Diagnostic and Interventional Imaging (2013) 94, 1063—1064
EDITORIAL
Management of lung nodules in 2013
Our understanding of the morphological features and natural history of both benign lung nodules and small lung cancers has improved as a result of all of the observational prospective and randomized studies on the annual use of low dose chest CT for early screening of lung cancer in at risk people (mostly smokers over 50 years old). Reports of these findings have been published over the last fifteen or so years and have led to the construction of international multidisciplinary consensus guidelines on the management of undefined lung nodules, which both reduce the number of monitoring CTs but at the same time avoid leaving a wholly operable lung cancer to progress [1—3]. It has been shown, for example, that a solid nodule with smooth outlines which is oval, lenticular or triangular in shape, is located in contact with a scissure, and is between 2.8 and 10.6 mm in size (average: 4.4 mm) is invariably not malignant and represents an intrapulmonary lymph node, even if it increases in size on repeat investigations and sometimes has a volume doubling time of under 400 days [4]. Conversely, it has now been fully recognized that a low-density ground glass nodule (5—20 mm in diameter) can remain completely stable for several months or years even though it represents a non- or poorly invasive adenocarcinoma [5]. An excellent review of current knowledge by Lederlin et al. on the natural history of small primary lung adenocarcinomas and the role of imaging to identify and define these is particularly welcomed in this edition [6]. The authors recall the rationale for the new international histological classification of primary lung adenocarcinomas, which is based on the natural history and prognostic findings, supported by anatomic-radiologic correlations [7]. They then summarize the results of the North American randomized study (NLST), which assesses the impact of early screening with annually repeated low dose chest CT screening on lung cancer mortality in at risk patients [8]. Finally, they provide a full analysis of the remaining uncertainties, which currently limit the appropriateness of implementing any organized screening process for lung cancer using annual low dose CT. The authors also review the management strategy for lung nodules and emphasize the importance of nodule volumetry which provides for more accurate measurements (reproducibility) than merely nodule diameter and enables the nodule volume doubling time to be calculated in the first follow-up scan [9,10]. Using the algorithm developed in the NELSON study, the authors recommend that all solid nodules with a volume doubling time of 400 days or more on the first review at 3 months should be considered to be benign [11]. Because of this, a single one year review confirming stability of the lesion would appear to be sufficient to definitively confirm that it is benign and reduce the number of CT repeats which were previously required in the Fleischner Society guidelines published in 2005 [1]. The authors suggest a conservative approach to partially solid nodules based on annual follow-up for 3 to 5 years when the solid component is less than 5 mm in size as these lesions histologically represent mini-invasive adenocarcinomas.
2211-5684/$ — see front matter © 2013 Published by Elsevier Masson SAS on behalf of the Éditions françaises de radiologie. http://dx.doi.org/10.1016/j.diii.2013.10.015
1064 Lederlin et al. also highlight the importance of the multidisciplinary team meeting for the management of nodules, which are very strongly suspected to be malignant from CT [6]. The decision as to whether or not to perform a transbronchial or transthoracic biopsy or positron emission tomography and the choice of optimal treatment (lobectomy followed by mediastinal lymph node clearance for a confirmed adenocarcinoma compared to segmentectomy, wedge resection or sub-segmentectomy for a non-solid nodule) is taken in this meeting. Despite all of the knowledge which has been gained which has optimized the management of nodules, summarized excellently in the article by Lederlin et al. [6], a number of uncertainties remain: do lesions of atypical adenomatous hyperplasia and in situ adenocarcinomas transform into invasive adenocarcinomas? Does this type of single lesion progress to multiple lesions? What is the role of biomarkers in identifying invasive adenocarcinomas? What would be the impact of measuring the solid and non-solid components of partially solid nodules in future revisions of the TNM classification to assess lung cancers? There is also undoubtedly a clear need to develop reliable quantitative methods to monitor non-solid and partially solid nodules.
Disclosure of interest The author declares that he has no conflicts of interest concerning this article.
