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1.
Intern Med ; 55(2): 131-4, 2016.
Article in English | MEDLINE | ID: mdl-26781011

ABSTRACT

Mesenteric panniculitis (MP) is a benign fibroinflammatory process characterized by the presence of fat necrosis, chronic inflammation and fibrosis in the mesentery. Although various causal factors, such as malignancy, chronic inflammatory conditions and autoimmune processes, have been identified, the precise etiology remains unknown. We herein report a rare case of MP accompanying Sjögren's syndrome in which a mass lesion and intestinal stenosis were observed simultaneously. This condition led to ileus, which was effectively treated using prednisolone.


Subject(s)
Ileus/etiology , Intestinal Diseases/etiology , Panniculitis, Peritoneal/complications , Panniculitis, Peritoneal/epidemiology , Sjogren's Syndrome/complications , Sjogren's Syndrome/epidemiology , Aged , Female , Humans , Ileus/drug therapy , Mesentery/pathology , Prednisolone/therapeutic use
2.
J Gastroenterol Hepatol ; 25 Suppl 1: S149-54, 2010 May.
Article in English | MEDLINE | ID: mdl-20586858

ABSTRACT

BACKGROUND AND AIMS: Various etiologies and diseases may be related to erosive and/or small ulcerative lesions without gross appearance in the colon during colonoscopy. However, few investigators report on differential diagnosis of colonic inflammatory diseases. Thus, we investigated the clinical significance of these lesions and the value of colonoscopy in the differential diagnosis of colitis. METHODS: In 110 patients with erosive and/or small ulcerative lesions (<5 mm) who were treated in our hospital during the past 9 years, we retrospectively investigated the relationship between endoscopic morphology and clinical diagnosis. The intestinal lesions were endoscopically classified into three groups (A, hyperemic type; B, aphthous type; and C, verrucous type). RESULTS: The lesions were mainly located in the rectum to the sigmoid colon in group A. In group C, the lesions were most frequently located in the transverse colon and deeper areas. Endoscopically, the etiology was unclear in 74.5% of group A and 73.8% of group B, however, in group C, most of them (81.0%) were associated with specific diseases. With respect to inflammatory bowel diseases, 71.4% of the patients with Crohn's disease and all patients with ulcerative colitis were assigned to group A or B. CONCLUSION: Erosive and/or small ulcerative lesions belonging to group A or B were mainly non-specific. However, careful follow up was required in groups A and B, which included the possibility of inflammatory bowel diseases, when the symptoms or lesions were not improved.


Subject(s)
Colitis, Ulcerative/diagnosis , Colitis/diagnosis , Colon/pathology , Colonoscopy , Crohn Disease/diagnosis , Adolescent , Adult , Aged , Child , Colitis/pathology , Colitis, Ulcerative/pathology , Colon, Sigmoid/pathology , Crohn Disease/pathology , Diagnosis, Differential , Female , Humans , Japan , Male , Middle Aged , Predictive Value of Tests , Rectum/pathology , Retrospective Studies , Video Recording , Young Adult
3.
J Gastroenterol Hepatol ; 25(1): 70-4, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19793169

ABSTRACT

BACKGROUND AND AIM: Capsule endoscopy (CE) is widely used for diagnosing small intestinal diseases. In some cases, however, observation of target sites is very poor during CE because of residues etc. Herein we report the usefulness of a preparation comprised of polyethylene glycol solution (PEG) for CE. METHODS: This was a prospective, randomized, and single-blind study. Forty subjects, fasted for 12 h before CE, were randomized into two groups: 20 subjects in Group A were fasted only, whereas 20 in Group B received 1 liter (L) PEG with 200 mg dimethylpolysiloxane 3 h before CE. For evaluation, the observation period of the small intestine was divided into first and second halves. Subsequently, four investigators, blinded as to which group received the preparation, assessed the condition of the intestine using four rating scales in terms of 'residue' and 'intraluminal gas bubbles'. The effects of the preparation were statistically compared. RESULTS: CE images were better in Group B than in Group A with respect to 'intraluminal gas bubbles' (P = 0.0038) in the first half of the observation period, as well as residue (P = 0.0087) and intraluminal gas bubbles (P = 0.0011) in the second half. CONCLUSION: Bowel preparation using 1 L PEG with dimethylpolysiloxane 3 h before CE significantly reduced residue and intraluminal gas bubbles, and was considered to be a useful method for CE.


