Lymphoma of the thyroid. Report of five cases and review

Thyroid lymphoma is a rare disease seen most commonly in elderly women and associated with Hashimoto's thyroiditis. Five cases of thyroid lymphoma seen and treated at Hahnemann University Hospital between 1979 and 1988 are retrospectively reviewed. All patients underwent a staging workup, including chest radiograph, intravenous pyelography, abdominal/pelvic computed tomogram (CT) scan and/or lymphangiogram, and bone marrow. An extensive review of the literature is presented. Risk factors for thyroid lymphoma are discussed, enabling the clinician to differentiate thyroid lymphoma from thyroid carcinoma. Thyroidectomy may be indicated in a small number of cases, provided that the patient has disease localized within the thyroid such that total gross resection can be achieved. It is proposed that patients with bad prognostic factors may benefit from the administration of chemotherapy initially before or after radiotherapy rather than using chemotherapy as salvage therapy. Irradiating the patient to the neck and mediastinum to 40 Gy, in 4-5 weeks, is recommended, except possibly for tumor that is extremely well localized in the neck. Finally, the necessity of a full staging work-up, including lymphangiogram and/or abdominal/pelvic CT is emphasized.