Resolution of Ambiguous HLA Genotyping in Korean by Multi-Group-Specific Sequence-Based Typing

PURPOSE: To evaluate a multi-group-specific sequence-based typing (SBT) method for resolving ambiguous results from human leukocyte antigen (HLA) genotyping. MATERIALS AND METHODS: A total of 50 samples that showed ambiguous genotypes for at least two HLA loci from HLA-A, -B, -C and -DRB1 by the conventional SBT assay were evaluated using a new SBT test, the AVITA plus assay. The most likely HLA genotypes for the respective samples considering allele frequencies in Korean were concordant between the AVITA and conventional SBT assays. RESULTS: An average of 3.3 loci among the HLA-A, -B, -C and -DRB1 loci per sample gave results with two or more possible allele combinations with the conventional SBT, and 48 (96.0%) out of 50 showed reduced numbers of possible genotypes for at least one HLA locus with the AVITA. A total of 41, 43, 42, and 38 cases among the 50 samples showed ambiguous results for HLA-A, -B, -C, and -DRB1 typing by the conventional SBT, respectively. The average numbers of possible allele combinations for the respective four HLA loci were 8.2, 6.7, 5.9, and 3.2, and they were reduced to 1.5, 2.2, 4.4, and 1.8, respectively, by the AVITA. Ambiguity was resolved by the AVITA in 33 (80.5%), 31 (72.1%), 17 (40.5%) and 28 (73.7%) samples among the ambiguous cases from the conventional SBT for HLA-A, -B, -C, and -DRB1 typing, respectively. CONCLUSION: The multi-group-specific SBT method considerably reduced the number of ambiguous results, and thus may be useful for accurate HLA typing in clinical laboratories.

Analysis of Clinical Characteristics and S Gene Mutation of Hepatitis B Virus (HBV) in Patients with Hepatitis B Surface Antigen RIA Negative and HBV DNA Positive / 대한진단검사의학회지

BACKGROUND: We investigated hepatitis B virus (HBV) infection cases, who were HBsAg negative by radioimmunoassay (RIA) and HBV DNA positive for their clinical characteristics, the S gene mutation of hepatitis B virus (HBV), and usefulness of other HBsAg immunoassay. METHODS: Among the patients requested for HBV DNA quantification, 16 patients positive in HBV DNA but negative in HBsAg RIA (BNIBT HBsAg Kit, China) were enrolled. The "a" determinant of HBV S gene was sequenced and clinical characteristics were reviewed. Additional HBsAg assay was performed using Architect HBsAg kit (Abbott laboratories, USA) employing chemiluminescent immunoassay method. RESULTS: Eleven of the 16 patients showed multiple mutations in the "a" determinant. These patients received liver transplantation several years ago and have been treated with hepatitis B immune globulin (HBIG) and antiviral drugs. G145R mutation was found in 8 patients and G145K, D144G, and D144A were also frequently found. Among 9 of the 11 patients tested for HBsAg by Architect HBsAg kit, 8 showed positive results. Among 4 of the remaining 5 patients, only 2 showed weak positive results (< or =1 IU/mL) in Architect HBsAg kit. CONCLUSIONS: HBV DNA-positive/HBsAg RIA-negative results were mostly observed in the patients treated with HBIG after liver transplantation, in whom HBIG escape mutations were found. Majority of these cases were positive in Architect HBsAg assay, and it is recommended to use other HBsAg immunoassay methods that are more sensitive than RIA in the detection limit as well as in the detection of escape mutant in hospitals performing liver transplantation.

The K121Q Polymorphism in ENPP1 (PC-1) Is Not Associated with Type 2 Diabetes or Obesity in Korean Male Workers

