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T Loch

Publications and source records attributed to T Loch.

At least 19 recordsLinked to original sources
PubMed2006

[Innovative approaches in prostate cancer ultrasound].

Today, systematic random biopsies have virtually replaced ultrasound as an imaging tool in the early diagnosis and staging of prostate cancer. Transrectal ultrasonography (TRUS) is now utilized almost only to guide the biopsy needle into the correct anatomical or topographical region of the prostate. Nevertheless, a large number of clinically significant carcinomas are not discovered despite of multiple systematic biopsies. This has led to a dramatic increase in the number of biopsy samples taken, with 6, 10, 12 to 143 being taken during one session depending on the site. Newer modalities and innovative techniques are being investigated in order to accurately identify patients with prostate cancer at different stages of the disease. Innovative ultrasonography techniques may improve the diagnosis and staging of current imaging techniques.

Biopsy, Needle↗
PubMed2006

[Innovative imaging in urology: fascination and future. Yesterday, today, and tomorrow].

In contrast to other countries (e.g., USA) the German urologist routinely utilizes imaging in order to evaluate urological disorders. Ultrasound as a basic tool has acquired importance similar to the physical examination or the patient history. Because of its minimal invasiveness and low cost, it is increasingly utilized as a first-line exam.In correlation with the patient history and laboratory data more invasive imaging studies are performed and in unclear cases or in the preoperative work-up more extensive imaging procedures like computed tomography (CT) or magnetic resonance imaging (MRI) are utilized. Even in emergency situations the urologist is able to guide interventions under ultrasound or conventional X-ray guidance (e.g., percutaneous drainage of dilated kidney), which resulted in a much lower complication rate of the various procedures. In those cases in which ultrasound is technically infeasible or in unclear cases CT and MRI are used as problem-solving procedures and are able to give the correct diagnosis in a large percentage of cases.After a brief historical overview, newer modalities and innovative techniques are explored and presented. Assuming that these innovative approaches lead to more accurate diagnosis and staging of various neoplastic and nonneoplastic conditions, treatment can be performed in earlier stages of diseases and better stage-adapted treatment can be offered to the patients.

Diagnostic Imaging↗
PubMed2004

[Computerized supported transrectal ultrasound (C-TRUS) in the diagnosis of prostate cancer].

In the diagnosis of prostate cancer digital rectal examination and transrectal ultrasound (TRUS) are the most utilized methods for clinical evaluation. However, both methods are not able to differentiate between benign and malignant findings with a high amount of certainty. Nevertheless, TRUS is an excellent tool to guide biopsies in practically any region of the prostate. The most significant problem of visual TRUS interpretation is the lack of specificity, especially being an inexperienced user. In order to enhance the diagnostic capabilities of TRUS we developed a computerized analysis of the TRUS signal information (C-TRUS/ANNA), which was validated by the pathohistologic findings of radical prostatectomies. The question was asked: Can C-TRUS detect cancer that has been missed by even multiple systematic biopsies? The entrance criteria was prior negative systematic random biopsies regardless of number of biopsy sessions or number of individual biopsy cores. Five C-TRUS subvisual algorithms were utilized to evaluate the information of the ultrasound signal. The most suspicious regions were marked by C-TRUS and biopsied by guiding a needle into that specific location. In this study 132 with a history of 6-72 negative systematic random biopsies (median: 12 cores) were evaluated by C-TRUS. The PSA ranged from 3.1-36 ng/ml with a median of 9.01 ng/ml. C-TRUS detected in 66 (50%) of these 132 patients cancer by targeted biopsies. In thes 66 men the median number of negative biopsy sessions were two and a median of 12 biopsy cores had been taken. From the literature, we would expect a cancer detection rate in this group with systematic sextant biopsies of about 7%. Only five of the detected carcinomas showed a Gleason Score (GS) of 5, were as 25 had a GS of 6, 22 a GS of 7 and 15 a GS above 7. The results of this prospective clinical trail indicate that C-TRUS is able to identify clinically significant cancers that were missed by even multiple systematic random biopsies. In addition, the concept of searching for strategies that utilize expertise and refinement of imaging modalities is supported rather than just elevating the number of random biopsies (i.e. 141 cores in one session).

