Breast Cancer Re-evaluation Methods (Ireland)

A 1999 study found no decrease in breast-cancer mortality in Sweden, where screening has been recommended since 1985. The study reviewed the methodological quality of the mammography trials and an influential Swedish meta-analysis.[843]

The data show that for every 1000 women screened biennially throughout 12 years, one breast-cancer death is avoided whereas the total number of deaths is increased by six. (Lancet 2000; 355: 129-34)

The very low energy X-rays used in screening mammography (26–30 kVp) are expected to be more hazardous, per unit dose, than high-energy X- or c-rays, such as those to which A-bomb survivors (from which radiation risk estimates are derived) were exposed.[4389]

If the risks per unit dose of mammographic X-rays are indeed about twice as large as those from the radiations at Iroshima and Nagasaki, this would be of significance in assessing the benefit–risk balance for screening mammography.[6379]

There is evidence that low-energy X-rays as used in mammographic screening produce an increased biological risk per unit dose relative to higher-energy photons.[6378]

Considerable controversy currently exists regarding the biological effectiveness of 29 kVp X rays which are used for

mammography screening.[7890]

The high-energy X-ray spectrum had been used to matches that experienced by survivors 1500 m from the epicenter of the Nagasaki atomic bomb.[7890]

This result suggests a need to re-evaluate the risks associated with mammography breast screening. On the basis of the best estimate for RBEm (Relative Biological Effectiveness), the 95% confidence intervals for the increased risks for mammography are 2.7 to 5.3 times that previously assumed.[7891]

Because the risk-benefit in detecting breast cancer with mammograms and the increasing number of this disease every year in Ireland, it is essential for the Irish society to re-evaluate this method and integrate other methods for early detection of breast cancer.[ICIM 05]

With the current emphasis on earlier detection, there is now renewed interest in the parallel development of complimentary imaging techniques that can also exploit the precocious metabolic, immunological and vascular changes associated with early tumor growth.[7893]

While promising, techniques such as scintimammography[930], doppler ultrasound[998], and MRI[1353], are associated with a number of disadvantages that include exam duration, limited accessibility, need of intravenous access, patient discomfort, restricted imaging area, difficult interpretation and limited availability of the technology. Like ultrasound, they are more suited to use as second-line options to pursue the already abnormal clinical or mammographic evaluation.[7893]

Thus, noninvasive methods are needed to aid clinicians in distinguishing benign from malignant breast tissue. Imaging techniques used in conjunction with mammography and physical examination often include sonography, CT, and MR imaging.[6832]

Although promising, CT and MR imaging are generally considered too costly for routine use. In addition, MR imaging has not proven to be efficacious in young patients, because MR findings may lead to an unacceptably high number of workups for benign lesions while detecting few malignancies.[4218]

Sestamibi scintimammography has also been used with varying success to evaluate breast lesions scheduled for biopsy: sensitivities have ranged from 55% to 98%, and specificities have ranged from 79% to 95%.[3190],[3914] Disadvantages of this technique include the expense, duration of the examination, and patient exposure to ionizing radiation.

Sonography is more cost-effective than either CT or MR imaging but has limitations[6170],[5932]. Like mammography, sonography relies on the expertise of the technician and the interpretative skills of the radiologist.

One promising modality for aiding clinicians in differentiating malignant from benign breast lesions is Medical Infrared Imaging. This modality is noninvasive and detects physiologic tissue response, rather than evaluating anatomic features. As heat is released from the body, a portion is in the form of infrared radiation.[6832]

Several physiologic features related to malignant tissue may contribute to the infrared signal, including increased blood flow in the area surrounding a malignancy, angiogenesis, and the release of vasoactive mediators[8134],[5992]. The infrared imaging system uses a camera that is highly sensitive to infrared radiation in the appropriate spectrum. This computerized system is designed to show that benign tissue can be differentiated from neoplastic tissue on the basis of the relatively higher strength of the infrared signal in malignant tissue[6832].

