From the archives of MD Anderson Cancer Center: Paraneoplastic autoimmune multiorgan syndrome (PAMS) associated with stroma-rich Castleman disease.

Paraneoplastic autoimmune multiorgan syndrome (PAMS) is a rare, often fatal condition that occurs in association with a range of neoplasms, most commonly lymphoproliferative disorders. PAMS often presents as paraneoplastic pemphigus, an autoimmune bullous disease affecting the skin and mucosal surfaces and bronchiolitis obliterans, a small airway disease that can result in respiratory failure and death. We describe a 39-year-old woman with an incidentally discovered paratracheal mass that was followed clinically. Seven years later, she developed ulcerative oral lesions followed by progressive dyspnea. Biopsy of the oral lesions showed intraepithelial clefting and interface mucositis. Immunofluorescence and serologic studies revealed IgG and complement deposition within intercellular epithelial spaces and along the basement membrane zone, together with circulating anti-plakin antibodies, establishing a diagnosis of paraneoplastic pemphigus. Resection of the paratracheal mass revealed lymphoid tissue with follicular and interfollicular stromal changes, atretic germinal centers and thickened mantle zones, consistent with unicentric Castleman disease, stroma-rich hyaline vascular variant. Wedge resection of the lung showed focal bronchiolar scarring supporting the clinical impression of bronchiolitis obliterans. The patient was treated with steroids and rituximab and recently underwent bilateral lung transplantation due to progressive respiratory symptoms. This report underscores a rare and potentially life-threatening complication of Castleman disease and presents an updated review of the literature. Bronchiolitis obliterans, in particular, has been identified as a marker of poor prognosis in patients with PAMS and lung transplantation often represents the only viable treatment option once the underlying neoplasm has been controlled.