To investigate the single-nucleotide polymorphism(SNP) T1151A in the hMLH1 gene in the Chinese, Japanese and German population; the same study was carried out in Chinese colorectal can-cer(CRC) patients; the etiological role of this SNP was explored in three cancers of the G-I tract. Methods:　Genomic DNA was extracted from normal tissues and the specimens were subjected to analysis of the exon 12 of the hMLH1 gene by single strand conformation polymorphism(SSCP), followed by DNA sequencing of aberrant bands in 100 healthy Chinese, 80 healthy Japanese and 100 healthy German individuals, and in 101 Chinese and 109 German CRC patients, in 79 Chinese gastric and 76 Chinese eso-phageal cancer patients, as well as in 79 and 76 first degree relatives of gastric and esophageal cancer patients respectively. Results:　The alleles frequency of T1151A in the hMLH1 gene in Chinese and Japanese healthy individuals are 3% and 2.5% respectively. There was significant difference in the frequency of T1151A in hMLH1 gene between the patients with CRC younger than 45 years and healthy individuals(P<0.05); and between gastric cancer patients with family history, their first degree relatives and heal-thy controls(P<0.05 and P<0.01 respectively). No significant difference was found between esophageal cancer patients, their relatives and healthy controls. This SNP has not been found in German healthy individuals nor in German CRC patients. Conclusions:　The single-nucleotide polymorphism T1151A in the hMLH1 gene might play an etiological role in part of colorectal and gastric cancers in East Asia.

Objective:　To assess the effects of different procedures in the treatment of the primary lesion of rectal cancer associated with liver metastases. Methods:　Retrospective analysis of cases of rectal can-cer with liver metastases admitted from October 1991 to October 1999. Of these 43 patients, 30 were males, 13 were females, age range 33～75 year. The primary lesion of these patients underwent different surgical procedures, including anterior resection in 14 cases, abdominoperineal resection in 11 cases. Hartmann’s operation in 7 cases, and colostomy in 11 cases. Results:　Thirty-one cases of the series died, during the follow-up study, and the median survival time was 13.8, 13.7 and 9.2 months for those undergoing anterior resection, abdominoperineal resection and colostomy respectively. Of the 12 patients who were alive over one year, 2 survived for 8 years. There were no 1-yr survivors among the patients who underwent colostomy. Conclusions:　Aggressive surgical approach for the primary lesion is recommended in cases of rectal cancer associated with liver metastases in order to gain longer survivals.

Objective:　To study the relationship between lymphatic metastasis and extent of radical operation in advanced rectal cancer. Methods:　Seventy-six consecutive cases of rectal cancer subjected to D3 lymphadenectomy were analyzed retrospectively. Lymph nodes were classified as paratumoral regional and at the root of IMA, and for tumors below the peritoneal reflection, lymph nodes(LN) situated in the lateral ligament and mesorectum were examined as well. The metastatic rate was analyzed statistically. Results:　The rate of metastasis was 39.5%, 9.2% and 18.4% in the paratumoral, regional and the root of IMA respectively. The rate of LN metastasis in lesions with distal margin<2cm to the anus was 2.6%, while no metastasis was found in those with distal margin>2.0cm from the anus. The metastatic rate of LNs around the root of IMA was 10.5%. The metastatic rate of LNs in the lateral ligament and in the mesorectum for tumors below the peritoneal reflection were 11.8% and 12.5%. Conclusions:　In advanced rec-tal cancer below the peritoneal reflection, LNs tend to metastasize along the related blood vessels proximally, laterally and to the mesorectum. Extended lateral lymphadenectomy and total mesorectal excision(TME) should be included in cases below the peritoneal reflection.

Objective:　To evaluate and compare the effects of pre- and postoperative radiotherapy on rectal cancer. Methods:　One hundred and seventy-six cases of histologically proved rectal cancer admitted from February 1988 to February 1995, were divided into 3 groups. Group one: 38 patients(T2:68.4%) were treated with a single fraction preoperative radiotherapy, with a tumor dose of 5 Gy; operation was performed within 48 hours. Group two: 43 patients(T3～4:60.5%) were treated by the conventional preoperative radiotherapy regimen with a median tumor dose of 40Gy in 20 fractions, with a daily dose of 1.8～2Gy, followed by surgery within 4 weeks. Group three: 95 patients(T3～4:62.1%,T2～4N＋:81.1%) underwent postoperative radiotherapy with a median tumor dose of 54Gy in 30 fractions, with a daily dose of 1.8Gy, 3～4 weeks after surgery. Results:　The 3-yr and 5-yr survival rates were: 78.9% and 50.0% in group one, 67.4% and 51.1% in group two, 58.9% and 43.1% in group three. Local recurrence rates were:13.1% and 23.6% , 11.6% and 27.9%, 23.1% and 28.4% in the 3 groups, respectively. Only the 3-yr local recurrence rate of the two preoperative radiotherapy groups were significantly lower than those of the postoperative radiotherapy group (P<0.05). Conclusions:　Compared with the postoperative radiotherapy regimen, preoperative radiotherapy with a proper dosage had better local control and fewer complications.

