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SEER Inquiry System - Report
Produced: 06/16/2026 9:18 AM
Question 20130044
Inquiry Details
References:
Heme & Lymph Manual & DB
Question:
Discussion:
On 2/3/12 the patient was diagnosed via biopsy with an extraosseous (extramedullary) plasmacytoma filling both nasal cavities. On 2/16/12 a metastatic workup was performed and showed a lucent lesion in calvarium of Rt frontal bone. 2/17/12 radiation oncology consult states, "I believe this is most likely consistent with multiple myeloma." Subsequently, the 3/1/12 CT of the left shoulder showed a 3.6 cm lytic lesion of humeral head with cortical breakthrough consistent with metastasis or myeloma.
Per the Heme DB, extramedullary plasmacytoma can transform to multiple myeloma. Does that make this multiple primaries with the histologies coded to 9734/3 and 9732/3?
Answer:
Updated May 2026
This case should be accessioned as a single primary, multiple myeloma [9732/3] diagnosed on 2/3/12 per Rule M8. Abstract the acute neoplasm as a single primary when both a chronic and acute neoplasm when they are both diagnosed during the initial clinical workup AND there is documentation of only one positive tissue biopsy.
This patient only had a tissue biopsy of the nasal cavity proving the chronic neoplasm (extraosseous plasmacytoma). The acute neoplasm (multiple myeloma) was diagnosed clinically based on the scans.
