High grade non-germinal centre-like diffuse large B-cell lymphoma double expressor presenting as a hydrocoele.

A 72-year-old man was referred to our urology outpatient department with a left hemi-scrotal swelling increasing in size over a matter of weeks, initially suspicious for a left hydrocoele. Initial investigation with ultrasound (US) identified a heterogenous enlargement of the left testis and epididymis with a soft tissue mass extending through the inguinal canal. Subsequent CT detected this soft tissue mass to extend along the left gonadal vein to the level of the left renal vein. A biopsy of the retroperitoneal mass confirmed a diagnosis of diffuse large B-cell lymphoma. Immunohistochemical staining further categorised this lymphoma as double expressor but not double hit.Through multidisciplinary team involvement the patient was treated with combination steroids and chemotherapy. Given the scrotal involvement this was considered a sanctuary site for chemotherapy therefore the patient also received radiotherapy to the scrotum. He recovered well following his treatment. This case highlights how early specialist referral can identify rare variants of disease. Essential preoperative imaging with US prior to treating a presumed hydrocoele prevented inappropriate surgical excision. A multidisciplinary team approach improved the patient's outcome and is hoped to have improved his chances of recurrence-free survival.