Unsp B-cell lymphoma, lymph nodes of axilla and upper limb

This code signifies a malignant proliferation of unspecified B-lymphocytes, originating or primarily affecting the lymph nodes located in the axilla and/or upper limb. It represents a diagnosis of B-cell lymphoma where the specific subtype (e.g., diffuse large B-cell, follicular) has not been determined or documented.

Use this code when the medical record clearly documents a diagnosis of B-cell lymphoma affecting the axillary or upper limb lymph nodes, but the pathologist or clinician has not specified the exact B-cell subtype. This often occurs during initial diagnostic workup or when a more definitive diagnosis is pending. Documentation should explicitly state "unspecified B-cell lymphoma" and specify the axillary/upper limb involvement.

• Avoid using this code if a more specific B-cell lymphoma subtype (e.g., C83.34 for diffuse large B-cell lymphoma of axilla and upper limb) is documented.
• Ensure the documentation clearly links the lymphoma to the axillary and/or upper limb lymph nodes; do not use for generalized or other specified sites.
• If the laterality (right/left) is known, but not specified in the code, it is still appropriate to use this code as it does not differentiate laterality.