Subject(s)
Antifoaming Agents/therapeutic use , Capsule Endoscopy , Dimethylpolysiloxanes/therapeutic use , Gastrointestinal Agents/therapeutic use , Intestinal Diseases/pathology , Intestine, Small/pathology , Polyethylene Glycols/therapeutic use , Adolescent , Adult , Aged , Aged, 80 and over , Fasting , Female , Gases , Humans , Male , Middle Aged , Pharmaceutical Solutions , Predictive Value of Tests , Prospective Studies , Single-Blind Method , Time Factors , Young Adult
4.
Hepatogastroenterology ; 55(82-83): 422-5, 2008.
Article in English | MEDLINE | ID: mdl-18613379

ABSTRACT

BACKGROUND/AIMS: The aim of this research is to investigate the international and intra-observer differences in the macroscopic classification of early colorectal cancer between Japan and China. METHODOLOGY: Color pictures of 9 cases of early colorectal cancer were distributed to 6 Japanese and 5 Chinese endoscopists. After reviewing the pictures, the doctors made their classificatory diagnoses independently and indicated their findings on which the diagnoses were based. RESULTS: There was some consistency in the classification of distinctly elevated lesions among all the Japanese and Chinese endoscopists. However, some elevated lesions classified as type II in Japan might be diagnosed as type I by Chinese endoscopists. For superficial lesions consisting of elevation plus central depression, IIa+IIc or IIc+IIa, were classified according to the ratio of elevation and depression. Although international difference is not significant, inter-observer differences still exist in classifying these lesions. In addition, the differences in laterally spreading tumor were mainly due to terminology. CONCLUSIONS: Japanese and Chinese doctors share a lot of similarities in the classification of flat elevated lesions; however, both international and inter-observer differences still exist in the macroscopic classification for early CRC.


Subject(s)
Colonoscopy/statistics & numerical data , Colorectal Neoplasms/classification , Colorectal Neoplasms/pathology , Humans , Observer Variation
5.
J Gastroenterol ; 43(7): 576-80, 2008.
Article in English | MEDLINE | ID: mdl-18648746

ABSTRACT

A case of primary NK/T-cell lymphoma of the rectum accompanied with ulcerative colitis (UC) in a 73-year-old man is reported. He had a 6-year history of repeated admission to our hospital for UC. Total colonoscopy performed 4 months after resolution of refractory UC complicated by cytomegalovirus colitis showed a markedly submucosal tumor in the rectum, which was histologically diagnosed as malignant lymphoma. The findings of computed tomography of the chest and abdomen, gallium scintigraphy, abdominal ultrasonography, and upper gastrointestinal endoscopy showed no abnormal lesions. Therefore, based on a diagnosis of localized rectal lymphoma with UC, proctocolectomy was performed. The resected specimen showed three submucosal tumors in the rectum with local nodal involvement. Histologically, the tumors were characterized by diffusely infiltrating sheets of large atypical lymphoid cells, which were negative for CD4, CD8, and CD20 but were positive for CD56, CD3, and granzyme B. The presence of Epstein-Barr virus (EBV) infection in neoplastic cells was shown by in situ hybridization for EBV-encoded early small RNA1 (EBER-1). Based on these findings, the patient was diagnosed with primary CD56+ NK/T-cell lymphoma of the rectum (stage IIE). This is the first case report of primary rectal NK/T-cell lymphoma accompanied with UC.


Subject(s)
CD56 Antigen/analysis , Colitis, Ulcerative/complications , Lymphoma, Extranodal NK-T-Cell/complications , Rectal Neoplasms/complications , Aged , Humans , Immunohistochemistry , Lymphoma, Extranodal NK-T-Cell/immunology , Lymphoma, Extranodal NK-T-Cell/pathology , Male , Rectal Neoplasms/immunology , Rectal Neoplasms/pathology
6.
J Gastroenterol ; 43(1): 45-50, 2008.
Article in English | MEDLINE | ID: mdl-18297435

