Is elective nodal irradiation beneficial in patients with pathologically negative lymph nodes after neoadjuvant chemotherapy and breast-conserving surgery for clinical stage II-III breast cancer? A multicentre retrospective study (KROG 12-05)

BACKGROUND

To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II-III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT).

METHODS

We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated.

RESULTS

After a median follow-up period of 66.2 months (range, 15.6-127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0-is vs 1 vs 2-4) and the number of LNs sampled (<13 vs ≥13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled.

CONCLUSIONS

ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials.

Characterization of Lactic Acid Bacteria Isolated from Sauce-type Kimchi

This study was carried out to investigate the isolation and characterization of lactic acid bacteria (LAB) from naturally fermented sauce-type kimchi. Sauce-type kimchi was prepared with fresh, chopped ingredients (Korean cabbage, radish, garlic, ginger, green onion, and red pepper). The two isolated bacteria from sauce-type kimchi were identified as Pediococcus pentosaceus and Lactobacillus brevis by 16S rDNA sequencing and tentatively named Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2, respectively. Pediococcus sp. IJ-K1 was isolated from the early and middle fermentation stages of sauce-type kimchi whereas Lactobacillus sp. IJ-K2 was isolated from the late fermentation stage. The resistance of Pediococcus sp. IJ-K1 and Lactobacillus sp. IJ-K2 to artificial gastric and bile acids led to bacterial survival rates that were 100% and 84.21%, respectively.

Diffusion-weighted MRI for differentiation of benign from malignant lesions in the gallbladder

AIM

To investigate the value of diffusion-weighted imaging (DWI) for differentiating benign from malignant gallbladder lesions.

MATERIALS AND METHODS

One hundred and twenty-six patients who had undergone magnetic resonance imaging (MRI) with DWI, in whom the histopathological diagnosis of their gallbladder lesions was confirmed by biopsy or surgery were retrospectively analysed. Thirty-six malignant and 90 benign lesions were included. Two radiologists categorized gallbladder lesions into seven types on two imaging sets [T2-weighted imaging (WI) alone and combined T2WI and DWI (b = 800 s/mm(2))] according to the presence of wall thickening, layered patterns, morphology of the mass, and diffusion restriction. Disagreements were resolved in consensus. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging set for diagnosing gallbladder carcinoma were calculated. The diagnostic performance of each imaging set was calculated using receiver operating characteristic (ROC) curve analysis. Additionally, ADC values of malignant and benign gallbladder lesions were compared separately for 1.5 and 3 T MRI.

RESULTS

The sensitivity, specificity, PPV, and NPV of diagnosis at T2WI were 97.2%, 86.7%, 74.5%, and 98.7%, respectively. The sensitivity, specificity, PPV, and NPV using combined T2WI and DWI were 97.2%, 92.2%, 83.3%, and 98.8%, respectively. Diagnostic accuracy for gallbladder carcinoma slightly improved after adding DWI, from 0.92 to 0.95 (p < 0.05). ADC values for gallbladder carcinoma were significantly lower than those for benign lesions. Mean ADC values of malignant and benign lesions were 0.97 ± 0.25 × 10(-3) and 1.72 ± 0.56 × 10(-3) mm(2)/s, respectively, at 1.5 T (p < 0.001), and 1.04 ± 0.38 × 10(-3) and 2.2 ± 0.72 × 10(-3) mm(2)/s, respectively, at 3 T (p < 0.001).

CONCLUSION

DWI can improve diagnostic accuracy for differentiating benign from malignant gallbladder lesions.

MDCT features in the differentiation of T4a gastric cancer from less-advanced gastric cancer: significance of the hyperattenuating serosa sign

OBJECTIVE

The purpose of our study was to evaluate CT findings to differentiate between T4a and less advanced gastric cancers.

METHODS

The institutional review board approved this study and waived informed consent. This study included 228 retrospectively identified patients with surgically confirmed gastric cancer (138 T1, 25 T2, 24 T3 and 41 T4a) and who had also undergone pre-operative CT scan. Transverse and multiplanar reconstruction scans were reviewed in consensus by two other blinded radiologists. The following CT findings that differentiate T4a from less advanced cancers were evaluated: nodular or an irregular outer layer of the gastric wall, haziness of the perigastric fat and a hyperattenuating serosa sign. The CT features of T4a and less advanced gastric cancers were compared by means of univariate and multivariate analyses.

