Complete response in a patient with colonic mantle cell lymphoma with multiple lymphomatous polyposis treated with combination chemotherapy using anti-CD20 antibody and cladribine

A 59-year-old woman suspected of having colonic malignant lymphoma was transferred to our hospital (Japan Labour Health and Welfare Organization Tsubame Rosai Hospital, Tsubame, Niigata, Japan) in October 2003. Systemic CT scan showed no swollen lymph nodes. Gallium scintiscan useful in localising lymphoma, showed no abnormal accumulation. Endoscopic findings of the oesophagogastroduodenal tract showed no tumour lesions. Colonoscopic examination was performed in November 2003, and clearly revealed multiple small elevations (fig 1A). Endoscopic mucosal resections were performed on lesions and the resected specimens suggested mantle cell lymphoma (MCL). A second colonoscopic examination performed in July 2004 revealed increased numbers of polyps, indicating a case of multiple lymphomatous polyposis (MLP). Biopsy was performed again to confirm the diagnosis of colonic MCL. Figure 1B–D shows the histopathological findings of both resected and biopsy specimens. Immunohistochemical examination of these specimens revealed positive immunoreactivity for CD20 and CD5 (fig 1E), and negative …