Prostate cancer detection rate according to lesion visibility using ultrasound and MRI.

AIM: To evaluate the difference in prostate cancer detection rates according to lesion visibility using transrectal ultrasound (TRUS) and magnetic resonance imaging (MRI) before biopsy. MATERIALS AND METHODS: Patients who underwent TRUS-guided prostate biopsy in 2016 and 2017 (n=1,022) were divided into three groups: (1) patients who did not undergo a prebiopsy MRI (group 1, n=622); (2) patients without visible lesions on the prebiopsy MRI (group 2, n=77); and (3) patients with visible lesions on the prebiopsy MRI (group 3, n=323). Biopsy results were compared using chi-square tests or independent t-tests between patients with and without TRUS-visible lesions in each group. A logistic regression test was used to determine the variables independently associated with the detection of clinically significant cancer. RESULTS: Focal lesions were visible on TRUS in 710 patients. Clinically significant cancers were detected in 39.4% and 13.1% of patients with and without TRUS-visible lesions, respectively (p<0.001). The cancer detection rate was significantly higher in patients with TRUS-visible lesions in groups 1 and 3 (p<0.001). Within group 1, the Gleason scores, number of positive cores, and the cancer involvement ratios were significantly greater in patients with TRUS-visible lesions than in patients without TRUS-visible lesions. MRI- and TRUS visibility were positively associated with the detection of clinically significant prostate cancer (p=0.002 and p<0.001, respectively). CONCLUSION: TRUS- and MRI-visible focal lesions in the prostate were significantly associated with the detection of clinically significant cancer.

Prebiopsy biparametric MRI: differences of PI-RADS version 2 in patients with different PSA levels.

AIM: To validate the diagnostic accuracy of Prostate Imaging-Reporting and Data System (PI-RADS) version 2 in detecting clinically significant prostate cancer (csPCa, Gleason score ≥7) on prebiopsy biparametric MRI (bpMRI) in patients with different prostate-specific antigen (PSA) levels. MATERIALS AND METHODS: This retrospective study included 184 patients who underwent prebiopsy bpMRI followed by transrectal ultrasonography-guided biopsy between June 2015 and February 2017. Reader 1 performed a combination of systematic and targeted biopsy with cognitive fusion after reviewing bpMRI and reader 2 reviewed the bpMRIs retrospectively. PI-RADS categories 4 and 5 were considered positive, and the results of the biopsy were considered the reference standard. Diagnostic performance of PI-RADS of bpMRI was evaluated in two PSA groups with a PSA cut-off level of 10 ng/ml and compared to PSA and the PSA density using receiver operating characteristics (ROC) curve analysis. RESULTS: csPCa was diagnosed in 24 of 123 patients (19.5%) and 26 of 61 patients (42.6%) in the low and high PSA groups, respectively. A PI-RADS v2 category by either readers 1 or 2 had a significantly better performance to detect csPCa than PSA in both PSA groups. In the high PSA group, only one csPCa was missed by reader 2, but none by reader 1. In the low PSA group, readers 1 and 2 were unable to detect seven and five of the 24 csPCas, respectively. CONCLUSION: Prebiopsy bpMRI has good performance for detecting csPCa in the high PSA group but may miss small-volume csPCa in the low PSA group.

Functional splicing assay of DSPP mutations in hereditary dentin defects.

OBJECTIVE: Dentin sialophosphoprotein (DSPP) gene mutations have been identified in isolated hereditary dentin defects; however, the genotype-phenotype correlations are poorly understood. We performed in vitro splicing assays to test the hypothesis that DSPP mutations in splice junctions as well as proposed missense/nonsense mutations experimentally result in aberrant pre-mRNA splicing. MATERIALS AND METHODS: The genomic fragment of the human DSPP gene was cloned into the pSPL3 splicing vector, and previously reported as well as informative de novo mutations were then introduced by PCR mutagenesis. The COS-7 cells were transfected with each plasmid vector, and total RNA was isolated. RT-PCR result was analyzed, and the band intensity of the product was calibrated using ImageJ. RESULTS: The predictions by others of exon 3 skipping in specific DSPP mutations have been validated and a cryptic splicing donor site has been identified. However, the degree of mutational effect on pre-mRNA splicing varied considerably depending on the changed nucleotide. CONCLUSIONS: The predictions of exon 3 skipping in specific DSPP mutations have been validated, and a cryptic splicing donor site has been identified. Our data may provide insight into the contribution of DSPP mutations in the pathogenesis and genotype-phenotype correlations of hereditary dentin defects.