RESULTS

In univariate analysis, nodular or an irregular outer layer of the gastric wall, haziness of the perigastric fat and the hyperattenuating serosa sign were significant in differentiation between T4a and less advanced gastric cancers. In addition, nodular or an irregular outer layer of the gastric wall and the hyperattenuating serosa sign were significant in differentiation between T3 and T4a. In multivariate logistic analysis, the hyperattenuating serosa sign was the most significant finding in differentiation between T3 and T4a (odds ratio, 4.210; 95% confidence intervals, 1.581-11.214; p=0.004).

CONCLUSION

The hyperattenuating serosa sign may be a useful CT finding in differentiation between T4a and less-advanced gastric cancers.

ADVANCES IN KNOWLEDGE

The hyperattenuating serosa sign is associated with gastric cancer with invading the serosa and can facilitate planning of the optimal pre-operative evaluation and treatment.

The relationship between mast cell density and tumour grade in transitional cell carcinoma of the bladder

This study investigated the relationship between mast cell numbers and the grade of bladder transitional cell carcinoma (TCC). Bladder TCC biopsies were obtained via transurethral resection and 45 stage T1 specimens were included in the study. Specimens were sorted into two groups, low grade (grade I) and high grade (grades II and III). Samples were stained using haematoxylin and eosin, toluidine blue and immunohistochemical staining for tryptase. Mast cells were examined by light microscopy and cell density was recorded. Mast cell density was significantly higher in high-grade TCC than low-grade TCC. There was also a significant relationship between the number of mast cells identified using toluidine blue staining or immunohistochemical staining for tryptase. Detailed studies of mast cell function will enable the development of more effective antitumour therapies via mast cell manipulation.

Interspecies interaction of signal peptide PapR secreted by Bacillus cereus and its effect on production of antimicrobial peptide

This study was carried out to investigate the interspecies interaction of PapR peptide secreted by Bacillus cereus on production of BSAP-254, an antimicrobial peptide produced by Bacillus subtilis SC-8 isolated from the Korean fermented soybean paste and exhibited narrow antagonistic activity against the B. cereus group, but not against other foodborne pathogens. PapR is a signal peptide that activates PlcR, which is a pleiotropic regulator controlling the expression of various virulence factors in B. cereus. When B. subtilis SC-8 was co-cultured with B. cereus, it completely inhibited the growth of B. cereus within 12 h, and the rate of BSAP-254 production was increased 34.2% at 12 h. Furthermore, 5 μM of synthetic PapR peptide added to the culture of B. subtilis SC-8 increased the rate of BSAP-254 production up to 59.7%. The growth of B. subtilis SC-8, however, was not significantly different with or without the addition of PapR. When B. cereus papR mutant was co-cultured with B. subtilis SC-8, the growth of the mutant was not inhibited and the rate of BSAP-254 production was decreased by 45%.

Genome sequencing of Bacillus subtilis SC-8, antagonistic to the Bacillus cereus group, isolated from traditional Korean fermented-soybean food

Bacillus subtilis SC-8 is a Gram-positive bacterium displaying narrow antagonistic activity for the Bacillus cereus group. B. subtilis SC-8 was isolated from Korean traditional fermented-soybean food. Here we report the draft genome sequence of B. subtilis SC-8, including biosynthetic genes for antibiotics that may have beneficial effects for control of food-borne pathogens.

CT differentiation of pyogenic liver abscesses caused by Klebsiella pneumoniae vs non-Klebsiella pneumoniae

OBJECTIVE

Klebsiella pneumoniae is one of the organisms most commonly isolated from pyogenic liver abscesses in Asian populations. We compared CT findings in liver abscesses caused by K. pneumoniae with those caused by other bacterial pathogens.

METHODS

Of 214 patients with liver abscesses examined over a 5 year period, 129 patients with positive blood or aspirate cultures were enrolled. The patients were divided into two groups: the K. pneumoniae monomicrobial liver abscess (KLA) group (n = 59) and the non-K. pneumoniae monomicrobial or polymicrobial liver abscess (non-KLA) group (n = 70). Two radiologists blinded to the culture results evaluated the CT images, recording the number, size, location and configuration of abscesses, the thickness of the abscess wall, the pattern of rim enhancement, septal enhancement, the double target sign, internal necrotic debris, internal gas bubbles and underlying biliary disease. The presence of diabetes and metastatic infection was also compared between groups. Statistical analyses were performed using univariate (Student's t-test and χ(2) test) and multivariate analyses.

RESULTS

Multivariate analysis showed that a thin wall, necrotic debris, metastatic infection and the absence of underlying biliary disease were the most significant predictors of KLA. When three of the four criteria were used in combination, a specificity of 98.6% was achieved for the diagnosis of KLA.

