Lung cancer: a review

The frequency, risk factors, pathophysiology, diagnosis, and management of lung cancer are reviewed. An estimated 157,400 Americans died of lung cancer in 2001. Lung cancer is the second most frequent cancer in both men and women. The major risk factor for lung cancer is smoking, which accounts for 75-80% of lung cancer-related deaths. Lung cancers can be broadly classified into two forms, small-cell carcinomas and non-small-cell carcinomas. Non-small-cell lung cancer is more common, accounting for up to 75% of lung cancers. Lung cancer is diagnosed by chest radiography, sputum cytology, bronchoscopy, needle biopsy, and other techniques. Surgery plays a major role in managing stage I and stage II non-small-cell lung cancer and may be used for stage III disease. Patients with stage IIIa disease may be surgical candidates, but involvement of mediastinal lymph nodes reduces the probability of survival. Adjuvant irradiation may reduce the rate of local recurrence but does not increase survival time. Adjuvant chemotherapy may confer a small survival-time advantage if the regimen includes cisplatin. Chemotherapy combined with radiation therapy may produce a survival advantage over irradiation alone. Patients with advanced non-small-cell lung cancer should receive combination chemotherapy. Several regimens have shown a survival advantage over best supportive care. Paclitaxel, docetaxel, gemcitabine, vinorelbine, irinotecan, and topotecan have activity both as single agents and in combination. Surgery has only a limited role in the management of small-cell lung cancer. Patients with limited disease should receive a platinum-based chemotherapy regimen plus radiation therapy. Combination chemotherapy should be offered to patients with extensive disease. The most active regimens contain cisplatin or carboplatin. Paclitaxel, docetaxel, gemcitabine, vinorelbine, irinotecan, and topotecan combinations have shown some promise. Lung cancer, although highly preventable, is usually diagnosed at an incurable stage. Chemotherapy is playing an increasingly important role alongside surgery and radiation therapy in the management of this disease.