SEGMENTECTOMY MAY BE ENOUGH FOR STAGE I NSCLC

NEW YORK (Reuters Health) Nov 02 - In treatment of stage I non-small cell lung cancer (NSCLC), anatomic segmentectomy prevents locoregional recurrence as well as lobectomy, according to data presented yesterday afternoon at CHEST 2010, the annual international scientific assembly of the American College of Chest Physicians in Vancouver.

Wedge resection, on the other hand, provides inferior locoregional control, reported Dr. Matthew J. Schuchert, from the University of Pittsburgh Medical Center.

A parenchyma-sparing procedure, segmentectomy removes one of the 19 lung segments, each of which is supplied by a direct branch of a lobar bronchus and its accompanying pulmonary artery branch and separated from adjacent segments by connective tissue septa.

"For a segmentectomy, the surgeon ligates the bronchus and arterial branch that go to that segment, goes through the anatomic planes between segments, and takes out the whole segment" and its associated lymph nodes, Dr. Loren Harris explained to Reuters Health. "For a wedge resection, you basically grab a piece of the lung that includes the tumor and take a stapler across it."

Dr. Harris is spokesman for the American College of Chest Physicians and a cardiothoracic surgeon at Richmond University Medical Center in Staten Island, New York; he did not participate in the study.

Dr. Schuchert and colleagues reviewed outcomes for 1093 patients who underwent resection for clinical stage I NSCLC at their center between 2002 and 2009. Average age was 68 (range 22-99). While mean tumor size was 2.9 cm, the largest one removed was 23 cm.

A total of 235 patients had anatomic segmentectomy, 130 had wedge resection, and 728 had lobectomy.

During mean follow-up of 30.5 months, overall survival was similar in the three groups, although there was a trend toward reduced peri-operative mortality with segmentectomy compared with lobectomy (0.4% vs 1.8%, p = 0.12).

Locoregional recurrence was significantly higher in the wedge resection group (14.6%) than in the segmentectomy group (8.9%, p = 0.006). However, locoregional recurrence and recurrence-free survival were equivalent for segmentectomy and lobectomy.

The investigators note in their meeting abstract that pathological examination resulted in upstaging in 22.3% of patients. Nevertheless, the extent of resection didn't affect survival in this group.

"Sublobar resection, even for stage I lung cancer, has been viewed as a 'compromise procedure,' where results are not expected to be that good," Dr. Schuchert told Reuters Health. "That's why this (study) is exciting news because we have a lesser resection technique showing very good efficacy."

He noted that the surgeons decided which type of resection to perform, based primarily on tumor size and location.

"Small tumors and ones positioned in a discreet segment are the ones we strongly consider for segmentectomy," he said. "But if the tumor overlaps segments or is very central, segmentectomy may not be possible."

Other factors influencing surgery were pulmonary function, age, and a previous lobectomy.

Dr. Schuchert theorized that with a wedge resection, "we may be missing tumor cells within the lymphatic system or N1 lymph nodes that we would get with segmentectomy or lobectomy, which then pop up as locoregional recurrence later on."

"This study confirms mounting evidence showing that anatomic sublobectomy, including lymph node sampling or resections, provides similar results in early lung cancer," Dr. Harris said.

Still, he said, the equivalence of outcomes between the two procedures remains to be proven. "We don't want to jump the gun and offer a surgery that doesn't have same long term outcome," he added.

A national trial to compare segmentectomy and lobectomy is now enrolling patients. According to Dr. Schuchert, "Our findings underscore the need for centers around the country to participate in that trial so we can really answer this question with a well designed prospective study."