Purpose: Prostate cancer is the most common male malignancy and the second leading cause of male ... more Purpose: Prostate cancer is the most common male malignancy and the second leading cause of male cancer death; therefore, there is urgent necessity for noninvasive assays for early detection of prostate cancer. Obtaining prostate tumor samples surgically is problematic because the malignancy is heterogeneous and multifocal and early-stage tumors are nonpalpable. In contrast, exfoliated cells represent the cancer status of the entire gland better due to the general tendency of cancer cells to exfoliate into biological fluids. The purpose of this study was to clarify whether quantitative analysis of telomerase activity in exfoliated cells in urine could serve as a reliable molecular marker of prostate malignancy. Experimental Design: We analyzed prospectively post-prostatic examination–exfoliated cells from the urine of 56 patients undergoing routine prostate screening. Epithelial cells were isolated and enriched by immunomagnetic separation. Telomerase activity was analyzed by quanti...
Entry into the retroperitoneal space during Minimally Invasive Transforaminal Lumbar Interbody Fu... more Entry into the retroperitoneal space during Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) presents a rare possibility of iatrogenic ureteral injury. Rare complications of ureteral injury after previous open posterior spinal surgery have been reported however there is a paucity of reports after a minimally invasive technique. We now describe a case of ureteral injury after MI-TLIF.
Recent data indicate a decline in the urological education of third and fourth year medical stude... more Recent data indicate a decline in the urological education of third and fourth year medical students. To determine if this decline has an impact on the treatment of patients we performed a survey to evaluate the general level of knowledge, attitudes and practices with regard to common urological issues seen in a general medical practice among medical students and faculty involved in primary care at an academic institution. Materials and Methods: A confidential questionnaire was distributed to attendings, residents and fellows, and the clinical medical students at our academic institution to ascertain how they evaluate and treat patients with common urological complaints. All responses were entered into SPSS® statistical software. Results: A total of 300 surveys were distributed, 150 of which were returned with complete information for data analysis. Knowledge with regard to various conditions including hematuria, recognition of an age specific abnormality in serum prostate specific antigen and overactive bladder was low for all groups. Furthermore, respondents demonstrated a low likelihood of requesting formal urological evaluation for these conditions. Exposure to a urology elective in medical school had a positive impact on some areas of urological evaluation. Conclusions: General urological knowledge with regard to the primary care setting is insufficient. The potential for impact on patient care is enormous. These data highlight the need for a definitive urological curriculum in medical school as well as continued education at the resident and faculty level with regard to evaluation, management and recognition of when to request formal urological evaluation in the primary care setting.
Purpose: The etiology of voiding dysfunction was determined in men after a cerebrovascular accide... more Purpose: The etiology of voiding dysfunction was determined in men after a cerebrovascular accident who were at risk for obstructive uropathy to evaluate whether the cause of voiding dysfunction could be predicted by the type (obstructive or irritative) or onset of symptoms. Materials and Methods: We evaluated 38 men with complaints of voiding dysfunction following a cerebrovascular accident. All patients were of the age when bladder outlet obstruction secondary to benign prostatic hyperplasia would otherwise be prevalent. After a comprehensive history and physical examination, all patients underwent multichannel urodynamic studies at a medium fill rate (20 to 50 ml. per minute). Findings were classified by the Abrams-Griffiths nomogram as obstruction, no obstruction or equivocal. Results: Mean patient age was 70 years (range 54 to 87). Patients were grouped according to the presenting voiding complaints (purely irritative in 42%, purely obstructive in 34% or mixed in 24%). In 34 patients (89%) the onset of symptoms paralleled the occurrence of the cerebrovascular accident. Detrusor hyperreflexia was noted in 82% of the patients. There was no statistically significant difference in the occurrence of detrusor hyperreflexia among the 3 symptom groups (Fisher's exact test). Pressure-flow analysis clearly showed obstruction in 24 patients (63%), no obstruction in 9 (24%) and equivocal results in 5 (13%) according to the nomogram. There was no statistically significant difference in the incidence of obstruction among the 3 symptom groups (Fisher's exact test). Conclusions: Presenting symptoms did not predict the urodynamic findings of bladder outlet obstruction or detrusor hyperreflexia. The significant incidence of onset of symptoms aRer stroke suggests that the cerebrovascular accident induced voiding dysfunction in the face of preexisting bladder outlet obstruction may exacerbate the symptoms of the latter condition or vice versa.
