CT screening

From Cancer Guidelines Wiki


Lung cancer is the leading cause of cancer death in Australia. Globally, 1.59 million deaths were due to lung cancer in 2012, by far the greatest single cause of cancer death.[1] The independent Council of Australian Governments (COAG) Reform Council highlighted lung cancer as one of six emerging areas of concern.[2] Despite overall incidence falling between 2007 and 2013, lung cancer rate among women has increased substantially, reinforcing the need for ongoing emphasis on prevention, early identification and treatment of this disease.

The advent of low dose computed tomography (LDCT) has provided an opportunity to detect lung cancers in its early stage, and the potential to reduce the overall mortality of lung cancer affected patients. This has generated much clinical and public interest in lung cancer screening. However, there is ongoing debate about the benefits and feasibility of screening and the topic remains controversial.

Only one high quality randomised control trial, NLST, demonstrated a reduction in lung cancer mortality from screening.[3]The American College of Radiology has taken the lead in setting standards in the US. Australian Government guidelines[4] call for robust governance for all screening programs, however the practicalities of this for lung cancer screening in Australia have yet to be established.

Aside from NLST, all other RCTs have been conducted in Europe and have either shown no mortality benefit or are yet to report mortality data. Only the NELSON trial is large enough to independently provide an answer on mortality. The European trials used different eligibility criteria to NLST and probably recruited slightly lower risk participants than NLST although all RCTs have included only current and former smokers.

Many expert bodies in North America, such as the U.S. Preventive Services Task Force (USPSTF)[5] and Centers for Medicare and Medicaid Services (CMS)[6], and some professional organisations in Europe, such as the ESR/ERS[7] now recommend screening. Lung cancer screening is now available in the U.S. where over 2000 U.S. radiology providers have registered with The American College of Radiology (ACR) Lung Cancer Screening Registry™ to meet quality reporting requirements and receive Medicare CT lung cancer screening payments.[8] However, opinion in the US is not uniform; the U.S. Department of Veterans Affairs elected to conduct its own pilot program and the American Academy of Family Physicians[9] concluded that the evidence was insufficient to make a recommendation. Other experts are more conservative and do not recommend screening at the present time in their country or healthcare setting.[10] In addition, some guidelines adhere firmly to NLST inclusion criteria[11][12][13][14], others based on modelling and expert opinion, have broader inclusion criteria.[5][6][7][15] The International Association for the Study of Lung Cancer (IASLC) recognizes the difficulty generalising US results to non-US health settings and recommends each country/ health care setting comes to its own independent decision[16]. There are no high level implementation studies in the Australian context supporting population-based CT screening. Furthermore there are no recent Australian cost-effectiveness data; one Australian modelled study (pre-NLST) was circumspect in its conclusions.[17] For these reasons, the Australian Department of Health Standing Committee on Screening viewpoint is that screening cannot be adopted in Australia at the present time.[18]

It is clear that worldwide expert opinion differs on a) whether or not screening should be recommended and b) which criteria should be used to determine screening eligibility. This guideline does not attempt to make general lung cancer screening recommendations; rather it attempts to make recommendations that are specific to the Australian situation at the current time. Specifically to Australia, the potential cost and cost-effectiveness of screening in this country are unknown, the generalisability of NLST results outside of the US healthcare system are uncertain and the mechanisms to ensure high quality screening practice are lacking.

Although the situation pertaining to Australia is uncertain at present, this guideline will be regularly updated as new evidence becomes available. It is likely that the situation will become clearer as time moves on, and when the NELSON results are published. In this respect we offer evidence based guidance on whether population-based screening should be offered in Australia at the current time (In people at risk of lung cancer, does population based CT screening reduce mortality?) and if it were offered, who it would potentially benefit (In people at risk of lung cancer, does population based CT screening reduce mortality?) in the context of the current international and Australia-specific uncertainties. We also highlight research gaps that need addressing in the section "Issues requiring more clinical research study to address gaps in the Australian context".

Systematic review questions

Two clinical questions in regards to CT Screening were addressed via systematic review:


