Single lobe disease in cases of advanced endemic goiter: a new phenotype.

OBJECTIVES To report a new phenotype of advanced endemic goiter that affects only one lobe of the thyroid gland. PATIENTS AND METHODS This study included 60 patients from the west of Sudan with long-standing unilateral simple endemic goiter that required obectomy, with emphasis on the gross appearance, measurements and cytological features of the contralateral lobe. RESULTS Out of 60 patients with unilateral goiter, 50 (83%) were found to have the disease on the ipsilateral lobe only (monolobar goiter). The contralateral lobe in these 50 patients showed no nodularity, and its volume was within the normal limits. All patients with monolobar disease had total lobectomy on the affected side, and postoperatively they continued to have normal blood levels of T3, T4 and TSH. CONCLUSION We report a new phenotype of advanced endemic goiter that affects only one lobe of the thyroid gland, and in the presence of a structurally and functionally normal contralateral lobe.