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Noninvasive Clinical Staging of Primary Lung Cancer

Variant: 1   Noninvasive initial clinical staging of non–small-cell lung carcinoma.
Procedure Appropriateness Category Relative Radiation Level
MRI head without and with IV contrast Usually Appropriate O
CT chest with IV contrast Usually Appropriate ☢☢☢
CT chest without IV contrast Usually Appropriate ☢☢☢
FDG-PET/CT skull base to mid-thigh Usually Appropriate ☢☢☢☢
MRI abdomen without and with IV contrast May Be Appropriate O
MRI abdomen without IV contrast May Be Appropriate O
MRI chest without and with IV contrast May Be Appropriate O
MRI head without IV contrast May Be Appropriate O
Bone scan whole body May Be Appropriate ☢☢☢
CT abdomen and pelvis with IV contrast May Be Appropriate ☢☢☢
CT abdomen and pelvis without IV contrast May Be Appropriate ☢☢☢
CT head with IV contrast May Be Appropriate ☢☢☢
CT head without and with IV contrast May Be Appropriate ☢☢☢
CT abdomen and pelvis without and with IV contrast May Be Appropriate ☢☢☢☢
Radiography chest Usually Not Appropriate ☢
MRI chest without IV contrast Usually Not Appropriate O
CT chest without and with IV contrast Usually Not Appropriate ☢☢☢
CT head without IV contrast Usually Not Appropriate ☢☢☢

Variant: 2   Noninvasive initial clinical staging of small-cell lung carcinoma.
Procedure Appropriateness Category Relative Radiation Level
MRI head without and with IV contrast Usually Appropriate O
CT abdomen and pelvis with IV contrast Usually Appropriate ☢☢☢
CT chest with IV contrast Usually Appropriate ☢☢☢
FDG-PET/CT skull base to mid-thigh Usually Appropriate ☢☢☢☢
MRI abdomen without and with IV contrast May Be Appropriate O
MRI abdomen without IV contrast May Be Appropriate O
MRI chest without and with IV contrast May Be Appropriate O
MRI head without IV contrast May Be Appropriate O
Bone scan whole body May Be Appropriate ☢☢☢
CT abdomen and pelvis without IV contrast May Be Appropriate ☢☢☢
CT chest without IV contrast May Be Appropriate ☢☢☢
CT head with IV contrast May Be Appropriate ☢☢☢
CT head without and with IV contrast May Be Appropriate ☢☢☢
CT abdomen and pelvis without and with IV contrast May Be Appropriate ☢☢☢☢
Radiography chest Usually Not Appropriate ☢
MRI chest without IV contrast Usually Not Appropriate O
CT chest without and with IV contrast Usually Not Appropriate ☢☢☢
CT head without IV contrast Usually Not Appropriate ☢☢☢

Panel Members
Patricia M. de Groot, MDa, Jonathan H. Chung, MDb, Jeanne B. Ackman, MDc, Mark F. Berry, MDd, Brett W. Carter, MDe, Patrick M.. Colletti, f, Stephen B. Hobbs, MDg, Barbara L. McComb, MDh, Benjamin Movsas, MDi, Betty C. Tong, MD, MSj, Christopher M. Walker, MDk, Sue S. Yom, MD, PhDl, Jeffrey P. Kanne, MDm
Summary of Literature Review
Introduction/Background
Discussion of Procedures by Variant
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
A. CT Chest
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
B. FDG-PET/CT Skull Base to Mid-Thigh
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
C. CT Abdomen and Pelvis
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
D. Bone Scan Whole Body 
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
E. MRI Brain
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
F. CT Head
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
G. MRI Chest
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
H. MRI Abdomen
Variant 1: Noninvasive initial clinical staging of non–small-cell lung carcinoma.
I. Radiography Chest
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
A. CT Chest
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
B. CT Abdomen and Pelvis
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
C. FDG-PET/CT Skull Base to Mid-Thigh
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
D. MRI Brain
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
E. CT Head
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
F. Bone Scan Whole Body 
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
G. MRI Chest
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
H. MRI Abdomen
Variant 2: Noninvasive initial clinical staging of small-cell lung carcinoma.
I. Radiography Chest
Summary of Highlights
Supporting Documents

The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.

