SUN-LB86 Case Report: Killian-Jamieson Diverticulum Presenting as a Thyroid Nodule

Introduction: Multitudinous endocrine and non-endocrine disorders cause thyroid nodules, thus in an effort to diagnostically exclude various thyroid malignancies, endocrinologists are obligated to perform a thorough investigative workup. A Killian-Jamieson diverticulum (KJD) is a rare form of cervical esophageal diverticulum that results from anterolateral, mucosal protrusion below the cricopharyngeal muscle. Due to the vicinity of the thyroid gland, this lesion can mistakenly present as a thyroid nodule. Case Description:A 71-year-old female with a past medical history of invasive ductal carcinoma clinical stage 1A, T1a/bN0M0 grade 1 ER+PR+HER2- with treatment composed of radioactive seed localized partial mastectomy and sentinel lymph node biopsy, whole breast radiotherapy, and anastrozole therapy was referred to an endocrinology clinic for evaluation of a left 1.0 cm thyroid nodule incidentally discovered on a CT without contrast scan conducted for bronchitis. Immediate pre-office TSH level collected was normal at 3.28 mIU/L and thyroid ultrasound (US) demonstrated a left lower lobe 2.0 cm AP x 1.7 cm transverse x 2.1cm cephalocaudad heterogenous, solid, well-circumscribed, microcalcified, TI-RADS 4 nodule. In the endocrinology office, the patient’s only symptoms were hoarseness, an improving cough, and neck stiffness. The blood pressure collected was 128/74. Office physical exam demonstrated thyromegaly without nodules. The patient met criteria for a fine-needle aspiration (FNA). A first FNA performed was an uncomplicated biopsy of the lesion, but demonstrated insufficient cellularity on pathology. A second FNA performed was also an uncomplicated biopsy of the lesion, and demonstrated squamous cells, debris material suggestive of vegetable material, and rare benign follicular epithelial cells. Fluoroscopic esophagram was performed subsequently demonstrating a moderate left-sided KJD. Discussion: While literature exists documenting the etiology, pathogenesis, and medical/surgical treatments for KJDs, only a few case reports exist reporting the resemblance KJDs have with thyroid nodules. This case report hopes to illustrate non-endocrinology pathologies that can mimic thyroid nodules while encouraging current healthcare practitioners to recognize the existence of these conditions so that wasteful diagnostic tests or invasive procedures can be avoided.