BACKGROUND: The incidence of well-differentiated thyroid cancer (WDTC) has increased in recent years. Despite its excellent prognosis, increasing morbidity from recurrent diseases continues to affect long-term outcomes. Among at-risk populations, Filipinos have the highest incidence of thyroid cancer worldwide, characterized by a highly aggressive and recurrent form of disease. Here, we sought to identify risk factors associated with disease recurrence among Filipinos with WDTC. METHODS: This retrospective cohort study examined 723 patients diagnosed with WDTC seen at Philippine General Hospital. Affected individuals were classified based on the presence or absence of disease recurrence. Multivariate logistic regression analyses were used to determine significant predictors of recurrence. RESULTS: Multiple risk factors, including age >45 years (odds ratio [OR], 1.44), multifocality of cancer (OR, 1.43), nodal involvement (OR, 4.0), and distant metastases at presentation (OR, 2.78), were significantly associated with a recurrence of papillary thyroid cancer (PTC). In contrast, follicular variant histology (OR, 0.60) and postsurgical radioactive iodine therapy (OR, 0.31) were protective for PTC recurrence. Distant metastases at presentation (OR, 19.4) and postsurgical radioactive iodine therapy (OR, 0.41) were associated with follicular thyroid cancer (FTC) recurrence. CONCLUSION: Lymph node metastases at presentation was the strongest predictor of recurrence in PTC, whereas distant metastases at presentation was the strongest for FTC recurrence. Among Filipinos, stratification of WDTC patients based on recurrence risk factors identified in this study will be helpful in guiding the intensity of treatment strategies and long-term thyroid cancer surveillance.
Cohort Studies ; Hospitals, General ; Humans ; Incidence ; Iodine ; Logistic Models ; Lymph Nodes ; Neoplasm Metastasis ; Prognosis ; Recurrence* ; Retrospective Studies ; Risk Factors* ; Thyroid Gland* ; Thyroid Neoplasms*

BACKGROUND: Well-differentiated thyroid cancer (WDTC) is the most common form of thyroid malignancy. While it is typically associated with good prognosis, it may exhibit higher recurrence and mortality rates in selected groups, particularly Filipinos. This paper aims to describe the experience of a Philippine Hospital in managing patients with differentiated thyroid cancer. METHODS: We performed a retrospective cohort study of 723 patients with WDTC (649 papillary and 79 follicular), evaluating the clinicopathologic profiles, ultrasound features, management received, tumor recurrence, and eventual outcome over a mean follow-up period of 5 years. RESULTS: The mean age at diagnosis was 44±13 years (range, 18 to 82), with a majority of cases occurring in the younger age group (<45 years). Most tumors were between 2 and 4 cm in size. The majority of papillary thyroid cancers (PTCs, 63.2%) and follicular thyroid cancers (FTCs, 54.4%) initially presented as stage 1, with a greater proportion of FTC cases (12.7% vs. 3.7%) presenting with distant metastases. Nodal metastases at presentation were more frequent among patients with PTC (29.9% vs. 7.6%). A majority of cases were treated by complete thyroidectomy, followed by radioactive iodine therapy and thyroid stimulating hormone suppression, resulting in a disease-free state. Excluding patients with distant metastases at presentation, the recurrence rates for papillary and FTC were 30.1% and 18.8%, respectively. CONCLUSION: Overall, PTC among Filipinos was associated with a more aggressive and recurrent behavior. FTC among Filipinos appeared to behave similarly with other racial groups.
Cohort Studies ; Diagnosis ; Follow-Up Studies ; Hospitals, General* ; Humans ; Iodine ; Mortality ; Neoplasm Metastasis ; Prognosis ; Recurrence ; Retrospective Studies ; Thyroid Gland* ; Thyroid Neoplasms* ; Thyroidectomy ; Thyrotropin ; Ultrasonography

Background and Objective: Epidemiological studies have shown that Filipinos have a higher prevalence of welldifferentiated thyroid cancer and a higher rate of recurrence. The BRAF V600E mutation has been proposed as a potential prognostic marker in aggressive papillary thyroid cancers. In this study, we determined whether this mutation is a risk factor for tumor recurrence in papillary thyroid cancer among Filipinos. Methods: We conducted an age and sex-matched case-control study of patients with papillary thyroid cancer; we had two groups – with and without tumor recurrence – of 14 patients each, with at least a 5-year follow-up. We extracted the DNA samples from the patients’ (paraffin-embedded) tumor biopsy tissue blocks from thyroidectomy specimens, then detected the BRAF V600E mutation using polymerase chain reaction. The McNemar’s test for difference of proportions in paired data was used to determine the association of BRAF V600E mutation with recurrence. Results: The BRAF V600E mutation was found in 57.14% of all cases. We found a prevalence of 64.29% among those with recurrence and 50.00% among those without recurrence, with no significant difference between the two groups (p = 0.688). Conclusion Our study showed the BRAF V600E mutation was not associated with recurrence. We encountered several limitations: we had limited data regarding molecular methodologies in the Philippine setting, we had a small sample size, and therefore we could not study other parameters (e.g., tumor characteristics, lymph node metastasis, stage of disease). We hope that this paves the way for future studies and collaborations to establish the role of BRAF V600E in Filipinos with papillary thyroid tumor recurrence.
papillary thyroid cancer ; molecular diagnostics ; tumor recurrence