CONCLUSION

A thin-walled abscess, internal necrotic debris, the presence of metastatic infection and the absence of underlying biliary disease may be useful CT findings in the early diagnosis of K. pneumoniae liver abscesses.

Isolation and characterization of a novel analyte from Bacillus subtilis SC-8 antagonistic to Bacillus cereus

In this study, an effective substance was isolated from Bacillus subtilis SC-8, which was obtained from traditionally fermented soybean paste, cheonggukjang. The substance was purified by HPLC, and its properties were analyzed. It had an adequate antagonistic effect on Bacilluscereus, and its spectrum of activity was narrow. When tested on several gram-negative and gram-positive foodborne pathogenic bacteria such as Salmonella enterica, Salmonella enteritidis, Staphylococcus aureus, and Listeria monocytogenes, no antagonistic effect was observed. Applying the derivative from B. subtilis SC-8 within the same genus did not inhibit the growth of major soybean-fermenting bacteria such as Bacillus subtilis, Bacillus licheniformis, and Bacillus amyloquefaciens. The range of pH stability of the purified antagonistic substance was wide (from 4.0 to >10.0), and the substance was thermally stable up to 60 degrees C. In the various enzyme treatments, the antagonistic activity of the purified substance was reduced with proteinase K, protease, and lipase; its activity was partially destroyed with esterase. Spores of B. cereus did not grow at all in the presence of 5mug/mL of the purified antagonistic substance. The isolated antagonistic substance was thought to be an antibiotic-like lipopeptidal compound and was tentatively named BSAP-254 because it absorbed to UV radiation at 254nm.

Measuring the kinetics of biomolecular recognition with magnetic colloids

We introduce a general methodology based on magnetic colloids to study the recognition kinetics of tethered biomolecules. Access to the full kinetics of the reaction is provided by an explicit measure of the time evolution of the reactant densities. Binding between a single ligand and its complementary receptor is here limited by the colloidal rotational diffusion. It occurs within a binding distance that can be extracted by a reaction-diffusion theory that properly accounts for the rotational Brownian dynamics. Our reaction geometry allows us to probe a large diversity of bioadhesive molecules and tethers, thus providing a quantitative guidance for designing more efficient reactive biomimetic surfaces, as required for diagnostic, therapeutic, and tissue engineering techniques.

[Restriction polymorphism of mitochondrial DNA in Koreans and Mongolians]

Using the data on mitochondrial DNA (mtDNA) restriction polymorphism, the gene pools of Koreans (N = 164) and Mongolians (N = 48) were characterized. It was demonstrated that the gene pools were represented by the common set of mtDNA haplogroups of East Asian origin (M*, M7, M8a, M10, C, D4, G*, G2, A, B*, B5, F1, and N*). In addition to this set, mtDNA haplogroups D5 and Y were identified in Koreans while Mongolians possessed haplogroup Z. Only in Mongolians, a European component with the frequency of 10.4% and represented by the mtDNA types belonging to haplogroups K, U4, and N1, was identified. Phylogenetic and statistical analyses of the data on mtDNA variation in the populations of South Siberia, Central, and East Asia suggested the existence of interpopulation differentiation within these regions, the main role in which was played by the geographical and linguistic factors. Analysis of the pairwise F(ST) distances demonstrated close genetic similarity of Koreans to Northern Chinese, which in turn, were clearly different from Southern Chinese populations. Mongolians occupied an intermediate position between the ethnic groups of South Siberia and Central/East Asia.

Urinary ascites and anuria caused by bilateral fungal balls in a premature infant

A case is reported of anuria and urinary ascites secondary to bilateral ureteropelvic obstruction by fungal balls. Management consisted of bilateral nephrostomy drainage with local irrigation with amphotericin B, and systemic antifungal treatment without surgery. Aspiration by paracentesis was performed for the urinary ascites and continuous drainage through an 8 Fr pig tail catheter for the urinoma. The literature on renal fungus balls in neonates and infants is reviewed.

Circumcision practice patterns in South Korea: community based survey

OBJECTIVES

To assess the prevalence of circumcision in South Korean young men dwelling in the community, investigate attitudes and perspectives about circumcision, and how they perceive physician involvement in the decision process.

METHODS

Between May and November 2001, this cross sectional survey was performed. Of 27 202 men aged 20 years dwelling in the community of Choong-chung South Province, 2700 were randomly selected at a 10.0% sampling fraction after a sampling process by census district and a total of 1742 (64.5%) agreed to participate in the study. These subjects completed self administered questionnaires and we included 1674 men (a response rate 62.0%) in the study.