ABSTRACT

BACKGROUND: Detection and removal of adenomas by colonoscopy is an important means for preventing cancer; however, small adenomas may be missed during colonoscopy. The narrow-band imaging (NBI) system clearly enhances the microvasculature in neoplastic lesions, making it appear as a dark complex. Therefore, the NBI system may improve the detection of colonic neoplasias. However, no randomized, controlled trials have evaluated the efficacy of a pan-colonic NBI system in adenoma detection. We conducted a randomized, controlled trial to determine the efficacy of the pancolonic NBI system in adenoma detection. METHODS: Two hundred forty-three patients were randomized, 121 to conventional colonoscopy and 122 to pan-colonic NBI system. Demographics, indication for colonoscopy, and quality of preparation were similar between groups. RESULTS: Extubation time was not significantly different between the conventional colonoscopy and pan-colonic NBI system. The proportions of patients with at least one adenoma and those with multiple adenomas were not significantly different between groups. However, the pan-colonic NBI system significantly increased the total number of adenomas detected (P < 0.05) and the number of diminutive (<5 mm) adenomas detected (P < 0.05). The pan-colonic NBI system allowed detection of more diminutive adenomas in the distal colon than did conventional colonoscopy (P < 0.01), and more patients in the NBI group had at least one diminutive adenoma than in the control group (P < 0.05). CONCLUSIONS: The pan-colonic NBI system improves the total number of adenomas detected, including significantly more diminutive adenomas, without prolongation of extubation time. These results indicate that routine use of the NBI system for surveillance of diminutive adenomas may be recommended.


Subject(s)
Colonic Polyps/pathology , Colonoscopy/methods , Diagnostic Imaging/instrumentation , Biopsy , Colonoscopes , Diagnosis, Differential , Equipment Design , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Video Recording/instrumentation
7.
Oncol Rep ; 18(6): 1457-62, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17982630

ABSTRACT

Patients with ulcerative colitis (UC) exhibit an increased risk for the development of cancer of the colon and rectum. This association is widely attributed to colonic inflammation. However, the severity of colonic inflammation necessary for the development of dysplasia and/or cancer remains unknown. In this study, we investigated the pattern of cell proliferation in colorectal carcinogenesis in an experimental murine model of UC. Chronic colitis was induced by administration of four cycles of dextran sulfate sodium (DSS) (each cycle: 5% or 2% DSS for 7 days and then distilled water for 14 days). Mice were sacrificed after every cycle and at 120 days following the completion of the fourth cycle. Colonic cell proliferation was immunohistochemically evaluated using the thymidine analogue bromodeoxyuridine and the labeling index (LI) was determined. The incidence of dysplasia and/or cancer was 28%, 6.7%, and 0% in the 5% DSS, 2% DSS, and normal control groups respectively. All gross lesions were present in the middle to distal colon. Disease activity index and total LI after four cycles of DSS were significantly higher in the 5% DSS group compared to the 2% DSS group. In the 5% DSS group, the LI was significantly higher in the middle colon than in the proximal colon. Simple repeated administration of the non-genotoxic colon carcinogen DSS induced dysplasia and/or cancer. In addition, we have demonstrated the presence of regional differences in proliferation pattern between the middle and the proximal colon during carcinogenesis in experimental murine UC. These findings may provide insight into the development of colorectal cancer in humans with long-standing UC.


Subject(s)
Colitis, Ulcerative/complications , Colon/pathology , Colorectal Neoplasms/pathology , Animals , Carcinogens , Colorectal Neoplasms/etiology , Dextran Sulfate , Disease Models, Animal , Female , Mice , Mice, Inbred BALB C
8.
J Gastroenterol Hepatol ; 22(9): 1474-81, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17716351

ABSTRACT

BACKGROUND: Patients with ulcerative colitis (UC) exhibit an increased risk for the development of cancer of the colon and rectum. Cyclooxygenase (COX)-2 inhibitors are known to suppress sporadic colorectal cancer, but it is unknown whether selective COX-2 inhibitors exhibit a preventive effect in UC-associated neoplasia. This study investigated the preventive effect of nimesulide, a selective COX-2 inhibitor, on colorectal carcinogenesis in an experimental model of murine UC. METHODS: Chronic colitis was induced in mice by administration of four cycles of dextran sulfate sodium (DSS) (each cycle: 5% DSS for 7 days and then distilled water for 14 days). The mice were killed 120 days after the completion of the fourth cycle. The mice were divided into the following five groups: group A served as a disease control; group B received a diet mixed with 400 p.p.m. of nimesulide during the whole period; group C received nimesulide during the four cycles of DSS administration (active phase); group D received nimesulide for 120 days from the end of the fourth cycle (remission phase); group E received no agents including DSS and served as a normal control. RESULTS: The incidence of dysplasia and/or cancer was 28%, 15%, 11.8%, 6.7% and 0% in groups A-E, respectively. In group D, nimesulide significantly suppressed the occurrence of dysplasia and/or cancer (P < 0.05). Strong COX-2 expression was detected by immunohistochemistry in cancer and dysplastic lesions while diffusely weak COX-2 expression was also found in the residual colon (i.e. lesion-free colon). The mucosal concentration of prostaglandin E(2) was significantly lower in groups B and D than in group A. CONCLUSIONS: The administration of the selective COX-2 inhibitor nimesulide (especially during the remission phase) exerts a suppressive effect on the development of dysplasia and/or cancer in a murine model of DSS-induced colitis. These findings may have relevance to long-standing UC in humans.


