Patterns of care and treatment outcomes for primary thyroid lymphoma: a single institution study

PURPOSE: The aim of this study was to analyze the patterns of care and treatment outcomes in patients with primary thyroid lymphoma (PTL) in a single institution. MATERIALS AND METHODS: Medical records of 29 patients with PTL treated between April 1994 and February 2012 were retrospectively reviewed. Diagnosis was confirmed by biopsy (n = 17) or thyroidectomy (n = 12). Treatment modality and outcome were analyzed according to lymphoma grade. RESULTS: The median follow-up was 43.2 months (range, 3.8 to 220.8 months). The median age at diagnosis was 57 years (range, 21 to 83 years) and 24 (82.8%) patients were female. Twenty-five (86.2%) patients had PTL with stage IEA and IIEA. There were 8 (27.6%) patients with mucosa-associated lymphoid tissue (MALT) lymphoma and the remaining patients had high-grade lymphoma. Patients were treated with surgery (n = 2), chemotherapy (n = 7), radiotherapy (n = 3) alone, or a combination of these methods (n = 17). Treatment modalities evolved over time and a combination of modalities was preferred, especially for the treatment of high-grade lymphoma in recent years. There was no death or relapse among MALT lymphoma patients. Among high-grade lymphoma patients, 5-year overall survival (OS) and 5-year progression-free survival (PFS) were 75.6% and 73.9%, respectively. Complete remission after initial treatment was the only significant prognostic factor for OS (p = 0.037) and PFS (p = 0.003). CONCLUSION: Patients with PTL showed a favorable outcome, especially with MALT lymphoma. Radiotherapy alone for MALT lymphoma and chemotherapy followed by radiotherapy for high-grade lymphoma can be effective treatment options for PTL.