AB064. Two case reports & review of literature: perioperative surgical management of symptomatic large non-functioning pituitary masses in early pregnancy.

Background: Pituitary masses during pregnancy pose many challenges, requiring inputs from multidisciplinary teams. Where surgery is required, such as in cases of impending pituitary apoplexy, timing must be carefully selected. Several case reports have suggested good outcome with surgery in later trimesters or postpartum. However, insufficient data exists on surgical strategies for such patients with severe visual symptoms in early pregnancy. We report two patients with pituitary masses requiring surgical excision.

Methods: Review of patients' notes and imaging, with literature review.

Results: A 35-year-old gravida 2 para 1 female at 9 weeks gestational age (GA) presented with chronic bitemporal hemianopia, with acute left eye blurring of vision, identified during a pre-employment screening test. Imaging revealed a 38 mm × 29 mm × 33 mm sellar mass with compression onto the optic chiasm. She had no significant hormonal imbalances other than hyperprolactinemia and newly diagnosed Hashimoto's thyroiditis. She underwent transsphenoidal resection, with histology showing pituitary adenoma with blood clots. Similarly, our second patient was a 37-year-old gravida 4 para 2 female at 12 weeks GA with worsening bitemporal hemianopia with a 25 mm × 21 mm × 18 mm sellar mass displacing and compressing the optic chiasm. After resection she had marked objective improvement in her vision, but developed diabetes insipidus, and final histology revealed pituicytoma. Preoperative considerations for timing of surgery include pituitary apoplexy or acutely worsening visual field deficit. The pituitary physiologically increases in size during pregnancy, which can compress the optic chiasm and worsen visual deficit. In the case of apoplexy, delayed identification can have devastating consequences. However, major surgery in the first trimester may increase spontaneous miscarriage. The effects of imaging investigations from radiation, or gadolinium contrast administration, are also uncertain. While surgical positioning remains unaffected, other intraoperative considerations include strictly avoiding hypotension and using pregnancy-safe agents. Postoperative considerations include correcting hormonal deficiencies of hypopituitarism, including acute central hypocortisolism, diabetes insipidus and interruption of gonadotrophin production which could negatively affect pregnancy. Fetal heart rate must also be assessed.

Conclusions: Determining timing of surgery to ensure well-being of both mother and fetus involves a difficult balance of risks. In our two cases, a thorough discussion with multidisciplinary input was required to achieve good outcomes.