All objects with a temperature above absolute zero (-273 K) emit infrared radiation from their surface. The Stefan-Boltzmann Law defines the relation between radiated energy and temperature by stating that the total radiation emitted by an object is directly proportional to the object’s area and emissivity and the fourth power of its absolute temperature.[7893]

Since the emissivity of human skin is extremely high (within 1% of that of a black body), measurements of infrared radiation emitted by the skin can be converted directly into accurate temperature values.

Infrared rays are found in the electromagnetic spectrum within the wavelengths of 0.75 micron - 1mm. Human skin emits infrared radiation mainly in the 2 - 20 micron wavelength range, with an average peak at 9-10 microns.[789]

At ICIM a state-of-the-art infrared radiation detection system utilize ultra-sensitive infrared cameras and sophisticated computers to detect, analyze, and produce high-resolution diagnostic images of these infrared emissions. The problems encountered with first generation infrared camera systems such as improper detector sensitivity (low-band), thermal drift, calibration, analog interface, etc. have been solved for almost two decades.[ICIM 05]

Lawson and Chughtai, two McGill University surgeons, published an elegant intra-operative study demonstrating that the increase in regional skin surface temperature associated with breast cancer was related to venous convection.[7731] This early quantitative experiment added credence to previous research suggesting that infrared findings were related to both increased vascular flow and increased metabolism.

Infrared imaging of the breast may have critical prognostic significance since it may correlate with a variety of pathologic prognostic features such as tumor size, tumor grade, lymph node status and markers of tumor growth.[6113] The pathologic basis for these infrared findings, however, is uncertain. One possibility is increased blood flow due to vascular proliferation (assessed by quantifying the microvascular density (MVD)) as a result of tumor associated angiogenesis.

Although in one study[3942], the MVD did not correlate with abnormal infrared findings. However, the imaging method used in that study consisted of contact plate technology (liquid crystal thermography (LCT)), which is not capable of modern computerized infrared analysis. Consequently, LCT does not possess the discrimination and digital processing necessary to begin to correlate histological and discrete vascular changes.[2391]

The concept of angiogenesis, as an integral part of early breast cancer, was emphasized in 1996 by Guido and Schnitt. Their observations suggested that it is an early event in the development of breast cancer and may occur before tumor cells acquire the ability to invade the surrounding stroma and even before there is morphologic evidence of an in-situ carcinoma.[1383]

Anti-angiogenesis therapy is now one of the most promising therapeutic strategies and has been found to be pivotal in the new paradigm for consideration of breast cancer development and treatment.[5493] In 1996, in his highly reviewed textbook entitled Atlas of Mammography - New Early Signs in Breast Cancer, Gamagami studied angiogenesis by infrared imaging and reported that hypervascularity and hyperthermia could be shown in 86% of non-palpable breast cancers. He also noted that in 15% of these cases infrared imaging helped to detect cancers that were not visible on mammography.[6631]

The underlying principle by which thermography (infrared imaging) detects pre-cancerous growths and cancerous tumors surrounds the well documented recruitment of existing vascularity and neoangiogenesis which is necessary to maintain the increased metabolism of cellular growth and multiplication. The biomedical engineering evidence of thermography’s value, both in model in-vitro and clinically in-vivo studies of various tissue growths, normal and neoplastic, has been established.[7812],[6943]

In a mobile unit examination of rural Wisconsin, Hobbins screened 37,506 women using thermography. He reported the detection of 5.7 cancers per 1,000 women screened with a 12% false-negative and 14% false-positive rate. His findings also corroborated with others that thermography is the sole early initial signal in 10% of breast cancers.[3911],[2776]

Spitalier and associates screened 61,000 women using thermography over a 10 year period. The false-negative and positive rate was found to be 11% (89% sensitivity and specificity). 91% of the nonpalpable cancers (T0 rating) were detected by thermography. Of all the patients with cancer, thermography alone was the first alarm in 60% of the cases. The authors also noted that “in patients having no clinical or radiographic suspicion of malignancy, a persistently abnormal breast thermogram represents the highest known risk factor for the future development of breast cancer”.[7927]

In a unique study comprising 39,802 women screened over a 3 year period, Haberman and associates used thermography and physical examination to determine if mammography was recommended. They reported an 85% sensitivity and 70% specificity for thermography. Haberman cautioned that the findings of thermographic specificity could not be extrapolated from this study as it was well documented that long term observation (8-10 years or more) is necessary to determine a true false-positive rate. The authors noted that 30% of the cancers found would not have been detected if it were not for thermography.[3798]