Percutaneous upper pole access may be obtained via the supracostal or subcostal approach. The mor... more Percutaneous upper pole access may be obtained via the supracostal or subcostal approach. The more cranial the location of the percutaneous nephrostomy tract, the greater the risk of incurring intrathoracic complications. We describe a technique for safely accessing the upper pole calix via a subcostal approach, even when the stone is located well above the 12th rib. In our patient the stone was located between the 11th and 12th ribs, and the upper pole extended to above the 10th rib. A 78-year-old man with multiple medical problems had a symptomatic upper right pole stone located between 11th and 12th ribs. Due to its size (3 x 2.2 cm), neither a ureteroscopic nor shockwave approach was thought feasible. We elected to angle the access tract both laterally and cranially in order to course below the 12th rib, but still enter the upper pole calix. Although this tract entered the calix obliquely, instruments were readily passed after sheath placement and the stone was completely removed. An ultrasonic lithotripsy device and suction was used to fragment and evacuate the stone. Postoperatively there were no intrathoracic or pulmonary complications. The direct percutaneous approach to the upper pole of the kidney requires careful methodology based on a clear understanding of the anatomy of the kidney and surrounding structures. For upper-pole renal calculi located above the 12th rib that are not amenable to shockwave lithotripsy or ureteroscopy, a subcostal angled percutaneous approach can be safely made in selected cases. With this method, the risk of intrathoracic complications may be reduced.
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.
Methods. The study group consisted of 120 consecutive patients who underwent radical prostatectom... more Methods. The study group consisted of 120 consecutive patients who underwent radical prostatectomy for clinically localized prostate cancer. Preoperative plasma IGF-I levels were measured using the DSL-IGF-I Elisa assay. Surgically removed prostate specimens were analyzed ...
In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence af... more In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence after radiotherapy who received single or repeated cycles of replication-deficient adenoviral vector (ADV)-mediated herpes simplex virus-thymidine kinase (HSV-tk) plus ganciclovir (GCV) in situ gene therapy with respect to serum PSA levels, alterations in immune cells, and numbers of apoptotic cells in needle biopsies. An initial cycle of HSV-tk plus GCV gene therapy caused a significant prolongation of the mean serum PSA-doubling time (PSADT) from 15.9 to 42.5 months (p = 0.0271) and in 28 of the injected patients (77.8%) there was a mean PSA reduction (PSAR) of 28%. It took a mean of 8.5 months for the PSA to return to the initial PSA (TR-PSA) value. A repeated cycle of gene therapy failed to significantly extend PSADT but did result in significant increases in PSAR (29.4%) and TR-PSA (10.5 months). Moderately increased serum adenovirus antibody titers were generally observed 2 weeks after initial vector injection. Also at this time there was a statistically significant increase in the mean percent of CD8(+) T cells positive for the HLA-DR marker of activation in peripheral blood (p = 0.0088). Studies using prostate biopsies obtained at the same time point demonstrated that vector DNA was detectable by PCR in most samples yet all patients remained positive for prostate cancer in at least one biopsy core. Further analysis demonstrated a correlation between the level of CD8(+) cells and the number of apoptotic cells in biopsies containing cancer cells (p = 0.042). We conclude that repeated cycles of in situ HSV-tk plus GCV gene therapy can be administered to prostate cancer patients who failed radiotherapy and have a localized recurrence. Biological responses to this experimental therapy including increases in PSADT, PSAR, and TR-PSA, and activated CD8(+) T cells present in the peripheral blood, were demonstrated. Interestingly, the density of CD8(+) cells in posttreatment biopsies correlated with the number of apoptotic cells.
