cells with prominent peripheral palisading and no epidermal contiguity.
What majority of trichoblastomas will coexpress cytokeratin ___ and ___.
8/18
Nodular sebaceous hyperplasia accounts for about __% of the sebaceous gland tumors and occurs most commonly in beagles, cocker spaniels, poodles, dachunds, and miniature schnauzers.
53%
Which sebaceous gland tumor is a basal cell tumor with sebaceous differentiation? It accounts for about 37% of sebaceous gland tumors and found most commonly on Llasa apsis, Shih Tzus, malmustes, Siberian huskies and Irish Setters.
Sebaceous epitheliomas
Which tumor accounts for about 8% of sebaceous gland tumors and commonly found on eyelids and limbs?
Sebaceous adenomas
This tumor account for only about 2% of the sebaceous gland tumors. The head and limbs are most commonly affected, and cocker spaniels are predisposed.
Sebaceous adenocarcinomas
Epitrichial sweat gland tumors are found most commonly in which breeds?
Golden Retrievers, Cocker Spaniels and GSD
What sweat gland tumor can be malignant or benign and are extremely rare. The lesions are solitary, form, well to poorly circumscribed, frequently ulcerated, and 1 to 3 cm in diameter, they occur on the footpads.
Atrichial sweat gland tumors
Epitrichial sweat gland carcinomas may be more frequent in which cat breed?
Siamese
**Atrichial sweat gland tumors are almosOert always malignant in cats and are extremely rare
Perianal gland tumors have been evaluated for derangements in tumor suppressor proteins, specifically p53 and _____ - identified in many perianal gland tumors, the expression of p52 was predominantly absent fro al lesions regardless of histologic subtype.
Mdm2
Fibroms contain gin focal areas of mutinous of myxomatous degeneration often called ______.
fibromyxomas
What are rare fibrocystic tumors in dogs and cats with no defined cause for their development. German Shepherd dogs may have a genetic predisposition to develop collagenous nevi, which appear similar to dermatofibromas - in associated with renal and uterine tumors.
Dermatofibromas
These are also known as skin tag, keratin tag, skin polyp, acrochordon, fibroepithelial polyp or soft fibroma - an uncommon benign tumor of fibrovascular origin in dogs. Suspected to be a proliferative response to trauma or focal furunculosis.
Fibrovascular papilloma
**Doberman Pinchers and Labs
Fibropruritic nodules are associated with what disease?
chronic self-trauma secondary to flea-bite hypersensitivity
*German Shepherds over dorsum
The cause of this rare neoplasm is possible associated with the presence of papillomavirus involved in tumorigenesis.
Feline Sarcoid
These tumors are common in cats and uncommon in dogs and arise from dermal or subcutaneous fibroblasts. this cause of these tumors I older animals is unknown, but some tumors that arise in young cats are believed to be virally induce via FeSV.
Fibrosarcomas
** FeSV is a mutant of FeLV, and cats with FeSV-induced fibrosarcomas are positive for FeLV.
Dobermans, Cockers and Goldens overrepresented
What are rare neoplasms of the dog and cat that arise from dermal and subcutaneous fibroblasts?
Myxomas and myxosarcomas
**Doberman Pinchers and German Shepherds
What tumor is thought to represent a proliferative inflammatory process arising from the subcutaneous fascia and exhibiting a clinical aggressive behavior that suggests a locally invasive neoplasms? It is rare, benign and non-neoplastic and occurs around the eyes.
Nodular fasciitis
A recent study. using PCR found that a subset of Scwannomas expressed a point mutation of the ____ oncogene, suggesting that this mutation could be a participatory genetic cause and surrogate genetic marker for identity malignancy.
HER2/neu
** IN most dogs, this tumor involves the nerve root as it exits the spinal canal = pain and paresis as clinical signs
Schwannoma morphology was characterized y the presence of Antoni type A and B patterns and immunoreacitivity for ___ protein and ____.
S100 and Vimentin
Canine granular cell tumors are positive for ____ and variable positive for cementing and S-100 protein.
neuron-specific enolase
In dogs, research and clinical observation strongly suggest that what may be the cause of hemagiomas in ventral glabrous skin of lightly pigmented, sparsely hairs skin?
chronic solar damage
Supportive IHC for hemangioma would including positive staining for what proteins?
Positive for vimentin, Factor VII related antigen (von willebrand factor), an type IV collagen and laminin = vascular proliferative markers
Supportive IHC for hemangiosarcoms would including positive staining for what proteins?
Positive for vimentin, factor VIII-related antigen, S100, type IV collagen, laminin
What are common neoplasms of the dog arising from vascular pericytes. The cause of these tumors is unknown, but chromosome abnormalities (trisomy 2,9,29) have been identified in dogs?
