A Unique Presentation of a Paraganglioma and Its Consequences

Abstract

Introduction: Paragangliomas (PGL) are extremely rare tumors arising from extra-adrenal neural crest cells with an incidence of 0.8 per 100,000 person-years. Sympathetic chain PGLs usually arise in the abdomen, with about 75% of them arising intra-abdominally [2]. On CT or MRI, PGLs are usually have homogenous enhancement or central areas of low attenuation. The consequences of PGLs are many, and one complication that is rarely noted is glycemic disturbances with catecholamine excess. Here, we present a case of a radiographically unique appearing PGL that resulted in dramatic improvement of diabetes after resection.Case: 41 year old male with a past medical history of diabetes, CKD and developmental delay presented with hyperglycemia. Patient’s home regimen of Glargine 15 units qHS and Humalog 5 units TID AC had run out a few days prior. Patient had Hemoglobin A1c of 11.8% mg/dL and a C-peptide of 0.4 ng/ml. Endocrine was initially consulted for glucose management. Hospital course was complicated by abdominal pain and CT imaging showed low attenuation splenic masses, retroperitoneal lymphadenopathy and a large, necrotic appearing mesenteric mass consistent with lymphoma. MRI reaffirmed mass with peripheral enhancement and central necrosis consistent with neoplasm.Patient underwent biopsy of lymphadenopathy, which came back benign and then went for biopsy of mass. As the needle entered the mass, the patient became acutely hypertensive and tachycardic. He received phentolamine with good response and labs were drawn for catecholamine producing tumor. Plasma norepinephrine level was 6048 pg/ml and a chromogranin level of 4788 ng/ml. An MIBG scan revealed focal uptake at the lesion without evidence of metastasis. In the subsequent weeks, he was alpha- and then beta-blocked and underwent resection of mass that was complicated by transient hypotension and hypoglycemia. Eventually, patient’s blood pressure was controlled and insulin requirements dropped precipitously to just requiring 4 units of glargine by discharge.Discussion: This patient had a mass on CT scan that appeared to be consistent with lymphoma as opposed to PGL that led to biopsy and subsequent catecholamine crisis. Fortunately, this was controlled and subsequent resection led to improvement in the patient’s glycemic control. It has been thought that glucose intolerance in PGL patients is due to impaired insulin release through desensitization of the beta-adrenergic receptor. Furthermore, Catecholamines, as counter-regulatory hormones, have been well documented to raise blood sugar on this basis as well. Fortunately for our patient, he survived an initial biopsy and post-operatively, was able to actually have an improvement in his glycemic control. It also is a reminder to always do a screen for PGL before doing a needle biopsy of a compatible abdominal mass.