Esophageal carcinoma cuniculatum. Systematic review of the literature and report of two cases

Background and Aims: Carcinoma cuniculatum (CC) is a rare variant of an extremely well-differentiated squamous cell carcinoma. The most commonly involved site is the skin, with a preference for the sole. Only 15 cases of esophageal CC have been reported so far. Based on published data, the clinical behavior of CC has not been clearly defined. We describe the clinical-pathologic features of two cases of esophageal CC, and provide a review of the available literature, to shed more light on this unusual tumor. Methods: A detailed gross and histologic analysis was performed on two cases of surgically treated esophageal CC. The patients were followed-up after surgery. A systematic search was also done concerning studies focused on esophageal CC. A search of the electronic databases MEDLINE-PubMed was conducted using the following research terms: (esophagus) AND (cuniculatum carcinoma). Results: Both patients were alive at last follow-up at six and nine months from surgery without any recurrence. Concerning the fifteen cases reported from the systematic review, median follow-up after surgery was very long as compared to common esophageal cancers (4.0 years), with only one recurrence observed. Conclusion: CC shows an indolent clinical behavior, with a low recurrence rate after radical surgery. The diagnosis of this rare tumor is typically made after surgery. An aggressive approach is required with curative intents.