Primary Thyroid Lymphoma: Clinicopathologic Characteristics and Therapeutic Outcomes of Six Cases in Morocco

Primary non-Hodgkin lymphomas of the thyroid are uncommon and account for 1-5% of all thyroid malignancies and less than 2% of extranodal lymphomas. The aim of the present study was to review our experience and management of primary thyroid lymphoma and to discuss the diagnostic and therapeutic considerations.

All non-Hodgkin lymphoma diagnosed at our institution between 2007 and 2011 were reviewed, six cases of primary thyroid lymphoma were identified. The clinical and pathological features of these patients were analyzed.

There were five females and one male and their mean age was 67.5 years. All patients presented with an enlarging anterior neck mass and two patients also have compressive symptoms. Five patients have a history of pre-existing goiter, four have 'B' symptoms and one was hypothyroid. All patients have B-cell Non Hodgkin Lymphoma. Four patients have stage II disease, while two patients have disseminated disease. All patients underwent thyroid resection. One patient died after surgery. The five others were treated postoperatively with 3-weekly cycles of combination chemotherapy. One patient in stage II received consolidation radiotherapy after chemotherapy. Complete remission was achieved in four patients and one patient had partial response to the treatment. After a median follow-up of 26 months (2-51), three patients are still alive without any relapse, one died and the last was lost to follow up.

Primary thyroid lymphomas are rare. Treatment depends on the histological subtype and stage of the disease, including radiotherapy and chemotherapy. The prognosis usually is favorable with proper treatment.