A Novel Diagnostic Model for Primary Adrenal Lymphoma

ObjectivePrimary adrenal lymphoma (PAL) is easily misdiagnosed as other adrenal masses, such as adrenocortical carcinoma and pheochromocytoma, but patients with PAL benefit little from surgery. The diagnostic method for PAL thus far is limited to adrenal biopsy. In our study, we aimed to develop a quick and efficient diagnostic method for PAL.Methods and ResultsAt the same institution, 505 patients (between 2009 and 2019) and 171 patients (between 2019 and 2020) were separately included in the primary and validation studies. Univariate and multivariate analyses were conducted to evaluate clinical manifestations, laboratory findings, and radiological characteristics. Four determinants (age, bilateral masses, high-density lipoprotein cholesterol, and lactate dehydrogenase) were selected and further incorporated into a regression model to screen PAL. Accordingly, the nomogram was developed for clinical practice. In the primary study, the nomogram showed good discrimination, with an area under the receiver operating characteristic (ROC) curve (AUC) of 95.4% (95% CI, 90.6%–100.0%). Further validation study verified the efficacy of the nomogram, with an AUC of 99.0% (95% CI, 96.9%–100.00%) and 100.0% in all patients and patients with bilateral masses, respectively, and a sensitivity/specificity/positive predictive value (PPV)/negative predictive value (NPV) of 66.67%/99.40%/66.67%/99.40%, 66.67%/100%/100%/92.86%, 50%/99.20%/50%/99.20%, and 100%/100%/100%/100%, in all patients, patients with bilateral adrenal masses, patients with nonfunctional adrenal masses, and patients with positive catecholamine results, respectively. The validation study also revealed a diagnostic specificity of 99.35% and 100% for patients with a unilateral adrenal mass and functional PCC, respectively.ConclusionsThe presented nomogram is the first user-friendly diagnostic model for PAL that simplifies the complex diagnostic process into personalized numeric estimates. We deem that patients who score below 50 are less likely to have PAL. We suggest that clinicians should arrange adrenal biopsy and surgery for patients with nonfunctional tumors and overt catecholamine-secreting tumors, respectively, who receive a score of 50 points or higher to confirm the diagnosis as soon as possible.

Bilateral Adrenal Lymphoma: A Diagnostic Challenge

Bilateral primary adrenal lymphoma is rare with no specific clinical or imaging features. We report herein the case of a 44-year-old man presenting with massive bilateral adrenal tumors associated with normal adrenal function. Computed tomography findings were nonspecific. Because pheochromocytoma was ruled out and the patient had a normal coagulation test, we performed an ultrasound-guided adrenal biopsy for diagnostic purposes. Pathology confirmed adrenal non-Hodgkin's lymphoma. By reporting our case, we aimed to propose a practical approach for this rare entity and to show that there are still situations in which biopsy is necessary to make a diagnosis.

SAT-172 FDG PET/CT in Benign vs. Malignant Adrenocortical Tumors

18F-fluorodeoxyglucose positron emission tomography computed tomography (FDG PET/CT) is frequently used for evaluation of indeterminate adrenal nodules. The objective of this study was to evaluate the diagnostic performance of FDG PET/CT in distinguishing benign adrenocortical adenomas (ACA) from adrenocortical carcinoma (ACC). We identified 139 patients in our institution who completed both FDG PET/CT and adrenal biopsy or adrenalectomy from 2001 to 2019 using the institutional Electronic Medical Record Search Engine (EMERSE). Patients with adrenal pathology revealing non-adrenocortical tumors were excluded. The imaging characteristics of ACAs were compared with ACCs. Sixteen patients with ACAs and 50 patients with ACC were identified; of the latter, 30 were excluded, because FDG PET/CT imaging was completed after adrenalectomy. The average age of the ACC vs. ACA group was 48±14 and 52±17 years, respectively, with a gender composition of 35% and 25% men, respectively. All 20 patients with ACC had FDG avid lesions, defined by imaging report and increased ratio of adrenal tumor maximum standardized uptake value (SUVmax) to hepatic parenchymal average SUV (SUVmean) of greater than 2.5. Among those with ACAs, 11 had positive, 1 had mildly positive, 3 had indeterminate, and 1 had negative FDG PET/CT findings according to the report. Ratio of adrenal SUVmax to hepatic SUVmean was greater in ACC compared to ACA (13.5 versus 1.6, respectively, p = 0.13), but did not reach statistical significance, likely due to the small sample size and unavailability of SUV ratios for all lesions. Our study identified a large number of ACAs that were deemed FDG avid but without adrenal SUVmax to hepatic SUVmean ratio of greater than 2.5. Although the sensitivity, and therefore the negative predictive value, of FDG PET/CT scan is excellent for the diagnosis of ACC, our data does not allow for the calculation of specificity. This is due to the selection bias inherent in our patient population referred for evaluation of unusual adrenal masses, and the fact that ACAs with negative FDG PET/CT often do not undergo surgery or biopsy, and therefore pathology results are not available. Despite this limitation, our findings show that calculation of the ratio of adrenal SUVmax to hepatic SUVmean, rather than lesion SUVmax alone, helps for characterization of adrenal lesions as malignant vs. benign, and that a negative FDG PET/CT is valuable in excluding ACC.