Type 2 diabetes is characterized by insulin resistance, and ENPP1 plays an important role in insulin resistance. We investigated the association of the ENPP1 K121Q polymorphism with both diabetes and obesity (body mass index [BMI]) in Korean male workers. The study design was case-control. Subjects were 1,945 male workers (type 2 diabetes, 195; non-diabetes, 1,750) of nuclear power plants who received examinations from March to October in 2004. We collected venous blood samples under fasting (> or =8 hr) conditions, calculated BMI by height and weight, and assessed relevant biochemical factors. The results of this study demonstrated that the ENPP1 121Q genotype (KQ+QQ types) was not associated with type 2 diabetes (odds ratios [OR], 0.854; 95% confidence interval [CI], 0.571-1.278) or obesity (OR, 0.933; 95% CI, 0.731-1.190). In addition, the frequency of the Q allele was not related to type 2 diabetes (OR, 0.911; 95% CI, 0.630-1.319) or obesity (OR, 0.962; 95% CI, 0.767-1.205). We concluded that the ENPP1 121Q allele is not a critical determinant for either diabetes or obesity in Korean males. The discordance between the results of this study and those derived from studies of Dominican, South Asian, Caucasian, Finnish, and French populations might be due to differences in genetic backgrounds between these populations.

Co-circulation of Two Genotypes of Hepatitis A Virus from Sporadic Cases in Northeastern Area of Seoul, Korea / 대한진단검사의학회지

BACKGROUND: In previous studies, most hepatitis A virus (HAV) isolates had been genotype IA in Korea. Recently, a small number of different genotypes were reported with an upsurge of acute hepatitis by HAV. We investigated the distribution of HAV genotypes. METHODS: RNA was extracted from anti-HAV IgM positive sera which were collected from March 2007 to February 2008 at a tertiary care hospital in Northeastern Seoul, Korea. Nested reverse transcription (RT)-PCR and direct sequencing for VP1/P2A region of the HAV were performed. RESULTS: A total of 699 cases with suspected acute hepatitis were tested for anti-HAV IgM, and positive results were obtained in 56 sera (8.0%), which were collected 2 to 15 days (median, 7 days)after the onset of symptoms. Of the 56 seropositive samples, 52 (92.9%) were positive for HAV RNA, among which 28 isolates (53.8%) belonged to genotype IA and the remaining 24 (46.2%) belonged to genotype IIIA. Both IA and IIIA genotypes were isolated from 6-7 neighboring administrative districts throughout the year without geographic or seasonal restrictions. CONCLUSIONS: Co-circulation of two distinct HAV genotypes (IA and IIIA) was observed from the northeastern Seoul for the year studied.

Usefulness of PCR-SSP Method for Detection of HLA-DRB1*0405 / 임상검사와정도관리

BACKGROUND: The association between HLA-DRB1 gene and severity of rheumatoid arthritis (RA) has been documented in various reports. Especially, DRB1*0405 allele shows significant association with RA in Korean patients. DRB1*0405 typing has been performed by the sequence based typing method (SBT), that is a difficult and expensive method. So we tried to replace it with a simple and inexpensive method. METHODS: We performed the HLA-DRB1*0405 typing using PCR-SSP technique with sequence specific primers of 3 pair in 298 Koreans. These results were compared with those of high resolution sequence based typing (SBT) method. RESULTS: Of 298 samples typed with the high resolution SBT method, 60 samples were HLA-DRB1*04 positive and showed 9 subgroups of HLA-DRB1*04 and 26 samples were HLA- DRB1*0405 positive. With the PCR-SSP method, same 26 samples were HLA-DRB1*0405 positive, showing 100% correspondence between two methods to detect HLA-DRB1*0405 CONCLUSIONS: Using PCR-SSP method to type HLA-DRB1*0405 is a very useful tools for studying the association between rheumatoid arthritis and HLA-DRB1*0405 from a practical and economic view.

Performance Evaluation of Real-Q HBV Quantification Kit for HBV DNA by Real-Time PCR / 대한진단검사의학회지

