Christian Stock

Effect of screening sigmoidoscopy and screening colonoscopy on colorectal cancer incidence and mortality: systematic review and meta-analysis of randomised controlled trials and observational studies

Objectives To review, summarise, and compare the evidence for effectiveness of screening sigmoidoscopy and screening colonoscopy in the prevention of colorectal cancer occurrence and deaths. Design Systematic review and meta-analysis of randomised controlled trials and observational studies. Data sources PubMed, Embase, and Web of Science. Two investigators independently extracted characteristics and results of identified studies and performed standardised quality ratings. Eligibility criteria Randomised controlled trials and observational studies in English on the impact of screening sigmoidoscopy and screening colonoscopy on colorectal cancer incidence and mortality in the general population at average risk. Results For screening sigmoidoscopy, four randomised controlled trials and 10 observational studies were identified that consistently found a major reduction in distal but not proximal colorectal cancer incidence and mortality. Summary estimates of reduction in distal colorectal cancer incidence and mortality were 31% (95% confidence intervals 26% to 37%) and 46% (33% to 57%) in intention to screen analysis, 42% (29% to 53%) and 61% (27% to 79%) in per protocol analysis of randomised controlled trials, and 64% (50% to 74%) and 66% (38% to 81%) in observational studies. For screening colonoscopy, evidence was restricted to six observational studies, the results of which suggest tentatively an even stronger reduction in distal colorectal cancer incidence and mortality, along with a significant reduction in mortality from cancer of the proximal colon. Indirect comparisons of results of observational studies on screening sigmoidoscopy and colonoscopy suggest a 40% to 60% lower risk of incident colorectal cancer and death from colorectal cancer after screening colonoscopy even though this incremental risk reduction was statistically significant for deaths from cancer of the proximal colon only. Conclusions Compelling and consistent evidence from randomised controlled trials and observational studies suggests that screening sigmoidoscopy and screening colonoscopy prevent most deaths from distal colorectal cancer. Observational studies suggest that colonoscopy compared with flexible sigmoidoscopy decreases mortality from cancer of the proximal colon. This added value should be examined in further research and weighed against the higher costs, discomfort, complication rates, capacities needed, and possible differences in compliance.

Heilbronn Laparoscopic Radical Prostatectomy

Introduction: In 1999, Guillonneau and Vallancien presented a refined approach of a descending laparoscopic radical prostatectomy which based mainly on the primary access to the seminal vesicles and an improved suturing and knotting technique. Based on our own experience reconstructive laparoscopy as well as with open retropubic radical prostatectomy we have used a combined ascending/descending technique similar to open surgery. In this paper we want to describe our approach and to present the initial results with the Heilbronn technique. Materials and Methods: A transperitoneal approach is used with a W–shaped arrangement of the trocars (13–mm umbilical port, 2×10 mm medial, 2×5 mm lateral ports). After the exposure of the Retzius’ space and control of the dorsal vein complex the urethra is incised and the distal pedicles of the prostate (± the neurovascular bundle) are transsected. We now pull the apex ventrally and start with the incision at the bladder neck followed by a transvesical access to both vasa deferentia and seminal vesicles. The gland is entrapped in the Extraction Bag®. After accomplishing the posterior wall of the urethrovesical anastomosis with five interrupted sutures, the foley catheter is placed into the bladder and the bladder neck is closed. Now the prostate is extracted via the umbilical incision. From March 1999 to June 2000, we have performed 100 cases (48 pT2–, 47 pT3– and 5 pT4 tumors). The mean preoperative PSA was 26.8 (1.4–75.5) ng/ml. Two tumors were grade 1, 72 grade 2 and 26 grade 3. Median Gleason score was 6 (3–9). All specimen were inked and examined according to the Stanford protocol. Postoperative continence was evaluated using a questionnaire monitored by a colleague who was involved in surgery. Results: We had 5 conversions (rectal injury, difficult dissection, adhesion, 2× bleeding at the dorsal vein complex). The mean operating time was 278 (180–500) min., the transfusion rate 31%. One patient required reintervention due to bleeding from the right obturator fossa. 95% of the patients did not require any analgesia on the second postoperative day. Positive margins were found in 17% of the patients, of which 12 had a PSA nadir to a value of less than 0.1 ng/ml within 3 weeks after surgery. In 82 patients, the anastomosis was tight after removal of the catheter, median catheter time was 8 (6–30) days. 4% developed a stricture at the anastomotic site which could be treated by laserincision. On discharge 33% were continent, after 6 months 81%, whereas only 2 patients still suffer from grade II stress incontinence at 9 months. Conclusions: Laparoscopic radical prostatectomy is feasable but requires laparoscopic expertise. Its learning curve is still ongoing. Morbidity is low, oncological control is similar to results of open surgery, functional results are promising.

