Neoplasia Flashcards
Which types of malignancies are the most common in canines?
Soft tissue sarcoma
Mast cell tumors
Lymphosarcoma
What type of tumors are the most common in canine?
Benign
Name in order of most common to least common the locations of neoplasia in canines.
Skin/soft tissue Alimentary Mammary Urogenital Lymphoid Endocrine Oropharyngeal
What is dysplasia?
Disorganization of the cells in a tissue/organ only seen unless the cells are viewed. It is generally considered pre-neoplastic, seen often with chronic irritation, can have cellular atypia, and is not a form of cellular adaptation.
What is neoplasia?
Tissue growth which exceeds and is uncoordinated with that of normal tissue. It persists in the same excessive manner even after the cessation of the stimuli that evoked the original change.
What is the basis of cancer?
A series of non-lethal genetic injuries
Describe the process of neoplastic transformation into malignancy.
It is a multi-step process involving:
- Initiation: non-lethal DNA injury
- Promotion: irratant that allow cell proliferation
- Progression: clonal expansion with changing cells/ tumor growth/metastasis
with the timing and order of these steps being essential.
What are the 4 major groups of genes altered in cell cycle regulation leading to oncogenesis?
- Apoptosis-regulatory genes
- Tumor suppressor genes (growth inhibition is stopped)
- Protooncogenes (growth promotion)
- DNA repair genes `
What is the difference between protooncogenes and oncogenes?
A protooncogene is a gene that is responsible for the normal promotion of proliferation and differentiation involving growth factor production, growth factor receptors, signal transducing messengers, and nuclear regulatory factors controlling transcription of DNA. An oncogene is a protooncogene that has an altered structure allowing for the abnormal promotion of self-sufficient growth.
