Chapter 085. Neoplasms of the Lung (Part 14)

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Superior Sulcus or Pancoast Tumors Non-small cell carcinomas of the superior pulmonary sulcus producing Pancoast's syndrome appear to behave differently than lung cancers at other sites and are usually treated with combined radiotherapy and surgery. Patients with these carcinomas should have the usual preoperative staging procedures, including mediastinoscopy and CT and PET scans, to determine tumor extent and a neurologic examination (and sometimes nerve conduction studies) to document involvement or impingement of nerves in the region. If mediastinoscopy is negative, curative approaches may be used in treating Pancoast's syndrome despite its apparent locally invasive nature. ...

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Chapter 085. Neoplasms of the Lung (Part 14) Superior Sulcus or Pancoast Tumors Non-small cell carcinomas of the superior pulmonary sulcus producing Pancoast's syndrome appear to behave differently than lung cancers at other sites and are usually treated with combined radiotherapy and surgery. Patients with these carcinomas should have the usual preoperative staging procedures, including mediastinoscopy and CT and PET scans, to determine tumor extent and a neurologic examination (and sometimes nerve conduction studies) to document involvement or impingement of nerves in the region. If mediastinoscopy is negative, curative approaches may be used in treating Pancoast's syndrome despite its apparent locally invasive nature. The best results reported thus employed concurrent preoperative irradiation [30 Gy in 10 treatments] and cisplatin and etoposide, followed by an en bloc resection of the tumor and involved chest wall 3–6 weeks later; 65% of thoracotomy specimens showed either a complete
response or minimal residual microscopic disease on pathologic evaluation. The 2- year survival rate was 55% for all eligible patients and 70% for patients who had a complete resection. NSCLC with T3, N0 Disease (Stage IIB) The subset of T3, N0 disease (which does not present as Pancoast tumor) was initially considered stage III disease. However, it has a different natural history and treatment strategy than stage III N2 disease and is now considered as stage IIB. Patients with peripheral chest wall invasion should have resection of the involved ribs and underlying lung. Chest wall defects are then repaired with chest wall musculature or Marlex mesh and methylmethacrylate. Five-year survival rates as high as 35–50% have been found, and adjuvant chemotherapy is usually recommended. NSCLC Stage III Treatment of locally advanced NSCLC is one of the most controversial issues in the management of lung cancer. Treatment options include a local therapy (surgery or radiation therapy) combined with systemic chemotherapy to control micrometastases. Interpretation of the results of clinical trials involving patients with locally advanced disease has been clouded by a number of issues, including changing diagnostic techniques, different staging systems, and heterogeneous patient populations with tumors that range from nonbulky stage
IIIA (clinical N1 nodes with N2 nodes discovered only at the time of surgery, despite a negative mediastinoscopy) to bulky N2 nodes (enlarged adenopathy clearly visible on chest x-rays or multiple nodal level involvement) to clearly inoperable stage IIIB disease. Thus, a team approach involving pulmonary medicine, thoracic surgery, and medical and radiation oncology is essential for the management of these patients. NSCLC Stage IIIA Nonbulky IIIASurgery for N2 disease is a controversial area in the management of lung cancer. Patients with N2 disease can be divided into "minimal" disease (involvement of only one node with microscopic foci, usually discovered at thoracotomy or mediastinoscopy) and the more common "advanced" bulky disease, clinically obvious on CT scans and discovered preoperatively. Patients who have an incidental finding of N2 disease at the time of resection should receive adjuvant chemotherapy. Bulky IIIA No evidence suggests that patients with "bulky," multilevel ipsilateral mediastinal nodes (N2) have improved survival with surgery and either pre- or postoperative chemotherapy compared to treatment with chemotherapy plus radiation therapy. This important issue was addressed in the multicenter randomized Intergroup 0139 Trial involving patients with pathologically staged
N2 disease who received 45 Gy of induction radiation therapy plus two cycles of cisplatin and etoposide to "debulk" tumors. The patients were then randomly assigned to surgical resection of any residual tumor or to boost radiation therapy plus an additional two cycles of chemotherapy. Although a significant improvement in progression-free survival was observed at 5 years for those patients randomized to surgical resection (22% vs. 11%; p = .017), the difference in 5-year overall survival while favoring surgery (22% vs. 11%; p = .10) was not significant. This is important since treatment-related mortality was greater in the surgery arm (8% vs. 2%), with the majority of deaths occurring in patients undergoing pneumonectomy. Patients who had persistent N2 disease following neoadjuvant chemotherapy did particularly poorly, leading some oncologists to conclude that surgery for bulky IIIA disease should only be conducted in patients who have clearing of their mediastinal nodes following neoadjuvant therapy. The main role of neoadjuvant chemotherapy is to control micrometastatic disease, and if this macroscopically evident disease is not sensitive to chemotherapy, it is unlikely that the microscopic disease will be controlled. Thus, surgical removal of the primary tumor after such chemotherapy is probably fruitless. Likewise, neoadjuvant chemotherapy generally should not be used to render inoperable disease operable. One exception to this approach is T4, N0 or T4, N1 (stage IIIB, see below) disease for which preoperative chemotherapy may provide enough tumor debulking to allow otherwise unresectable disease to be resected.
Chemotherapy may allow chest wall resection for direct extension of tumor, tracheal sleeve pneumonectomy, and sleeve lobectomy for lesions near the carina.