患者男，４８岁。入院前偶然触及左下腹一拳头大小肿物。体检：心肺正常，左下腹隆起，肿物可推动而无压痛。肠鸣音正常，无腰背酸痛。肛门指诊未触及肿物。前列腺二度肿大，质地中等，表面光滑，无压痛。Ｂ超：左下腹探及一３－７ｃｍ×６－５ｃｍ囊状肿物，前列腺中度增大（ Male patient, 48 years old. Before entering the hospital, he accidentally touched a fist mass in the left lower abdomen. Physical examination: Normal heart and lung, left lower abdomen uplift, tumor can be promoted without tenderness. The bowel sounds are normal and there is no low back pain. The anal finger did not touch the mass. The second degree of enlargement of the prostate, medium texture, smooth surface, no tenderness. Ultrasonography: A 3-7cm x 6-5cm cystic mass with a moderately enlarged prostate in the left lower abdomen