BACKGROUND: Hepatitis B virus (HBV) DNA quantification is important for the management of HBV infection and identification of the development of resistance. The susceptibility to contamination and more variable reproducibility of results with the conventional HBV DNA quantification method have raised the need of a more simple and accurate method for HBV DNA quantification. Real-time quantitative PCR assays recently introduced in the laboratory can meet these needs. In this study, we evaluated the performance of the Real-Q HBV Quantification kit developed in Korea. METHODS: We evaluated the recovery of DNA extraction, the interference of internal control, an analytical sensitivity, specificity, and reproducibility, a clinical specificity, and a reportable range of the Real-Q HBV Quantification kit. The quantification result was also compared to that obtained by the Digene Hybrid-Capture II. RESULTS: The mean percent recovery was 108.6% and there was no interference with the internal control on DNA extraction. None of HIV, hepatitis C virus, or cytomegalovirus showed a cross-reactivity with HBV. This assay detected HBV DNA in a linear range from 10(2) to 10(10) copies/mL, with the detection limit of 56 copies/mL. The assay exhibited a low within-run CV (coefficient of variation) (8.7-11.9%), between-run CV (10.5-14.7%), and between-day CV (13.2-21.4%). No HBV DNA was detected in any of 100 samples without HBV, resulting in a clinical specificity of 100%. The levels of HBV DNA showed a good correlation with those determined with Digene Hybrid-Capture II (R2=0.9827). CONCLUSIONS: The Real-Q HBV Quantification kit showed a good analytical sensitivity, specificity, and high reliability with a broad reportable range. This assay should be clinically useful in managing patients with HBV infection.

Evaluation of Self-collected Pad Sampling for the Detection of HPV In Cervicovaginal Secretion

BACKGROUND: Self-collection of secretion samples for HPV testing is a feasible alternative method for women who would decline to participate in population based cervical cancer programs. The purpose of this study was to determine the sensitivity and specificity of self-sampling for HPV in determining high grade squamous intraepithelial lesion (HSIL) using the pad, and we also wished to compare the results from samples collected by women themselves and those results from samples collected by physicians. METHODS: Fifty patients voluntarily participated in the sensitivity and specificity study at the university hospitals and 290 volunteers participated in the agreement study at local clinics. DNA was extracted and amplified using HPV L1 consensus primers for the direct sequencing of the pad samples. RESULTS: For the detection of HSIL, self-collected pad sampling showed good sensitivity (75.0%) and excellent specificity (100%). Two hundreds eighty-six samples from the pads and concurrent physicians?samples showed the agreement at 98.6% with the Kappa, 0.9622 (p=0.0000). CONCLUSIONS: A self-sampling method using the pad for the detection of HPV DNA is suggested to be an efficient method to access many women for screening easily, rapidly and conveniently. Testing the pad method? utility for a country- or large area-based mass screening study will be necessary in the future.

Distribution of HLA-A, B, C Allele and Haplotype Frequencies in Koreans / 대한진단검사의학회지

BACKGROUND: The HLA system is known to be the most polymorphic gene cluster in the human genome. HLA allele and haplotype distribution varies widely among different ethnic groups. In this study, we examined the frequency of HLA class I alleles and haplotypes in 309 healthy Koreans. METHODS: We typed HLA-A, -B, and -C genes at the allelic level in 109 unrelated Korean individuals using a sequence-based typing. With the additional data of 200 healthy Koreans from dbMHC (http: //www.ncbi.nlm.nih.gov/mhc/), allele and haplotype frequencies were estimated by the maximum likelihood method. Serological typing results of 49 individuals were compared with the results highly resolved. RESULTS: A total of 22 HLA-A, 41 HLA-B, and 21 HLA-C alleles were found in this study. Alleles showing frequencies of more than 10% in each HLA locus were A*2402 (22.5%), A*0201 (15.7%), A*3303 (14.4%), A*1101 (11.0%), B*5101 (12.1%), Cw*0102 (18.8%), and Cw*1402 (10.2%). The most common A-B-C haplotypes at a frequency of more than 3% were A*3303-B*5801-Cw*0302 (5.2%), A*2402-B*5101-Cw*1402 (4.5%), A*1101-B*1501-Cw*0401 (4.3%), A*3303-B*4403-Cw*1403 (4.0%), A*3001-B*1302-Cw*0602 (3.7%), and A*0207-B*4601-Cw*0102 (3.2%). Misassignment of HLA-C antigen by serotyping was detected in 11 (22.4%) of 49 individuals. CONCLUSIONS: Our results will be useful as a basic data for studies on anthropology, disease association, and bone marrow transplantation. Misidentification of HLA-C by serotyping is so high that it would be desirable to perform a DNA typing especially in unrelated bone marrow transplantation.

