Prophylactic Cranial Irradiation Versus Observation in Stage IV NSCLC Randomized Controlled Clinical Study

Group sample sizes of 72 in Group 1 and 72 in Group 2 achieve 90.140% power to detect a difference between the group proportions of 0.3100. The Group 2 proportion is 0.0700. The Group 1 proportion is assumed to be 0.1700 under the null hypothesis and 0.3800 under the alternative hypothesis. The test statistic used is the one-sided Z test (unpooled). The significance level of the test is 0.0250. For all patients with positive TKI detection, TKI combined with concurrent radiotherapy DT60-70Gy for the primary tumor. Imaging reexamination 2 months after TKI treatment confirmed the efficacy of CR, PR, and SD; meanwhile, reexamination of head MR Examination confirmed no intracranial metastasis. For all patients with negative TKI detection, the treatment mode was platinum-based regimen chemotherapy combined with concurrent radiotherapy for DT60-70Gy for the primary tumor. Imaging reexamination after 2 cycles of chemotherapy confirmed the efficacy of CR, PR, and SD, and skull MR Examination confirmed that there was no intracranial metastasis. Then,for the experiment arm,patients will receive prophylactic cranial irradiation DT: 30Gy/10f. Followed systematic imaging examinations in the first month following systemic treatment, every 3 months in 2 years, and every 6 months in 5 years. For the observation arm,without prophylactic cranial irradiation,Followed systematic imaging examinations in the first month following systemic treatment, every 3 months in 2 years, and every 6 months in 5 years. The primary end point was incidence of brain metastases（CBM）, PFS, and the secondary end point was OS、quality of life (QoL), concomitant neurocognitive disorders。