Influence of suture physicochemical and surface topographic structure on tumor cell adherence

Local recurrence following curative resection for colorectal cancer may be caused by the seeding of free malignant cells at the anastomotic site. This study investigated the influence of suture material on in vitro tumor cell adherence. Radiolabeled rat colonic cancer cells (RCC5) were incubated with a variety of suture materials, and the relative contribution of chemical composition and physical configuration to cell adherence was assessed. Nonadherent cells were washed free, and the cell adherence was determined by radioactive counting. Marked differences in adherence were observed, with cells preferentially adhering to protein-based and multifilament sutures. These observations were confirmed using scanning electron microscopy. These findings indicate that both chemical composition and physical configuration influence the adherence of tumor cells to sutures and suggest that the use of protein-based and multifilament sutures be carefully considered in situations where free malignant cells may be present following colorectal surgery.This study was supported by a grant from the Joint Research Board of St. Bartholomew's Hospital.The work for this study was carried out at the Department of Surgery, University College Hospital, London, United Kingdom.     

Experimental carcinogenesis at sutured and sutureless colonic anastomoses

This study explores the role of sutures and the healing colonic wound in experimental carcinogenesis. One hundred sixty rats underwent surgery with colotomy and repair using silk, steel, or Vicryl ^® (Ethicon, Somerville, NJ) sutures or a sutureless technique. Forty rats had a sham procedure. All animals received azoxymethane for 12 weeks at a dose of 10 mg/kg/week. Half the rats commenced carcinogen before surgery, and half commenced it eight weeks after surgery. Animals with anastomotic tumors were found in 46 percent of the sham group (P <0.05 cf. sutured), 41 percent of the sutureless group (P <0.02 cf. sutured), and 68 percent of the sutured group. The corresponding figures for anastomotic carcinoma were 9 percent (P <0.001 cf. sutured), 22 percent, and 38 percent. No significant differences in tumor yield were noted among the different sutures. However, several differences were noted between the two carcinogen models. In those animals that received surgery first, there was a higher incidence of anastomotic tumors (P <0.002) and cancers (P <0.0001) in the sutured and sutureless groups, and those tumors that occurred in the sutured group were considerably larger than in those that had carcinogen first (15.9 mm cf. 4.9 mm; P <0.0001). Overall, all sutures seem to enhance anastomotic tumor formation, and we would suggest that a sutureless anastomosis may diminish this risk.     

Cellular proliferation at sutured and sutureless colonic anastomoses

Elevated cellular proliferation in the vicinity of an anastomosis may explain the enhanced susceptibility to carcinogens. The aim of this study was to determine whether anastomotic cellular proliferation was altered by different suture materials and whether a rise in cell turnover also occurred after a sutureless closure. A transverse descending colon enterotomy was repaired with interrupted sutures of 5/0 silk (n=20), stainless steel (n=20), or Vicryl ^® (Ethicon, Inc., Somerville, NJ) (n=20) or by a sutureless technique (n=20). Using a stathmokinetic technique, crypt cell production rates (CCPR) were calculated at the anastomosis and in the adjacent colon at varying intervals between one week and six months after treatment. Overall colonic cellular proliferation appeared to be elevated at a sutured colotomy for at least three months (P<0.05). In contrast, no significant elevation in cellular proliferation was observed at sutureless anastomoses. The duration of elevated proliferative response varied among the sutures.     

Influence of pulsed electromagnetic fields on healing of experimental colonic anastomosis