RESULTS

The overall proportion of circumcised was 1306 (78.0%) and an additional 192 (11.5%) wished to be circumcised later. Circumcision was carried out mostly during their elementary and middle school years. Of men circumcised, the decision whether to circumcise was most often made by their parents. Of the subjects, 75.0% believed that circumcision is necessary, while 2.9% believed it to be unnecessary. Among those who believed circumcision to be necessary, the most common reason was to improve penile hygiene (89.1%).

CONCLUSIONS

Our results indicate a positive attitude toward circumcision in South Korean men, linking it with hygienic practices. Circumcision in South Korea depends on the perpetuation of cultural beliefs that support it.

Psychological problems in young men with chronic prostatitis-like symptoms

OBJECTIVE

To take a different perspective in assessing young men with chronic prostatitis-like symptoms, this study was designed since few prospective studies are available to survey a population of young men.

MATERIAL AND METHODS

One hundred and fifty men aged 20 years dwelling in the community were randomly selected. Chronic prostatitis-like symptoms were measured by the National Institutes of Health-Chronic Prostatitis Symptom Index and the selfreported scores for pain and urinary symptoms were used to identify chronic prostatitis-like symptoms. The psychological methods used were the Beck Depression Inventory, the State-Trait Anxiety Inventory, and the Bem Sex Role Inventory. A total of 87 men (a response rate 58%) completed self-administered questionnaires.

RESULTS

As the scores for pain and urinary symptoms increased, those for depression increased (p < 0.001 and p = 0.01, respectively). However, the mean scores for state and trait anxiety were not different according to the scores for pain and urinary symptoms. The mean masculinity scores were not different according to the scores for pain but those were significantly different according to the scores of urinary symptoms (p = 0.042). The mean femininity scores were not different according to the scores of pain and urinary symptoms.

CONCLUSIONS

Our findings suggest that psychological factors, especially depression and weak masculine identity may be associated with an early stage of chronic prostatitis-like symptoms. Young men with chronic prostatitis-like symptoms also have psychological problems.

Factors influencing testicular volume in young men: results of a community-based survey

OBJECTIVE

To investigate the factors influencing testicular volume in young men in the community.

SUBJECTS AND METHODS

Between May and November 2001, 2700 men aged 20 years and dwelling in the community were randomly selected at a 10% sampling fraction after a sampling process by census district; 2080 men agreed to participate in the study. All volunteers underwent a standard evaluation, including a detailed medical history and physical examination. After excluding those with testicular diseases the study comprised 1792 men.

RESULTS

There were significant but weak correlations between testicular volumes and height, body weight and body mass index. In a multivariate model, high environmental temperature was associated with a decreased likelihood (odds ratio, OR, 0.42; 95% confidence interval, CI, 0.29-0.60; P < 0.001) of a paired testicular volume being below the 25th percentile of all participants. The likelihood of a low paired testicular volume varied by area, with a 1.6-fold greater risk in men dwelling in large rural areas than in those in major towns. Increasing height was associated with a decreased likelihood (OR 0.60; 95% CI 0.38-0.96; P = 0.032) and low body weight with an increased likelihood of a low paired testicular volume (OR 2.54; 95% CI 1.57-4.12; P < 0.001).

CONCLUSION

These results establish that demographic and environmental factors have an effect on testicular size and suggest that body size may be important in determining testicular size in late adolescents.

Influence of environmental factors on chronic prostatitis-like symptoms in young men: results of a community-based survey

OBJECTIVES

To investigate the influence of environmental factors on chronic prostatitis-like symptoms among young men in a community.

METHODS

Of 28,841 men aged 20 years dwelling in the community, a total of 16,321 men (response rate 56.6%) were included in this study. The National Institutes of Health Chronic Prostatitis Symptom Index was used to identify men with chronic prostatitis-like symptoms. The questionnaire also queried sociodemographic characteristics. The Korean Meteorological Administration provided information on the weather of the community. We determined the risk factors of chronic prostatitis-like symptoms among these environmental factors using univariate and multivariate analyses.