Chronological Changes of Gastric Cancer in Community Hospital

PURPOSE: Gastric cancer remains the most common type of cancer in Korea, however, early diagnosis and surgical advancements have resulted in a better prognosis in the last few decades. The aim of this study was to investigate chronological changes of the clinicopathological features in patients with primary gastric cancer who had undergone gastric operations in Department of Surgery of Seoul Municipal Boramae Hospital. METHOD: Between November 1991 and April 2001, 634 primary gastric adenocarcinoma patients having undergone gastric operations were included in this study and divided into the two groups: 298 patients between 1991 and 1996 (early group) and 336 patients thereafter (late group). The clinicopathological characteristics, including age, gender, type of operation, gross and histologial findings, stage, and ratio of early gastric cancer, were compared between the two groups. RESULTS: The overall male-to-female ratio was 2: 1, with a mean age of 59.0 years. As the community hospital, eighty two percents of patients were resident within the same administrative district. There were no statistical differences in age, gender, type of operation, and total number of resected lymph nodes between the two groups. In contrast, cancers with a larger size, the distal one third of the location, well-differentiated adenocarcinoma, low depth of invasion, and high nodal metastasis were more prevalent in the late group (P < 0.05). Also, the proportion of earlier stages was increased in the late period (P<0.001). The ratios of early gastric cancers were 24.8, and 38.4% in the early and late groups, respectively (P<0.001) CONCLUSION: Our results suggest that the chronological changes of gastric cancer were closely related to the increased number of early gastric cancer patients, primarily due to the early detection of cancer. Therefore, to obtain the better outcomes from gastric cancer, an early diagnosis was essential from routine health check-ups and the well- organized establishment of a nation- and community-wide screening program and information on public health.

A therapeutic Guideline of Gallbladder Polyps in Laparoscopic Era / 한국간담췌외과학회지

BACKGROUND/AIMS: The nature of gallbladder polyp is obscure before operation, and surgical indication is still controversial. The aim of this study is to suggest the therapeutic guideline for patients with the gallbladder polyps in the laparoscopic era. METHODS: Among 49 patients who received cholecystectomy because of gallbladder polyp from January 1, 1992 to December 31, 2000 in Department of Surgery, Seoul Municipal Boramae Hospital, we studied 42 histopathologically confirmed gallbladder polyp patients retrospectively. These patients were divided into two groups as true polyp(adenoma, carcinoma) and pseudopolyp(cholesterol, inflammatory, hyperplastic), and clinical characteristics were compared between the groups. RESULTS: The mean age was 48.19+/-11.09 years and male to female ratio was 17:25 in all patients. Of 42 patients, 32 pseudopolyps(76.2%) and 10 true polyps(23.8%) were confirmed by pathologic examination. Of 32 pseudopolyps, cholesterol polyps(29cases, 90.6%) were most common type. 4 carcinomas and 6 adenomas were included in 10 true polyps. Of 6 adenomas, coexistence with dysplasia was present in two cases. 1 case of carcinoma was present as arising from underlying tubular adenoma. Compared with pseudopolyp, true polyp showed significant larger size in diameter than psedopolyp(p=0.014). Despite of these statistical difference, 44% of pseudopolyps was more than 10mm in maximum diameter. 2 cases of true polyp(20%) was less than 10mm. However all of the other clinical features such as, the patients's age, sex, symptom, presence of gallstones, and number of polypoid lesion were not significantly different between the groups. All 4 carcinoma patients received laparoscopic cholecystectomy are disease free state with mean 68.5 months follow-up period. CONCLUSION: Although true polyps showed statistically significant larger than pseudopolyps in maximum diameter, there was no clear cut point dividing the two groups. All of the other clinical characteristics could not differentiated true polyps from pseudopolyps. Because of the low morbidity of laparoscopic procedure, premalignant potential of gallbladder adenoma and the adenoma-carcinoma sequence are unquestionable, an aggressive surgical intervention should be proposed in the era of laparoscopic surgery.

