Small cell B-cell lymphoma, unspecified site

This code identifies a malignant neoplasm originating from small B-lymphocytes, characterized by a diffuse growth pattern. It represents a specific type of non-Hodgkin lymphoma where the primary site of involvement is not documented or is unknown. This condition is typically aggressive and requires systemic treatment.

Use this code when the medical record clearly documents a diagnosis of small cell B-cell lymphoma, but the specific anatomical location of the tumor is not specified. This is appropriate for initial diagnoses where the extent of disease is still being evaluated or when the primary site cannot be determined. Documentation must explicitly state "small cell B-cell lymphoma" without a specified site.

• Do not use this code if a specific anatomical site (e.g., lymph nodes of head, spleen) is documented; instead, use a more specific C83.0- subcategory.
• Always review pathology reports and physician notes for precise B-cell lymphoma subtypes and site specificity.
• Consider sequencing this code as the primary diagnosis when it is the reason for the encounter and no further site specificity is available.