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We aim to assess the safety and efficacy of proxalutamide, a novel androgen receptor antagonist, for men with metastatic castration-resistant prostate cancer (mCRPC) in a multicenter, randomized, open-label, phase 2 trial. In our study, the enrolled mCRPC patients were randomized to 100, 200 and 300 mg dose groups at 1:1:1. The primary efficacy endpoint was prostate-specific antigen (PSA) response rate. The secondary endpoints included objective response rate (ORR), disease control rate (DCR) and time to PSA and radiographic progression. Safety and pharmacokinetics were also assessed. Finally, there were 108 patients from 17 centers being enrolled. By week 16, there were 13 (35.1%), 12 (36.4%) and 15 (42.9%) patients with confirmed 50% or greater PSA decline in 100 mg (n = 37), 200 mg (n = 33) and 300 mg (n = 35) groups, respectively. Among the 19 patients with target lesions at study entry, three (15.8%) had a partial response and 12 (63.2%) had stable disease. The ORRs of 20.0%, 22.2%, 0% and DCRs of 80.0%, 88.9%, 60.0% were, respectively, achieved in 100, 200 and 300 mg groups. By the maximum follow-up time of 24 weeks, there were 42.6% and 10.2% of cases experiencing PSA progression and radiographic progression, respectively. Overall, adverse events (AEs) were experienced by 94.4% of patients, most of which were mild or moderate. There were 28 patients experiencing ≥grade 3 AEs. The most common AEs were fatigue (17.6%), anemia (14.8%), elevated AST (14.8%) and ALT (13.0%), decreased appetite (13.0%). These findings preliminarily showed the promising antitumor activity of proxalutamide in patients with mCRPC with a manageable safety profile. The proxalutamide dose of 200 mg daily is recommended for future phase 3 trial (Clinical trial registration no. CTR20170177).  相似文献   
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A high risk of developing second primary malignancy (SPM) has been reported among head and neck cancer patients. Here, we aimed to statistically quantify the impact of SPM development on the survival of head and neck cancer patients. Our study was conducted using the Surveillance, Epidemiology and End Results database to collect the data of 48 316 patients who received curative surgical resection for initial primary head and neck squamous cell carcinoma (IP-HNSCC) in 1975 to 2019. SPM diagnosis was treated as a time-varying covariate and multivariable Cox regression analysis was conducted to estimate the association between SPM development and survival, overall or by the subsite of IP-HNSCC. Of the included patients, 11 238 patients (23.3%) developed SPM during the follow-up period. A significant reduction in survival was observed among patients with SPM (hazard ratio [HR] for overall survival, 3.30; 95% confidence interval [CI]: 3.20-3.41). The impact of SPM development on reduced survival was more significant in patients with localized IP-HNSCC vs regional IP-HNSCC (HROS, 3.41; 95% CI: 3.24-3.6 vs HROS, 3.18; 95% CI: 3.05-3.31; P for interaction <.001). The survival impact of SPM development was more evident in younger patients than in older patients. SPM in lung and bronchus was associated with the most pronounced reduction in survival, overall and across all subsites of HNSCC. Our results indicated that SPM development led to a significant reduction in survival. A greater survival benefit may be achieved through intensive surveillance for SPM in lung and bronchus targeting younger patients and those with localized HNSCC.  相似文献   
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KEYNOTE-033 (NCT02864394) was a multicountry, open-label, phase 3 study that compared pembrolizumab vs docetaxel in previously treated, programmed death-ligand 1 (PD-L1)-positive, advanced non-small cell lung cancer (NSCLC), with most patients enrolled in mainland China. Eligible patients were randomized (1:1) to pembrolizumab 2 mg/kg or docetaxel 75 mg/m2 every 3 weeks. Primary endpoints were overall survival (OS) and progression-free survival and were evaluated sequentially using stratified log-rank tests, first in patients with PD-L1 tumor proportion score (TPS) ≥50% and then in patients with PD-L1 TPS ≥1% (significance threshold: P < .025, one-sided). A total of 425 patients were randomized to pembrolizumab (N = 213) or docetaxel (N = 212) between 8 September 2016 and 17 October 2018. In patients with a PD-L1 TPS ≥50% (n = 227), median OS was 12.3 months with pembrolizumab and 10.9 months with docetaxel; the hazard ratio (HR) was 0.83 (95% confidence interval [CI]: 0.61-1.14; P = .1276). Because the significance threshold was not met, sequential testing of OS and PFS was ceased. In patients with a PD-L1 TPS ≥1%, the HR for OS for pembrolizumab vs docetaxel was 0.75 (95% CI: 0.60-0.95). In patients from mainland China (n = 311) with a PD-L1 TPS ≥1%, HR for OS was 0.68 (95% CI: 0.51-0.89). Incidence of grade 3 to 5 treatment-related AEs was 11.3% with pembrolizumab vs 47.5% with docetaxel. In summary, pembrolizumab improved OS vs docetaxel in previously treated, PD-L1-positive NSCLC without unexpected safety signals; although the statistical significance threshold was not reached, the numerical improvement is consistent with that previously observed for pembrolizumab in previously treated, advanced NSCLC.  相似文献   
