‘ONCOSENSOR’ for Noninvasive High-Specificity Breast Cancer Diagnosis by Carbogen-Enhanced Neutron Femto-Oximetry

Based on the first experiment on Differential Femto Oximetry (Paper 13270), we conducted a computer simulated study of the feasibility of conceptual design for our noninvasive malignancy probe, Oncosensor, to diagnose hypoxia of malignancy M = −0.90, measured by pO₂ — which correspond to volume averaged hypoxia M^′ = −0.09 — in 1cm, 3 cm and 5 cm DIA tumors embedded in the middle of a 10 cm DIA breast. M^′ is further masked by background γ’s from the in vivo tissue by factor x = 4.4–7 for subcutaneous and central tumor, respectively, to apparent M^″ = M^′/X which, in turn, renders hypoxia non-diagnosable for 1 cm tumors; marginally so for 3 cm ones with specificity S = 75%, and fully diagnosable with S = 95% in 5 cm ones. To diagnose 1–3 cm and smaller tumors, we propose to enhance M^″ by a factor of ≈ 3 by replacing air breathing with that of Carbogen (O₂ 95%, CO2 5%). With carbogen breathing, simulations predict hypoxia detection in 1 cm subcutaneous tumor with S = 68%, and in 3 cm ones with S = 95–99.9%. Carbogen renders possible 2 additional diagnostic tests for redundancy. Significant improvements of the above measurement accuracies are projected. Oncosensor will be tested in vivo with R3230 tumors in Fischer rats at UCI’s Center for Functional Onco-Imaging. Oncosensor requires imaging guidance.