Typing of clinical isolates of Mycobacterium leprae and their distribution in Korea

Although there is no genetic diversity in isolates of Mycobacterium leprae, the variance of tandem repeats in the rpoT gene was recently demonstrated. We have typed clinical isolates of M. leprae in Korea using difference of the tandem repeats in the rpoT gene. Among 69 patients, 65 Korean isolates (94.2%) demonstrated four copies of the 6 bp tandem repeat (GACATC) in the rpoT gene, and incidences of three copies were found in only two Koreans and two foreigners (2.9%, respectively).

Genotypic prevalence of the fimbrial adhesins (F4, F5, F6, F41 and F18) and toxins (LT, STa, STb and STx2e) in Escherichia coli isolated from postweaning pigs with diarrhoea or oedema disease in Korea

A PCR was used to determine the genotypic prevalence of five fimbrial adhesins (F4, F5, F6, F41 and F18), two heat-stable enterotoxins (STa and STb), the heat-labile enterotoxin (LT), and the shiga toxin 2e (Stx2e) in 230 isolates of Escherichia coli from postweaning pigs with diarrhoea or oedema disease. Ninety-four (40.9 per cent) of the isolates carried genes for at least one of the fimbrial adhesins or toxins. Genes for the F18 fimbrial adhesin were detected in 18.3 per cent, and genes for F4, F6, F5 and F41 were detected in 10.0 per cent, 4.3 per cent, 1.7 per cent and 0.8 per cent of the isolates, respectively. Genes for STa, STb and LT were detected in 25.7 per cent, 15.2 per cent and 8.7 per cent of the isolates, respectively. Genes for Stx2e were detected in 36 (15.6 per cent) of the isolates, and among them 24 also contained the gene for F18ab and four also contained the gene for F18ac.

Molecular cloning and characterization of mouse cardiac triadin isoforms

Triadin is a ryanodine receptor and calsequestrin binding protein located in junctional sarcoplasmic reticulum of striated muscles. In the present study, mouse cardiac triadin cDNAs have been identified by cDNA library screening and RT-PCR. The deduced aa sequences show that the three isoforms consist of 277, 293 and 305 aa giving rise to the molecular weights of approximately 31,414, 33,066, and 34,328, respectively. The isoforms have identical 262 aa N-terminal sequences, whereas they have distinct C-terminal sequences. Northern blot analysis using a cDNA probe representing the N-terminal common region of triadin revealed that the mouse triadins were present both in heart and skeletal muscles. The estimated sizes of the transcripts were approximately 1.3, 4.3 and 5 kb in heart and 5, 5.5 and 7 kb in skeletal muscle. Endo H treatment and Western blot analysis of isolated mouse cardiac sarcoplasmic reticulum and in vitro translation products indicate that there are three distinct mouse cardiac triadin isoforms having molecular weights of 35, 35.5 and 40 kDa. We termed those three isoforms as mouse cardiac triadin 1, mouse cardiac triadin 2 and mouse cardiac triadin 3.

Prolonged organ retention and safety of plasmid DNA administered in polyethylenimine complexes

Polyethylenimine (PEI) has been studied as an efficient nonviral gene transfer vector. Here, we report the biodistribution fates and safety of plasmid DNA intravenously administered in PEI complexes. Using pCMVbeta as a model gene, the biodistribution of plasmid DNA was measured by quantitative polymerase chain reaction. A deletion mutant of pCMVbeta was used as an internal standard. After intravenous administration of PEI/DNA complexes, the serum levels of DNA rapidly declined for up to 15 min. However, after this point, the serum levels of DNA diminished slowly. At 15 min after dose, PEI/DNA complexes showed 33-fold higher distribution of DNA in the lung than did naked DNA. At 24 h, all the organs tested showed much higher levels of plasmid DNA in PEI/DNA complexes, with distribution in the liver and lung being three orders of magnitude higher than naked DNA. The mRNA expression of DNA was observed in various organs of PEI/DNA-treated mice at 12 days after dose. Once a week dosing of PEI/DNA complexes over 3 consecutive weeks did not alter the histology of the organs. However, twice a week dosing over 3 weeks induced a sign of inflammation in the liver. These results indicate that PEI enhances the delivery and retention of plasmid DNA in the organs, especially the liver, but that safe delivery requires proper dosing intervals.

