Primary gastric amyloidosis associated with linitis plastica and delayed progression to systemic amyloidosis and multiple myeloma.

We report the case of a woman in her 50s who underwent, 5 years prior, a total gastrectomy after neoadjuvant chemotherapy for diffuse-type gastric cancer diagnosed during a workup for isolated gastric primary light chain (AL) amyloidosis. At the time of diagnosis, immunoglobulins light chain measurements and bone marrow biopsy were performed to rule out multiple myeloma and came back normal. Three years later, the patient developed systemic amyloidosis involving the heart and the lungs, after which she developed multiple myeloma. Isolated amyloid deposits in the stomach are a rare finding. While AL amyloidosis is frequently found in concomitance with multiple myeloma, late progression of primary AL amyloidosis to systemic amyloidosis and multiple myeloma is uncommon.