DBT-TOBI Scan in Monitoring Response to Chemotherapy before Surgery in Patients with HER2 Positive or Triple Negative Breast Cancer

PRIMARY OBJECTIVES:

I. To evaluate whether the total hemoglobin concentration ratio in the primary tumor versus (vs.) the surrounding tissue (HbTT/N), as estimated by our DBT-TOBI system, can be used as a metric to predict chemotherapy response.

II. Whether full mammographic compression period HbTT/N changes from baseline to just before cycle 3 are predictive of pathological complete vs non-complete responses (pCR vs non-pCR) for HER2+ and triple negative (TN) patients undergoing neoadjuvant chemotherapy, respectively.

SECONDARY OBJECTIVES:

I. To investigate whether other optical parameters are predictive of the final pathologic response (pCR vs. non-pCR).

II. To investigate the outcome prediction power of changes between baseline and just prior to the 2nd therapy cycle and between just before the change of agent and just before the 2nd cycle of therapy with the second agent, in applicable regimens.

III. To investigate the ability of optical metrics to predict residual cancer burden (RCB) 0/I vs RCB II/III outcome.

IV. To investigate whether optical property changes are associated with magnetic resonance imaging (MRI) volumetric imaging measurements between the time points prior to therapy and prior to the 3rd therapy cycle.

V. To investigate whether compression response based optical property metrics are associated with lesion stiffness as measured by MR elastography.

VI. To assess the threshold values for detecting pCR vs. non-PCR and RCB 0/I vs RCB II/III, respectively, for changes in optical parameters from baseline to just prior to the 3rd therapy cycle, from baseline to just prior to the 2nd therapy cycle, and from just before the change to just before the 2nd cycle of the second agent for applicable regimens.

VII. To assess the threshold values for detecting pCR vs. non-PCR and RCB 0/I vs RCB II/III, respectively, for changes in MR derived tumor morphology from baseline to just prior the 3rd therapy cycle.

VIII. To estimate the area under the receiver operating characteristic (ROC) curve (AUC) as an indicator of the ability of the changes in optical parameters to accurately identify patients with pCR vs. non-PCR and separately for patients with RCB 0/I vs RCB II/III, estimate the AUC as an indicator of the ability of the changes in MR derived tumor morphology to accurately identify patients with pCR vs. non-PCR and separately for patients with RCB 0/I vs RCB II/III, and compare the predictive abilities of these measures based on the difference in AUC, respectively.

OUTLINE:

Patients undergo DBT-TOBI scan over 30 minutes at baseline and before cycle 3 of chemotherapy. Patients may undergo optional DBT-TOBI scan before cycle 2 of chemotherapy and optional MRI-TOBI scan at baseline and before cycle 3 of chemotherapy. Patients whose regimen involves a change of chemotherapy agents along the treatment course undergo additional DBT-TOBI imaging scan before change and before cycle 2 after chemotherapy agents change.