A Guideline on the Removal Time of the Nasogastric Tube Following Gastrectomy

PURPOSE: There is no standard principle as to the nasogastric tube decompression period following gastrectomy. This prospective randomized study was done in an attempt to define the affect of the nasogastric tube decompression period on the postoperative course with a special reference to early postoperative complications, gas passing time, and the length of hospital stay after gastrectomy. METHODS: We reviewed 201 patients among 402 cases who had received gastrectomy because of gastric cancer. The patients were classified as those whose tubes were removed within 48 hours postoperatively, and those whose tubes remained for more than 48 hours (early group: n=70, late group: n=131). RESULTS: No significant differences were noted in regards to complication rate, or hospital stay. However, a significant decrease in the time to first gas passing was noted in the early removal group compared to late group (4.13+/-1.33 day vs. 4.39+/-1.50 day, P=0.040). CONCLUSION: These results indicate that the early removal of the nasogastric tube following gastrectomy is safely recommended in order to reduce patient discomfort.

A Porcine Model for Non-heart Beating Donor Liver Transplantation / 대한이식학회지

PURPOSE: Non-heart-beating liver transplantation has been accepted as a substitute to overcome the donor shortage problem. However, prolonged warm ischemia during liver procurement remains a obstacle to widespread use of non- heart-beating transplantation. Therefore, experimental studies to ameliorate graft injuries have been conducted, but, their clinical applications are not satisfactory yet. The aim of this study is to test our experimental model as a pertinent non- heart-beating transplantation model. METHODS: We designed porcine non-heart-beating liver transplantation model by simultaneous liver procurement of donor and recipient. Cardiac death was induced by direct cardiac injection of potassium chloride. Perfusion of normothermic hypertonic saline started after 30-min (group A, N=5), 1-hour (group B, N=4). Orthotopic liver transplantation with perfused donor liver was performed and we compared the perioperative laboratory parameter, histologic findings and survival between two groups. RESULTS: Only one (11.1%) death occurred among the nine transplant pigs. 2-day survival rates of group A and B were 60%, 50%, respectively. Group A showed a relatively acceptable posttransplant laboratory findings including liver function test and normal-looking histologic feature at the time of reperfusion and 24 hours after reperfusion. Group B showed more deranged liver function test and ischemic liver cell morphology at 24 hours after reperfusion. CONCLUSION: Our results suggest that this porcine non-heart-beating transplantation model may be the safe and suitable method. This model will be useful in further study for testing the perfusate and drugs to ameliorate the warm ischemia-induced hepatic injury.

Risk Factors of Portal Vein Invasion in Hepatocellular Carcinoma

BACKGROUND: The long-term prognosis of patients with hepatocellular carcinomas is still disappointing primarily because of intrahepatic recurrence. Among many factors, portal vein invasion is considered to be the most important risk factor leading to recurrence, and it is thought to be the direct evidence of tumor invasiveness. In clinical aspects, it seems to be more practical to determine the factors associated with portal vein invasion. METHODS: Three hundred and seventy-one patients who underwent a curative hepatic resection for hepatocellular carcinomas between 1991 and 1995 at Seoul National University Hospital were included in this study. Portal vein invasion was identified histopathologically. The prognostic factors of hepatocellular carcinoma and the risk factors linked to portal vein invasion were analyzed by both univariate and multivariate analyses. RESULTS: Portal vein invasion was detected in thirty seven patients (10%), and the 5-year overall and disease-free survival rates in this group were 39.9% and 6.5%, respectively. The 5-year overall and disease-free survival rates of patients without portal vein invasion were 60.1% and 36.8%, respectively. In multivariate analysis using Cox's proportional hazards model, portal vein invasion was proven to be the most important risk factor in both overall and disease-free survival. In a multiple stepwise logistic regression analysis, the size and the number of the tumors were strong independent predictors of portal vein invasion by a hepatocellular carcinoma. CONCLUSIONS: Intrahepatic recurrence and patient survival in cases of hepatocellular carcinomas were closely related to portal vein invasion. Patients with tumor sizes larger than 4 cm or with multiple tumors should be monitored closely for early recurrence.

