Which steroid works best for brain tumor swelling during radiation? new study aims to find out

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * 1\. 18 ≤ age ≤ 75 years old, gender not limited, generally acceptable, 40 ≤ KPS ≤ 80 points, the main reason for the patient's limited functional status is related neurological symptoms caused by edema of brain metastases; 2. Confirmed by cranial MRI or CT imaging, there is at least one brain metastasis with cerebral edema or neurological symptoms. All patients are scheduled to undergo WBRT (30 Gy/10f or 20 Gy/5f) or SBRT (20-40 Gy/1-6f, with ≤ 5 brain metastases and a maximum diameter of ≤ 5cm per lesion); 3. Expected survival of ≥ 3 months; 4. Having sufficient cognitive and understanding abilities, able to cooperate with scale assessments, and able to sign a written informed consent form (ICF); 5. Baseline neurological symptoms are stable (no need for emergency surgical decompression), and if surgery/radiotherapy has been performed, the following conditions must be met: postoperative/radiotherapy interval ≥ 4 weeks; 6. Baseline blood glucose/metabolism is controllable (e.g., HbA1c ≤ 8.0% in diabetes patients;If HbA1c is high, endocrinology evaluation is required and written permission for enrollment is granted. Exclusion Criteria: * 1\. Immediate surgical decompression is required, or there may be progressive cerebral herniation, intracranial pressure crisis, or life-threatening intracranial space occupying lesions present; 2. Has received systemic corticosteroid treatment within 7 days prior to the start of the study medication (such as due to the treatment of systemic lupus erythematosus, bronchial asthma, etc.); 3. Recent cranial surgery or radiation therapy (\<4 weeks); 4. Individuals with contraindications to glucocorticoids or severe immunosuppression; 5. Suffering from serious basic diseases such as uncontrolled hypertension and diabetes (HbA1c\>8%), untreated mental illness, active gastric ulcer, heart failure (NYHA III-IV grade), etc; 6. Pregnant/lactating women; 7. Unable to complete the primary assessment scale (severe cognitive/behavioral impairment) or unable to sustain Follow up period (e.g. no fixed address, difficult to ensure follow-up); 8. Participated in other intervention therapy trials within the past 4 weeks (which may affect the evaluation results), or is currently receiving drugs that may have serious drug interactions with the investigational drug; 9. Other serious systemic diseases or unsuitability.