In this chapter, we delve into the therapeutic potential of 30.5 GHz millimetre waves on 3D glioblastoma organoids. We specifically investigated mildly thermal radiation effects in the context of new emerging focused energy deliver and bioelectromagnetic approaches. Our in-house developed exposure system, coupled with a rigorous dosimetry protocol and extensive multi-physics modelling, supported biological endpoints evaluation in terms of transcriptional profiling, cell morphological changes, and cell phenotypic characterization. Crucially, the induced thermal effect was minimal, aligning closely with our simulation models, and indicating the precise control of energy delivery. Notably, a 0.1 W power level enhanced the efficacy of Temozolomide, significantly increasing cell apoptosis while not affecting the differentiation status of glioblastoma organoid cells. This combination suggests a new avenue for glioblastoma treatment, leveraging millimetre wave-induced mechanisms that warrant further investigation. Our findings underscore the promise of this minimally-invasive technique, offering a glimpse into future glioblastoma therapies.