New treatments, new challenges: pathology's perspective on esophageal carcinoma.

While frank esophageal carcinoma rarely presents a diagnostic challenge, early lesions are often tricky to assess. This difficulty stems in part from drawbacks in the classification systems designed to stratify early lesions as a guide for deciding treatment. These systems are complex and wrought with specific pathologic challenges brought on by new treatment modalities. Such interventions as endoscopic mucosal resection, photodynamic therapy, and chemotherapy/radiation combinations present the pathologist with new histologic challenges that have a direct impact on patient care. In this article, we discuss staging issues pertinent to early cancers, histologic sequelae of various treatments, and how these factors affect the pathologist's role in evaluating esophageal carcinoma.