[CA 19-9 Secreting Extralobar Sequestration Presenting as a Bifocal Posterior Mediastinal Tumour].

A 60-year-old female patient was referred for further diagnosis and treatment of a posterior mediastinal lesion. The lesion was incidentally discovered in a CT scan of the chest and abdomen, which had been performed due to an increased CA 19-9 in routine blood tests. At the time point of the referral, the lesion had already been biopsied twice (CT guided and through EUS) but the histopathology was inconclusive. Upon referral, we repeated the CT guided biopsy and the transoesophageal ultrasound. The latter did not reveal any invasion of the oesophagus. Both biopsies were inconclusive again. We discussed thoracoscopic exploration with the patient. The procedure began with a right uniportal VATS. The lesion originated in the right lower lobe. After dissection of the lesion from the right lower lobe and its adhesions to the diaphragm, the lesion was mobilised from the mediastinal adhesions. A supplying vessel from the descending aorta was ligated and the patient was turned in order to continue the procedure from the left side. During the left sided thoracoscopy, the lesion was dissected from the diaphragm and the descending aorta. There was no invasion of the lung on the left side. The lesion was pulled through the mediastinum between the aorta and the oesophagus and was successfully extracted through the left uniportal incision. The histopathological report revealed extralobar pulmonary sequestration.