Nephrectomy: A Comparative Study between the Transperitoneal and Retroperitoneal Laparoscopic versus the Open Approach

Objectives: Different techniques have been introduced to perform laparoscopic nephrectomy using either the transperitoneal or the retroperitoneal route. However, to date only few data exist comparing the results and morbidity of these procedures as well as with the standard technique of open nephrectomy. Material and Methods: This paper compares the clinical results of 18 transperitoneal laparoscopic nephrectomies (TLN) for benign renal disease with 17 retroperitoneal laparoscopic nephrectomies (RLN) and 19 consecutive open nephrectomies (Nx). All groups were comparable in terms of indication. The analysis of clinical data included operative time, morbidity, length of analgesic use and postoperative hospital stay. Results: The mean operative time for benign disease was 206.5 for TLN, 211.2 for RLN and 117 min for open nephrectomy. Analgesic medication requirement per patient was 2 days for TLN, 1 day for RLN and 4 days for Nx while the postoperative hospital stay averaged 7 days for TLN, 6 days for RLN and 10 days for Nx. The time of convalescence was 21 days after RLN, 24 days after TLN versus 40 days after open nephrectomy. Conclusions: Our results demonstrate an overall clear advantage of a laparoscopic approach when compared to open surgery and also reveals distinct benefits of a retroperitoneal approach.

Reduced Risk of Colorectal Cancer Up to 10 Years After Screening, Surveillance, or Diagnostic Colonoscopy

BACKGROUND & AIMS Data from randomized controlled trials on the effects of screening colonoscopies on colorectal cancer (CRC) incidence and mortality are not available. Observational studies have suggested that colonoscopies strongly reduce the risk of CRC, but there is little specific evidence on the effects of screening colonoscopies. METHODS We performed a population-based case-control study of 3148 patients with a first diagnosis of CRC (cases) and 3274 subjects without CRC (controls) from the Rhine-Neckar region of Germany from 2003 to 2010. Detailed information on previous colonoscopy and potential confounding factors was collected by standardized personal interviews. Self-reported information on colonoscopies and their indications was validated by medical records. We used multiple logistic regression to assess the association between colonoscopy conducted for specific indications within the past 10 years and risk of CRC. RESULTS A history of colonoscopy was associated with a reduced subsequent risk of CRC, independently of the indication for the examination. However, somewhat stronger associations were found for examinations with screening indications (adjusted odds ratio [OR] 0.09, 95% confidence interval [CI] 0.07-0.13) than for examinations with diagnostic indications, such as positive fecal occult blood test result (OR, 0.33; 95% CI, 0.19-0.57), surveillance after a preceding colonoscopy (OR, 0.33; 95% CI, 0.24-0.45), rectal bleeding (OR, 0.28; 95% CI, 0.20-0.40), abdominal symptoms (OR, 0.15; 95% CI, 0.10-0.21), or other (OR, 0.21; 95% CI, 0.14-0.30). Colonoscopy was also associated with a reduced risk of cancer in the right colon, regardless of the indication, although to a smaller extent than for other areas of the colon (OR for screening colonoscopy, 0.22; 95% CI, 0.14-0.33). CONCLUSIONS In a population-based case-control study, the risk of CRC was strongly reduced up to 10 years after colonoscopy for any indication. Risk was particularly low after screening colonoscopy, even for cancer in the right colon.

Telesurgical laparoscopic radical prostatectomy. Initial experience.

