7965 An Extremely Rapid Progression of Anaplastic Thyroid Carcinoma!

Abstract Disclosure: S. Makadsi: None. T. Altaweel: None. B. Seyoum: None. A. Garg: None. Introduction: Anaplastic Thyroid Carcinoma (ATC) is a very rare and aggressive form of thyroid cancer. It mostly occurs in people over 60 years of age, has unexpected local and distant metastases with short average survival rate of 6 months and approximately 1 in 5 alive after 12 months. Though there are long term survivors, here we are presenting an unfortunate rapid case of a highly aggressive anaplastic thyroid carcinoma. Case Presentation: A 63-year-old female with history of widely metastatic stage IV lung adenocarcinoma diagnosed 3 months prior, alcohol and tobacco abuse, hypertension and arthritis who presented to the hospital with dyspnea and dysphagia. During her hospitalization, she was found to have a large neck mass and hypercalcemia. CT neck showed interval development of a 7.5 cm thyroid mass, with mild narrowing of the airway and bilateral necrotic cervical nodes. A PET/CT a month and a half prior to admission showed no evidence of this mass. Core biopsy of the mass on day 3 of admission showed poorly differentiated thyroid carcinoma, favoring anaplastic histology, stage IVB (T3a N1b M0). The pathology showed variously sized and spaced thyroid follicles with infiltration by highly atypical cells with high mitotic activity, focal prominent nucleoli and hyperchromasia without any specific architectural configuration. On day 6, she underwent tracheostomy placement and was started on chemoradiation with carboplatin and paclitaxel. Additionally, she completed 6 of 20 sessions of radiation to the thyroid. The mass effect on her airway continued to worsen daily. On day 12 of admission, she developed acute hypoxic respiratory failure and shock and was transferred to the ICU. She required aggressive care in the ICU for 3 days and was then transferred back to the medical floor. Subsequently, her clinical status stabilized, however she continued to have a very poor prognosis given the aggressive behavior of the tumor and the airway compromise. Supportive services and primary team had discussion with family regarding the goals of care and the plans were made to transition to comfort measures only. Conclusion: ATC is a rare yet devastating diagnosis. The patient in the discussion demonstrated an ultra-rapid progression of disease. Despite intensive treatment, the patient quickly deteriorated within a month and was placed under hospice care. Currently, treatment options for anaplastic thyroid carcinoma are limited and the prognosis is poor. Investigation into new, fast-acting therapies is necessary to help alter the outcomes in these patients. Presentation: 6/1/2024