Year : 2008 | Volume
: 3 | Issue : 6 | Page : 79--81
Radiologic workup of lung cancer
Sara Al Ghanem
King Abdulaziz Medical City for National Guard, Riyadh, Saudi Arabia
Sara Al Ghanem
Department of Medical Imaging (Mail code 1222), P.O. Box 22490, Riyadh 11426
Imaging plays an important role in the management of lung cancer. Imaging studies are used for diagnosis and to determine the stage of the disease as well as to assess tumor response and, thus, guide further treatment of patients. This manuscript will review the use of imaging studies in the management of lung cancer.
|How to cite this article:|
Al Ghanem S. Radiologic workup of lung cancer.Ann Thorac Med 2008;3:79-81
|How to cite this URL:|
Al Ghanem S. Radiologic workup of lung cancer. Ann Thorac Med [serial online] 2008 [cited 2021 Jun 19 ];3:79-81
Available from: https://www.thoracicmedicine.org/text.asp?2008/3/6/79/43109
Non-Small-Cell Carcinoma (NSCLC)
The treatment and prognosis of patients with NSCLC depend on the disease staging (i.e., the determination of the anatomic extent of disease at initial presentation). , Uniform criteria for reporting the findings of clinical and / or pathologic evaluation are important for the initial management of patients with NSCLC. Radiologic imaging is directed at detecting nonresectable disease (T4 or N3 or M1). ,,
The American Society of Clinical Oncology (ASCO) has published evidence-based guidelines for the diagnostic evaluation of patients with NSCLC.  In the staging of locoregional disease, these guidelines recommend that a chest radiograph and contrast-enhanced chest CT, which should include the liver and the adrenal glands, should be performed. In addition, the ASCO recommendations state that a whole-body FDG-PET should be performed when there is no evidence of distant metastasis on CT scan.  This recommendation is based on the fact that FDG-PET imaging improves the detection of nodal and distant metastases and frequently alters patient management. ,
FDG-PET plays a substantial role in identifying patients as surgical candidates who, otherwise, might be considered to have unresectable tumors. Treatment can be altered in up to 41% of cases on the basis of the FDG-PET findings. , The high sensitivity and high negative predictive value of FDG-PET in most malignant tumors enables this technique to play an even a greater role in tumor management at initial staging and follow-up. Staging with CT and MRI has been reported to have a sensitivity of 50-60%, while mediastinoscopy has a sensitivity of 87% and a specificity of 91%. In comparison, a recent comprehensive study reported that PET scan has a sensitivity of 93% and a specificity of 99%. 
Owing to its high negative predictive value (about 94%), FDG-PET, combined with chest CT preoperatively, may alleviate the need for surgical staging in FDG-PET-negative cases. However, when there is a positive FDG-PET result, further diagnostic procedures should be done to avoid overstaging.  Integrated PET-CT scanners can also determine the precise anatomic location of focal increased uptake, increasing accuracy of staging. ,,
The use of magnetic resonance imaging (MRI)
MRI can usefully complement CT scan; its major advantage over CT is the high-density resolution that it can provide. It is mainly used to assess involvement of major blood vessels, trachea, carina, or chest wall, and to look for cardiac and diaphragmatic invasion. Furthermore, MRI is superior to CT scan in the evaluation of superior sulcus tumors. ,,
Endoscopic ultrasound (US)
Endobronchial US permits identification and localization of mediastinal lymph nodes during flexible bronchoscopy and permits more reliable needle aspiration of small lymph nodes.  It is highly sensitive. A sensitivity of 92% and a specificity of 100%, comparable to that of surgical staging, was reported in paratracheal, subcarinal, and hilar lymphadenopathy. ,
Transesophageal endoscopic US is also highly accurate in mediastinal staging. It is highly sensitive in the detection of metastatic disease in lymph nodes, particularly in the subcarinal, inferior mediastinal, and aortopulmonary regions. 
Evaluation of pleural effusion
The majority of pleural effusions are due to involvement of the pleura by tumor (T4), however, effusions could be parapneumonic or sympathetic, in which case the presence of the effusion does not upstage tumor nor preclude resection. Cytologic examination will detect approximately 65% of malignant effusions. If the first thoracentesis is negative, a second one should be performed. If the second thoracentesis is also negative, thoracoscopy to look for pleural metastasis is recommended. ,,, Aspiration of the pleural effusion under imaging guidance may be needed, especially in cases of small or loculated effusions.
