Role of Video-Assisted Thoracic Surgery (VATS) in Staging, Diagnosis and Treatment of Lung Cancer

Advances in the use of surgery and multimodality treatment for N2 non-small cell lung cancer

INTRODUCTION

Stage IIIA-N2 non-small cell lung cancer (NSCLC) represents a heterogeneous group of bronchogenic carcinomas with locoregional involvement. Different categories of N2 disease exist, ranging from unexpectedly encountered N2 involvement after detailed preoperative staging or 'surprise' N2, to potentially resectable disease treated within a combined modality setting, and finally, bulky N2 involvement treated by chemoradiation. Areas covered: Large randomised controlled trials and meta-analyses on stage IIIA-N2 NSCLC have been published but their implications for treatment remain a matter of debate. No definite recommendations can be provided as diagnostic and therapeutic algorithms vary according to local, national or international guidelines. Expert commentary: From the literature, it is clear that patients with stage IIIA-N2 NSCLC should be treated by combined modality therapy including chemotherapy, radiotherapy and surgery. The relative contribution of each modality has not been firmly established. For patients undergoing induction therapy, adequate restaging is important as only down-staged patients will clearly benefit from surgical resection. Each patient should be discussed within a multidisciplinary team to determine the best diagnostic and therapeutic approach according to the specific local expertise. In the near future, it might be expected that targeted therapies and immunotherapy will be incorporated as possible therapeutic options.

Surgery: therapeutic indications

Although never proven to be superior in a large, prospective randomized trial, surgical resection remains the treatment of choice for early stage non-small cell lung cancer (NSCLC). In stages IA, IB, IIA, IIB and resectable IIIA surgical treatment offers the best long-term prognosis when a complete resection can be performed. Standard operations include lobectomy, bilobectomy and pneumonectomy. Whenever possible, lobectomy is the procedure of choice. Lesser resections like segmentectomy or wedge excision are rarely indicated in primary NSCLC. Specific lung parenchyma saving operations include tracheo- and bronchoplastic procedures which are indicated in selected cases of centrally located NSCLC. Extended resections include removal of lung together with another organ or structure as thoracic wall, pericardium, diaphragm or superior sulcus. En bloc excision of the involved structure is advised. Accurate peroperative evaluation will determine the extent of resection and if possible, a pneumonectomy should be avoided because of its high mortality and morbidity rate. Surgical resection after induction therapy for early stage or locally advanced NSCLC is feasible, but is often more complex and carries a higher risk, especially when a right pneumonectomy has to be performed after induction chemoradiotherapy.

Remediastinoscopy after neoadjuvant therapy for non-small cell lung cancer

Despite technical difficulties due to mediastinal fibrosis, remediastinoscopy can be a valuable tool in the restaging of non-small cell lung cancer after neoadjuvant therapy. The aim of our study was to evaluate the feasibility, sensitivity and accuracy of remediastinoscopy. From November 1994 to July 2001 we performed a remediastinoscopy in 27 patients after neoadjuvant therapy. Their age ranged from 35 to 80 years (mean 61.9+/-11.9). In all 27 patients it was possible to perform a remediastinoscopy without major technical difficulties and take biopsies of the lymph nodes that were initially invaded by tumour. Remediastinoscopy was positive in 11 patients (40.7%) and negative in 16 (59.3%). In the 11 patients with a positive remediastinoscopy a complete resection was not judged possible and therefore, an unnecessary thoracotomy was avoided. In four patients, remediastinoscopy turned out to be false negative. So, in our series, sensitivity was 73%, specificity 100% and accuracy 85%. The positive and negative predictive values were 100 and 75%, respectively. Previous mediastinoscopy is no contra-indication for a repeat one after neoadjuvant therapy. Although sensitivity and accuracy are lower than that of a first mediastinoscopy, remediastinoscopy is useful to select patients for surgical resection after induction therapy.

Surgery for non-small cell lung cancer

Although never proven to be superior in a randomized trial, surgical resection remains the treatment of choice for early stage non-small cell lung cancer (NSCLC). In stages IA, IB, IIA, IIB and selected stages IIIA surgical treatment offers the best long-term prognosis when a complete resection can be performed. Standard operations include lobectomy, bilobectomy and pneumonectomy. Whenever possible, lobectomy is the procedure of choice. Lesser resections like segmentectomy or wedge excision are not indicated in primary NSCLC due to a higher local recurrence rate and poorer long-term survival. Specific lung parenchyma saving operations include tracheo- and bronchoplastic procedures which are indicated in selected cases of centrally located NSCLC. Extended resections include removal of lung together with another organ or structure as thoracic wall, pericardium, diaphragm or superior sulcus. En bloc excision of the involved structure is advised. Technically more demanding is lung resection after induction therapy, especially after combined chemoradiotherapy. A dense fibrotic reaction may render operative staging and dissection difficult. The precise, necessary extent of resection after induction therapy has not been determined yet. Although combined modality treatment has an overall increased morbidity and mortality rate, it may improve survival in selected cases of locally advanced NSCLC. Its precise role, however, still remains to be defined in large randomized trials.