Abnormal new tissue growth characterized by the progressive uncontrolled multiplication of cells.
Bronchogenic Carcinoma/Lung Cancer
The most common malignant neoplasm in the lung originates from the bronchial mucosa.
Orginating in the lung
Slow growing, not life threatening, encapsulated, well-defined, localized
Disorganized growth, invasice & metastatic.
Moves to lung from another source.
Primary lung cancer is the most common malignancy in the USA
One of the leading causes of death
25% of Americans dying from cancet die from bronchogenic cardinoma
Lung cancer has become the leading causes of death from cancer in woemn primarily because of the increased rate of cigarette smoking among women
Leads to the majority of lung cancers.
Smokers have ten times the chance of dying from lung cancers as nonsmokers
Exposed to cigarette smoke also have an increased risk of lung cancer
On the job exposure
Carcinogens such as asbestos, uranium, insulations, brake materials, & petroleum products
Asbestos exposure have also been linked to lung cancers
a radioactive inert gas that is produced by rocks, soil, and groundwater. Radon consideredd the second most common cause of lung cancer in the United States
Genetic & Familial Factors that predispose individuals to bronchogenic carinoma
Lung cancer is seen predominantly in persons between the ages of 45 & 75 years with a peak at age 70, it is rare occurrence in persons less tha the age of 35
Pathologic Structural Changes
Inflammation, swelling, & desctruction of the airways & alveoli. Excessive mucus production.
Airway obstruction either mucus or tumor obstruction
Atelectasis, pneumonia, lung abscess due to bronchial obstruction
Lymph nodes, liver, bone, braub, & adrenal glands are among common sites for distant metastasis.
Lung Cancer Genes Identified
3 genes are associated with 20% of lung cancers, and these same genes are linked to fetal lung development, researchers report
These 3 genes work together to enable cancer cells appear to be unique to lung cancer
Discovered a frequent genetic mutation in lung cancer. This mutation is found in 20% of non-small cell lung cancer which makes up 80% of all lung cancer.
It may be possible to block these gene mutations and prevent tumor growth, Understanding how these genese work is importatnt for emdical applications.
4 types of bronchogenic Tumors
Non-Small- cell cancer:
- 1. Squamous Cell Carcinoma
- 2. Adenocarcinoma
- 3. Large Cell Carinoma
- Small-cell lung cancer:
- 1.Small Cell Carinoma (Oat Cell)
Squamous Cell Carcinoma
Most common in men (30%-50%)
Doubles every 100 days
Late local metastatic tendency
Can obstuct airways
Commonly located in large bronchi near the hilar region
Small Cell Carcinoma
Commonly called "Oat Cell"
Commonly found near hilar region
Doubles every 30 days- rapid
Metastasizes early- poor prognosis
20-25% of bronchogenic cancer
Strong correlation with cigarette smoking
Arises from the mucus glands of the tracheobronchial tree
Doubles/ 180 days- moderate
Found in peripheral portion of lung parenchyma
Cavity formation and pleural effusions are common
Large Cell Carcinoma
Growth rate is rapid
Doubles every 100 days
Seen in about 10-15% of bronchogenic carcinoma cases
Secondary complications include chest wall pain, pleural effusion, pneumonia, hemoptysis and cavity formation