Safety and efficacy of thermal ablation for cervical metastatic lymph nodes in papillary thyroid carcinoma: A systematic review and meta-analysis.

Background: To evaluate the safety and efficacy of radiofrequency ablation (RFA), microwave ablation (MWA), and laser ablation (LA) for the treatment of cervical metastatic lymph nodes (CMLNs) of papillary thyroid carcinoma (PTC). Methods: The Pubmed, EMBASE, Web of Science, and Cochrane Library databases were searched for studies on the safety and efficacy of thermal ablations (RFA, MWA, and LA) for the treatment of CMLNs of PTC until March 30, 2022. A review of 334 potential papers identified 17 eligible papers including 312 patients. Fixed-effects model or random-effects model was used to evaluate the pooled proportions of volume reduction rate (VRR), complete disappearance, and recurrence, and pooled estimates of changes in the largest diameter, volume, and serum Tg after ablation. The pooled proportions of overall and major complications were calculated. Subgroup analysis based on treatment modalities. The heterogeneity among studies was analyzed by using Q statistics and inconsistency index I2 . MINORS scale was used to evaluate the quality of the studies. Results: 17 eligible studies were finally identified, including 312 patients and 559 CMLNs. The pooled proportions of VRR, complete disappearance and recurrence of CMLNs were 91.28% [95% confidence interval (CI): 86.60-95.97%], 67.9% [95% CI: 53.1-81.1%] and 7.8% [95%CI: 3.0-14.1%], respectively. The pooled estimates of changes in the largest diameter, volume and serum Tg were 8.12 mm [95%CI: 6.78-9.46 mm], 338.75 mm3 [95%CI: 206.85 -470.65 mm3] and 5.96 ng/ml [95%CI: 3.68-8.24 ng/ml], respectively. The pooled proportions of overall and major complications were 2.9% [95%CI: 0.3-7.1%] and 0.3% [95%CI: 0-1.9%], respectively. Significant between-study heterogeneity was observed for complete disappearance (P<0.01, I2 =88.6%), VRR (P<0.001, I2 =99.9%), recurrence (P=0.02, I2 =47.76%), overall complications (P<0.02, I2 =44.8%), and changes in the largest diameter (P < 0.001, I2 =82.6%), volume (P<0.001, I2 =97.0%), and serum Tg (P < 0.001, I2 =93.7%). Subgroup analysis showed heterogeneity of the VRR among the treatment modality (I2 range: 84.4-100%). The VRR of MWA was the highest (97.97%), followed by RFA (95.57%) and LA (84.46%) (P < 0.001). Conclusion: All thermal ablations were safe and effective for the treatment of CMLNs of PTC. However, each treatment had significant heterogeneity in VRR. Compared with RFA and MWA, LA was less effective in reducing the volume of CMLNs of PTC.

Evaluating the safety and efficacy of microwave ablation in treatment of cervical metastatic lymph nodes of papillary thyroid carcinoma compared to repeat surgery.

OBJECTIVE: To evaluate the safety and efficacy of microwave ablation (MWA) versus repeat surgery for treating metastatic lymph nodes (MLNs) in papillary thyroid carcinoma (PTC). METHODS: Between July 2017 and October 2020, 67 patients were enrolled in this retrospective study. 19 and 48 patients underwent MWA and repeat surgery, respectively. The primary and secondary endpoints were recurrence-free survival and complication rates, respectively. The largest diameter, volume and volume reduction ratio (VRR) were analyzed before and after MWA. The effects of different ablation powers on the largest diameter, volume and VRR were investigated. Pre and posttreatment variables (e.g., baseline characteristics, serum thyroglobulin [Tg] levels, hospitalization time, treatment costs, recurrence-free survival and complication rates) were compared between groups. RESULTS: The largest diameter and volume postablation at each follow-up were smaller than the preablation levels (p < 0.05), except at the 1-month follow-up (p > 0.05). The largest diameter, volume, and VRR among the different ablation powers were not significantly different (p > 0.05). The mean serum Tg levels and biochemical remission rates were not significantly different between the groups (p > 0.05). Compared to reoperation, MWA had a shorter hospitalization time and lower treatment cost (p < 0.001). Total and minor complications were higher in the reoperation group (p < 0.05), but major complications were comparable (p > 0.05). The recurrence-free survival rate between groups was not significantly different (p = 0.401). The 1- and 3-year recurrence-free survival rates were comparable between the groups. CONCLUSIONS: MWA may be a safe and effective alternative to repeat surgery for treating MLNs of PTC in select patients.

Comparative analyses of the fragmented mitochondrial genomes of wild pig louse Haematopinus apri from China and Japan.

The wild pig louse Haematopinus apri is one of the commonest ectoparasites of wild pigs. In the present study, the entire mitochondrial (mt) genome of wild pig louse H. apri from China was sequenced and compared with previously characterized wild pig louse H. apri from Japan. We identified all of the 37 mt genes in the wild pig louse H. apri from China which are on nine circular minichromosomes. Each mt minichromosome is 2.9 kb-4.2 kb size and contains 2-8 genes and one non-coding region (1543 bp-2534 bp). The number of minichromosomes, gene content and gene order in the both mt genomes of wild pig louse H. apri from China and Japan are the same. The identity of the both mt genomes (except for non-coding regions) was 98.3% between wild pig louse H. apri from China and Japan. The entire mt genome sequence (except for non-coding regions) of wild pig louse H. apri from China is longer (3 bp) than that from Japan. For the 13 protein-coding genes, this comparison showed sequence differences in each gene at both the nucleotide (0.8%-2.4%) and amino acid (0.4%-3.5%) levels. The most conserved of these genes was the nad6, whereas the nad2 was least conserved at the nucleotide levels. This is the first comprehensive comparison of the mt genomes of a louse species from different geographic locations. This useful data provides additional genetic markers to study the phylogeny, systematics and population genetics of wild pig louse H. apri.

Analysis and evaluation of the efficacy of ultrasound-guided microwave ablation for papillary thyroid microcarcinoma.

OBJECTIVE: The choice of the most appropriate therapeutic approach for a diagnosed papillary thyroid microcarcinoma (PTMC) remains controversial. The present study aimed to evaluate the efficacy of microwave ablation (MWA) for unifocal PTMC with a diameter of ≤0.6 cm. METHODS: A total of 63 consecutive patients with PTMC treated with MWA were studied retrospectively. MWA was performed using the hydrodissection technique and multidimensional fixed-needle principle. We analyzed the absorption of the MWA area and evaluated the prognosis over a follow-up period of 24 months. In addition, 83 patients with PTMC who underwent surgery were selected. The operating room characteristics and procedural complications of the two groups were compared. RESULTS: In the MWA group, the volume of nodules (p < 0.05) decreased from 0.04 ± 0.03 cm3 to 0.0001 ± 0.0004 cm3 at the 24-month follow-up after MWA, and the volume reduction rate (p < 0.05) was 99.43 ± 1.58%. The incidence of temporary reactive hyperplastic lymphadenectasis was higher and that of other complications was lower in the MWA group than in the surgery group. One percent of the patients in the surgery group had recurrence or metastasis, but none were detected in the MWA group. The loss of thyroid tissue volume (p < 0.001), operating room time (p < 0.001), and the mean length of hospital stay (p < 0.001) were significantly lower in the MWA group than in the surgery group. CONCLUSION: Ultrasound-guided MWA is an effective treatment strategy for unifocal PTMC with a diameter of ≤0.6 cm.