P1099 - Multi-Focal Pancreatic Solid Lesions: Not Always a Solid Malignancy

Abimbola Adenote, MD, MSc¹, Elit C. Quingalahua, MD², Eric R. Niendorf, MD, PhD¹, Melissa Hart, MD¹, Jorge D. Machicado, MD^1
1Mayo Clinic Health System, Eau Claire, WI; ²Catholic University, Eau Claire, WI

Introduction: Hematologic malignancies are relatively uncommon neoplasms of the pancreas. We hereby present a case in which EUS-FNA of pancreatic masses led to a diagnosis of a hematologic malignancy and prompt therapy of a life threatening complication of the disease.

Case Description/Methods: A 71-year-old woman without remarkable medical history presented with a 2-month history of right rib cage pain, decreased appetite, and weight loss. Initial work-up showed mild anemia (hemoglobin 11.9 g/dL) and acute kidney injury (creatinine 1.24 mg/dL). Otherwise, she had normal blood counts, serum biochemistry, abdominal ultrasound, and EGD with duodenal biopsies. A pan-CT then revealed 3 pancreatic solid masses, 1 right lung nodule, and diffuse bone lesions. Ca 19-9 was normal. EUS revealed 3 large hypoechoic masses in the pancreas (40x33 mm in the head, 21x20 mm in the body, 32x26 mm in the tail) without pancreatic atrophy or ductal dilation. FNA was performed. At 36h of the procedure, she developed lower extremity numbness/weakness and urinary/fecal incontinence. A MRI of the brain and spine demonstrated T6-T10 cord compression due to multiple osseous lesions. Cytology from pancreatic FNA and serum/urine electrophoresis were diagnostic of multiple myeloma (MM). She was treated with emergent radiation therapy of the spine and later with systemic chemotherapy (daratumumab/ bortezomib/ dexamethasone). Her life threatening symptoms improved, but she succumbed 4 months later due to disease progression.

Discussion: Extramedullary involvement of MM more commonly affects the lymph nodes, soft tissue, and upper respiratory tract. Involvement of the pancreas by MM is rare and is present in ~2% of autopsies with MM. There are ~70 cases of pancreatic plasmacytomas reported in literature. In most of these, MM is diagnosed first and subsequently pancreatic involvement is found, typically with a single plasmacytoma. Our case is unusual because three pancreatic plasmacytomas were found at presentation and their identification allowed safer and higher-yield tissue diagnosis with EUS-FNA rather than using bone or lung biopsy. This was critical for timely diagnosis and prompt treatment of cord compression. Our case also highlights the poor prognosis of patients with MM and pancreatic involvement (< 6 months survival), which is shorter than for MM affecting other extramedullary organs. In conclusion, clinicians need to consider pancreatic plasmacytomas in the differential diagnosis of pancreatic masses.



Disclosures:


Abimbola Adenote, MD, MSc¹, Elit C. Quingalahua, MD², Eric R. Niendorf, MD, PhD¹, Melissa Hart, MD¹, Jorge D. Machicado, MD¹. P1099 - Multi-Focal Pancreatic Solid Lesions: Not Always a Solid Malignancy, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.