Aged↗
PubMed2004

Adrenal metastases in 1635 patients with renal cell carcinoma: outcome and indication for adrenalectomy.

PURPOSE: Routine removal of the ipsilateral adrenal gland in patients with renal cell carcinoma who undergo nephrectomy has been a matter of dispute. In a retrospective study we screened for subgroups of patients with renal cell carcinoma from a large single center patient population who may have benefited from ipsilateral adrenalectomy. MATERIALS AND METHODS: Radical nephrectomy was performed in 1635 patients at a single institution between 1980 and 2000. A total of 1010 patients underwent radical nephrectomy plus ipsilateral adrenalectomy, whereas in 625 no simultaneous adrenalectomy was performed. Numerous clinical and histopathological parameters were investigated by univariate and multivariate statistical methods for their predictive value in regard to cancer specific survival. RESULTS: Metastases in the adrenal gland were found in 5.5% of patients (56 of 1010) undergoing nephrectomy with adrenalectomy. Of 30 patients with adrenal metastasis and preoperative computerized tomography/magnetic resonance imaging 23 were found to have histological evidence of cancer, approaching a false-negative rate of 23.3%. All patients with false-negative computerized tomography/magnetic resonance imaging had a primary tumor of greater than 4 cm. Patients with adrenal metastases predominately had pT3 or greater tumor stage (82%). Cancer specific survival rates (75% vs 73% for adrenalectomy vs no adrenalectomy) and postoperative complications rates (7% vs 8%) did not differ significantly between the 2 groups. The prognosis in patients with a solitary adrenal metastasis (18 of 56) was more favorable than in patients with additional metastatic sites (38 of 56). CONCLUSIONS: Adrenal metastases from primary renal cell carcinoma were found significantly more often in patients with advanced tumor stages. Ipsilateral adrenalectomy should be recommended for all resectable renal cell carcinoma with a primary tumor of greater than 4 cm or with nonorgan confined tumor stages (T3 or greater) since a false-negative rate of about 20% can be expected with current imaging techniques.

Adrenal Gland Neoplasms↗
PubMed2003

[Gemcitabine/cisplatin vs. MVAC. 5 year survival outcome of the phase III study of chemotherapy of advanced urothelial carcinoma in Germany].

Of 405 patients with stage IV transitional cell carcinoma from an international multicenter phase III trial, 70 were randomized in Germany to receive either gemcitabine/cisplatin or standard MVAC systemic chemotherapy for locally advanced or metastatic urothelial cancer. Overall survival as the primary endpoint of the study was similar in both arms (median survival GC 15.4 months vs MVAC 16.1 months), as were tumor-specific survival and time to progressive disease. In the intent-to-treat analysis, the 5-year overall survival rate was 10% for patients randomized to GC and 18% randomized to MVAC. Tumor overall response rates (GC 54%, MVAC 53%) were similar. The toxic death rate was 0% in the GC arm and 3% (one patient) in the MVAC arm. Significantly more GC than MVAC patients experienced grade 3/4 anemia (GC 52%, MVAC 20%) with significantly more red blood cell transfusions in the GC arm.Significantly more GC than MVAC patients had grade 3/4 thrombocytopenia (GC 54%, MVAC 17%) without grade 3/4 hemorrhage or hematuria in either arm. More MVAC patients experienced grade 3/4 neutropenia (GC 56%, MVAC 61%, p=1.000), neutropenic or leukopenic fever (GC 0%, MVAC 10%, p=0.237), mucositis (GC 0%, MVAC 7%, p=0.495), and alopecia (GC 6%, MVAC 36%, p=0.004). GC represents a reasonable alternative for the palliative treatment of patients with locally advanced and metastatic transitional cell carcinoma. Sustained long-term survival was only found for patients with locally advanced cancer, lymphatic metastases, or solitary distant metastasis but not for visceral metastatic disease.

