Long-term survival after conversion surgery for an esophageal neuroendocrine carcinoma: a case report

Esophageal neuroendocrine carcinomas (NECs) are extremely rare. Published information on their clinical features, pathological findings, and prognosis is lacking. The optimal treatment for esophageal NECs has not yet been determined because they appear extremely malignant histologically and have a poor prognosis. We here report on a patient with an esophageal NEC who was successfully treated with multidisciplinary therapies.

The patient, a 47-year-old man, was admitted to our hospital with dysphagia and weight loss and an ECOG performance status of 3-4. Upper endoscopy showed a large circumferential neoplasm at the esophagogastric junction. Computed tomography showed lymph node metastases around the left gastric artery. Echocardiography raised a suspicion of invasion of the left atrium. Histopathological examination of biopsy tissue revealed diffuse proliferation of small atypical cells resembling naked nuclei with extensive necrosis and degeneration. The cells showed positive staining for CD56, chromogranin A, and synaptophysin on immunohistochemical analysis. Ki67 was positive in over 90% of cells. He was diagnosed with an esophageal NEC that had infiltrated the left atrium; his cancer was therefore inoperable. Because of his poor overall condition, palliative radiotherapy (30 Gy in 15 fractions) was administered, accompanied by nutritional management. This was followed by four courses of chemotherapy with carboplatin plus etoposide, after which the primary tumor and locoregional lymph node metastases were found to have shrunk. Thoracoscopic- and laparoscopic-assisted McKeown esophagectomy were performed. The postoperative pathological diagnosis was NEC pT3pN0M0 Stage II. The patient had a good postoperative course and received two courses of postoperative adjuvant chemotherapy (carboplatin plus etoposide). Currently, 3 years after commencing treatment, there is no evidence of recurrence.

As mentioned above, there is no established treatment regime for esophageal NEC, and the benefits of conversion surgery are unknown. Our patient achieved long-term recurrence-free survival after radiation therapy, chemotherapy, and surgery for an esophageal NEC with left atrial invasion and multiple lymph node metastases. Conversion surgery for esophageal NECs that respond to chemotherapy may contribute to long-term survival.