Treatment of Extramedullary Plasmacytoma of the Rectum with Endoscopic Mucosal Resection: A Case Report and Literature Review

Abstract

Purpose Extramedullary plasmacytoma (EMP) is an unusual plasma cell disease.We report a case of EMP arising in the rectum, which is fully removed using endoscopic mucosal resection (EMR).Methods The patient’s clinical, endoscopic, and histologic data were reviewed, as well as the past literature of rectal EMP with a focus on the clinical presentation, treatment and outcome.Results A 64-year-old woman was referred to our hospital with recurrent diarrhea for longer than half a month. She underwent colonoscopy which revealed a polypoid lesion. The lesion was fully excised using EMR, and histopathological examination coupled with immunohistochemistry of the endoscopic biopsy confirmed a primary EMP of the rectum. She did not receive radiotherapy or chemotherapy after being diagnosed with EMP and experienced no recurrence or progression during the 6-month follow-up period.Conclusion Rectal EMP is an extremely rare clinical entity, Only 13 cases have been reported in the English-language literature as far as we know. Clinical suspicion is infrequent owing to its location and nonspecific manifestations. The diagnosis of EMP requires biopsy-proven monoclonal plasma cell infiltration of a single lesion, and the exclusion of multiple myeloma. Although EMP is a highly radiosensitive tumor, endoscopic therapy is increasingly becoming a good option for colorectal EMP when complete endoscopic resection of the tumor is possible. Generally, rectal EMP has an indolent course and the prognosis is favorable, but occasionally it may progress to multiple myeloma, or relapse. Therefore, the patients of EMP should be followed-up for a long time.