Invited commentary

Abstract

Few studies in the past 10 years have sought to address the interesting question of synchronous primary multiple lung cancer (SPMLC), and they have, for the most part, been retrospective studies focusing on this increasing clinical occurrence and its practical approach. However, very little is known to date about the proportion of patients who actually experience a SPMLC, especially those who would benefit from a surgical resection. The study by Rostad and associates [1Rostad H. Strand T.-E. Naalsund A. Norstein J. Resected synchronous primary malignant lung tumors: a population-based study.Ann Thorac Surg. 2008; 85: 204-210Abstract Full Text Full Text PDF PubMed Scopus (57) Google Scholar] contributes to our understanding of SPMLC outcomes. They assessed clinical characteristics, short-term and long-term survival in a register population-based study and found that from a total of 15,308 patients diagnosed with lung cancer in Norway, 2,528 underwent resection and 94 had SPMLC. Among these 94 patients, 66 had two SPMLCs and the remaining 28 had three or more. In 85 cases the tumors were of similar histology, mostly adenocarcinomas. In more than 80% of the patients, the tumors were diagnosed perioperatively or in the resected specimen. Furthermore, 5-year survival was 23.2% in patients with adenocarcinomas, 31.4% in those with squamous cell carcinomas, and 42.7% in those with tumors of other histologies (2 carcinoids), which were not fully consistent with previously published studies, as acknowledged by the authors. Finally, they concluded that patients who experience SPMLC should not be excluded from surgery because their survival is acceptable when compared with historic reports on patients with distant metastases or variants of T4 tumors. The SPMLC is still ambiguously assessed by the TNM staging system, which classifies this clinical situation either as a locally advanced disease, when tumors are located within the same lobe, or as a metastatic tumor in the other cases (ie, it scales this condition in “nonsurgical” stages IIIB and IV). Yet long-term survival after resection for SPMLC has been reported to be better than long-term survival in patients with tumors classified as stage IIIB and especially IV, for reasons other than a synchronous tumor. Moreover, there are intriguing, but intuitively realistic, data showing that the survival of SPMLC patients is quite similar to that of stage I disease patients [2Battafarano R.J. Meyers B.F. Guthrie T.J. Cooper J.D. Patterson A. Surgical resection of multifocal non-small cell lung cancer is associated with prolonged survival.Ann Thorac Surg. 2002; 74: 988-994Abstract Full Text Full Text PDF PubMed Scopus (105) Google Scholar]. Herein is the merit and strength of the current article, which advocates the possibility of an aggressive surgical approach with a curative objective. A second interesting question concerns the accuracy with which SPMLC is currently diagnosed. Hopefully progress in technology (ie, with the widespread use of early detection tools, such as multi-slice spiral computed tomography, fluorescence endoscopy, and positron emission tomographic scanning) will improve preoperative diagnosis accuracy and consequently avoid overlooking a possible curative treatment for the patient. However, in the absence of easily available genetic or molecular markers, differentiation between SPMLC and isolated pulmonary metastasis will remain difficult in the clinical setting and certainly lead to controversy regarding multidisciplinary management. In the near future, the use of genomic strategy may be the clue not only to refining prognosis and predicting recurrence more accurately, but also to altering decisions regarding the use of targeted therapeutics [3Potti A. Mukherjee S. Petersen R. et al.A genomic strategy to refine prognosis in early-stage non-small cell lung cancer.N Engl J Med. 2006; 355: 570-580Crossref PubMed Scopus (527) Google Scholar, 4Larsen J.E. Pavey S.J. Passmore L.H. Bowman R.V. Hayward N.K. Fong K.M. Gene expression signature predicts recurrence in lung adenocarcinoma.Clin Cancer Res. 2007; 13: 2946-2954Crossref PubMed Scopus (98) Google Scholar]. In the meantime, Rostad and associates [1Rostad H. Strand T.-E. Naalsund A. Norstein J. Resected synchronous primary malignant lung tumors: a population-based study.Ann Thorac Surg. 2008; 85: 204-210Abstract Full Text Full Text PDF PubMed Scopus (57) Google Scholar] are to be congratulated on their contribution to this area. Their results will certainly prove to be most beneficial to the thoracic surgery community. Resected Synchronous Primary Malignant Lung Tumors: A Population-Based StudyThe Annals of Thoracic SurgeryVol. 85Issue 1PreviewSynchronous lung tumors with a histology indicating primary lung carcinomas detected preoperatively or at surgery may represent intrapulmonary metastases from a primary tumor or two or more simultaneously occurring primary tumors. The situation is rare. This study was conducted to assess the characteristics and outcome for this patient group. Full-Text PDF