Objective:　To summarize the experience in the management of massive pelvic hemorrhage during radical operations for rectal carcinoma. Methods:　From August 1993 to April 2000, 627 patients underwent radical operations for rectal carcinoma. Massive pelvic hemorrhage occurred in 12 cases, including injury of the presacral venous plexus in 6 cases, of the sacral intervertebral vein in 1 case, of the branches of internal iliac artery or vein in 2 cases, of the common iliac vein in 1 case. Prophylaxis and treatment: The operator should master the anatomy of pelvic cavity, dissect alongside anatomical spaces, protect well the presacral venous plexus, and manage the lateral ligament close to the falciform fascia, medial to the internal iliac artery. If the vagina or the prostate is infiltrated, resection is carried out by cutting and suturing alternatively. If the pelvic wall is slightly involved, branches of the internal iliac artery and/or vein should be ligated while excising the lymph nodes. Hemostatic nail pressing, sponge pressing, blood vessel transfixion-suture, or angiorrhaphy could be used according to the site and the severity of the hemorrhage. Results:　The rate of massive hemorrhage was 1.91% in this series. The amount of bleeding volume was less than 150ml in 5 cases, 150～500ml in 6 cases and >500ml in 1 case. The Miles procedure was performed in 3 cases and sphincter-preserving operations in 6, no mortality occurred during surgery. Conclusions:　Dissection according to anatomy is recommended in order to prevent massive pelvic hemorrhage during radical surgery for rectal carcinoma. Nail pressing, sponge pressing and angiorrhaphy could be selectively used while massive hemorrhage occur.

Objective:　The activity and the clinical mechanism of CuZn-SOD in 86 cases of larger bowel carcinoma patient’s red cells are studied by the author. It is indicated that activity CuZn-SOD in the patients’ red cells is distinctly lower than that of the healthy control and that of the normal Chinese. The disparity showed in the contrast has great significance. The activity of CuZn-SOD in red cells varies with the course. The longer the different pathological and clinical classifications of larger bowel carcinoma patients varies correspondingly. With the pathological changes become severe and the pathological diversifying degree low, the activity slows down respectively. These changes are well displayed by a regular wave- like curve. Nevertheless, no obvious difference is observed in the activity of CuZn-SOD in different patients of different suffering positions.

Objective:　Retrospective analyse the main factors influencing the recurrence of gastric cancer after operation, man attempt to improve the standard of diagnosis and treatment.　Methods: Retrospective analysis was male in 25 cases operated for recurrence of gastric cancer during the period from January 1995 to December 1999.　Results: The recurrences were mainly located in the peritoneal cavity, the lymph nodes and the anatomotic region. Serosal involvement of the lesion, non-radical or irrational extent of lymphatic curage(D≤N) and inadequacy of gastric resection were the main causes of recurrence.　Conclusions: Post-opertive recurrence is closely related to the staging of gastric cancer, the rational extent of operation and the adoption of other therapeutic measures. Early detection and treatment of gastric cancer are most important in reducing recurrence and in improving the prognosis.

To explore the relationship between the uncinate process anglesin CT scanning and the space-occupying lesions of the head of pancreas. Methods: The term uncinate angle is defined as the angle made up of the anterior side and the posterior side of the uncinate process. The uncinate angle was measured in 490 CT pictures which were divided into three groups: Group A, 20 surgically and histopathologically proven cases of space-occupying lesions in the head of pancreas, not diagnosed by CT prior to surgery; Group B, 50 cases of adenocarcinoma in the head of pancreas diagnosed both by CT and histopathology; Group C, 420 cases without presence of any pancreatic lesion. Results: In group C, the mean size of the uncinate angle in 4 levels marked from the lower border upward is 30°±9°、34°±10°、37°±10°、37°±12°、38°±14°and 25°±13°respectively. The angle in cases belonging to group A and group B is significantly wider than that of group C cases(A vs C: 90°±7°vs 47°±9°, t=31.42, P＜0.01; B vs C: 96°±16°vs 47°±9°, t=36.53, P＜0.001). Conclusions: The widening of the uncinate process angle in CT scanning is a sensitive sign suggesting space-occupying lesions in the head of pancreas.

To evaluate the results of pylorus-preservingpancreaticoduodenectomy(PPPD) in the treatment of selected patients with carcinoma of the head of pancreas or of the periampullary region. Methods: From Dec 1984 to Dec 1999, 174 patients with carcinoma of the head of pancreas or of the periampullary region underwent either PPPD(n=47) or standard pancreaticoduodenectomy (PD, n=127); short- and long-term results were compared between the two groups. Results: The incidence of post-operative complications was 34.0% in the PPPD group and 27.6% in the PD group, and the rate of delayed gastric emptying as 8.5% and 6.8%, respectively. There were no significant differences in actuarial survival curves between PPPD and PD, the 5-year survival rate was 47.3% after PPPD and 41.4% after PD. But for patients in stages III and IV, the 5-year survival rate was significantly lower as compared to patients of stages I and II. Conclusions: PPPD might be an acceptable alternative to PD in the treatment of cancer of the head of pancreas or of the periampullary region, if the proximal duodenum or peripyloric lymph nodes were not involved.

To explore the diagnosis and surgical treatment of pancreaticduct obstruction. Methods: Twenty-seven cases of cholangiopancreatical diseases with pancreatic duct obstruction were admitted in our hospital. Among them, eleven cases were chronic pancreatitis, 16 were late stage of pancreatic or peri-ampullary cancer. In the former group, Partington operation was performed to 6 cases; side-to-end pancreato-jejunostomy was carried out to the other 5 cases with stricture in the outlet of the pancreatic duct. For those with malignant diseases, only 5 patients underwent pancreato-jejunostomy. Results: After operation, the symptoms(including abdominal pain and indigestion) were released dramatically in 10 of 15 patients with pancreatitis, compared to those of 5 of 16 patients with malignant diseases. Conclusions: Abdominal pain and indigestion were the common symptoms in cholangio-pancreatical disorders, pancreatic duct hypertension caused by pancreatic duct obstruction is the likely explanation for it. Appropriate operative procedures should be performed to drain the pancreatic duct.