Primary ALK-Negative TP63-Rearranged Anaplastic Large Cell Lymphoma in the Bladder: Potential for Misdiagnosis

A 76-year-old gentleman presented with persistent lower urinary tract symptoms. Multiple biopsies, radiological correlation and ancillary studies were required to achieve a diagnosis. The main differential diagnoses lies between urothelial carcinoma and anaplastic large cell lymphoma (ALCL), both of which are known to be positive for p63 and GATA3. An accurate diagnosis is crucial as the management is significantly different. To avoid misdiagnosis a comprehensive immunohistochemistry panel is necessary. Primary bladder lymphomas are rare. Our case represents the first case of primary ALK-negative TP63-rearranged ALCL. We reviewed the literature and discussed the potential pitfalls for misdiagnosis.