Helicobacter pylori seroprevalence and colorectal neoplasia: evidence against an association.
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Biomedical subjects
Publications and source records attributed to K A Forde.
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Plasma levels of p53 protein were examined by an enzyme linked immunosorbent assay in 184 patients enrolled in a colonoscopy study. The mean levels among 47 individuals with normal colonoscopic examinations and no prior history of colonic neoplasia (0.12 ng/ml) and among 61 individuals with normal colonoscopic examinations and a prior history of colonic neoplasia (0.09 ng/ml) were similar. However, the mean levels among 54 individuals with newly diagnosed colonic adenomas (0.44 ng/ml) and 22 individuals with newly diagnosed colonic carcinomas (0.55 ng/ml) were statistically significantly elevated compared to the normal controls (P < 0.02). Among these tumor patients, the plasma levels tended to increase with increasing adenoma size and with increasing carcinoma stage, although these trends were not statistically significant. Defining a significant positive plasma level as any value greater than ten times background, the percentage of positive samples increased from 4% in the controls to 20% in the adenoma cases to 32% in the carcinoma cases. These results demonstrate that plasma p53 protein levels are elevated in a subgroup of individuals with colonic neoplasia.
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PURPOSE: This study was designed to determine whether patients with coronary artery disease are at elevated risk for colorectal neoplasia. METHODS: A case-control study was conducted among consecutive patients in three colonoscopy practices in New York City from 1986 to 1988. All study participants completed an interview questionnaire covering demographics, diet, environmental and behavioral exposures, family and personal medical history, and other variables. For the present study, 298 newly diagnosed colorectal adenoma cases and 107 incident cancer cases were compared with 507 colonoscoped controls without colorectal neoplasia or other significant findings on colonoscopy. Data on history of coronary artery disease (angina and/or heart attack) were obtained solely from the study participants' questionnaire responses. RESULTS: No association was observed between angina, heart attack, or either and colorectal adenomas in males. However, prior coronary artery disease was found to be associated with colorectal cancer in males more than 60 years of age and with colorectal adenomas in females aged 50 years or younger. CONCLUSION: Men with coronary artery disease may be at elevated risk for subsequent colorectal cancer. Young women with coronary artery disease also may be at elevated risk for colorectal neoplasia.
Although there is a known reciprocal association between breast and colorectal cancer in women, few studies have investigated whether a similar association exists between breast cancer and colorectal adenomatous polyps, known to be precursor lesions for colon cancer. A case-control study was conducted on patients in three colonoscopy practices in New York to determine possible risk factors for adenomatous polyps. Among women studied, there were 128 patients with incident adenomatous polyps and 284 control subjects who underwent colonoscopy and had no colorectal neoplasia. No significant association between the incidence of an adenomatous polyp in the colon or rectum and a history of breast cancer was found (odds ratio, 0.71; 95% confidence interval, 0.34 to 1.64). If shared risk factors for breast and colorectal cancer are the reasons for the concurrence of these two malignant lesions, these results suggest that these factors act at the level of promoting adenomatous polyps of the colon and rectum into colorectal cancer.
Individuals with a family history of colorectal cancer are believed to be at an increased risk of developing colorectal neoplasia. To estimate this risk and the potential yield of screening colonoscopy in this population, we recruited and prospectively colonoscoped 181 asymptomatic first-degree relatives (FDR) of colorectal cancer patients and 83 asymptomatic controls (without a family history of colorectal cancer). The mean ages for the FDR and control groups were 48.2 +/- 12.5 and 54.8 +/- 11.0, respectively. Adenomatous polyps were detected in 14.4 percent of FDRs and 8.4 percent of controls. Although 92 percent of our FDRs had only one FDR afflicted with colon cancer, those subjects with two or more afflicted FDRs had an even higher risk of developing colonic adenomas (23.8 percent) than those with only one afflicted FDR (13.1 percent). A greater proportion of adenomas was found to be beyond the reach of flexible sigmoidoscopy in the FDR group than in the controls (48 percent vs. 25 percent, respectively). Logistic regression analysis revealed that age, male sex, and FDR status were independent risk factors for the presence of colonic adenomatous polyps (RR = 2.32, 2.86, and 3.49, respectively; P less than 0.001). Those at greatest risk for harboring an asymptomatic colonic adenoma are male FDRs over the age of 50 (40 percent vs. 20 percent for age-matched male controls). Based on probability curves, males with one FDR afflicted with colon cancer appear to have an increased risk of developing a colonic adenoma beginning at 40 years of age. Our results document, for the first time, an increased prevalence of colonoscopically detectable adenomas in asymptomatic first-degree relatives of colon cancer patients, as compared with asymptomatic controls, and support the use of colonoscopy as a routine screening tool in this high-risk group.