PURPOSE: The study investigated the influence of pulsed electromagnetic fields (PEMFs) on the mechanical strength and collagen content of uncomplicated colonic anastomosis in rats. METHODS: A standardized left colonic resection was performed 3 cm above the peritoneal reflection, and end-to-end anastomosis was constructed with eight interrupted inverting sutures. Beginning immediately after surgery, randomly assigned groups were exposed to one of the following: 1) 100 Hz (frequency), 1 mT (intensity) PEMFs with 16-hour on/8-hour off cycles (n=8); 2) 100 Hz, 2 mT PEMFs with 16-hour on/8-hour off cycles (n=8); 3) 100 Hz, 1 mT PEMFs with 6-hour on/6-hour off cycles (n=6), whereas the control group (n=10) received no PEMFs. Relaparatomy was performed at 72 hours postoperatively, and the bursting pressure of the anastomotic segment was recorded in situ.The hydroxyproline contents of the anastomotic and adjacent perianastomotic segments of equal lengths were determined. RESULTS: Mean bursting pressure values of the groups that received 100 Hz, 1 or 2 mT PEMFs with 16-hour on/8-hour off cycles (90.88±19.13 and 83.88±7.08 mmHg, respectively) were significantly higher than those of the control group (61.66±10.6 mmHg) and the group with 6-hour on/6-hour off cycles (64.83±7.36 mmHg;P <0.05 for all comparisons). Hydroxyproline contents of the anastomotic and perianastomotic segments were consistently higher in the 16-hour on/8-hour off PEMF groups, compared with those of the corresponding segments of the control group. CONCLUSIONS: PEMFs applied externally to unrestrained rats within a window of PEMF parameters provided a significant gain in the mechanical strength of the colonic anastomosis, at least 72 hours postoperatively. Associated relative increases in the hydroxyproline contents of the (peri)anastomotic colonic segments suggest that an altered collagen metabolism might contribute to this enhancement of the anastomotic repair. Further investigations based on these preliminary data and the definition of the exact measures regarding the effects of PEMFs on biologic systems, in general, may lead to an efficient and new adjunctive modality in colorectal surgery.Suture materials were supplied by Ethicon Limited, Birmingham, United Kingdom.Read at the Third International Congress on New Technology and Advanced Techniques in Surgery, Luxembourg, June 13 to 17, 1995.     

Early local stoma complications in relation to the applied suture material: Comparison between monofilament and multifilament sutures

The frequency and character of early complications following creation of enterostomies, and their relation to the applied suture material, were studied in 50 consecutive patients. The stomas were matured by mucocutaneous eversion and were fixated with Maxon^® (Davis & Geck, Pearl River, NY) 4-0 and Vicryl^® (Ethicon, Inc., Somerville, NJ) 3-0 sutures. Half of the stoma circumference was sutured with one suture type, andvice versa. Three patients died within 10 days. Of the remaining 47 patients, 34 (72 percent) had one or more complications diagnosed. Four (9 percent) suffered major complications (one total stoma loosening and three partial stoma necroses), and 30 (64 percent) had mucocutaneous affections only. There was no statistically significant correlation between enterostomy type or surgical procedure and complications, whereas the incidence of mucocutaneous complications was significantly higher following fixation with Vicryl^® as compared with Maxon^® sutures. The cause of this difference is uncertain; however, the physical configuration of the sutures, Maxon^® being monofilevs. Vicryl ® being braided, seems important. Whether the chemical structure is significant as well remains undetermined at present.     

Role of carcinoembryonic antigen in predicting resectability of recurrent colorectal cancer

The reported low resectability rate for patients with recurrent colorectal cancer who have carcinoembryonic antigen (CEA) levels >11 has led us to perform this study. One hundred twenty-four patients who underwent Radioimmunoguided Surgery ^® (RIGS ^®)procedures for recurrent colorectal cancer from 1986 to the present were studied. In surgery, all patients underwent a traditional exploration followed by survey with a hand-held, gamma-detecting probe to detect preinjected radiolabeled monoclonal antibodies attached to cancer cells. Sites of metastases included: 72 liver (58.1 percent), 23 pelvis (18.5 percent), 15 distant lymph nodes (12.1 percent), 2 anastomotic (1.6 percent), and 12 other sites (9.7 percent). The resectability rate was 43.5 percent (54 patients). The mean preoperative CEA level for patients with resectable disease was significantly lower than for patients with unresectable disease (P=0.017): unresectable—mean, 87.1; SD, 141.0; minimum, 0.3; maximum, 501; resectable—mean, 36.6; SD, 59.3; minimum, 0.3; maximum, 329. The CEA level for patients with liver metastasis did not vary significantly from those patients without metastasis: 70 vs. 58.2 (P=0.58). Those patients with resectable liver tumors had lower mean CEA levels than those with unresectable liver, approaching significance: 41.6 vs. 91.9 (P=0.065). Other metastatic sites had a mean CEA level of: pelvic, 72.6; distant lymph nodes, 47.8; anastomotic, 2.7; and other sites, 53.8. These data suggest that there is a significant difference between the preoperative CEA level of the resectable and unresectable recurrent colorectal cancer patients, but the large standard deviation does not justify abandonment of exploration for any CEA level.Read at the meeting of The American Society of Colon and Rectal Surgeons, San Francisco, California, June 7 to 12, 1992.     

