The Medical Isotope Yttrium-90 segmentation by application delineates three principal demand drivers: Cancer Therapy, Diagnostic Imaging, and Research. Cancer Therapy dominates the market, accounting for roughly 70% of total volume, driven primarily by selective internal radiation therapy (SIRT) for hepatic malignancies and brachytherapy for prostate and breast cancers. This sub‑segment contributes the largest share of revenue because of high procedural frequency and reimbursement rates. Diagnostic Imaging represents about 20% of usage, where Y‑90’s beta emissions are leveraged in pre‑clinical imaging to validate therapeutic dosimetry, supporting precision oncology workflows. Although lower in absolute sales, this segment underpins clinical decision‑making and stimulates ancillary product demand. Research consumes the remaining 10%, encompassing radiochemistry development, pharmacokinetic studies, and novel carrier investigations. While modest in scale, research activity fuels pipeline expansion and long‑term market sustainability. Together, these application categories define the overall market size and shape strategic investment priorities across the Y‑90 ecosystem.