Unformatted text preview: Cancer Cancer
NURS 216, SPRING 2010 Sabra H. Smith, MS, RN Cancer is a problem of incorrect cell differentiation, replication or apoptosis apoptosis The Cell Cycle The A Replication Problem Replication
Normal cells “rest” in stage Go Carcinogenesis (development of cancer) begins with a DNA mutation which changes normal cell replication The normal controls to prevent overreplication are lost Types of mutations: point mutation, gene amplification, chromosome rearrangement, viral genome insertion Differentiation Differentiation Stem cells: pluripotent and adult Progenitor cells are further specialized Increased specialization means mitosis ability is decreased Types of Abnormal Differentiation Types Metaplasia – when a type of cell changes into another type which is normal but in the wrong place Dysplasia – control of differentiation is lost and the cells become disorganized: size and shape are random. Usually progresses to cancer Dysplasia Dysplasia The surface cells are lined up in an even row. The nuclei of the cells are normal appearing and neatly lined up along the basement membrane. The surface cells are NOT in neat, even rows. The nuclei are large and the glands are distorted. Neoplasia Neoplasia Neoplasms are new growths of tissue in an area of the body, AKA tumors Arise from previously normal cells, but the new cells grow uncontrolled Serve no beneficial purpose, usually harmful Can be benign or malignant Benign Neoplasms Benign Noncancerous – the new growth is contained locally Cells are cohesive, contained and differentiated, as the tumor grows it pushes away other tissue Do NOT spread to distant sites Growth rate of benign tumors varies Are only fatal if interfere with vital functions Malignant Neoplasms Malignant Grow progressively and rapidly, undifferentiated Cells are not held together and are uncontained > irregular border and spreads easily to other tissues Invade the surrounding tissue Original tumor is the “primary” site This is true CANCER Terminology Terminology Generally, tumors are named using the originating tissue/organ + oma Malignant tumors usually “sarcoma” Contact inhibition Metastasis Metastasis The process of malignant tumor cells spreading from the primary site to other areas of the body Can occur in several ways: through blood vessels, lymphatic system, may cross the lining of an organ or body cavity Effects of Neoplasms Effects Benign tumors usually have local effects: may exert pressure, constrict an opening, or replace normal tissue Malignant tumors do all of the above, but quicker Structure of Neoplasms Structure Stroma – framework of connective tissue and blood vessels Differentiation – how similar are the tumor cells to the original tissue? Especially in malignant tumors, the individual cells look different larger and irregular nuclei, irregular cell shape Classification Classification Grading: IIV, indicates degree of disorganization of cells Staging: clinical spread of the tumor Chart 52 TNM staging system: Tumor 04 Nodal involvement 03 Metastasis x1 Clinical Aspects Clinical Most common sites of cancer: prostate/breast (30%), lung (14%), colorectal (10%) Diagnosis made by imaging studies, cytologic smears, tissue biopsies Treatment methods: surgical removal, radiation, chemotherapy, immunotherapy Treatment Treatment Can be curative, control, or palliative Surgery Radiation Chemotherapy cell cycle specific or nonspecific usuallyin combination side effects: ...
View Full Document
- Spring '10
- cells, Cancer Cancer, Malignant tumor cells