Wilm's tumor, or nephroblastoma, is a common renal tumor among children. Few cases of Wilm... more Wilm's tumor, or nephroblastoma, is a common renal tumor among children. Few cases of Wilm's tumor have been reported in women during pregnancy. The authors present a rare case of a pregnant female, who underwent laparoscopic excision of a large Wilm's tumor. The authors have also provided a review of the current literature.
To test whether preoperative insulin-like growth factor (IGF)-I levels could predict pathologic s... more To test whether preoperative insulin-like growth factor (IGF)-I levels could predict pathologic stage and prognosis of prostate cancer in patients undergoing radical prostatectomy. The study group consisted of 120 consecutive patients who underwent radical prostatectomy for clinically localized prostate cancer. Preoperative plasma IGF-I levels were measured using the DSL-IGF-I Elisa assay. Surgically removed prostate specimens were analyzed pathologically, using a whole-mount step-section technique. Preoperative plasma IGF-I levels were compared with final pathologic parameters and with prostate-specific antigen (PSA) progression-free survival. Preoperative IGF-I levels in this cohort were also compared with IGF-I levels measured in 20 healthy men without any cancer and in 10 men with untreated, metastatic prostate cancer. Plasma IGF-I levels predicted neither organ-confined disease (P = 0.5611) nor the risk of PSA progression (P = 0.8125) at a median follow-up of 48.6 months after prostatectomy. Furthermore, IGF-I levels did not correlate with preoperative PSA level (P = 0. 2811) or final Gleason score (P = 0.4906). IGF-I levels in radical prostatectomy patients were not significantly higher than those in healthy subjects or in patients with metastatic disease (mean 156.7 +/- 66 ng/mL, 148.6 +/- 49 ng/mL, and 148.6 +/- 93 ng/mL, respectively; P = 0.8442). Circulating IGF-I levels may predict the future risk of developing prostate cancer, but our study found no association with other established markers of biologically aggressive disease or with disease progression in patients with clinically localized prostate cancer.
Purpose-We examined the utility and potential limitations of MEMS (Microelectro-mechanical system... more Purpose-We examined the utility and potential limitations of MEMS (Microelectro-mechanical systems) based spectral-domain cystoscopic optical coherence tomography (COCT) to improve the diagnosis of early bladder cancer. Materials and Methods-OCT catheter was integrated into the single instrument channel of a 22Fr cystoscope to permit white-light guided COCT over a large field of view of 4.6mm wide and 2.1mm deep per scan at 8 frames/s and 10um resolution. Intraoperative COCT diagnosis was performed in 56 patients, with a total of 110 lesions examined and compared with biopsied histology. Results-The overall sensitivity of COCT (94%) was significantly higher than cystoscopy (75%, p=0.02) and voided cytology (59%, p=0.005); the major enhancement over cystoscopy was for lowgrade pTa-1 cancer and carcinoma in situ (p<0.018). The overall specificity of COCT (81%) was comparable to voided cytology (88.9%, p=0.49), but significantly higher than cystoscopy (62.5%, p=0.02). Conclusions-MEMS-based COCT, owing to its high resolution and detection sensitivity and large field of view, offers great potential for 'optical biopsy' to enhance the diagnosis of non-papillary bladder tumors and their recurrences and to guide bladder tumor resection.