Radiology workup for NSCLC
All patients should have a contrast-enhanced CT scan of the chest and upper abdomen including adrenal glands and liver.
Stage I (A and B): PET scan, if availableStage II A: PET scan, if available. Brain MRI for nonsquamous histologyStage II B: PET scan, if available MRI brain MRI spine and thoracic inlet for superior sulcus tumor abutting the spine or the suclavian vesselsStage III A: PET scan; if not available, bone scan. MRI brain MRI spine and thoracic inlet for superior sulcus tumors abutting the spine or the suclavian vesselsStage III B: PET scan; if not available, bone scan. Brain MRI Thoracentesis or pericardiocentesis. If two thoracentesis attempts are negative, perform thoracoscopyStage IV with solitary metastasis: PET scan; if not available, bone scan. Brain MRIStage IV with disseminated metastasis: Workup as clinically indicated
Follow-up should include CT scan of the chest every 4-6 months for 2 years; after this period, CT scan of the chest should be done annually.
Small-Cell Lung Carcinoma (SCLC)
Most patients with SCLC have extensive disease at the time of diagnosis. SCLC is staged into: 1) limited disease, where the primary tumor and nodal involvement are limited to one hemithorax and 2) extensive stage, when disease has spread beyond the limits defined for limited disease.
There is no consensus regarding the imaging and invasive procedures that should be performed for staging and evaluation of patients with SCLC. MRI has been advocated because of its ability to assess the liver, adrenals, brain, and axial skeleton in a single study. PET-FDG may improve the accuracy of staging of patients with SCLC. However, experience with PET in SCLC is still limited and it is not used in routine staging.
Routine brain MRI is recommended even if there is no evidence of metastasis at presentation, because CNS metastases are common and can be asymptomatic. ,, Obtaining CT or MRI of the abdomen is also recommended as a routine procedure in the staging of SCLC, because metastasis to the liver (30%) and retroperitoneal lymph nodes (11%) are common and often asymptomatic and liver function tests could be normal.  Bone scan is routinely performed for the same reason. Additionally, bone marrow aspiration can be performed if clinically indicated.
Radiology workup in SCLC
CT scan of chest and abdomenMRI of the brainBone scanPET scan is optional and not routinely recommendedThoracentesis is recommended if there is pleural effusion and can be followed by thoracoscopy if the tap is negative.
CT of the chest, adrenal glands, and liver should be done to check response to treatment; brain CT or MRI is recommended if brain radiation has been given. The imaging studies of the chest and upper abdomen should be repeated every 4-6 months in the first 2 years. A new nodule, appearing after 2 years, is to be considered as a new neoplasm and worked up accordingly.
In summary, imaging studies are very important in the management of patients with lung cancer and should be used as recommended so that patients get the best possible care.
|1||Mountain CF. Revisions in the international system for staging lung cancer. Chest 1997;111:1710-7.|
|2||Postmus PE, Brambilla E, Chansky K, Crowley J, Goldstraw P, Patz EF Jr, et al. The IASLC Lung Cancer Staging Project: proposals for revision of the M descriptors in the forthcoming (seventh) edition of the TNM classification of lung cancer. J Thorac Oncol 2007;2:686-93. |
|3||Erasmus JJ, Sabloff BS. CT, PET, and MRI in staging lung cancer. Clin Chest Med 2008;29:39-57.|
|4||Pfister DG, Johnson DH, Azzoli CG, Sause W, Smith TJ, Baker S Jr, et al. American Society of Clinical Oncology treatment of unresectable non- small-cell lung cancer guideline; update 2003. J Clin Oncol 2004;22:330-53.|
