Numerical Investigation on the Effect of Different Physiological Cancerous Breast Parameters on the Output of Microwave Ablation

Author(s):  
Jatin Kumar ◽  
Ramjee Repaka

Abstract Microwave ablation (MWA) is a newly developed minimally invasive tumor therapy which possesses several advantages over the existing thermal therapies. Despite the several advantages, MWA also suffers same disadvantages similar to other thermal therapies like poor control over ablation volume. Sensitivity of different tissue parameters is the key factor to design a MWA protocol. In this work, sensitivity analysis has been conducted to quantify the effect of three cancerous breast parameters, viz., breast composition, tumor location, and tumor size, on the efficacy of MWA of breast cancer. Ablation volume has been taken as the indicator of the ablation efficacy during MWA procedure. A Taguchi's design of experimental approach has been utilized to optimize the number of simulations required for the analysis and then analysis of variance (ANOVA) has been performed to predict the most sensitive parameter along with their individual contribution. Finite element approach-based simulations have been performed in a multiphysics software. First, a grid-independent study has been established to optimize the number of mesh elements and to reduce the computational cost. Then, after finding the most optimum grid size, all the simulations have been performed in accordance with the protocol obtained from Taguchi's design of experiment approach and finally statistical analysis software has been used for analyzing Taguchi's design. It has been found that, the breast composition to be the most significant factor, with maximum contribution in ablation volume, among three considered factors followed by tumor location and tumor size, respectively.

2020 ◽  
Author(s):  
Zhiying Lin ◽  
Runwei Yang ◽  
Yawei Liu ◽  
Kaishu Li ◽  
Guozhong Yi ◽  
...  

Abstract Objective: Age is associated with the prognosis of glioma patients, but there is no uniform standard of age-group classification to evaluate the prognosis of glioma patients. In this study, we aimed to establish an age group classification for risk stratification in glioma patients. Methods: A total of 1502 patients diagnosed with gliomas at Nanfang Hospital between 2000 and 2018 were enrolled. The WHO grade of glioma was used as a dependent variable to evaluate the effect of age on risk stratification. The evaluation model was established by logistic regression, and the Akaike information criterion (AIC) value of the model was used to determine the optimal cutoff points for age-classification. The differences in gender, WHO grade, pathological subtype, tumor cell differentiation direction, tumor size, tumor location, and molecular markers between different age groups were analyzed. The molecular markers included GFAP, EMA, MGMT, p53, NeuN, Oligo2, EGFR, VEGF, IDH1, Ki-67, 1p/19q, PR, CD3, H3K27M, and TS. Results: The proportion of men with glioma was higher than that of women with glioma (58.3% vs 41.7%). Analysis of age showed that appropriate classifications of age group were 0-14 years old (pediatric group), 15-47 years old (youth group), 48-63 years old (middle-aged group), and ≥64 years old (elderly group).The proportions of glioblastoma and large tumor size (4-6 cm) increased with age (p = 0.000, p = 0.018, respectively ). Analysis of the pathological molecular markers across the four age groups showed that the proportion of patients with larger than 10% area of Ki-67 expression or positive PR expression increased with age (p = 0.000, p = 0.017, respectively). Conclusion: Age was effective evaluating the risk of glioblastoma in glioma patients. Appropriate classifications of age group for risk stratification were 0-14 years old (pediatric group), 15-47 years old (young group), 48-63 years old (middle age group) and ≥ 64 years old (elderly group). There was significant heterogeneity in WHO grade, tumor size, tumor location and some molecular markers among the four age groups.


Polymers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1312 ◽  
Author(s):  
Ali Farokhi Nejad ◽  
Roozbeh Alipour ◽  
Mozafar Shokri Rad ◽  
Mohd Yazid Yahya ◽  
Seyed Saeid Rahimian Koloor ◽  
...  

Polyurethane foams are one of the most common auxetic structures regarding energy absorption enhancement. This present study evaluates the result reliability of two different numerical approaches, the H-method and the P-method, to obtain the best convergence solution. A polymeric re-entrant cell is created with a beam element and the results of the two different methods are compared. Additionally, the numerical results compare well with the analytical solution. The results show that there is a good agreement between converged FE models and the analytical solution. Regarding the computational cost, the P-method is more efficient for simulating the re-entrant structure subjected to axial loading. During the second part of this study, the re-entrant cell is used for generating a polymeric auxetic cellular tube. The mesh convergence study is performed on the cellular structures using the H- and P- methods. The cellular tube is subjected to tensional and compressive loading, the module of elasticity and Poisson’s ration to calculate different aspect ratios. A nonlinear analysis is performed to compare the dynamic response of a cellular tube versus a solid tube. The crashworthiness indicators are addressed and the results are compared with equivalent solid tubes. The results show that the auxetic cellular tubes have better responses against compressive loading. The primary outcome of this research is to assess a reliable FE approach for re-entrant structures under axial loading.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Andrej Vranic ◽  
Frederic Gilbert