Introduction: Telepresence surgery offers theoretically to overcome two main problems of laparoscopic surgery, i.e. the limitation to only four degrees of freedom and the lack of stereovision. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system mainly for cardiac bypass surgery. Clinical experience in urology is still very limited. We want to present our initial experience using the device for robot–assisted laparoscopic radical prostatectomy. Material and Methods: The Intuitive surgical system consists of two main components: the surgeon’s viewing and control console with 3D imaging and the surgical arm unit that positions and maneuvers detachable surgical instruments. These instruments introduced via two 8–mm trocars allow movements in all 6 degrees of freedom due to the EndoWrist technology. The surgeon performs the procedure seated at the console holding specially designed instruments. Highly specialized computer software and mechanics transfer the surgeon’s hand movements exactly to the microsurgical movements of the manipulators at the operative site. We have used a semilunar–shaped 5–trocar arrangement with the robot’s arms at the lateral trocars and two assistant trocars medially. A sixth trocar was used in the right suprapubic area for retraction of the gland. The left assistant used different instruments such as bipolar forceps, Ultracision, Endoclip, whereas the right assistant mainly used the suctcion–irrigation device. Except the first case, the Intuitive System was attached after exposure of Retzius’ space. Results: We have treated 6 patients (2 pT2, 4 pT3, median Gleason score 6). The OR time averaged 315 (242–480) min including pelvic lymph node dissection. No intraoperative complications occurred, 1 patient required transfusions. There were no positive margins, median catheter time was 5 days. 3 patients were completely continent after 1 month. Conclusion: Telerobotic laparoscopic surgery offers several advantages over all presently available techniques, such as all six degrees of freedom, dexterity enhancement, tremor filtering, and stereovision. There is a learning curve with the device, mainly because of the magnification, the 3D image and the lack of tactile feedback. However, only after a short period of time, the experienced surgeon is able to get familiar with the device. However, there are still concerns with respect to the high investment and running costs of the device as well as regarding the necessitity of further developments of instruments for urological procedures.

Identification and Evaluation of Plasma MicroRNAs for Early Detection of Colorectal Cancer

Background Colorectal cancer (CRC) is one of the most commonly diagnosed cancers. Circulating microRNAs (miRNAs) have been suggested as potentially promising markers for early detection of CRC. We aimed to identify and evaluate a panel of miRNAs that might be suitable for CRC early detection. Methods MiRNAs were profiled by TaqMan MicroRNA Array and screened for differential expression in 5 pools of plasma samples of CRC patients (N = 50) and 5 pools of neoplasm-free controls (N = 50). Additional miRNAs were selected from a literature review. Identified candidates were evaluated in independent validation samples with respect to discrimination of CRC patients (N = 80) or advanced adenoma patients (N = 50) and neoplasm-free controls (N = 194). Diagnostic performance of the panel of miRNAs was assessed by multiple logistic regression, using bootstrap analysis to correct for over-optimism. Results Five miRNAs identified to be differentially expressed from TaqMan MicroRNA Array (miR-29a, -106b, -133a, -342-3p, -532-3p), and seven miRNAs reported to be differentially expressed in the literature (miR-18a, -20a, -21, -92a, -143, -145, -181b) were selected for validation. Nine of the twelve miRNAs (miR-18a, -20a, -21, -29a, -92a, -106b, -133a, -143, -145) were found to be differentially expressed in CRC patients and controls in the validation samples. The optimism-corrected area under the curve was 0.745 (95% confidence interval: 0.708–0.846). None of the selected miRNAs showed significant differential expression between advanced adenoma patients and neoplasm-free controls. Conclusion The identified panel of miRNAs could be of potential use in the development of a multi-marker blood based test for early detection of CRC. Impact: The study underscores the high potential of plasma miRNAs for the improvement of current offers of non-invasive CRC screening.

