Endocrine Abstracts

Prolactinomas are a common type of pituitary tumours, making up about 40% of these tumours in total, with an estimated occurrence of 40-50 people per 100, 000. They are more common in women, especially during their reproductive years, but they can affect anyone at any age. Although most prolactinomas are small and respond well to treatment, around 2-10% are aggressive, growing into nearby areas like the cavernous sinus or sphenoid bone. The World Health Organisation’s 2017 guidelines classify pituitary tumours based on various factors, aiming to improve diagnosis, treatment, and research. However, these guidelines might not always capture the severity of certain tumours, as seen in our case of an aggressive prolactinoma that led to a patient’s death.

Case presentation: We present a 22-year-old male who was admitted with visual bilateral field loss and was found to have a large pituitary lesion with a serum prolactin that is 65000 my/l. A working diagnosis of macroprlactinoma was made and he was treated with an escalated dose of cabergoline, with concomitant replacement of partial anterior pituitary hormone deficiency. After a few months of treatment his tumour had reduced and the vision improved, however, a phase of tumour re-growth took place with complete resistance to dopamine agonist therapy. The tumour invaded the skull base and grew outside his mouth in as short a period as 3 months. Despite efforts for maximum DA dose escalation (reaching 1-2 mg/day) and debulking surgery followed by radiotherapy, his health had deteriorated rapidly and he developed tumour infection and became unfit for chemotherapy options (e.g., temozolamide). He unfortunately succumbed to a cranial infection shortly after that. Although his tumour had not metastasised, it was treatment resistant and locally aggressive, which then led to his death. This case illustrates the need for a more nuanced approach to classifying prolactinomas, especially aggressive ones in young males. It suggests that factors like local tumour invasion should be given more standing in the classification, similar to how other cancers are evaluated (e.g., TNM classification). This could help in better understanding and treating these aggressive tumours.