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Multiple studies have suggested a possible relationship between prior cholecystectomy and the occurrence of subsequent colorectal carcinoma. This relationship has been particularly noticed among female patients and for right-sided lesions of the colon. In the current study, the authors undertook a case-control study among patients who underwent colonoscopy in three private practices in New York City between April 1986 and March 1988. Over this period, 302 adenomatous polyp cases, 106 colon cancer cases, and 507 controls were interviewed regarding their prior history of cholecystectomy. Overall, no significant association was observed between cholecystectomy and either colorectal adenomatous polyps or cancer. Cholecystectomy does not appear to be a significant risk factor for colorectal neoplasia.
Obesity has been investigated as a risk factor for various malignancies, including colon cancer. A case-control study was conducted on patients in three colonoscopy practices in New York City to determine possible risk factors for colorectal adenomatous polyps, a known precursor lesion for most cases of colorectal cancer. Among 301 case subjects with incidence adenomatous polyps (174 men and 127 women) and 506 control subjects (223 men and 283 women), an increased risk was observed with increasing body mass index in women (odds ratio 2.1, 95% confidence interval 1.1-4.0; for highest versus lowest quartile, linear trend P = .02). A nonsignificant trend was observed for men. The increased risk seen in women is consistent with prior observations regarding reproductive hormonal and dietary risk factors for colorectal cancer.
A 41-year-old woman with recurrent attacks of postprandial abdominal pain was found on endoscopic retrograde cholangiopancreatography and subsequent computed tomographic scan to have an enteric duplication within the substance of the pancreas with communication to the pancreatic duct. Celiotomy demonstrated a noncontiguous gastric duplication cyst. Internal drainage was curative.
Our previous work on protein kinase C (PKC) and colon cancer has shown altered levels of PKC activity in human colon tumors, as well as activation of PKC by colon tumor promoters such as bile acids. To understand further the role of PKC in colon carcinogenesis, we analyzed the expression of phorbin, a gene induced by PKC activation, in a series of different stages of human colon tumors. As shown by northern blot analyses of poly (A)+ RNA, higher levels of phorbin RNA were seen in 26 colon tumor samples than in their adjacent normal colonic mucosa. There also appeared to be a correlation between the abundance of phorbin RNA in the tumors and the extent of invasion (tumor-to-normal tissue phorbin RNA ratio = 4.2, 8.0, and 11.9 for Dukes' A, B, and C, respectively). Phorbin RNA was also abundant in a human colon cancer line (HT29). We also examined the expression of other mitogen-responsive genes (c-myc, ODC, and beta-actin) in a set of 19 colon tumor samples. All tumors displayed significant (mean 3.8-fold) increases in the level of c-myc RNA compared with their adjacent normal colonic mucosa. About 47% and 16% of these tumor samples also showed increased levels of ODC (mean 3.1-fold) and beta-actin (mean 1.6-fold) RNA, respectively. The increased levels of c-myc, ODC, and beta-actin RNA did not correlate with the extent of tumor invasion. Taken together, these results demonstrate that human colon tumors usually display increased levels of both phorbin and c-myc RNAs. The marked increases in phorbin RNA suggest that this could serve as a useful biomarker in studies on human colon cancer.
Leakage from colonic anastomoses is a common cause of morbidity in patients recovering from bowel surgery. We evaluated a technique of laser-fibrinogen reinforcement to strengthen colonic anastomoses in a canine model. After creation of eight single-layer interrupted suture anastomoses in six dogs, indocyanine green-dye-enhanced fibrinogen was topically applied to the serosal surface and exposed to 808 nm diode laser energy. Immediately following colonic anastomosis, the mean leakage pressure was 137 +/- 22 mm Hg in the group (n = 8) using sutures alone and 326 +/- 67 mm Hg (P less than 0.001) in the group (n = 8) after the sutured anastomosis was reinforced with lasered-fibrinogen. On histological examination, no evidence of thermal injury to the tissue edges was noted and a layer of fibrinogen bridged the anastomotic gap. Laser dye-enhanced fibrinogen reinforcement significantly enhances the strength of sutured colonic anastomoses without causing appreciable thermal injury to the host tissues.
