Segmentectomy for Non-Small Cell Lung Cancer
The use of elective segmentectomy for medically fit patients has been a source of controversy for the past forty years. The 1995 Lung Cancer Study Group’s (LCSG) randomized trial solidified lobectomy as the standard of care in early stage non-small cell lung cancer (NSCLC). It was a well-conceived and executed trial, but its results now reflect a different era. In the past three decades, there has been an explosion in radiographic technology and understanding of tumor biology. These factors have changed the playing field in stage I NSCLC.
Subsequent retrospective series and population-based studies contradicted the LCSG results, demonstrating equivalent survival in well-selected, stage I patients undergoing segmentectomy. Furthermore, important prognostic factors have become increasingly apparent, including size <2cm, use of segmentectomy as opposed to non-anatomic wedge resection, adequacy of surgical margins, and use of lymph node dissection.
Two large prospective trials—similar in design to the LCSG trial but with updated staging and smaller size limits—finished recruitment. Namely, the first trial, JCOG0802/WJOG4607L, reported survival data in 2021. In this work there was a trend toward increased local recurrence in the segmentectomy arm. However, that group also experienced better overall survival at five years—a divergence from the LCSG findings. The second of these trials, CALGB/Alliance 140503, has yet to report its survival endpoints.
Segmentectomy will likely never be the appropriate resection for all stage IA NSCLC patients. But there is cohort present where this more tailored approach and associated preservation of the lungs is advantageous. Proper segmentectomy use is founded on basic surgical oncology principles, with use for small tumors, favorable histology, with adequate surgical margins, and proper evaluation of hilar and mediastinal lymph nodes. When selected appropriately, early stage NSCLC patients appear to have the potential for improved survival, dependent on thoughtful use of segmentectomy.
References
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2) Altorki NK, Wang X, Wigle D, Gu L, Darling G, Ashrafi AS, Landrenau R, Miller D, Liberman M, Jones DR, Keenan R, Conti M, Wright G, Veit LJ, Ramalingam SS, Kamel M, Pass HI, Mitchell JD, Stinchcombe T, Vokes E, Kohman LJ. Perioperative mortality and morbidity after sublobar versus lobar resection for early-stage non-small-cell lung cancer: post-hoc analysis of an international, randomised, phase 3 trial (CALGB/Alliance 140503). Lancet Respir Med. 2018 Dec;6(12):915-924. doi: 10.1016/S2213-2600(18)30411-9.
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