Prospective,randomized trial of inpatientvs. outpatient bowel preparation for elective colorectal surgery

A prospective, randomized trial of inpatientvs. outpatient bowel preparation for elective colorectal surgery was performed in 100 consecutive patients. Bowel preparation was standardized for both groups and consisted of 4 liters of Colyte^® (Reed & Carnrick, Piscataway, NJ) and oral neomycin and Flagyl^® (G. D. Searle & Co., Skokie, IL) the day before surgery. Patients were randomized into four subcategories: ileocolostomy, colocolostomy, abdominal perineal resection, and other. Tap water enemas were administered on the morning of surgery to ensure an adequate mechanical preparation. Ninety-six percent of the inpatient group and 97 percent of the outpatient group were able to drink three-fourths or more of the oral lavage preparation (P=0.789, Fisher's exact text). A mean of 2.26 tap water enemas was required to achieve clear returns for the inpatient group, compared with 2.28 tap water enemas for the outpatient group (P=0.221, Fisher's exact test). The adequacy of the bowel preparation as graded by the primary surgeon was good (84 percent), fair (12 percent), and poor (4 percent) in the outpatient group (P=0.673, Fisher's exact test). Wound infection developed in 4 percent of the inpatient group and 4 percent of the outpatient group (P=1.0, Fisher's exact test). Anastomotic leak or intra-abdominal abscess was seen in one patient in each group (P=1.0, Fisher's exact test). We conclude that outpatient bowel preparation is as effective as inpatient bowel preparation for elective colorectal surgery and offers the advantage of cost savings and shorter hospitalization.     

Valtrac®-secured intracolonic bypass device

PURPOSE: The intracolonic bypass tube has been used both experimentally and clinically to protect the anastomotic site. A newly designed intracolonic bypass, the Valtrac ^® -secured intracolonic bypass, which consisted of a biofragmentable anastomosis ring (BAR) and was connected with a soft, thin vinyl tube, was used in the colon approximately 5 to 10 cm proximal to the anastomotic site. The distal end of the vinyl tube is passed through the colonic anastomosis to the anus to bypass the fecal stream. METHODS: Eighteen piglets were divided into three groups of six each. Group A piglets underwent colon resection and rough anastomosis with large gaps between sutures, followed by Valtrac ^® -secured intracolonic bypass. Group B piglets underwent the same procedures, but a colonic outlet obstruction also was done with pursestring sutures tied over the anus. Group C piglets underwent colon resection and rough anastomosis, but no intracolonic bypass tube was inserted (as in the control group). RESULTS: All Group A and Group B piglets survived. Passage of the BARs occurred approximately two weeks later. As the barium enema passed through the bypass tube, it showed a patent BAR-secured tube and intact anastomosis with no leakage. In Group C, anastomotic leakage occurred in four of six piglets, three of which died. Barium enema showed leakage at the anastomotic site. CONCLUSIONS: In the animal model we used, our new intracolonic bypass device proved to be a simple, safe, reliable means of protecting the anastomotic site and, thereby, eliminated the need for a diverting colostomy. Still we need further steps to test its potential in clinical use.Presented at the meeting of the Society of Colon and Rectal Surgeons, Republic of China, Taipei, Taiwan, December 15, 1996.     

Does a proximal colostomy affect colorectal anastomotic healing?