Laparoscopic Retroperitoneal Lymph Node Dissection for Nonseminomatous Germ Cell Tumors: Indications and Limitations

PURPOSE We describe our experience with laparoscopic retroperitoneal lymph node dissection in 26 patients with nonseminomatous germ cell tumors: 17 had stage I disease with no clinical (computerized tomography, ultrasound or tumor markers) evidence of metastases and 9 (2 with stage IIb and 7 with stage IIc disease) had residual tumor after chemotherapy but with negative tumor markers. Laparoscopic dissection was performed to assess more fully pathological status of the relevant retroperitoneal lymph nodes in both groups. MATERIALS AND METHODS The patient was positioned and trocars were introduced at sites similar to that used for transperitoneal laparoscopic nephrectomy (flank position with 3, 10 mm. and 2, 5 mm. ports). After the white line of Toldt was incised and the colon was reflected anteromedially, the retroperitoneal space was exposed. The landmarks of lymph node dissection were then isolated, including the ureter, aorta, inferior vena cava and both renal veins. Lymph node dissection was performed identical to that for open surgery, with a modified template including the paracaval, interaortocaval, upper preaortic and right common iliac nodes for right tumors, and para-aortic and upper preaortic nodes for left tumors. Lymph node chains were retrieved with a small organ bag. RESULTS The procedure was completed successfully in 16 of 17 patients with stage I disease (mean duration 268 minutes for the left and 312 minutes for the right sides). No intraoperative complications were encountered. One patient had delayed ureteral stenosis requiring operative repair, 1 had a pulmonary embolism with an uneventful outcome and 1 who underwent laparoscopic retroperitoneal lymph node dissection on the right side later had retrograde ejaculation. Embryonal carcinoma was found in 1 of the 17 patients. Average postoperative hospital stay was 4.5 days for patients without complications or conversion to an open procedure. After a median followup of 27 months no patient had regional relapse but 2 had pulmonary metastases that were treated successfully with 3 cycles of platinum based chemotherapy. Laparoscopic dissection was significantly more difficult in patients with stage II tumors after chemotherapy. Only in 2 patients with stage IIb disease was laparoscopic lymphadenectomy successful. In 5 of the 7 patients with stage IIc cancer portions of the dissection had to be done after conversion to an open (conventional) operation via a small incision (suprainguinal or pararectal). In 1 patient the laparoscopic approach was completely abandoned and converted to an open operation via a standard midline incision. In all 9 cases histopathological examination revealed complete necrosis. No patient has evidence of disease. CONCLUSIONS Our preliminary experience suggests that a modified laparoscopic retroperitoneal lymph node dissection is feasible for stage I tumors. However, it cannot be recommended after previous chemotherapy (stages IIb and IIc disease).

Multiparametric Magnetic Resonance Imaging (MRI) and MRI–Transrectal Ultrasound Fusion Biopsy for Index Tumor Detection: Correlation with Radical Prostatectomy Specimen

BACKGROUND Multiparametric magnetic resonance imaging (mpMRI) and MRI fusion targeted biopsy (FTB) detect significant prostate cancer (sPCa) more accurately than conventional biopsies alone. OBJECTIVE To evaluate the detection accuracy of mpMRI and FTB on radical prostatectomy (RP) specimen. DESIGN, SETTING AND PARTICIPANTS From a cohort of 755 men who underwent transperineal MRI and transrectal ultrasound fusion biopsy under general anesthesia between 2012 and 2014, we retrospectively analyzed 120 consecutive patients who had subsequent RP. All received saturation biopsy (SB) in addition to FTB of lesions with Prostate Imaging Reporting and Data System (PI-RADS) score ≥2. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The index lesion was defined as the lesion with extraprostatic extension, the highest Gleason score (GS), or the largest tumor volume (TV) if GS were the same, in order of priority. GS 3+3 and TV ≥1.3ml or GS ≥3+4 and TV ≥0.55ml were considered sPCa. We assessed the detection accuracy by mpMRI and different biopsy approaches and analyzed lesion agreement between mpMRI and RP specimen. RESULTS AND LIMITATIONS Overall, 120 index and 71 nonindex lesions were detected. Overall, 107 (89%) index and 51 (72%) nonindex lesions harbored sPCa. MpMRI detected 110 of 120 (92%) index lesions, FTB (two cores per lesion) alone diagnosed 96 of 120 (80%) index lesions, and SB alone diagnosed 110 of 120 (92%) index lesions. Combined SB and FTB detected 115 of 120 (96%) index foci. FTB performed significantly less accurately compared with mpMRI (p=0.02) and the combination for index lesion detection (p=0.002). Combined FTB and SB detected 97% of all sPCa lesions and was superior to mpMRI (85%), FTB (79%), and SB (88%) alone (p<0.001 each). Spearmans rank correlation coefficient for index lesion agreement between mpMRI and RP was 0.87 (p<0.001). Limitations included the retrospective design, multiple operators, and nonblinding of radiologists. CONCLUSIONS MpMRI identified 92% of index lesions compared with RP histopathology. The combination of FTB and SB was superior to both approaches alone, reliably detecting 97% of sPCa lesions. PATIENT SUMMARY Multiparametric magnetic resonance imaging detects the index lesion accurately in 9 of 10 patients; however, the combined biopsy approach, while missing less significant cancer, comes at the cost of detecting more insignificant cancer.