Influence of the number of lymph nodes examined on staging of gastric cancer

BACKGROUND

Nodal staging for gastric cancer according to the 1997 Union Internacional Contra la Cancrum tumour node metastasis classification is based on the number of metastatic lymph nodes. The aim of this study was to evaluate whether the number of lymph nodes examined affected staging of gastric cancer.

METHODS

A retrospective study was performed in 4789 consecutive patients with gastric cancer, who had undergone curative resection (R0) from 1986 to 1995. Patients were classified according to the number of nodes examined. The number of metastatic lymph nodes and stage-stratified survival were compared.

RESULTS

There were significant differences in the number of metastatic lymph nodes and survival in stage IIIA between patients with 15 or more lymph nodes and those with fewer than 15 nodes. In analysis restricted to patients with 15 or more nodes, stage-stratified survival did not vary significantly with lymph node yields for any stage except IIIB, in which there was a significant difference between the subgroup with fewer than 20 examined lymph nodes and patients with 35 or more nodes.

CONCLUSION

The number of lymph nodes examined did not significantly affect node staging of gastric cancer as long as at least 15 nodes were examined. For stage IIIB, more than 15 lymph nodes may be required for optimal staging.

Results of immunochemo-surgery for gastric carcinoma

BACKGROUND/AIMS

Although the therapeutic results of gastric cancer have markedly improved, it still remains the most common cancer death in Korea.

METHODOLOGY

The clinicopathologic characteristics were analyzed for 11,491 consecutive patients who underwent operation for gastric cancer at the Department of Surgery, Seoul National University Hospital from 1971 to 1997. We also evaluated the survival and prognostic factors for 9,262 consecutive patients from 1981 to 1996. The prognostic significance of treatment modality [surgery alone, surgery + chemotherapy, surgery + immunotherapy + chemotherapy (immunochemo-surgery)] were evaluated in stage III gastric cancer.

RESULTS

The 5-year survival rate of overall patients was 55.8%, and that of patients who received curative resection was 64.8%. The 5-year survival rates according to TNM stage were 92.9% for Ia, 84.2% for Ib, 69.3% for II, 45.8% for IIIa, 29.6% for IIIb and 9.2% for IV. Depending on the extent of resection, the 5-year survival rates were 68.7% for STG, 45.4% for TG, 19.6% for combined resection and there was no 5-year survivor in the nonresection group. Regarding adjuvant treatment modality, significant survival difference was observed in stage III patients. The 5-year survival rates were 44.8% for the immunochemo-surgery group, 36.8% for the surgery + chemotherapy group and 27.2% for the surgery alone group.

CONCLUSIONS

Curative resection, depth of invasion and lymph node metastasis were the most significant prognostic factors in gastric cancer. Consequently, early detection and curative resection with radical lymph node dissection, followed by immunochemotherapy especially in patients with stage III gastric cancer should be recommended as a standard treatment principle for patients with gastric cancer.

Nasal absorption and biodistribution of plasmid DNA: an alternative route of DNA vaccine delivery

Nasal administration is emerging as a new route of DNA vaccine delivery. We aimed to study the extent of absorption and biodistribution of intranasally administered plasmid DNA. After intranasal administration, the level of plasmid DNA in the serum peaked at 1.5 h. The ratio of the area under the concentration (AUC) after intranasal administration of DNA over the AUC after intravenous administration was 0.14. At 15 min post inoculation, the highest organ distribution was observed in the liver and the cervical lymph nodes showed the highest level among the lymph nodes. At 24 h a higher localization of plasmids to the brain than to the lung and spleen was notable. A significant level of mRNA expression was observed in the lymph nodes. These results suggest that plasmid DNA can be substantially absorbed and distributed to the lymph nodes after intranasal administration, partly explaining the systemic immunogenicity of intranasally administered plasmid DNA vaccines.

Ellagic acid rhamnosides from the stem bark of Eucalyptus globulus

Four ellagic acid rhamnosides were isolated from the stem bark of Eucalyptus globulus. Their structures have been established on the basis of the analysis of their 1H NMR, 13C NMR, HMBC, IR and MS spectral data. The HMBC data of these compounds were most useful for their structure determinations, with these bring determined to be 3-O-methylellagic acid 3'-O-alpha-rhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-3''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-2''-O-acetylrhamnopyranoside, 3-O-methylellagic acid 3'-O-alpha-4''-O-acetylrhamnopyranoside, respectively. Their antioxidant activities were evaluated by measuring the inhibition of lipid peroxidation using rat liver microsomes, with IC50 values of 10.0-14.0 microg/ml.