Editorial [2] Naidich DP, Bankier AA, MacMahon H, et al. Recommendations for the management of subsolid pulmonary nodules detected at CT: a statement from the Fleischner Society. Radiology 2013;266:304—17. [3] Godoy MC, Naidich DP. Overview and strategic management of subsolid pulmonary nodules. J Thorac Imaging 2012;27: 240—8. [4] de Hoop B, van Ginneken B, Gieterra H, Prokop M. Pulmonary perifissural nodules on CT scans: rapid growth is not a predictor of malignancy. Radiology 2012;265:611—6. [5] Suzuki K, Kolke T, Asakawa T, et al. A prospective radiological study of thin-section computed tomography to predict pathological noninvasiveness in peripheral clinical IA lung cancer (Japan Clinical Oncology Group, 2011). J Thorac Oncol 2011;6:751—6. [6] Lederlin M, Revel MP, Khalil A, et al. Management strategy of pulmonary nodule in 2013. Diagn Interv Imaging 2013. [7] Travis MD, Brambilla E, Noguchi M, et al. International association for the study of lung cancer/American Thoracic Society/European Respiratory Society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol 2011;6:244—85. [8] Aberle DR, Adams AM, Berg CD, et al. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med 2011;365:395—409. [9] Revel MP, Lefort C, Bissery A, et al. Pulmonary nodules: preliminary experience with three-dimensional evaluation. Radiology 2004;231:59—466. [10] Gavrielides MA, Kinnard LM, Myers K, Petrick N. Noncalcified lung nodules: volumetric assessment with thoracic CT. Radiology 2009;251:26—37. [11] Van Klaveren RJ, Oudkerk M, Prokop M, et al. Management of lung nodules detected by volume CT scanning. N Engl J Med 2009;361:2221—9.
References P.A. Grenier [1] MacMahon H, Austin JH, Gamsu G, et al. Guidelines for management of small pulmonary nodules detected on CT scans: a statement from the Fleischner Society. Radiology 2005;237:395—400.
Pitié-Salpêtrière Hospital Group, AP—HP, Paris 6 University, 75013 Paris, France E-mail address: [email protected]
EDITORIAL
Management of lung nodules in 2013
Our understanding of the morphological features and natural history of both benign lung nodules and small lung cancers has improved as a result of all of the observational prospective and randomized studies on the annual use of low dose chest CT for early screening of lung cancer in at risk people (mostly smokers over 50 years old). Reports of these findings have been published over the last fifteen or so years and have led to the construction of international multidisciplinary consensus guidelines on the management of undefined lung nodules, which both reduce the number of monitoring CTs but at the same time avoid leaving a wholly operable lung cancer to progress [1—3]. It has been shown, for example, that a solid nodule with smooth outlines which is oval, lenticular or triangular in shape, is located in contact with a scissure, and is between 2.8 and 10.6 mm in size (average: 4.4 mm) is invariably not malignant and represents an intrapulmonary lymph node, even if it increases in size on repeat investigations and sometimes has a volume doubling time of under 400 days [4]. Conversely, it has now been fully recognized that a low-density ground glass nodule (5—20 mm in diameter) can remain completely stable for several months or years even though it represents a non- or poorly invasive adenocarcinoma [5]. An excellent review of current knowledge by Lederlin et al. on the natural history of small primary lung adenocarcinomas and the role of imaging to identify and define these is particularly welcomed in this edition [6]. The authors recall the rationale for the new international histological classification of primary lung adenocarcinomas, which is based on the natural history and prognostic findings, supported by anatomic-radiologic correlations [7]. They then summarize the results of the North American randomized study (NLST), which assesses the impact of early screening with annually repeated low dose chest CT screening on lung cancer mortality in at risk patients [8]. Finally, they provide a full analysis of the remaining uncertainties, which currently limit the appropriateness of implementing any organized screening process for lung cancer using annual low dose CT. The authors also review the management strategy for lung nodules and emphasize the importance of nodule volumetry which provides for more accurate measurements (reproducibility) than merely nodule diameter and enables the nodule volume doubling time to be calculated in the first follow-up scan [9,10]. Using the algorithm developed in the NELSON study, the authors recommend that all solid nodules with a volume doubling time of 400 days or more on the first review at 3 months should be considered to be benign [11]. Because of this, a single one year review confirming stability of the lesion would appear to be sufficient to definitively confirm that it is benign and reduce the number of CT repeats which were previously required in the Fleischner Society guidelines published in 2005 [1]. The authors suggest a conservative approach to partially solid nodules based on annual follow-up for 3 to 5 years when the solid component is less than 5 mm in size as these lesions histologically represent mini-invasive adenocarcinomas.
