Chapter 085. Neoplasms of the Lung (Part 12) doc

Chapter 085. Neoplasms of the Lung (Part 12) Non-Small Cell Lung Cancer NSCLC Stages I and II Surgery In patients with NSCLC stages IA, IB, IIA and IIB (Table 85-2) who can tolerate operation, the treatment of choice is pulmonary resection. If a complete resection is possible, the 5-year survival rate for N0 disease is about 60–80%, depending on the size of the tumor. The 5-year survival drops to about 50% when N1 (hilar node involvement) disease is present. The extent of resection is a matter of surgical judgment based on findings at exploration. Clinical trials have shown that lobectomy is superior to wedge resection in reducing the rate of local recurrence. Pneumonectomy is reserved for patients with tumors involving multiple lobes or very central tumors and should only be performed in patients with excellent pulmonary reserve. In addition, patients undergoing a right-sided pneumonectomy after induction chemotherapy and radiation therapy (see below) have a high mortality rate and should be carefully selected before surgery. Wedge resection and segmentectomy (potentially by VATS) are reserved for patients with poor pulmonary reserve and small peripheral lesions. Radiotherapy with Curative Intent Patients with stage I or II disease who refuse surgery or are not candidates for pulmonary resection should be considered for radiation therapy with curative intent. The decision to administer high-dose radiotherapy is based on the extent of disease and the volume of the chest that requires irradiation. Patients with distant metastases, malignant pleural effusion, or cardiac involvement are not considered candidates for curative radiation treatment. The long-term survival for patients with all stages of lung cancer who receive radiation with curative intent is about 20%. In addition to being potentially curative, radiotherapy may increase the quality and length of life by controlling the primary tumor and preventing symptoms related to local recurrence in the lung. Treatment with curative intent usually involves midplane doses of 60–64 Gy, while palliative thoracic radiation (see below) involves delivery of 30–45 Gy. The major dose-limiting concern is the amount of lung parenchyma and other organs in the thorax that are included in the treatment plan, including the spinal cord, heart, and esophagus. In patients with a major degree of underlying pulmonary disease, the treatment plan may have to be compromised because of the deleterious effects of radiation on pulmonary function. The most common side effect of curative thoracic radiation is esophagitis. Other side effects include fatigue, radiation myelitis (rare), and radiation pneumonitis, which can sometimes progress to pulmonary fibrosis. The risk of radiation pneumonitis is proportional to the radiation dose and the volume of lung in the field. The full clinical syndrome (dyspnea, fever, and radiographic infiltrate corresponding to the treatment port) occurs in 5% of cases and is treated with glucocorticoids. Acute radiation esophagitis occurs during treatment but is usually self-limited, unlike spinal cord injury, which may be permanent and should be avoided by careful treatment planning. Brachytherapy (local radiotherapy delivered by placing radioactive "seeds" in a catheter in the tumor bed) provides a way to give a high local dose while sparing surrounding normal tissue. NSCLC Stage IA Patients with resected stage IA NSCLC receive no other therapy but are at a high risk of recurrence (~2–3% annually) or developing a second primary lung cancer. Thus, it is reasonable to follow these patients with CT scans for the first 5 years and consider entering them onto early detection and chemoprevention studies. Adjuvant Chemotherapy for NSCLC Stages IB and II A meta-analysis of more than 4300 patients showed a trend toward improved survival of ~5% at 5 years with cisplatin-based adjuvant therapy (p = .08). Subsequently, three randomized studies demonstrated no significant survival advantage despite the addition of more "modern" postoperative adjuvant chemotherapy regimens. However, since then at least three additional randomized trials and two meta-analyses showed a survival benefit in response to postoperative adjuvant-based therapy (Table 85-5). Consequently, adjuvant chemotherapy is now routinely recommended in NSCLC patients with a good performance status and stage IIA or IIB disease, though the beneficial effects are modest. . Chapter 085. Neoplasms of the Lung (Part 12) Non-Small Cell Lung Cancer NSCLC Stages I and II Surgery In patients with NSCLC. doses of 60–64 Gy, while palliative thoracic radiation (see below) involves delivery of 30–45 Gy. The major dose-limiting concern is the amount of lung parenchyma and other organs in the thorax. sometimes progress to pulmonary fibrosis. The risk of radiation pneumonitis is proportional to the radiation dose and the volume of lung in the field. The full clinical syndrome (dyspnea, fever,