Updates in staging and pathologic evaluation of esophageal carcinoma following neoadjuvant therapy

Esophageal carcinoma comprises two major subtypes-squamous cell carcinoma and adenocarcinoma, the incidences of which vary widely across the world and also depend on the location within the esophagus. The staging of esophageal cancer (EC) also remains unique among various gastrointestinal carcinomas, as it takes into account the location, histologic type, and grade. Its management has been evolving over the years and the recent American Joint Committee on Cancer staging system has been updated to reflect the changing practice and new data. It is clear that preoperative neoadjuvant therapy is increasingly being used for the treatment of locally advanced esophageal carcinomas, followed by surgical resection that improves survival. A variety of histologic changes can be seen after neoadjuvant therapy, which can be challenging for the pathologists. The presence of residual tumor in the surgically resected specimen and lymph node following neoadjuvant therapy is associated with poor prognosis. Hence, a thorough pathologic assessment of tumor regression grade and accurate tumor staging is required by pathologists to provide valuable prognostic information to guide further management. Tumor regression grading in ECs needs to be improved and standardized.