Subject(s)
Colitis, Ulcerative/drug therapy , Colorectal Neoplasms/etiology , Colorectal Neoplasms/prevention & control , Cyclooxygenase Inhibitors/therapeutic use , Sulfonamides/therapeutic use , Animals , Colitis, Ulcerative/complications , Colorectal Neoplasms/pathology , Dinoprostone/metabolism , Disease Models, Animal , Female , Mice , Mice, Inbred BALB C
9.
Hepatogastroenterology ; 54(76): 990-4, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17629023

ABSTRACT

BACKGROUND/AIMS: Helicobacter pylori (HP) infection is reported to be involved in gastric carcinogenesis. However, only a small percentage of HP-infected patients actually develop gastric cancer. In the present study, we assessed HLA antigen polymorphism and investigated its relationship with the development of gastric epithelial tumors in patients who had HP infection. METHODOLOGY: Among patients with serologically proven HP infection, 80 cases who underwent endoscopic mucosectomy for gastric epithelial tumors (24 adenomas and 56 carcinomas) were recruited in the study (the tumor group), and 20 cases without tumors were also included as controls (the nontumor group). HLA status (HLA-A, HLA-B, HLA-DRB1 and HLA-DQB1) was determined by HLA-DNA typing. RESULTS: HLA-B*05401, HLA-DQB1*0601 and HLA-DRB1*1502 genes showed a significantly higher frequency in the control group than in the tumor group (0.225 vs. 0.088, P=0.015; 0.3 vs. 0.163, P = 0.047; 0.175 vs. 0.069, P = 0.036, respectively). CONCLUSIONS: It suggests that HLA-B*5401, HLA-DQB1*0601 and HLA-DRB1*1502 may contribute to the inhibition of gastric carcinogenesis. Thus, HP-infected patients without these genotypes should undergo HP eradication therapy and close follow-up.


Subject(s)
Genetic Predisposition to Disease/genetics , HLA Antigens/genetics , Helicobacter Infections/complications , Helicobacter pylori , Stomach Neoplasms/immunology , Adult , Aged , Aged, 80 and over , Female , Genotype , Humans , Male , Middle Aged , Stomach Neoplasms/genetics , Stomach Neoplasms/microbiology
10.
World J Gastroenterol ; 13(14): 2048-52, 2007 Apr 14.
Article in English | MEDLINE | ID: mdl-17465446

ABSTRACT

AIM: To investigate the histopathological and genetic differences between polypoid growth (PG) and non-polypoid growth (NPG) submucosal invasive colorectal carcinoma (CRC). METHODS: A total of 96 cases of submucosal CRC were divided into two groups according to their growth type; 60 cases of PG and 36 cases of NPG. The size, histological degree of dysplasia, depth of submucosal invasion and lymph node metastasis were compared between the two groups. Furthermore, expression of p53 was detected by immunohistochemical staining, and K-ras gene mutation was examined by polymerase chain reaction based single-strand conformation polymorphism (SSCP). RESULTS: The average size of the lesions in the NPG group was significantly smaller than those in the PG group (7.5 mm vs 13.8 mm, P<0.001). The histological degree of dysplasia tended to be more severe in NPG group, while the incidence of submucosal massive invasion and the lymph node metastasis were both significantly higher in the NPG type than in the PG group (64.3% vs 43.3%, P=0.004; 43% vs 7%, P=0.008, respectively). In addition, K-ras gene mutations were detected in 67% of lesions in the PG group, but none in the NPG group, while no difference in p53 immunohistochemical expression was found between the two groups. CONCLUSION: Compared with PG submucosal CRC, NPG type demonstrates more frequent submucosal massive invasion, more lymph node metastasis and a higher degree dysplasia. Genetically, NPG type shows much less frequent K-ras mutation.