Fecal diversion has been implicated as an etiologic factor in anastomotic stenosis following colorectal surgery, particularly following the use of circular anastomotic stapling devices. However, experimental confirmation of the effects of fecal diversion on anastomotic healing is virtually nonexistent. The purpose of this study was to serially evaluate colorectal anastomotic healing with proximal colostomy (COL) and without it (CON; control) using two anastomotic techniques in a porcine model. Fifty-two (28 CON; 24 COL) mixed-breed female pigs had colorectal anastomoses using either a two-layer handsewn (HS) or an EFA ^® (U.S. Surgical Corporation, Norwalk, CT) circular stapled (CS) technique. Anastomotic blood flow was measured using laser Doppler velocimetry (LDV). At second surgery (5, 11, 60, or 120 days post-operatively), the following data were collected: repeat LDV, gross and microscopic anastomotic inflammatory scores, anastomotic diameter, and bursting pressure. There were no significant differences in anastomotic blood flow (LDV), inflammatory scores, or incidence of leak or stenosis between the CON and COL groups or between anastomotic techniques. Bursting pressure was significantly lower for the COL group at day 11 but not any other postoperative day (POD). Proximal colostomy does not appear to exert adverse effects on colorectal anastomotic healing. The choice of colorectal anastomotic technique should not be influenced by the need for proximal colostomy.Read at the meeting of The American Society of Colon and Rectal Surgeons, St. Louis, Missouri, April 29 to May 4, 1990.Winner of the Ohio Valley Colon and Rectal Surgeons Award.     

Randomized,controlled study on adjuvant immunochemotherapy with PSK® in curatively resected colorectal cancer

A randomized, controlled trial of adjuvant immunochemotherapy with PSK ^® (Kureha Chemical Industry Co., Tokyo, Japan) in curatively resected colorectal cancer was studied in 35 institutions in the Kanagawa prefecture. From March 1985 to February 1987, 462 patients were registered. Four hundred forty-eight of those patients (97.0 percent) satisfied the eligibility criteria. The control group received mitomycin C intravenously on the day of and the day after surgery, followed by oral 5-fluorouracil (5-FU) administration for over six months. The PSK ^® group received PSK ^® orally for over three years, in addition to mitomycin C and 5-FU as in the control group. At the end of February 1990, the median follow-up time for this study was four years (range, three to five years). The disease-free survival curve and the survival curve of the PSK ^® group were better than those of the control group, and differences between the two groups were statistically significant (disease-free survival,P =0.013; survival,P =0.013). These results indicate that adjuvant immunochemotherapy with PSK ^® was beneficial for curatively resected colorectal cancer.Dr. Suzuki is deceased.     

Hydrostatic balloon dilatation of benign colonic anastomotic strictures

From 1985 to 1990, 25 patients with benign colorectal anastomotic strictures were treated. The majority of the patients presented with decreasing stool caliber and abdominal cramps. Most of the strictures were secondary to anastomosis utilizing the EEA^® stapling device (United States Surgical Corp., Norwalk, CT) for malignant neoplasm. Under IV sedation, strictures were dilated endoscopically with the TTS^® balloon (Microvasive). No complications were encountered in this series. Hydrostatic balloon dilatation is a safe and effective modality for treatment of anastomotic strictures.     

Fibrin glue improves the healing of irradiated bowel anastomoses

Many surgeons are reluctant to construct a bowel anastomosis with irradiated intestine. Previous studies have demonstrated diminished tensile strength of rat small bowel anastomoses that have been irradiated intraoperatively. To determine whether fibrin glue, a known tissue adhesive, improves the healing of these anastomoses, 69 male Sprague-Dawley rats were randomized into three anastomotic groups: Group 1, sutured ileal anastomosis without radiation or fibrin glue; Group 2, irradiated sutured ileal anastomosis without fibrin glue; and Group 3, irradiated ileal anastomosis with fibrin glue added to the suture line. Groups 2 and 3 received a single dose of 2,000 R intraoperatively. At seven days, the rats were sacrificed and the anastomotic segment was tested for breaking (tensile) strength. Anastomotic collagen content was evaluated using a hydroxyproline assay. Tensile strength results demonstrated that Group 2 was significantly weaker than Groups 1 and 3 (P=0.001) and that the hydroxyproline content of Group 3 was significantly greater than that of Group 2 (P=0.015). These results show that the addition of fibrin glue to an intraoperatively irradiated small bowel anastomosis improves healing, as demonstrated by both tensile strength and hydroxyproline content studies.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991.This work was supported in part by the Bowman Research Fund.     