Dynamic contrast-enhanced MR imaging of the rectum: Correlations between single-section and whole-tumor histogram analyses.

PURPOSE: To evaluate the interobserver and intermethod correlations of histogram metrics of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters acquired by multiple readers using the single-section and whole-tumor volume methods. MATERIALS AND METHODS: Four DCE parameters (Ktrans, Kep, Ve , Vp) were evaluated in 45 patients (31 men and 14 women; mean age, 61±11 years [range, 29-83 years]) with locally advanced rectal cancer using pre-chemoradiotherapy (CRT) MRI. Ten histogram metrics were extracted using two methods of lesion selection performed by three radiologists: the whole-tumor volume method for the whole tumor on axial section-by-section images and the single-section method for the entire area of the tumor on one axial image. The interobserver and intermethod correlations were evaluated using the intraclass correlation coefficients (ICCs). RESULTS: The ICCs showed excellent interobserver and intermethod correlations in most of histogram metrics of the DCE parameters. The ICCs among the three readers were > 0.7 (P<0.001) for all histogram metrics, except for the minimum and maximum. The intermethod correlations for most of the histogram metrics were excellent for each radiologist, regardless of the differences in the radiologists' experience. CONCLUSION: The interobserver and intermethod correlations for most of the histogram metrics of the DCE parameters are excellent in rectal cancer. Therefore, the single-section method may be a potential alternative to the whole-tumor volume method using pre-CRT MRI, despite the fact that the high agreement between the two methods cannot be extrapolated to post-CRT MRI.

Identification of stathmin 1 expression induced by Epstein-Barr virus in human B lymphocytes.

INTRODUCTION: The Epstein-Barr virus transforms resting B cells into proliferating lymphoblastoid cells, the origin of cell lines. METHOD AND RESULTS: Our cDNA microarray analyses led to the identification of 232 up-regulated and 112 down-regulated genes with more than a 3-fold difference in lymphoblastoid cell lines compared to resting B cells. The functional classification of these genes exhibited the distinct expression signature for cell proliferation, cell cycle and an immune response. Among them, we verified the differential expression of several oncogenes such as stathmin 1 (STMN1), RAB27A, RAB9A, BACH1 and BACH2 using quantitative real-time reverse transcriptase-polymerase chain reactions or Western blot analysis. Expression of STMN1 (which is involved in regulation of the microtubule filament system, cell growth and S-phase of cell cycle) was increased in lymphoblastoid cell line as well as in 7-day post-Epstein-Barr virus infection B cells, compared to resting B cells. CONCLUSION: Thus, this study suggests that Epstein-Barr virus infection induces STMN1 expression, which play a role in cell cycle progression and proliferation in the human B lymphocyte.

Activation of human tumor-infiltrating lymphocytes by monoclonal antibodies directed to the CD3 complex.

We have used high concentrations of recombinant-methionyl human interleukin 2 (rIL-2) for the initial growth and expansion of human tumor-infiltrating lymphocytes (TIL). Early in the life of the TIL bulk culture, cytotoxicity was non-major histocompatibility complex restricted. Under these culture conditions antitumor cytotoxicity was observed to decline with increasing age of the bulk culture. In addition, TIL became refractory to rIL-2-induced expansion. We have used solid-phase anti-CD3 antibodies for TIL activation followed by culture in reduced concentrations of rIL-2 to reactivate TIL previously grown in high concentrations of rIL-2. TIL refractory to rIL-2 in terms of growth and antitumor cytotoxicity proved sensitive to anti-CD3 activation. The use of solid-phase anti-CD3 was also more effective than high concentrations of rIL-2 in the expansion of TIL when used at the start of culture. Finally, TIL could be induced to secrete IL-2 following solid-phase activation with anti-CD3. These data suggest that human TIL are susceptible to activation by signals directed at the CD3 complex of the TIL cell surface.

Current status of medical radiation exposure in Korea - recent efforts to develop a radiation exposure control system focussed on justification and optimisation.

