{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Release substances that affect neurologic function

Info iconThis preview shows pages 2–4. Sign up to view the full content.

View Full Document Right Arrow Icon
release substances that affect neurologic function and may have hormonal effects Diagnostic Test Routine screening and self-examinations are good for early detections of cancer and treatment monitoring Blood tests: Measure blood cell levels during treatments or may detect tumor markers (ex: PSA test) Radiographic, ultrasound, MRI, and CT Scans: methods of visualizing changes in the tissues and organs Cytologic tests require biopsy or cell sample: histologic and cytologic exam (differentiation and tumor type) or column diagnosis Spread of malignant tumors Invasion: local spread, in which the tumor cells grow into adjacent tissue and destroy normal cells (ex: uterine carcinoma invading vagina) Metastasis: spreading to distant via blood or lymph or other body fluids (ex: carcinoma of the colon spreads to the liver) Seeding: spread of cancer in body fluids or along membranes usually in body cavities Staging of cancer: classification process applied to a specific malignant tumor at the time of diagnosis. Essential to standardize comparative studies of treatments and outcomes to estimate a prognosis (basis for treatment) Most common system used is the TMN system : -Size of primary tumor (T) -Involvement of regional lymph nodes (N) -Spread (metastasis) of tumor (M) Carcinogenesis: process by which normal cells are transformed into cancer cells. The process varies greatly with respect to time. Cancer is thought to be multi-factorial disease due to: -Environment effects -Changes in gene expression (heredity) -Infections in some cases such as cervical and hepatic cancers Some cancers have well-established risk factors Stages of carcinogenesis 1. Initiating factors : procarcinogens cause first irreversible change in cellular DNA however this initial change does not create active neoplasm 2. Exposure to promoters : (includes hormones and environmental chemicals) this causes
Background image of page 2

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
further changes in DNA, resulting in less differentiation and increased rate of mitosis. Dysplasia or anaplasia may be evident. This process leads to tumor development. 3. Continued exposure and changes in DNA result in malignant tumor that is capable of growth and invasion of local tissue 4. Changes in regulation of growth result in cells that are capable of detaching from tumor and spreading to distant sites (metastasis) Risk factors Genetic factors: oncogenes that regulate growth Viruses- oncoviruses alter host cell DNA Radiation: ultraviolet rays, x-rays, gamma rays, and radioactive isotopes. Risk is increased with high cumulative dosage Chemicals: organic solvents, asbestos, heavy metals, formaldehyde, and chemotherapy agents Biological factors: irritation and inflammation, age, diet, hormones, limiting UV exposure from sun or tanning booths, regular medical and dental exams, and self- examination Diet: increased fiber content and reduced fats, 5-10 servings of fresh fruits and vegetables (contain antioxidants, which reduce changes to DNA) Immunization: for cervical cancer and hepatitis is recommended to reduce cancer risks from infection Treatment Depending on specific cancer
Background image of page 3
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page2 / 22

release substances that affect neurologic function and may...

This preview shows document pages 2 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon bookmark
Ask a homework question - tutors are online