Surgery is usually only an option in non-small cell lung cancer (NSCLC) and if the disease is limited to one lung and has not spread beyond its confines. This is assessed with medical imaging (computed tomography, positron emission tomography). Furthermore, as stated, a sufficient respiratory reserve needs to be present to allow for the removal of lung tissue. Procedures performed include lobectomy (removal of one lobe), bilobectomy (two lobes) or pneumonectomy (removal of a whole lung). Smaller resections include wedge excision or segmentectomy (part of a lobe).
The role of sub lobar resection (extended wedge resection) continues to be debated for the primary management of NSCLC. Although overall survival appears to be equivalent to that of lobectomy resection, the local recurrence rate has been documented to be over three times more common (19% compared to 5%). Accordingly, sub lobar resection has historically been used as a "compromise resection" approach for the management of small (less than 3 centimeters diameter) stage I peripheral NSCLC identified in patients with impaired cardiopulmonary reserve. Recent reports of the use of intraoperative radioactive iodine brachytherapy implants at the margins of sublobar resection suggest that local recurrence can be reduced to that of lobectomy when this is used as a surgical adjunct to sublobar resection.
The role of anatomic segmentectomy (a larger sublobar resection) with complete lymph node staging has also been found to have potential survival benefits similar to lobectomy. Such resections should be limited to peripheral small (less than 2 cm diameter) stage I NSCLC where a margin of resection equivalent to the diameter of the tumour can be achieved.
Five-year prognosis is often as good as 70% following complete resection of limited (lesions limited to the lung tissue without lymph node spread - stage I) disease.
After surgery, adjuvant chemotherapy may be recommended if lymph nodes within the lung tissues resected (stage II) or the mediastinum (lymph nodes in the peri-tracheal region, stage III) are found to be positive for cancer spread. Survival may be improved by up to 15% above patients receiving only surgical resection in these circumstances. The role of adjuvant chemotherapy for patients with large stage I NSCLC (tumour diameter greater than 3 cm without lymph node involvement, stage IB) remains controversial.
Trials of preoperative chemotherapy in resectable NSCLC have been inconclusive[20].
The NCI Canada study JBR.10 treated patients with stage IB to IIB NSCLC with vinorelbine and cisplatin chemotherapy and showed a significant survival benefit of 15% over 5 years. However subgroup analysis of patients in stage IB showed that chemotherapy did not result in any survival gain in them. Similarly, while the Italian ANITA study showed a survival benefit of 8% over 5 years with vinorelbine and cisplatin chemotherapy in stages 1B to 3A patients, subgroup analysis also showed no benefit in the IB stage.
The Cancer and Leukemia Group B (CALGB) study was a randomized study which examined the use of carboplatin and paclitaxel chemotherapy in patients with stage 1B disease. Unfortunately, although initial results in 2004 were encouraging, an update at the recent American Society of Clinical Oncology meeting (June 2006) reported that the findings are now negative with no survival advantage with the use of adjuvant chemotherapy in patients with this stage of disease. However, exploratory analysis of patients in the CALGB study suggested that perhaps those with tumours equal or greater than 4 cm in size may still benefit.
At present, it is standard practice to offer patients with resected stage II-IIIA NSCLC adjuvant third generation platinum-based chemotherapy (e.g. cisplatin and vinorelbine). Adjuvant chemotherapy for patients with stage 1B remains controversial as clinical trials have not clearly demonstrated a survival benefit.
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