Lombardi, Davide1, Paderno, Alberto1, Giordano, Davide2, Taboni, Stefano1, Albano, Domenico3, Barbieri, Verter2, Spriano, Giuseppe4, Mercante, Giuseppe4, Nicolai, Piero1
1 Department of Otorhinolaryngology – Head and Neck Surgery, University of Brescia, Brescia, Italy
2 Otolaryngology Unit, Arcispedale “S. Maria Nuova”, Reggio Emilia, Italy
3 Department of Nuclear Medicine, University of Brescia, Brescia, Italy
4 Department of Otorhinolaryngology – Head and Neck Surgery, Istituto Nazionale dei Tumori “Regina Elena”, Rome, Italy
Background: Well-differentiated thyroid cancer (WDTC) is characterized by favorable disease course and excellent survival outcomes. However, patients with lateral neck nodal metastases have a lower loco-regional control (LRC) and therefore a more aggressive treatment is required. Furthermore, the impact on survival of aggressive histologic variants of WDTC in N1b patients is still to be defined.
Materials and Methods: A multi-centric retrospective analysis on patients who underwent therapeutic lateral neck dissection (ND) for WDTC between 1994 and 2015 was accomplished. Data were collected in a single database. Aggressive histologic variants (AHVs) included the following sub-types: tall-cell, Hurtle-cell, diffuse sclerosing, and WDTC with poorly differentiated areas.
Results: The study included a total of 352 patients. Three hundred and forty-one (84%) NDs were performed concomitantly with total thyroidectomy, 65 (16%) were salvage procedures. Five-year overall survival (OS), disease-specific survival (DSS), LRC, and metastasis-free survival (MFS) were 92.5%, 97.2%, 88.6%, and 86.3% in the entire cohort. AHVs, diagnosed in 40 (11.4%) patients, demonstrated a statistically significant impact on OS and DSS (p=0.007 and p=0.047, respectively). OS, DSS, LRC, and MFS in patients with AHVs were 82.2%, 93.6%, 80.3%, and 87.3%, respectively. Advanced age (>55 years) was the only significant factor affecting survival (OS, p<0.001; DSS, p=0.011) in the AHVs sub-group.
Discussion and Conclusion: Patients with lateral neck metastases from AHVs have a significantly lower survival than WDTC; nevertheless, total thyroidectomy and lateral neck dissection with postoperative radio-iodine treatment warrant satisfactory survival outcomes. Patients older than 55 years have a worse prognosis.