Multicentric Thyroid Carcinoma: Epidemiological and Histological Analysis in a Cancer Reference Hospital

Background: The incidence of thyroid cancer has been increasing in recent years. The extent of thyroidectomy to treat these patients has been largely discussed. Besides, the study of multifocality of thyroid cancer becomes important, especially due to the inconsistency in the literature on related factors, such as recurrence, metastasis and prognosis. The main objective of this study is to describe and analyze the epidemiological and histological factors associated with multicentric thyroid carcinoma. Method: Cross-sectional, retrospective study collecting histological data from all patients who underwent total thyroidectomy for treatment of thyroid cancer in a cancer reference hospital, between January 2013 and December 2014. Results: 88 patients with histological diagnosis of thyroid cancer were recruited. Females accounted for 87.5% of cases, with mean age of 47.6 years old. Papillary carcinoma was diagnosed in 88% of patients. Tumors smaller than 2 cm accounted for 65.8% of cases, most of them non encapsulated (58%). One out of three patients had more than one focus of thyroid cancer. Lymph node metastasis were reported in 20% of patients. The presence of goiter in the specimen and non encapsulated tumors were significantly associated with multifocal thyroid cancer. Conclusion: Two or more thyroid cancer foci were reported in 33% of patients and were significantly associated with the absence of capsule around thyroid tumors (68.9%, n=20, p=0.04) and the presence of goiter (65.5%, n=19, p=0.01). The presence of tumor in the opposite lobe was identified in 24% of patients, in our series.