A 10-year review of our experience with all patients with symptoms of colonic narrowing (n = 61) revealed 14 patients who were treated endoscopically. The site of narrowing was the sigmoid colon in 12 patients and the rectum in two patients. The strictures occurred after anastomosis in seven patients, with carcinoma in four patients, and with inflammatory disease, external compression, and idiopathy in one patient each. Although combinations of endoscopic techniques were occasionally used, the predominant method responsible for successful management of the narrowing was bouginage in four patients, endoscopy with a prototype dilating endoscope in four patients, balloon dilatation in three patients, and electrocautery and laser surgery in one patient each. There were no perforations or bleeding complications. Repeated treatments were usually needed. As less invasive methods evolve to treat colonic narrowing, appropriate matching of available techniques with the underlying disease becomes easier. We have found that dilation with a bougie, balloon, or a prototype dilating endoscope can provide especially beneficial results when used on patients with strictures resulting from inflammatory disease or external compression. Cutting and ablating tools such as the electrocautery and laser tools are more suited for management of strictures that result from carcinoma and anastomotic webs. Appropriate matching of endoscopic technique to underlying colonic pathology will allow increasingly successful and safer management of colonic narrowing without operation.
Analysis of relative polyp locations in 426 consecutive patients with multiple colonic polyps found on colonoscopy showed novel findings. First, synchronous and metachronous neoplastic polyps showed spatial clustering in individual patients. For example, patients with their largest neoplasm in the cecum or proximal ascending colon, had 34.3 percent +/- 4.6 percent (standard error) of their other colonic neoplasms in the same location. Second, hyperplastic polyps showed spatial clustering in individuals that was statistically significantly greater than expected from the increased hyperplastic polyp concentration in the rectum and sigmoid. Third, hyperplastic polyps showed spatial clustering with neoplastic polyps; this clustering was similar in magnitude to clustering for exclusively hyperplastic or neoplastic polyps. In contrast, lipomas were not spatially clustered with hyperplastic and neoplastic polyps. The magnitude of clustering between hyperplasia and neoplasia showed a closer association between these histologic types than previously appreciated. Because of clustering, regions with prior polyps appear to merit closer surveillance. These findings suggest clinical study, using a randomized controlled clinical trial, of whether a patient who had only rectal and sigmoid adenomas on initial and follow-up colonoscopy should have surveillance with flexible sigmoidoscopy alternating annually with colonoscopy. A patient with a prior cecal adenoma should have surveillance only with a complete colonoscopy or adequate cecal views on barium enema.
Virtually all colonic polyps may be removed endoscopically and with great safety provided the endoscopist is experienced with diagnostic colonoscopy as well as electrosurgical principles and hazards. Many polypoid protrusions will not require total removal or even sampling. Those lesions thought to need formal surgical management will require not only adequate tissue sampling but also accurate localization for the surgeon.
Between January 1, 1984, and June 30, 1987, we performed percutaneous catheter drainage (PCD) of 28 intra-abdominal abscesses in 21 postoperative trauma patients. During this period only three patients had abdominal re-exploration for drainage of abdominal abscess. The PCD patients were predominantly young men who had sustained penetrating abdominal injuries (81% GSW or SW; 19% MVA). Seventeen (81%) patients had multiple abdominal organ injuries with the colon being the most frequently injured (57%). Multiple abscesses were identified in 33% of the patients. All 21 patients had successful treatment of their abscesses by PCD alone. There was one complication (4.8%) from PCD (pneumothorax) and no deaths in this group. Our data suggest that in most cases, PCD can be safe, effective, and definitive treatment for postoperative intra-abdominal abscesses following abdominal trauma. We recommend PCD in all postoperative trauma patients who develop accessible abdominal abscesses before resorting to re-exploration.
The bacterial flora of colonic aspirates taken after oral administration of a polyethylene glycol-electrolyte lavage solution to patients undergoing colonoscopy was analyzed by standard bacteriological methods and DNA hybridization techniques. The data were compared with those for normal feces collected from the same patients the day before treatment. The results indicate that the bacterial composition of feces differs from individual to individual but is not altered by the oral intake of a polyethylene glycol-electrolyte lavage solution. This pilot study demonstrates that routine colonoscopy aspirates taken after standard colonoscopy preparation accurately reflect the microflora of feces and therefore may be used in large-scale epidemiological studies.
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