Histiocytosis X with thyroid involvement: report of a case.

Histiocytosis X is a disease of histiocyte proliferation in response to some unknown etiology. Thyroid involvement is extremely rare in the literature. In this paper, we present an 18-year-old female with histiocytosis X with thyroid involvement. This patient had had a goiter with normal thyroid function since 12 years of age. A thyroidectomy was done under the suspicion of thyroid cancer. Pathology revealed histiocytosis X. Hypoparathyroidism and hypothyroidism were noted after the operation and were treated with thyroid hormone, vitamin D and calcium carbonate. This patient also had lesions on the left side of mandible, in the suprasellar region and possibly in the right mastoid. A curettage biopsy of her mandibular lesion was also compatible with histiocytosis X. She was proven to have hypothalamic and pituitary dysfunction including hypogonadism and hypoadrenalism. Her thyroid lesion did not recur after the thyroidectomy. The toothache that she had also experienced subsided after the curettage biopsy of the mandibular lesion. Hypothalamic and pituitary dysfunction were controlled by hormone replacement. Because her disease had been running a benign clinical course, no chemotherapy was given.