Plasma Cell Myeloma and Plasma Cell Disorders

These are two schemas that encompass the reportable plasma cell neoplasms.

Plasma cell myeloma, also known as multiple myeloma, is one of the more common Hematopoietic neoplasms. It can present in an indolent phase (asymptomatic myeloma, smoldering myeloma). Information regarding the indolent phase is collected in a Schema Discriminator: Multiple Myeloma Terminology.

Plasma cell myeloma is histology 9732/3 and primary site is always C421. For EOD, only EOD Primary Tumor is applicable and is always coded 700. Summary Stage is always coded 7.

RISS Stage

The Revised International Staging System (RISS or R-ISS) is used to stage plasma cell myeloma. The stages are based on the absence or presence of the following related criteria

• 3931: Serum Beta-2 Microglobulin Pretreatment Level
• 3930: Serum Albumin Pretreatment Level
• 3857: High-risk cytogenetics
• 3869: LDH Level

See the SSDI manual or SEER*RSA for more information on these data items.

Plasma Cell Disorders Covers 4 Histologies

These histologies have default coding for EOD and Summary Stage. EOD Mets is not applicable for this schema and is coded to 88.

• 9731/3: Plasmacytoma, single, bone
  • EOD Primary Tumor: 100, EOD Regional Nodes: 987
  • Summary Stage: 1
• 9734/3: Plasmacytoma, single, extramedullary (outside of the bone)
  • EOD Primary Tumor: 200, EOD Regional Nodes: None, Positive, Unknown
  • Summary Stage: 1
• 9671/3: Lymphoplasmacytic lymphoma; 9761/3: Waldenstrom Macroglobulinemia
  • EOD Primary Tumor: 700; EOD Regional Nodes: 987
  • Summary Stage: 7

To use 9731/3 or 9734/3, there must be a SINGLE plasmacytoma. The presence of multiple plasmacytomas is plasma cell myeloma (9732/3).

Updated: December 2, 2025