For additional information on the Appropriateness Criteria methodology and other supporting documents, please go to the ACR website at https://www.acr.org/Clinical-Resources/Clinical-Tools-and-Reference/Appropriateness-Criteria.

Appropriateness Category Names and Definitions

Appropriateness Category Name

Appropriateness Rating

Appropriateness Category Definition

Usually Appropriate

7, 8, or 9

The imaging procedure or treatment is indicated in the specified clinical scenarios at a favorable risk-benefit ratio for patients.

May Be Appropriate

4, 5, or 6

The imaging procedure or treatment may be indicated in the specified clinical scenarios as an alternative to imaging procedures or treatments with a more favorable risk-benefit ratio, or the risk-benefit ratio for patients is equivocal.

May Be Appropriate (Disagreement)

5

The individual ratings are too dispersed from the panel median. The different label provides transparency regarding the panel’s recommendation. “May be appropriate” is the rating category and a rating of 5 is assigned.

Usually Not Appropriate

1, 2, or 3

The imaging procedure or treatment is unlikely to be indicated in the specified clinical scenarios, or the risk-benefit ratio for patients is likely to be unfavorable.
Relative Radiation Level Information

Potential adverse health effects associated with radiation exposure are an important factor to consider when selecting the appropriate imaging procedure. Because there is a wide range of radiation exposures associated with different diagnostic procedures, a relative radiation level (RRL) indication has been included for each imaging examination. The RRLs are based on effective dose, which is a radiation dose quantity that is used to estimate population total radiation risk associated with an imaging procedure. Patients in the pediatric age group are at inherently higher risk from exposure, because of both organ sensitivity and longer life expectancy (relevant to the long latency that appears to accompany radiation exposure). For these reasons, the RRL dose estimate ranges for pediatric examinations are lower as compared with those specified for adults (see Table below). Additional information regarding radiation dose assessment for imaging examinations can be found in the ACR Appropriateness Criteria® Radiation Dose Assessment Introduction document.

