Correlation between the molecular subtype of breast cancer and the in vitro adenosine triphosphate-based chemosensitivity assay / 대한외과학회지

PURPOSE: The empirical use of a chemotherapy regimen shows different results in individual breast cancer patient treatment. Recent studies showed the effectiveness of the adenosine triphosphate-based chemotherapy response assay (ATP-CRA). However, little is known about the correlation between chemosensitivity and breast cancer molecular subtypes. Therefore, we investigated whether the result of ATP-CRA is associated with a molecular subtype of breast cancer. METHODS: Two hundred eighty-seven patients diagnosed with breast cancer and receiving ATP-CRA at Mokdong Hospital, Ewha Womans University between September 2007 and December 2010 were enrolled in this study. Hormone receptor status, HER2/neu expression, and results of chemosensitivity tests of the patients was analyzed. RESULTS: In all of four subtypes, the combination of two agents showed significant higher mean cell death rate than a single agent. Within the breast cancer cell lines in this study, the range of chemosensitivity response was very wide and varied for each patient. For this reason, the molecular subtype of breast cancer is inconclusive in choosing an effective chemotherapeutic agent and in vitro chemosensitivity test, prior to therapy, could be a useful method for planning chemotherapy for each patient. CONCLUSION: Chemosensitivity response to anticancer agents was found to vary depending on the individual breast cancer patients. The molecular subtype of breast cancer is inconclusive to choose the effective chemotherapeutic agent and the in vitro chemosensitivity test, prior to therapy, could be more useful for planning chemotherapy for each patient.

An Analysis of Factors Associated with Increased Perineal Descent in Women

PURPOSE: Treatment of descending perineal syndrome is focused on personal etiology and on improving symptoms. However, the etiology of increased perineal descent (PD) is unclear. Therefore, the aim of the present study was to evaluate factors associated with increased resting and dynamic PD in women. METHODS: From January 2004 to August 2010, defecographic findings in 201 female patients were reviewed retrospectively. Patient's age, surgical history, manometric results and defecographic findings were compared with resting and dynamic PD. RESULTS: Age (P < 0.01), number of vaginal deliveries (P < 0.01) and resting anorectal angle (P < 0.01) were correlated with increased resting PD. Also, findings of rectoceles (P < 0.05) and intussusceptions (P < 0.05) were significantly correlated with increased resting PD. On the other hand, increased dynamic PD was correlated with age (P < 0.05), resting anal pressure (P < 0.01) and sigmoidoceles (P < 0.05). No significant correlation existed between non-relaxing puborectalis, history of pelvic surgery and increased PD. Also, no significant differences in PD according to the symptoms were observed. CONCLUSION: Increased number of vaginal deliveries and increased resting rectoanal angle are associated with increased resting PD whereas increased resting anal pressure is correlated with increased dynamic PD. Older age correlates with both resting and dynamic PD. Defecographic findings, such as rectoceles and intussusceptions, are associated with resting PD, and sigmoidoceles correlated with dynamic PD. These results can serve as foundational research for understanding the pathophysiology and causes of increasing PD in women better and for finding a fundamental method of treatment.

Enhancement of the Deformable Image Registration Accuracy Using Image Modification of MV CBCT / 의학물리

To perform the Adaptive Radiation Therapy (ART), a high degree of deformable registration accuracy is essential. The purpose of this study is to identify whether the change of MV CBCT intensity can improve registration accuracy using predefined modification level and filtering process. To obtain modification level, the cheese phantom images was acquired from both kilovoltage CT (kappaV CT), megavoltage cone-beam CT (MV CBCT). From the cheese phantom images, the modification level of MV CBCT was defined from the relationship between Hounsfield Units (HUs) of kappaV CT and MV CBCT images. 'Gaussian smoothing filter' was added to reduce the noise of the MV CBCT images. The intensity of MV CBCT image was changed to the intensity of the kappaV CT image to make the two images have the same intensity range as if they were obtained from the same modality. The demon deformable registration which was efficient and easy to perform the deformable registration was applied. The deformable lung phantom which was intentionally created in the laboratory to imitate the changes of the breathing period was acquired from kappaV CT and MV CBCT. And then the deformable lung phantom images were applied to the proposed method. As a result of deformable image registration, the similarity of the correlation coefficient was used for a quantitative evaluation of the result was increased by 6.07% in the cheese phantom, and 18% in the deformable lung phantom. For the additional evaluation of the registration of the deformable lung phantom, the centric coordinates of the mark which was inserted into the inner part of the phantom were measured to calculate the vector difference. The vector differences from the result were 2.23, 1.39 mm with/without modification of intensity of MV CBCT images, respectively. In summary, our method has quantitatively improved the accuracy of deformable registration and could be a useful solution to improve the image registration accuracy. A further study was also suggested in this paper.

Evaluation of Scatter Reduction Effect of the Aft-Multiple-Slit (AMS) System Using MC Simulation / 대한방사선종양학회지

PURPOSE: We designed the aft-multiple-slit (AMS) system to reduce scatter in cone-beam computed tomography (CBCT). As a preliminary study, we performed a Monte Carlo N-Particle Transport Code (MCNP) simulation to verify the effectiveness of this system. MATERIALS AND METHODS: The MCNPX code was used to build the AMS geometry. An AMS is an equi-angled arc to consider beam divergence. The scatter-reduced projection images were compared with the primary images only and the primary plus scatter radiation images with and without AMS to evaluate the effectiveness of scatter reduction. To obtain the full 2 dimensional (2D) projection image, the whole AMS system was moved to obtain closed septa of the AMS after the first image acquisition. RESULTS: The primary radiation with and without AMS is identical to all the slit widths, but the profiles of the primary plus scattered radiation varied according to the slit widths in the 2D projection image. The average scatter reduction factors were 29%, 15%, 9%, and 8% when the slit widths were 5 mm, 10 mm, 15 mm, and 20 mm, respectively. CONCLUSION: We have evaluated the scatter reduction effect of the AMS in CBCT imaging using the Monte Carlo (MC) simulations. A preliminary study based on the MCNP simulations showed a mount of scatter reduction with the proposed system.

