title: Bence-Jones protein-type myeloma with amyloid myopathy presenting as amyloidomas and extensive amyloid deposits in the muscularis propria: a rapidly fatal autopsy case.
abstract: This study reports a 59-year-old man who suffered from multiple skeletal muscle amyloidomas and showed a rapidly fatal course. He noticed left inguinal pain and gait disturbance due to muscle weakness of the left leg. Protein in urine (3.3 g/d) and Bence-Jones protein of the κ type (2.3 g/d) were detected. Bone marrow aspiration showed 11.6% monoclonal plasma cells in nucleated cells. A core needle-biopsied and resected left inguinal tumor showed the deposition of eosinophilic amorphous materials positive for Congo red stain and the κ-light chain. He was diagnosed with plasma cell myeloma with AL (amyloid light chain) amyloidosis. Multiple soft-part tumors developed, grew rapidly, and he died 3 months after admission. At autopsy, 3 large amyloidomas were observed in the skeletal muscles, and prominent amyloid deposits were also seen in the diaphragm, intercostal muscle, iliopsoas muscle, and cervical skeletal muscles examined. Massive amyloid materials deposited diffusely in the propria muscularis of the gastrointestinal tract: the tongue to the rectum.
authors.affiliation: Department of Pathology, Mito Saiseikai General Hospital, Mito, Ibaraki, Japan.
authors.forename: Yoshiyasu
authors.initials: Y
authors.lastname: Ikezawa
authors.forename: Kuniyuki
authors.initials: K
authors.lastname: Oka
authors.forename: Reizo
authors.initials: R
authors.lastname: Nagayama
authors.forename: Yuki
authors.initials: Y
authors.lastname: Okubo
authors.forename: Nobuo
authors.initials: N
authors.lastname: Yonekawa
authors.forename: Futoshi
authors.initials: F
authors.lastname: Hirai
authors.forename: Itaru
authors.initials: I
authors.lastname: Ebihara
authors.forename: Naoyoshi
authors.initials: N
authors.lastname: Mori
mesh_terms: D000686:Amyloidosis / Q000150:complications / Q000473:pathology*; D001344:Autopsy; D001536:Bence Jones Protein / Q000378:metabolism; D017809:Fatal Outcome; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000150:complications / Q000473:pathology*; D018482:Muscle, Skeletal / Q000473:pathology*; D009135:Muscular Diseases / Q000209:etiology / Q000473:pathology*
chemical_list: D007145:Immunoglobulin kappa-Chains; D001536:Bence Jones Protein