Lung Cancer Medical Treatment
In SCLC (small cell lung cancer), patients with limited disease at presentation (disease confined to one lung and its regional lymph nodes) are distinguished from those with extensive stage disease, which includes all cases not classified as limited. Limited stage disease, treated with radiation and chemotherapy (including prophylactic, or preventative, brain radiation therapy), will frequently have all evidence of disease disappear for a time and are said to enter remission. About 80% will relapse within 2 years, but as many as 10% to 15% may survive 5 or more years.
In extensive stage SCLC, response to chemotherapy and palliative radiation occurs less frequently, and survival beyond 2 years is rare. Median survival is about 13 months.
In NSCLC, non-small cell lung cancer, those patients deemed medically inoperable may be treated with curative intent with radiation therapy with 5-year survival in early stage disease from 10% to 25%.
In advanced stage, inoperable stages IIIB and IV NSCLC, treatment remains non-curative, but palliative radiation therapy and chemotherapy can provide meaningful symptom improvement and prolongation of life as compared to only supportive care.
The use of targeted therapies in NSCLC has been of increasing importance especially in adenocarcinoma of the lung. Agents with lower levels of toxicity and efficacy at least as good as chemotherapy have been identified which can be utilized in patients whose cancer cells show mutations in specific genes. In addition, the use of agents targeted to other features of lung cancer, such as tumor factors to recruit blood vessels to support their growth, have been developed and have proven advantageous in the palliative treatment of NSCLC.
Side effects of radiation therapy vary with the area being treated, the dose being given, and the type of radiation technique and equipment being used.
Side effects of chemotherapy again vary with the drug being given, the dose being used, and the patient's unique sensitivity to the type of chemotherapy selected. There are a wide variety of both chemotherapies and targeted agents that may be tried in these cases.
Finally, preventive or adjuvant chemotherapy, has been utilized in operable stages of NSCLC in an attempt to eradicate microscopic, hidden deposits of lung cancer that may have escaped prior to surgery, and remain undetectable for now but will cause relapse later if not killed. While not of proven use in stage I NSCLC, it does appear to be of potential benefit in stages II and IIIA disease.