Gros and Gautherie reported on 85,000 patients screened with a resultant 90% sensitivity and 88% specificity. In order to investigate a method of increasing the sensitivity of the test, 10,834 patients were examined with the addition of a cold-challenge (two types: fan and ice water) in order to elicit an autonomic response. This form of dynamic thermography decreased the false-positive rate to 3.5% (96.5% sensitivity).[6173],[7014]

In a series of 4,000 confirmed breast cancers, Thomassin and associates observed 130 sub-clinical carcinomas ranging in diameter of 3-5 mm. Both mammography and thermography were used alone and in combination. Of the 130 cancers, 10% were detected by mammography only, 50% by thermography alone, and 40% by both techniques. Thus, there was a thermal alarm in 90% of the patients and the only sign in 50% of the cases.[2932]

In a study by Gautherie and associates, the effectiveness of thermography in terms of survival benefit was discussed. The authors analyzed the survival rates of 106 patients in whom the diagnosis of breast cancer was established as a result of the follow-up of thermographic abnormalities found on the initial examination when the breasts were apparently healthy (negative physical and mammographic findings). The control group consisted of 372 breast cancer patients. The patients in both groups were subjected to identical treatment and followed for 5 years. A 61% increase in survival was noted in the patients who were followed-up due to initial thermographic abnormalities.

The authors summarized the study by stating that “the findings clearly establish that the early identification of women at high risk of breast cancer based on the objective thermal assessment of breast health results in a dramatic survival benefit”.[4419],[5820]

As early as 1976, at the Third International Symposium on Detection and Prevention of Cancer in New York, thermography was established by consensus as the highest risk marker for the possibility of the presence of an undetected breast cancer. It had also been shown to predict such a subsequent occurrence. The Wisconsin Breast Cancer Detection Foundation presented a summary of its findings in this area, which has remained undisputed. This, combined with other reports, has confirmed that thermography is the highest risk indicator for the future development of breast cancer and is 10 times as significant as a first order family history of the disease.[2342]

In a study of 10,000 women screened, Gautherie found that, when applied to asymptomatic women, thermography was very useful in assessing the risk of cancer by dividing patients into low- and high-risk categories. This was based on an objective evaluation of each patient’s thermograms using an improved reading protocol that incorporated 20 thermopathological factors.[6778]

From a patient base of 58,000 women screened with thermography, Gros and associates followed 1,527 patients with initially healthy breasts and abnormal thermograms for 12 years. Of this group, 40% developed malignancies within 5 years. The study concluded that “an abnormal thermogram is the single most important marker of high risk for the future development of breast cancer”.[7129]

Spitalier and associates followed 1,416 patients with isolated abnormal breast thermograms. It was found that a persistently abnormal thermogram, as an isolated phenomenon, is associated with an actuarial breast cancer risk of 26% at 5 years. Within this study, 165 patients with non-palpable cancers were observed. In 53% of these patients, thermography was the only test which was positive at the time of initial evaluation. It was concluded that: (1) A persistently abnormal thermogram, even in the absence of any other sign of malignancy, is associated with a high risk of developing cancer, (2) This isolated abnormal also carries with it a high risk of developing interval cancer, and as such the patient should be examined more frequently than the customary 12 months, (3) Most patients diagnosed as having minimal breast cancer have abnormal thermograms as the first warning sign.[6553],7329]

Because of thermography’s unique ability to image the thermovascular aspects of the breast, extremely early warning signals (from 8-10 years before any other detection method) have been observed in long-term studies. Consequently, thermography is the earliest known indicator for the future development of breast cancer. It is for this reason that an abnormal infrared image is the single most important marker of high risk for developing breast cancer.[7893]

Thus, thermography has a significant place as one of the major front-line methods of breast cancer detection.

