Manifestation of primary hyperthyroidism after pituitary adenomectomy: a case report

[Manifestation of Graves' disease, resulting from radiosurgical treatment of acromegaly, in a patient with panhypopituitarism]

Cases of thyrotoxicosis associated with a previous case of secondary hypothyroidism are extremely rare. This article presents a rare clinical case of Graves' disease manifestation in a patient with secondary hypothyroidism after radiosurgical treatment of acromegaly. A 38-year old woman presented with acromegaly and endo-supra-laterosellar pituitary adenoma. After non-radical removal of the pituitary adenoma, radiosurgical treatment of the of the residual tissue of the pituitary tumor in the cavernous sinus area was performed. After 14 months of radiation therapy, the acromegaly was in remission; after 24 months of radiation therapy, panhypopituitarism developed (secondary hypothyroidism, adrenal insufficiency, hypogonadism, and growth hormone deficiency). Furthermore, 1.5 years after the panhypopituitarism was diagnosed, the manifestation of Graves' disease was also noted, requiring thyrostatic and radioactive iodine treatments. Diagnostic criteria for secondary hypothyroidism are low levels of the thyroid hormones free T4 and free T3, with a reduced, normal or slightly elevated level of thyroid stimulating hormone (TSH). The criterion for the development of thyrotoxicosis in the context of the secondary hypothyroidism was the persistent increase in the level of free T4 despite adequate drug therapy with levothyroxine. In the case report, the patient's diagnosis of Graves' disease was confirmed by the presence of a high level of antibodies to the TSH receptor.

Prolactin-Producing Pituitary Carcinoma, Hypopituitarism, and Graves' Disease-Report of a Challenging Case and Literature Review

INTRODUCTION

The diagnosis of pituitary carcinoma is very rare, requires the evidence of metastatic disease, and has a poor overall survival. Malignant prolactinoma frequently requires dopamine agonist therapy, pituitary surgery, radiotherapy, and even chemotherapy.

CASE DESCRIPTION

A 19-year-old female presented with galactorrhea, primary amenorrhea, and left hemianopsia. Complementary study detected hyperprolactinemia and a pituitary macroadenoma with cavernous sinus invasion and suprasellar growth. She was treated with cabergoline and bromocriptine without clinical or analytical improvement. Resection of the pituitary lesion was programmed and a non-contiguous lesion of the nasal mucosa was detected during the approach. This metastasis led to the diagnosis of prolactin-producing pituitary carcinoma. After partial resection, the patient was submitted to radiotherapy for residual disease with persistent symptoms. She developed growth hormone deficiency, central hypothyroidism, hypogonadism, and permanent diabetes insipidus. Six years later she was admitted for the suspicion of secondary adrenal insufficiency and thyrotoxicosis. Physical findings, laboratory data, thyroid ultrasound, and scintigraphy achieved the diagnosis of Graves' disease and hypocortisolism. She was treated with hydrocortisone and methimazole, but central hypothyroidism recurred after antithyroid drug withdrawal. Nine years after the diagnosis of a pituitary carcinoma, she maintains treatment with bromocriptine, has a locally stable disease, with no metastases.

CONCLUSION

This report highlights an unusual presentation of a prolactin-producing pituitary carcinoma in a young female. The patient had multiple hormone deficiencies due to a pituitary lesion and treatments. The posterior development of hyperthyroidism and adrenal insufficiency brought an additional difficulty to the approach.