title: Cutaneous malakoplakia simulating relapsing malignant lymphoma.
abstract: This report describes the case of a 42-year-old man with malignant lymphoma, diffuse large non-cleaved cell type, who developed cutaneous malakoplakia in the left groin. The patient had widespread lymph node involvement, including a left inguinal mass which was clinically thought to represent recurrent lymphoma. The inguinal mass failed to regress after chemotherapy and irradiation, although lymphoma in other sites responded to chemotherapy. A skin biopsy of the area showed an ulcer and an abscess involving the dermis and subcutaneous tissue. Microscopically, a diffuse infiltrate of foamy histiocytes was seen with numerous intracellular and extracellular, round and laminated bodies. Some of these bodies had a "targetoid" appearance, stained strongly with von-Kossa's calcium stain and showed the typical appearance of Michaelis-Gutmann bodies by electron microscopy. Cultured monocytes from the peripheral blood of the patient showed ultrastructural features similar to their tissue counterparts, suggesting a systemic involvement of the monocyte macrophage lineage. This case represents an unusual presentation of malakoplakia of the skin associated with relapsing malignant lymphoma in a patient on immunosuppressive drugs.
authors.affiliation: Department of Pathology, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111.
authors.forename: J P
authors.initials: JP
authors.lastname: Palazzo
authors.forename: D J
authors.initials: DJ
authors.lastname: Ellison
authors.forename: I E
authors.initials: IE
authors.lastname: Garcia
authors.forename: C
authors.initials: C
authors.lastname: Langer
authors.forename: R M
authors.initials: RM
authors.lastname: Scher
authors.forename: J P
authors.initials: JP
authors.lastname: Hoffman
authors.forename: R O
authors.initials: RO
authors.lastname: Petersen
mesh_terms: D000328:Adult; D006119:Groin; D006258:Head and Neck Neoplasms / Q000473:pathology* / Q000648:ultrastructure; D006644:Histiocytes / Q000648:ultrastructure; D006801:Humans; D002479:Inclusion Bodies / Q000648:ultrastructure; D008207:Lymphatic Metastasis; D008223:Lymphoma / Q000473:pathology* / Q000648:ultrastructure; D008287:Malacoplakia / Q000473:pathology*; D008297:Male; D009364:Neoplasm Recurrence, Local / Q000473:pathology* / Q000648:ultrastructure