Sudden onset of facial edema and serum LDH elevation after radiation therapy for malignant lymphoma of the left parotid gland. A case report

A report of a 48 year-old male with non-Hodgkin's lymphoma of the left parotid gland (clinical stage I EA, follicular medium-sized B cell type) is presented. He was solely treated with 30 Gy of radiation to the whole neck region, bilateral paraclavicular region and the left axilla, and 10.6 Gy boost was given to the primary lesion. Five months later, facial edema and serum LDH elevation developed suddenly. Relapse of the malignant lymphoma was suspected, but a whole body CT scan failed to show this. On the contrary, the CT scan showed a diffuse hypoattenuated area of the thyroid gland. In addition to positive antibodies, i.e, antithyroglobulin and antimicrosomal antibodies, total cholesterol and other serum markers also suggested hypofunction of the thyroid due to acute exacerbation of chronic thyroiditis. Immediately after hormone-replacement therapy, his symptoms disappeared and the abnormal serum data improved. Although the relationship between chronic thyroiditis and radiation injury has not been clearly demonstrated, it seems necessary to evaluate thyroid function before radiotherapy for head and neck tumors. Patients with chronic thyroiditis should be followed carefully after radiotherapy. (author)