Transcript File

Oncology
Chapter 19
Learning Outcomes
• Define cancer.
• Describe cell differentiation.
• Identify the staging system that evaluates the
spread of a tumor.
• Contrast the characteristics of benign and
malignant tumors.
• List the seven warning signals of cancer.
Overview of Cancer
• Cancer refers to any malignant tumor.
• Incidence of cancer is five times higher than 100
years ago.
• Strikes 1 of every 3 Americans.
• Has become one of the more treatable of the
major diseases in the U.S.
• Highly advanced surgical techniques
• Chemotherapy and radiation therapy
• Immunotherapy and photodynamic therapy
Top 10 Cancers by Death RATE
in US
• https://nccd.cdc.gov/uscs/toptencancers.aspx
• https://nccd.cdc.gov/uscs/toptencancers.aspx
http://www.cancer.gov/about-cancer/what-is-cancer
7
Types of Cancer
• Four broad types of cancer:
• Carcinomas: arise from epithelial tissue (skin, lining of the
intestines and body cavities, surface of body organs, outer
portion of glands)
• Sarcomas : arise from connective tissue (bone, tendon,
cartilage, muscle, fat tissues)
• Leukemias: cancers of the blood which originate in the
bone marrow or the lymphatic system
• Lymphomas: cancers that originate in lymph nodes and
glands
Classification of Cancer
• Helps determine appropriate treatment and
prognosis.
• Tumors are classified according to:
• Anatomic site of origin
• Grading- determined by pathologists to
describe cell division
• Staging – how the disease is spreading
through the body
• http://www.cancer.gov/types
Classification of Cancer
• Anatomic Site
• Indicates where the cancer originated in the
body.
• Carcinomas make up the great majority of all
cancers.
• Malignant tumors of epithelial tissues
• The opposite of malignant is benign
(Etymology: L, benignus, kind)
Table 19.1 Characteristics of
Benign and Malignant Tumors
Classification of Cancer
• Anatomic Site
• Carcinomas make up the great majority of all cancers.
• Examples
• Squamous carcinoma (squamous epithelium)
• Basal cell carcinoma (skin cancer)
• Bronchogenic carcinoma (bronchus of respiratory tract)
• Sarcomas – sarc/o and omas
• Leukemia
• Lymphomas
• Myelomas (look up in book now, noticed the combining
form myel/o
Figure 19.2
Squamous cell carcinoma.
Cell Differentiation and
Grading
• Normal cells
• Reproduce themselves through mitosis (mit/thread,
osis/condition), an orderly process that assures growth,
tissue repair, and cell reproduction.
• Have a distinct appearance and a specialized function.
• In normal cell development, immature cells undergo
normal changes as they mature and assume their
specialized functions.
• This process is called differentiation.
How cancer cells behave
differently
• http://ed.ted.com/lessons/how-do-cancer-cellsbehave-differently-from-healthy-ones-georgezaidan#review
Cell Differentiation and
Grading
• In cancer, a cell or group of cells undergoes
changes and no longer carries on normal cell
functions.
• This failure of immature cells to develop
specialized functions is called
dedifferentiation.
• It is believed that this process involves a
disturbance in the DNA of the affected cells.
Cell Differentiation and
Grading
• Malignant cells
• Usually multiply rapidly, forming a
mass of abnormal cells that
enlarges, ulcerates, and sheds
malignant cells that invade
surrounding tissues.
• These malignant cells take the place
of normal cells.
Cell Differentiation and Grading
• Malignant cells
• Under the microscope, a malignant cell reveals:
• a loss of differentiation
• Anaplasia (ana (up and apart)/plasia
(formation)
• nuclei of various sizes that are hyperchromatic
(hyper/chromatic (color))
• cells in the process of rapid and disorderly
division.
Cell Differentiation and Grading
• Based on microscopic analysis, malignant tumors are
classified as:
• Grade 1
• The most differentiated and the least malignant
tumors.
• Only a few cells are undergoing mitosis; however,
some abnormality does exist.
• Grade 2
• Moderately undifferentiated.
• More cells are undergoing mitosis, and the pattern is
fairly irregular.