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Formal multidisciplinary team (MDT) discussions in clinical practice require time and space but have unclear survival benefits for advanced gastrointestinal cancer patients. Our study aimed to investigate the long-term survival of patients with advanced gastrointestinal cancer after MDT decision. From June 2017 to June 2019, continuous MDT discussions on advanced gastrointestinal cancer were conducted in 13 medical centers in China. MDT decisions and actual treatment received by patients were prospectively recorded. The primary endpoint was the difference in overall survival (OS) between patients in the MDT decision implementation and nonimplementation groups. The secondary endpoints included the implementation rate of MDT decisions and subgroup survival analysis. A total of 461 MDT decisions of 455 patients were included in our study. The implementation rate of MDT decisions was 85.7%. Previous treatment had an impact on MDT decision-making. The OS was 24.0 months and 17.0 months in the implementation and nonimplementation groups, respectively. The implementation of MDT decisions significantly reduced the risk of death in multivariate analyses (hazard ratio = 0.518; 95% confidence interval: 0.304-0.884, P = .016). Subgroup analysis showed a significant difference in survival of patients with colorectal cancer, but not in survival of patients with gastric cancer. The rate of secondary MDT discussion was only 5.6% among patients who the MDT decisions were discontinued due to changes in their condition. MDT discussion can prolong the OS of patients with advanced gastrointestinal cancer, especially those with colorectal cancer. Timely scheduling of the subsequent MDT discussion is necessary when the disease condition changes.  相似文献   
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Neoadjuvant programmed cell death protein 1 (PD-1) blockade exhibits promising efficacy in patients with mismatch repair deficient (dMMR) colorectal cancer (CRC). However, discrepancies between radiological and histological findings have been reported in the PICC phase II trial (NCT 03926338). Therefore, we strived to discern radiological features associated with pathological complete response (pCR) based on computed tomography (CT) images. Data were obtained from the PICC trial that included 36 tumors from 34 locally advanced dMMR CRC patients, who received neoadjuvant PD-1 blockade for 3 months. Among the 36 tumors, 28 (77.8%) tumors achieved pCR. There were no statistically significant differences in tumor longitudinal diameter, the percentage change in tumor longitudinal diameter from baseline, primary tumor sidedness, clinical stage, extramural venous invasion status, intratumoral calcification, peritumoral fat infiltration, intestinal fistula and tumor necrosis between the pCR and non-pCR tumors. Otherwise, tumors with pCR had smaller posttreatment tumor maximum thickness (median: 10 mm vs 13 mm, P = .004) and higher percentage decrease in tumor maximum thickness from baseline (52.9% vs 21.6%, P = .005) compared to non-pCR tumors. Additionally, a higher proportion of the absence of vascular sign (P = .003, odds ratio [OR] = 25.870 [95% CI, 1.357-493.110]), nodular sign (P < .001, OR = 189.000 [95% CI, 10.464-3413.803]) and extramural enhancement sign (P = .003, OR = 21.667 [2.848-164.830]) was observed in tumors with pCR. In conclusion, these CT-defined radiological features may have the potential to serve as valuable tools for clinicians in identifying patients who have achieved pCR after neoadjuvant PD-1 blockade, particularly in individuals who are willing to adopt a watch-and-wait strategy.  相似文献   
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目的探讨经导管主动脉瓣植入(TAVI)术前合并心房颤动(房颤)是否会对患者的预后产生影响。方法本研究为单中心回顾性研究。入选2016年5月至2020年11月于北部战区总医院住院并成功接受TAVI治疗且顺利出院的重度主动脉瓣狭窄患者115例。根据入选患者是否合并房颤将其分为房颤组(21例)及非房颤组(94例)。随访纳入患者的术后抗栓治疗情况及终点事件的发生情况, 终点事件为12个月的净不良心脑血管事件(NACCE), 包括心原性死亡、因心力衰竭再入院、非致死性心肌梗死、缺血性卒中及严重出血[出血学术研究联合会(BARC)定义的3~5型出血]。采用单因素logistic回归分析NACCE事件的相关因素。结果本研究共纳入115例成功接受TAVI并顺利出院的重度主动脉瓣狭窄患者, 年龄(73.8±6.9)岁, 男性63例, 其中21例(18.2%)在TAVI术前诊断为房颤。在术后抗栓治疗方面, 非房颤组患者中48.9%(46/94)接受了单药抗血小板治疗, 47.9%(45/94)接受了双联抗血小板治疗。房颤组患者中47.6%(10/21)使用抗凝药, 33.3%(7/21)接受了双联抗血小板...  相似文献   
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