Analysis of the Management of Children with Abdominal Solid Organ Injuries

PURPOSE: In pediatric solid organ injury, non-operative management is considered as a standard treatment when the patient is hemodynamically stable. However, treatment according to the injured organ and the depth of injury is controversial. The purpose of this study is to evaluate treatment results in the management of abdominal solid organ injuries in children. METHODS: This analysis was performed retrospectively with 57 consecutive children under 15 year of age who were diagnosed with abdominal solid organ injuries at Ewha Womans University Mokdong Hospital from January, 1999 to June, 2007. RESULTS: The major cause of pediatric solid organ injury was traffic accidents (59.6%) and the most frequently injured organ was the liver (66.7%). 54 patients (94.7%) were treated non-operatively and the success rate was 100%. There was no difference in type of management and success rate according to the depth of injury or the injured organs. The average ICU stay was 4.3 days, and the average hospital stay was 13.6 days and that was extended depending on the depth of injury. And according to the cause of injury, cases by traffic accident stayed significantly longer than cases by other causes. CONCLUSION: High grade of injury is not contraindication of nonoperative management in pediatric solid organ injury. Hemodynamic instability is the only absolute indication of operation. Therefore, if the patient is stable, non-operative management with intensive observation is the choice of treatment.

Verification of Skin Dose in Tomotherapy Using the Developed Phantom for Image Based Radiation Treatment System / 의학물리

Radiation treatment for skin cancer has recently increased in tomotherapy. It was reported that required dose could be delivered with homogeneous dose distribution to the target without field matching using electron and photon beam. Therapeutic beam of tomotherapy, however, has several different physical characteristic and irradiation of helical beam is involved in the mechanically dynamic factors. Thus verification of skin dose is requisite using independent tools with additional verification method. Modified phantom for dose measurement was developed and skin dose verification was performed using inserted thermoluminescent dosimeters (TLDs) and GafChromic EBT films. As the homogeneous dose was delivered to the region including surface and 6 mm depth, measured dose using films showed about average 2% lower dose than calculated one in treatment planning system. Region indicating about 14% higher and lower absorbed dose was verified on measured dose distribution. Uniformity of dose distribution on films decreased as compared with that of calculated results. Dose variation affected by inhomogeneous material, Teflon, little showed. In regard to the measured dose and its distribution in tomotherapy, verification of skin dose through measurement is required before the radiation treatment for the target located at the curved surface or superficial depth.

Change of the Clinical Aspects and Management of Childhood Intussusception

PURPOSE & METHODS: Nonoperative reduction of childhood intussusception is the treatment of choice. However, few techniques of nonoperative reduction are available. When used, nonoperative reduction can be successfully completed by a radiologist. In this study, we analyzed 637 cases of childhood intussusception diagnosed and treated by ultrasound-guided saline enema reduction (UGSER) over nine years at Ewha Womans University Mokdong Hospital. We compared the results of 76 cases surgically treated after UGSER (US group) with 84 cases surgically treated after barium enema reduction in 1980s (BE group). RESULTS: The success rate of the saline reduction was 88.1%. The risk factors associated with surgery were the patient's age, symptom duration and the type of intussusception. The rate of bowel resection was 32.9%. Patients less than six months old and a pathologic lead point (PLP) on the US were risk factors for bowel resection. There were no significant differences in age, gender and the number of PLPs between the US and BE groups. The number of patients with a spontaneous reduction was greater in the BE group and bowel perforation occurred only in the US group. The bowel resection rate was significantly higher in the US group. However, the median hospital stay was significantly shorter in the US group. CONCLUSION: UGSER is reliable and safe in childhood intussusecption. Moreover, it has a high success rate and is easy to perform. The surgeon, without the need for a radiologist, performs this procedure from diagnosis to treatment. In addition, it might help avoid invasive surgery.

Cone-beam Reconstruction using Limited EPID Projections for Seeds Localization / 의학물리

In this study, we describe the preliminary application for the delineation of a metal object using cone-beam reconstruction (CBR) based on limited electronic portal imaging device (EPID) projections. A typical Feldkamp, Davis and Kress (FDK) reconstruction algorithm accompanying the edge preserving smoothing filter was used as only a few projections are acquired for reconstruction. In a correlation study of the projection numbers, we found that the size of the seeds and their location depicted by these CBR images were almost identical. Limited views were used for CBR, and our method is inexpensive and competitive for use in clinical applications.

Development of QA Phantom Prototype for Imaged Based Radiation Treatment System / 의학물리

In this study, we developed the protopype of QA phantom for image QA including an additional component for image based radiation treatment system. The new phantom considered two main parts: Image quality and fusion accuracy. Image quality part included for daily CT number linearity and spatial resolution, and fusion accuracy part designed to simulate a simple translation-rotation setting. The CT scans of the phantom obtained from conventional CT, MVCT of Tomotherapy unit, and both image sets were satisfied the recommendation of spatial resolution. This phantom was simple and efficient for daily imaging QA, and it is important to provide a new concept of verification of image registration.