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Presacral extramedullary hematopoiesis: an alternative hypothesis
Mohamed Macki1, Mohamad Bydon, Kyriakos Papademetriou
1Department of Neurosurgery, Johns Hopkins University School of Medicine, Meyer Building, Room 5-109, 600 N. Wolfe Street, Baltimore, MD 21287, USA; Johns Hopkins Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, USA.
Summary
Idiopathic extramedullary hematopoiesis (EMH) is rare, occurring outside bone marrow without blood disorders. This case highlights presacral EMH, potentially linked to prior surgery, managed conservatively.
Area of Science:
- Hematology
- Pathology
- Surgical Oncology
Background:
- Idiopathic extramedullary hematopoiesis (EMH) involves blood cell production outside the bone marrow.
- This condition typically lacks an underlying hematological pathology.
- Presacral EMH is exceptionally rare.
Observation:
- A 65-year-old woman presented with back and leg pain, with MRI revealing a presacral mass.
- Diagnosis of EMH was confirmed via fine needle aspiration.
- The patient had a history of total abdominal hysterectomy.
Findings:
- The study presents a rare case of idiopathic presacral EMH.
- Two potential pathophysiological mechanisms are proposed: sacral fractures releasing hematopoietic stem cells, or surgical manipulation of uterine tissue releasing mesenchymal stem cells.
- These stem cells interact to form the EMH mass.
Implications:
- Idiopathic presacral EMH may arise from bone trauma or gynecological surgery.
- Conservative management with serial imaging is recommended.
- Intervention is reserved for cases with intractable pain, neurological deficits, or bowel/bladder dysfunction.
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