Subject(s)
Carcinoma/genetics , Carcinoma/pathology , Cell Proliferation , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Adenocarcinoma/diagnosis , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Adenoma/diagnosis , Adenoma/genetics , Adenoma/pathology , Carcinoma/diagnosis , Colorectal Neoplasms/diagnosis , Diagnosis, Differential , Disease Progression , Gene Expression Regulation, Neoplastic , Humans , Lymphatic Metastasis/genetics , Lymphatic Metastasis/pathology , Mutation/genetics , Polymorphism, Single-Stranded Conformational , Proto-Oncogene Proteins p21(ras)/genetics , Proto-Oncogene Proteins p21(ras)/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism
11.
World J Gastroenterol ; 13(10): 1569-74, 2007 Mar 14.
Article in English | MEDLINE | ID: mdl-17461450

ABSTRACT

AIM: To evaluate prospectively usefulness of fecal lactoferrin (Lf) and fecal hemoglobin (Hb) in the diagnosis of colorectal diseases. METHODS: Fecal Lf and Hb were measured using ELISA in 872 patients before they underwent colorectal endoscopy. RESULTS: Lf was positive in 18 (50%) of 36 patients with colorectal cancer, 25 (15.9%) of 157 with colorectal polyps, 29 (46.8%) of 62 with ulcerative colitis, and 25 (62.5%) of 40 (62.5%) with Crohn's disease. The Hb-positive rates were 50%, 12.1%, 41.9% and 32.5%, respectively. Of the 318 patients free of abnormalities by colorectal endoscopy, Lf was positive in 29 (9.1%) and Hb was positive in 15 (4.7%). Among patients with Crohn's disease, the Lf-positive rate was significantly higher than the Hb-positive rate. If either high Lf or Hb levels were considered positive, the positive rates rose to 61.1%, 51.6%, and 67.5% in the colorectal cancer group, ulcerative colitis group, and Crohn's disease group, respectively. If both high Lf and Hb levels were rated positive, the positive predictive values (PPV) were 21% for colorectal cancer, 33% for ulcerative colitis, and 17% for Crohn's disease, and PPV of high Hb level alone was 18%, 25% and 13%, respectively. CONCLUSION: Fecal Lf and Hb were found useful in the detection of colorectal diseases, and the combination of the two measurements appears to increase the sensitivity and efficacy of diagnosis.


Subject(s)
Colonic Diseases/diagnosis , Colorectal Neoplasms/diagnosis , Hemoglobins/analysis , Lactoferrin/analysis , Rectal Diseases/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/metabolism , Child , Colonic Diseases/metabolism , Colorectal Neoplasms/metabolism , Endoscopy, Gastrointestinal , Feces/chemistry , Hemoglobins/metabolism , Humans , Lactoferrin/metabolism , Middle Aged , Predictive Value of Tests , Prospective Studies , Rectal Diseases/metabolism , Sensitivity and Specificity
12.
World J Gastroenterol ; 13(11): 1666-71, 2007 Mar 21.
Article in English | MEDLINE | ID: mdl-17461468

ABSTRACT

AIM: To evaluate the effect of pyrrolidine dithio-carbamate (PDTC; an NF-kappaB inhibitor) administered at low (50 mg/kg) and high (100 mg/kg) doses in suppressing colitis in mice with dextran sodium sulfate (DSS)-induced colitis. METHODS: Mice were divided into a DSS-untreated group (normal group), DSS-treated control group, DSS+PDTC-treated group I (low-dose group), and DSS+PDTC-treated group II (high-dose group). In each group, the disease activity index score (DAI score), intestinal length, histological score, and the levels of activated NF-kappaB and inflammatory cytokines (IL-1beta and TNF-alpha) in tissue were measured. RESULTS: The DSS+PDTC-treated group II exhibited suppression of shortening of intestinal length and reduction of DAI score. Activated NF-kappaB level and IL-1beta and TNF-alpha levels were significantly lower in DSS+PDTC-treated group II. CONCLUSION: These findings suggest that PDTC is useful for the treatment of ulcerative colitis.


