ISSN: 2584-2153 (Online)
Title: OLCIAS Journal
EXTRAOSSEOUS RETROVERTEBRAL TUMOR IN MULTIPLE MYELOMA: A Rare Diagnostic Challenge
BACHIR PACHA AEK, SIALI Ismail, BERDI FZ; HAMOUCHE Hanane, CHIKH Djahida,
and BADACHE Kenza
Department of Neurosurgery, University Hospital Center of Mostaganem, Mostaganem,
Algeria
Corresponding author: BACHIR PACHA AEK, Department of Neurosurgery,
University Hospital Center of Mostaganem, Mostaganem, Algeria
Received: November 15, 2025 — Accepted:December 30, 2025 — Published: January 30, 2026
Citation : BACHIR PACHA AEK, SIALI Ismail, BERDI FZ; HAMOUCHE Hanane, CHIKH Djahida,
and BADACHE Kenza. EXTRAOSSEOUS RETROVERTEBRAL TUMOR IN MULTIPLE MYELOMA:
A Rare Diagnostic Challenge. OLCIAS Vol.3, Issue 1
Abstract:
Background: Multiple myeloma is a malignant plasma cell disorder that predominantly affects the axial skeleton, particularly the spine. Pure extraosseous paraspinal involvement without bone destruction is exceptionally rare.
Case Report: We report a 63-year-old woman with multiple myeloma receiving chemotherapy who was admitted for evaluation of a rapidly enlarging posterior dorsolumbar mass. Clinical examination revealed a firm, minimally tender subcutaneous mass extending from T12 to L3, fixed to deep planes and in contact with the spinous processes. Spinal MRI demonstrated a posterior retrovertebral paraspinal mass, isointense on T1-weighted images, hyperintense on T2-weighted images, with gadolinium enhancement, and no evidence of bone lysis or intraspinal extension. Complete surgical excision was performed for diagnostic and therapeutic purposes. Histopathology confirmed a plasmacytoid tumor proliferation consistent with extramedullary myeloma.
Conclusion: Extraosseous soft-tissue involvement of multiple myeloma in the posterior paraspinal/subcutaneous region without vertebral destruction is a rare diagnostic entity, for which MRI is pivotal, and surgery provides both diagnosis and local control. (1–5,7,8).
Keywords: Multiple myeloma; Extramedullary disease; Paraspinal mass; Retrovertebral tumor; MRI; Plasmacytoma; Neurosurgery