Breast tumour response to PEGPH20-induced stromal modulation assessed by multiparametric MRI

Degradation of hyaluronan by PEGPH20 can improve stromal-dense tumour response to therapy. Given PEGPH20 treatment is associated with a reduction in tumour water content, we hypothesised that T₁, T₂, MTR and ADC may inform on PEGPH20 response. MRI was performed before and after PEGPH20 treatment in 4T1 HAS3 and MDA-MB-231 LM2-4 orthotopic breast tumours. T₁, T₂, and ADC significantly decreased, and MTR significantly increased following PEGPH20 treatment in 4T1 HAS3 tumours. PEGPH20 significantly decreased ADC but did not change T₁, T₂ or MTR in MDA-MB-231 LM2-4 tumours. These data suggest that ADC can detect breast tumour response to PEGPH20.