Application of laser interstitial thermal therapy in the treatment of patients with euthyroid nodular goiter: aingle-center prospective study

Abstract

Background. Laser interstitial thermal therapy (LITT) is one of the most effective and economically justified methods, which is recommended as the first-line treatment for patients with compression syndrome, a significant cosmetic defect, and those who categorically refuse surgery or have contraindications to it. The purpose of the study was to analyze the short-term outcomes of LITT in patients with euthyroid nodular goiter. Materials and methods. The results of LITT were analyzed in 20 patients with euthyroid nodular goiter, Bethesda category II, and solid echostructure for 2021–2023. The average volume of nodules was 0.67 (0.16; 1.39) cm3. Medical GaAlAs diode laser VELAS II-30F was used. The response of the nodules was classified as positive effect if volume reduction rate (VRR) was above 70 %, absent with VRR 69–0 %, negative effect with VRR < 0 %. The total follow-up ranged from 1 to 24 months. Results. A linear regression analysis revealed that shrinkage of the final nodule volume after the first session (0.37 (0.06; 0.9) cm3) statistically significantly depended on the initial volume (0.67 (0.16; 1.39) cm3), R2 = 0.955, p < 0.001. A positive effect was observed only in nodules up to 1.0 cm3 (average of 0.16 (0.085; 0.31) cm3). Statistically significant correlation was not found after the first session between the effect and the initial nodule volume (r = –0.163, p = 0.49). A linear regression analysis showed the absence of statistically significant correlation between the final nodule volume, final VRR, and laser characteristics (p > 0.05). The final nodule volume after the second session decreased statistically significantly vs. initial one (p = 0.007) and vs. the final volume after the first session (p = 0.028). There was no statistically significant difference between the frequency of effect in patients after single LITT and in those with two sessions (χ2 = 2.14, p = 0.34). A linear regression analysis did not show statistically significant causal relationship between these indicators (R2 = 0.27, p = 0.12). Conclusions. Laser interstitial thermal therapy is a safe method of organ-preserving treatment in patients with the euthyroid nodular goiter, which can be performed on an outpatient basis and does not lead to thyroid dysfunction. LITT is the most effective with a volume nodule of up to 1.0 cm3. The use of LITT in nodules larger than 1.0 cm3 does not meet the criteria of technical “success” but this does not necessarily indicate the overall ineffectiveness since the sample volume was insufficient. For greater validity, a study should be conducted on a larger sample of patients, which will allow reliably assessing the effectiveness of the method and determining clear criteria of selecting patients for this intervention. The study is still in progress.