Efficacy of radioprotective agents in preventing small and large bowel radiation injury

PURPOSE: A variety of adjuvant treatments and cytoprotective agents have been proposed to lessen the toxicity of radiation therapy. The following study was designed to evaluate the benefit of six agents or combinations using anastomotic bursting strength as a measure of transmural radiation injury. METHODS: The 40-Gy study consisted of the following. Seventy-two male Sprague-Dawley rats were divided into eight equal groups: nonradiated control, radiated untreated control, and six radiated treated groups. The radioprotective treatments included ribose-cysteine (RibCys), WR-2721, glutamine, vitamin E, MgCl₂/adenosine triphosphate, and RibCys/glutamine in combination. Radiated animals received 40 Gy to the abdomen. Two weeks after radiation, all animals underwent small bowel and colonic resection with primary anastomosis. Animals were sacrificed one week postoperatively, at which time anastomoses were evaluated and bursting strengths determined. The 70-Gy study consisted of the following. The same protocol was repeated for five groups of nine rats divided into nonradiated, radiated untreated, and three radiated treated groups receiving RibCys (8 mmol/kg), RibCys (20 mmol/kg), and WR-2721. All radiated animals received 70-Gy doses. RESULTS: In the 40-Gy group, there were 10 radiation-related deaths and 6 anastomotic leaks among 70 rats studied. None of the differences between groups were significant. Nonradiated control group small bowel and large bowel anastomotic bursting pressures were significantly elevated compared with all radiated groups. Compared with radiated controls, there were significant improvements in small bowel bursting strength in the RibCys, WR-2721, RibCys-glutamine, and vitamin E groups and significant improvement in colonic bursting strength in MgCl₂/adenosine triphosphate, WR-2721, and RibCys groups. In the 70-Gy group, all nine nonradiated control rats survived. All eight untreated radiated control rats died, four of eight WR-2721 animals died (P=0.03), all RibCys (8 mmol/kg) animals died (P=0.03), and three of nine treated with RibCys (20 mmol/kg) survived (P=0.08). CONCLUSIONS: WR-2721 and RibCys gave consistent protection against large and small bowel radiation injury. The lower incidence of treatment-related toxicity and potentially equal or greater radioprotective effects may make RibCys more clinically useful than WR-2721.Supported by the 1993 ASCRS/ETHICON Surgical Research Fellowship Award and the Minneapolis Medical Research Foundation. Read at the meeting of The American Society of Colon and Rectal Surgeons, Orlando, Florida, May 8 to 13, 1994.     

Improvements in mechanical bowel preparation for elective colorectal surgery

PURPOSE: This study was undertaken to determine whether a mechanical bowel preparation with 2 liters of polyethylene glycol solution combined with a laxative (Group A) increases the acceptability of bowel preparation and reduces discomfort compared with 4 liters of polyethylene glycol solution (Group B). METHODS: One hundred patients undergoing an elective colorectal resection were included in a prospective, randomized study. Acceptability (nausea, vomiting, abdominal cramps, discomfort from insertion of the nasogastric tube, and anal discomfort) was assessed using visual analog scales. Efficacy of bowel lavage was scored intraoperatively by a blinded surgeon. RESULTS: Overall acceptability was 5.1±2.8 in Group A patients and 5.6±2.6 in Group B patients ( P =0.5). The incidence and visual analog score for nausea, vomiting, anal discomfort, and cramps were not different between groups. Excellent efficacy of bowel preparation was shown in 94 percent of patients in Group A and 84 percent of patients in Group B ( P =0.5). The incidence of septic complications was 2 percent in Group A patients and 12 percent in Group B patients ( P =0.06). CONCLUSION: Because the acceptability of both cleansing regimens were not different, 2 liters of polyethylene glycol plus Prepacol ^® should be preferred because the amount of fluid administered to clean the bowel is reduced and the nasogastric tube can always be avoided.Presented in part at the meeting of the Academy of Surgical Research, Münster, Germany, October 3 to 5, 1996.     

