Carcinosarcoma of the Esophagus-A Diagnostic Challenge

Background: Esophageal carcinosarcoma is an uncommon histologic variant of esophageal malignancy, occurring in approximately 0.5% to 2.8% of patients. Esophageal carcinosarcoma usually involves the middle and lower esophagus and consists of both epithelial and mesenchymal components. Case Report: A 54-year-old male presented with painless progressive dysphagia associated with loss of weight for 2 months. Esophagogastroduodenoscopy suggested an ulceroproliferative polypoidal growth in the lower thoracic esophagus. Biopsies from the growth showed leiomyosarcoma with tumor cells immunopositive for vimentin, h-Caldesmon, and smooth muscle actin and negative for pan-cytokeratin. Imaging suggested a heterogeneously enhancing polypoidal growth arising in the lower third of the esophagus. Thoracoscopic-assisted McKeown esophagectomy with gastric pull-up and standard 2-field lymphadenectomy was performed. A minor epithelial component was identified on final pathologic examination in addition to the leiomyosarcoma found on the preoperative biopsy. This epithelial component was invasive squamous cell carcinoma and was positive for pan-cytokeratin and p40, both of which were negative in the sarcomatous component. The patient received 4 cycles of adjuvant chemotherapy (carboplatin and paclitaxel). However, he developed a recurrence in the left cervical lymph node 4 months after adjuvant treatment and died 2 months after the diagnosis of recurrence. Conclusion: Carcinosarcoma can be easily missed in the presence of predominantly sarcomatous components even on immunohistochemical analysis. These tumors may be associated with poor prognosis and may have early recurrence despite surgery and adjuvant treatment.