Guest Editorial

The Status and Future of Diagnostic Infrared Imaging for Breast Cancer

Ancient physicians lacked the scientific rationale of medical practices that we take for granted in the modern era. Without any concept of the causative mechanisms, the earliest surviving medical texts describe a practical wisdom that associated body heat with the life process, excess body heat with certain diseases, and precipitously cooling after death.¹ So too was it in 1956, with the advent of the first analog infrared imagers, a physician first observed unusual “hot spots” overlying known breast cancers.² Investigators have speculated that the basis for the hot skin patterns overlying breast cancer was local inflammation or the inefficiencies of cancer’s divergent metabolism.^3,4 Amazingly invasive clinical experiments of the era revealed some features of heat flow in the breast but did not reveal the fundamental basis for the hot patterns associated with breast cancer.^5,6 A simple calculation of the energy requirements to maintain the increased temperatures commonly encountered with breast cancer effectively eliminates locally generated metabolic heat as a possible mechanism for the hot skin patterns related to breast cancer.⁷

Early thermographers started with a broad knowledge of breast cancer pathology and developed an applied empirical method from their experience with infrared imaging of many patients as part of a comprehensive diagnostic work-up and biopsy. Under the best of circumstances, the most expert of these early empirical thermographers achieved a diagnostic accuracy of 72%.⁸ While almost all breast cancers produce patterns of elevated skin temperatures, the specificity of their empirical methodology was invariably poor as it was confounded by noncancerous conditions that also present “hot spots.” It was the poor specificity demonstrated by the empirical application of thermography in the National Cancer Institute’s Breast Cancer Detection Demonstration Project that was cited as the reason breast thermography was not recommended for wide clinical application.⁹ As a result, Medicine relegated thermography and promoted X-ray mammography as the singular screening modality for breast cancer.

Fundamental limitations have constrained X-ray mammography from satisfactorily fulfilling the important role as a primary screening modality for breast cancer. Recently revised clinical guidelines that do not recommend screening X-ray mammography for women under 50 years and biennial screening of women aged 50 to 74 appear paradoxical to the persistently high incidence and serious risk of death from breast cancer outside the context of the limitations of X-ray mammography.¹⁰ The diagnostic sensitivity of X-ray mammography is significantly diminished for premenopausal women, pregnant or lactating women, women with fibrocystic/dense breasts, women with unusually large or small breasts, women with prior biopsies, women with mammoplasty or reductions, menopausal women taking HRT, and women with fast-growing carcinomas. Screening X-ray mammography demonstrates 20% false-negative rate (40% for women under 50), an 83% false-positive rate, and a 10% to 15% interval diagnosis of breast cancer in less than one year.¹¹ 2500 women require annual screening X-ray mammograms for 10 years to prevent the death of 1 woman, while 1000 of those women would have at least one false-positive finding, and 500 women would undergo unnecessary biopsy.¹² Worse, breast cancer would be overdiagnosed in 5 to 15 women, who will needlessly receive treatment with surgery, radiation, or chemotherapy singularly or in combination.¹² X-ray mammography is now controversial as a primary screening tool for breast cancer and has not demonstrated the ability to detect the different varieties of breast cancer for the at-risk population at a stage early enough to save lives.^13,14 However, most practitioners don’t get this information. Certainly, it is not part of the annual public exhortation of “breast cancer awareness” month.

Diagnostic infrared imaging has a well-established scientific basis as a biomarker for breast cancer. Two abnormal mechanisms, dysfunctional neoangiogenic blood vessels and the strong dilatory effect of nitric oxide, are responsible for the “hot spots” associated with breast cancer as the dysregulated hyperemia of core body-temperature blood flows to a relatively superficial area.^15–18 New generations of high-resolution digital instruments combined with methodology intended to differentially indicate breast cancer and the standardized reporting format of the Marseille System (TH-1–TH-5) have enabled an objective and quantitative analytic system for diagnostic infrared imaging for breast cancer with high sensitivity and specificity. These developments are a sharp departure from the empirical origins of judgment-based thermography that is characterized by the term thermology, a young but proper medical science. Applying these abilities into a clinical diagnostic tool has yielded a sensitivity of 96% and a specificity of 91% in a large-scale clinical study, a substantial improvement over that of the earlier era.¹⁹ Currently, there are well over 800 peer-reviewed clinical studies on diagnostic infrared imaging for breast cancer in the Index Medicus literature with a database in excess of 300,000 women participating in these studies, often in large cohorts and some followed up to 12 years.

With these developments, breast thermology should be progressing into medicine’s mainstream. However, diagnostic infrared imaging is an unregulated activity without effective practice guidelines. The lack of national standards has permitted a new generation of pretentious thermographers to disregard the relevant developments of the past 50 years and practice a obsolete form of judgment-based empirical thermography without the comprehensive multidisciplinary experience that enabled the early successes.^20,21

