TY - JOUR T1 - Poorly Differentiated Thyroid Carcinoma: Single Institution Series of Outcomes JF - Anticancer Research JO - Anticancer Res SP - 2531 LP - 2539 DO - 10.21873/anticanres.15731 VL - 42 IS - 5 AU - SIDDHARTH KUNTE AU - JONATHAN SHARETT AU - WEI WEI AU - CHRISTIAN NASR AU - BRANDON PRENDES AU - ERIC LAMARRE AU - JAMIE KU AU - ROBERT R. LORENZ AU - JOSEPH SCHARPF AU - BRIAN B. BURKEY AU - AKEESHA SHAH AU - NIKHIL JOSHI AU - JESSICA L. GEIGER Y1 - 2022/05/01 UR - http://ar.iiarjournals.org/content/42/5/2531.abstract N2 - Background and Aim: Poorly differentiated thyroid cancer (PDTC) is a rare but aggressive subtype of thyroid cancer that portends a poor prognosis. There remains a paucity of literature on PDTC outcomes. The aim of our study was to evaluate outcomes of PDTC in our tertiary care facility. Patients and Methods: We identified all histologically confirmed PDTC cases from 1997-2018 treated at our Institution and collected data points in an IRB-approved registry. We then conducted a retrospective study to assess outcomes and identified factors associated with inferior outcomes. Results: Twenty-three patients were identified with a median age at diagnosis of 60 years (range=39-89 years). Nineteen (83%) underwent total thyroidectomy. Eight (42%) patients had lymph node dissections and 2 (11%) underwent adjuvant radiation. Thirteen (68%) patients were treated with radioactive iodine (RAI). Those who underwent total thyroidectomy had a median overall survival (mOS) of 88 months, 5 year-OS of 56%, 5 year-local recurrence-free survival (LRFS) of 45%, and 5 year-distant recurrence-free survival (DRFS) of 36%. T4 disease had worse mOS (14 vs. 87 m, p=0.0082), and 5 year-LRFS rate (12 vs. 74%, p=0.0312) compared to T1-3. N0 disease had an improved mOS (172 vs. 32 m, p=0.0013), 5 year-LRFS rate (63 vs. 17%, p=0.0033), and 5 year-DRFS (57 vs. 0%, p=0.0252). Eight out of 23 patients (35%) were alive at last follow-up, with a median of 68 months (range=20-214). The most common cause of death was distant recurrence (73%). Six patients received systemic therapy with various tyrosine kinase inhibitors with a median duration on treatment of 7 months (range=1-30 months). Conclusion: Advanced T and N stage were factors associated with significantly inferior outcomes. While select patients benefited with systemic treatment, it remains unclear if intensified locoregional therapy should be considered in patients with PDTC. ER -