Hemangiopericytoma
Supportive IHC for hemangiopericytoma would including positive staining for what proteins?
positive for vimentin, but negative for cytokeratin, factor VIII related antigen, glial acidic fibrillary protein and S-100 protein.
Some may express actin, desmin, CD34 antigen
Supportive IHC for lymphangioma would including positive staining for what proteins?
Positive for vimentin, Factor VIII-related antigen and CD31
What breeds are predisposed to developing Lipomas in cats and dogs?
Siamese
Cocker Spaniels, dachshunds, Weimaraners, Doberman Pinchers, miniature schnauzers, Labs and small terriers
What breeds of dog are predisposed to developing infiltrative lipomas?
Doberman Pinchers and Labrador retrievers
What staining would help differentiate liposarcoma from other sarcomas?
Oil Red O
Leuiyomas and leiomyosarcomas are characterized histologically by interlacing bundles of smooth muscles fibers that tend to intersect at right angles, Cell nuclear are usually ___ shaped and ____ stains often helpful in distinguishing Mong tumors of muscles collagen nd neural origin.
Cigar
Masson Trichome
For diagnosis of Rhabdomyoma and rhabdomyosarcoma, _______ enhancers the appearance of cross-striation in tumor cells and bundles. Skeletal muscle tumors are positive for ____ and ____.
Phosphotungstic acid hematoxylin
desmin, vimentin
Three investigations evaluating the role of tumor suppressor gene or oncomutations have identified ____ protein in canine mat cell tumors by IHC staining. Of recent interest, is the potential role for constitutively activating mutations of _____ causing malignant mast cell transformation.
p53 protein
c-kit receptor tyrosine kinase
What breed is often younger than other breeds when they develop mast cell tumors.
Shar Peis
What breed and sex of cat is predisposed to developing MCT?
Male and Siamese
Occurring most commonly on head and neck
Canine mast cells are positive for the ____ which is confined to mast cells and basal cells.
serine protease tryptase
Describe the different grades of MCT
Grade 1 - well-differentiated and located in the dermis and inter follicular spaces
Grade 2 - intermit with rare mitotic figures and infiltration into the lower derma and subcutaneous tissue
Grade 3 - Anaplastic with 1 or more nucleoli, 3-6 mitotic figures/high power filed and in invasion into the subcutaneous and deeper tissues.
What is the most effective and best described adjuvant treatment currently utilized for managing incompletely resected cutaneous mast cell tumor.
External bean megavoltage radiation therapy
What is a radiation treatment modality whereby radioactive material sealed in needs, seeds, wire or catheters I placed directly into or near a tumor. _____ is a radioisotope capable or releasing both gamma and beta particles and can be used as radioactive source for brachytherapy.
Brachytherapy
Iridium-192
Local and faster than megavoltage radiation
What is the recommended course of treatment for feline MCT?
The vast majority are benign. Treatment usually includes cryotherapy and surgical resection.
NON-epitheliotropic lymphomas have been associated with what three other condition unrelated to skin?
- monoclonal or oligoclonal gammapathies
- serum viscosity
- hypercalcemia
Most non-epitheliotropic lymphomas are T cell, CD4 to CD8 phemnotypes. Rarely, are they B cell lymphomas. In cats, most cutaneous lymphomas (NE) are of T cell phenotype and ___ % are FeLV positive.
40%
How is mycosis fungicides characterized histologically?
Characterized by epitheliotropism, Pautrier micro abscesss and the presence of mycosis cells (large 20uM lymphocytes with hyper chromatic, indented or folded nuclei) and Sezary or Lutzner cells (smaller 8uM lymphocytes that have markedly hyperconvoluted nuclei with numerous finger like projections producing a classic cerebriform appearance.
In dogs, CTCL is generally a disease of ___ T cells, contrary to they human form, where mature ___ cells predominate.
CD8 Cytotoxic T cells
CD4
The majority of CTCL cases of mycosis fungoides express T-cell receptor ___ , the rest express ____.
TCR-yd
TCR-ab
List topical treatments for CTCL in dogs
- Mechlorethamine (nitrogen mustard) alkylating agent
- Carmustine (BCNU alkylating agent
- Bexarotene - Synthetic retinoid
- Aldara
- Phototherapy - UVA penetrates deeper than UVB
- CSA
- Lomustine
- L-Asparafinase - enzyme purified from e.coli that depletes the pool of L-Asparagine needed by the lymphocytes.
- Dacarbazine
- Doxorubicin
What are the two forms of pagetoid reticulosis?
localized lesions (Woringer-Kolopp) with a benign clinical course Generalized lesions (Ketron-Goodman form) with a progressive clinical course = more common
**CD3 and CD8 positive and exclusively yd T cells
What is a rare lymphohistiocytic proliferative disoder in dogs. The atypical lymphohistiocytic cells that characterize this disease are variable CD3 positive, suggesting the this is an atypical T cell lymphoma.
