China’s oncology authorities released national guidelines standardizing how PET is used across cancer care, covering patient prep, tracer selection, acquisition protocols, and reporting metrics. The document designates 18F-FDG as the fundamental metabolic tracer for routine use, while also outlining targeted probe usage including 68Ga-PSMA and 68Ga-FAPI. A central operational aim is reducing scan-to-scan variability between hospitals by standardizing quantitative parameters such as SUV, MTV, and TLG. The guidance also frames PET indications across staging, therapy response, recurrence detection, prognosis assessment, and radiotherapy planning. For imaging-heavy trials and diagnostics, the guideline can materially affect comparability and downstream decision thresholds where PET measures are used for eligibility or response definitions.