ESA-SRB-AOTA 2019

Pituitary Lymphoma – a rare case of hypopituitarism. (#608)

Albert Kim 1 2 , David R Chipps 1 2
  1. Department of Diabetes and Endocrinology, Westmead Hospital, Westmead, NSW, Australia
  2. Faculty of Medicine & Health, University of Sydney, NSW 2600, Australia

Case

60-year-old Caucasian man presented with an acute, unilateral third nerve palsy in the context of functional decline over 8 weeks. Imaging revealed a pituitary mass with parasellar extension into the cavernous sinus. Bloods revealed panhypopituitarism– TSH 0.54mIU/L(RR 0.4-4.0), T4 8.2pmol/L(RR 9.0-19.0), T3 2.1pmol/L(RR2.6-6.0),  ACTH 2.4pmol/L(RR0-12), cortisol 198nmol/L(RR100-540), IGF-1 3.0nmol/L(RR6.3-28.1), FSH 4.7IU/L(RR<9.0), LH 2.4IU/L(RR<9.0), total testosterone 3.5nmol/L(RR>10) and prolactin 868mIU/L(RR<400).

Hydrocortisone, thyroxine and testosterone was commenced. Inflammatory markers were elevated, and blood counts revealed anaemia and leukopaenia. Investigations for vasculitis, tuberculosis, sarcoidosis and syphilis were negative. Pituitary biopsy was planned though not performed as FDG-PET revealed numerous avid lesions throughout the liver, spleen, skeleton and intra-abdominal lymph nodes. Liver lesion biopsy confirmed the diagnosis of diffuse large B-cell lymphoma and chemotherapy was commenced with resolution of the third nerve palsy, as well as radiological remission of disseminated disease. He remains on hydrocortisone and thyroxine replacement currently and is continuing to receive chemotherapy.

Discussion

Systemic malignancies infrequently metastasise to the pituitary with an estimated incidence of 5.1%. The incidence of systemic lymphoma involving the pituitary is very rare with lymphomas accounting for 0.5% of tumour metastases to the pituitary.(1)

Pituitary metastases represent an uncommon complication of systemic malignancy. Most commonly, these patients present with diabetes insipidus(45.2%of pituitary metastases), highlighting the predominance of metastasis to the posterior pituitary via direct arterial supply. Pituitary metastases may present atypically with anterior pituitary insufficiency(23.6%) or ophthalmoplegia(21.6%). Constitutional symptoms are less common but should raise concern for atypical aetiology.

Anterior pituitary involvement is more frequently seen in pituitary lymphoma compared to solid organ tumours.(2) Pituitary function may recover with chemotherapy for the underlying lymphoma.(3, 4)

Conclusion

Our case highlights the importance of considering a broad range of differential diagnosis in the investigation and management of hypopituitarism. The absence of diabetes insipidus does not exclude pituitary metastases.

  1. Komninos J, Vlassopoulou V, Protopapa D, Korfias S, Kontogeorgos G, Sakas DE, et al. Tumors metastatic to the pituitary gland: case report and literature review. The Journal of Clinical Endocrinology & Metabolism. 2004;89(2):574-80.
  2. Ogilvie CM, Payne S, Evanson J, Lister TA, Grossman AB. Lymphoma metastasizing to the pituitary: an unusual presentation of a treatable disease. Pituitary. 2005;8(2):139-46.
  3. Nakashima Y, Shiratsuchi M, Abe I, Matsuda Y, Miyata N, Ohno H, et al. Pituitary and adrenal involvement in diffuse large B-cell lymphoma, with recovery of their function after chemotherapy. BMC endocrine disorders. 2013;13(1):45.
  4. Kenchaiah M, Hyer SL. Diffuse large B-cell non Hodgkin's lymphoma in a 65-year-old woman presenting with hypopituitarism and recovering after chemotherapy: a case report. Journal of medical case reports. 2011;5(1):498.