MON-510 Unmasking A Lymphoma: A Case Of Primary Adrenal Lymphoma Presenting As Adrenal Insufficiency

Abstract Disclosure: S. Ei: None. S.S. Karnik: None. S.S. Kowsika: None. Introduction: Primary adrenal lymphoma, although very rare, is increasingly being recognized as a cause of primary adrenal insufficiency. Primary adrenal lymphoma accounts for less than 1% of non-Hodgkin lymphomas. These lymphomas are aggressive and associated with a poor prognosis. It typically presents as primary adrenal insufficiency, which requires prompt diagnosis and management to prevent life-threatening complications. We discuss a case of primary adrenal insufficiency presenting as adrenal failure in a 78-year-old male patient with an adrenal mass. Case Presentation: A 78-year-old male with a medical history significant for cerebrovascular accident, depression, and cholelithiasis presented with symptoms of lightheadedness, dizziness, weakness, and weight loss, leading to hospitalization. Laboratory tests revealed very low cortisol levels of 0.65 ug/dl (reference range: 6.02-18.40 ug/dl) and elevated ACTH of 205 pg/ml (reference range: 7.2-63.3 pg/ml), indicative of primary adrenal insufficiency. Plasma metanephrine was <25 pg/ml, normetanephrine was 132 pg/ml, serum aldosterone was <1 ug/dl, and DHEA-s was 6.1 ug/dl. Adrenal antibodies were negative. Imaging identified a 4.7 cm left adrenal mass with 37 Hounsfield units, and the right adrenal gland was unremarkable. The patient was started on hydrocortisone 15mg in the morning and 10mg in the evening, along with fludrocortisone 0.1 mg, which led to improvement in energy levels, hypotension, and weight. Although adrenal biopsy was recommended according to guidelines, the patient chose to proceed with adrenalectomy as per urology's recommendation after pre-operative preparation with stress-dose steroids. Pathology revealed diffuse large B-cell lymphoma, prompting further treatment plans, including chemotherapy with R-CHOP. The patient received high-dose steroids prior to chemotherapy to prevent adrenal crisis. Unfortunately, the patient succumbed to his comorbidities and complications of chemotherapy 5 months after the initial diagnosis. Discussion: Primary adrenal insufficiency without 21-hydroxylase antibodies should prompt imaging to evaluate for infiltrating masses. Adrenal insufficiency occurs more commonly in primary adrenal lymphoma compared to other non-lymphomatous metastatic cancers affecting the adrenal glands. This case highlights the complexities of managing primary adrenal insufficiency in the context of concurrent malignancy and emphasizes the need for a multidisciplinary approach involving endocrinology, oncology, and surgery. Presentation: Monday, July 14, 2025