title: Paraneoplastic multicentric reticulohistiocytosis: a clinicopathologic challenge.
abstract: Multicentric Reticulohistiocytosis (MRH) is a rare, systemic non-Langerhans cell histiocytosis (non-LCH) with prominent joint and skin manifestations. It is mostly self limiting. However, 15-30% of the cases are associated with malignancy and carry a poor prognosis. We report the case of a 42-year-old man who presented with multiple reddish-brown papules that on biopsy showed aggregates of oncocytic histiocytes with several multinucleate giant cells. Immunostains were positive for CD 68, CD 45 and were negative for S-100, CD1a. An impression of multicentric reticulohistiocytosis (MRH) was made, with the recommendation to screen for malignancy. Electron microscopy of the skin lesions showed features consistent with non-Langerhans cell histiocytosis. The patient was later diagnosed with acute myeloid leukemia at a follow-up visit several months later. Thus, it appears prudent to screen and follow-up adults with MRH, to identify an underlying malignant condition.
authors.affiliation: Department of Pathology, St. John's Medical College and Hospital, Bangalore-560 034, India. rajnav@gmail.com
authors.forename: Rajalakshmi
authors.initials: R
authors.lastname: Tirumalae
authors.forename: Pritilata
authors.initials: P
authors.lastname: Rout
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Jayaseelan
authors.forename: Arun
authors.initials: A
authors.lastname: Shet
authors.forename: Shanthala
authors.initials: S
authors.lastname: Devi
authors.forename: Karuna Ramesh
authors.initials: KR
authors.lastname: Kumar
mesh_terms: D000328:Adult; D001706:Biopsy; D003937:Diagnosis, Differential; D015616:Histiocytosis, Non-Langerhans-Cell / Q000473:pathology*; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000150:complications*; D008297:Male; D010257:Paraneoplastic Syndromes / Q000209:etiology* / Q000473:pathology*