Relative Radiation Level Designations

Relative Radiation Level*

Adult Effective Dose Estimate Range

Pediatric Effective Dose Estimate Range

O

0 mSv

 0 mSv

☢

<0.1 mSv

<0.03 mSv

☢☢

0.1-1 mSv

0.03-0.3 mSv

☢☢☢

1-10 mSv

0.3-3 mSv

☢☢☢☢

10-30 mSv

3-10 mSv

☢☢☢☢☢

30-100 mSv

10-30 mSv

*RRL assignments for some of the examinations cannot be made, because the actual patient doses in these procedures vary as a function of a number of factors (e.g., region of the body exposed to ionizing radiation, the imaging guidance that is used). The RRLs for these examinations are designated as “Varies.”
References
1. Siegel RL, Miller KD, Jemal A. Cancer statistics, 2018. CA: a Cancer Journal for Clinicians. 68(1):7-30, 2018 01.
2. Leidl R, Wacker M, Schwarzkopf L. Better understanding of the health care costs of lung cancer and the implications. Expert Rev Respir Med. 2016:1-3.
3. Rami-Porta R, Ball D, Crowley J, et al. The IASLC Lung Cancer Staging Project: proposals for the revision of the T descriptors in the forthcoming (seventh) edition of the TNM classification for lung cancer. J Thorac Oncol. 2007; 2(7):593-602.
4. Chansky K, Detterbeck FC, Nicholson AG, et al. The IASLC Lung Cancer Staging Project: External Validation of the Revision of the TNM Stage Groupings in the Eighth Edition of the TNM Classification of Lung Cancer. J Thorac Oncol. 2017;12(7):1109-1121.
5. Detterbeck FC, Boffa DJ, Kim AW, Tanoue LT. The Eighth Edition Lung Cancer Stage Classification. Chest. 2017;151(1):193-203.
6. Goldstraw P, Chansky K, Crowley J, et al. The IASLC Lung Cancer Staging Project: Proposals for Revision of the TNM Stage Groupings in the Forthcoming (Eighth) Edition of the TNM Classification for Lung Cancer. J Thorac Oncol. 2016;11(1):39-51.
7. de Langen AJ, Raijmakers P, Riphagen I, Paul MA, Hoekstra OS. The size of mediastinal lymph nodes and its relation with metastatic involvement: a meta-analysis. [Review] [22 refs]. European Journal of Cardio-Thoracic Surgery. 29(1):26-9, 2006 Jan.
8. Satoh H, Ishikawa H, Kagohashi K, Kurishima K, Sekizawa K. Axillary lymph node metastasis in lung cancer. Med Oncol. 2009;26(2):147-150.
9. Reck M, Heigener DF, Mok T, Soria JC, Rabe KF. Management of non-small-cell lung cancer: recent developments. [Review]. Lancet. 382(9893):709-19, 2013 Aug 24.
10. Travis WD, Asamura H, Bankier AA, et al. The IASLC Lung Cancer Staging Project: Proposals for Coding T Categories for Subsolid Nodules and Assessment of Tumor Size in Part-Solid Tumors in the Forthcoming Eighth Edition of the TNM Classification of Lung Cancer. [Review]. Journal of Thoracic Oncology: Official Publication of the International Association for the Study of Lung Cancer. 11(8):1204-1223, 2016 08.J Thorac Oncol. 11(8):1204-1223, 2016 08.
11. Silvestri GA, Gonzalez AV, Jantz MA, et al. Methods for staging non-small cell lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest. 143(5 Suppl):e211S-e250S, 2013 May.
12. Toloza EM, Harpole L, McCrory DC. Noninvasive staging of non-small cell lung cancer: a review of the current evidence. Chest. 2003; 123(1 Suppl):137S-146S.
13. Cerfolio RJ, Bryant AS. Distribution and likelihood of lymph node metastasis based on the lobar location of nonsmall-cell lung cancer. Ann Thorac Surg. 2006;81(6):1969-1973; discussion 1973.
14. Watanabe S, Suzuki K, Asamura H. Superior and basal segment lung cancers in the lower lobe have different lymph node metastatic pathways and prognosis. Ann Thorac Surg. 2008;85(3):1026-1031.
15. Mayo-Smith WW, Song JH, Boland GL, et al. Management of Incidental Adrenal Masses: A White Paper of the ACR Incidental Findings Committee. J. Am. Coll. Radiol.. 14(8):1038-1044, 2017 Aug.
16. MacManus MP, Hicks RJ, Matthews JP, et al. High rate of detection of unsuspected distant metastases by pet in apparent stage III non-small-cell lung cancer: implications for radical radiation therapy. Int J Radiat Oncol Biol Phys. 2001;50(2):287-293.