Medical Imaging 2004: Physiology, Function, and Structure from Medical Images, 2004
We propose a new partial volume (PV) segmentation scheme to extract bladder wall for computer aid... more We propose a new partial volume (PV) segmentation scheme to extract bladder wall for computer aided detection (CAD) of bladder lesions using multispectral MR images. Compared with CT images, MR images provide not only a better tissue contrast between bladder wall and bladder lumen, but also the multispectral information. As multispectral images are spatially registered over three-dimensional space, information extracted from them is more valuable than that extracted from each image individually. Furthermore, the intrinsic T 1 and T 2 contrast of the urine against the bladder wall eliminates the invasive air insufflation procedure. Because the earliest stages of bladder lesion growth tend to develop gradually and migrate slowly from the mucosa into the bladder wall, our proposed PV algorithm quantifies images as percentages of tissues inside each voxel. It preserves both morphology and texture information and provides tissue growth tendency in addition to the anatomical structure. Our CAD system utilizes a multi-scan protocol on dual (full and empty of urine) states of the bladder to extract both geometrical and texture information. Moreover, multi-scan of transverse and coronal MR images eliminates motion artifacts. Experimental results indicate that the presented scheme is feasible towards mass screening and lesion detection for virtual cystoscopy (VC).
SummaryDevelopment of metastases requires cancer cells to breach underlying basement membrane, mi... more SummaryDevelopment of metastases requires cancer cells to breach underlying basement membrane, migrate through interstitial stroma and gain access to blood or lymphatic vessels. Membrane type 1-matrix metalloproteinase (MT1-MMP) has been linked with these processes. Expression of MT1-MMP in human prostate cancer correlates with the stage of this disseminated disease. The mechanism underlying this observation, however, still remains to be understood. To study the role of MT1-MMP in prostate cancer dissemination, endogenous and recombinant MT1-MMP expressed in human prostate cancer cell lines (DU-145 and LNCaP) were examined. Using FITC-labeled Ma-trigel, a soluble basement membrane extract coated coverslips, LNCaP cells stably expressing a chimera of MT1-MMP and Green Fluorescent Protein (MT1-GFP) degraded Matrigel and readily migrated over degraded substrates. The degradation of Matrigel by LNCaP cells expressing MT1-GFP was sensitive to MMP inhibitors, CT-1746 and TIMP-2, but not T...
Purpose: Prostate cancer is the most common male malignancy and the second leading cause of male ... more Purpose: Prostate cancer is the most common male malignancy and the second leading cause of male cancer death; therefore, there is urgent necessity for noninvasive assays for early detection of prostate cancer. Obtaining prostate tumor samples surgically is problematic because the malignancy is heterogeneous and multifocal and early-stage tumors are nonpalpable. In contrast, exfoliated cells represent the cancer status of the entire gland better due to the general tendency of cancer cells to exfoliate into biological fluids. The purpose of this study was to clarify whether quantitative analysis of telomerase activity in exfoliated cells in urine could serve as a reliable molecular marker of prostate malignancy. Experimental Design: We analyzed prospectively post-prostatic examination–exfoliated cells from the urine of 56 patients undergoing routine prostate screening. Epithelial cells were isolated and enriched by immunomagnetic separation. Telomerase activity was analyzed by quanti...
Entry into the retroperitoneal space during Minimally Invasive Transforaminal Lumbar Interbody Fu... more Entry into the retroperitoneal space during Minimally Invasive Transforaminal Lumbar Interbody Fusion (MI-TLIF) presents a rare possibility of iatrogenic ureteral injury. Rare complications of ureteral injury after previous open posterior spinal surgery have been reported however there is a paucity of reports after a minimally invasive technique. We now describe a case of ureteral injury after MI-TLIF.
Recent data indicate a decline in the urological education of third and fourth year medical stude... more Recent data indicate a decline in the urological education of third and fourth year medical students. To determine if this decline has an impact on the treatment of patients we performed a survey to evaluate the general level of knowledge, attitudes and practices with regard to common urological issues seen in a general medical practice among medical students and faculty involved in primary care at an academic institution. Materials and Methods: A confidential questionnaire was distributed to attendings, residents and fellows, and the clinical medical students at our academic institution to ascertain how they evaluate and treat patients with common urological complaints. All responses were entered into SPSS® statistical software. Results: A total of 300 surveys were distributed, 150 of which were returned with complete information for data analysis. Knowledge with regard to various conditions including hematuria, recognition of an age specific abnormality in serum prostate specific antigen and overactive bladder was low for all groups. Furthermore, respondents demonstrated a low likelihood of requesting formal urological evaluation for these conditions. Exposure to a urology elective in medical school had a positive impact on some areas of urological evaluation. Conclusions: General urological knowledge with regard to the primary care setting is insufficient. The potential for impact on patient care is enormous. These data highlight the need for a definitive urological curriculum in medical school as well as continued education at the resident and faculty level with regard to evaluation, management and recognition of when to request formal urological evaluation in the primary care setting.
