Endocrine Abstracts

JOINT3371

Introduction: Metastatic PitNET (mPitNET) is extremely rare endocrine neoplasm, defined by the presence of craniospinal and/or systemic metastases, accounting for less than 0.2% of all pituitary tumors. Its low incidence makes both diagnosis and treatment challenging. The prognosis is generally poor, with an estimated 5-year survival rate as low as 35%. Symptoms of mPitNET are often a mixture of effects of hormonal activity, local invasiveness and distant metastasis. Surgery remains the first-line treatment - more than 80% of mPitNET cases require at least two surgeries, while more than 25% require at least four. However, depending on the individual case, additional therapeutic options may include radiotherapy, somatostatin analogs, dopamine agonists, and temozolomide (TMZ). It has been observed that patients receiving TMZ are more likely to achieve 5-year survival compared to those on alternative treatment regimens that do not include TMZ. However, since mPitNET remains a clinical challenge and frequently do not respond to first-line treatment, other therapeutic options, such as peptide receptor radionuclide therapy, immune checkpoint inhibitors, and tyrosine kinase inhibitors, have been tried.

Case Presentation: A 15-year-old, Caucasian male patient, was referred to endocrinology department due to gynecomastia, recurrent headaches, and visual disturbances. Laboratory tests did not reveal any abnormalities, while MRI revealed a large sellar mass suggestive of craniopharyngioma. The lesion was surgically removed, and histopathological examination identified a chromophobe pituitary adenoma with low ACTH expression (5% of cells). The clinical course of disease was aggressive, with numerous recurrences and mass effect. The patient had a total of seven debulking surgeries, complicated by infections (Acinetobacter baumannii) and acute hydrocephalus. Adjuvant stereotactic radiotherapy was delivered. Seven years after diagnosis, metastases were detected in the cerebellopontine angle, frontal lobe, and anterior vagal trunk. Scintigraphy showed expression of somatostatin receptors and lanreotide therapy was introduced for treatment. The patient subsequently received TMZ resulting in partial tumor regression and disease stabilization, however, severe side effects (myelosuppression, gastrointestinal symptoms) were observed. After twenty years of treatment, the patient remains clinically stable but struggles with visual impairment, epilepsy, and hypopituitarism. Current treatment includes lanreotide, antiepileptic drugs and thyroxine and hydrocortisone replacement.

Conclusion: By presenting this case, we wish to emphasize how advancements in diagnostic and therapeutic techniques, we can prolong patient’s life - even in the disease with such a poor prognosis.