2211-5684/$ — see front matter © 2013 Published by Elsevier Masson SAS on behalf of the Éditions françaises de radiologie. http://dx.doi.org/10.1016/j.diii.2013.10.015
1064 Lederlin et al. also highlight the importance of the multidisciplinary team meeting for the management of nodules, which are very strongly suspected to be malignant from CT [6]. The decision as to whether or not to perform a transbronchial or transthoracic biopsy or positron emission tomography and the choice of optimal treatment (lobectomy followed by mediastinal lymph node clearance for a confirmed adenocarcinoma compared to segmentectomy, wedge resection or sub-segmentectomy for a non-solid nodule) is taken in this meeting. Despite all of the knowledge which has been gained which has optimized the management of nodules, summarized excellently in the article by Lederlin et al. [6], a number of uncertainties remain: do lesions of atypical adenomatous hyperplasia and in situ adenocarcinomas transform into invasive adenocarcinomas? Does this type of single lesion progress to multiple lesions? What is the role of biomarkers in identifying invasive adenocarcinomas? What would be the impact of measuring the solid and non-solid components of partially solid nodules in future revisions of the TNM classification to assess lung cancers? There is also undoubtedly a clear need to develop reliable quantitative methods to monitor non-solid and partially solid nodules.
Disclosure of interest The author declares that he has no conflicts of interest concerning this article.
Editorial [2] Naidich DP, Bankier AA, MacMahon H, et al. Recommendations for the management of subsolid pulmonary nodules detected at CT: a statement from the Fleischner Society. Radiology 2013;266:304—17. [3] Godoy MC, Naidich DP. Overview and strategic management of subsolid pulmonary nodules. J Thorac Imaging 2012;27: 240—8. [4] de Hoop B, van Ginneken B, Gieterra H, Prokop M. Pulmonary perifissural nodules on CT scans: rapid growth is not a predictor of malignancy. Radiology 2012;265:611—6. [5] Suzuki K, Kolke T, Asakawa T, et al. A prospective radiological study of thin-section computed tomography to predict pathological noninvasiveness in peripheral clinical IA lung cancer (Japan Clinical Oncology Group, 2011). J Thorac Oncol 2011;6:751—6. [6] Lederlin M, Revel MP, Khalil A, et al. Management strategy of pulmonary nodule in 2013. Diagn Interv Imaging 2013. [7] Travis MD, Brambilla E, Noguchi M, et al. International association for the study of lung cancer/American Thoracic Society/European Respiratory Society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol 2011;6:244—85. [8] Aberle DR, Adams AM, Berg CD, et al. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med 2011;365:395—409. [9] Revel MP, Lefort C, Bissery A, et al. Pulmonary nodules: preliminary experience with three-dimensional evaluation. Radiology 2004;231:59—466. [10] Gavrielides MA, Kinnard LM, Myers K, Petrick N. Noncalcified lung nodules: volumetric assessment with thoracic CT. Radiology 2009;251:26—37. [11] Van Klaveren RJ, Oudkerk M, Prokop M, et al. Management of lung nodules detected by volume CT scanning. N Engl J Med 2009;361:2221—9.
References P.A. Grenier [1] MacMahon H, Austin JH, Gamsu G, et al. Guidelines for management of small pulmonary nodules detected on CT scans: a statement from the Fleischner Society. Radiology 2005;237:395—400.
Pitié-Salpêtrière Hospital Group, AP—HP, Paris 6 University, 75013 Paris, France E-mail address: [email protected]
