Aligning perspectives: towards a standardized concept of “complexity” in thyroid surgery. An international web-based survey

Introduction: Complication rates after thyroidectomy vary widely among centres. Various factors can affect the "complexity" of a case. However, an internationally agreed upon definition of what constitutes a "complex" case in thyroid surgery is currently lacking. We aimed to establish a framework supporting the development of a standardized definition of "complexity" in thyroid surgery by collecting endocrine surgeons' opinions through a survey. Materials and methods: A 28-item survey was distributed through the mailing lists of the Italian and European Societies of Endocrine Surgeons and via social media. Questions explored respondents' opinions on determinants and endpoint measures of "complexity". Responses were compared by unit and individual thyroidectomy volume (> 50 vs. < 50 cases/year), and by routine use of pre-operative ultrasound and intra-operative nerve monitoring. Results: Among 192 respondents, 97.3% acknowledged the potential usefulness of a shared definition of "complexity" in thyroid surgery for patients' workflow optimization. Permanent vocal-cord palsy (78.6%), operative duration (77.1%) and permanent hypoparathyroidism (77.1%) were most frequently chosen as appropriate endpoint measures of "complexity". Among determinants, previous neck surgery, adhesions/infiltration, mediastinal extension and large thyroid volume were considered impactful by the majority of respondents. High volume surgeons more frequently selected permanent palsy, tracheal injury and R1 margins as endpoints, and BMI as determinants of "complexity" (all Ps ≤ 0.05). Conclusion: Endocrine surgeons recognize the need for a standardized definition of "complexity" in thyroid surgery to enhance risk stratification and care. Perceived complexity varies with proficiency. Collected data support a reproducible framework, to be validated in future studies.