Utilization mechanism of foam flooding and distribution situation of residual oil in fractured-vuggy carbonate reservoirs

The development of fractured-vuggy carbonate reservoirs is extremely difficult because of the complex fractured-vuggy structure and strong heterogeneity.Foam flooding is a potential enhanced oil recovery(EOR)technology in fractured-vuggy carbonate reservoirs.Based on the similarity criterion,three types of 2D visual physical models of the fractured-vuggy structure were made by laser ablation technique,and a 3D visual physical model of the fractured-vuggy reservoir was made by 3D printing technology.Then the physical analog experiments of foam flooding were carried out in these models.The experimental results show that foam can effectively improve the mobility ratio,control the flow velocity of the fluid in different directions,and sweep complex fracture networks.The effect of foam flooding in fractures can be improved by increasing foam strength and enhancing foam stability.The effect of foam flooding in vugs can be improved by reducing the density of the foam and the interfacial tension between foam and oil.Three types of microscopic residual oil and three types of macroscopic residual oil can be displaced by foam flooding.This study verifies the EOR of foam flooding in the fractured-vuggy reservoir and provides theoretical support for the application of foam flooding in fractured-vuggy reservoirs.

Prognostic value and predictive threshold of tumor volume for patients with locally advanced nasopharyngeal carcinoma receiving intensity-modulated radiotherapy

Background: Gross target volume of primary tumor(GTV?P) is very important for the prognosis prediction of patients with nasopharyngeal carcinoma(NPC), but it is unknown whether the same is true for locally advanced NPC patients treated with intensity?modulated radiotherapy(IMRT). This study aimed to clarify the prognostic value of tumor volume for patient with locally advanced NPC receiving IMRT and to ind a suitable cut?of value of GTV?P for prognosis prediction.Methods: Clinical data of 358 patients with locally advanced NPC who received IMRT were reviewed. Receiver oper?ating characteristic(ROC) curves were used to identify the cut?of values of GTV?P for the prediction of diferent end?points [overall survival(OS), local relapse?free survival(LRFS), distant metastasis?free survival(DMFS), and disease?free survival(DFS)] and to test the prognostic value of GTV?P when compared with that of the American Joint Committee on Cancer T staging system.Results: The 358 patients with locally advanced NPC were divided into two groups by the cut?of value of GTV?P as determined using ROC curves: 219(61.2%) patients with GTV?P ≤46.4 mL and 139(38.8%) with GTV?P >46.4 mL. The 3?year OS, LRFS, DMFS, and DFS rates were all higher in patients with GTV?P ≤46.4 mL than in those with GTV?P > 46.4 mL(all P < 0.05). Multivariate analysis indicated that GTV?P >46.4 mL was an independent unfavorable prognostic factor for patient survival. The ROC curve veriied that the predictive ability of GTV?P was superior to that of T category(P < 0.001). The cut?of values of GTV?P for the prediction of OS, LRFS, DMFS, and DFS were 46.4, 57.9, 75.4 and 46.4 mL, respectively.Conclusion: In patients with locally advanced NPC, GTV?P >46.4 mL is an independent unfavorable prognostic indi?cator for survival after IMRT, with a prognostic value superior to that of T category.

Clinical practice guidelines for modified radical mastectomy of breast cancer: Chinese Society of Breast Surgery (CSBrs) practice guidelines 2021

The proportion of patients with early-stage breast cancer undergoing mastectomy exceeds 70%in China/11 among which Auchincloss operation is the major surgical technique for patients with axillary lymph node positive breast cancer.In order to standardize the clinical application of modified radical mastectomy of breast cancer,Chinese Society of Breast Surgery(CSBrS)organized domestic experts to conduct literature retrieval and expert discussion on the theoretical basis and technical details of modified radical mastectomy for breast cancer.With reference to the grading of recommendations assessment,development,and evaluation system。

Clinical practice guidelines for multigene assays in patients with early-stage breast cancer: Chinese Society of Breast Surgery (CSBrS) practice guidelines 2021

The role of multigene assays in chemotherapy decision-making in patients with early invasive breast cancer has been widely recognized.In 2017,the American Society of Clinical Oncology(ASCO)clinical guidelines for multigene profiling assays focused on increasing the intensity of recommendations for the clinical use of MammaPrint®.[1]The 8th edition of the American Joint Committee on Cancer(AJCC)staging system,officially launched in 2018,established the concept of prognostic staging for the first time,adding the use of non-anatomical information to evaluate the prognosis.Initially,Oncotype Dx®was recommended for suitable patients based on Level I evidence.Subsequently,five testing techniques,Oncotype Dx®,MammaPrint®,EndoPredict®,PAM50®,and BCI,were formally incorporated into the system.[2]To assist breast disease specialists in China in their selection of appropriate multigene profiling assays and detection methods for patients,and also to instill caution on decision-making with reference to multigene assays,the Chinese Society of Breast Surgery(CSBrS)has,through literature investigation and expert discussion,provided information on the key clinical problems and guidelines for the use of multigene assays,evaluating the evidence with reference to the Grades of Recommendations Assessment Development and Evaluation(GRADE)system.Combined with the availability of these assays in China,the clinical practice guidelines for multigene assays were formulated and published.The purpose of this guideline is to provide a reference for clinicians specializing in breast diseases in China.