Adult↗
PubMed2003

[Is fiber optic hepatovenous oximetry useful in patients undergoing elective partial liver resection?].

The validity of continuous measurement of hepatic venous oxygen saturation using a fibreoptic technique was investigated and set in correlation with intermittent measurements of saturation in hepatic venous blood in patients undergoing elective partial liver resection (pLR). Eleven patients (4 m/7 f, average age: 62.6 +/- 11.6 years) were included in the study after approval by the Ethics Committee of the University of Leipzig. A fibre-optic heparinized flow-directed pulmonary catheter (5.5-F) was inserted through the right internal jugular vein into the hepatic vein after induction of balanced anaesthesia (isoflurane/alfentanil). The position of the tip of the catheter was verified by fluoroscopic guidance. The oxygen saturation in the hepatic vein measured by the fibre-optic method and by blood-gas analysis (ShvO2) was compared at nine defined measuring points after in-vivo calibration (baseline). The ShvO2 decreased nonsignificantly from 84.4 +/- 10.4% to 77.1 +/- 19.1% during occlusion of the vessels in the liver hilus (Pringle's manoeuvre). The ShvO2 measured by the fibre-optic method and by blood-gas analysis correlated well (r = 0.815, p < 0.001). The limitations of the method result from artefacts based on surgical manipulations in the portal region (compression of hepatic veins, luxation of the liver). These artefacts can be differentiated by analysis of the pressure curves in the hepatic vein. Nevertheless, fibreoptic hepatovenous oxymetry seems to be a feasible method for continuous monitoring of the ShvO2 under intraoperative conditions in patients undergoing partial liver resection. Ischaemic situations of the liver can be detected and treated early. Additional information can be obtained from analyses of parameters in the hepatovenous blood.

Aged↗
PubMed2001

[High dosage brachytherapy and external irradiation of localized prostate carcinoma--results at the Kiel University Clinic].

To evaluate a new therapy protocol for local dose escalation by high dose rate (HDR) brachytherapy for survival, morbidity and prognostic variables in men with localized prostate cancer. The prospectively recorded files of 189 men aged in median 69 years with a mean follow-up of 6 years (12-143 months) receiving curatively intended combined high dose rate (HDR) 192-iridium-brachytherapy (BT) and external beam radiation (EBR) for locally confined prostate cancer were analyzed. Mean age was 68.2 (range 44-84 years). Hundred and twenty-seven patients had T1-2 tumors, and 62 patients had T3-tumors. The total planned dose applied by external beam radiation was 50 Gy in the pelvis, and 40 Gy in the prostate by in-field-dose modification. The HDR-brachytherapy was delivered in two fractions. The dose per fraction amounted 15 Gy. Mean survival was 6 years (range 12-143 months), 76.7% of the patients survived and 86.3% were disease-free. The biochemical non-evidence of disease rate (BNED) was 78%. Univariate survival analysis revealed that low stage (T1-2), low grade (G1-2), normal PSA status after radiation therapy, and no adjuvant hormonal treatment were associated with long survival. However, the stratification for adjuvant hormonal treatment was not according to random. In multivariate analyses PSA status was an independent prognostic factor. The six year results confirm that local dose escalation by HDR-brachytherapy and external beam radiation is curative in men with locally confined prostate cancer. The results are especially in high risk patients encouraging.

Aged↗
PubMed2001

Prostate-specific antigen in female urine: a prospective study involving 217 women.