RESULTS

Six percent of the men were identified as having significant prostatitis-like symptoms (perineal and/or ejaculatory pain and a total pain score of 4 or greater). The univariate logistic regression analysis indicated that education level, average duration of sunlight, and average temperature were risk factors for chronic prostatitis-like symptoms. As these variables increased, the scores of chronic prostatitis-like symptoms decreased. In the multivariate model used, the likelihood of chronic prostatitis-like symptoms varied by the final educational level, with middle school and high school graduates having 1.8 and 1.4-fold higher odds, respectively, than men attending college. In the same model, the average duration of sunlight was also an independent risk factor of chronic prostatitis-like symptoms (odds ratio 0.85; 95% confidence interval 0.77 to 0.95; P = 0.003), but the average temperature lost statistical significance.

CONCLUSIONS

Our findings suggest that the community-based prevalence of chronic prostatitis-like symptoms may be high in young men. Higher education and a longer time in sunlight were associated with a decreased likelihood of chronic prostatitis-like symptoms.

Is there a role of radial rigidity in the evaluation of erectile dysfunction?

RigiScan has been the most widely utilized device for measuring erectile rigidity. However, the use of the RigiScan in the evaluation of erectile dysfunction has questionable because the RigiScan device does not directly determine axial rigidity. The aim of this study is to clarify that radial rigidity measured by RigiScan reflects the intracorporeal pressure and erectile capability efficiently. From January 1998 to May 1999, a total of 23 patients with erectile dysfunction were involved in the study. They were evaluated by RigiScan and duplex ultrasonography after intracorporeal injection of prostaglandin E1. We investigated the relationship between radial rigidity and the resistance index. The results of radial rigidity were also compared with that of the degree of erection. For the entire group, significant correlations were found between radial rigidity and the resistance index (r=0.680, P<0.001 for tip rigidity; r=0.703, P<0.001 for base rigidity). In addition, for 12 patients whose tip rigidity exceeded 60% and for 10 whose base rigidity exceeded 60%, the correlations between radial rigidity and the resistance index remained (r=0.659, P=0.020 for tip rigidity; r=0.759, P=0.011 for base rigidity). Based on the response determined by patients, radial rigidity represented the degree of erection efficiently. Our findings suggest that RigiScan is a useful diagnostic tool. Radial rigidity represents the intracorporeal pressure efficiently and has an acceptable role in the evaluation of erectile dysfunction.

Is there a role for magnetic resonance imaging in renal trauma?

BACKGROUND

Computed tomography (CT) has been the most informative imaging method in renal trauma. Despite the good sensitivity of magnetic resonance imaging (MRI) to the presence of hematoma, edema and ischemia, MRI has not been widely studied in patients with renal trauma. The present study was initiated to evaluate the role of MRI in patients with renal trauma.

METHODS

Between June 1998 and September 1999, CT and MRI were prospectively performed on 12 patients who suffered from renal trauma and the results reviewed.

RESULTS

The presence and size of perirenal hematoma could be detected by both CT and MRI. Magnetic resonance imaging could differentiate intrarenal hematoma from perirenal hematoma more accurately, and provided additional information about the hematoma as T1- and T2-weighted MRI were able to determine recent bleeding in the hematoma by regional differences in signal intensity. Magnetic resonance imaging clearly revealed renal fracture with non-viable fragment and detected focal renal laceration that was not detected on CT due to perirenal hematoma associated with renal infarction. However, although MRI had many advantages over CT, it had also major drawbacks, which were that it required longer imaging time and increased the cost.

CONCLUSIONS

Magnetic resonance imaging may be useful in renal trauma. However, it is suggested that MRI should be limited to carefully selected patients, such as those with severe renal injury or equivocal findings on CT.

The prevalence of chronic prostatitis-like symptoms in young men: a community-based survey

We surveyed the prevalence of chronic prostatitis-like symptoms in young men using the National Institutes of Health (NIH) Chronic Prostatitis Symptom Index (CPSI) and determined the clinical validity of the NIH-CPSI among men in the community. Of 29,017 men aged 20 years dwelling in the community, 8,705 men were randomly selected at a 30.0% sampling fraction and a total of 6,940 men (a response rate 79.7%) completed a self-administered questionnaire. Six percent reported having pain or discomfort in more than one area . About 5% did not feel that the bladder emptied fully after urinating more than 1 time in 5 and 10.5% had to urinate again within 2 h more than 1 time in 5. As the scores for pain or discomfort increased, those for urinary symptoms and impact on quality of life increased (P < 0.001; Armitage test). As the scores for urinary symptoms increased, those for pain or discomfort and impact on quality of life also increased (P < 0.001; Armitage test). The community-based prevalence of chronic prostatitis-like symptoms were found to be high in young men as well as in older men. Our findings indicate that men with pain or urinary symptoms experience a negative impact on their quality of life and the NIH-CPSI provides a valid measure for the general population.