Correlation and predictive value of pathological complete response and ultrasound characteristic parameters in neoadjuvant chemotherapy for breast

BACKGROUND Breast cancer ranks as one of the most prevalent malignant tumors among women,significantly endangering their health and lives.While radical surgery has been a pivotal method for halting disease progression,it alone is insufficient for enhancing the quality of life for patients.AIM To investigate the correlation between ultrasound characteristic parameters of breast cancer lesions and clinical efficacy in patients undergoing neoadjuvant chemotherapy(NAC).METHODS Employing a case-control study design,this research involved 178 breast cancer patients treated with NAC at our hospital from July 2019 to June 2022.According to the Miller-Payne grading system,the pathological response,i.e.efficacy,of the NAC in the initial breast lesion after NAC was evaluated.Of these,59 patients achieved a pathological complete response(PCR),while 119 did not(non-PCR group).Ultrasound characteristics prior to NAC were compared between these groups,and the association of various factors with NAC efficacy was analyzed using univariate and multivariate approaches.RESULTS In the PCR group,the incidence of posterior echo attenuation,lesion diameter≥2.0 cm,and Alder blood flow grade≥II were significantly lower compared to the non-PCR group(P<0.05).The area under the curve values for predicting NAC efficacy using posterior echo attenuation,lesion diameter,and Alder grade were 0.604,0.603,and 0.583,respectively.Also,rates of pathological stage II,lymph node metastasis,vascular invasion,and positive Ki-67 expression were significantly lower in the PCR group(P<0.05).Logistic regression analysis identified posterior echo attenuation,lesion diameter≥2.0 cm,Alder blood flow grade≥II,pathological stage III,vascular invasion,and positive Ki-67 expression as independent predictors of poor response to NAC in breast cancer patients(P<0.05).CONCLUSION While ultrasound characteristics such as posterior echo attenuation,lesion diameter≥2.0 cm,and Alder blood flow grade≥II exhibit limited predictive value for NAC efficacy,they are significantly associated with poor response to NAC in breast cancer patients.

Behavior of axially loaded tubular X-joints using bolted connection:mechanical model and validation

X-joints are one of the fundamental joint configurations used in a wide range of transmission tubular structures.Experimental investigation of four tubular X-joints with bolted connection was conducted in this study,and it was found that the annular plate was the main yielding control member of such X-joints.Moreover,the portion outside the effective width of the chord member still had a restriction effect on the annular plate,which led to reducing the yielding strength of the joint,while the gusset plate could help to improve the yield strength capacity.In the current design code of steel structures,the contribution to the strength capacity of the gusset plate has not been taken into account.Therefore,based on some mechanical assumptions,a general mechanical model was proposed.After the introduction of the gusset plate strength capacity factor,the yield capacity simplified calculation method of such X-joints was derived.Through the analyses of such X-joints with various diameters and thicknesses,it was concluded that a simple mechanical model could predict test results very well and that the contribution of the gusset plate was also taken into account.