P13 - Quality of life in patients with cystic thyroid nodules undergoing percutaneous ethanol injection: impact of treatment response after one year of follow-up

Background/Introduction Little attention has been paid to the impact of percutaneous ethanol injection (PEI) of cystic thyroid nodules (CTNs) on health- related quality of life (HRQoL). Purpose To evaluate thyroid-related and generic HRQoL, using the Thyroid-related Patient-Reported Outcome (ThyPRO)-39 and the Short Form health survey (SF)-36, before, six and twelve months after PEI for CTNs, respectively. Methods We conducted a prospective cohort study on consecutive patients treated with PEI for cytologically benign and symptomatic CTNs over a period of four years. The data were analyzed using the Friedman test, the Wilcoxon signed-rank test, adjusting the P-value by the Bonferroni method to account for multiple comparisons. Effect size for the Friedman test was reported using Kendall’s W coefficient, interpreted as small (0.1), moderate (0.3), or large (≥0.5). Multiple linear regression analyses were made to study the association between impaired general quality of life item of ThyPRO-39 and gender, age, body mass index (BMI). All tests were performed at the significant level of 0.05. Results We included 104 nodules [median volume 15.6 (7.0 - 32.0) mL] from 104 patients. We observed a volume reduction rate (VRR) of 82.6 (72.4 - 93.2) % and of 89.8 (77.3-97.5) %, six months and twelve months after PEI, respectively. Six and twelve months after treatment, ThyPRO-39 scores had largely (i.e., effect size > 0.5) and significantly (P value adjusted < 0.001) improved across all scales compared with baseline. Six and twelve months after treatment, SF-36 scores had largely and significantly (P value adjusted < 0.001) improved across all scales. Nodule size, but no gender, age or BMI, positively and significantly influenced (worsening) the general quality of life item of ThyPRO-39 at baseline, at 6-month and 12-month follow-up. Conclusion(s) PEI of symptomatic and benign CTNs is associated with a great improvement of HRQoL scores of ThyPRO and SF-36 at 6-month and 12-month follow-up. Both physical and mental domains of HRQoL are positively affected by PEI of CTNs. Risk factors of remaining HRQoL deficits one year after PEI need further exploration.