Radiation exposure from diagnostic medical imaging has increased in Korea. Radiological societies play a key role in radiation safety issues in Korea, including guidelines, accreditation, advocacy, scientific activity, and education. Any medical radiation exposure must be justified, and examinations using ionising radiation must be optimised. Education of referring physicians and radiologists is also important for justification. Medical physicists and radiographers have an important role to play in quality management and optimisation. Regulations are essential to control medical radiation exposure. Therefore, national organisations have made a significant effort to regulate and monitor medical radiation exposure using guidelines, accreditation, and even the law. Medical radiation exposure must be controlled, and this could be achieved by continuous interest from health professionals and organisations.

A new regimen of interleukin 2 and lymphokine-activated killer cells. Efficacy without significant toxicity.

Adoptive immunotherapy with high-dose interleukin 2 and lymphokine-activated killer (LAK) cells has proved to be successful in the treatment of some patients with metastatic cancer, but not without a significant degree of associated toxic effects. The primary goal of this study was to substantially reduce the toxicity of this complex and expensive treatment, while maintaining or improving efficacy. To this end, 29 patients were treated with LAK cells in conjunction with a low-dose regimen of interleukin 2 and a prolonged period of administration following LAK cell infusion. This protocol resulted in a considerable reduction in toxicity, as compared with that described in previous studies, without compromising the efficacy. This study offers further confirmation that adoptive immunotherapy of metastatic cancer can be clinically beneficial to patients for whom no other effective therapy is presently available.

Tolerance to rat liver allografts: IV. Acceptance depends on the quantity of donor tissue and on donor leukocytes.

Liver allografts in some rat strains are often spontaneously accepted across a complete major histocompatibility barrier without the requirement for immunosuppression while other nonliver allografts are rejected. In previous studies, we have shown that spontaneous acceptance is dependent on liver passenger leukocytes. Depletion of passenger leukocytes by donor irradiation allows rejection, with DA recipients of irradiated PVG livers having a median survival time (MST) of 16 days. Here we show that, in this model, spontaneous acceptance is reconstituted by intravenous injection of donor leukocytes. Intravenous injection of 3-5x10(7) PVG liver leukocytes significantly prolonged DA survival time (MST=96 days, P=0.026), as did 5x10(7) spleen leukocytes (MST>100 days, P=0.002). Deletion of T cells from the reconstituting inoculum reduced survival time (MST=78 days, P=0.039), whereas deletion of B cells or monocytes/macrophages had no effect on survival time. In contrast, PVG hearts are regularly rejected by DA recipients, and PVG liver or spleen leukocytes, even at doses of greater than 3x10(8) cells/recipient, were unable to induce heart acceptance. To investigate the possibility that acceptance of the irradiated liver but not the heart might be due to the large mass of the liver, two kidneys and two hearts of PVG origin were transplanted to each DA recipient together with 1.5x10(8) PVG leukocytes. These organs survived for greater than 200 days, thereby showing that a large mass of donor tissue, in association with donor leukocytes, leads to acceptance of organs that are rejected if transplanted singly. It appears likely that spontaneous liver transplant tolerance is a high-dose or activation-associated immune phenomenon.

Cloning and analysis of the DNA polymerase-encoding gene from Thermus filiformis.

The gene encoding Thermus filiformis (Tfi) DNA polymerase was cloned and its nucleotide sequence was determined. The primary structure of Tfi DNA polymerase was deduced from its nucleotide sequence. Tfi DNA polymerase is comprised of 833 amino acid residues and its molecular mass was determined to be 93,890 Da. The deduced amino acid sequence of Tfi DNA polymerase showed a high sequence homology to E. coli DNA polymerase I-like DNA polymerases: 78.5% homology to Taq DNA polymerase, 78.4% to Tca DNA polymerase, and 41.8% to E. coli DNA polymerase I. An extremely high sequence identity was observed in the region containing polymerase activity. The G + C content of the coding region for the Tfi DNA polymerase gene was 68.5%, which was higher than that of the chromosomal DNA (65%). The G + C contents in the first, second, and third positions of the codons used were 71.8%, 40.9%, and 92.7% respectively. Codon usage in Tfi DNA polymerase was heavily biased towards the use of G + C in the third position. Rare codons with U or A as the third base were sometimes used to avoid using GA(A/T) TC and TCGA sequences, as they are recognition sites for the restriction endonucleases TfiI and TaqI.