SAT-185 Primary Adrenal Lymphoma Presenting with Symptomatic Hypercalcaemia

Introduction: Primary adrenal lymphoma (PAL) is a rare cause of adrenal enlargement with approximately 200 cases reported in the literature to date. It tends to affect elderly men and has a high incidence of bilateral involvement at diagnosis. We report the case of a 66 year old man, whose PAL manifested with symptomatic hypercalcaemia. A 66 year old male, originally from the Philippines, was referred to the emergency department with nausea, vomiting, weight loss and right flank pain. His past medical history was significant for hypertension, gout and stage 3b chronic kidney disease. His medications were amlodipine, losartan and febuxostat. His family history was significant for hypertension. On examination he was hypertensive (blood pressure, 160/100 mmHg) and hyperpigmented. His laboratory investigations revealed; corrected calcium of 3.79 mmol/l, undetectable PTH, vitamin D 49 nmol/l. He was treated with intravenous (IV) 0.9% saline and IV zoledronic acid and his calcium levels improved. To investigate causes of non-PTH mediated hypercalcaemia, computerised tomography of the thorax, abdomen and pelvis (CT TAP) as well as a positron emission tomography (PET) scan were performed. These demonstrated bilateral, large, metabolically active adrenal masses with no evidence of extra-adrenal disease. Differential diagnosis at this point included bilateral adrenal hyperplasia, metastases, lymphoma or adrenal TB. There were no radiological features of adrenocortical carcinoma (ACC) or phaeochromocytoma and subsequent biochemical investigations confirmed no evidence of cortisol, androgen or catecholamine excess. Adrenocorticotrophic hormone (ACTH) levels were elevated however, and a synacthen test revealed inadequate adrenal reserve (peak cortisol 214 nmol/l). The patient was commenced on maintenance steroids and with stress dose steroid cover, proceeded to adrenal biopsy. Histology confirmed diffuse large B cell non-Hodgkin’s lymphoma. Haematology became involved in his care and he commenced polychemotherapy in the form of R-CHOP, 1 week post confirmation of the diagnosis. His treatment is ongoing and he has tolerated it well with minimal side effects, except a flare of gout. Learning points: PAL should be considered in the differential diagnosis in patients with bilateral adrenal masses. Image guided adrenal biopsy is the gold standard for diagnosis, though caution must be exercised and an ACC or phaeochromocytoma should be excluded prior to biopsy. The prognosis of PAL is poor and therefore early diagnosis and prompt initiation of treatment are required to improve outcomes.

Primary adrenal lymphoma: a case of hiccups

Approximately 250 cases of primary adrenal lymphoma have been reported. We describe an unusual presentation of this condition. Our patient is a 65-year-old male whom presented to the emergency department with 4 days of severe persistent hiccups. He had lost 26 kg in weight in the preceding 4 months. Computed tomography abdomen revealed large invasive bilateral adrenal masses. Biochemical evaluation confirmed adrenal insufficiency. Hiccups resolved within 24 h of steroid replacement. Adrenal biopsy confirmed a diffuse large B-cell lymphoma. Hypotheses for the aetiology of his hiccups include diaphragmatic irritation and primary adrenal insufficiency. This case is interesting for its rarity involving bilateral adrenal glands, Addison’s disease from the primary adrenal tumour and rapid resolution of hiccups with corticosteroid therapy.

Double trouble: two cases of dual adrenal pathologies in one adrenal mass

Summary Context Adrenal incidentalomas (AI) represent an increasingly common problem in modern endocrine practice. The diagnostic approach to AIs can be challenging and occasionally reveals surprising features. Here we describe two rare cases of complex adrenal lesions consisting of phaeochromocytomas with synchronous metastases from extra-adrenal primaries. Case descriptions Patient 1 – a 65-year-old gentleman with a newly diagnosed malignant melanoma was found to harbour an adrenal lesion with suspicious radiographic characteristics. Percutaneous adrenal biopsy was consistent with adrenocortical adenoma. After excision of the skin melanoma and regional lymphatic metastases, he was followed up without imaging. Three years later, he presented with abdominal discomfort and enlargement of his adrenal lesion, associated with high plasma metanephrines. Adrenalectomy revealed a mixed tumour consisting of a large phaeochromocytoma with an embedded melanoma metastasis in its core. Patient 2 – a 63-year-old lady with a history of NF-1-related phaeochromocytoma 20 years ago and previous breast cancer presented with a new adrenal lesion on the contralateral side. Plasma normetanephrine was markedly elevated. Elective adrenalectomy revealed an adrenal tumour consisting of chromaffin cells intermixed with breast carcinoma cells. Conclusions Adrenal incidentalomas require careful evaluation to exclude metastatic disease, especially in the context of a history of previous malignancy. Adrenal biopsy provides limited and potentially misleading information. Phaeochromocytomas are highly vascularised tumours that may function as a sieve, extracting and retaining irregularly shaped cancer cells, thereby yielding adrenal masses with intriguing dual pathology. Learning points: Adrenal incidentalomas require careful evaluation focused on exclusion of underlying hormone excess and malignant pathology. Adrenal biopsy can be misleading and should only be considered in select cases. Phaeochromocytomas harbouring intratumoural metastases from other, extra-adrenal primary malignancies represent rare pathological entities that highlight the complexities that can be presented by adrenal tumours.