17. Reed CE, Harpole DH, Posther KE, et al. Results of the American College of Surgeons Oncology Group Z0050 trial: the utility of positron emission tomography in staging potentially operable non-small cell lung cancer. J Thorac Cardiovasc Surg. 2003;126(6):1943-1951.
18. Viney RC, Boyer MJ, King MT, et al. Randomized controlled trial of the role of positron emission tomography in the management of stage I and II non-small-cell lung cancer. J Clin Oncol. 2004;22(12):2357-2362.
19. van Tinteren H, Hoekstra OS, Smit EF, et al. Effectiveness of positron emission tomography in the preoperative assessment of patients with suspected non-small-cell lung cancer: the PLUS multicentre randomised trial. Lancet. 2002;359(9315):1388-1393.
20. Marom EM, McAdams HP, Erasmus JJ, et al. Staging non-small cell lung cancer with whole-body PET. Radiology. 1999;212(3):803-809.
21. Antoch G, Vogt FM, Freudenberg LS, et al. Whole-body dual-modality PET/CT and whole-body MRI for tumor staging in oncology. JAMA. 2003;290(24):3199-3206.
22. Fischer B, Lassen U, Mortensen J, et al. Preoperative staging of lung cancer with combined PET-CT. N Engl J Med. 2009;361(1):32-39.
23. Hellwig D, Groschel A, Graeter TP, et al. Diagnostic performance and prognostic impact of FDG-PET in suspected recurrence of surgically treated non-small cell lung cancer. Eur J Nucl Med Mol Imaging. 2006;33(1):13-21.
24. Birim O, Kappetein AP, Stijnen T, Bogers AJ. Meta-analysis of positron emission tomographic and computed tomographic imaging in detecting mediastinal lymph node metastases in nonsmall cell lung cancer. Ann Thorac Surg. 2005;79(1):375-382.
25. Darling GE, Maziak DE, Inculet RI, et al. Positron emission tomography-computed tomography compared with invasive mediastinal staging in non-small cell lung cancer: results of mediastinal staging in the early lung positron emission tomography trial. Journal of Thoracic Oncology: Official Publication of the International Association for the Study of Lung Cancer. 6(8):1367-72, 2011 Aug.
26. Booth K, Hanna GG, McGonigle N, et al. The mediastinal staging accuracy of 18F-Fluorodeoxyglycose positron emission tomography/computed tomography in non-small cell lung cancer with variable time intervals to surgery. Ulster Med J. 2013;82(2):75-81.
27. Gomez DR, Liao KP, Swisher SG, et al. Time to treatment as a quality metric in lung cancer: Staging studies, time to treatment, and patient survival. Radiother Oncol. 2015;115(2):257-263.
28. NCCN Clinical Practice Guidelines in Oncology. Non-Small Cell Lung Cancer. Version 3.2018.  Available at: https://www.nccn.org/professionals/physician_gls/pdf/nscl.pdf.
29. Hishida T, Yoshida J, Nishimura M, Nishiwaki Y, Nagai K. Problems in the current diagnostic standards of clinical N1 non-small cell lung cancer. Thorax. 63(6):526-31, 2008 Jun.
30. Lee PC, Port JL, Korst RJ, Liss Y, Meherally DN, Altorki NK. Risk factors for occult mediastinal metastases in clinical stage I non-small cell lung cancer. Annals of Thoracic Surgery. 84(1):177-81, 2007 Jul.
31. Boland GW, Dwamena BA, Jagtiani Sangwaiya M, et al. Characterization of adrenal masses by using FDG PET: a systematic review and meta-analysis of diagnostic test performance. [Review]. Radiology. 259(1):117-26, 2011 Apr.
32. Bury T, Barreto A, Daenen F, Barthelemy N, Ghaye B, Rigo P. Fluorine-18 deoxyglucose positron emission tomography for the detection of bone metastases in patients with non-small cell lung cancer. Eur J Nucl Med. 1998;25(9):1244-1247.
33. Cheran SK, Herndon JE 2nd, Patz EF Jr. Comparison of whole-body FDG-PET to bone scan for detection of bone metastases in patients with a new diagnosis of lung cancer. Lung Cancer. 44(3):317-25, 2004 Jun.
