Microwave ablation for painful chest wall metastases from gastrointestinal stromal tumor: a case report.

Background: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the digestive tract, with the potential to metastasize. Metastases to bone and soft tissue are more frequent in advanced cases, where targeted therapy is the standard treatment. However, around 10-15% of patients develop disease progression despite treatment. Studies have shown the efficacy of ablation in managing bone and soft tissue metastases (1, 2), but there are no reports of ablation for treating GIST bone or soft tissue metastases. Case presentation: In 2022, a 58-year-old man complaining of left back pain was admitted to Sichuan Cancer Hospital. He had undergone radical resection of the primary gastric GIST and vertebral metastases in 2014 and 2018, respectively. In 2019, rib metastases still occurred despite the use of targeted therapy. During the course of radiotherapy, targeted therapy, and immunotherapy, he experienced persistent chest wall pain. In addition, new lesions occurred in the lungs and chest wall in 2022. After a thorough assessment, microwave ablation (MWA) was recommended in response to his demand for immediate pain relief. The large rib metastasis constricted the spleen, so we completed the ablation in two sessions to reduce the risk of complications. He had 17 months of follow-up until September 2023, during which time his discomfort was considerably reduced. Conclusion: For GIST patients with soft tissue and bone metastases, MWA may offer substantial immediate pain alleviation. When other treatment procedures fail to achieve adequate efficacy, it provides an option.

Comparison of Micro-flow Imaging and Contrast-Enhanced Ultrasound in Ultrasound-Guided Microwave Ablation of Benign Thyroid Nodules.

OBJECTIVE: The study described here was aimed at ascertaining the utility of micro-flow imaging (MFI) during ultrasound (US)-guided microwave ablation (MWA) of thyroid nodules by contrasting its effectiveness with that of contrast-enhanced ultrasound (CEUS). METHODS: Seventy-three patients with eighty-eight thyroid nodules who underwent US-guided MWA were included in our study from January 2020 to June 2023. Thirty-five patients underwent CEUS during the MWA process, and thirty-eight patients underwent MFI during the MWA process. We compared the two groups' baseline characteristics, tumor volume (V), volume reduction rate (VRR), complications and clinical characteristics. RESULTS: Both groups exhibited similar outcomes with respect to V and VRR at 1, 3, 6, 12 and 18 mo after MWA (p > 0.05). Consistency was observed with respect to post-operative complications, supplementary ablation times and surgical duration (p > 0.05). It is worth noting that the MFI group had lower treatment costs compared with the CEUS group (11,337.64 ± 80.93 yuan for the MFI group versus 12,971.23 ± 254.89 yuan for the CEUS group, p < 0.05). CONCLUSION: In the MWA procedure for thyroid nodules, MFI is similar to CEUS with respect to safety and efficacy. Simultaneously, it offers the advantage of reducing surgical expenses, which lessens the economic burden for patients.

Protect the recurrent laryngeal nerves in US-guided microwave ablation of thyroid nodules at Zuckerkandl tubercle: a pilot study.

BACKGROUND: To evaluate the safety and efficacy of US-guided microwave ablation in patients with thyroid nodules at Zuckerkandl tubercle. METHODS: 103 consecutive patients with thyroid nodules at Zuckerkandl tubercle (ZTTN) were enrolled in this study from November 2017 to August 2021. Prior to the surgery or US-guided microwave ablation (MWA), preoperative ultrasound visualization of the recurrent laryngeal nerve (RLN) and ZTTN was performed, the size and the position relationship between them were observed. Patients were followed up at 1, 3, 6, and 12 months after MWA and the volume reduction rates (VRR) of the thyroid nodules were analyzed. RESULTS: All patients successfully had the RLN and ZTTN detected using ultrasound before surgery or ablation with a detection rate of 100%. For the 103 patients, the majority of ZTTN grades were categorized as grade 2, with the distance from the farthest outside of ZTTN to the outer edge of thyroid ranging between 6.0 and 10.0 mm. The position relationship between ZTTN and RLN was predominantly type A in 98 cases, with type D observed in 5 cases. After MWA, the median nodule volume had significantly decreased from 4.61 (2.34, 8.70) ml to 0.42 (0.15, 1.41) ml and the VRR achieved 84.36 ± 13.87% at 12 months. No nodules regrew throughout the 12-month follow-up period. Of the 11 patients experienced hoarseness due to RLN entrapment before ablation, 7 recovered immediately after separation of the RLN and ZTTN during MWA, 2 recovered after one week, and the other 2 recovered after two months. CONCLUSIONS: The RLN is closely related to ZTTN and mainly located at the back of ZTTN. The RLN can be separated from ZTTN by hydrodissection during MWA. US-guided MWA is a safe and effective treatment for ZTTN.

