Management of a pregnant woman with thyrotropinoma: a case report and review of the literature

Thyrotropinoma with silent somatotroph and lactotroph adenoma during pregnancy

Summary

Thyrotropinomas are an uncommon cause of hyperthyroidism and are exceedingly rarely identified during pregnancy, with limited evidence to guide management. Most commonly they present as macroadenomas and may cause symptoms of mass effect including headache, visual field defects and hypopituitarism. We present a case of a 35-year-old woman investigated for headaches in whom a 13 mm thyrotropinoma was found. In the lead-up to planned trans-sphenoidal surgery (TSS), she spontaneously conceived and surgery was deferred, as was pharmacotherapy, at her request. The patient was closely monitored through her pregnancy by a multi-disciplinary team and delivered without complication. Pituitary surgery was performed 6 months post-partum. Isolated secondary hypothyroidism was diagnosed postoperatively and replacement thyroxine was commenced. Histopathology showed a double lesion with predominant pituitary transcription factor-1 positive, steroidogenic factor negative plurihormonal adenoma and co-existent mixed thyroid-stimulating hormone, growth hormone, lactotroph and follicle-stimulating hormone staining with a Ki-67 of 1%. This case demonstrates a conservative approach to thyrotropinoma in pregnancy with a successful outcome. This highlights the need to consider the timing of intervention with careful consideration of risks to mother and fetus.

Learning points

Thyrotropinomas are a rare cause of secondary hyperthyroidism. Patients may present with hyperthyroidism or symptoms of mass effect, including headaches or visual disturbance. Thyrotropinoma in pregnancy presents a number of pituitary-related risks including pituitary apoplexy and compression of local structures. Hyperthyroidism in pregnancy raises the risk of complications including spontaneous abortion, preeclampsia, low birthweight and premature labour. Timing of medical and surgical therapies must be carefully considered. A conservative approach requires careful monitoring in case emergent intervention is required.

Fertility issues in aggressive pituitary tumors

The management of aggressive pituitary adenomas represents a special clinical challenge, and usually involves a combination of surgery, radiotherapy and pharmacological agents to control tumor growth and hormone abnormalities. Fertility is commonly affected in these patients due to compressive effects of the tumor, pituitary hormone dysfunction or as a result of the multiple therapies. The initial approach to restore fertility involves the reduction of tumor volume by the use of dopamine agonists in prolactinomas and by surgery in other pituitary adenomas. Somatostatin analogues are alternative options for GH, ACTH and TSH-secreting tumors. When present, pituitary deficiencies should be appropriately treated, particularly GH deficiency that has been associated with poor pregnancy rates in hypopituitary patients. Other therapies for aggressive pituitary tumors, such as invasive surgery, radiotherapy and temozolamide, may lead to infertility. In such cases, fertility preservation strategies might be considered and discussed with the patient desiring conception before or during treatment. In men and women with hypogonadotropic hypogonadism, administration of gonadotropins or pulse GnRH has resulted in satisfactory pregnancy rates. If spontaneous gestation is not achieved, assisted reproduction techniques can be employed as the last line of treatment. In any context, pre-conception counseling and care are essential as pregnancies in women with aggressive pituitary tumors should always be considered high risk.

Surgical indications for pituitary tumors during pregnancy: a literature review

PURPOSE

Surgical indications for pituitary tumors during pregnancy are rare, and are derived from a balance between expected benefits, particularly for maternal benefits, and anesthetic/surgical risks.

METHODS

A literature review was performed to define the optimal surgical indications for pituitary adenomas (PA) and other pituitary tumors during pregnancy.

RESULTS

Main benefits are expected in case of critical visual impairment and/or life-threatening endocrine disturbances. Multidisciplinary patient management is systematically required although nonobstetric surgery presents a reasonable risk during pregnancy. The risks of congenital malformation during the first trimester and those of premature birth during the third trimester make the second trimester the optimal period for surgery. In prolactin-secreting, nonsecreting, GH- and TSH-secreting PAs, transsphenoidal surgery (TS) is recommended in cases involving severe visual impairment, characterized by severe visual field deficit, visual acuity impairment, and abnormal optical coherence tomography findings, and when no other medical alternatives are possible and/or sufficient. Uncontrolled and severe Cushing's disease (CD) during pregnancy increases both maternal and fetal morbimortality, thus justifying TS or sometimes dopamine agonist therapy as a safer alternative. Finally, metyrapone, ketoconazole, or bilateral adrenalectomy could be recommended in certain cases after the failure of medical therapies and/or TS. Surgery is also required for suprasellar meningiomas, craniopharyngiomas, and pituitary cysts in the case of severe visual deficit.

CONCLUSION

Surgical indications for pituitary tumors are rare during pregnancy; therefore, surgery should be avoided when possible. Further, the second trimester should be considered as the optimal surgical period. Severe visual disturbance and uncontrolled CD are the main surgical indications during pregnancy.

Pituitary Tumors in Pregnancy

Pituitary adenomas are common. The impact of pituitary tumors on fertility are mainly caused by oversecretion and/or undersecretion of pituitary hormones or compression of pituitary stalk and normal pituitary tissue by the tumor. Diagnosing and managing pituitary tumors during pregnancy involve many challenges, including the effect of hormone excess or deficiency on pregnancy outcome, changes in the pituitary or pituitary-related hormones, changes in tumor size, and the impact of various treatments of pituitary tumors on maternal and fetal outcomes. This article discusses the diagnosis and treatment of patients with prolactinomas, acromegaly, Cushing disease, and other pituitary tumors during pregnancy.