Segmented.

Top Line: Suggesting a sublobar resection for early-stage non-small cell lung cancer (NSCLC) has been a tumor board faux pas since 1995.

The Study: Importantly, “sublobar” is just what it sounds like, an umbrella term for resection of anything less than an entire lobe, including both segmentectomy (anatomic) and wedge (non-anatomic) resections. Nearly three decades later, JCOG0802 is resurrecting the concept of the more sophisticated segmentectomy for the lowest risk radiologically diagnosed NSCLC, an entity with a growing incidence amidst rising calls for screening high risk populations. This Japanese phase 3 trial randomized 1106 patients across 70 institutions to segmentectomy versus the current standard of lobectomy for peripheral (i.e., located in the outer-third of parenchyma) tumors up to 2 cm with radiographic consolidation no more than half the size of the tumor (denotes better prognosis). All patients received either a systematic (36%) or selective (64%) node dissection of hilar and mediastinal nodal stations—22/552 patients in the segmentectomy arm were converted to lobectomy upon intraop discovery of involved nodes or positive margins. The study was designed to assess non-inferiority and also potential superiority of overall survival in the experimental segmentectomy arm, and both were established with survival rates at 5 years of 94% after segmentectomy and 91% after lobectomy. While local recurrence was nearly twice as likely after segmentectomy (10.5%) than lobectomy (5.4%), event-free survival was a wash (88% either way) perhaps due to nearly double the number of non-cancer deaths after lobectomy (n=52) than after segmentectomy (n=27). Importantly, reasons for these excess non-cancer deaths remain quite unclear and not due to excessive respiratory decline, as specifically prospectively measured, following larger resections.

TBL: Opposed to conventional wisdom, large phase 3 data demonstrates improved survival with segmentectomy over lobectomy for low-risk peripheral stage IA NSCLC. | Saji, Lancet 2022