Ultrasound-guided percutaneous thermal ablation of parotid tumors: experience from two-centers.

Objective: To evaluate the efficacy and feasibility of ultrasound-guided percutaneous thermal ablation (TA) for treating benign parotid tumors.Methods: Patients with benign parotid tumors who underwent ultrasound-guided microwave ablation (MWA) or radiofrequency ablation (RFA) between January 2020 and March 2023 were included in this retrospective study. Change in tumor size (maximum diameter, tumor volume(V), volume reduction rate (VRR)) and cosmetic score (CS) were evaluated during a one-year follow-up period. We also recorded the incidence of any complications associated with TA.Results: A total of 23 patients (13 males and 10 females; median age 65 years, range 5-91 years) were included. The mean VRR at 1, 3, 6, and 12 months after TA was 37.03%±10.23%, 56.52%±8.76%, 82.28%±7.89%, and 89.39%±6.45%, respectively. Mean CS also changed from 3.39 ± 0.66 to 1.75 ± 0.93 (p < 0.001) by the end of follow-up time. Subgroup analysis showed that tumors with smaller initial maximum diameter had a faster CS reduction rate than those with larger initial diameter. The incidence of facial nerve dysfunction was 8.70%.Conclusion: Ultrasound-guided percutaneous TA is an effective and safe treatment option for patients with benign parotid tumors.

Combined multiple regional anesthesia for microwave ablation of liver Tumors: Initial experience.

OBJECTIVE: This study aims to assess the feasibility and safety of combined multiple regional anesthesia (CMRA) as a potential strategy to decrease pain and reliance on intravenous analgesics during and after ultrasound-guided microwave ablation (US-guided-MWA) of liver tumors. METHODS: A cohort of 75 patients with a total of 99 liver tumors who underwent US-guided-MWA of liver tumors were enrolled. These patients were randomly allocated into three groups: A, B, and C. Prior to the ablation procedure, Group A patients received a combination of hepatic hilar block (HHB), Transversus abdominis plane block (TAPB), and local anesthesia (LA). Patients in Group B were administered HHB in conjunction with LA, while those in Group C received TAPB and LA. Evaluative parameters included the Numerical Rating Scale (NRS) scores, consumption of morphine, incidence of complications, and factors influencing perioperative pain. RESULTS: All patients successfully underwent US-guided-MWA. The peak NRS scores for pain during ablation across the three groups were 2.36 ± 1.19, 3.28 ± 1.59, and 4.24 ± 1.42 respectively (P < 0.01), while the count of patients requiring morphine were 4/25, 8/25, and 13/25 respectively (P < 0.01). Postoperative NRS scores for the three groups at 4, 8, 12, 24, and 36-hour intervals demonstrated a pattern of initial increase followed by a decrease, with the order at each interval being: Group A < Group C < Group B. Factors associated with increased pain included larger tumor size, greater number of tumors, and longer procedure and ablation time (P < 0.05). No major complications were recorded across the three groups. CONCLUSION: CMRA offers an effective and safe modality to manage pain during and after US-guided-MWA of liver tumors.

Aluminum phytotoxicity induced structural and ultrastructural changes in submerged plant Vallisneria natans.