A Clinicopathological Analysis of Recurrent Gastric Cancer

PURPOSE

This study was designed to investigate the correlation between the clinicopathologic characteristics and the recurrence pattern of gastric cancer and to define survival difference according to treatment modality after diagnosis of recurrence.

MATERIALS AND METHODS

We retrospectively reviewed the medical records of 4184 patients who had undergone radical surgery for primary gastric cancer from 1986 through 1996. Clinicopathologic factors were analyzed for the relationship of each factor with the pattern of recurrence. And the survival after diagnosis of recurrence was compared among the treatment modalities.

RESULTS

Recurrence pattern was confirmed in 1141 patients. Loco-regional recurrence occurred in 291 patients (20.1%), peritoneal recurrence in 383 (26.5%), distant recurrence in 290 (20.1%), and mixed recurrence in 177 (12.3%), respectively. Early recurrence (less than 2 years) occurred in 767 (69.3%), intermediate recurrence (2~5 years) in 286 (25.8%), and late recurrence (more than 5 years) in 54 (4.9%). In multivariate analysis, T stage, N stage, size of tumor and perineural invasion were independent prognostic factors for recurrence. Median survival from diagnosis of recurrence was 24.2 months in the curative operation group, 7.7 months in the chemotherapy group, 7.1 months in the non-curative operation group and 3.3 months in the conservative treatment group, respectively (p=0.000).

CONCLUSION

The clinicopathological analysis of recurrent gastric cancer showed recurrent patterns and prognostic factors. Curative resection is suggested to have survival benefit in recurrent gastric cancer patients, although it was possible in patients with limited extent of disease.

Nitric oxide mediates platelet activating factor-induced microvascular leakage in rat airways

Platelet activating factor (PAF), a highly potent chemical mediator in inflammation and allergic reactions, induces microvascular leakage in several tissues. In rat airways, PAF-induced microvascular leakage is probably mediated by an endothelial cell receptor in the microvessels. Nitric oxide (NO), first identified as endothelium-derived relaxing factor, has been suggested to be a mediator of airway microvascular leakage. However, the role of NO in PAF-induced microvascular leakage in the airways has not yet been established. The aim of this study was to investigate the role of NO in PAF-induced microvascular leakage in rat nasal mucosa and trachea. We injected PAF (1 microg/kg) intravenously, and the amount of PAF-induced microvascular leakage was measured with extravasation of Evans blue dye (30 mg/kg, injected intravenously 5 minutes before the injection of PAF) by means of spectrophotometry and fluorescence microscopy. Five Sprague-Dawley rats were pretreated with NG-nitro-L-arginine methyl ester (L-NAME; 10 mg/kg, intravenously injected 1 hour before the injection of PAF) to inhibit NO synthase, and control rats (n = 4) were pretreated with normal saline solution. The average amount of extravasated Evans blue dye was significantly lower in the L-NAME-pretreated rats than in the control rats (t-test, p < .01). Tissue sections of the L-NAME-pretreated rats clearly showed a decreased extravasation of Evans blue dye on fluorescence microscopy. In conclusion, pretreatment with L-NAME clearly inhibited PAF-induced microvascular leakage in the nasal mucosa and trachea of rats. This finding implies that PAF may activate the constitutive endothelial NO synthase in the microvessels, and that activated endogenous NO may mediate PAF-induced microvascular leakage in rat airways.

Methyl mercury bioaccumulation in long-finned eels, Anguilla dieffenbachii, from three rivers in Otago, New Zealand

This research focuses on mercury (Hg) bioaccumulation in New Zealand long-tinned eels (Anguilla dieffenbachii) from the aquatic environment. Total Hg (HgT) and methyl mercury (MeHg) concentrations were determined in muscle tissue from eels living in three South Island rivers dominated respectively by urban, native bush and agricultural land-uses. Most of the Hg in eels was MeHg (> 84%) and the MeHg concentrations increased linearly with both length and eel age for a given river habitat. The annual growth rates for eels from the urban and agricultural streams were greater than for eels from the native bush stream. The average MeHg accumulation rate was significantly higher for the eels in the agricultural stream compared with either the urban or native bush catchments. These results are probably due to a combination of factors and further investigations in the lower food web are necessary to elucidate the exact mechanisms of MeHg bioaccumulation in these creatures.

