ALK+ Anaplastic Large Cell Lymphoma With Bladder Involvement Presenting as Fever of Unknown Origin: A Case Report and Literature Review.

Anaplastic large cell lymphoma (ALCL) is a rare malignant tumor normally originating in lymph nodes, though it can occur in extranodal sites. We report a 59-year-old man with anaplastic lymphoma kinase (ALK) positive ALCL involving the bladder diagnosed post-mortem who presented with fever of unknown origin. This is the seventh reported case of ALCL presenting as a bladder neoplasm.