34. Qu X, Huang X, Yan W, Wu L, Dai K. A meta-analysis of 18FDG-PET-CT, 18FDG-PET, MRI and bone scintigraphy for diagnosis of bone metastases in patients with lung cancer. [Review]. Eur J Radiol. 81(5):1007-15, 2012 May.
35. Song JW, Oh YM, Shim TS, Kim WS, Ryu JS, Choi CM. Efficacy comparison between (18)F-FDG PET/CT and bone scintigraphy in detecting bony metastases of non-small-cell lung cancer. Lung Cancer. 65(3):333-8, 2009 Sep.
36. Kagohashi K, Satoh H, Ishikawa H, Ohtsuka M, Sekizawa K. Liver metastasis at the time of initial diagnosis of lung cancer. Med Oncol. 2003;20(1):25-28.
37. Hustinx R, Paulus P, Jacquet N, Jerusalem G, Bury T, Rigo P. Clinical evaluation of whole-body 18F-fluorodeoxyglucose positron emission tomography in the detection of liver metastases. Ann Oncol. 1998;9(4):397-401.
38. Liu T, Xu JY, Xu W, Bai YR, Yan WL, Yang HL. Fluorine-18 deoxyglucose positron emission tomography, magnetic resonance imaging and bone scintigraphy for the diagnosis of bone metastases in patients with lung cancer: which one is the best?--a meta-analysis. Clin Oncol (R Coll Radiol). 23(5):350-8, 2011 Jun.
39. Goldstraw P, Crowley J, Chansky K, et al. The IASLC Lung Cancer Staging Project: proposals for the revision of the TNM stage groupings in the forthcoming (seventh) edition of the TNM Classification of malignant tumours. J Thorac Oncol. 2007; 2(8):706-714.
40. Hochstenbag MM, Twijnstra A, Hofman P, Wouters EF, ten Velde GP. MR-imaging of the brain of neurologic asymptomatic patients with large cell or adenocarcinoma of the lung. Does it influence prognosis and treatment? Lung Cancer. 2003;42(2):189-193.
41. Earnest Ft, Ryu JH, Miller GM, et al. Suspected non-small cell lung cancer: incidence of occult brain and skeletal metastases and effectiveness of imaging for detection--pilot study. Radiology. 1999;211(1):137-145.
42. Mintz BJ, Tuhrim S, Alexander S, Yang WC, Shanzer S. Intracranial metastases in the initial staging of bronchogenic carcinoma. Chest. 1984;86(6):850-853.
43. Davis PC, Hudgins PA, Peterman SB, Hoffman JC, Jr. Diagnosis of cerebral metastases: double-dose delayed CT vs contrast-enhanced MR imaging. AJNR Am J Neuroradiol. 1991;12(2):293-300.
44. Yokoi K, Kamiya N, Matsuguma H, et al. Detection of brain metastasis in potentially operable non-small cell lung cancer: a comparison of CT and MRI. Chest. 1999;115(3):714-719.
45. Bruzzi JF, Komaki R, Walsh GL, et al. Imaging of non-small cell lung cancer of the superior sulcus: part 2: initial staging and assessment of resectability and therapeutic response. [Review] [28 refs]. Radiographics. 28(2):561-72, 2008 Mar-Apr.
46. Akata S, Kajiwara N, Park J, et al. Evaluation of chest wall invasion by lung cancer using respiratory dynamic MRI. J Med Imaging Radiat Oncol. 52(1):36-9, 2008 Feb.
47. Seo JS, Kim YJ, Choi BW, Choe KO. Usefulness of magnetic resonance imaging for evaluation of cardiovascular invasion: evaluation of sliding motion between thoracic mass and adjacent structures on cine MR images. J Magn Reson Imaging. 22(2):234-41, 2005 Aug.
48. Yang RM, Li L, Wei XH, et al. Differentiation of central lung cancer from atelectasis: comparison of diffusion-weighted MRI with PET/CT. PLoS One 2013;8:e60279.
49. Koyama H, Ohno Y, Seki S, et al. Magnetic resonance imaging for lung cancer. J Thorac Imaging. 2013;28(3):138-150.
50. Carter BW, Glisson BS, Truong MT, Erasmus JJ. Small cell lung carcinoma: staging, imaging, and treatment considerations. Radiographics. 2014;34(6):1707-1721.
51. Jett JR, Schild SE, Kesler KA, Kalemkerian GP. Treatment of small cell lung cancer: Diagnosis and management of lung cancer, 3rd ed: American College of Chest Physicians evidence-based clinical practice guidelines. Chest. 143(5 Suppl):e400S-e419S, 2013 May.
52. Kalemkerian GP, Gadgeel SM. Modern staging of small cell lung cancer. J Natl Compr Canc Netw. 2013;11(1):99-104.
