[Place and role of the pleura in non-small cell lung cancer dissemination]

Abstract

Introduction: The pleural involvement (PLI) in non-small cell lung cancer (NSCLC) has a poor prognosis, even though it might be very heterogeneous.

Patients and methods: A multicentric retrospective descriptive study was performed over 2329 patients who were operated for NSCLC between 1979 and 2010. The patients with PLI were classified in P(Parietal)PLI and V(visceral)PLI and then each subdivided : VPLI to peripheric (VPLI-P) and fissural (VPLI-F) and PPLI to mediastinal (PPLI-M) and costal (PPLI-C). Characteristics and survival were compared between the subgroups as well as with patients without PLI (WPLI, n=1439).

Results: The sex-ratio was 2.8 (males: n=1713). The PLI patients were significantly younger, with a less sex-ratio, less R0 resections (96% versus 98.7%, P=0.000076), and less N0 (60% vs 70%, P<10(-6)) as their 5-year survival (45.7% vs 55.5%, P<10(-6)). The PLI was related to the size of NSCLC (P<10(-6)) and N2 involvement (P=0.0020). It was less frequent after neoadjuvant treatment (36.2% vs 39.1% P=0.03). In the VPLI-F or PPLI-M, pneumonectomies were more frequent (P<10(-6)). In VPLI-P (n=196/561), there were more pN1 and pN2 (P=0.0065) with a 5-year survival of 42.9% vs 54.4%, P=0.013. In multivariate analysis, the PLI was not an independent prognostic factor contrary to age, sex, type of resection, pT and pN.

Conclusion: The pleura play a major role in NSCLC dissemination. Its involvement affects pN, the type of surgical resection and justifies the use of neoadjuvant treatment.

Keywords: CBNPC; Chirurgie; Facteurs de survie; NSCLC; Pleura; Plèvre; Surgery; Survival.