Malignant lymphoma of the thyroid gland.

Malignant lymphoma of the thyroid gland is a rare entity; only 200 cases have been reported to date since 1960. Four patients with this disease presented at the Kingston clinic of the Ontario Cancer Treatment and Research Foundation. Those with localized malignant lymphoma, particularly the histiocytic types, responded favourably to resection of as much of the tumour as possible and subsequent local radiation with cobalt-60 telecurietherapy (3000 to 4000 rads in 3 to 4 weeks). The results of local radiation alone after a biopsy in patients with inoperable localized diseases are encouraging; it is possible, but not yet established, that some of these patients are cured. It has been suggested that the tumour is dependent on thyroid-stimulating hormone but conclusive evidence is not yet available.