6671 A Recurrent Mass After Thyroid Cancer Treatment

Abstract Disclosure: N. Sekhon: None. K.Z. Win: None. Background: Differentiated thyroid cancers have an excellent prognosis if completely resected and their recurrence rate varies depending on the nature and type of the thyroid tumor. We report a case of symptomatic recurrent mass 1.5 years after hemithyroidectomy for a small locally invasive follicular thyroid cancer. The recurrent mass mimicked malignancy on ultrasound but was pathologically determined to be a suture granuloma. Case: A 62-year-old male with history of follicular thyroid cancer s/p left thyroidectomy presented with a symptomatic neck mass, dysphagia, voice change, and worsening snoring. Thyroid tumor pathology was reported as follicular carcinoma pT1bpNX, 1.4 cm in size, clear margins, no vascular invasion with one focus of transcapsular invasion. He had normal surveillance investigations including thyroglobulin and thyroid ultrasound. He had a normal esophagogastroduodenoscopy which was performed for dysphagia and choking. The thyroid ultrasound showed an indeterminate solid heterogeneous and hypoechoic ovoid soft tissue node measuring 6 mm x 3 mm x 5 mm just right of midline and a 4 mm left neck hypoechoic nodule with no central fatty hilus located lateral to the jugular vein. The lymph node morphology was not typically benign and the patient underwent fine needle aspirate of the mass suggestive of a benign mass. This was followed by surgical removal of the mass and pathologic identification of a suture granuloma. There was resolution of dysphagia after removal of the mass. Discussion: Thyroid tumor recurrence rate is about 15% and is usually seen in aggressive forms or in incomplete resections due to the unrecognized extent of the tumor. Recurrences can be local, regional or distant. Suture granuloma is a rare complication after thyroidectomy and reflects an inflammatory response to retained foreign material. It develops slowly after the thyroidectomy and presents as a painless mass mimicking malignancy or lymph node metastasis. Other lesions that can mimic thyroid cancer on ultrasonography include chronic granulomatous lesions, traumatic neuroma and surgical clip. Conclusion: Our case highlights that suture granuloma should be considered in addition to malignant recurrence in cases of painless mass at the site of thyroidectomy. References: 1. Javalgi AP, Arakeri SU. Post thyroidectomy suture granuloma: a cytological diagnosis. J Clin Diagn Res. 2013 Apr;7(4):715-7. 2. Kristen Kobaly, Susan J. Mandel, Jill E. Langer, Clinical Review: Thyroid Cancer Mimics on Surveillance Neck Sonography, The Journal of Clinical Endocrinology & Metabolism, Volume 100, Issue 2, 1 February 2015, Pages 371-375 3. Ryan Alghanemi, Thomas Steinmüller, Abrupt onset of suture granuloma 27 years after hemithyroidectomy, Journal of Surgical Case Reports, Volume 2023, Issue 6, June 2023, rjad284. Presentation: 6/2/2024