Reply to the Editor

Abstract

We are grateful for the letter we received from Baisi and colleagues regarding our study1Mimae T. Tsutani Y. Miyata Y. Yoshiya T. Ibuki Y. Kushitani K. et al.Role of lymphatic invasion in the prognosis of patients with clinical node-negative and pathologic node-positive lung adenocarcinoma.J Thorac Cardiovasc Surg. 2014; 147: 1820-1826Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar and delighted by their thoughtful insight into our results. As they described in the letter, the main point of our study was that lymphatic invasion (LI) is a predictive prognostic factor in patients with pN(+) and pN(−) clinical T1N0 lung adenocarcinoma. In addition, the recurrence-free survival curves of pN(+) LI(−) and pN(−) LI(+) tumors did not significantly differ. Thus, not only pN(+) LI(−/+), but also pN(−) LI(+) might indicate the presence of micrometastases. A pN(−) LI(+) lung adenocarcinoma does not always strictly correspond to localized disease. Therefore, patients with pN(−) and LI(+) tumors should be considered candidates for adjuvant therapy. The suggestion about the role of LI status in the choice of surgical strategy is important. Although both wedge resection and segmentectomy are classified as limited resection, segmentectomy differs from wedge resection with respect to lymph node dissection, which can proceed during radical segmentectomy, but not wedge resection.2Okada M. Radical sublobar resection for small-diameter lung cancers.Thorac Surg Clin. 2013; 23: 301-311Abstract Full Text Full Text PDF PubMed Scopus (14) Google Scholar Anatomic segmentectomy with lymph node dissection and an adequate surgical margin is considered curative for clinical T1aN0 and pathologic N(−) LI(−/+) peripheral lung tumors. We proposed pN0 criteria that included solid tumors ≤0.8 cm and a maximum standardized uptake value of ≤1.5.3Tsutani Y. Miyata Y. Nakayama H. Okumura S. Adachi S. Yoshimura M. et al.Prediction of pathologic node-negative clinical stage IA lung adenocarcinoma for optimal candidates undergoing sublobar resection.J Thorac Cardiovasc Surg. 2012; 144: 1365-1371Abstract Full Text Full Text PDF PubMed Scopus (103) Google Scholar Solitary peripheral lung lesions with preoperative radiographic findings that meet the criteria can be cured by segmentectomy with lymph node dissection. In contrast, wedge resection and segmentectomy with adequate margins and without lymph node dissection are considered curative for clinical T1aN0 and pathologic N(−) LI(−) peripheral lung lesions. However, LI(−) status cannot be proved before or during surgery. Thus, preoperative radiographic findings for predicting LI status are needed to establish the optimal criteria for limited resection without lymph node dissection. In addition, because recent studies have shown that histologic subtypes correspond to the malignant aggressiveness of lung adenocarcinoma,4Okada M. Subtyping lung adenocarcinoma according to the novel 2011 IASLC/ATS/ERS classification: correlation with patient prognosis.Thorac Surg Clin. 2013; 23: 179-186Abstract Full Text Full Text PDF PubMed Scopus (30) Google Scholar the criteria for limited resection with and without lymph node dissection should also include the preoperative findings for predicting histologic subtypes. From our findings, we believe the optimal surgical strategy for cT1N0M0 adenocarcinomas should be determined by considering LI, lymph node status, and histologic subtypes. The identification of predictors for these factors is essential. The role of lymphatic invasion in the management of patients with T1N0M0 pulmonary adenocarcinomaThe Journal of Thoracic and Cardiovascular SurgeryVol. 148Issue 4PreviewWe read with interest the article by Mimae and colleagues1 about the role of the lymphatic invasion (LI) at specimen examination in predicting prognosis in patients with clinically assessed T1N0M0 lung adenocarcinoma. Full-Text PDF Open Archive