Chapter 085. Neoplasms of the Lung (Part 12)

Non-Small Cell Lung CancerNSCLC Stages I and IISurgery 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...
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Chapter 085. Neoplasms of the Lung (Part 12) 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 cantolerate operation, the treatment of choice is pulmonary resection. If a completeresection 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% whenN1 (hilar node involvement) disease is present. The extent of resection is a matter of surgical judgment based on findings atexploration. Clinical trials have shown that lobectomy is superior to wedgeresection in reducing the rate of local recurrence. Pneumonectomy is reserved forpatients with tumors involving multiple lobes or very central tumors and shouldonly be performed in patients with excellent pulmonary reserve. In addition,patients undergoing a right-sided pneumonectomy after induction chemotherapyand radiation therapy (see below) have a high mortality rate and should becarefully selected before surgery. Wedge resection and segmentectomy(potentially by VATS) are reserved for patients with poor pulmonary reserve andsmall peripheral lesions. Radiotherapy with Curative Intent Patients with stage I or II disease who refuse surgery or are not candidatesfor pulmonary resection should be considered for radiation therapy with curativeintent. The decision to administer high-dose radiotherapy is based on the extent ofdisease and the volume of the chest that requires irradiation. Patients with distantmetastases, malignant pleural effusion, or cardiac involvement are not consideredcandidates for curative radiation treatment. The long-term survival for patientswith all stages of lung cancer who receive radiation with curative intent is about20%. In addition to being potentially curative, radiotherapy may increase thequality and length of life by controlling the primary tumor and preventingsymptoms related to local recurrence in the lung. Treatment with curative intent usually involves midplane doses of 60–64Gy, while palliative thoracic radiation (see below) involves delivery of 30–45 Gy.The major dose-limiting concern is the amount of lung parenchyma and otherorgans in the thorax that are included in the treatment plan, including the spinalcord, heart, and esophagus. In patients with a major degree of underlyingpulmonary disease, the treatment plan may have to be compromised because of thedeleterious 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 radiationpneumonitis, which can sometimes progress to pulmonary fibrosis. The risk ofradiation pneumonitis is proportional to the radiation dose and the volume of lungin the field. The full clinical syndrome (dyspnea, fever, and radiographic infiltratecorresponding to the treatment port) occurs in 5% of cases and is treated withglucocorticoids. Acute radiation esophagitis occurs during treatment but is usuallyself-limited, unlike spinal cord injury, which may be permanent and should beavoided by careful treatment planning. Brachytherapy (local radiotherapydelivered by placing radioactive seeds in a catheter in the tumor bed) provides away 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 ahigh risk of recurrence (~2–3% annually) or developing a second primary lungcancer. Thus, it is reasonable to follow these patients with CT scans for the first 5years and consider entering them onto early detection and chemopreventionstudies. Adjuvant Chemotherapy for NSCLC Stages IB and II A meta-analysis of more than 4300 patients showed a trend towardimproved survival of ~5% at 5 years with cisplatin-based adjuvant therapy (p =.08). Subsequently, three randomized studies demonstrated no significant survivaladvantage despite the addition of more modern postoperative adjuvantchemotherapy regimens. However, since then at least three additional randomizedtrials and two meta-analyses showed a survival benefit in response topostoperative adjuvant-based therapy (Table 85-5). Consequently, adjuvantchemotherapy is now routinely recommended in NSCLC patients with a goodperformance status and stage IIA or IIB disease, though the beneficial effects aremodest.