====== Giant pituitary neuroendocrine tumor ====== {{rss>https://pubmed.ncbi.nlm.nih.gov/rss/search/1JMScx_-fBtl7PZRPeEEUPgQ233vKQxB2jz-DB8f6D_BA7gAnW/?limit=15&utm_campaign=pubmed-2&fc=20231014083928}} ---- ---- ===== Epidemiology ===== Giant [[pituitary neuroendocrine tumor]]s comprise about 6-10% of all [[pituitary tumor]]s. It is estimated that 5% of [[pituitary neuroendocrine tumor]] become invasive and may grow to gigantic sizes (>4 cm in diameter). They are mostly clinically non-functioning adenomas and occur predominantly in males ((Iglesias P, Rodríguez Berrocal V, Díez JJ. Giant pituitary neuroendocrine tumor: histological types, clinical features and therapeutic approaches. Endocrine. 2018 Sep;61(3):407-421. doi: 10.1007/s12020-018-1645-x. Epub 2018 Jun 16. Review. PubMed PMID: 29909598. )). ===== Types ===== see also [[Giant somatotroph adenoma]]. ===== Clinical ===== The presenting [[symptom]]s are usually secondary to compression of neighboring structures, but also due to partial or total [[hypopituitarism]]. [[Functioning pituitary neuroendocrine tumor]]s give rise to specific symptoms of hormonal hypersecretion. ===== Treatment ===== The use of [[dopamine agonist]]s is considered a first-line treatment in patients with giant [[macroprolactinoma]]s. [[Somatostatin analog]]s can also be used as primary treatment in cases of [[growth hormone]] and [[thyrotropin]] producing giant adenomas, although remission of the disease is not achieved in the vast majority of these patients. The intrinsic complexity of these tumors requires the use of different therapies in a combined or sequential way. A multimodal approach and a therapeutic strategy involving a multidisciplinary team of expert professionals form the basis of the therapeutic success in these patients ((Iglesias P, Rodríguez Berrocal V, Díez JJ. Giant pituitary neuroendocrine tumor: histological types, clinical features and therapeutic approaches. Endocrine. 2018 Sep;61(3):407-421. doi: 10.1007/s12020-018-1645-x. Epub 2018 Jun 16. Review. PubMed PMID: 29909598. )). ---- The main goal of surgical treatment of giant pituitary neuroendocrine tumor is maximum possible tumor extirpation with minimal side effects, which can be achieved by careful preoperative planning of operative approach, based on directions of tumor extensions and invasiveness. Maximal surgical removal of giant adenomas offers best chances to control tumor growth when followed with adjuvant medical and radiation therapies ((Sinha S, Sharma BS. Giant pituitary neuroendocrine tumors--an enigma revisited. Microsurgical treatment strategies and outcome in a series of 250 patients. Br J Neurosurg. 2010 Feb;24(1):31-9. doi: 10.3109/02688690903370305. PubMed PMID: 20158350. )). ---- While the use of [[endoscopic approach]]es has become increasingly accepted in the resection of [[pituitary neuroendocrine tumor]]s, limited evidence exists regarding the success of this technique for patients with large and giant pituitary neuroendocrine tumors. Major blood supply of giant pituitary neuroendocrine tumors originates from branches of the infraclinoidal portion of the internal carotid artery, different from normal anterior pituitary gland. Surgical route should depend not only on tumor shape and extension but on feeding systems ((Ogawa Y, Sato K, Matsumoto Y, Tominaga T. Evaluation of Fine Feeding System and Angioarchitecture of Giant pituitary neuroendocrine tumor - Implications for Establishment of Surgical Strategy. World Neurosurg. 2015 Oct 5. pii: S1878-8750(15)01255-3. doi: 10.1016/j.wneu.2015.09.087. [Epub ahead of print] PubMed PMID: 26455764.)). The main goal of surgical treatment of giant pituitary neuroendocrine tumor is maximum possible tumor extirpation with minimal side effects, which can be achieved by careful preoperative planning of operative approach, based on directions of tumor extensions and invasiveness. Maximal surgical removal of giant adenomas offers best chances to control tumor growth when followed with adjuvant medical and radiation therapies ((Sinha S, Sharma BS. Giant pituitary neuroendocrine tumors--an enigma revisited. Microsurgical treatment strategies and outcome in a series of 250 patients. Br J Neurosurg. 2010 Feb;24(1):31-9. doi: 10.3109/02688690903370305. PubMed PMID: 20158350.)). ---- In cases of progressive enlargement of residual lesions, a second endoscopic debulking of the tumor may be considered for control of the disease ((Gondim JA, Almeida JP, Albuquerque LA, Gomes EF, Schops M. Giant pituitary adenomas: surgical outcomes of 50 cases operated on by the endonasal endoscopic approach. World Neurosurg. 2014 Jul-Aug;82(1-2):e281-90. doi: 10.1016/j.wneu.2013.08.028. Epub 2013 Aug 29. PubMed PMID: 23994073. )). ===== Outcome ===== Giant pituitary neuroendocrine tumors carry higher surgical risks despite recent advances in microsurgical and/or endoscopic surgery, and postoperative acute catastrophic changes without major vessel disturbance are still extremely difficult to predict, may manifest as postoperative pituitary apoplexy, and are associated with very poor outcomes. Resection of both large and giant pituitary neuroendocrine tumors by microscopic [[transsphenoidal]] surgery may be safe and effective surgical technique with low morbidity and mortality ((Karki M, Sun J, Yadav CP, Zhao B. Large and giant pituitary neuroendocrine tumor resection by microscopic trans-sphenoidal surgery: Surgical outcomes and complications in 123 consecutive patients. J Clin Neurosci. 2017 Aug 1. pii: S0967-5868(16)30922-5. doi: 10.1016/j.jocn.2017.07.015. [Epub ahead of print] PubMed PMID: 28778803. )). ===== Case series ===== [[Giant pituitary neuroendocrine tumor case series]]. ===== Case reports ===== A 21-year old male, who required urgent surgery because of progressive visual disturbance due to giant pituitary neuroendocrine tumor. On brain MRI with contrast, it was revealed an extra-axial tumor extending anteriorly over planum sphenoidal with the greatest diameter was 5.34 cm. A transcranial approach was chosen to resect the tumor. Near-total removal of the tumor was achieved without damaging the vital neurovascular structure. The visual acuity was improved and no significant postoperative complication. Pathology examination revealed pituitary neuroendocrine tumor. Transcranial surgery for pituitary neuroendocrine tumor is still an armamentarium in neurosurgical practice, especially in the [[COVID-19 pandemic]] to provide a safer surgical approach ((Golden N, Niryana W, Awyono S, Eka Mardhika P, Bhuwana Putra M, Stefanus Biondi M. Transcranial approach as surgical treatment for giant pituitary neuroendocrine tumor during COVID 19 pandemic - What can we learn?: A case report. Interdiscip Neurosurg. 2021 Feb 25:101153. doi: 10.1016/j.inat.2021.101153. Epub ahead of print. PMID: 33654658; PMCID: PMC7906516.)). ===== References =====