Gastrointestinal carcinoma first presenting as pituitary mass: recognition of a rare case and multidisciplinary approach for the management of pituitary metastases

Abstract Introduction PMs (pituitary metastases) are rare and only a few cases are reported in the literature. In half of the documented cases, PMs originate from breast and lung cancers, rarely from other sites. They can grow rapidly and present local invasiveness, leading to acute onset of neurological symptoms, such as headache, visual and oculomotor disturbances, or endocrinological signs, such as diabetes insipidus and hypopituitarism. Their rarity and the lack of specific clinical and radiological features often impede their differentiation from other more common sellar area lesions, particularly when history of malignancy is absent. As PMs can be life-threatening, they must be recognized and treated promptly. Management of PMs may also be difficult because the prognosis depends on the course of the primary neoplasm. The case presented below is one of the few documented cases in the world of a pituitary metastasis from a primary gastrointestinal carcinoma. Clinical Case A 76-year-old woman, with no history of malignancy, presented with headache, dizziness and diplopia. Neurologic examination was remarkable for complete left ophthalmoplegia associated with sensitivity deficit in the left half face. Radiologic investigations documented a voluminous sellar and suprasellar formation, with extension in the ipsilateral cavernous sinus, compressing the optic chiasm and ipsilateral temporal lobe. The mass appeared heterogeneous as component of apoplectic infarction. Left cavernous sinus syndrome in apoplectic macroadenoma was diagnosed. Surgical removal of the lesion was performed through a transsphenoidal endoscopic endonasal approach. The histological exam disclosed a metastasis of adenocarcinoma with widespread necrotic-haemorrhagic elements. The immunohistochemical profile suggested an origin from a primary gastrointestinal carcinoma. Hormone replacement therapy and adjuvant therapy were instituted, although radiological investigations failed to identify the site of the primary gastrointestinal carcinoma. Postoperative MRI showed a parasellar residual tumor, which was radiologically stable at 6-month follow-up. The patient will undergo a radiotherapy and neurosurgical evaluation. Conclusions Clinicians should consider the possibility of PMs in patients with symptoms and signs that may suggest the presence of a pituitary mass. Since PMs can be cancer first manifestation, the recognition of PMs determines the referral to adequate oncological therapy. Prognosis is usually poor and it's difficult to estimate as it varies significantly depending on the systemic disease and the primary histology. Recognition and management of PMs remain complex and require a multidisciplinary team of endocrinologists, oncologists, neurosurgeons and neuroradiologists.