Unclassifiable CD20-negative Testicular Diffuse Large B-cell Lymphoma.

CD20-negative diffuse large B-cell lymphoma (DLBCL) is a very uncommon neoplasm, and very rare unclassifiable cases that did not meet the criteria for well-established subtypes of CD20-negative DLBCLs have been reported. CD20-negative DLBCLs often present an aggressive clinical course with important chemoresistance and poor prognosis. Here, we report a case of CD20-negative DLBCL presented as a testicular mass. To the best of our knowledge, this is one of the first reported cases of testicular unclassifiable CD20-negative DLBCL.