MR findings in ovarian granulocytic sarcoma.

Granulocytic sarcoma (chloroma) is a mass of malignant myeloid precursor cells in an extramedullary location. The female genital tract, including the ovary, may be the first site for clinical manifestation of granulocytic sarcoma. The MR findings are reported in a case of ovarian granulocytic sarcoma which preceded acute myelogenous leukaemia. Granulocytic sarcoma shows a mixed cystic and solid adnexal mass with intermediate signal intensity on T1 weighted images and hypointensity on T2 weighted images.

Benign solitary fibrous tumour of the pre-sacral space: MRI findings.

Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space.

The findings of ruptured hepatocellular carcinoma on helical CT.

To evaluate the helical CT findings of ruptured hepatocellular carcinoma (HCC), 12 patients with ruptured HCC were reviewed with regard to the tumour's location, size and contour protrusion, the appearance of the mass, the enhancement pattern, multiplicity and secondary changes. All ruptured tumours were located at the periphery of the liver and had a protruding contour. The maximum diameter of tumours ranged from 2 cm to 16 cm. Discontinuity of the hepatic surface was seen in 11 cases. In eight cases, CT images during the arterial phase showed a non-enhancing low attenuating lesion with focal discontinuity and peripheral rim enhancement. Seven cases showed separation of tumour content from the peripheral enhancing rim and intraperitoneal rupture of tumour content into the perihepatic space. Because of the similar appearance to an enucleated orbital globe with remaining sclera, this was termed the "enucleation sign". As well as ruptured masses, 10 cases with non-ruptured masses also showed a non-enhancing low attenuating pattern. Seven cases showed a haematoma with high attenuation around the ruptured mass. The peripheral location, protruding contour, discontinuity of the hepatic surface and surrounding haematoma are helpful signs in the diagnosis of ruptured HCC. The "enucleation sign" may be a characteristic finding in ruptured HCC.

Silo formation without suturing in gastroschisis: use of Steridrape for delayed repair.

Although primary repair is preferred for gastroschisis, this cannot be performed in many patients because of the visceroabdominal disproportion or other accompanying conditions. Several prosthetic materials are used for a silo or patch. When prosthetics are used, staged operations are necessary and infection is an inherent problem. However, these problems can be avoided by using Steridrape for a silo without suturing. The authors used the Steridrape to create a covering for two patients. The eviscerated bowel was irrigated and the abdominal wall was cleansed. A sheet of Steridrape was attached onto the abdominal wall and the herniated viscera was wrapped with it. A second sheet was applied over the first one. Antibiotics were administered and parenteral nutrition was started. The Steridrape covering was changed twice a week. In 1 week the edema subsided remarkably and in 2 weeks the bowel had an almost normal appearance except for hyperemic serosa. Primary repair was performed on the 19th hospital day in patient 1, the 14th day in patient 2. Oral feeding was started 7 days after repair in patient 1, and 22 days after repair in patient 2. Patient 2 developed aspiration pneumonia during transport. Discharge was on the 18th day after surgery in patient 1 and the 50th day in patient 2. The patients are now 18 months and 14 months old, respectively, and are doing well. Steridrape application in gastroschisis is economical, easy to perform, and is a better method to use when transporting the patient. It also facilitates drainage of purulent exudate, and allows the bowel to be inspected easily. This method has proved useful in treating two patients with gastroschisis.

Lipoblastoma.

BACKGROUND/PURPOSE: Lipoblastoma is a rare benign mesenchymal tumor of embryonal fat that occurs almost exclusively in infants and children. This study was done to determine the clinical and pathologic characteristics of lipoblastoma. METHODS: Nine cases of pathologically proven lipoblastoma from 1979 to 1997 were reviewed. There were 6 boys and 3 girls ranging in age from 3 months to 29 months. RESULTS: A soft tissue mass was the chief complaint in 7 patients, abdominal distension in 1 patient with a retroperitoneal mass, and defecation difficulty in 1 patient with a perirectal mass. In 4 patients, tumors occurred on the back. Other tumor location includes the neck, scrotum, retroperitoneum, perirectal area, and buttock in 1 patient each. Lesions measured 2.3 to 19.5 cm. Complete excision was done in 8 patients. One perirectal tumor was removed by both the posterior sagittal approach and the intraabdominal approach but incompletely resected. Two tumors located on the back recurred with intraspinal extension 12 months and 18 months after resection. Second resection and second resection with laminectomy were done. Leg pain and urinary incontinence developed in 1 patient but improved on conservative treatment. CONCLUSIONS: Lipoblastoma is a benign neoplasm but can frequently recur (25%) in spite of complete excision. Lipoblastomas occurring on the back had a high recurrence rate (50%) and associated with intraspinal extension. J Pediatr Surg 36:905-907.