The Diagnostic Accuracies of Fine Needle Aspiration Biopsy, Mammography and Ultrasonography in Palpable Breast Mass

BACKGROUND: Although an increasing number of breast abnormalities are detected by screening mammography, most breast cancers are presented as a palpable mass. Cytologic specimens are frequently diagnostic and may be easier to obtain. This study was done to compare the diagnostic accuracies of clinical breast exam, fine needle aspiration biopsy (FNAB), mammography and ultrasonography, and to establish the algorithm to manage the patients based on the results of FNAB. METHODS: From Jan. 1992 to Dec. 1997, one hundred and twenty-seven women out of 470 patients with a clinically palpable mass underwent concurrent FNAB, mammography, and ultrasonography. All patients ultimately had histologic confirmation by surgical biopsy. RESULTS: The sensitivity and the specificity of the tests were as follows: 79.2% and 74.4%, respectively, for clinical breast exam; 62.2% and 98.6%, for mammography; 55.8% and 93.3% for ultrasonography; and 66.7% and 100% for FNAB. Of note, the accuracy of the FNAB was significantly higher for lesions 2 cm or larger than for lesions smaller than 2 cm (p=0.034). All patients who were positive for malignancy on FNAB (n=20) presented with breast cancer. Among the 16 patients with suspicious results on FNAB and breast cancer on surgical biopsy, 3 had normal findings on mammography and ultrasonography. In the cases of negative findings for malignancy in three tests (n=55), no breast cancer was found on the final surgical specimen. CONCLUSION: It is recommended that FNAB must be performed on all palpable masses and that when the FNAB is postive for cancer, definitive surgery be performed with intraoperative frozen biopsy. Patients in whom mammography, ultrasonography and FNAB were negative for malignancy can be observed without the need for an open biopsy. Additionally, (1) when the results of FNAB are suspicious or (2) when the mammagraphy and ultrasonography results are suspicious even though the FNAB results are negative for malignancy, an open biopsy is required to exclude the possibility of the breast cancer.

Endocrine Tumors of the Pancreas Secreting Multiple Hormones / 대한내분비학회지

BACKGROUND: Endocrine pancreas tumor is a rare disease which incidence is less than 2% of all pancreatic tumors. But it comprises various types of tumor and usually secretes several hormones from one type of tumor although the patient with this tumor complains of sole symptom associated with only one hormone. The mechanism and clinical significance of multiple hormone secretion in the endocrine pancreas tumom are not yet clearly defined. METHODS: We analyzed retrospectively the clinicopathologic features of 20 cases which were operated at Seoul National University Hospital during the period between February 1989 and May 1998. RESULTS: The most common tumor was insulinoma (13 cases) and the second most common tumor was nonfunctioning tumor (6 cases). There was one case of somatostatinoma. Most of the patients with insulinoma complained of neuroglycopenic symptoms. There were 9 cases (45.0%) in which the tumors secreted more than two kinds of hormones, 7 cases in insulinoma, 2 cases in nonfunctioning tumors. Whether the tumor secreted multiple hormones was detected by the method of immunohistochemical staining. Though the tumors secreted more than two kinds of hormones, the patients with the tumors complained of symptoms which were associated with the cell type most strongly stained by immunohistochemical method. Whether or not the tumors secreted multiple hormones was not associated with the pathologic features such as tumor size, histologic patterns of the tumor, status of tumor cell differentiation and malignancy. CONCLUSION: From this results, we suggest that endocrine tumors of the pancreas secreted multiple hormones not by the mechanism of dedifferentiation from already differentiated endocrine cells but by the mechanism of neogenesis of multipotent islet stem cells. Since the relationship between the function of multiple hormone secretion in the endocrine pancreas tumors and islet stem cell would be significant, further study should be needed to find out the function of stem cells and application of stem cells to clinical use.

The Predictors of Axillary Node Metastasis in 2 cm or Less Breast Cancer / 대한암학회지

