Factors Influencing the Presence of Remnant Thyroid Tissue After Thyroidectomy for Differentiated Thyroid Carcinoma

Differentiated thyroid carcinoma (DTC) is the most common endocrine malignancy. The study was performed to evaluate the factors that are likely to be responsible for the presence of remnant thyroid tissue. The data of 183 patients who underwent total thyroidectomy for DTC were retrospectively reviewed. The remnant thyroid tissue was determined by technetium-99 m pertechnetate (Tc-99 m) scintigraphy. The association of all possible factors (age, gender, size, multifocality, type, and characteristics of the tumor), extension of thyroidectomy, postoperative serum thyroglobulin (Tg), Tg antibody, and thyroid stimulating hormone levels with the presence of remnant tissue was evaluated. Remnant thyroid tissue was more common in patients with intermediate or high-risk features compared to low-risk group (p < 0.001) and in patients who underwent total thyroidectomy compared to patients with total thyroidectomy and central lymph node dissection (p = 0.009). Age, gender, and size, multifocality, type, and characteristics of the tumor were not found to be associated with the presence of remnant tissue. The extent of surgery is the single independent factor for the presence of remnant thyroid tissue after thyroidectomy (p < 0.001). The patients with intermediate and high-risk and extensive surgery were more likely to have remnant thyroid tissue after thyroidectomy for DTC.