Long-term follow-up for patients with papillary thyroid carcinoma treated as benign nodules

BACKGROUND: The recent prevalence of ultrasonography and fine-needle aspiration biopsy (FNAB) has facilitated the detection and diagnosis of papillary thyroid carcinoma. However, there are still cases that are preoperatively misdiagnosed and treated as benign nodules because ultrasonographic and FNAB findings do not provide sufficient evidence for a malignant diagnosis. In this study, we investigated the clinical outcomes of patients with papillary carcinoma that had not been recognized preoperatively. PATIENTS AND METHODS: We investigated the prognoses of 56 patients with papillary carcinoma who underwent thyroidectomy without node dissection under a diagnosis of benign nodules. RESULTS: None of the patients underwent further surgery such as completion total thyroidectomy and node dissection after the pathological diagnosis of papillary carcinoma was established. However, to date, only 3 patients (5.3%) showed recurrence 116, 133 and 148 months after the initial surgery, respectively. Two patients showed recurrence in the remnant thyroid and one showed recurrence in the bone. None of the patients have died of thyroid carcinoma. CONCLUSION: Papillary carcinomas misdiagnosed as benign nodules on ultrasonography and FNAB are indolent and very slow-growing. Immediate further surgery is not needed for such cases, even if they were resected as benign nodules at the initial surgery.