S1.

WHO classification of esophageal carcinomas (referring to WHO classification of tumors of the digestive system. 2010)

Histological type	ICD-O code
Squamous cell carcinoma	8070/3
Rare variants:
Verrucous carcinoma	8051/3
Spindle cell squamous cell carcinoma	8074/3
Basaloid squamous cell carcinoma	8083/3
Adenocarcinoma	8140/3
Mucoepidermoid carcinoma	8430/3
Undifferentiated carcinoma	8020/3
Neuroendocrine neoplasms:
Neuroendocrine tumors (NET)
NET G1	8240/3
NET G2	8249/3
Neuroendocrine carcinomas (NEC)	8246/3
Small cell carcinoma	8041/3
Large cell neuroendocrine carcinoma	8013/3
Mixed adenoneuroendocrine carcinoma	8244/3