Multiplex in-cell reverse transcription-polymerase chain reaction for the simultaneous detection of p210 and p190 BCR-ABL mRNAs in chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia cell lines

We designed a novel multiplex in-cell reverse transcription-polymerase chain reaction method for the simultaneous detection and differentiation of p190 and p210 BCR-ABL mRNAs within single cells from the human chronic myeloid leukemia and Philadelphia positive acute lymphoblastic leukemia. Human K562 chronic myeloid leukemia and SUP B-15 Ph+ acute lymphoblastic leukemia cell lines were used as positive controls for p210 and p190 BCR-ABL mRNAs, respectively. HL60 cell line was used as a negative control. After the leukemia cells were fixed and permeabilized, without extracting nucleic acids, the mRNAs were reverse transcribed to cDNAs, and the cDNAs were amplified by multiplex polymerase chain reaction with fluorescent primers specific for p190 and p210 BCR-ABL mRNAs. After transfer onto glass slides by cytospin, the amplified cells were detected by fluorescence microscopy. Fluorescence microscopy after propidium iodide or 4',6-diamidino-2-phenylindone counterstaining showed that the positive K562 cells exhibited a yellow-green fluorescent cytoplasm around a red nucleus, and that the positive SUP B-15 cells exhibited an orange cytoplasm around a blue nucleus. Only the red or blue nucleus was visible in respective negative HL60 cells. The specificity of amplification was confirmed by the absence of a signal when control experiments were performed either with RNase digestion of mRNA or without reverse transcriptase/Taq polymerase. We conclude that the multiplex in-cell reverse transcription-polymerase chain reaction method is capable of simultaneously detecting and differentiating the p210 and p190 BCR-ABL mRNAs of chronic myeloid leukemia and Philadelphia-positive acute lymphoblastic leukemia cells, and that it may be useful in quantitatively monitoring the minimal residual disease during therapy.

Microsatellite instability and Epstein-Barr virus infection in gastric remnant cancers

Clinicopathological analysis, microsatellite analysis, detection of Epstein-Barr virus (EBV), and immunohistochemistry on p53 protein were performed in 26 cases of gastric remnant cancer (GRC). They were divided into two groups; Group A (n = 14) who had undergone a primary gastrectomy for benign gastric disease, and Group B (n = 12) who had undergone the same operation for gastric cancer. EBV infection was present in 29% of Group A, 8% of Group B and 6% of the conventional gastric carcinoma (CGC) (Group A vs CGC, P = 0.01). Microsatellite instability (MSI) was found in 7% of Group A, 25% of Group B, and 9% of the CGC (Group B vs CGC; P = 0.08). p53 Overexpression was observed in 46% of the GRC and 33% of the CGC. p53 Overexpression was observed in 90% of the intestinal type of GRC, but in only 20% of the diffuse type of GRC (P = 0.002). The cancer stage was a significant factor in the univariate analysis of survival (P = 0.04). In conclusion, GRC is different from CGC in terms of MSI or EBV association. The pathogenetic differences between the two groups require further investigation. EBV infection may have been involved in the carcinogenesis of Group A. MSI may be an important factor in the carcinogenesis of metachronous multiple gastric cancer (Group B).

Result of 11,946 gastric cancer treatment with immunochemosurgery

Although the therapeutic results of gastric cancer have markedly improved, it still remains the most common of cancer deaths in Korea. Annually more than 700, and all together 11,946, gastric cancer patients were surgically treated from 1970 to 1998 at Seoul National University Hospital. Stage III gastric cancer is already a systemic disease, Radical surgery alone cannot cure the patient, and about 35% recurred within 2-3 years. To improve the prognosis of advanced gastric cancer, systemic treatment such as immunotherapy and chemotherapy is required in the early postoperative period to kill the micrometastatic or remaining cancer cells after curative resection. We evaluated the survival rate and prognostic factors for 9,262 consecutive patients from 1981 to 1996. The clinicopathologic variables used for evaluating prognostic values were classified into patient, -tumor- and treatment-related factors. The prognostic significance of treatment modality was evaluated in stage III gastric cancer. The five-year survival rates were 55.9% for overall patients and 64.8% for patients who received curative resection. Radical lymph node dissection was found to produce survival gains in patients with stage II and IIIa. For postoperative adjuvant therapy, immunochemotherapy was most effective in patients with stage III. In multivariate analysis, curability of operation, depth of invasion, and ratio of involved-to-resected lymph nodes were the significant prognostic factors. Consequently, early detection and real curative resection with radical lymph node dissection, followed by immunochemotherapy (particularly in patients with stage III gastric cancer) should be recommended as a standard treatment principle for patients with gastric cancer.

