Cutaneous Neoplasia

Question 1

What is a benign tumor?

Answer 1

(A tumor that lacks the ability to metastasize, does not mean it cannot be local aggressive)

Question 2

What is a malignant tumor?

Answer 2

(A tumor that has the ability to metastasize)

Question 3

Sarcoids are…

A - Non-metastatic soft tissue carcinomas
B - Non-metastatic soft tissue sarcomas
C - Non-metastatic soft tissue round cell neoplasms

Answer 3

(B, sarcoids are mesenchymal cell tumors = sarcoma)

Question 4

What are the different morphological types of sarcoids?

Answer 4

(Nodular, verrucous, flat/occult, and fibroblastic)

Question 5

Sarcoid formation is associated with the inactivation of the p53 gene (gene that stimulates apoptosis in normal cells) by what virus, which also enhances immunotolerance and production of regulatory T cells?

Answer 5

(Bovine papilloma virus)

Question 6

Squamous cell carcinoma is…

A - A malignant mesenchymal neoplasia
B - A malignant round cell neoplasia
C - A malignant epithelial neoplasia

Answer 6

(C)

Question 7

Describe squamous cell carcinoma.

Answer 7

(Fleshy, cobblestoned masses that can be ulcerative or proliferative and are often accompanied by a secondary bacterial infection)

Question 8

What are risk factors for the development of squamous cell carcinoma?

Answer 8

(Exposure to UV radiation particularly of non-pigmented skin, increasing age, exposure to the equine papillomavirus)

Question 9

What cells are malignantly transformed in cases of melanoma?

Answer 9

(Melanocytes)

Question 10

Why are grey horses predisposed to forming melanomas?

Answer 10

(Bc the genes associated with melanoma are found in the same areas of a specific chromosome as the genes for the grey phenotype)

Question 11

What cells are malignantly transformed in cases of lymphoma?

Answer 11

(Lymphocytes)

Question 12

What are some of the paraneoplastic syndromes that can occur in a horse with cutaneous lymphoma as it progresses?

Answer 12

(Lymphoma typically spreads to the local lymph nodes, liver, and spleen first then the blood (leukemia), can cause IMHA, IMTP, and agammaglobulinemia or hyperglobulinemia)

Question 13

What is the gold standard diagnostics test for cutaneous neoplasms?

Answer 13

(Biopsy)

Question 14

When are incisional biopsies a better choice than excisional?

Answer 14

(When the neoplasm is large and in an unfavorable location; if it is small (1-2 cm) and in a favorable location then excisional is the way to go)

Question 15

Which of the following correctly describe a biopsy? Multiple answers are true.

A - Biopsies transform benign lesions into malignant ones
B - Biopsies accelerate cell proliferation and therefore must be followed by treatment
C - Biopsies complicate future treatment
D - Biopsies increase the chance of metastasis
E - Biopsies allow for appropriate identification and treatment

Answer 15

(B and E are correct)

Question 16

What is the most efficient way to eliminate the greatest number of cancer cells?

Answer 16

(Surgery, if possible should be the first objective in cancer therapy, allows for less radiation and/or chemotherapy to be used in the future)

Question 17

You need at least how many centimeters of normal tissue on histopath at all margins of a neoplasm to call the area “clean” of cancer?

Answer 17

(0.5 cm)

Question 18

Which of the following chemotherapeutics is a pyrimidine antagonist that inhibits DNA synthesis?

A - 5-FU
B - Imiquimod
C - Mitomycin C ophthalmic ointment

Answer 18

(A)

Question 19

5-FU is proven effective for the treatment of what cutaneous neoplasm in horses?

Answer 19

(Squamous cell carcinoma, less evidence of effectiveness against sarcoids)

Question 20

Imiquimod is an immune response modifier that causes an intense inflammatory response to the area of application, it is mostly used for what cutaneous neoplasm?

Answer 20

(Sarcoids)

Question 21

Mitomycin C ophthalmic ointment, which inhibits RNA and alkylates DNA resulting in chromosomal breakage, is an excellent treatment option for what cutaneous neoplasm?

Answer 21

(Squamous cell carcinoma of the eye)

Question 22

Intratumoral cisplatin causes what event to occur in tumor cells by cross-linking with purine bases and interfering with DNA repair?

Answer 22

(Apoptosis)

Question 23

Electrochemotherapy is the injection of a cytotoxic chemotherapy agent followed by an electrical current, what is the purpose of the electrical current?

Answer 23

(The electrical current increases cell permeability which increases the intracellular uptake of the cytotoxic agent)

Question 24

What is the main goal of immunotherapy used for treatment of cancer?

Answer 24

(Immunotherapy attempts to stimulate the host’s immune system to destroy cancer cells)

Question 25

The oncept vaccination is used for treatment of what cutaneous neoplasia?

Answer 25

(Melanoma → oncept stimulates the development of antibodies to tyrosinase which is overexpressed in melanoma tissue, need peer-reviewed evidence of efficacy still)

Question 26

When is systemic chemotherapy indicated?

Answer 26

(Systemic cancer, metastatic cancer, non-surgical solid tumors, or solid tumors where clean surgical margins were not achieved)

Question 27

(T/F) Lymphoma originates in skin-associated lymphoid tissue as single or multiple haired masses.

Answer 27

(T)