Bronchogenic carcinoma is a malignant neoplasm of the lung arising from the epithelium of the bronchus or bronchiole.


Accounts for 14% of all new cancers in males and 13% of all new cancers in females.

Seventy percent of all lung cancer deaths occur between the ages of 55 and 74. However, recent trends indicate that both the incidence and mortality of lung cancer is increasing in younger age groups.

It is approximately three times more common in men than females. However the incidence of lung cancer in females in increasing in epidemic proportions.

Lung cancer leads as cause of cancer deaths among women and men.

The countries with the highest incidence of lung cancer among males is the United Kingdom

In general, the incidence of lung cancer in industrialized western countries is increased compared to third world countries.

The highest incidence of lung cancer in the United states is in the northern urban areas and along the gulf and south Atlantic Coasts from Texas to Florida.


Today, the epidemiology of lung cancer is the epidemiology of smoking. Other factors are relatively of minor importance.
Cigarette smoke contains a number of proven carcinogens in both the particulate and gaseous phase including:
-Aromatic Hydrocarbons
Exposure to certain substances have a synergic effect in being causatively associated with the use of tobacco products in development of lung cancer.
-Chloromethyl Ethers
-Mustard Gas
-Radioactive Ore
Host Factors
As with most illnesses, the development of disease depends on a complex interaction between the environment and the host. Specifically with lung cancer, host factors play a relatively minor role.
-Risk of Second Primary
-Associated Malignancies
-Aryl Hydrocarbon Hydroxylase
-Scar Carcinoma

Bronchogenic carcinomas begin as a small focus of atypical epithelial cells within the bronchial mucosa. As the lesion progresses, the atypia becomes frankly malignant and the neoplasm grows in size. The neoplasm may grow into the bronchial lumen, along the mucosa or into the bronchial wall and adjacent lung parenchyma. Eventually the neoplasm spreads to regional lymph nodes and distant organs such as the liver, brain and bone. Most bronchogenic carcinomas form a mass in or near the hilus. Some neoplasms, especially the adenocarcinomas, form a mass in the periphery of the lung. Refer to Figure 15-42 in your textbook. The following classification scheme represents the major histologic types of
bronchogenic carcinoma. Refer to Table 15-10 in your textbook.


Natural History


It is likely that during the majority of a lung tumor's existence it will be undetectable by any currently available diagnostic technique.


Symptomatic Phase

About 95% of all lung cancer diagnoses are made during the phase when the disease has become symptomatic. Carcinoma discovered at this point in its natural history is almost always well advanced. With very few but significant exceptions, symptomatic lung cancer carries poor prognosis. This is because the vast majority of symptoms in this disease are caused by either locally unresectable or metastatic tumor.

Symptoms Grouping


During the past years, numerous investigators have been endeavoring to establish a standard terminology that would accurately describe the extent of a cancer. One such staging system for lung cancer has been formulated by the Task Force on Lung Cancer of the American Joint Committee for Cancer Staging and End-Results Reporting (AJCF). The AJC staging system employs the T-N-M nomenclature . In this system, the letter T represents the primary tumor N regional node involvement, M.

T. Numerical Suffix Assignment
The criteria are:
N Numerical Suffix Assignment
The first station lymph nodes are the intrapulmonary, peribronchial and hilar lymph nodes, which are contained within the visceral reflections. Second station lymph nodes are those in the mediastinum and may be paraesophageal, subcarinal, paratracheal, aortic or retrotracheal. Involvement of scalene, contra-lateral or extra-thoracic nodes is considered distant metastasis.
M Suffix Assignment
The metastatic status is signified by the letter "M" with subscripts O or 1 to indicate absence or presence of metastatic disease. "M1" signifies presence of metastasis in one or more distant organs. The common metastatic sites are Brain, Bone, Liver, Adrenal glands and subcutaneous tissue.
Group Staging
T, N and M combinations are used to group stage lung cancer. The staging is important in planning therapy and for estimating prognosis.

Principles of Therapy

Therapeutic options consist of:

Non-small cell cancer in stages 1, 2, 3a in acceptable general condition as a surgical candidate are best suited for this modality. In general, small cell cancer is not a surgical disease.
Radiation Therapy
If the general condition precludes the patient from being a surgical candidate, Radiation therapy is chosen. Palliative Radiation therapy has an important role for relief of symptoms in inoperable cases.
Chemotherapy is the treatment of choice for small cell cancer. Its role in NSCC is under investigation.
Supportive Care

One needs to consider the following in to determine the best option.


Lung cancer is a preventable disease. If cigarette consumption is stopped, we can probably prevent 99% of lung cancers. As a physician, it is your obligation to set an example by not smoking and to advise patients not to smoke. You can offer options to aid patients in quitting their habit.

Take an active role in bringing legislation to curb the use of cigarettes in public places. Additionally, advertisements should be discontinued which encourage children to start the habit. We probably should not attempt to ban cigarettes completely. It is unlikely to succeed, as we have learned from our past experience in trying to ban alcohol.