First sutureless closure of a colotomy: Short-term results of experimental laser anastomosis of the colon

To assess the possibility of laser anastomosis of the colon, experimental laser closure of colotomies was performed. Transverse colotomies (average 20.7 mm) in New Zealand white rabbits (n = 20) were closed with a 1,064-nm Nd:YAG laser at a pulsating 0.5-W wave of power, using guy sutures to approximate the tissue edges. The laser energy was applied through a specially designed hand piece and hand-held 600- m gas-cooled noncontact quartz fiber to produce a satisfactory tissue welding. Similar colotomies were closed using a single layer of interrupted sutures of 5–0 Maxon ^® (Davis & Geck, Pearl River, NY) in a control group (n=20). Bursting pressure and index of narrowing were recorded immediately after anastomosis and at 1, 4, and 7 days following surgery. Bursting pressure of the laser-welded closure at 1 day was significantly lower than that of the sutured controls (P <0.01); however, all rabbits recovered uneventfully. There was a marked decrease in adhesion formation following laser anastomosis (P < 0.05). Conversely, one control rabbit showed functional stenosis at 4 days. Histologic study revealed an accelerated healing in the laser group. The index of narrowing was significantly higher in the laser group than in the control group (P <0.05). The completely water-sealed laser anastomosis reduces adhesions and is comparable to conventional suture anastomosis of the colon.This work was supported by private sources (Colorectal Service), by the Colorectal Unit Research Fund, and by a research grant from St. Vincent's Hospital.     

What happens to the Valtrac® anastomosis of the colon?

Late results after colonic anastomoses performed with the biofragmentable anastomosis ring (BAR; Valtrac ^®; Davis & Geck, Wayne, NJ) were evaluated in 30 patients who had undergone a left-sided colonic or rectosigmoid anastomosis a mean of 24.5 (range, 12–38) months earlier. Patients were asked about their late postoperative recovery and their bowel habits. A barium enema was performed, and then a flexible endoscopy was done, during which the anastomotic area was evaluated both in macroscopic terms and histologically. One of the patients had died, and three refused to participate in the investigation. Of the remaining 26 patients, one had been reoperated on 22 months after the primary sigmoid resection. The reason for reoperation was an anastomotic stricture. One of the patients was admitted to the hospital during the study and was operated on for reasons not related to the anastomosis. Twenty-four patients underwent the study scheme. All had recovered uneventfully. Sixteen anastomoses could not be identified radiologically and seven not even during endoscopy. Histologically, there was mild-to-moderate fibrosis and scarring in 17 anastomoses, and, in the seven that could not be identified, only normal colonic mucosa was found. The late results of BAR anastomoses are satisfying, and the rate of complications is acceptable.     

Aseptic colon resection by an invagination technique

A new aseptic colon resection by an invagination technique is presented. The bowel to be resected is invaginated down into the healthy intestine, and the anastomosis is sutured in one layer of continuous suture before transection by a diathermy wire, placed in the intestinal lumen via the anus. Sections of bowel that cannot be invaginated,e.g.,because of a tumor, are first removed by transection between pairs of cable ties, which close the lumen. Twenty dogs were operated on without receiving prophylactic antibiotics. In 10, the intestine was transected between cable ties. An imprint, taken from the anastomosis and subcutis, was cultured. The bacterial count at the anastomosis exceeded 100 in only three cases; in the subcutis, this was the case in one dog. One wound infection developed. Serial barium enemas at 1, 2, 3, and 4 weeks revealed no anastomotic leakage. One early death because of a total anastomotic dehiscence was encountered, and two dogs were killed because of wound dehiscence and anastomotic stricture, respectively. It is concluded that, in dogs, the method is easily and safely performed, but further experimental studies are needed.This study was supported with grants from Fonden til Laegevidenskabens Fremme, Kraeftens Bekaempelse, Sygekassernes Helsefond, and Aarhus Universitets Forskningsfond.     

Stapled colonic J-pouch-anal anastomosis without a diverting colostomy for rectal carcinoma

