Radiation Therapy Preferable to Surgery for Stage IIIA Non-Small Cell LungCancer
Researchers at the 11th Annual World Conference on Lung Cancer recently presented results of a study finding that surgery after chemotherapy was not superior to radiation therapy after chemotherapy for treatment of patients with stage IIIA NSCLC .
Lung cancer is the leading cause of cancer-related deaths in the United States and Europe. The most common type of lung cancer, NSCLC, is a malignancy that arises from the tissues of the lung. Under most circumstances, NSCLC is not curable unless treated in early stages with surgery or radiation therapy. Current treatments attempt to destroy cancer cells or prevent further tumor growth. They include surgery, chemotherapy and radiation.
After lung cancer is diagnosed, the stage of cancer must be determined. There are several possible stages, each of which describes how far the cancer has spread. This staging system is important because treatments are often based on the stage of the disease. Stage IIIA NSCLC is a single cancer mass that is not invading any adjacent organs and involves one or more lymph nodes away from the primary cancer. Stage IIIA cancers are further subdivided into N1 and N2 subgroups. N1 cancers involve lymph nodes farther away from the mediastinum and are easier to remove with surgery. N2 cancers involve lymph nodes in the mediastinum and may be difficult to remove surgically. When Stage IIIA NSCLC cancer is diagnosed, it means the cancer has spread locally to the lymph nodes in the chest and may have already spread to other locations in the body, but is not detectable with current diagnostic tests. This means that treatment is directed at both destroying the cancer at and near its site of origin and at destroying cancer cells that may have spread to other locations in the body.
In the 1970s and 1980s, the standard treatment of stage IIIA cancers was radiation therapy or surgery in selected patients with minimal involvement of the lymph nodes. However, 80 to 90 percent of patients developed recurrence of their cancer following either of these treatments. Optimal treatment of patients with stage IIIA lung cancer is now known to require more than one therapeutic approach.
Administering chemotherapy and radiation therapy together (concurrently) appears to kill more cancer cells than administering them sequentially. Clinical trials have also demonstrated that neoadjuvant chemotherapy with radiation therapy can shrink stage III cancers allowing surgical removal of the remaining cancer. Patients with IIIA NSCLC receiving chemotherapy, surgery and radiation therapy have had an approximate 20 percent 5-year survival rate. Unfortunately, approximately 10 percent of these patients have died from side effects of treatment, mostly resulting from complications of surgery.
Thus, controversy continues regarding the best treatment for patients diagnosed with locally advanced stage IIIA NSCLC. The current study involved 579 patients diagnosed with stage IIIA NSCLC. Each patient received three cycles of platinum-based chemotherapy. The patients who responded to chemotherapy were then randomized to receive either surgery with the option of radiation or radiation alone. Results of the study indicate that 62 percent of the patients responded to chemotherapy, with 4 percent achieving a complete response. Of the 333 patients who had responded to chemotherapy, 308 were eligible to continue on the study, 154 patients received surgery and 154 received radiation. The 5-year overall survival rate was 17.5 percent among the radiation patients compared to 16.4 percent for the patients who underwent surgery. The disease-free period was slightly longer among the patients who had received radiation: 11.3 months versus 9.9 months for the surgical group. Of the surgical patients, 50 percent had complete surgical resection, although there was a 4-percent mortality rate. Additionally, 27 percent went on to receive postoperative radiation therapy. Overall, the patients who had surgery did significantly worse at 5 years.
Researchers concluded that, although initial chemotherapy for the treatment of NSCLC produces few complete responses, the response rates are significant. Surgery following chemotherapy does not improve the outcome of patients in stage IIIA NSCLC compared to surgery alone. For these reasons, chemotherapy and radiation therapy remain the standard of care for patients with IIIA NSCLC. Patients are encouraged to speak to their physician regarding treatment options for their specific situation.
Reference: van Meerbeeck J, et al. A Randomised Trial of Radical Surgery Versus Thoracic Radiotherapy After Response to Induction Chemotherapy in Patients With Histo-/Cytologically Proven Irresectable Stage IIIA-N2 NSCLC (EORTC 08941). Abstract Pr5. Proceedings from the 11th World Conference on Lung Cancer. July 2005.
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