Recurrence factors in familial papillary thyroid carcinoma.

BACKGROUND

Papillary thyroid carcinoma (PTC) has classically been considered a sporadic carcinoma. However, a subgroup with familial clustering has been observed, which appears to present a poorer prognosis than the sporadic form. The aim of this study is to analyze the recurrence rates and prognostic factors for familial PTC (FPTC) treated with curative intent.

METHODS

Multicenter national study, endorsed by the Spanish Association of Surgeons. Study population: patients with FPTC (families who have at least 2 first-degree relatives with a confirmed PTC) who meet cure criteria after the treatment. Study endpoints: recurrence rate and risk factors for recurrence. Statistical analysis: Cox regression analysis and survival analysis.

RESULTS

The study included 252 cases with a mean follow-up of 90±68,9 months, recurrence in 26.9% (N.=68) and a disease-free survival of 183,46±7,8 months. In the multivariate analysis, the independent factors for the risk of recurrence were: 1) the number of patients with FPTC in the family (OR 1.165); 2) the multifocality (OR 2.525); 3) the vascular invasion (OR 2.770); and 4) TNM staging system (OR 5.128). In the reanalysis that included the American Thyroid Association (ATA) risk of recurrence, this variable was highly predictive of recurrence (OR 12.048).

CONCLUSIONS

FPTC presents a high recurrence rate, which is related to the number of cases of FPTC in the family, the presence of multifocality and vascular invasion, the TNM staging system and the ATA recurrence risk assessment.