Currarino triad: anorectal malformation, sacral bony abnormality, and presacral mass--a review of 11 cases.

Currarino et al, in 1981, described an association of a congenital anorectal stenosis, or another type of low anorectal malformation, an anterior sacral defect, and presacral mass. Eleven patients with this anomaly were treated at the Department of Pediatric Surgery, Seoul National University Children's Hospital from 1984 to 1995. Among these patients, low-type imperforate anus (IA) was seen in three cases and anorectal stenosis was present in eight cases. Presacral masses included seven teratomas, two meningoceles, one dermoid cyst, and one enteric cyst with dermoid cyst. All had a deformed sacrum. Among the eight with anorectal stenoses, posterior sagittal anorectoplasty (PSARP) with diverting colostomy was performed in seven cases, and repeated rectal dilatation was performed in one case. Among the three low-type IA, anoplasty was performed in two cases and PSARP was performed in one case. Although PSARP is a safe and satisfactory method facilitating the excision of the presacral mass, in meningoceles the repair should be performed before correction of anorectal malformation because of the risk of meningitis that can occur when surgeries are done simultaneously. In two cases, untethering of a tethered spinal cord was performed. All patients are continent. Because the incidence of Currarino triad is high when there is an anorectal stenosis (38% in the present series), the Currarino triad should be suspected in anorectal stenosis. Magnetic resonance imaging is a preferred diagnostic method because the incidence of association of tethered cord in this triad is high (18% in the present series).

Recombinant human growth hormone decreases lung and liver tissue lipid peroxidation and increases antioxidant activity after thermal injury in rats.

The combination of increased oxidant with decreased endogenous polypeptide and protein antioxidant activity corresponds to a decrease in cellular energetics and cell membrane lipid peroxidation. Providing large doses of growth hormone has been shown to preserve cell mass and organ function after burn injury. The role of growth hormone in oxidant injury has not been defined. We determined whether growth hormone altered the degree of lung and liver lipid peroxidation and the activity of glutathione and catalase in lung and liver tissue after burn injury. Four groups of 40 rats each were studied for 48 hours, with 1 group receiving a 20% full-thickness burn, 1 group treated with growth hormone after 20% full-thickness burn injury, a control group, and a growth hormone alone-treated group. We found increased lipid peroxidation, measured as malondialdehyde, in lung and liver tissue, and a decrease in glutathione and catalase activities during the 48-hour post-burn period. The addition of growth hormone prevented the lipid peroxidation and significantly increased tissue glutathione and catalase activities with respect to control values. Growth hormone alone also increased endogenous antioxidant levels. We conclude that growth hormone given after burn injury decreases oxidant stress by producing a significant increase in the endogenous antioxidants glutathione and catalase.

Corneal endothelial response to polymethylmethacrylate versus hydrogel lenses after phacoemulsification.

We performed a study to evaluate the corneal endothelial cell response in 26 patients who received a polymethylmethacrylate (PMMA) intraocular lens and 26 patients who received a soft, nonfolded poly-hydroxy-ethylmethacrylate (poly-HEMA) intraocular lens after posterior chamber phacoemulsification. Specular microscopy and pachymetry were done before surgery and a mean of 8 or more weeks after surgery. The mean percent cell loss was 8.2% in the PMMA group and 10.7% in the poly-HEMA group. There was no significant difference in the pachymetry values before or after surgery between the two groups; however, in the poly-HEMA group the postoperative value was significantly higher than the preoperative value (p = 0.027). The results suggest that the amount of perioperative corneal endothelial cell loss with poly-HEMA lenses is similar to that with PMMA lenses. Further study is needed to fully evaluate the long-term corneal effects of poly-HEMA lenses.