|5||van Tinteren H, Hoekstra OS, Smit EF, van den Bergh JH, Schreurs AJ, Stallaert RA, et al. Effectiveness of PET in the preoperative assessment of patients with suspected non-small cell lung cancer: The PLUS multicentre randomized trial. Lancet 2002;359:1388-93.|
|6||Pieterman RM, van Putten JW, Meuzelaar JJ, Mooyaart EL, Vaalburg W, Ko'λter GH, et al. Preoperative staging of non-small-lung cancer with positron-emission tomography. N Engl J Med 2000;343:254-61. |
|7||Kostakoglu L, Agress H, Goldsmith SJ. Clinical role of FDG-PET in evaluation of cancer patients. Radiographics 2003;23:315-40.|
|8||Keidar Z, Haim N, Guralnik L, Wollner M, Bar-Shalom R, Ben-Nun A, et al. PET-CT using F18-FDG in suspected lung cancer recurrence: Diagnostic value and impact on patient management. J Nucl Med 2004;45:1640-6.|
|9||Shim SS, Lee KS, Kim BT, Chung MJ, Lee EJ, Han J, et al. Non-small cell lung cancer: Prospective comparison of integrated FDG-PET-CT and CT alone for preoperative staging. Radiology 2005;236:1011-9.|
|10||Lardinois D, Weder W, Hany TF, Kamel EM, Korom S, Seifert B, et al. Staging of non-small-cell lung cancer with integrated PET and CT. N Engl J Med 2003;348:2500-7. |
|11||Antoch G, Stattaus J, Nemat AT, Marnitz S, Beyer T, Kuehl H, et al. Non-small cell lung cancer: Dual-modality PET-CT in preoperative staging. Radiology 2003;229:526-33.|
|12||Hatabu H, Stock KW, Sher S, Edinburgh KJ, Levin DL, Garpestad E, et al. Magnetic resonance imaging of the thorax: Past, present and future. Radiol Clin North Am 2000;38:593-620.|
|13||Webb WR, Gatsonics C, Zerhouni EA, Heelan RT, Glazer GM, Francis IR, et al. CT and MR imaging in staging non-small cell bronchogenic carcinoma: Report of the Radiologic Diagnostic Oncology Group. Radiology 1991;178:705-13.|
|14||Webb WR, Sostman HD. MR imaging of thoracic disease: Clinical uses. Radiology 1992;182:621-30.|
|15||Bruzzi JF, Komaki R, Walsh GL, Truong MT, Gladish GW, Munden RF, et al. Imaging of non-small cell lung cancer of the superior sulcus: Part 2: Initial staging and assessment of respectability and therapeutic response. Radiographics 2008;28:561-72.|
|16||Silvestri GA, Hoffman BJ, Bhutani MS. Endoscopic ultrasound with fine-needle aspiration in the diagnosis and staging of lung cancer. Ann Thorac Surg 1996;61:1441-5. |
|17||Yasufuku K, Nakajima T, Motoori K, Sekine Y, Shibuya K, Hiroshima K, et al. Comparison of endobronchial US, positron emission tomography, and CT for lymph node staging of lung cancer. Chest 2006;130:710.|
|18||Larsen SS, Vilmann P, Kransil M, Dirksen A, Clementsen P, Skov BG, et al. Endoscopic US guided biopsy versus mediastinoscopy for analysis of paratracheal and subcarinal lymph nodes in lung cancer staging. Lung Cancer 2005;48:85-92.|
|19||Schenk DA, Chambers SL, Derdak S, Komadina KH, Pickard JS, Strollo PJ, et al. Comparison of the Wang 19-gauge and 22 gauge needles in mediastinal staging of lung cancer. Am Rev Respir Dis 1993;147:1251-8.|
|20||Katis K, Inglesos E, Zachariadis E, Palamidas P, Paraskevopoulos I, Sideris G, et al. The role of transbronchial needle aspiration in the diagnosis of peripheral lung masses or nodules. Eur Respir J 1995;8:963-6.|
|21||Davenport RD. Rapid on-site evaluation of transbronchial aspirates. Chest 1990;98:58-61.|
|22||Niho S, Fujii H, Murakami K. Detection of unsuspected metastasis and-or regional lymph nodes by FDG-PET in LD-SCLC scan in apparent limited-disease small- cell cancer. Lung Cancer 2007;5:328-33. |
|23||Darling GE. Staging of the patient with small cell lung cancer. Chest Surg Clin N Am 1997;7-81-94. |
|24||Elias AD. Small cell lung cancer: State-of-the-art therapy in 1996. Chest 1997;112:251. |
|25||van de Pol M, van Oosterhout AG, Wilmink JT, ten Velde GP, Twijnstra A. MRI in detection of brain metastases at initial staging of small-cell lung cancer. Neuroradiology 1996;38:207-10. |
|26||Abrams J, Doyle LA, Aisner J. Staging prognostic factors, and special consideration in small cell lung cancer. Semin Oncol 1988;15:261-77.|