患者男,30岁,农民.因脓血便、消瘦三月入院.自幼体弱多病,哭声尖细,发育及智商差于同龄儿.已婚,育有一男孩,聪明,体健;父母非近亲结婚,家族中无类似病例,一舅患肝癌两年前病逝.体检:表情刻板,瓮声,对答切题、缓慢,下颌宽大,双耳大而外翻,嘴大唇厚,面容及行为给人以痴傻印象,智力低下,双侧睾丸稍大,扁平足;肛诊:距肛门齿线以上9～14cm触及一肿块,质硬,压痛.外周血淋巴细胞培养:染色体核型G显带,分析为46,fra(x)(q~(27)Y,fra(1)(q~(21)).诊断为:1.直肠癌进展期,2.脆性X综合征.术中见肿瘤侵犯直肠浆膜,但肠系膜和瘤周未见明显肿大淋巴结,无局部粘连及远处转移,行Dixon根治术.术后病理报告直肠溃疡型低分化印戒细胞癌.侵及浆膜,局部淋巴结转移,同时送实体瘤行癌细胞培养染色体分析,因细胞过熟未获得可供分析 The patient was male, 30 years old, farmer. He was admitted to hospital in March because of bloody stools and wasted. He was weak and sick since childhood. He had a cry, development and IQ worse than that of his peers. He was married, had a boy, was smart, healthy, and his parents were not close relatives. There was no similar case in the family. One patient died of liver cancer two years ago. Physical examination: Stereotypical expression, squeaking, answering the question, slow, wide jaw, big ears and valgus, thick lips, face and behavior. Silly impression, mental retardation, bilateral testicles slightly larger, flat feet; anal diagnosis: 9 to 14 cm above the anal tooth line touched a mass, hard, tenderness. Peripheral blood lymphocyte culture: chromosome karyotype G band, analyzed as 46,fra(x)(q~(27)Y,fra(1)(q~(21)). Diagnosis is: 1. Progression of rectal cancer, 2. Fragile X syndrome, Invasion of rectal cancer Membrane, but no obvious enlarged lymph nodes, no local adhesions and distant metastases, Dixon radical resection. Postoperative pathology reports rectal ulcer type poorly differentiated signet ring cell carcinoma. Invasion of the serosa, regional lymph node metastasis, Simultaneous delivery of solid tumors for chromosome analysis of cancer cell cultures, due to over-matured cells not available for analysis