Lymphomatoid Granulomatosis
What tumor is of extramedullary plasma cell origin and are rarely associated with multiple myeloma. This is common in the dog and rare in cats.
Cutaneous Plasmacytoma
What breed is overrepresented to develop plasmacytomas?
Yorkies
IHC studies have shown that most plasmacytomas are positive for ___ and ____.
IgG heavy and light chains
Histiocytic Proliferative Disorders are functionally divided into what two categories? what are the 4 well recognized histolytic proliferative disorders?
dendritic cell tumors and macrophage tumors
Cutaneous histocytoma
Reactive histiocytosis
Histiosarcoma (localized and disseminated, aka malignant histiocytosis)
hemophagocytic syndrome (macrophage origin)
a majority of histiocytes differentiate from ____ stem cell precursors in the bone marrow into macrophages and one of three DC lineages: epithelial dendritic cells (Langerhan cells in the skin), interstitial DC and interdigitating DC (APC in the T-cell zone of lymph node).
CD34
___ and ___ induced macrophage development from CD34 stem cells.
GM-CSF and M-CSF
____, ____, ____ and ____ influence DC development from CD34 stem cells.
GM-CSF
TGF-b
IL-4
TNF-a
What are common benign neoplasms of the dog. Their cause is unknown. although they are more likely a unique proliferation or reactive hyperplasia rather than a true neoplasm? It is shown to be a proliferating Langerhan cell.
Cutaneous histiocytoma
What is the breed predilection in dogs for histiocytomas?
Boxers, Dachshunds, Grat Dane, Shetland Sheep dogs, Coker spaniels and Bull Terriers.
Some dogs present with multiple lesions at diagnosis and histiocytomas with regional lymph node involvement, most commonly seen in what breed?
Shar Pei
Describe the histopathology of a histocytoma
Characterized by sheets and cords of pleomorphic histiocytes infiltrating the dermis and subvutis. Despite its benign behavior, the mitotic index is often high. The presence of CD8 T cells is common in regressing lesions. Langerhan cells resemble the Pautrier micro abscesses of epitheliotropic lymphoma.
Histiocytomas are of epidermal langerhan cell piling via expression of what markers?
of CD1a, CD1b, CD1c, CD11c, E-Cadherin, MHCII
Negative for Thy-1 and CD4
What is the marker of activated DC?
CD4
The expression of what molecule is unique in histiocytomas?
E-cadherin
What is a benign proliferation of perivascualar dermal dendritic antigen presenting cells of dogs?
Cutaneous histiocytosis
What breed is predisposed to developing cutaneous histiocytosis?
Collies and Shetland Sheep dogs
In cutaneous histiocytosis, the overlaying epidermis usually lacks the prominent hyperplasia and rete ridge formation seen with histiocytoma. Histiocytic cells express what?
CD1a, CD1b, CD1c, CD11c, MHCII, Thy-1 and CD4
NOT E-cadherin (differentiates between CH)
What is a proliferative disorder of perivascular dermal dendritic antigen-presenting cells of dogs. The cause of the condition us known. It is thought to represent a “reactive histiocytosis” similar to its cutaneous counterpart.
Systemic histiocytosis
Systemic histiocytosis was first reported in what breed and its a polygenic mode of inheritance?
Bernese Mountain Dog
Predilection of Rottweilers, Labrador retrievers, Irish Wolfhounds, and Golden Retrievers.
With IHC, SH lesions express what?
CD1, CD11c, MHCII, Thy-1 and CD4
The majority of small lymphocytes present within the lesions of systemic histiocytosis have been demonstrated to be of T-cell origin ____ and ____.
Unlike cutaneous histiocytomas, the present of T cells is not associated with regression and likely secondary to cytokine induced migration.
CD3 and TCRab
50% were CD8.
Histiocytic sarcomas have been identified in a variety of breeds, mainly which ones?
Bernese Mountain dogs but also Rottweilers and Flat Coated Retrievers.
HIstiocytic Sarcomas present with a radpily growing localized soft tissue mass. Which area is most commonly affected?
The limbs are most commonly affected it the tumor site in close proximity to a joint owing to its origination from DC of the synovial lining.
In one sited, 18 of 35 tumors of synovial origin previously diagnosed as synovial cell sarcomas were reclassified as histiocytic sarcomas based on IHC expression of ____.
CD18
Localized and disseminated histolytic sarcoma is a neoplasm derived from dendritic cell origin, which can be confirmed by immunohistiochemistry, Tumor cells uniformly express what markers?
