PET/CT and contrast enhancement CT (CECT) are the two fundamental non-invasive exams in the preoperative staging of patients with non small cell lung cancer (NSCLC). In the staging of the mediastinum, recent studies show that PET is more accurate than CECT, with an average sensitivity and specificity of 85 vs. 61% and 90 vs. 79%, respectively. However, thanks to its specificity value of 100%, the gold standard remains the mediastinoscopy. The aim of this study was to evaluate the PET/CT accuracy in the intrathoracic lymph node staging. Three hundred and five consecutive patients with proven or suspected non-small cell lung cancer who had an integrated PET/CT study were retrospectively evaluated. Lymph node staging was pathologically confirmed on tissue specimens obtained at surgery. A medline research of papers on accuracy of integrated PET/CT in lymph node staging was also carried out. In this population of patients, a total of 1972 lymph node stations were evaluated. Integrated PET/CT correctly staged 247 out of 305 patients: 188 of 214 (87.8%) N0 patients, 34 of 40 (85.0%) N1 patients and 25 of 51 (49.0%) N2/N3 patients. PET/CT understaged 32 patients (10.5%) and overstaged 26 patients (8.5%). One hundred and forty-three lymph nodes were proved positive for malignancy. PET/CT correctly identified 89 metastatic lymph node stations. The overall sensitivity, specificity, positive and negative predictive value and accuracy of PET/CT were 64.8%, 87.9%, 69.4%, 85.5%, and 81.0% on a per-patient basis and 62.2%, 97.9%, 69.5%, 97.1%, and 95.3%, on a per-nodal-station basis, respectively. According to nodal size, PET/CT correctly identified 67 out of 77 (87.0%) metastatic lymph node stations with a short-axis di-ameter ≥ 10 mm, and 22 out of 66 (33.3%) metastatic lymph node stations with a short-axis diameter < 10 mm (p<0.001). The incidence of false negative lymph node metastases at PET/CT was higher in patients with adenocarcinoma (42 out of 54). These data are in agreement with the published literature and confirm that integrated PET/CT is more accurate than CT in detecting nodal metastases; however, the PET/CT exam is not enough accurate to substitute mediastinoscopy.
KeywordsIntegrated PET/CTIntrathoracic Lymph Node StagingLung Cancer
Jemal, A., Siegel, R., Ward, E., Murray, T., Xu, J., Smigal, C., and Thun, M.J. (2008) Pattern and predictors of occult mediastinal lymph node involvement in non-small cell lung cancer patients with negative mediastinal uptake on positron emission tomography. European Journal of Cardio-thoracic Surgery, 56, 106-130.
Yang, P., Allen, M.S., and Aubry, M.C. (2005) Clinical features of 5,628 primary lung cancer patients: experience at Mayo clinic from 1997 to 2003. Chest, 128, 452-462.
Dwamena, B.A., Sonnad, S.S., Angobaldo, J.O., and Wahl, R.L. (1999) Metastases from non-small cell lung cancer: Mediastinal staging in the 1990s—meta-analytic compa- rison of PET and CT. Radiology, 213, 530-536.
Toloza, E.M., Harpole, L., and McCrory, D.C. (2003) Noninvasive staging of non-small cell lung cancer: a review of the current evidence. Chest, 123, 137S-146S.
Gould, M.K., Kuschner, W.G., Rydzak, C.E., Maclean, C.C., Demas, A.N., Shigemitsu, H., Chan, J.K., and Owens, D.K. (2003) Test performance of positron emission tomography and computed tomography for mediastinal staging in patients with non-small-cell lung cancer. A meta-analysis. Annals of Internal Medicine, 139, 879- 892.
Silvestri, G.A., Gould, M.K., Margolis, M.L., Tanoue, L.T., McCrory, D., Toloza, E., and Detterbeck, F., American College of Chest Physicians. (2007) Noninvasive staging of non-small cell lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest, 132, 178S-201S.
Lardinois, D., Weder, W., Hany, T.F., Kamel, E.M., Korom, S., Seifert, B., Von Schulthess, G.K., and Steinert, HC. (2003) Staging of non-small-cell lung cancer with integrated positron-emission tomography and computed tomography. New England Journal of Medicine, 348, 2500-2507.
