Paraneoplastic autoimmune multiorgan syndrome (PAMS) is a heterogeneous autoimmune condition that can occur as a complication of neoplasia, most frequently lymphoproliferative disorders, such as non-Hodgkin lymphomas, chronic lymphocytic leukemia and Castleman disease (CD) [1]. The most common manifestations of PAMS are paraneoplastic pemphigus (PNP) that encompasses a range of mucocutaneous lesions, and respiratory involvement in the form of bronchiolitis obliterans (BO) [2]. The pathophysiological mechanism involves humoral and cell-mediated autoimmunity responses to antigens produced by the underlying disease [[2], [3], [4], [5], [6], [7]].

Clinically, the mucocutaneous disease is characterized by severe polymorphous skin lesions and painful mucosal erosions which correspond to acantholytic changes with interface dermatitis and lichenoid eruptions at the histopathologic level [1,[8], [9], [10]]. In a subset of patients, respiratory symptoms may develop, typically following the emergence of the mucocutaneous lesions and generally late in the course of the disease. These symptoms often include chronic cough and progressive dyspnea that may ultimately lead to respiratory failure and death. Fibrous obliteration of bronchioles is the histologic hallmark of BO. Respiratory involvement is particularly common in patients with CD compared with other neoplasms and among CD, the hyaline vascular subtype, stroma-rich variant is positively correlated with the incidence of PAMS [[11], [12], [13]].

Removal of the underlying neoplasm is the most important step in the treatment of patients with PAMS and may lead to resolution of the mucocutaneous lesions and eventual disappearance of autoantibodies [6]. Immunosuppressive therapy is warranted in patients with non-operable tumors, however, PAMS is often resistant to such treatment and mortality rates as high as 75 % to 90 % have been reported, especially in patients with respiratory involvement [6,14]. In fact, BO has been found to be a particularly poor prognostic factor for patients with PAMS [15,16].

Here, we report a case of patient with a pre-existing unicentric CD, hyaline vascular and stroma-rich variant who developed PAMS 7 years after the initial identification of a paratracheal tumor. The patient has recently undergone lung transplantation due to progressive respiratory involvement. A review and update of the existing literature is also provided.