A 79-year-old male arrived by ambulance to our emergency department with chief complaints of nausea and vomiting after eating lunch. The patient was hypotensive and tachycardic on arrival and a physical exam was notable only for mild back pain and crackles in the left lower lung field. Past medical history included hypertension, type 2 diabetes mellitus, chronic kidney disease, and gastro-esophageal reflux disease which were all managed by medical therapy. As insufficient kidney function contraindicated contrast use, a non-contrast computed tomography (CT) scan was obtained (Fig. 1), which revealed massive left pleural effusion and significant mediastinal enlargement. Hence, an initial diagnosis of idiopathic esophageal rupture was made and the surgical team decided to proceed with emergency thoracotomy. The differential diagnoses considered at that time also included mediastinal hematoma, but not mediastinal mass, although the latter would have been considered if contrast CT images were available.
The patient was placed in the right lateral decubitus position and the thoracotomy incision was made along the left sixth intercostal space. Independent ventilation of the right lung was established prior to thoracotomy. A massive hemothorax was noted upon entering the left thoracic cavity. After draining approximately 2 l of blood, a large tumor roughly 20 cm in size, situated caudal and posterior to the heart in the lower posterior mediastinum became visible. The tumor compressed the surrounding structures, but was encapsulated and well demarcated. Careful examination revealed that a portion of the capsule had ruptured and was hemorrhaging into the thoracic cavity (Fig. 2a), however there was no sign of esophageal rupture or perforation. Cauterization of the ruptured site was ineffective and hemorrhage was profuse, therefore resection of the tumor was deemed necessary for hemostasis. The two options for curative surgery, enucleation and esophagectomy, were both deemed impractical for the situation. In addition to the sheer difficulty of enucleating such a large tumor, the benefit was questionable since the tumor capsule had already ruptured. Esophagectomy with gastric tube reconstruction was also difficult; the first-stage esophagectomy was highly risky because of the critical condition of the patient, and the second-stage reconstructive surgery would have been complicated by significant adhesions. Therefore, we proceeded with a “piecemeal” resection of the tumor, instead of enucleation or esophagectomy, by which the tumor was resected piece by piece primarily using electrothermal and harmonic scalpels. The esophagus was subsequently liberated and its adventitia was repaired using 4-0 absorbable sutures (Fig. 2b). Damage to the lower lobe of the right lung was also repaired and chest drains were placed in the dorsal left thoracic cavity. After closing the thoracic cavity, a percutaneous gastrostomy was performed to decompress the esophagus. Finally, an enterostomy was performed to enable enteral feeding during esophageal healing. Duration of the surgery was 3 h 49 min and total blood loss was 4 l. In summary, an emergency thoracotomy was used to accomplish “piecemeal” resection of a massive mediastinal tumor with no significant surgical complications.
Histologically, the tumor was composed of disarrayed fascicles of spindle cells with palely eosinophilic fibrillary cytoplasm (Fig. 3b). The mitotic rate was 2/50 HPFs. By immunohistochemistry, the tumor cells were diffusely positive for CD34 and c-kit (Fig. 3c, d). Desmin, S-100, AE1/AE3 and CD5 were negative. Thus, the tumor was diagnosed as an esophageal GIST of the spindle cell type. Because of the size of the tumor (> 10 cm), the patient was categorized as high-risk based on modified Fletcher classification and NCCN classifications.
The patient’s recovery from surgery was unremarkable. He was discharged on postoperative day 34. Adjuvant therapy with 400 mg imatinib mesylate daily was started as an outpatient, but discontinued after 1 month of therapy due to side-effects. The patient was offered second-line treatment with sunitinib, but declined because of his stable clinical status. Gastroscopy conducted at 2 months post-operation showed no sign of mucosal invasion or esophageal stricture (Fig. 4a). Positron emission tomography (PET) scan at 6 months, and CT scan at 10 months after surgery both demonstrated no sign of disease progression (Fig. 4b). We will continue to monitor the patient with imaging studies at least every 6 months for the foreseeable future. Restarting medical therapy will be considered if there are signs of disease progression.