Cell Differentiation and Grading
• Based on microscopic analysis, malignant tumors are
classified as:
• Grade 3
• Many undifferentiated cells.
• Tissue origin can be difficult to recognize.
• Many cells are undergoing mitosis.
• Grade 4
• The least differentiated and high degree of
malignancy.
Cell Differentiation and Grading
• Tumor grading is used to:
• Report the prognosis of the disease.
• Determine whether the tumor is
likely to respond to radiation therapy
or chemotherapy.
• Determine the prognosis for surgery.
Invasive Process
• Invasive Growth
• Active migration
• The malignant cells:
• Break away from the neoplasm.
• Invade surrounding tissue.
• Divide.
• Form secondary neoplasms.
• Then reunite with the primary tumor
as growth continues.
Invasive Process
• Metastasis
• Cancer cells spread from a primary site to
distant secondary sites by:
• invading the bloodstream or lymph
system.
• becoming lodged at a secondary site
where they form a neoplasm.
• Development of a secondary neoplasm
depends on the viability and the receptivity
of the organ.
Figure 19.3
How cancer cells invade normal tissue.
Staging
• The staging system that indicates the spread
of a tumor uses the letters:
• T (tumor)
• N (node)
• M (metastasis)
• Uses numerical subscripts to indicate degree
of tumor involvement.
• Example: T2N1M0
Staging
• Numerical system to classify the staging of cancer:
• Stage 0: Cancer in situ.
• Stage I: Cancer limited to the tissue of origin.
• Stage II: Limited local spread of cancerous cells,
sometimes to lymph nodes.
• Stage III: Extensive local and regional spread of
cancer, usually to draining lymph nodes.
• Stage IV: Distant metastasis.
Characteristics of Neoplasms
• The American Cancer Society lists seven warning signals of
cancer using the first letters of the word CAUTION:
• Change in bowel or bladder habits.
• A sore that does not heal.
• Unusual bleeding or discharge.
• Thickening or lump in breast or elsewhere.
• Indigestion or difficulty in swallowing.
• Obvious change in a wart or mole.
• Nagging cough or hoarseness
Diagnosis
• A variety of diagnostic tools and
procedures is used to detect the
possible presence of cancer:
• Examination
• Visualization by endoscopy
• Laboratory analysis
• Biopsy (Bx)
• Diagnostic radiology
Diagnosis
• Examination
• American Cancer Society
recommends certain cancer
detection tests be included in an
annual physical examination.
• Visualization by endoscopy
• Provides the physician a direct view
of certain portions of the body.
Diagnosis
• Visualization by endoscopy-679
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Sigmoidoscopy
Laryngoscopy
Bronchoscopy
Gastroscopy
Cystoscopy
Colposcopy
Proctoscopy
Colonoscopy
Laparoscopy
Diagnosis
• Laboratory analysis
• Plays a key role in detecting specific types of
cancer.
• Pap smear/test
• Cytologic screening test used to detect the
presence of abnormal or cancerous cells
from the cervix and vagina.
• Fecal occult blood test
• Test to detect occult (hidden) blood.
• If blood is present, check for possible
cancer of the colon.
Diagnosis
• Laboratory analysis (listed on page 679)
• Sputum cytology test
• Microscopic examination of sputum to detect abnormal
or cancerous cells of the bronchi and lungs.
• Blood serum test
• Analysis of blood serum to obtain useful information
about certain proteins synthesized by cancer.
• Two such tests are the AFP and hCG.
Diagnosis
• Biopsy
• The surgical removal of a small piece of
tissue for microscopic examination.
• Method to positively diagnose cancer.
• Excisional
• Surgical removal of a piece of tissue
from the suspected body site.
Diagnosis
• Diagnostic radiology
• Encompassing a wide range of tests
and procedures that can reveal
tumors that were not detected by
other diagnostic procedures.
Treatment
• Methods of cancer treatment
• Surgery
• Chemotherapy
• Radiation therapy
• Immunotherapy
• Photodynamic therapy
• http://www.cancer.gov/aboutcancer/treatment/types
Look at pages 704-705
• Prefixes
• Combining Forms
• Suffixes
• Medical Terms