Purpose: The etiology of voiding dysfunction was determined in men after a cerebrovascular accide... more Purpose: The etiology of voiding dysfunction was determined in men after a cerebrovascular accident who were at risk for obstructive uropathy to evaluate whether the cause of voiding dysfunction could be predicted by the type (obstructive or irritative) or onset of symptoms. Materials and Methods: We evaluated 38 men with complaints of voiding dysfunction following a cerebrovascular accident. All patients were of the age when bladder outlet obstruction secondary to benign prostatic hyperplasia would otherwise be prevalent. After a comprehensive history and physical examination, all patients underwent multichannel urodynamic studies at a medium fill rate (20 to 50 ml. per minute). Findings were classified by the Abrams-Griffiths nomogram as obstruction, no obstruction or equivocal. Results: Mean patient age was 70 years (range 54 to 87). Patients were grouped according to the presenting voiding complaints (purely irritative in 42%, purely obstructive in 34% or mixed in 24%). In 34 patients (89%) the onset of symptoms paralleled the occurrence of the cerebrovascular accident. Detrusor hyperreflexia was noted in 82% of the patients. There was no statistically significant difference in the occurrence of detrusor hyperreflexia among the 3 symptom groups (Fisher's exact test). Pressure-flow analysis clearly showed obstruction in 24 patients (63%), no obstruction in 9 (24%) and equivocal results in 5 (13%) according to the nomogram. There was no statistically significant difference in the incidence of obstruction among the 3 symptom groups (Fisher's exact test). Conclusions: Presenting symptoms did not predict the urodynamic findings of bladder outlet obstruction or detrusor hyperreflexia. The significant incidence of onset of symptoms aRer stroke suggests that the cerebrovascular accident induced voiding dysfunction in the face of preexisting bladder outlet obstruction may exacerbate the symptoms of the latter condition or vice versa.
Percutaneous upper pole access may be obtained via the supracostal or subcostal approach. The mor... more Percutaneous upper pole access may be obtained via the supracostal or subcostal approach. The more cranial the location of the percutaneous nephrostomy tract, the greater the risk of incurring intrathoracic complications. We describe a technique for safely accessing the upper pole calix via a subcostal approach, even when the stone is located well above the 12th rib. In our patient the stone was located between the 11th and 12th ribs, and the upper pole extended to above the 10th rib. A 78-year-old man with multiple medical problems had a symptomatic upper right pole stone located between 11th and 12th ribs. Due to its size (3 x 2.2 cm), neither a ureteroscopic nor shockwave approach was thought feasible. We elected to angle the access tract both laterally and cranially in order to course below the 12th rib, but still enter the upper pole calix. Although this tract entered the calix obliquely, instruments were readily passed after sheath placement and the stone was completely removed. An ultrasonic lithotripsy device and suction was used to fragment and evacuate the stone. Postoperatively there were no intrathoracic or pulmonary complications. The direct percutaneous approach to the upper pole of the kidney requires careful methodology based on a clear understanding of the anatomy of the kidney and surrounding structures. For upper-pole renal calculi located above the 12th rib that are not amenable to shockwave lithotripsy or ureteroscopy, a subcostal angled percutaneous approach can be safely made in selected cases. With this method, the risk of intrathoracic complications may be reduced.
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.