Currently, a variety of companies provide a broad range of infrared devices and reporting services, making diagnostic claims for breast cancer detection. Recently published studies based upon this underclass technology have demonstrated the vastly inferior diagnostic sensitivity to the clinical studies of 40 years ago and belie the real abilities of modern thermology.²² More appalling are the incredible claims of “whole body” diagnostic studies for “visceral health,” “digestive disorders: irritable bowel syndrome, diverticulitis and Crohn’s disease,” “immune dysfunction,” “nutritional disease (alcoholism, diabetes),” “chronic fatigue,” and “gingivitis” that are unsubstantiated by any proper studies published in peer-reviewed journals. Thermal imaging of the skin is certainly nonspecific and insensitive for pathologies in the core of the body with no demonstrated diagnostic ability to indicate inflammatory or hypermetabolic processes in the body’s core.²³ Diagnostic thermal imaging is not a legitimate tool for every medical condition, and claims for these novel applications are speculative and without diagnostic parameters at best and probably misleading. These preposterous claims can be seen as evidence of defective scholarship, doubtful veracity, and/or overriding financial interests. These unsubstantiated diagnostic claims have evoked the FDA to issue formal warning letters to some of the equipment providers.^24–26 Some companies involved with the sale of infrared imaging systems and the judgment-based thermography reporting services have created clinical thermography “professional” organizations rather than participate in established peer professional organizations. These petty organizations are simple inventions centered on proprietary interests with the purpose of justifying an obsolete methodology and covering their otherwise lack of relevant professional credential with daisy-chained and vapid “board certifications.” Considering the bold and unsubstantiated claims made by self-proclaimed thermographers sporting meaningless “certifications,” is it any wonder that many sincere medical professionals don’t know what to make of diagnostic infrared evaluation for breast cancer detection? All this considered, I call for responsible physicians and scientists involved in breast thermology to join with me in the formation of an interest group in order to advise professional organizations and regulatory agencies in matters of policy and practice.

Philip P. Hoekstra III

PO Box 2479

Birmingham, MI 48012

philiphoekstra@hotmail.com

Notes

1. Breasted JH. The Edwin Smith Papyrus. New York Historical Society; 1922.

2. Lawson R. Implications of surface temperatures in the diagnosis of breast cancer. Canad Med Assn J. 1956;75:309–310.

3. Lawson RN. Thermography – a new tool in the investigation of breast cancer. Can Serv Med J. 1957;13:517–518.

4. Head JF, Elliott RL. Thermography. Its relation to pathologic characteristics, vascularity, proliferation rate, and survival of patients with invasive ductal carcinoma of the breast. Cancer. 1997;79:186–188.

5. Lawson, op. cit.

6. Lawson RN, Chughtai MS. Breast cancer and body temperatures. Can Med Assoc J. 1963;88: 68–70.

7. Anbar M. Hyperthermia of the cancerous breast: analysis of mechanism. Cancer Lett. 1994.

8. Isard HI, Ostrum RJ, Shilo R. Thermography in breast carcinoma. Surg Gyne Obst. 1969;128:1294.

9. Baker LH. Breast Cancer Detection Demonstration Project: five year summary report. CA Cancer J Clin. 1982;32:192–225.

10. Screening for Breast Cancer: US Preventive Services Task Force Recommendation Statement. Ann Internal Med. 2009(151);10:716–726.

11. Lidbrink E, Elfving J, Frisell J, Jonsson J. Neglected aspects of false-positive findings of mammography in breast cancer screening: analysis of the false-positive cases from the Stockholm Trial. BMJ. 1996;312:273.

12. Kalagar M, Zelen M, Langmark F, et al. Effect of screening mammography on breast cancer mortality in Norway. N Engl J Med. 2010;363:1203–1210.

13. Miller AB, To T, Baines CJ, Wall C. The Canadian National Breast Screening Study-1: breast cancer mortality after 11 to 16 years of follow-up: a randomized screening trial of mammography in women age 40 to 49 years. Ann Int Med. 2002;137(5, part 1):305–312.

14. Olsen O, Gotzsche PC. Cochrane review on screening for breast cancer with mammography. Lancet. 2001(358);9290:1340–1342.

15. Loibl, S. Buck A, Strank C, et al. The role of early expression of inducible nitric oxide synthase in human breast cancer. Eur J Cancer. 2005(41);2:265–271.

16. Thornsen LL, Miles DW, Happerfield L, Bobrow LG, Knowles RG, Moncada S. Nitric oxide synthese activity in human breast cancer. Br J Cancer. 1995 July;72(1):41–44.

17. Reveneau G, Arnould L, Jolimoy G, et al. Nitric oxide synthase in human breast cancer is associated with tumor grade, proliferation rate, and expression of progesterone receptors. Lab Invest. 1999(79);10:1215–1225.

18. Martin JHJ, Begum S, Alalami O, Harrison A, Scott KWM. Endothelial nitric oxide synthase: correlation with histologic grade, lymph node status and estrogen receptor expression in human breast cancer. Tumor Biol. 2000;21:90–97.

19. Hoekstra P. The autonomic challenge and analytic breast thermology. Thermol Int. 2004(14);3:106.

20. Cockburn W. Announcement of official change in thermal reporting [online document]. Meditherm Clinic. July 26, 2005.

21. Leando P. Cold stressing breasts and why don’t we do it anymore and the thermal rating system [blog entry]. American College of Clinical Thermology. available at aact-blog.com.

22. Kontos M, Wilson R, Fentiman I. Digital infrared thermal imaging of breast lesions: sensitivity and specificity of detection of primary breast cancers. Clin Radiol. 2011 June;66(6):536–539.

23. Loviagin EV, Mus VF, Litvinov PD, Iakovleva LA. Possibilities of contact chromatic thermography in the diagnosis of lung cancer. Med Radiol (Mosk). 1991;36:11–14.

24. US Food and Drug Administration. Warning letter to Central Coast Thermography [online document]. http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2011/ucm245253.htm.

25. US Food and Drug Administration. Warning letter to Dr. Joseph Mercola. http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/2011/ucm250701.htm.

26. US Food and Drug Administration. Warning letter to Dr. Peter Leandro. [online document] http://www.fda.gov/ICECI/EnforcementActions/WarningLetters/ucm249863.htm.