Assessing the prognostic impact of the International Association for the Study of Lung Cancer proposed definitions of complete, uncertain, and incomplete resection in non-small cell lung cancer surgery

- Controversy exists about the definition of complete resection in NSCLC surgery.
- Inconsistency in the prognostic impact of incomplete resection complicates matters.
- The IASLC proposed several criteria to define complete and incomplete resection.
- A third category of uncertain resection was added.
- IASLC definitions of complete, uncertain and incomplete resection predict survival.

ObjectiveThe aim of this study was to assess the prognostic impact of the definitions of complete, uncertain, and incomplete resection in non-small cell lung cancer (NSCLC) surgery, as proposed by the International Association for the Study of Lung Cancer (IASLC).Patients and methodsSingle institution retrospective study of consecutive patients undergoing surgery for NSCLC between 1998 and 2007. Complete resection was defined by absence of gross and microscopic residual disease; systematic nodal dissection; no extracapsular extension in distal lymph nodes; and negativity of the highest mediastinal node removed. An uncertain resection was defined by free resection margins, but one of the following applied: lymph node evaluation less rigorous than systematic nodal dissection; positivity of the highest mediastinal node removed; presence of carcinoma in situ at the bronchial margin; positive pleural lavage cytology. A resection was defined incomplete by presence of residual disease; extracapsular extension in distal lymph nodes; positive cytology of pleural or pericardial effusions. Follow-up was complete and all patients were followed up until death or for a minimum period of 5 years. Overall survival (OS) was analyzed using Kaplan-Meier method, log rank test, and Cox proportional hazards model.ResultsA total of 1277 patients were identified. One thousand and three patients (78.5%) underwent complete resection, 185 (14.5%) underwent uncertain resection, and 89 (7.0%) underwent incomplete resection. Both uncertain and incomplete resection were associated with significantly worse OS when compared with complete resection (hazard ratio: 1.69 and 3.18, respectively; both p = 0.0001). Median OS and 5-year survival rate were 80.1, 39.9, 17.3 months and 58.8%, 37.3%, 15.7% in patients undergoing complete, uncertain, and incomplete resection, respectively.ConclusionThe present analysis suggests that in patients undergoing surgery for NSCLC, the IASLC definitions of complete, uncertain, and incomplete resection are associated with statistically significant differences in survival.