Endocrine Abstracts

Background: Thyroid-stimulating hormone (TSH) expressing tumors are one of the rarest pituitary adenomas and comprises 0.5–2% of all cases. To our knowledge, only four cases of thyrotropinoma in a pregnant women have been reported up to date.

Case presentation: We present a case of 24-year old women who reported to gynecologist due to secondary amenorrhea and severe headaches. Commissioned laboratory test showed, among others, prolactin 31.0 ng/ml and TSH 3.5 mIU/l. She was referred for magnetic resonance imaging (MRI) of the pituitary gland, where macroadenoma infiltrating the cavernous sinus was found. The octreoscan showed high expression of somatostatin receptors. The patient underwent incomplete transsphenoidal surgery without complications, what resulted in relief of headaches. Immunohistochemical examination revealed expression of TSH and growth hormone (GH), however, the patient did not had any signs of either secondary hyperthyroidism or GH excess. Therefore, the patient was administered somatostatin analogues, thereby obtaining restoration of regular menstruations. Shortly afterwards the patient became pregnant and the pharmacological treatment was discontinued. In the 11th week of pregnancy a severe headache, impaired vision and drooping of eyelid appeared. Urgent MRI proved large progression of the tumor and she was given short-acting octreotide 100 µg three times daily subcutaneously. As a consequence, rapid improvement and withdrawal of symptoms was observed. In the following weeks of pregnancy the treatment was maintained. Patient was regularly monitored, however, remained asymptomatic. At 30th week of pregnancy she was diagnosed with intrahepatic cholestasis and, therefore, the dose of octreotide was reduced to 100 µg per day and the ursodeoxycholic acid was added. Despite this, in the following weeks of pregnancy no clinical signs of tumor were observed. In 38th week of pregnancy the patient gave birth to a healthy daughter weighting 3800 g. After the pregnancy, she returned to long-acting somatostatin analogues and was qualified for the transsphenoidal surgery with subsequent radiotherapy.

Conclusions: Management of pregnant women with pituitary tumors is complex and requires an individual, patient-centered approach. This should include careful monitoring and calculation of both, maternal and fetal risk-benefit ratio. In the described patient, treatment with somatostatin analogues contributed to the reduction of the tumor size, restoration of the normal function of pituitary gland and, above all, successful conception. Moreover, it allowed the avoidance of surgery during pregnancy and achievement of satisfactory disease control so the patient could gave birth full-term.