  1. World Health Organisation. Cancer fact sheet. [homepage on the internet] World Health Organisation; [cited 2015 Feb 4; updated 2015 Feb]. Available from: http://www.who.int/mediacentre/factsheets/fs297/en/#.
  2. COAG Reform Council. Healthcare in Australia 2012-13: Five years of performance. Sydney: COAG Reform Council; 2014 Available from: http://apo.org.au/files/Resource/coag_healthcare-in-australia-2012-13_2014.pdf.
  3. Aberle DR, Adams AM, Berg CD, Black WC, Clapp JD, Fagerstrom RM, et al. Reduced lung-cancer mortality with low-dose computed tomographic screening. N Engl J Med 2011 Aug 4;365(5):395-409 Available from: http://www.ncbi.nlm.nih.gov/pubmed/21714641.
  4. Australian Population Health Development Principle Committee Screening Subcommittee. Population Based Screening Framework. Canberra: Commonwealth of Australia; 2008 Available from: http://www.cancerscreening.gov.au/internet/screening/publishing.nsf/Content/lung-cancer-screening.
  5. 5.0 5.1 Moyer VA, U.S. Preventive Services Task Force. Screening for lung cancer: U.S. Preventive Services Task Force recommendation statement. Ann Intern Med 2014 Mar 4;160(5):330-8 Available from: http://www.ncbi.nlm.nih.gov/pubmed/24378917.
  6. 6.0 6.1 Centers for Medicare & Medicaid Services (CMS). Decision Memo for Screening for Lung Cancer with Low Dose Computed Tomography (LDCT) (CAG-00439N). [homepage on the internet]; 2015 Dec 1 Available from: https://www.cms.gov/medicare-coverage-database/details/nca-decision-memo.aspx?NCAId=274.
  7. 7.0 7.1 Kauczor HU, Bonomo L, Gaga M, Nackaerts K, Peled N, Prokop M, et al. ESR/ERS white paper on lung cancer screening. Eur Respir J 2015 Jul;46(1):28-39 Available from: http://www.ncbi.nlm.nih.gov/pubmed/25929956.
  8. American College of Radiology (ACR). LCSR Registrants as of November 28, 2016. ACR; Available from: https://www.acr.org/~/media/ACR/Documents/PDF/QualitySafety/NRDR/Lung%20Cancer%20Screening%20Practice%20Registry/List%20of%20LCSR%20Participants.pdf.
  9. American Academy of Family Physicians (AAFP). AAFP Summary of Recommendations For Clinical Preventive Services. AAFP; 2016 Dec Available from: http://www.aafp.org/dam/AAFP/documents/patient_care/clinical_recommendations/cps-recommendations.pdf.
  10. Field JK, Baldwin D, Brain K, Devaraj A, Eisen T, Duffy SW, et al. CT screening for lung cancer in the UK: position statement by UKLS investigators following the NLST report. Thorax 2011 Aug;66(8):736-7 Available from: http://www.ncbi.nlm.nih.gov/pubmed/21724746.
  11. Bach PB, Mirkin JN, Oliver TK, Azzoli CG, Berry DA, Brawley OW, et al. Benefits and harms of CT screening for lung cancer: a systematic review. JAMA 2012 Jun 13;307(22):2418-29 Available from: http://www.ncbi.nlm.nih.gov/pubmed/22610500.
  12. Frauenfelder T, Puhan MA, Lazor R, von Garnier C, Bremerich J, Niemann T, et al. Early detection of lung cancer: a statement from an expert panel of the Swiss university hospitals on lung cancer screening. Respiration 2014;87(3):254-64 Available from: http://www.ncbi.nlm.nih.gov/pubmed/24458197.
  13. Couraud S, Cortot AB, Greillier L, Gounant V, Mennecier B, Girard N, et al. From randomized trials to the clinic: is it time to implement individual lung-cancer screening in clinical practice? A multidisciplinary statement from French experts on behalf of the French intergroup (IFCT) and the groupe d'Oncologie de langue francaise (GOLF). Ann Oncol 2013 Mar;24(3):586-97 Available from: http://www.ncbi.nlm.nih.gov/pubmed/23136229.
  14. Roberts H, Walker-Dilks C, Sivjee K, Ung Y, Yasufuku K, Hey A, et al. Screening high-risk populations for lung cancer. Toronto (ON): Cancer Care Ontario; 2013 Available from: https://www.cancercare.on.ca/common/pages/UserFile.aspx?fileId=287881.
  15. NCCN. National Comprehensive Cancer Network Guidelines. Version 2. Fort Washington, PA, USA: National Comprehensive Cancer Network (NCCN); 2016.
  16. Field JK, Aberle DR, Altorki N, Baldwin DR, Dresler C, Duffy SW, et al. The International Association Study Lung Cancer (IASLC) Strategic Screening Advisory Committee (SSAC) response to the USPSTF recommendations. J Thorac Oncol 2014 Feb;9(2):141-3 Available from: http://www.ncbi.nlm.nih.gov/pubmed/24419409.
  17. Manser R, Dalton A, Carter R, Byrnes G, Elwood M, Campbell DA. Cost-effectiveness analysis of screening for lung cancer with low dose spiral CT (computed tomography) in the Australian setting. Lung Cancer 2005 May;48(2):171-85 Available from: http://www.ncbi.nlm.nih.gov/pubmed/15829317.
  18. Department of Health Standing Committee on Screening.. Position Statement: Lung Cancer Screening using Low-Dose Computed Tomography. Canberra: Commonwealth of Australia; 2015 Available from: http://www.cancerscreening.gov.au/internet/screening/publishing.nsf/Content/lung-cancer-screening.