2015 Journal of Thoracic Oncology  
Backgrounds: The prognostic significance of additional lung nodules in the setting of lung cancer is important as the impact on survival is often considered for the justification of surgical selection in the management of patients with synchronous nodules. TNM 7 down staged the impact on T category but did not distinguish between second primary versus metastasis. Traditional distinctions such as the Martini criteria do not take the same histological type into account and classification
more » ... to improve (e.g. IASLC classification of adenocarcinoma). The aim of our study is to determine if it is possible to distinguish between second primary versus metastases in patients with the same histological type and quantity any difference in survival. Methods: We retrospectively analysed data from a prospectively collated database at our institution. We collected all the records which included two resected nodules. The detailed pathology reports of these patients were retrieved and the histology, subtype and pTNM of tumours documented. Slides were re-reviewed to determine the histological subtypes according to the current IASLC adenocarcinoma classification. Survival was calculated using Kaplan Meier methods and adjusted survival compared using Cox regression on R (statistical software). Results: From April 1999 to February 2013, a total of 2925 lung cancer resection were performed. Of these, 379 (14%) operations fulfilled the inclusion criteria of multiple nodules with 316 having synchronous tumours (83.3%) and 63 having metachronous tumours (16.6%). The tumours were ipsilateral in 87.3% and the vast majority were in the same lobe (70.9%). For synchronous tumours, patients with the same histological type had a poorer 5-years survival rate compared to tumours with different histology (p=0.041). The pathologist's designation between second primary versus intra-pulmonary metastasis distinguished between overall survival (p= 0.001) and this remained statistically significant in the tumours of the same cell type (p= 0.035). Figure 1. Survival outcomes between patients with multiple nodules classified as second primary versus intra-pulmonary metastasis Conclusion: Our results suggest that distinction between second primary and intrapulmonary metastasis remains important for staging as appreciable differences in survival were observed in patients with synchronous nodules. Survival was poorer in patients with multiple nodules of the same histologic type (compared to different histology) and within the same histological subtype it is possible for pathologists to distinguish between second primary and intra-pulmonary metastasis. As this is currently confirmed only on pathologic stage in the majority, it presently does not influence the selection for surgery. Background: The 7th TNM staging system for lung cancer recommended staging for cases with multiple nodules viewed as intrapulmonary metastases (IM) as T3 (same lobe), T4 (ipsilateral different lobe) and M1a (contralateral lobe), whilst those classified as separate primary tumours (SPTs) as T(x)NM where "x" is the number of primary tumours, either as a number or "m" for multiple. With an increase in patients presenting with multiple nodules, we sought to develop a set of criteria for c-staging on imaging and to determine the agreement between clinical and pathological staging in a cohort of resected lung cancers who had multiple nodules. Methods: In 2013 and 2014, there were a total of 48 consecutive cases with available imaging resected with multiple tumours, ranging from 2 to 5 nodules. Of these, one case was excluded as it was a carcinoid with background DIPNECH. These cases were classified as SPT or IM based on previously published criteria (Girard et al. Am J Surg Pathol 2009;33:1752-64). Imaging criteria were generated based on clinical experience in similar fashion with indicators of SPT being 1) Lesions of equivalent size (one not more than 100% of the
doi:10.1016/s1556-0864(16)30011-9 fatcat:nlhtgbimt5fu5dx4syerr2hjmu