Case Presentation:

A 27-year-old male with no past medical history was seen in clinic for a pre-employment screening and complained of intermittent chest pain that occurred while at rest.  He had a maternal grandfather who had lung cancer and a maternal great grandmother who had an unknown cancer.  He had no significant social history.  On physical exam, he had a left upper sternal border systolic murmur but an otherwise normal exam.  A transthoracic echocardiogram showed a 4.8 X 3.5 cm bi-lobed mass attached to the right ventricular outflow tract (RVOT) and pulmonary artery (PA).  A computed tomography angiography (CTA) showed a large mediastinal mass invading the main and right PA, pulmonic valve and aortic root and encasing the ascending aorta, aortic arch, trachea, and left mainstem bronchus.  The origin of the tumor appeared to be from either the middle mediastinum or interventricular septum.  Tumor markers including β-hcg, AFP, CEA, and CA 19-9 were negative.  Endobronchial ultrasound with aspiration and right heart catheterization (RHC) biopsy of the intra-cardiac portion of the mass were non-diagnostic.  Soon after the RHC, he developed severe back pain.  A CT with pulmonary emboli (PE) protocol showed bilateral PEs.  Subsequently, he developed right leg pain and was found to have a deep venous thrombosis in the common femoral vein.  An IVC filter was placed and he remained on enoxaparin.  Histologic examination of the tissue from a CT guided needle biopsy favored IgG4 sclerosing inflammatory pseudotumor.  Immunohistochemical stains for IgG and IgG4 were uninterpretable and serum IgG4 levels were within normal limits.  After ruling out infection, the rheumatology service recommended starting the patient on a prolonged steroid taper.  Three months after discharge, he had a repeat chest CT that showed a small interval decrease in the size of the RVOT mass and he currently remains on a steroid taper.


Immunoglobulin G4-related disease is an increasingly recognized immune-mediated condition that includes tumor-like organ swelling, IgG4 plasma cell rich lymphoplasmacytic infiltrate, and variable fibrosis.  Serum IgG levels may be normal in 30-40% of patients.  It occurs more commonly in middle aged and older males.  Lymphadenopathy is common, and symptoms of asthma or allergy are present in approximately 40% of patients.  The majority of patients respond to glucocorticoids particularly in early stages of the disease.


Chest pain is a very common presenting symptom among admitted adult patients.  Despite the size and extent of the thoracic mass in this patient, he initially presented only with vague intermittent symptoms.  This case represents an interesting and unique etiology of chest pain and a diagnosis that may become increasingly recognized.