C90.30

HCC Category Mapping

What This Code Means

A single tumor made of plasma cells that has not responded to treatment or achieved remission.

Coding Tips

• •Solitary plasmacytoma is a single lesion; if multiple lesions are present, consider multiple myeloma codes instead
• •Document the treatment response status; 'not having achieved remission' means the patient has not reached remission status

Clinical Significance

Solitary plasmacytoma (of bone) is a single osseous lesion composed of neoplastic plasma cells without evidence of systemic multiple myeloma. It most commonly affects the axial skeleton, particularly the vertebrae. Without achieving remission, there is a significant risk of progression to multiple myeloma, which occurs in approximately 50-65% of cases within 10 years. The lesion may cause pathologic fractures and spinal cord compression.

Documentation Requirements

• ✓Documentation must include tissue biopsy confirming a monoclonal plasma cell tumor in bone.
• ✓Imaging confirming a single bone lesion with no additional skeletal involvement, bone marrow biopsy excluding myeloma, serum and urine protein electrophoresis, and treatment approach (typically radiation) must be documented.
• ✓Non-remission status and any structural complications must be recorded.

Commonly Confused Codes