High-grade meningiomas are rare extra-axial tumors, frequently causing brain invasion and prominent brain edema. Patients harboring high-grade meningiomas occasionally present with behavior changes. Data about frequency and prognostic importance of preoperative behavior changes in patients with high-grade meningiomas is missing. 86 patients with primary high-grade meningiomas were analyzed. Statistical analysis was performed to determine correlation of preoperative behavior changes with tumor location, preoperative brain edema, tumor cleavability, tumor grade, Ki67 proliferation index, and microscopic brain invasion. Survival analysis was performed. 30 (34.9%) patients presented with preoperative behavior changes. These changes were more frequent with male patients (P=0.066) and patients older than 55 years (P=0.018). They correlated with frontal location (P=0.013), tumor size (P=0.023), microscopic brain invasion (P=0.015), and brain edema (P=0.006). Preoperative behavior changes did not correlate with duration of symptoms, tumor cleavability, tumor malignancy grade, and Ki67 proliferation index. They were not significantly related to overall survival or recurrence-free survival of patients with primary high-grade meningiomas. Preoperative behavior changes are frequent in patients harboring primary high-grade meningiomas. They correlate with tumor size, microscopic brain invasion, and brain edema. Preoperative behavior changes do not predict prognosis in patients with primary high-grade meningiomas.


2020 ◽  
Vol 7 ◽  
Author(s):  
Emi Mashima ◽  
Yu Sawada ◽  
Natsuko Saito-Sasaki ◽  
Kayo Yamamoto ◽  
Shun Ohmori ◽  
...  

Atypical lipomatous tumor (ALT) has been defined as a well-differentiated liposarcoma exhibiting a higher frequency of a local recurrence after surgical resection. ALT is mainly classified into deep type and superficial type. Compared with deep type ALT, superficial type ALT is rarely observed. One of the most important issues is that little has been known about superficial type ALT and it is not easy to predict the presence of superficial type ALT before surgical resection. To clarify the clinical manifestations of superficial type ALT, we examined 15 cases with superficial type ALT and 118 cases with benign lipoma, and analyzed their differences in clinical characteristics and the findings of MRI test. In clinical characteristics, the tumor size of superficial type ALT was significantly greater than that of benign lipoma, and superficial type ALT showed a significantly higher frequency of the tumor size of more than 4 cm. Superficial type ALT exhibited poor tumor mobility and hardness with elastic soft. In addition, a significantly higher frequency of tumor location of superficial type ALT was observed in extremities. Among tumor sites at the trunk, buttocks, and shoulder were high frequent location in superficial type ALT. In an MRI examination, superficial type ALT exhibited a significantly higher frequency of the septal structures compared with benign lipoma. The combinations of clinical characteristics, including physical examinations, MRI, and histological examinations, are helpful for the diagnosis of superficial type ALT.


BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Chunyan Zeng ◽  
Dandan Xiong ◽  
Fei Cheng ◽  
Qingtian Luo ◽  
Qiang Wang ◽  
...  

Abstract Background Estimating the risk of lymph node metastasis (LNM) is crucial for determining subsequent treatments following curative resection of early colorectal cancer (ECC). This multicenter study analyzed the risk factors of LNM and the effectiveness of postoperative chemotherapy in patients with ECC. Methods We retrospectively analyzed the data of 473 patients with ECC who underwent general surgery in five hospitals between January 2007 and October 2018. The correlations between LNM and sex, age, tumor size, tumor location, endoscopic morphology, pathology, depth of invasion and tumor budding (TB) were directly estimated based on postoperative pathological analysis. We also observed the overall survival (OS) and recurrence in ECC patients with and without LNM after matching according to baseline measures. Results In total, 473 ECC patients were observed, 288 patients were enrolled, and 17 patients had LNM (5.90%). The univariate analysis revealed that tumor size, pathology, and lymphovascular invasion were associated with LNM in ECC (P = 0.026, 0.000, and 0.000, respectively), and the multivariate logistic regression confirmed that tumor size, pathology, and lymphovascular invasion were risk factors for LNM (P = 0.021, 0.023, and 0.001, respectively). There were no significant differences in OS and recurrence between the ECC patients with and without LNM after matching based on baseline measures (P = 0.158 and 0.346, respectively), and no significant difference was observed between chemotherapy and no chemotherapy in ECC patients without LNM after surgery (P = 0.729 and 0.052). Conclusion Tumor size, pathology, and lymphovascular invasion are risk factors for predicting LNM in ECC patients. Adjuvant chemotherapy could improve OS and recurrence in patients with LNM but not always in ECC patients without LNM.


Sarcoma ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-8
Author(s):  
Jules Lansu ◽  
Winan J. Van Houdt ◽  
Michael Schaapveld ◽  
Iris Walraven ◽  
Michiel A. J. Van de Sande ◽  
...  

