MON-415 Pituitary Carcinoma With Sequential Hormone Hypersecretion And A Novel Renal Complication Of Hormone Excess

• Published in: Journal of the Endocrine Society 2019-04, Vol.3 (Supplement_1)
• Main Authors: Devine, Kerri, Lewis, Joanne, Fielding, Richard, Hill, John, Haugk, Beate, Johnson, Sarah, James, Andy
• Format: Article
• Language: English
• Subjects: Neuroendocrinology and Pituitary
• ISSN: 2472-1972; 2472-1972
• DOI: 10.1210/js.2019-MON-415

Background: Pituitary carcinoma is a rare diagnosis, occurring in 100 ug/L, IGF-1 97 nmol/L). The tumour remnant had expanded into the cavernous sinus on MRI. Biopsy of the lesion showed a tumour with strong PRL staining, micro-vacuolation, sparse GH staining and Ki-67 of 15-20% suggesting an aggressive nature and potentially in keeping with the rare acidophilic stem cell tumour subtype. He underwent stereotactic pituitary radiotherapy and later commenced pegvisomant therapy after a failed octreotide trial. Following this, prolactin levels continued to rise. Unfortunately, subsequent investigations for back pain with bilateral hand paraesthesia (at first considered secondary to acromegaly) revealed metastatic lesions in spine, lung and stomach - the latter confirmed to be of PRL-secreting neuroendocrine origin on biopsy. There was no uptake on octreotide scan. In response to new renal dysfunction (creatinine 463 umol/L with microscopic haematuria and proteinuria), a renal biopsy was also performed and revealed changes compatible with interstitial nephritis with cast nephropathy. The tubular casts stained positive for PRL, and serum PRL at this time reached a peak of 3.7 million mIU/L. Temolozamide has been commenced,