Chronic lymphocytic leukemia/small lymphocytic lymphoma arising in the pituitary gland: illustrative case.

backgroundThe authors describe a 60-year-old female who underwent a correlative examination for an accidental scalp injury, revealing a sellar mass, which was surgically excised and pathologically confirmed to be a non-Hodgkin's small B-cell lymphoma. These findings in combination with the immunophenotype led to a final diagnosis of chronic lymphocytic leukemia/small lymphocytic lymphoma. Previous studies have shown that hematological solid tumors occurring in the pituitary gland are extremely rare, and there are only approximately three other cases of living patients with similarities to this case, all of which had ambiguous expression of subsequent hematological treatment. OBSERVATIONS: In this case, the authors used an endoscopic approach to completely excise the tumor. Follow-up of the patient was continued after surgery, and the patient is currently receiving standardized treatment with zanubrutinib. LESSONS: This patient did not have any previous history of tumor, had a good postoperative recovery with a normal quality of life, and still receives hormone replacement and zanubrutinib on a standardized basis. This is a complete case that has not been previously reported and reveals the diagnostic and therapeutic process of rare diseases in the sellar area.