ALK + anaplastic large cell lymphoma involving the bladder: case report and review of the literature.

We reported a case of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALK + ALCL) involving the bladder. The patient was a 27-year-old female, whose main clinical symptoms included fever, painless lymphadenopathy, and hematuria. Imaging studies suggested a bladder mass. The bladder mass was maximally resected through transurethral bladder tumor resection. The pathology report indicated a malignant tumor of the bladder. Based on immunohistochemical and gene rearrangement results, the diagnosis was confirmed as ALK + ALCL. After undergoing five cycles of treatment with the BV + CHP chemotherapy regimen, the patient's condition is currently stable, and no tumor recurrence was observed upon re-examination. ALK + ALCL involving the bladder is very rare, and early diagnosis is challenging. By reviewing the diagnostic and treatment process of this patient, and in conjunction with a review of modern literature on the disease's incidence characteristics, treatment protocols, and prognosis, this aims to provide a reference for clinicians in diagnosing and treating this condition, thereby reducing delays.