A 45-year-old woman underwent one year ago mastectomy followed by chemo and radiation therapy. She now complains of dyspnea at rest and temperature up to 37.2°C. Her general condition is severe, acrocyanosis is observed. The right side of her chest practically does not participate in respiration. Percussion reveals a dull sound below the 3rd rib; auscultation detects acute weakening of the respiratory sounds. Pleural puncture on the right has yielded a large amount of hemorrhagic exudate. What complication has developed in the patient?