The large patient populations and long survey periods in many of the above clinical studies yields a high significance to the various statistical data obtained. This is especially true for the contribution of thermography to early cancer diagnosis, as an invaluable marker of high-risk populations, and therapeutic decision making (a contribution that has been established and justified by the unequivocal relationship between heat production and tumor doubling time).[7893]

The high-resolution digital infrared imaging (Thermography) technology used at ICIM benefits greatly from enhanced image production, standardized image interpretation protocols, computerized comparison and storage, and sophisticated image enhancement and analysis.[7893],[ICIM 05]

Over 30 years of research and 800 peer-reviewed studies encompassing well over 300,000 women participants has demonstrated thermography’s abilities in the early detection of breast cancer. Ongoing research into the thermal characteristics of breast pathologies will continue to investigate the relationships between neoangiogenesis, chemical mediators, and the neoplastic process.[7893]

It is unfortunate, but many physicians still hesitate to consider thermography as a useful tool in clinical practice in spite of the considerable research database, continued improvements in both thermographic technology and image analysis, and continued efforts on the part of the thermographic societies. This attitude may be due to the fact that the physical and biological bases of thermography are not familiar to most physicians.[7893]

The other methods of cancer investigations refer directly to topics of medical teaching. For instance, radiography and ultrasonography refer to anatomy. Thermography, however, is based on thermodynamics and thermokinetics, which are unfamiliar to most physicians, though man is experiencing heat production and exchange in every situation he undergoes or creates.[7893]

Considering the contribution that thermography has demonstrated thus far in the field of early cancer detection, all possibilities should be considered for promoting further technical, biological, and clinical research in this procedure.

The efficacy of Computerized Infrared Imaging Analysis to evaluate Mammographically suspicious lesions is a well documented fact.[7893]

Infrared imaging offers a safe noninvasive procedure that would be valuable as an adjunct to mammography in determining whether a lesion is benign or malignant.[6832]

Mammography, reveals occult malignant lesions in asymptomatic women at an earlier stage and in smaller lesions, generally producing a more favorable prognosis than is possible by self-examination. Despite the value of mammography in revealing breast malignancies, most radiographically identified lesions are ultimately found to be benign on histologic assessment after biopsy.[6832]

Mammography is the well-established standard method for identifying suspicious lesions on the basis of anatomic information. However, as radiologists assess the various ways to improve detection of breast cancer and to better distinguish between benign and malignant suspicious lesions, increasing interest is being focused on the physiologic profile of the disease. [6832]

Other diagnostic modalities for breast cancer that rely, at least in part, on physiologic processes include sestamibi scintimammography, Doppler sonography, gadolinium- enhanced MR imaging, and positron emission tomography.[6832]

The computerized infrared imaging system that we used was developed to assist physicians in differentiating benign tissue from malignant tissue by characterizing different patterns in the infrared signal emitted by the breast. The infrared imaging system could be used as an adjunct for further evaluating a mammographically apparent breast abnormality when the radiologist has a low-to-moderate suspicion that a malignancy is present.[ICIM 05],[6832]

Undergoing breast biopsy of benign tissues places substantial physical and psychologic burdens on the patient without improving patient care. In addition, such testing has a great economic impact on the health care system.[7313],[7893] Infrared imaging assessment offers a noninvasive, safe procedure that could be helpful in determining whether an immediate biopsy is warranted.[6832]

Infrared imaging is a safe modality that provides physiologic data about a lesion. The physiologic view provided by infrared imaging complements the anatomic view provided by mammography with a very high sensitivity and negative predictive value in masses. Thus, this dynamic computerized infrared imaging system could be a valuable addition to the physicians’ armamentarium of diagnostic tools.[6832]

The Irish Centre of Integrated Medicine (ICIM) objective is to integrate the best and most scientifically methods to decrease breast cancer mortality. This objective will be achieved by social education and national breast screenings programs. Medical Infrared Thermography is used at ICIM in conjunction with scientific data and research to help evaluate breast pathologies and other medical conditions.

Because hundreds of abstracts were used directly and indirectly for this re-evaluation, physical and economical viability in attaching to this report is not justified. More than 8.000 publications on this subject from 1989 to 2004 are available at ICIM’s data research.

For more information on this topic please call ICIM Medics on +353 45 844 819 or email us at info@icim.ie

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