1.Analysis of clinical prognosis and influencing factors of pathological complete response in patients with locally advanced esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy
Puchun ER ; Fangdong ZHAO ; Jiacheng LI ; Xi CHEN ; Jie DONG ; Tian ZHANG ; Wencheng ZHANG ; Ping WANG ; Qingsong PANG
Chinese Journal of Radiation Oncology 2024;33(5):413-418
Objective:To investigate the influencing factors of pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (NCRT) in patients with locally advanced esophageal squamous cell carcinoma (ESCC), and to compare the clinical prognosis of ESCC patients with and without pCR after NCRT (40 Gy/ 20F).Methods:Among patients enrolled in a prospective clinical study, 87 ESCC patients treated with NCRT followed by surgery in Tianjin Medical University Cancer Institute & Hospital between June 2015 and October 2019 were selected. They were divided into the pCR ( n=35) and non-pCR groups ( n=52). Clinicopathological characteristics were retrospectively analyzed and subsequent follow-up was performed. Clinical prognosis and influencing factors were compared between two groups by using Kaplan-Meier and Cox regression analyses. Results:After NCRT, 40% of the ESCC patients could achieve pCR. Univariate analysis showed that patients in the pCR group had a disease-free survival (DFS) of 39.3 months and an overall survival (OS) of 64.0 months. In comparison, patients in the non-pCR group had a DFS of only 14.1 months and an OS of only 25.2 months. The differences were statistically significant (DFS: P<0.01, OS: P<0.05). Multivariate analysis revealed that whether pCR or not after NCRT, age, number of primary lesions, evaluation results after NCRT and postoperative pathological outcomes were important prognostic factors. The differences were statistically significant between two groups (all P<0.05). Conclusion:pCR after NCRT is significantly correlated with long-time survival of patients with ESCC, and pCR after NCRT has an important value in predicting clinical prognosis for long-term survival of ESCC patients.
2.Compression Properties of Fat Layer under Impact Loading
Ronghua LIU ; Yaoke WEN ; Wenmin YAN ; Zhenyu BAO ; Fangdong DONG ; Junyu ZHOU
Journal of Medical Biomechanics 2022;37(2):E238-E243
Objective To study dynamic compression performance of adipose tissues, so as to further reveal the damage mechanism, and provide references for medical treatment.Methods Based on the improved split Hopkinson pressure bar (SHPB) experimental device, the adipose tissue dynamic compression experiment was conducted. The stress-strain curves of adipose tissues at different strain rates were obtained. Then the numerical model of SHPB was established, and the experimental process was simulated and analyzed. The numerical simulation for penetration process of 32 mm diameter rubber non-lethal projectile into the simulated target in human abdomen was carried out.Results Adipose tissues had a noticeable strain rate effect. The stress-strain curves at two high strain rates were approximately straight lines. The slope was similar, and the elastic modulus was 3.25 MPa, which was about 6 times of that under a quasi-static state. The simulation curves of fat SHPB were consistent with the experimental curves, which verified correctness of the constitutive model. In the process of non-lethal projectile penetrating human abdomen, an annular convex area similar to water wave appeared on skin surface, and the fat layer absorbed about 67% of the impact kinetic energy.Conclusions The experimental data of adipose tissues are very accurate. Numerical simulation can reproduce the penetration process well, and provide references for studying the damaging effect of non-lethal weapons on human body.