Discussion
skin burns, dysphonia, infection, tumour, endocrine malignancy, injury to vital neck organs, PTMC, gastric cancer
RECURRENCE, DISEASE, INFECTION, TUMOUR, NECK HEMATOMA, REGRESSION, GASTRIC CANCER
Many studies have shown that RFA has a good therapeutic effect in patients with PTMC. However, the description of the RFA treatment process in patients with PTMC in clinical guidelines is relatively empirical. The RFA power used for PTMC patients are varied from several watts to dozens watts among different medical institutions, so did the RFA time, for example. Although a large number of studies have shown that RFA can significantly benefit PTMC patients in terms of efficacy and quality of life, more energy is not always better in RFA surgeryPTMC is the most common endocrine malignancy worldwide, and its morbidity rate has increased significantly. The disease is usually asymptomatic, well-differentiated, less invasive, and unlikely to spread regionally. Although surgery remains the most common treatment for PTMC, many influential studies have shown that ultrasound-guided RFA is highly effective and safe for treating PTMCBy assessing the predictor–outcome correlation and decreasing the regression coefficients with the LASSO approach, six prospective clinical features were reduced to four viable predictors for the prediction model. This strategy outperformed the method of selecting predictors based on the strength of their univariable connection with the outcome, allowing a nomogram to be constructed from a panel of selected characteristics. Recent studies have incorporated multimarker analyses that combine individual markers into marker panels. Such as RNA sequencing and the clinical data of patients with gastric cancer revealed that the interaction of m6A alterations and lncRNAs may play a key role in predicting gastric cancer prognosis, shaping the tumour immune milieu, and predicting immune checkpoint inhibitor therapeutic responsesGiven that the RFA zone recovery time was comparable in the patient cohorts, the improved discrimination implies that the complex signature was robust for prediction and could be applied directly in the test cohort. In this study, we used our data to build a clinical model and provide a reference for clinical practice. The data of 176 patients with low-risk intrathyroidal PTMC were collected and randomly divided into the training and test groups. No instances of neck hematoma, skin burns, dysphonia, local infection, or injury to vital neck organs were observed in the whole corhort. Using LASSO regression analysis and Cox regression, we built a clinical model that can predict foci absorption time after RFA. By applying the log-rank test, we noted that the age of the patient, RFA energy, the average diameter of original tumour, and the average diameter of RFA zone at 1 month after ablation were prognostic variables for the RFA zone absorption time. In addition, the patient’s age above 49 years old, an ablation energy above 2800 J, an average diameter of original tumour above 0.6 cm, or the the average diameter of RFA zone above 1.1 cm at 1 month after ablation are risk factors for ablation foci healing within 12 months. These findings tell us that when a patient has the aforementioned risk factors, his/her expected RFA absorption time should be prolonged. In particular, we should note that there may be the best cut-off points for total energy during RFA in patients with low-risk intrathyroidal PTMC.The energy used in RFA surgery is very important. The RFA range need to be greater than the tumour edge to prevent marginal residue and recurrence. When all portions of the target ablation area had changed to transient hyperechoic zones, the ablation was terminatedStudy limitations include the fact that the nomogram was developed using retrospectively collected data from a cohort of patients at a single centre, and the sample size of the study was relatively small. Therefore, confounding bias, admission bias (Berkson bias), current case-new case bias (Nyman shift) are unavoidable in this study. Further research is needed to validate the performance of the nomogram in a larger external validation cohort.Taken together, our results highlight the vital factors that influence RFA zone absorption time. As a retrospective study, we developed a nomogram based on the clinical data. It can help doctors in risk assessment of patients and in careful planning of RFA procedure. The result of this study may provide a new view of RFA procedure.