Comparison of the Therapeutic Effects of Methylprednisolone and Dexamethasone on Peritumoral Edema During Radiotherapy for Brain Metastases:

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.