Pseudo-Peritoneal Carcinomatosis Presentation of a Crystal-Storing Histiocytosis With an Unmutated Monoclonal κ Light Chain.
Crystal-storing histiocytosis (CSH) is a rare complication of monoclonal gammopathies caused by accumulation of crystalline material inside macrophages, and it may result in a variety of clinical manifestations depending on the involved organs. Although immunoglobulin κ light chains (LCs) seem to be the most frequent pathogenic component, very few molecular data are currently available.A 69-year-old man presented with a very poor performance status. Remarkable features were mesenteric lymph node enlargement and proteinuria, including a monoclonal κ LC. Light and electron microscopy studies revealed the presence of crystals within macrophages in the lymph nodes, bone marrow, and kidney, leading to the diagnosis of CSH. The pathogenic κ LC variable domain sequence was identical to the germline Vk3-2001/Jk201 gene segments, without any somatic mutation, suggesting an extra-follicular B cell proliferation.The patient was successfully treated with 4 cycles of bortezomib and dexamethasone. After a 12-month follow-up, he remains in hematological and renal remission.CSH may present as pseudo-peritoneal carcinomatosis and relate to a monoclonal κ LC encoded by an unmutated gene. Bortezomib-based therapy proved efficacious in this case.
From the AP-HP (AA-F, BF), Hôpital Saint Antoine, Department of Pathology, Paris; CNRS UMR 7276 Université de Limoges (SB, MCV), Hôpital Universitaire Dupuytren; AP-HP (DB), Hôpital Tenon, Department of Pathology, Paris; Université Pierre et Marie Curie-Paris 6 (DB), Paris; Centre hospitalier de Troyes (SB), Service D'Hématologie; AP-HP (MM), Hôpital Saint-Antoine, Service d'Hématologie Clinique et Thérapie Cellulaire, Paris; Université Pierre & Marie Curie (MM), Paris; INSERM (MM), UMRs, U938, Paris; AP-HP (PR, JJB), Hôpital Tenon, Department of Nephrology and Dialysis, Paris; Sorbonne Universités (PR, JJB), UPMC Univ Paris 06, UMR_S 1155; INSERM (PR, JJB), UMR_S 1155, Paris; INSERM (PA), UMRS 938, Hôpital Saint-Antoine, Paris; Université Pierre et Marie Curie-Paris6 (PA), Hôpital Saint-Antoine, Paris; INSERM (LG), UMR_S 938, Paris; AP-HP (LG), Hôpital Saint Antoine, Département d'hématologie et de thérapie cellulaire, Paris; and Université Pierre et Marie Curie-Paris6 (LG), Paris, France.
Aude
A
Aline-Fardin
Sebastien
S
Bender
Bettina
B
Fabiani
David
D
Buob
Said
S
Brahimi
Marie Christine
MC
Verpont
Mohamad
M
Mothy
Pierre
P
Ronco
Jean Jacques
JJ
Boffa
Pierre
P
Aucouturier
Laurent
L
Garderet
D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use; D001897:Boronic Acids / Q000627:therapeutic use; D000069286:Bortezomib; D003460:Crystallization; D015614:Histiocytosis / Q000150:complications / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000235:genetics*; D007668:Kidney / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008264:Macrophages / Q000737:chemistry; D008297:Male; D008998:Monoclonal Gammopathy of Undetermined Significance / Q000150:complications* / Q000188:drug therapy / Q000473:pathology; D010534:Peritoneal Neoplasms / Q000150:complications*; D011719:Pyrazines / Q000627:therapeutic use
D000970:Antineoplastic Agents; D001897:Boronic Acids; D007145:Immunoglobulin kappa-Chains; D011719:Pyrazines; D000069286:Bortezomib