Lung cancer (teratment)

- The treatment of lung cancer is dependent on the type and stage of cancer.
- The treatment explained here is only a summary:

1) Non-small cell lung cancer

* Stages IA, IB, IIA, IIB & some IIIA :

- basically the tumour is resected with / without removal of the lymph nodes in the mediastinum.
- post-operative radiotherapy is only advocated for selective patients.(with N2 disease if no neoadjuvant chemotherapy)

* Stage IIIA & IIIB

- The treatment for this stage of lung cancer is a little more complicated in that it depends also on the nature of the tumour i.e. bulky, with/without chest wall invasion,etc.
- It is suffice to say that resection of tumour is followed up with chemotherapy or radiotherapy.

* Stage IV & more advanced IIIB

- For this stage, radiotherapy to site of the involved area for relieve of symptoms.
- Chemotherapy for ambulatory patients.
- Resection of primary tumour and tumour spread (metastases) will be considered.

2) Small cell lung cancer

- limited stage (good performance status) : chemotherapy + chest radiotherapy
- Extensive stage (good performance status) : combination chemotherapy
- complete tumour responders (all stages) : consider prophylactic cranial radiotherapy
- Poor-performanc-status patients (all stages) :modified-dose combination, palliative care.

3) All patients

- radiotherapy for brain metastases, spinal cord compression, weight bearing lytic bony lesions, symptomatic local lesions.
- encourage to stop smoking.
- supportive care during chemotherapy.

Lung cancer (Histological classification)

Bronchogenic carcinomas of primary lung cancers can be classified as follows:

o Non small cell lung carcinomas (NSCLC) : This accounts for 70 -75% of bronchogenic carcinomas and can be further subdivided into:

§ Squamous cell carcinoma (25-30%)

§ Adenocarcinoma (30-35%)

§ Large cell carcinoma (10-15%)

o Small cell lung carcinoma (SCLC) : This chalks up 20 – 25% of bronchogenic carcinomas and comprises mainly of a group of cancers called oat cell carcinomas.

o Combined patterns : this consists of the various types of combinations of NSCLC and SCLC e.g. combined squamous & adenocarcinomas and combined squamous cell carcinomas & SCLC.

Lung cancer (Incidents and risk factors)

- Lung cancer accounts for around 19% of all cancers and 27% of cancer deaths.

- The incidence is increasing in women (due to the increase in women smokers).

- The major risk factor for lung cancer is cigarette smoking.

- Other risk factors:

o Passive smoking - being near smokers and inhaling the smoke which is being exhaled by smokers increases the risk to twice that of non-smokers.

o Heavy metal exposure - exposure / working with heavy metals e.g. nickel, chromium, vinyl chloride, arsenic for prolonged periods of time.

o Asbestos exposure - increases the risk of non-smokers by 5 fold & 55 times greater in smokers.

o Chronic Obstructive Pulmonary Disease (COPD) (check out my writings on COPD)

o Industrial carcinogens - products from factories that cause cancer e.g. chloromethyl ether.

o Lung scars - e.g. post-tuberculosis infection

o Air pollution - prolonged exposure

o Hereditary - genetic factors

Lung Cancer

- Lung cancers or lung neoplasms can be generally divided into 3 broad categories, namely:

• Primary lung cancer (where cancer develops in the lung tissue itself)
• Secondary lung cancer (due to deposits of cancer cells originating from other cancer organs)
• Mesothelioma (cancer of the layer of tissue (pleura) that surrounds the lung ) - not really a lung cancer per se.

- Primary lung cancers can be further classified into

• benign (cancers that do not spread to other organs)
• malignant (cancers that do spread)

- More than 20 bengin & malignant primary lung cancers have been identified & classified histologically.

- However, 90 - 95% of these lung cancers are bronchogenic carcinomas.

- About 5% are bronchial carcinoids and 2 - 5% are mesenchymal & other miscellaneous lung cancers.