Endocrine Abstracts

Introduction, material and methods: The BRAF isoform of RAF has been implicated in the pathogenesis of papillary thyroid cancer, but not of benign or follicular neoplasms. Also, BRAF mutations may confer a worse clinical prognosis than for papillary thyroid cancer without the BRAF mutation. Recurrence occurs more frequently when BRAF mutations are present. In addition, BRAF mutations are associated with extrathyroidal invasion, lymph node metastases, and advanced tumour stage at initial surgery. We have collected the data of our patients with differentiated thyroid cancer during the period from 2000 to 2015. In this study we have mainly compared the frequency of extrathyroidal invasion and lymph node metastases at initial surgery, and recurrences during the follow-up; depending if the patient is affected or not with BRAF V600E mutation. Clinical relevancies have been indicated through prevalence ratio(PR), and statistical differences have been indicated through confidence interval at 95%. Statistical analysis was made with Stata14.

Results: A total amount of 41 valid cases of papillary thyroid cancer were diagnosed during the period from 2000 to 2015. 22 (53.66%) patients were carriers of the BRAF V600E mutation and 19 (46.34%) were not. We compared the patients affected of the mutation with the non-carriers and these were the results: in the case of lymphadenopathies, we have not seen clinically relevant differences (PR 0.87) nor statistically significant (95% CI 0.43 – 1.77). About extrathyroidal invasion, we have not seen clinically relevant differences (PR 0.77) or statistically significant (95% CI 0.27 – 2.24) either. We have not seen either clinically relevant differences (PR 1.22) or statistically significant (95% CI 0.41 – 3.69) in the case of the recurrences. There were not clinically relevant or statistically significant differences in other variables such as multifocality (PR 0.95 (95% CI 0.44 – 2.04)) or the size of the tumour (6.57 mm (95% CI - 0.77 – 13.91)).

Conclusions: In our patients affected by papillary thyroid carcinoma, we have not seen poorer clinical outcomes such as tumour size, lymphadenopathies, extrathyroidal invasion, distant metastasis or mortality. However, the little size of the sample can subtract statistical power from the study. Also, the fact that it is a raw analysis does not allow the adjustment of potential confounding factors that could mitigate the effect.