OBJECTIVES: Histomorphologic studies have provided evidence of prostate-specific antigen (PSA)-producing tissue in the female urethra. Some urine samples from women in a small series were positive for PSA, but no systematic investigation of this subject has been done to date. METHODS: In a prospective study, we analyzed whether PSA occurs in the urine of women and what factors induce detectable PSA levels. The urine samples of 217 women were analyzed (Hybritech-Tandem E-PSA) under standardized conditions. The impact of urine pH and volume was investigated, and the results were correlated with clinical data (age, residual urine, urinary tract infection and prior sexual intercourse within 48 hours). RESULTS: A positive PSA level greater than the detection limit of 0.1 ng/mL was found in 11% of the analyzed samples; their mean value was 0.29 ng/mL. pH correction did not result in a significant difference. The voiding volume had no influence on the PSA level. Among the cases of detectable PSA, women younger than 50 years of age (n = 14) had a mean PSA of 0.34 ng/mL and those older than 50 years (n = 9) a mean of 0.23 ng/mL. One of 9 women with and 22 of 208 women without residual urine volume had a detectable PSA level, as did 0 of 20 with and 23 of 197 women without urinary tract infection, and 3 of 7 with and 20 of 210 women without prior sexual intercourse within the previous 48 hours. None of the differences were significant. CONCLUSIONS: A urine PSA level was detected in 11% of all women studied, with PSA values apparently age dependent. Any urine portion is suitable for analysis. No influence was determined for residual urine volume or urinary tract infection. Sexual intercourse may cause detectable PSA values, but the data of this study did not provide sufficient evidence for this hypothesis.

Adult↗
PubMed2001

Cytokeratin-20 reverse-transcriptase polymerase chain reaction as a new tool for the detection of circulating tumor cells in peripheral blood and bone marrow of bladder cancer patients.

OBJECTIVES: Systemic progression is the prevalent form of bladder tumor recurrence after radical cystectomy. The ability to detect circulating tumor cells in peripheral blood or bone marrow could be of prognostic value for the disease with the consequence of early adjuvant chemotherapy. We established a sensitive and specific method using a double cytokeratin-20 (CK-20) reverse-transcriptase polymerase chain reaction (RT-PCR) to detect circulating bladder cancer cells in venous blood and bone marrow MATERIAL AND METHODS: The sensitivity of the detection method was determined by a serial dilution of bladder cancer cells from the cell line HT1376 in whole blood. Bone marrow from 20 bladder cancer patients was drawn prior to radical cystectomy and CK-20 cDNA was amplified by RT-PCR. Additionally, pre- and postoperative venous blood samples from 11 of these patients with bone marrow aspirates and 9 patients undergoing only transurethral resection of the bladder as well as blood samples of 25 healthy volunteers were investigated by CK-20 RT-PCR. RESULTS: The detection limit of the method was 2 bladder cancer cells/ml whole blood containing one million peripheral blood mononuclear cells. The positive detection rate in bone marrow was 7 of 20 (35%) for bladder cancer patients of all stages. However, investigation of the preoperatively collected venous blood samples from 20 patients revealed onyl 2 positive findings, belonging to advanced tumor stages pT4pN0M0 and pT3pN2M0. In contrast, CK-20 was detected in 3 of 20 postoperatively collected venous blood samples from patients with low tumor stages (pTaNXM0 and pT1NXM0) as well as from 1 patient with pelvic lymph node metastases (pT3apN2M0). All venous blood samples of the control group (n = 25) were negative for CK-20. CONCLUSION: The detection of circulating bladder tumor cells in venous blood and bone marrow by the CK-20 RT-PCR is a promising approach that could improve risk assessment and the identification of bladder cancer patients who would benefit from adjuvant chemotherapy.

Adult↗
PubMed2001

Quantitative RT-PCR assay for mRNA of VEGF and histone H4 in the determination of proliferative and angiogenic activity in vulvar pathology.

Proliferative and angiogenic activity of tissue specimens taken from women with various vulvar pathologies were evaluated by determining the number of mRNA VEGF molecules and H4 histone mRNA molecules, by means of the QRT-PCR (TaqMan) technique. Following a cluster analysis the results, where normalised. Euclidean distances were used, all the cases were classified into three groups of pathologies. Group I included low degree vulvar pathologies, group II included high degree vulvar pathologies and group III included vulvar pathologies with high proliferative and angiogenic activity. Significant differences were found in the proliferative and angiogenic activity between groups I and III, and between groups II and III, while no statistically significant differences were found between groups I and II.

Carcinoma in Situ↗
PubMed2000

Long term follow-up of combined radiochemotherapy for locally advanced bladder carcinoma.

