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Novel therapies for lung cancer are being explored nowadays with local therapies being the tip of the arrow. Intratumoral chemotherapy administration and local microwave ablation have been investigated in several studies. It has been previously proposed that lipiodol has the ability to modify the microenvironment matrix. In our current study we investigated this theory in BALBC mice. In total 160 BALBC mice were divided in eight groups: a) control, b) cisplatin, c) microwave, d) microwave and lipiodol, e) cisplatin and lipiodol, f) microwave and cisplatin, g) lipiodol and h) lipiodol, cisplatin and microwave. Lewis lung carcinoma cell lines (106) were injected into the right back leg of each mouse. After the 8th day, when the tumor volume was about 100mm3 the therapy application was initiated, once per week for four weeks. Magnetic resonance imaging was performed for each tumor when a mouse died or when sacrificed if they were still alive by the end of the experiment (8-Canal multifunctional spool; NORAS MRI products, Gmbh, Germany). Imaging and survival revealed efficient tumor apoptosis for the groups b,c,d,e and f. However; severe toxicity was observed in group h and no follow up was available for this group after the second week of therapy administration. Lipiodol in its current form does assist in a more efficient way the distribution of cisplatin, as the microwave apoptotic effect. Future modification of lipiodol might provide a more efficient method of therapy enhancement. Combination of drug and microwave ablation is possible and has an efficient apoptotic effect.
Microwave sensors in medical environments play a significant role due to the contact-less and non-invasive sensing mechanism to determine dielectric properties of tissue. In this work, a theranostic sensor based on Split Ring Resonators (SRRs) is presented that provides two operation modes to detect and treat tumor cells, exemplary in the liver. For the detection mode, resonance frequency changes due to abnormalities are evaluated, and in the treatment mode, microwave ablation is performed. The planar sensor structure can be integrated into a needle like a surgery tool that evokes challenges concerning size limitations and biocompatibility. To meet the size requirements and provide a reasonable operating frequency, properties of oval shaped SRRs are investigated. By elongating the radius of the SRR in one direction, the resonance frequency can be decreased significantly compared to circular SRR by a factor of two below 12 GHz. In order to validate the detection and treatment characteristics of the sensor, full wave simulations and measurements are examined. Clear resonance shifts are detected for loading the sensor structures with phantoms mimicking healthy and malignant tissue. For treatment mode evaluation, ex vivo beef liver tissue was ablated leading to a lesion zone 1.2 cm × 1 cm × 0.3 cm with a three minute exposure of maximum 2.1 W
The purpose of this study is to compare the efficacy and safety of microwave ablation (MWA) versus laser-induced thermotherapy (LITT) as a local treatment for hepatocellular carcinoma (HCC,) with regard to therapy response, survival rates, and complication rates as measurable outcomes. This retrospective study included 250 patients (52 females and 198 males; mean age: 66 ± 10 years) with 435 tumors that were treated by MWA and 53 patients (12 females and 41 males; mean age: 67.5 ± 8 years) with 75 tumors that were treated by LITT. Tumor response was evaluated using CEMRI (contrast-enhanced magnetic resonance imaging). Overall, 445 MWA sessions and 76 LITT sessions were performed. The rate of local tumor progression (LTP) and the rate of intrahepatic distant recurrence (IDR) were 6% (15/250) and 46% (115/250) in the MWA-group and 3.8% (2/53) and 64.2% (34/53) in the LITT-group, respectively. The 1-, 3-, and 5-year overall survival (OS) rates calculated from the date of diagnosis were 94.3%, 65.4%, and 49.1% in the MWA-group and 96.2%, 54.7%, and 30.2% in the LITT-group, respectively (p-value: 0.002). The 1-, 2-, and 3-year disease-free survival (DFS) rates were 45.9%, 30.6%, and 24.8% in the MWA-group and 54.7%, 30.2%, and 17% in the LITT-group, respectively (p-value: 0.719). Initial complete ablation rate was 97.7% (425/435) in the MWA-group and 98.7% (74/75) in the LITT-group (p-value > 0.99). The overall complication rate was 2.9% (13/445) in the MWA-group and 7.9% (6/76) in the LITT-group (p-value: 0.045). Based on the results, MWA and LITT thermal ablation techniques are well-tolerated, effective, and safe for the local treatment of HCC. However, MWA is recommended over LITT for the treatment of HCC, since the patients in the MWA-group had higher survival rates.