PURPOSE: Axillary node involvement is the single most important prognostic variable in patients with breast cancer. If axillary lymph node status of breast cancer patients could be accurately predicted from basic clinical information and from characteristics of their primary tumors, many patients could be spared axillary lymph node dissection. With the availability of numerous histologic prognosticators and new immunochemical prognostic indicators, it is reasonable to reconsider the necessity of axillary node dissection for lesions more advanced than duct carcinoma in situ. MATERIALS AND METHODS: Six hundred fifty-six patients with Tl invasive breast cancer were evaluated. All the patients underwent axillary dissection, and the pathologic status of the nodes was known. The parameters of the primary tumor in this study were age, size, family history, tumor palpability, nuclear and histological grade, hormone receptor status, lymphatic vessel invasion (LVI), and various tumor markers (bc1-2, cathepsinD, c-erbB2, E-cadherin, p53). RESULTS: Approximately 31% of the 656 patients with Tl breast carcinoma had axillary node metastasis. Four factors were identified as significant predictors of node metastasis: age 35 or less (p=0.01), lymphatic vessel invasion (p < 0.01), tumor palpability (p=0.02), and tumor size (p<0.01). However, independent predictors of lymph node metastasis in the multivariate logistic regression analyses were tumor size (p=0.04) and LVI (p=0.03). CONCLUSION: Characteristics of the primary tumor can help assess the risk for axillary lymph node metastases in Tl breast cancer. Selected patients who have 1cm or less without lymphatic vessel invasion are considered to be at minimal risk of axillary node metastasis and might be spared routine axillary dissection.

The Result of Surgical Treatment of Complicated Peptic Ulcers: Analysis of Factors Affecting the Morbidity Rate

BACKGROUNDS: The aim of this retrospective study was to compare patients treated for complicated peptic ulcers with special reference to the morbidity and the mortality rates and its determining factors according to the type of surgery. METHODS: From Jan. 1988 to May 1996, a total of 168 patients with complicated peptic ulcers underwent surgical treatment. Among them, 39 patients were lost during the follow up period and 10 cases were operated on due to pyloric obstruction, so we analyzed 119 cases according to the type of surgery (definitive or minimal). Definitive surgery means acid-decreasing procedures such as a gastrectomy or a truncal vagotomy with drainage procedure. Minimal surgery means life-saving procedures such as primary closure or bleeding vessel ligation. The type of operation was determined according to the preference of the individual consultant surgeons at our institute. RESULTS: There were 70 definitive and 49 minimal operations (6:4). The mean follow-up period was 20.6 months (range: 11-73 months). The risk factors affecting the morbidity and the mortality were comparable for both groups. In spite of little statistical significance, the results of definitive surgery were superior to those of minimal surgery in morbidity (15.7%:20.4%), mortality (0%:6.1%), recurrence (5.5%:12.2%), and Visick grading scale 1 & 2 (92.8%:81.6%). The determining factor affecting morbidity was the presence of combined disease (p=0.001) only; other factors such as age, anemia, leukocytosis, presence of preoperative shock, transfusion amount, and type of operation did not affect the morbidity rate. CONCLUSION: Considering that there were no differences in postoperative morbidity and mortality between definitive and minimal surgery, it is better to perform definitive surgery on patients who have no serious combined disease.

A Clinical Analysis of Stage IV Gastric Cancer

From 1988 to 1994, 62 of 262 patients admitted to the Boramae City Hospital with gastric cancer were diagnosed as stage IV. Among them, 5 patients were lost during follow-up, so we analyzed 57 patients retrospectively. This study elucidates whether a palliative resection offered any survival advantage compared to non-resectional treatment. Of the 57 patients, 7 (12%) received a non-curative resection, 36 (63%) a bypass procedure, and 14 (25%) an exploratory laparotomy. There were no operative mortalities and morbidity. Univariate survival analysis demonstrated that the median survival and the 1- and the 2-year survival rates were significantly higher in the resected patients. The median survival and the 1- and the 2-year survival rates were 15 months, 71%, and 57% with a non-curative resection, 7.3 months, 25%, and 8% with bypass procedure, and 6.3 months 33%, and 17% with an exploratory laparotomy. To perform the analysis within relatively homogeneous groups, patients with different operations were further stratified into two groups according to the spread of disease: local (T4) and distant (M1) spread. The median survival of the T4 group was 11.4 months whereas that of the M1 group was 6 months. Although there was no statistical significance in this study, it is noteworthy that, compared to a bypass procedure and a exploratory laparotomy, a non-curative resection seems to have a survival benefit in the M1 group (median survival: 528 days vs 131 days and 182 days, p=0.0926). In conclusion, although this study has the limitations of a retrospective study and a univariate analysis performed without consideration of basic patient characteristics (age, weight loss, nutritional status, etc.), palliative resection seems to be justified in patients with stage IV gastric cancer if it is performed with acceptably low mortality and morbidity.