Lipid peroxidation inhibitory activity of some constituents isolated from the stem bark of Eucalyptus globulus

Twelve compounds with lipid peroxidation inhibitory activity were isolated from the stem bark of E. globulus. Their structures were assigned as a new aromatic monoterpene (1) and eleven known compounds, pinoresinol (2), vomifoliol (3), 3,4,5-trimethoxyphenol 1-O-beta-D-(6'-O-galloyl)glucopyranoside (4), methyl gallate (5), rhamnazin (6), rhamnetin (7), eriodictyol (8), quercetin (9), taxifolin (10), engelitin (11), and catechin (12) on the basis of UV, mass, and NMR spectroscopic analyses. These compounds except vomifoliol significantly inhibited lipid peroxidation in rat liver microsome.

Antiphotooxidative activity of protoberberines derived from Coptis japonica makino in the chlorophyll-sensitized photooxidation of oil

Antiphotooxidative components were isolated from the methanolic extract of Coptis japonica Makino by liquid-liquid partitioning fractionation, subsequent column chromatography on Sephadex LH-20 and silica gel, and preparative silica gel TLC. The isolated compounds were identified as coptisine, jatrorrizhine, berberine, and magnoflorine by a combination of spectroscopic studies using UV-visible, IR, mass-spectrometry, and NMR. Coptisine, jatrorrizhine, and berberine isolated from Coptis japonica Makino showed strong antiphotooxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. However, these compounds did not show either inhibitory activity against lipid peroxidation in rat liver microsomes nor DPPH radical scavenging activity, indicating that their antiphotooxidative activity was not due to the radical chain reaction breaking ability but due to singlet oxygen quenching activity. Commercially available authentic protoberberines (berberine chloride and palmatine chloride) also showed strong antioxidative activity in the chlorophyll-sensitized photooxidation of linoleic acid. The antiphotooxidative activities of the berberine chloride and palmatine chloride were significantly higher than that of ascorbyl palmitate in the chlorophyll-sensitized photooxidation of linoleic acid. These results clearly showed for the first time the antiphotooxidative properties of protoberberines in chlorophyll-sensitized photooxidation of oil.

Curtisians A-D, new free radical scavengers from the mushroom Paxillus curtisii

In our continuous investigation for free radical scavengers from extracts of fruit body of basidiomycetes, we have isolated four new p-terphenyl compounds, designated as curtisians A-D, from the methanolic extract of the fruit body of Paxillus curtisii. These compounds were isolated by silica gel and Sephadex LH-20 column chromatographies, preparative-TLC and HPLC, consecutively. The structures of curtisians were assigned as p-terphenyls with substituents of acetyl, benzoyl, phenylbutyryl, 3-hydroxybutyryl and 3-acetoxybutyryl. Curtisians A, B, C and D exhibited inhibitory activity against lipid peroxidation with IC50, values of 0.15, 0.17, 0.24 and 0.14 microg/ml, respectively.

Two new genotypes of Plasmodium vivax circumsporozoite protein found in the Republic of Korea

The gene encoding Plasmodium vivax circumsporozoite protein (PvCSP) exhibits polymorphism in many geographical isolates. The present study was designed to investigate polymorphism in PvCSP gene of P. vivax isolates in Korea. Thirty isolates, obtained from indigenous cases in Yonchon-gun, Kyonggi-do in 1997, were subjected for sequencing and RFLP analysis of the repeat and post-repeat regions of PvCSP gene and two genotypes (SK-A and SK-B) were identified. The genotype of 19 isolates was SK-A and that of 11 isolates was SK-B. Although the number of 12-base repeats present in SK-A was three while two were found in a Chinese strain CH-5, the repeat sequence of SK-A was identical to that of CH-5 except for one base substitution. Compared with known data there was no identical isolates with SK-B, but the sequence of SK-B was similar to that of a North Korean (NK) isolate. These results indicate that two genotypes of PvCSP coexist in the present epidemic area of Korea and the present parasite may originate from East Asia. RFLP would be useful to classify genotypes of P. vivax population instead of gene sequencing.

Management of complex breast cysts

OBJECTIVE

This study was undertaken to evaluate the various strategies currently in use to manage complex cysts and specifically address the need for intervention.