CD1b, CD1C, CD11a, CD18 and CD45 (indicative of leukocytes origin)
The low levels of E-cadherin rule out it being a histiocytoma
Low levels of Thy1/CD4 rule out it being cutaneous histiocytosis
Histiocytic sarcomas are positive for ___ and negative for ___ which distinguish it from being of epithelial origin.
lysozyme
cytokeratin
Malignant fibrous histiocytomas are uncommon in cats and rare in dogs. These neoplasms are believed to arise from undifferentiated _______ cells.
mesenchymal
Melanocytic neoplasm are relative common to dogs and arise from ___ and ___.
melanocytes and melanoblasts
In cats, melanomas have been produced with injections of ___, although viruses are not though to contribute the generation of spontaneous cutaneous melanoma felines.
FeSV
Which breeds of dogs are predisposed to developing sublingual melanomas?
Schnauzers, Scotties and Irish Wolfhounds
Melanomas are positive for ____ and variably positive for ____ and ______.
vimentin
S-100 protein and neutron-specific enolase
What is the therapy of choice in dogs? Survival time is determined by what 3 factors?
Radical surgical excision
Tumor size, mitotic index and Ki-67 (proliferating cell nuclear antigen)
What tumor is also known as Tickers sarcoma, and is a naturally occurring, horizontally transmitted tumor of dogs, occasionally observed in other canids?
TVT
In has been demonstrated in canine TVTs all have ________ upstream if the region coding for the oncogene c-myc. This specific molecule alteration in a retroviral-like fashion is inserted upstream of c-myc possibly leading to amplified gene transcription, is believed to be a key player in the tumorigenesis of TVT.
Long Interspersed Nuclear Elements (LINE)
Why are TVTs thought to be of histiocytic origin?
positive reactions to lysozyme, a1-trypsin, vimentin and macrophage specific immunostain (ACM1)
What is the best described and most effective approach for treatment of TVT?
Vincristine (tubulin binding agent)
Primary cutaneous neuroendocrine tumors are rare neoplasms and may be of what cell origin?
Merkel
IHC studies for Primary cutaneous neuroendocrine tumors reveal the these tumors stain positive for what?
cytokeratin and chromogranin A
What type of cyst are characterized by a cyst wall that undergoes trichilemmal differentiation ( no granular layer) and a cyst cavity containing a more homogenous amorphous keratin.
Isthmus Catagen Cyst
What type of cyst are characterized any a cyst wall of deeply basophilic basaloid cells which abruptly keratinizes to form eosinophilic amorphous keratin replete with ghost or shadow cells?
Matrical Cysts
Multiple epitrichial cysts may occur in the eyelids of what two breeds of cats?
Persian and Himalayan cats.
What is a circumscribed developmental defect of the skin, characterized by hyperplasia of one or more skin components?
Nevus (hamartoma)
Collagenous Nevi also know as _____, us a syndrome of multiple symmetrically distributed nevi on the limbs, head, ventral neck and trunk. This syndrome is common in GSD and is autosomal DOMINANT.
nodular dermatofibrosis
Collagenous Nevi in GSD is due to a mutation in what gene? What disease concurrently develop?
BHD
bilateral renal disease (cystadenomas or cystadenocarcinomas)
What type of Nevi are commonly found on the scrotum of Scotties, Airedales, Kerry Blue Terriers and Labrador retrievers?
Vascular nevi
Epidermal Nevi tend to follow _____ possibly resulting from genetic mosaicism in which two or more genetically different cell tunes are present within the same individual.
Blashko lines
What are firm, elected, circumscribed areas of reactive keratinocyte proliferation and excessive keratin production?
Keratoses
Which breeds have an increased risk of actinic keratoses?
Dalmations, Pittbulls, beagels and bassets
Actinic keratoses are premalignant lesions that are capable of becoming invasive _______.
SCC
Multiple cutaneous horns have been seen on the footpads of cats with what viral infection?
FeLV
Calcinosis cutis in dogs is thought to be ____ in nature, because blood calcium and phosphorous levels are normal.
Dystrophic mineralization
Calcinosis circumscripta is usually secondary to what cause? Most common breed affected?
occurs at sites of trauma (collars, polydioxanone sutures)
Young GSD
The amorphous material in calcinosis circumscripta is usually strongly positive for which stains?
Alcian Blue and PAS
**osseous metaplasia may occur in these lesions
In focal cutaneous mucinosis, the lesions will stain positive for what two stains?
Alcian Blue or colloidal iron
In canine cutaneous epitheliotropic lymphoma (mycosis fungoides), the neoplastic T-cells are predominantly?
CD3 and CD8 positive, and express T cell receptor γδ (gamma-delta)