Methods. The study group consisted of 120 consecutive patients who underwent radical prostatectom... more Methods. The study group consisted of 120 consecutive patients who underwent radical prostatectomy for clinically localized prostate cancer. Preoperative plasma IGF-I levels were measured using the DSL-IGF-I Elisa assay. Surgically removed prostate specimens were analyzed ...
In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence af... more In an extended phase I/II study we evaluated 36 prostate cancer patients with local recurrence after radiotherapy who received single or repeated cycles of replication-deficient adenoviral vector (ADV)-mediated herpes simplex virus-thymidine kinase (HSV-tk) plus ganciclovir (GCV) in situ gene therapy with respect to serum PSA levels, alterations in immune cells, and numbers of apoptotic cells in needle biopsies. An initial cycle of HSV-tk plus GCV gene therapy caused a significant prolongation of the mean serum PSA-doubling time (PSADT) from 15.9 to 42.5 months (p = 0.0271) and in 28 of the injected patients (77.8%) there was a mean PSA reduction (PSAR) of 28%. It took a mean of 8.5 months for the PSA to return to the initial PSA (TR-PSA) value. A repeated cycle of gene therapy failed to significantly extend PSADT but did result in significant increases in PSAR (29.4%) and TR-PSA (10.5 months). Moderately increased serum adenovirus antibody titers were generally observed 2 weeks after initial vector injection. Also at this time there was a statistically significant increase in the mean percent of CD8(+) T cells positive for the HLA-DR marker of activation in peripheral blood (p = 0.0088). Studies using prostate biopsies obtained at the same time point demonstrated that vector DNA was detectable by PCR in most samples yet all patients remained positive for prostate cancer in at least one biopsy core. Further analysis demonstrated a correlation between the level of CD8(+) cells and the number of apoptotic cells in biopsies containing cancer cells (p = 0.042). We conclude that repeated cycles of in situ HSV-tk plus GCV gene therapy can be administered to prostate cancer patients who failed radiotherapy and have a localized recurrence. Biological responses to this experimental therapy including increases in PSADT, PSAR, and TR-PSA, and activated CD8(+) T cells present in the peripheral blood, were demonstrated. Interestingly, the density of CD8(+) cells in posttreatment biopsies correlated with the number of apoptotic cells.
Wilm's tumor, or nephroblastoma, is a common renal tumor among children. Few cases of Wilm... more Wilm's tumor, or nephroblastoma, is a common renal tumor among children. Few cases of Wilm's tumor have been reported in women during pregnancy. The authors present a rare case of a pregnant female, who underwent laparoscopic excision of a large Wilm's tumor. The authors have also provided a review of the current literature.
To test whether preoperative insulin-like growth factor (IGF)-I levels could predict pathologic s... more To test whether preoperative insulin-like growth factor (IGF)-I levels could predict pathologic stage and prognosis of prostate cancer in patients undergoing radical prostatectomy. The study group consisted of 120 consecutive patients who underwent radical prostatectomy for clinically localized prostate cancer. Preoperative plasma IGF-I levels were measured using the DSL-IGF-I Elisa assay. Surgically removed prostate specimens were analyzed pathologically, using a whole-mount step-section technique. Preoperative plasma IGF-I levels were compared with final pathologic parameters and with prostate-specific antigen (PSA) progression-free survival. Preoperative IGF-I levels in this cohort were also compared with IGF-I levels measured in 20 healthy men without any cancer and in 10 men with untreated, metastatic prostate cancer. Plasma IGF-I levels predicted neither organ-confined disease (P = 0.5611) nor the risk of PSA progression (P = 0.8125) at a median follow-up of 48.6 months after prostatectomy. Furthermore, IGF-I levels did not correlate with preoperative PSA level (P = 0. 2811) or final Gleason score (P = 0.4906). IGF-I levels in radical prostatectomy patients were not significantly higher than those in healthy subjects or in patients with metastatic disease (mean 156.7 +/- 66 ng/mL, 148.6 +/- 49 ng/mL, and 148.6 +/- 93 ng/mL, respectively; P = 0.8442). Circulating IGF-I levels may predict the future risk of developing prostate cancer, but our study found no association with other established markers of biologically aggressive disease or with disease progression in patients with clinically localized prostate cancer.