BACKGROUND: The 5- and 10-year survival rates and the toxicity of combined radiochemotherapy for 53 consecutive patients with locally advanced bladder carcinoma were studied in a noncomparative trial. METHODS: Between November 1986 and October 1987, 53 consecutive patients (mean age, 68 years) with muscle invasive and/or locally advanced bladder carcinoma were treated by simultaneous chemotherapy and hyperfractionated irradiation. Radiation was administered during the first to fourth week and during the ninth to tenth week as an interrupted treatment protocol. Cisplatin and epirubicin were used as radiosensitizers before radiation. The maximum dose of irradiation was 57.6 grays. RESULTS: Of 53 patients, 45 completed the planned treatment course. Causes for discontinuing therapy in 8 patients were pronounced myelosuppression (n = 2), severe gastrointestinal symptoms (n = 2), nephrotoxicity (n = 1), and severe radioproctitis (n = 1). Two additional patients stopped therapy due to vascular diseases independent of treatment-related toxicity. The overall survival for all 53 patients was 23% after 5 years and 8% after 10 years. Cause specific survival was 36% after 5 years and 29% after 10 years. Four patients are still alive after 10 years without disease progression. One of them received incomplete therapy due to toxicity. All four patients underwent transurethral resections for superficial, local tumor recurrences. CONCLUSIONS: The poor prognosis group of patients with invasive and/or locally advanced bladder carcinoma was found to have a limited disease specific survival after combined radiochemotherapy.

Adult↗
PubMed2000

[Improvement of transrectal ultrasound. Artificial neural network analysis (ANNA) in detection and staging of prostatic carcinoma].

As a result of the enhanced clinical application of prostate specific antigen (PSA), an increasing number of men are becoming candidates for prostate cancer work-up. A high PSA value over 20 ng/ml is a good indicator of the presence of prostate cancer, but within the range of 4-10 ng/ml, it is rather unreliable. Even more alarming is the fact that prostate cancer has been found in 12-37% of patients with a "normal" PSA value of under 4 ng/ml (Hybritech). While PSA is capable of indicating a statistical risk of prostate cancer in a defined patient population, it is not able to localize cancer within the prostate gland or guide a biopsy needle to a suspicious area. This necessitates an additional effective diagnostic technique that is able to localize or rule out a malignant growth within the prostate. The methods available for the detection of these prostate cancers are digital rectal examination (DRE) and Transrectal ultrasound (TRUS). DRE is not suitable for early detection, as about 70% of the palpable malignancies have already spread beyond the prostate. The classic problem of visual interpretation of TRUS images is that hypoechoic areas suspicious for cancer may be either normal or cancerous histologically. Moreover, about 25% of all cancers have been found to be isoechoic and therefore not distinguishable from normal-appearing areas. None of the current biopsy or imaging techniques are able to cope with this dilemma. Artificial neural networks (ANN) are complex nonlinear computational models, designed much like the neuronal organization of a brain. These networks are able to model complicated biologic relationships without making assumptions based on conventional statistical distributions. Applications in Medicine and Urology have been promising. One example of such an application will be discussed in detail: A new method of Artificial Neural Network Analysis (ANNA) was employed in an attempt to obtain existing subvisual information, other than the gray scale, from conventional TRUS and to improve the accuracy of prostate cancer identification.

Adult↗
PubMed2000

Retroperitoneal mature teratoma 15 years after initial treatment of testicular mixed germ cell tumor.

We present a patient with a retroperitoneal tumor noted 15 years after treatment of a testicular mixed germ cell cancer. The patient initially underwent right-sided orchiectomy and retroperitoneal lymph node dissection for clinical stage I disease. An early relapse indicated by increasing tumor markers shortly after retroperitoneal lymph node dissection was successfully treated with five cycles of combined chemotherapy. However, 187 months after completion of chemotherapy, a symptomatic right-sided iliac mass was diagnosed. Radical surgical excision of the mass was performed and histologic examination revealed differentiated mature teratoma. This represents the longest time interval reported in the literature for a mature teratoma following treatment of a testicular germ cell tumor.

Adult↗