Cancer Epidemiology and Risk Factors Flashcards
Predisposition to neoplasia
Heredity
Age (older, young for certain cancers)
Gender
Pigmentation (lack of)
Hormones
Chronic irritation (damaging cells)
Parasites (spirocercalupi)
Old age
↑ with age
High incidence in companion animals
↑ incidence in the third trimester
Young age
Young dogs (< 6 m) have high incidence of hematopoietic, skin and brain tumors
Mast cell tumor (boxers)
Lymphoid neoplasia (cats and cattle)
Mesotheliomas (neonatal calves)
Cutaneous neoplasms (young horses)
Boxers
High incidence of neoplasia (mast cell tumors)
german shepherds
Hemangiosarcoma (spleen and r. atrium)
Large breed dogs
Osteosarcomas
BRachycephalic breeds
CNS and aortic body tumors
Sinclair and Hormel mini pigs and Duroc jersey swine
Melanomas
Bernese mountain dogs
Malignant histiocytosis
Cattle, horses
Granulosa thecal cell tumor (ovary)
Cats, cattle
Lymphosarcoma, leukemia (FeLV, BLV)
Horses
Sarcoid, pendunculated lipoma
Dogs
mammary gland neoplasia
Chickens
Marek’s disease- herpesvirus
Pigmentation
White coated animals → squamous cell carcinoma
Grey horses Melanomas
Parasite increasing sarcomas:
Spirocera lupi (+ chronic infection)
Hormones
Excessive hormone stimulation
Associated with genetic predisposition to tumor formation (mammary and circumanal/ perianal gland tumors)
Canine mammary neoplasia incidence
OVH before first estrus: 1/100 dogs
OVH after first estrus: 1/12 dogs (8%)
OVH after second estrus: 1/4 dogs (25%)
Clinical effects of neoplasia
Atropy of surrounding cells, obstruction of lumen or organs
Tissue, blood or lymph supply, n. supply destruction
Bacterial invasion of neoplasm, anemia, hormone production, death, spontaneous regression or recovery
Clinical features of neoplasms
Clinical abnormality with organ affected
Cancer cachexia
Outward lesions
Paraneoplastic syndromes
Paraneoplastic syndromes
Systemic complication or illness of neoplasia remote from the primary tumor
Could cause illness/ death
Paraneoplastic syndrome treatment
Concentration of product decreases after removal or treatment of neoplasm
Product concentrations maintained after removing normal gland that controls the product secretion
Categories of paraneoplastic syndromes
Endocrinopathies (hypercalcemia of malignancy and cushing’s)
Neuromuscular disorders
Dermatologic Disorders
Osseous, Articular and soft tissue changes (hypertrophic osteoarthropathy)
Hematologic and vascular changes
Cushing’s
Small cell cancer of the lung
Pancreatic carcinoma and neural tumors
ACTH
Hypercalcemia of malignancy
Squamous cell carcinoma of lung
Renal or breast carcinoma
Adult lymphoma/ leukemia
PTH-like, TGFa, VD
Polycythemia
Renal carcinoma
Hepatocellular carcinoma
Erythropoietin
Hypertrophic osteoarthropathy
Occurs with pulmonary tumors - lung adenocarcinoma
Proliferation of osseous tissue in the bones of distal limbs
Myasthenia gravis
Thymoma paraneoplastic syndrome
Thymic neoplastic cells produce anti-Ach receptor Abs
Pathological dx of neoplasms
Biopsy (H&E) with special stains and immunohistochemistry
Cytology
Glor cytometry
Necropsy
__________ is more valuable in a clinical setting
Staging
Grading
Estimates aggressiveness based on cytologic differentiation of tumor cells and # of mitoses
Grades 1-4, varied with tumor type
Reflects ↑anaplasia
Staging
Size of tumor, extent of spread to LNs, presence or absence of metastases
The TNM System- UnionInternational Contre Cancer (UICC)
T: tumor size, T1-T4
N: node involvement N0 -…
M: absence of presence of metastases M0-M1
based on tumor type
Conventional treatment
Surgery
Chemotherapy
Radium
Immunotherapy
Surgery.
Wide margins (3 cm all sides)
Ink surgical margins, tag with suture
Chemotherapy
Alkylating Agents
Antibiotic antineoplastics (DNA damage)
Mitiotic inhibitors (binds to tubulin)
Hormones (prednisone- lympholytic)
Alkylating agents
Alkylates DNA → miscoding and cross linking DNA strands
Cell cycle nonspecific, active in resting
Radiation
Radiation beams (external)
Radioisotropes (internal)- I-131- radioactive iodine
Immunomodulatory therapy
Modulate immune system
1st USDA approved canine vx for melanoma (Oncept)
Monoclonal Abs for B cells (blontress) and T cells (tactress)
Unconventional treatments
Holistic therapy
Special diets
Acupuncture