Clinical and pathological characteristics of 107 esophageal neuroendocrine carcinoma

Objective To investigate the clinical and pathological features of patients with esophageal neuroendocrine carcinoma (ENEC). Methods From January 2011 to November 2018, 107 patients with pathologically confirmed ENEC were enrolled at the First Affiliated Hospital of Zhengzhou University. The clinical manifestation, tumor location, tumor size, clinical pathological classification and immunohistochemical markers were analyzed. Statistical description was used for measurement data analysis, and chi-square test was performed for classification data analysis. Results Among 107 patients with ENEC, feeling obstruction during eating was the most common initial symptom, accounting for 63.6%(68/107); followed by chest and back pain, accounting for 13.1%(14/107). About 60.7%(65/107) patients were diagnosed by biopsy under endoscopy and 39.3% (42/107) patients were confirmed by pathological diagnosis after surgery. The proportion of tumor located in the upper thoracic esophagus and middle and lower thoracic segments was 13.1%(14/107), 45.8%(49/107) and 41.1%(44/107), respectively. The length of tumor was 0.7 cm to 9.0 cm, and the median was 2.5 cm. Among them, 57.0%(61/107) were less than 2.5 cm and 43.0%(46/107) were over 2.5 cm. Among 107 patients, 50 (46.7%) patients were ulcerative type, 32 (29.9%) patients were medullary type, 16 (15.0%) patients were mushroom type and nine (8.4%) patients were protrude type. Among 107 patients, 96 (89.7%) patients were pure neuroendocrine carcinoma (P-NEC; including 95 small cell types, one large cell type); 11 (10.3%) patients were mixed neuroendocrine carcinoma (M-NEC; including nine small cell carcinoma mixed with squamous cell carcinoma, two small cell carcinoma mixed with adenocarcinoma). The positive rates of synaptophysin, CD56 and chromogranin A were 99.0%(104/105), 98.0%(100/102) and 31.5%(17/54), respectively. Ki-67 proliferation index of 47.7% tumors (51/107) was between 90% and 100%. P-NEC with the maximum diameter over 2.5 cm accounting for 42.1%(45/107), and M-NEC accounting for 0.9%(1/107). The maximum diameter of P-NEC group was larger than that of M-NEC group, and the difference was statistically significant (χ2=4.311, P=0.038). Conclusions ENEC is a kind of highly aggressive malignant tumor with nonspecific manifestations. The diagnosis mainly depends on histopathology and immunohistochemistry. Key words: Carcinoma, neuroendocrine; Esophagus; Immunohistochemistry; Pathology; Clinic