Stereotactic aspiration combined with gamma knife radiosurgery for cystic brain metastasis / 中国微创外科杂志

ABSTRACT

Objective To evaluate the outcome of stereotactic aspiration combined with gamma knife radiosurgery in the treatment of cystic brain metastasis.Methods The study included 21 cases of cystic brain metastasis.There were 16 males and 5 females,with their age ranged 45～78 years old(mean,64.5 years old).Nineteen patients had a solitary tumor and 2 patients had two lesions.The mean diameter of tumors was 36 mm.The Karnofsky Performance Score(KPS) was ≥50%.A stereotactic aspiration was performed under CT guidance to drain the cystic fluid.Then the MASEP-SRRS gamma knife radiosurgery was performed.All brain metastasis were averagely enclosed within the 40%～65%(mean,50%) isodose shells of the radiosurgical fields with a peripheral dose of 16～22 Gy(mean,19.5 Gy).Results All the cases were followed for 1～3 months(mean,2.3 months) with CT or MRI scanning.Tumors completely disappeared in 12 lesions,subsided in 9 lesions,changed less than 10% in 1 lesion,and enlarged in 1 lesion.Cerebral necrosis and edema adjacent to lesions respectively developed in 1 case.No other severe complications were seen.The control rate of tumor was 95.7%(22/23).Twenty-one patients were followed for 6～36 months(mean,23.5 months).The followed-up results showed improvement of symptoms in 18 cases,no change in 2 cases,and exacerbation in 1 case.The survival rate at 6 months was 90.5%(19/21).And the 1-and 2-year survival rates were 62.5%(10/16) and 25%(3/12),respectively.One case survived beyond 3 years.The median survival time was 14.1 months.Conclusions Stereotactic aspiration combined with gamma knife radiosurgery is an ideal treatment for cystic brain metastasis.