Aluminum (Al) is a concentration-dependent toxic metal found in the crust of earth that has no recognized biological use. Nonetheless, the mechanism of Al toxicity to submerged plants remains obscure, especially from a cell/subcellular structure and functional group perspective. Therefore, multiple dosages of Al3+ (0, 0.3, 0.6, 1.2, and 1.5 mg/L) were applied hydroponically to the submerged plant Vallisneria natans in order to determine the accumulation potential of Al at the subcellular level and their ultrastructural toxicity. More severe structural and ultrastructural damage was determined when V. natans exposed to ≥ 0.6 mg/L Al3+. In 1.2 and 1.5 mg/L Al3+ treatment groups, the total chlorophyll content of leaves significantly reduced 3.342, 3.838 mg/g FW, some leaves even exhibited chlorosis and fragility. Under 0.3 mg/L Al3+ exposure, the middle-age and young leaves were potent phytoexcluders, whereas at 1.5 mg/L Al3+, a large amount of Al could be transferred from the roots to other parts, among which the aged leaves were the most receptive tissues (7.306 mg/g). Scanning/Transmission electron microscopy analysis displayed the Al-mediated disruption of vascular bundle structure in leaf cells, intercellular space and several vegetative tissues, and demonstrated that Al in vacuole and chloroplast subcellular segregation into electron dense deposition. Al and P accumulation in the roots, stolons and leaves varied significantly among treatments and different tissues (P < 0.05). Fourier transform infrared spectroscopy of plant biomass also indicated possible metabolites (amine, unsaturated hydrocarbon, etc.) of V. natans that may bind Al3+. Conclusively, results revealed that Al3+ disrupts the cellular structure of leaves and roots or binds to functional groups of biological tissues, thereby affecting plant nutrient uptake and photosynthesis. Findings might have scientific and practical significance for the restoration of submerged vegetation in Al-contaminated lakes.

Effects and mechanisms of land-types conversion on greenhouse gas emissions in the Yellow River floodplain wetland.

The mechanism and extent of changes in greenhouse gas (GHG) emissions from seasonal river-floodplain wetlands subjected to land-type conversion are unknown. We monitored GHG fluxes and characterized soil microbial communities in four types of wetland (Riverside lower-beach wetland (RLW), Riverside higher-beach wetland (RHW), Cultivated wetland (CW), Mesophytic wetland (MW)) in the Yellow River flood land. Results revealed that land reclamation activities altered the distribution patterns of carbon (C) and nitrogen (N) in soil, as well as the structure and activities of microbial communities, leading to changes in the GHG emissions. Cumulative CO2 and N2O emissions were highest in CW, which were 2.10-10.71 times and 3.19-8.61 times greater than the other three wetlands, respectively, whereas cumulative CH4 emissions were highest in RLW (1850.192 mg·m-2). CW exhibited the highest 100-years-scale Global Warming Potential (GWP100-CO2-eq) (81.175 t CO2-eq·ha-1), which was 9.93, 3.12, and 2.11 times greater than RLW, RHW, and MW. Moreover, reclaiming riverside wetland as farmland will increase CO2 and N2O emission fluxes by 54.546-72.684 t·ha-1 and 2.615-2.988 kg·ha-1, respectively. 16S rRNA high throughput sequencing revealed that bacterial community composition changed significantly overtime and seasons. GHG fluxes showed a significant positive linear correlation with bacterial OTUs (y = 0.71x-319.4, R2 = 0.304) and Shannon index (y = 228.62x-796.6, R2 = 0.336). Structure equation models indicated that soil C, N and moisture content were the primary factors influencing bacterial community evolution, which had an impact on GHG fluxes. Actinomycetes were significantly affected by total carbon (TC) content, dissolved organic carbon (DOC), and C/N, while ammonia oxidizing and nitrifying bacteria were greatly influenced by NO3--N rather than TN and NH4+-N content. Opportunities exist to reduce GHG emissions and mitigate climate change by maintaining the original state of riverside wetland or restoring cultivated land to wetland in the Yellow River floodplain wetland.