Extent of Surgical Resection for Stage I and II Lung Cancer

Overview of the Evolution of Lung Cancer Surgery

Historically, lung cancer surgery has evolved so as to minimize the extent of parenchymal resection ( Fig. 29.2 ). Surgeons have been trying to achieve an optimal balance between radical surgery and surgery that preserves postoperative lung function. Kummel presented the earliest report, published in 1911, of a pneumonectomy of the right side; the patient was a 40-year-old man who died on the sixth postoperative day. After a series of early postoperative deaths after pneumonectomy in the 1920s, Evarts Graham Churchill in St. Louis, Missouri, reported the first successful pneumonectomy, using a tourniquet technique, on a 48-year-old male doctor with lung cancer in 1932. After this landmark operation, reports of successful pneumonectomies for lung cancer were presented by Rienhoff and Broyles, Alexander, Archibald, Sauerbruch, and Overholt. In 1940, Overholt reviewed 110 pneumonectomies, including his own 15 cases, for benign and malignant lung diseases and found a mortality rate of 65% for procedures performed for malignant disease. He noted that the operability of primary lung cancer was 25%. In the 1940s, pneumonectomy was established as the standard mode of pulmonary resection for lung cancer. Allison performed pneumonectomy with intrapericardial ligation of the pulmonary vessels, and more importantly, adding local–regional lymph node dissection to pneumonectomy was proposed as radical surgery for lung cancer. Cahan and coworkers called this procedure radical pneumonectomy, which indicated the combination of parenchymal resection and lymph node dissection.

In the 1950s and 1960s, lobectomy gradually replaced pneumonectomy. In 1950, Churchill et al. reported that the 5-year survival rate with lobectomy (19%) was better than that with pneumonectomy (12%). Belcher reported a 5-year survival rate after lobectomy of 61%, which was outstanding at that time. In 1960, Cahan again defined radical lobectomy as an operation in which one or two lobes of an entire lung are excised in a block dissection, along with certain regional hilar and mediastinal lymphatics ( Fig. 29.3 ). The extent of lymph node dissection was also defined according to the primary site of the lung cancer. Cahan analyzed the outcomes of 48 radical lobectomies for primary and metastatic lung cancers and concluded that survival for 5 or more years could be attributed in large part to radical lobectomy associated with more extensive lymphatic dissection. In the 1970s and 1980s, lobectomy was considered the standard mode of resection for primary lung cancer and pneumonectomy was no longer the standard approach.

Although lobectomy came to be considered the standard of care for primary lung cancer, lesser resections—segmentectomy and wedge resection—for peripheral lung cancer have always been reserved for patients who are not able to tolerate more extensive procedures such as lobectomy or pneumonectomy. Churchill and Belsey originally introduced segmental resection in 1939 as segmental pneumonectomy for the treatment of benign lung diseases. This technique was later advocated for use in patients who had operable lung cancer and limited pulmonary reserve. In 1972, Le Roux reported on 17 patients with peripheral tumors who had undergone segmental resection. In 1973, Jensik et al. suggested that anatomic pulmonary segmentectomy could be effectively applied to small primary lung cancers when the surgical margins were sufficient.

The results of some subsequent nonrandomized studies showed that excellent outcomes could be achieved with segmental resection for patients with early cancers. These reports stimulated a debate about the optimal resection technique for early-stage nonsmall cell lung cancer (NSCLC), which the Lung Cancer Study Group addressed in a prospective, randomized trial conducted with 247 patients with stage IA NSCLC. The investigators examined postoperative prognosis and pulmonary function after limited pulmonary resection, including anatomic segmentectomy and nonanatomic wide wedge resection, or lobectomy. They found a 75% increase in the recurrence rate ( p = 0.02) and a 30% increase in the overall death rate ( p = 0.08) for limited resection. With regard to pulmonary function, the investigators judged the follow-up and reporting to be somewhat unreliable because study funding was terminated early. The authors concluded that limited resection did not confer improved perioperative morbidity, mortality, or late postoperative pulmonary function. Because of the higher rates of death and local–regional recurrence associated with limited resection, lobectomy still must be considered the surgical procedure of choice for patients with peripheral T1 N0 NSCLC. Because this landmark trial is the only randomized trial in which limited resection was directly compared with lobectomy, the results are still considered valid.

In 2006 and 2011, Allen et al. and Darling et al. published results from a prospective, randomized trial—the American College of Surgery Oncology Group Z0030 study—designed to evaluate the prognostic significance of lymph node dissection in lung cancer. In this trial, systematic sampling was compared with lymph node dissection for N0 or nonhilar N1, T1, or T2 NSCLC (stage I and II). In short, the results of this study did not support a prognostic advantage of lymph node dissection over sampling. The authors concluded that if systematic and thorough presection sampling of the mediastinal and hilar lymph nodes is negative, mediastinal lymph node dissection does not improve survival for patients with early-stage NSCLC; the authors added that these results cannot be generalized to patients who have radiographic staging or higher-stage tumors.

On the basis of the results of these two important prospective studies, it is widely accepted that the present-day standard of care should be at least lobectomy with lymph node sampling or dissection for stage I and II lung cancer.