Circadian rhythm chaos: a new breast cancer marker.

Circadian rhythm chaos: a new breast cancer marker.
Keith LG, Oleszczuk JJ, Laguens M.; Department of Obstetrics and Gynecology, Northwestern University Medical School, Chicago, Illinois, USA.

The most disappointing aspect of breast cancer treatment as a public health issue has been the failure of screening to improve mortality figures. Since treatment of late stage cancer has indeed advanced, mortality can only be decreased by improving the rate of early diagnosis. From the mid-1950s to the mid-1970s, it was expected that thermography would hold the key to breast cancer detection, as surface temperature increases overlying malignant tumors had been demonstrated by thermographic
imaging. Unfortunately, detection of the 1-3 degrees C thermal differences failed to bear out its promise in early identification of cancer. In the intervening two-and-a-half decades, three new factors have emerged: it is now apparent that breast cancer has a lengthy genesis; a long-established tumor-even one of a certain minimum size-induces increased arterial/capillary vascularity in its vicinity; and thermal variations that characterize tissue metabolism are circadian ("about 24 hours") in periodicity. This paper reviews the evidence for a connection between disturbances of circadian rhythms and breast cancer. Furthermore, a scheme is proposed in which circadian rhythm "chaos" is taken as a signal of high risk for breast cancer even in the absence of mammographic evidence of neoplasm or a palpable tumor. Recent studies along this line suggest that an abnormal thermal sign, in the light of our present knowledge of breast cancer, is ten times as important an indication as is family history data.

Effectiveness of a noninvasive digital infrared thermal imaging system in the detection of breast cancer.

Effectiveness of a noninvasive digital infrared thermal imaging system in the detection of breast cancer.
Arora N, Martins D, Ruggerio D, Tousimis E, Swistel AJ, Osborne MP, Simmons RM.
Department of Surgery, New York Presbyterian Hospital-Cornell, New York, NY, USA.

BACKGROUND: Digital infrared thermal imaging (DITI) has resurfaced in this era of modernized computer technology. Its role in the detection of breast cancer is evaluated.

METHODS: In this prospective clinical trial, 92 patients for whom a breast biopsy was recommended based on prior mammogram or ultrasound underwent DITI. Three scores were generated: an overall risk score in the screening mode, a clinical score based on patient information, and a third assessment by artificial neural network.

RESULTS: Sixty
of 94 biopsies were malignant and 34 were benign. DITI identified 58 of 60 malignancies, with 97% sensitivity, 44% specificity, and 82% negative predictive value depending on the mode used. Compared to an overall risk score of 0, a score of 3 or greater was significantly more likely to be associated with malignancy (30% vs 90%, P <.03).

CONCLUSION: DITI is a valuable adjunct to mammography and ultrasound, especially in women with dense breast parenchyma.

Advances in breast imaging.

Advances in breast imaging.
 
Agnese DM. The Ohio State University, Columbus, Ohio.

Although mammography remains the most widely used tool for the early detection of breast cancers and evaluation of palpable abnormalities, a number of other imaging tools are being developed and used. Ultrasonography (US) is an excellent adjunct to conventional mammography. In addition to identifying solid and cystic abnormalities, US can often distinguish benign and malignant solid nodules. Magnetic resonance imaging (MRI) also is useful in assessing the extent of disease within the breast, particularly in women with dense breasts. MRI may be a more sensitive screening tool in women at elevated breast cancer risk. Newer techniques based on the metabolic activity of breast tumors also have been developed. One such technique is scintimammography, which uses radiolabeled tracers to detect breast malignancies. Positron emission tomography (PET), which relies on the high metabolic rate of tumors, also has been described as a method to evaluate breast disease. Other techniques, such as optical tomography and thermography, rely on angiogenesis and generated heat to identify cancers. These and other tools may help to improve both the sensitivity and specificity of cancer detection. Ideally, this improved detection results in improved outcomes in those who have breast cancer and avoidance of unnecessary procedures in those who do not.

J Biomech Eng. 2004 Apr;126(2):204-11.