Complications of Dual Lumen Catheter for Hemodialysis Patients

INTRODUCTION: Central venous catheterization by dual lumen catheter (DLC, Perm Cath ) is used for temporary or permanent vascular access. Although it has many advantages such as rapid insertion, emergent usage or long-term maintenance, there are still clinically important complications associated with insertion procedure and maintaining period. PURPOSE: To define and manage the various kinds of complications is important to avoid repetition of them and to guide for selection of vascular access in long-term hemodialysis patients. MATERIALS AND METHODS: Between May 1993 and April 1996, we experienced 95 cases of DLC in 88 uremic patients for the following reasons: 12 cases in 12 patients for ARF and 83 cases in 76 patients for ESRD. We used external or internal jugular veins and the method of insertion was percutaneous venipuncture in internal jugular vein (88 cases, Rt.=84, Lt.=4) and venotomy in external jugular vein (7 cases Rt=7). The complications and their therapeutic options were analyzed retrospectively. RESULTS: Group I complication is associated with insertion procedure, including cardiac arrhythmia (n=65, 68.4%), minor air embolism (n=3, 3.2%), hematoma on puncture site (n=15, 15.8%) and difficult catheterization on multipunctured patients (n=3, 3.2%). Group II complication is associated with long term maintanence use of catheters(mean period=8.3 mos) and includes catheter thrombosis (n=15, 15.8%), inadvertent cuff exposure (n=10, 10.5%) and bacteremia (n=16, 16.6%). The management of complications were as followings. Cardiac arrhythmia occurred during guidewire insertion was completely resolved with wire retraction and clinically detected minor air embolism was recovered spontaneously in all cases. Hematoma on puncture site was controlled by compression in 13 cases and 2 cases were resolved after catheter removal. All of the difficult catheterization was solved with fluoroscopic guide insertion. Most of catheter thrombosis were controlled with urokinase infusion (n=13), but in 2 cases, catheter removal was required. All cases of inadvertent cuff exposure led to ascending infection, among them 6 cases were controlled with catheter removal and the rest of them was controlled with aseptic dressing and antibiotics. Five out of 16 cases (5.3%) with bacteremia were not controlled with antibiotics and resulted in catheter removal. CONCLUSION: To avoid unfavorable complications such as uncontrolled hematoma or bacteremia, fluoroscopic guide insertion and aseptic handling of exit site is important. And it should be remembered that location of cuff should be far from the exit site (> 2 cm) to avoid inadvertent traction.

Menstrual and reproductive factors related to the risk of breast cancer in Korea: Ovarian hormone effect on breast cancer

To support the ovarian hormone hypothesis in the etiology of breast cancer, a hospital-based case-control study with community controls was conducted to evaluate the relationship of intervals among menstrual and reproductive events to the risk of breast cancer in Korea. The cases were 190 breast cancer patients, who had been histologically diagnosed at Seoul National University Hospital from Jan. 1, 1993 to Jun. 30, 1994. Included were cancer-free women, who had undertaken the Gynecological examination at the same hospital (n=190). Women recruited for a survey of diabetes prevalence in Yonchon County, adjacent to Seoul City, were taken as a community control group (n=190). Information on menstrual and reproductive factors with other life-styles was collected through a direct interview by the well-trained interviewers. The adjusted odds ratios and the 95% confidence intervals were based on the unconditional logistic regression model. Likelihood ratio test for trend was applied for the ordinal variables. Early age at menarche, late age at natural menopause, late age at first full term pregnancy, and fewer number of full term pregnancies are independently associated with the high risk of breast cancer in Korea. Moreover, the interval between the age at menarche and the age at natural menopause of community controls (29.9+/-6.15 years) was significantly shortened compared to breast cancer cases (34.9+/-4.42 years). Particularly noteworthy was that intervals between the age at menarche and the age at first full term pregnancy of both control groups (9.0+/-3.72 years for hospital controls; 7.2+/-4.04 years for community controls) were significantly shortened compared to breast cancer cases (11.0+/-4.51 years). These findings support the hypothesis that the longer exposure to ovarian hormones during the reproductive years, the higher the risk of breast cancer.