P3215 - MGUS and the Mystery Mass: Unearthing Extramedullary Hematopoiesis With EUS Biopsy!

Christin Wilkinson, MD¹, MaryKate Kratzer, MD², Karissa Lambert, MD³, Stephanie Ibarra Lepe, MD², Abdulazeez Swaiti, MD¹, Jinye Liu, DO², Christina Santana, MD², Amy Chang, MD², Saeed Graham, MD¹, Matthew Tugman, BA⁴, Michelle Cooley, BS⁴, Catherine Gray, BS⁴, Zarak Khan, MD³, Hassam Ali, MD¹, Rahul Pamarthy, MD¹, Prashant Mudireddy, MD^3
1East Carolina University, Greenville, NC; ²East Carolina University Medical Center, Greenville, NC; ³East Carolina Gastroenterology, Greenville, NC; ⁴East Carolina University Brody School of Medicine, Greenville, NC

Introduction: Extramedullary hematopoiesis is blood cell production at a site other than the bone marrow. It most commonly occurs in the liver, spleen, or lymph nodes. Other sites have been identified but are much rarer. It is associated with hematologic conditions such as myeloproliferative disorders, leukemia, and hemolytic anemia, among others. Diagnosis can be achieved through fine needle aspiration.

Case Description/Methods: An 85-year-old female with a PMHx of IgG lambda MGUS diagnosed in 2011, urethral cancer s/p XRT in 2010, appendicitis s/p laparoscopic appendectomy complicated by SBO with ex-lap without bowel resection with residual ventral hernia, presented for post remission CT scan A/P that showed a mixed attenuating mass in the upper anterior abdominal wall suspicious for sarcoma with possible indolent growth. A year later, follow up CT scan showed the multilobulated soft tissue intraabdominal mass increased in size to 7.2 x 6.3 cm from 6.5 x 6.7 cm. EGD showed a submucosal mass with extrinsic compression at the incisura and EUS showed a 8 cm hyperechoic mass in the epigastric region. FNA was negative for malignancy with extramedullary hematopoiesis with flow cytometry negative for B and T cell neoplasm. US-guided abdominal wall biopsy showed hematopoietic tissue with early myeloid, erythroid and megakaryocytic elements. Repeat CT scan A/P showed a part fat, part calcified mass increased to 7.3 x 7.6 x.5.5 cm. She followed up with surgical oncology with plans to discuss further workup at tumor boards. The patient prefers to avoid surgery and denies any symptoms of obstruction.

Discussion: We present an unusual case of extramedullary hematopoiesis of an abdominal mass which is not one of the common sites of EH. It is usually seen in patients with hematologic and infectious disorders, often without forming tumor-like masses mimicking neoplasm. Symptoms are usually due to masslike effect causing intestinal obstruction and gastric outlet obstruction. Pathogenesis of extramedullary hematopoiesis or extramedullary multiple myeloma are poorly understood. Imaging is not diagnostic but valuable for tissue sampling as histologic diagnosis is required for treatment. There is no standard therapeutic approach, with control of the primary disease being most important. Potential management options include transfusion therapy, radiotherapy, surgery, use of drugs such as hydroxyurea/steroids or a combination of modalities.



Disclosures:


Christin Wilkinson, MD¹, MaryKate Kratzer, MD², Karissa Lambert, MD³, Stephanie Ibarra Lepe, MD², Abdulazeez Swaiti, MD¹, Jinye Liu, DO², Christina Santana, MD², Amy Chang, MD², Saeed Graham, MD¹, Matthew Tugman, BA⁴, Michelle Cooley, BS⁴, Catherine Gray, BS⁴, Zarak Khan, MD³, Hassam Ali, MD¹, Rahul Pamarthy, MD¹, Prashant Mudireddy, MD³. P3215 - MGUS and the Mystery Mass: Unearthing Extramedullary Hematopoiesis With EUS Biopsy!, ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.