Unit 5: Neoplasia General + Canine (Cram)

Abnormal developmet or growth of tissue, organs, or cells

Dysplasia

Increase in the number of cells

Hyperplasia

Loss of differentiation of cells, can be a feature of neoplasia

Anaplasia

Conversion of a mature tissue type into a different type

Metaplasia

Shrinkage in the size of the cells in response to stimulus

Atrophy

Increase in the size of cells in response to stimulus

Hypertrophy

Uncontrolled proliferation of abnormal cells to form neoplasms (cancer or tumors)

Neoplasia

Group of cells that have lost normal growth control mechanisms. They can be malignant or benign

Neoplasm

Term used to mean the spread from one part of the body to another

Metastasize

Term exclusively used to refer to a malignant neoplasm

Cancer

Term that means swelling, but often misused to mean neoplasm

Tumor

The study of cancer

Oncology

Giving rise to cancer

Oncogenic

Any substance with the potential to cause neoplasia

Carcinogen

Cells of mesodermal origin that are capable of developing into connective tissues, blood, and lymphatic and blood vessels

Mesenchymal

How is the structure (resemblance to normal cells) of benign and malignant neoplasias described respectively?

Benign – Resemblance to normal cells

Malignant – Abnormal

How is the effect on the host of benign and malignant neoplasias described respectively?

Benign – Slight harm

Malignant – Significant harm

What is the prefix used to denote a tumor that originates from fibrinous tissue?

Fibro–

What is the prefix used to denote a tumor that originates from bone?

Osteo–

What is the prefix used to denote a tumor that originates from cartilage?

Chondro–

What is the prefix used to denote that a tumor has a glandular origin?

Adeno–

What is the suffix that denotes a benign tumor of any source?

–oma

What is the suffix that denotes a malignant tumor of supporting tissue origin?

–sarcoma

What is the suffix that denotes a malignant tumor of epithelial tissues?

–carcinoma

What is the suffix that denotes a tumor of embryonic origin?

–blastoma

Are blastomas usually malignant or benign?

Malignant

Can tumor be of mixed origin?

Yes

Growth pattern where benign tumors grow as well defined and discrete masses that may be freely movable and often have a capsule surrounding them

Direct expansion

Growth pattern where cells grow directly into the tissue surrounding the tumor

Invasion/ infiltration

Growth pattern where cells spread to another area not directly connected with the original site

Metastasis

What are the three steps of metastasis?

Remember: (This unit is) Really Too Long

1. Release from a primary site

2. Transport to new site

3. Lodging and survival at the secondary site

What is a common place for metastatic neoplasias to lodge?

Lungs

What are the three routes metastatic neoplasias can take in order to spread?

1. Bloodstream

2. Lymphatics

3. Transplantation (rubs off onto nearby tissue)

What are the three ways neoplasias are collected for microscopic examination?

1. Fine needle aspirate/punch biopsy

2. Exfoliate cytology

3. Impression smear

Tobacco smoke, papilloma virus, estrogens, testosterones and helicobacter are all examples of what?

Carcinogens

What are the two risk (predisposing) factors associated with neoplasia?

1. Age

2. Genetics

Which is the animal species most commonly affected by cancer?

Dogs

What is the most common tumor of dogs?

Canine mammory tumors

The incidence of mammary tumors is directly related to the number of _____ the bitch experiences

heat cycles

Mammary tumors may contain hormone receptors that stimulate growth in the presence of female hormones. When should you spay your dog to best avoid mammary tumors?

Before the first heat

What percent of mammary tumors are benign and malignant respectively?

Benign – 50%

Malignant – 50%

What are the three most common types of testicular cancer in dogs?

1. Sertoli cell tumors

2. Interstitial cell tumors (aka Leydig cell tumors)

3. Seminomas

Which condition predisposes a dog to Sertoli cell tumors?

Cryptorchidism (undescended testes)

What percent of Sertoli cell tumors will produce estrogen, resulting in feminization, hair loss, anemia, and attraction of male dogs?

30% produce estrogen

Which testicular tumor shows very few symptoms? Occassionally it is associated with increased production of androgens which can cause aggression or increased libido

Interstital cells tumor

Which testicular tumor arises from the cells of the testicle that normally produces sperm. It does not secrete hormones

Seminomas

What are the four well recognized anatomic forms of canine lymphoma?

1. Multicentric

2. Alimentary

3. Mediastinal

4. Extra nodal

What are some breeds of dogs that are commonly affected by canine lymphosarcomas?

Golden retrievers, Rottweilers, Pit Bulls, Poodles, German Shepherds, Boxers, etc.

Which canine lymphosarcoma is the most common?

Multicentric (80%)

Which canine lymphosarcoma is not common?

Alimentary (10%)

What is the canine neoplasia that is most common in Saint Bernards, Rottweilers, Great Danes, Golden Retrievers, Irish Setters, Doberman Pinschers, and Labrador Retrievers (giant and large breeds)?

Canine osteosarcoma (OSA)

What demographic and which breed is most affected by canine hemangiosarcoma (HSA)?

Older large breed dogs, German Shepherd most common

What is the most common site of canine hemangiosarcoma tumor development?

Spleen (but it can arise in any tissue with blood vessels: heart, subQ, and liver also common)