PURPOSE: Colonic J-pouch reconstruction is designed to improve functional outcome of coloanal anastomosis. Most surgeons use a diverting colostomy to avoid severe pelvic sepsis caused by anastomotic breakdown. METHODS: We report the outcome of 30 consecutive patients with colonic J-pouch-anal anastomosis without a diverting colostomy performed between November 1992 and October 1993. All patients had carcinoma of the lower two-thirds of the rectum. Patients were seen every three months. Functional results were compared with those of 21 rectal cancer patients with straight coloanal anastomosis who underwent surgery in the same period and 20 normal patients. RESULTS: There were two anastomotic leakages and one postoperative death. After one year, patients with pouch anastomosis had significantly less frequency of defecation and rectal urgency compared with those with straight anastomosis (P <0.01); 48 percent of patients with straight anastomosis had more than five bowel movements per day, whereas all patients with pouch anastomosis had five or less bowel movements per day. Manometric studies showed maximum tolerable volume was significantly higher in patients with pouch anastomosis (81 vs. 152 ml;P <0.01). CONCLUSIONS: Stapled colonic J-pouch-anal anastomosis without a diverting colostomy is a reliable procedure that provides good, long-term functional results.Supported by National Science Council, Taiwan, Research Grant NSC 83-0412-B182-021.Read at the meeting of the International Society of University Colon and Rectal Surgeons, Singapore, Singapore, July 2 to 6, 1994.     

Restorative proctocolectomy in patients older than fifty years

PURPOSE: This study was undertaken to compare functional results, complications, preoperative durations of disease, and rates of dysplasia and neoplasia between older and younger chronic ulcerative colitis patients undergoing restorative proctocolectomy (RPC) with mucosectomy. METHODS: A total of 392 patients with a preoperative diagnosis of chronic ulcerative colitis underwent elective RPC with mucosection and handsewn ileoanal anastomosis. Pathologic reports were reviewed, with specific reference to findings of dysplasia or cancer. Functional results concerning the number of bowel movements per 24 hour period and the incidence of fecal soilage were obtained by direct or telephone patient interview. FINDINGS: Group I consisted of 326 patients aged 5 to 49 (mean, 30.9) years and 160 women. Group II comprised 66 patients aged 50 to 74 (mean, 56.9) years and 29 women. Duration of disease was significantly longer in the older group (6.2 vs. 15.6 years;P <0.001). The older group had significantly higher rates of dysplasia (29/326 vs. 19/66;P <0.0001) and malignancy (14/326 vs. 9/66;P =0.003). Rates of complication, hospital days following RPC, and total hospital days for all causes were comparable between groups. Perfect daytime continence was observed in 81.6 percent of Group I and 80 percent of Group II patients (213/261 vs. 40/50;P = 0.79). Perfect continence during sleep was observed in 65.1 percent of Group I and 62 percent of Group II patients (170/261 vs. 31/50;P =0.67). Mean number of bowel movements per 24 hour period for Group I was 6.3±0.2 and for Group II was 7.4±0.5. Mean difference, one movement per 24 hours, was not significant (95 percent confidence interval, –0.02 to 2.1;t =1.95,P =0.055). CONCLUSIONS: We conclude that patients older than 50 years are suitable candidates for RPC with mucosectomy. Functional results and complication rates are similar to those observed among younger patients. Patients older than 50 years have a significantly higher rate of concurrent dysplasia and malignant degeneration than younger patients, most probably because of a longer duration of disease. RPC with mucosal excision potentially lowers this risk by elimination of all colorectal mucosa.Read at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996, and at the Tripartite Meeting, London, United Kingdom, July 8 to 10, 1996.     

Pathogenetic implications of DNA nondiploidy in colorectal cancers

PURPOSE: Several studies propose that proximal and distal colorectal cancers have a different pathogenesis. We tested the hypothesis using flow cytometric DNA analysis. METHODS: DNA analysis was performed in 719 patients with colorectal cancer. In addition, histopathologic data were re-evaluated in a blinded fashion by a single pathologist. RESULTS: Distal tumors were more often nondiploid than were proximal tumors (61 vs.49 percent;P =0.015). Compared with the proximal tumor, distal tumors were smaller ( P =0.0001) and had less desmoplastic reaction (39 vs.53 percent;P =0.0001). Tumor location had no significant associations with the remaining parameters, including mucin production, perineural invasion, blood/lymphatic vessel invasion, lymphocytic infiltration, histologic grade, tumor stage, gross appearance, age, and gender. CONCLUSIONS: The unequal distribution of ploidy suggests distinct pathogenetic mechanisms at proximal and distal sites.Poster presentation at the meeting of The American Society of Colon and Rectal Surgeons, Seattle, Washington, June 9 to 14, 1996.