Correlation of dynamic infrared imaging with radiologic and pathologic response for patients treated with primary systemic therapy for locally advanced breast cancer

Abstract

10696 Background: Assessment of response to therapy for locally advanced breast cancer includes serial assessments of physical exam, radiologic imaging, or repeated biopsies. Expense, subjective assessment, and patient risk make these methods impractical. Dynamic infrared imaging (DIRI) utilizes a quantum well infrared photon (QWIP) sensor with software to analyze the emission patterns over time. DIRI can detect biological temperature gradients with sensitivity of 0.009ºC. Tumor-induced local tissue nitric oxide production can increase local capillary blood flow. Anti-tumor therapies have been shown to result in decreased peri-tumoral capillary blood flow. These changes in temperature, detected by serial DIRI imaging, may provide a low cost, non-invasive, easily reproducible objective tool for real-time clinical assessment. Methods: In this prospective pilot study, we are evaluating patients with locally advanced breast cancer using serial DIRI. Primary endpoints include: sensitivity, specificity, PPV, and NPV of DIRI in comparison to pathologic response, concordance of DIRI to physical exam, and concordance of DIRI to standard radiographic evaluation at initial diagnosis and prior to surgery. DIRI results are reported as quantification of changes in the 0.2Hz modulation of temperature over the breast during the course of treatment and measurement of area of average temperature in a region of interest compared between breasts. One hundred patients will be enrolled in this trial. Results: Sixteen patients have been enrolled. Six have proceeded to surgery. All but one patient exhibited evidence of tumor response by physical exam. These findings correlated with response when comparing initial to pre-surgical MRI. In all responding patients, DIRI results revealed a decrease in the number of regions over the breast in which the 0.2Hz frequency dominated. Similarly, DIRI evaluation according to area of average temperature in the region of interest compared between breasts was concordant in patients with response to therapy. Conclusions: Assessment of response by physical exam, MRI, and DIRI were consistent. Preliminary data reveals that serial DIRI imaging can be an effective adjunctive tool. No significant financial relationships to disclose.