Subject(s)
Antioxidants/pharmacology , Colitis/drug therapy , Inflammation/drug therapy , Pyrrolidines/pharmacology , Thiocarbamates/pharmacology , Animals , Antioxidants/administration & dosage , Colitis/chemically induced , Colitis/pathology , Colon/metabolism , Colon/pathology , Dextran Sulfate , Disease Models, Animal , Female , Indicators and Reagents , Inflammation/chemically induced , Inflammation/pathology , Injections, Intraperitoneal , Interleukin-1beta/metabolism , Mice , Mice, Inbred BALB C , NF-kappa B/metabolism , Pyrrolidines/administration & dosage , Severity of Illness Index , Thiocarbamates/administration & dosage , Tumor Necrosis Factor-alpha/metabolism
13.
World J Gastroenterol ; 11(33): 5241-4, 2005 Sep 07.
Article in English | MEDLINE | ID: mdl-16127763

ABSTRACT

Various hepato-biliary complications are an increased incidence in patients with inflammatory bowel disease, and portal bacteremia is well documented in patients with ulcerative colitis (UC). However, few reports mention UC in association with liver abscesses. Recently, there are several reports describing cytomegalovirus (CMV) infection in association with disease exacerbation and steroid refractoriness in patients with UC. Here we present a case of refractory UC accompanied with multiple liver abscesses and CMV colitis. The patient, a 72-year-old male, with a five-year history of repeated admissions to our hospital for UC, presented with an exacerbation of his UC. Sigmoidoscopy performed on admission suggested that his UC was exacerbated, then he was given prednisolone and mesalazine orally, and betamethasone enemas. However, he had exacerbated symptoms. Repeat sigmoidoscopy revealed multiple longitudinal ulcers and pseudopolyps in the rectosigmoid colon. Although immunohistochemical staining of biopsy specimens and the serum testing for antigenemia were negative on admission and after the repeat sigmoidoscopy, they became histologically positive for CMV. Nonetheless, the patient developed spiking fevers, soon after ganciclovir was administered. Laboratory studies revealed an increased white cell count with left shift, and Enterococcus fecalis grew in blood cultures. An abdominal computed tomography (CT) scan was obtained and the diagnosis of liver abscesses associated with UC was made, based on CT results. The hepatic abscesses were successfully treated with intravenous meropenem for 6 wk, without further percutaneous drainage. To our knowledge, this is the first reported case of multiple liver abscesses that develop during UC exacerbation complicated by CMV colitis.


Subject(s)
Colitis, Ulcerative/complications , Colitis/complications , Colitis/virology , Cytomegalovirus Infections , Liver Abscess/complications , Aged , Colitis, Ulcerative/physiopathology , Humans , Male
14.
Clin Chim Acta ; 318(1-2): 107-12, 2002 Apr.
Article in English | MEDLINE | ID: mdl-11880119

ABSTRACT

BACKGROUND: We examined a technique for detecting point mutations of K-ras codon 12 in stool samples using one-step polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) analysis, in order to determine whether it could be used to screen for colorectal cancer. METHODS: DNA was extracted from 200-mg stool specimens of 5 healthy controls and 31 colorectal cancer patients. A 107-base-pair fragment of exon 1 of K-ras was amplified by PCR using mismatched primers. PCR products were digested with Bst NI and analyzed by gel electrophoresis followed by silver staining. Specificity of one-step PCR/RFLP was examined by using synthetic oligonucleotides. The detection limit of K-ras codon 12 mutations was determined by using SW480 and HT29 cells. RESULTS: The K-ras gene was successfully amplified from all healthy controls and colorectal cancer patients studied. Mutations of K-ras codon 12 were not detected in any of the healthy controls, but were identified in 13 (41.9%) of the 31 patients with colorectal cancer. Mutations were detectable in all six synthetic mutant DNAs, while none were detected among the wild type. The detection limit of this method was > or = 0.1%. CONCLUSIONS: PCR/RFLP analysis could be used in mass screening for colorectal cancer, because it is highly specific, has a low detection limit, and is simpler than conventional methods for detecting genetic abnormalities.


Subject(s)
Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Feces/chemistry , Genes, ras/genetics , Point Mutation/genetics , Adult , Aged , Aged, 80 and over , DNA/genetics , DNA/isolation & purification , DNA Primers , Female , Humans , Male , Middle Aged , Polymorphism, Restriction Fragment Length , Reverse Transcriptase Polymerase Chain Reaction , Tumor Cells, Cultured
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