53. NCCN Clinical Practice Guidelines in Oncology. Small Cell Lung Cancer. Version 2.2018.  Available at: https://www.nccn.org/professionals/physician_gls/pdf/sclc.pdf.
54. NCCN Clinical Practice Guidelines in Oncology. Small Cell Lung Cancer. NCCN Evidence Blocks™. Version 2.2018.  Available at: https://www.nccn.org/professionals/physician_gls/pdf/sclc_blocks.pdf.
55. Mirvis SE, Whitley NO, Aisner J, Moody M, Whitacre M, Whitley JE. Abdominal CT in the staging of small-cell carcinoma of the lung: incidence of metastases and effect on prognosis. AJR. 1987;148(5):845-847.
56. Arslan N, Tuncel M, Kuzhan O, et al. Evaluation of outcome prediction and disease extension by quantitative 2-deoxy-2-[18F] fluoro-D-glucose with positron emission tomography in patients with small cell lung cancer. Ann Nucl Med. 2011;25(6):406-413.
57. Azad A, Chionh F, Scott AM, et al. High impact of 18F-FDG-PET on management and prognostic stratification of newly diagnosed small cell lung cancer. Mol Imaging Biol. 2010;12(4):443-451.
58. Blum R, MacManus MP, Rischin D, Michael M, Ball D, Hicks RJ. Impact of positron emission tomography on the management of patients with small-cell lung cancer: preliminary experience. Am J Clin Oncol. 2004;27(2):164-171.
59. Bradley JD, Dehdashti F, Mintun MA, Govindan R, Trinkaus K, Siegel BA. Positron emission tomography in limited-stage small-cell lung cancer: a prospective study. J Clin Oncol. 2004;22(16):3248-3254.
60. Brink I, Schumacher T, Mix M, et al. Impact of [18F]FDG-PET on the primary staging of small-cell lung cancer. Eur J Nucl Med Mol Imaging. 2004;31(12):1614-1620.
61. Hochstenbag MM, Twijnstra A, Wilmink JT, Wouters EF, ten Velde GP. Asymptomatic brain metastases (BM) in small cell lung cancer (SCLC): MR-imaging is useful at initial diagnosis. J Neurooncol. 2000;48(3):243-248.
62. Adjei AA, Marks RS, Bonner JA. Current guidelines for the management of small cell lung cancer. Mayo Clin Proc. 1999;74(8):809-816.
63. Conen K, Hagmann R, Hess V, Zippelius A, Rothschild SI. Incidence and predictors of Bone Metastases (BM) and Skeletal-Related Events (SREs) in Small Cell Lung Cancer (SCLC): A Swiss patient cohort. J Cancer. 2016;7(14):2110-2116.
64. Johnson DH, Hainsworth JD, Greco FA. Pancoast's syndrome and small cell lung cancer. Chest. 1982;82(5):602-606.
65. American College of Radiology. ACR Appropriateness Criteria® Radiation Dose Assessment Introduction. Available at: https://edge.sitecorecloud.io/americancoldf5f-acrorgf92a-productioncb02-3650/media/ACR/Files/Clinical/Appropriateness-Criteria/ACR-Appropriateness-Criteria-Radiation-Dose-Assessment-Introduction.pdf.
Disclaimer
The ACR Committee on Appropriateness Criteria and its expert panels have developed criteria for determining appropriate imaging examinations for diagnosis and treatment of specified medical condition(s). These criteria are intended to guide radiologists, radiation oncologists and referring physicians in making decisions regarding radiologic imaging and treatment. Generally, the complexity and severity of a patient’s clinical condition should dictate the selection of appropriate imaging procedures or treatments. Only those examinations generally used for evaluation of the patient’s condition are ranked. Other imaging studies necessary to evaluate other co-existent diseases or other medical consequences of this condition are not considered in this document. The availability of equipment or personnel may influence the selection of appropriate imaging procedures or treatments. Imaging techniques classified as investigational by the FDA have not been considered in developing these criteria; however, study of new equipment and applications should be encouraged. The ultimate decision regarding the appropriateness of any specific radiologic examination or treatment must be made by the referring physician and radiologist in light of all the circumstances presented in an individual examination.