Background. The purpose of this study was to evaluate the overall survival (OS) and associated characteristics for patients with Myxoid Liposarcoma (MLS) over time in The Netherlands. Methods. A population-based study was performed of patients with primary localized (n = 851) and metastatic (n = 50) MLS diagnosed in The Netherlands between 1989 and 2016, based on data from the National Cancer Registry. Results. The median age of the MLS patients was 49 years, and approximately two-thirds was located in the lower limb. An association was revealed between age and the risk of having a Round Cell (RC) tumor. OS rates for primary localized MLS were 93%, 83%, 78%, and 66% after 1, 3, 5, and 10 years, respectively. The median OS for patients with metastatic disease at diagnosis was 10 months. Increasing age (Hazard Ratio (HR) 1.05, p=0.00), a tumor size >5 cm (HR 2.18; p=0.00), and tumor location (trunk HR 1.29; p=0.09, upper limb HR 0.83; p=0.55, and “other” locations HR 2.73; p=0.00, as compared to lower limb) were independent prognostic factors for OS. The percentage of patients treated with radiotherapy (RT) increased over time, and preoperative RT gradually replaced postoperative RT. In contrast to patients with localized disease, significant improvement of OS was observed in patients with metastatic disease over time. Conclusions. In this large nationwide cohort, tumor size and tumor location were independent prognostic factors for OS. Furthermore, a higher probability of an RC tumor with increasing age was suggested. An increased use of RT over the years did not translate into improved OS for localized MLS.


2020 ◽  
Vol 33 (Supplement_1) ◽  
Author(s):  
D Tian ◽  
X He ◽  
Y Yang ◽  
L Chen

Abstract   Recurrent laryngeal nerve lymph node metastasis (RLN LNM) is not rare in patients with esophageal cancer. We aimed to explore the risk factors for RLN LNM and to develop a nomogram predicting the likelihood of RLN LNM in esophageal squamous cell carcinoma (ESCC) patients. Methods We retrospectively reviewed patients with ESCC who underwent esophagectomy as well as recurrent laryngeal nerve lymph node dissection between May 2015 and February 2019 at two different institutions. The patients were divided into negative and positive groups according to the presence of RLN LNM. Risk factors for RLN LNM were evaluated by univariate and multivariate analyses. A nomogram was constructed for presentation of the final model. Results A total of 390 patients with ESCC were included in this study. The differences in tumor location, tumor differentiation, T stage, tumor size and carcinoembryonic antigen (CEA) between the negative (N = 270) and positive groups (N = 120) RLN LNM were significant (P < 0.05). Multivariate analysis indicated that the tumor location (OR = 0.520, 95% CI: 0.361–0.749, P < 0.001), tumor differentiation (OR = 2.279, 95% CI: 1.586–3.276, P < 0.001), T stage (OR = 1.436, 95% CI: 1.029–2.003, P = 0.033), tumor size (OR = 1.781, 95% CI: 1.021–3.106, P = 0.042) and CEA (OR = 1.206, 95% CI: 1.003–1.450, P = 0.046) were independent risk factors for RLN LNM. A nomogram with these variables had good predictive accuracy (c-index: 0.716). Conclusion Tumor location, tumor differentiation, T stage, tumor size and CEA may predict the risk of RLN LNM. We created a nomogram predicting the likelihood of RLN LNM in patients with ESCC.


2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 7558-7558
Author(s):  
S. I. Ou ◽  
J. A. Zell ◽  
A. Ziogas ◽  
H. Anton-Culver

7558 Background: Platinum-based adjuvant chemotherapy in randomized trials has failed to provide a survival benefit in stage I non-small-cell lung cancer (NSCLC). Using data from California Cancer Registry (CCR), we explored factors that have detrimental effect on survival in stage I NSCLC to identify a subset of patients at high risk for relapse and subsequent mortality. Methods: 19,702 stage I NSCLC cases in the CCR from 1989 to 2003 were identified and subgrouped into stage IA & IB disease. Patient demographic factors, tumor characteristics and treatment delivered were examined. Kaplan-Meier survival curves were calculated to estimate survival rates. Cox proportional hazards ratios were used to identify independent prognostic factors for survival. Results: Advanced age at diagnosis, male sex, low socioeconomic status (SES), non-surgical treatment & poorly-differentiated histologic grade (stage IA: hazard ratio [HR] = 1.14; 95% confidence interval [CI]: 1.08–1.19 & stage IB: HR = 1.11; 95% CI: 1.07–1.16) were factors identified with increased mortality risk on multivariate analysis. Non-upper lobe tumor location (RML/RLL/LLL) and tumor size ≥ 4 cm (vs < 4 cm; HR = 1.22; 95% CI: 1.15–1.30) were additional factors with increased mortality risk among stage IB patients. Conversely, bronchioloalveolar carcinoma (BAC)(vs adenocarcinoma: stage IA: HR = 0.81; 95% CI: 0.72–0.91 & stage IB: HR = 0.87, 95% CI: 0.77–0.98) & Asian ethnicity (vs Caucasian: stage IA: HR = 0.81, 95% CI: 0.70–0.94 & stage IB: HR = 0.80, 95% CI: 0.72–0.90) were associated with decreased mortality risk in stage I NSCLC. Lobectomy had the lowest HRs for death among all surgical techniques for both stage IA & IB NSCLC in the Cox proportional hazards model. Conclusions: Poorly-differentiated stage IA & IB NSCLC and stage IB NSCLC located in non-upper lobes or tumor size ≥ 4 cm carried an increased mortality risk on adjusted analysis. No significant financial relationships to disclose. [Table: see text]


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