Purpose-We examined the utility and potential limitations of MEMS (Microelectro-mechanical system... more Purpose-We examined the utility and potential limitations of MEMS (Microelectro-mechanical systems) based spectral-domain cystoscopic optical coherence tomography (COCT) to improve the diagnosis of early bladder cancer. Materials and Methods-OCT catheter was integrated into the single instrument channel of a 22Fr cystoscope to permit white-light guided COCT over a large field of view of 4.6mm wide and 2.1mm deep per scan at 8 frames/s and 10um resolution. Intraoperative COCT diagnosis was performed in 56 patients, with a total of 110 lesions examined and compared with biopsied histology. Results-The overall sensitivity of COCT (94%) was significantly higher than cystoscopy (75%, p=0.02) and voided cytology (59%, p=0.005); the major enhancement over cystoscopy was for lowgrade pTa-1 cancer and carcinoma in situ (p<0.018). The overall specificity of COCT (81%) was comparable to voided cytology (88.9%, p=0.49), but significantly higher than cystoscopy (62.5%, p=0.02). Conclusions-MEMS-based COCT, owing to its high resolution and detection sensitivity and large field of view, offers great potential for 'optical biopsy' to enhance the diagnosis of non-papillary bladder tumors and their recurrences and to guide bladder tumor resection.
Medical Imaging 2004: Physiology, Function, and Structure from Medical Images, 2004
We propose a new partial volume (PV) segmentation scheme to extract bladder wall for computer aid... more We propose a new partial volume (PV) segmentation scheme to extract bladder wall for computer aided detection (CAD) of bladder lesions using multispectral MR images. Compared with CT images, MR images provide not only a better tissue contrast between bladder wall and bladder lumen, but also the multispectral information. As multispectral images are spatially registered over three-dimensional space, information extracted from them is more valuable than that extracted from each image individually. Furthermore, the intrinsic T 1 and T 2 contrast of the urine against the bladder wall eliminates the invasive air insufflation procedure. Because the earliest stages of bladder lesion growth tend to develop gradually and migrate slowly from the mucosa into the bladder wall, our proposed PV algorithm quantifies images as percentages of tissues inside each voxel. It preserves both morphology and texture information and provides tissue growth tendency in addition to the anatomical structure. Our CAD system utilizes a multi-scan protocol on dual (full and empty of urine) states of the bladder to extract both geometrical and texture information. Moreover, multi-scan of transverse and coronal MR images eliminates motion artifacts. Experimental results indicate that the presented scheme is feasible towards mass screening and lesion detection for virtual cystoscopy (VC).
SummaryDevelopment of metastases requires cancer cells to breach underlying basement membrane, mi... more SummaryDevelopment of metastases requires cancer cells to breach underlying basement membrane, migrate through interstitial stroma and gain access to blood or lymphatic vessels. Membrane type 1-matrix metalloproteinase (MT1-MMP) has been linked with these processes. Expression of MT1-MMP in human prostate cancer correlates with the stage of this disseminated disease. The mechanism underlying this observation, however, still remains to be understood. To study the role of MT1-MMP in prostate cancer dissemination, endogenous and recombinant MT1-MMP expressed in human prostate cancer cell lines (DU-145 and LNCaP) were examined. Using FITC-labeled Ma-trigel, a soluble basement membrane extract coated coverslips, LNCaP cells stably expressing a chimera of MT1-MMP and Green Fluorescent Protein (MT1-GFP) degraded Matrigel and readily migrated over degraded substrates. The degradation of Matrigel by LNCaP cells expressing MT1-GFP was sensitive to MMP inhibitors, CT-1746 and TIMP-2, but not T...
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Papers by Howard Adler