Cerfolio, R.J., Ojha, B., Bryant, A.S., Raghuveer, V., Mountz, J.M., and Bartolucci, A.A. (2004) The accuracy of integrated PET/CT compared with dedicated PET alone for the staging of patients with non-small cell lung cancer. Annals of Thoracic Surgery, 78, 1017-1023.
Halpern, B.S., Schiepers, C., Weber, W.A., Crawford, T.L., Fueger, B.J., Phelps, M.E., and Czernin, J. (2005) Presurgical staging of non-small cell lung cancer. Positron emission tomography, integrated positron emission tomography/CT, and software image fusion. Chest, 128, 2289-2297.
Martini, N., Kris, M.G., and Ginsberg, R.J. (1997) The role of multimodality therapy in locoregional non-small cell lung cancer . Surgical Oncology Clinics of North America, 111, 1718-1723.
Cerfolio, R.J., Bryant, A.S., Ojha, B., and Eloubeidi, M. (2005) Improving the inaccuracies of clinical staging of patients with NSCLC: A prospective trial. Annals of Thoracic Surgery, 80, 1207-1214.
Shim, S.S., Lee, K.S., Kim, B-T, Chung, M.J., Lee, E.J., Han, J., Choi, J.Y., Kwon, O.J., Shim, Y.M., and Kim, S. (2005) Non-small cell lung cancer: prospective comparison of integrated FDG PET/CT and CT alone for preoperative staging. Radiology, 236, 1011-1019.
Kim, B-T, Lee, K.S., Shim, S.S., Choi, J.Y., Kwon, O.J., Kim, H., Shim, Y.M., Kim, J., and Kim, S. (2006) Stage T1 non-small cell lung cancer: preoperative mediastinal nodal staging with integrated FDG PET/CT — a pro- spective study. Radiology, 241, 501-509.
Yi, C.A., Lee, K.S., Kim, B-T, Shim, S.S., Chung, M.J., Sung, Y.M., and Jeong, S.Y. (2007) Efficacy of helical dynamic CT versus integrated PET/CT for detection of mediastinal nodal metastasis in non-small cell lung cancer. Australian Journalism Review, 188, 318-325.
Lee, B.E., Von Haag, D., Lown, T., Lau, D., Calhoun, R., and Follette, D. (2007) Advances in positron emission tomography technology have increased the need for surgical staging in non-small cell lung cancer. Journal of Thoracic and Cardiovascular Surgery, 133, 746-752.
Tournoy, K.G., Maddens, S., Gosselin, R., Van Maele, G., Van Meerbeeck, J.P., and Kelles, A. (2007) Integrated FDG-PET/CT does not make invasive staging of the intrathoracic lymph nodes in non-small cell lung cancer redundant: a prospective study. Thorax, 62, 696-701.
Hammound, Z.T., Anderson, R.C., Meyers, B.F., Guthrie, T.J., Roper, C.L., Cooper, J.D., and Patterson, G.A. (1999) The current role of mediastinoscopy in the evaluation of thoracic disease. Journal of Thoracic and Cardiovascular Surgery, 118, 894-899.
Mountain, C.F., and Dresler, C.M. (1997) Regional lymph node classification for lung cancer staging. Chest, 111, 1718-1723.
Melek, H., Gunluoglu, M.Z., Demir, A., Akin, H., Olcmen, A., and Dincer, S.I. (2008) Role of positron emission tomography in mediastinal lymphatic staging of non-small cell lung cancer. European Journal of Cartiothoracic Surgery, 33, 294-299.
Perigaud, C., Bridji, B., Roussel, J.C., Sagan, C., Mugniot, A., Duveau, D., Baron, O., and Despins, P. (2009) Prospective preoperative mediastinal lymph node staging by positron emission tomography computerized tomography in patients with non-small-cell lung cancer. European Journal of Cartiothoracic Surgery, 36,731-736.
Port, J.L. (2005) Positron emission tomographic scanning in the diagnosis and staging of non-small cell lung cancer 2 cm in size or less. Journal of Thoracic and Cardiovascular Surgery, 130, 611-615
Nomori, H., Watanabe, K., Ohtsuka, T., Naruke, T., Suemasu, K., Kobayashi, T., and Uno, K. (2004) Fluorine 18-tagged fluorodeoxyglucose positron emission tomography scanning to predict lymph node metastasis, invasiviness, or both in clinical T1 N0 M0 lung adenocarcinoma. Journal of Thoracic and Cardiovascular Surgery, 128, 396-401.
