Clinicopathological Features and Prognostic Differences Between Primary and Relapsed or Refractory Extramedullary...

Area of Science:

• Hematology
• Oncology
• Clinical Pathology

Background:

• Extramedullary multiple myeloma (EMM) is a rare manifestation of multiple myeloma (MM).
• Understanding the clinicopathological features and prognostic implications of EMM is crucial for patient management.
• Distinguishing between primary EMM (PEMM) and relapsed/refractory EMM (R/REMM) may impact treatment strategies and outcomes.

Purpose of the Study:

• To investigate the clinicopathological characteristics associated with extramedullary multiple myeloma (EMM).
• To compare the prognostic differences between patients with primary EMM (PEMM) and relapsed or refractory EMM (R/REMM).

Main Methods:

• Retrospective analysis of 203 multiple myeloma (MM) patients.
• Categorization into EMM-positive (EMM+) and EMM-negative (EMM-) groups.
• Subgroup analysis of EMM+ patients into PEMM and R/REMM groups based on occurrence time.

Main Results:

• EMM incidence was 24.6%, with PEMM at 16.3% and R/REMM at 8.4%.
• EMM+ patients showed lower CD20+ expression and higher rates of elevated β2-MG and serum calcium.
• R/REMM was associated with plasma cell leukemia and lower albumin levels, and significantly poorer overall survival (OS) compared to PEMM.

Conclusions:

• Relapsed or refractory extramedullary multiple myeloma (R/REMM) is an independent adverse prognostic factor in MM patients.
• Primary EMM (PEMM) did not show a significant association with overall survival.
• R/REMM is linked to specific clinical indicators like plasma cell leukemia and hypoalbuminemia.