MATERIALS AND METHODS

A review of 4562 breast sonograms obtained during an 18-month period revealed 308 complex cysts in 252 women. Data collected from review of patient records included the patient's age and risk factors for breast cancer, aspiration or biopsy results (or both), follow-up imaging studies, and management recommendations.

RESULTS

Management recommendations for complex cysts were 1-year follow-up in 13 patients, 6-month follow-up in 148, sonographically guided aspiration in 82, aspiration with possible core biopsy in 62, and excisional biopsy in three. No malignancies were diagnosed in the group treated with follow-up imaging, sonographically guided aspiration, or excisional biopsy. One malignancy, a papilloma with a 3-mm focus of ductal carcinoma in situ, was diagnosed in one of the patients who underwent core biopsy.

CONCLUSION

Of the lesions classified as complex cysts, the malignancy rate was 0.3% (1/308). This malignancy rate is lower than that for lesions classified as probably benign using mammographic criteria (i.e., for lesions classified as category 3 lesions using the Breast Imaging Reporting and Data System). Because the accepted standard practice for management of probably benign lesions is follow-up studies, the low yield of malignancy in this series suggests that complex cysts can be managed with follow-up imaging studies instead of intervention.

Detection of methylation damage in DNA of gastric cancer tissues using 32P postlabelling assay

Gastric cancer is the most common cancer in Korea. The causes are still unknown but it has been speculated that gastric cancer is associated with consumption of foods rich in nitrates/nitrites or a high dietary intake of salt or pickled food. In the present study, we studied the level of alkylated DNA adducts formed in gastric cancer tissues in comparison with that in normal gastric mucosa. DNA was extracted from surgically removed gastric cancer tissues and patient-matched normal gastric mucosa. The level of N7-methyldeoxyguanosine was measured by 32P-postlabelling assay after high performance liquid chromatography (HPLC) enrichment. We found that the level of N7-methyldeoxyguanosine of gastric cancerous tissues was significantly higher than that of normal gastric mucosa (P=0.01685).

Surgical results in gastric cancer

Although the therapeutic results for gastric cancer have markedly improved, it remains the most common cause of cancer death in Korea. Annually, at Seoul National University Hospital, over 700 gastric cancer patients are surgically treated, and, between the years from 1970 and 1997, a total of 11,491 such patients were treated. We will review the principles of surgery for gastric cancer and our comparative studies of immunochemosurgery and postoperative chemotherapy. Further, we will review our evaluation of the survival rate and prognostic factors for 9,262 patients from 1981 to 1996. We conclude that the most important factors for improvement of the postoperative survival of these patients are early diagnosis and curative resection with radical lymph node dissection, followed by postoperative immunochemotherapy. This should be recommended as the standard treatment for patients with gastric cancer, especially patients with Stage III gastric cancer.

Prognostic factors in 2230 Korean colorectal cancer patients: analysis of consecutively operated cases

To define the prognostic factors in Korean colorectal cancer patients, univariate and multivariate analysis were performed on data from 2230 consecutive patients who underwent resection for colorectal cancer at the Seoul National University Hospital. The prognostic variables used for the analysis included patient's age, gender, bowel obstruction, bleeding, symptom duration, preoperative leukocyte count, preoperative serum carcinoembryonic antigen (CEA) level, Dukes' stage, tumor location, tumor size, depth of bowel wall invasion, number of lymph node metastases, histologic differentiation, and gross morphology of tumor. The overall 5-year survival rate was 62%. In the univariate analysis, all the factors except sex, symptom duration, and tumor size were associated with prognosis. Among the factors significant in the univariate analysis, Dukes' stage (p < 0.001), number of lymph node metastasis (p < 0.001), CEA level (p < 0.001), tumor location (p = 0.003), gross morphology of tumor (p = 0.017), and depth of bowel wall invasion (p = 0.031) were significant in the multivariate analysis. Several differences in prognostic factors between colon cancer and rectal cancer were observed. In the multivariate analysis, gross tumor morphology was significant only for colon cancer, and histologic differentiation was significant only for rectal cancer. Lymph node metastasis was an independent prognostic variable for both colon and rectal cancer, but its significance was more prominent for rectal cancer. Although Dukes' stage is the most reliable prognostic predictor, this study shows that other factors (preoperative CEA level, gross morphology of tumor, location of tumor, nodal status) also provide important information for the outcome of the patient.