Cerfolio, R.J., Ojha, B., Briant, A.S., Brass, C.S., Bartalucci, A.A., and Mountz, J.M. (2003) The role of FDG- PET scan in staging patients with non small cell carcinoma. Annals of Thoracic Surgery, 76, 861-866
Gupta, N.C. (2001) Mediastinal lymph node sampling following positron emission tomography with fluoride- oxyglucose imagin gin lung cancer staging. Chest, 120, 521-527.
Poncelet, A.J., Lonneux, M., Coche, E., Weynand, B., and Moirhomme, Ph. (2001) FDG-PET scan enhances but does not replace surgical staging in non-small cell lung carcinoma. European Journal of Cartiothoracic Surgery, 20, 468-475.
Pieterman, R.M. (2000) Preoperative staging of non-small cell lung cancer with positron-emission tomography. New England Journal of Medicine, 343, 254-261.
Kim, B-T, Lee, K.S., Shim, S.S., Choi, J.Y., Kwon, O.J., Kim, H., Shim, Y.M., Kim, J., and Kim, S. (2006) Stage T1 non-small cell lung cancer: preoperative mediastinal nodal staging with integrated FDG PET/CT —a prospective study. Radiology, 241, 501-509.
Yi, C.A., Lee, K.S., Kim, B-T, Shim, S.S., Chung, M.J., Sung, Y.M., and Jeong, S.Y. (2007) Efficacy of helical dynamic CT versus integrated PET/CT for detection of mediastinal nodal metastasis in non-small cell lung cancer. Australian Journalism Review, 188, 318-325.
Detterbeck, F.C., Jantz, M.A., Wallace, M., Vansteenkiste, J., Silvestri, G.A. (2007) Invasive mediastinal staging of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest, 132, 202S-220S.
Smulders, S.A., Smeenk, FWJW, Janssen-Heijnen, MLG, Wielders, PLML, de Munck, DRAJ, and Postmus, P.E. (2005) Surgical mediastinal staging in daily practice. Lung Cancer, 47, 243-251.
Herth, F.J., Eberhardt, R., Vilmann, P., Krasnik, M., and Ernst, A. (2006) Real-time endobronchial ultrasound guided transbronchial needle aspiration for sampling mediastinal lymph nodes. Thorax, 61, 795-798.
Annema, J.T., Versteegh, M.I., Veseli?, M., Welker, L., Mauad, T., Sont, J.K., Willems, L.N., and Rabe, K.F. (2005) Endoscopic ultrasound added to mediastinoscopy for preoperative staging of patients with lung cancer. Journal of Clinical Investigation, 294, 931-936.
Behzadi, A., Ung, Y., Lowe, V., and Deschamps, C. (2008) The role of positron emission tomography in the management of non-small cell lung cancer. Canadian Journal of Cardiology, 3, 235-242.
Al-Sarraf, N., Aziz, R., Doddakula, K., Gately, K., Wilson, L., McGovern, E., and Young, V. (2006) Factors causing inaccurate staging of mediastinal nodal involvement in non-small cell lung cancer patients staged by positron emission tomography. Interactive CardioVascular and Thoracic Surgery.
Turkman, C., Sommezoglu, K., and Toker, A. (2007) The additional value of FDG PET imaging for distinguishing N0 or N1 from N2 stage in preoperative staging of non-small cell lung cancer in region where the prevalence of inflammatory lung disease is high. Nuclear Medicine, 32, 607-612.
De Langen, A.J., Raijmakers, P., and Riphagen, I. (2006) The size of mediastinal lymph nodes and its relation with metastatic involvement: A meta-analysis. European Jour- nal of Cartiothoracic Surgery, 29, 26-29.
Al-Sarraf, N., Aziz, R., Gately, K., Lucey, J., Wilson, L., McGovern, E., and Young, V. (2008) Pattern and predictors of occult mediastinal lymph node involvement in non-small cell lung cancer patients with negative mediastinal uptake on positron emission tomography. Euro- pean Journal of Cartiothoracic Surgery, 33,104-109.