Introduction

• Usually occur in skin and oral cavity but also reported in GI tract, spleen, LNs.
• Rare.
• Usually benign.
• Unrelated to multiple myeloma Myeloma and may be associated (rare) with paraneoplastic disease (hyperproteinemia).
• Cause: neoplastic proliferation of plasma cells at a site distant from bone marrow.
• Signs: found in skin and oral cavity, but also reported in GI tract, spleen, lymph nodes. Usually solitary, dome-shaped alopecic nodules in skin but can be multiple.
• Predilection sites on head, feet, lips and ear canal but can occur anywhere.
• Diagnosis: histopathology.
• Treatment: surgical resection, radiotherapy, chemotherapy.
• Prognosis: good for skin lesions.

Pathogenesis

Pathophysiology

• Solitary proliferation of neoplastic plasma cells at a site distant from the bone marrow → rarely associated with paraneoplastic disease (monoclonal gammopathy).
• GI forms more aggressive than skin form and may metastasize.

• Solitary proliferation of neoplastic plasma cells at a site distant from the bone marrow.
• Local cutaneous or oral problem usually.
• May occur at multiple sites in skin (not necessarily metastases).
• Spread to local lymph nodes quite common if in GI tract (not usually if in skin).
• May be associated with paraneoplastic disease (monoclonal gammopathy).

Timecourse

• Weeks.

Diagnosis

Treatment

Outcomes