Bipolar transurethral resection of the prostate ‐ technical modifications and early clinical experience

The purpose of the study was to update the current modifications of transurethral resection of the prostate (TURP) using bipolar high frequency current and to report on our first own clinical experience. Based on a Medline search covering the period from January 2000 to September 2006 and our clinical experience with three different devices (VISTA‐ACMI, Gyrus, Storz), the technical basis of these modifications was described. In addition, an analysis of the actual outcome (handling, complications, morbidity) of bipolar TURP (n = 124) compared to a parallel series of monopolar TURP (N = 148) was carried out. Recently, five different modifications of bipolar resection devices (ACMI, Gyrus, Olympus, Storz, Wolf) have been introduced. Experimental and clinical data were available for four of these modifications (VISTA‐ACMI, Gyrus, Olympus, Storz). The devices differ in terms of modification of the passive electrode (two loops, single loop, resectoscope sheath). Bipolar technology allows the use of 0.9% sodium chloride (instead of glycine) as irrigant. In all bipolar devices, a slight prolongation was noted for initiation of the cut, with the VISTA showing the poorest cutting behaviour. Finest apical dissection could be performed with the Storz device. Phase III‐studies comparing bipolar and monopolar TURP showed advantages for bipolar concerning the rate of TUR‐syndrome/fluid absorption, bleeding, catheter time, whereas the resection speed was similar. In two studies using two different devices (Gyrus, Olympus) a higher rate of urethral strictures was detected. We conclude that TURP still represents the reference standard in the management of benign prostatic hyperplasia. Initial data suggest that bipolar technology is safe and effective. It may offer some advantages with respect to the reduction of TUR‐syndrome, less conductive trauma (i.e. tissue charring), cheaper irrigation solution, and a shorter catheter time. In addition to already existing phase III‐studies, larger randomized mulit‐institutional trials will have to substantiate these advantages.

Population-based prevalence estimates of history of colonoscopy or sigmoidoscopy: review and analysis of recent trends.

BACKGROUND Lower GI endoscopy, such as colonoscopy or sigmoidoscopy, is thought to have a substantial impact on colorectal cancer incidence and mortality through detection and removal of precancerous lesions and early cancers. We aimed to review prevalence estimates of history of colonoscopy or sigmoidoscopy in the general population and to analyze recent trends. METHODS A systematic review of the medical literature, including MEDLINE (1966 to August 2008) and EMBASE (1980 to August 2008), was undertaken, supplemented by searches of the European Health Interview & Health Examination Surveys database and bibliographies. Detailed age-specific and sex-specific prevalence estimates from the United States were obtained from the Behavioral Risk Factor Surveillance System surveys 2002, 2004, and 2006. RESULTS The search yielded 55 studies that met our inclusion criteria. The majority of the reports (43) originated from the United States. Other countries of origin included Australia (2), Austria (2), Canada (5), France (1), Germany (1), and Greece (1). Estimates from the United States were generally increasing over time up to 56% (2006) for lifetime use of colonoscopy or sigmoidoscopy in people aged 50 years and older. Analysis of national survey data showed higher prevalences among men aged 55 years and older than for women of the same age. Prevalences were highest for people aged 70 to 79 years. CONCLUSION Data from outside the United States were extremely limited. Prevalence estimates from the United States indicate that a considerable and increasing proportion of the population at risk has had at least 1 colonoscopy or sigmoidoscopy in their lives, although differences between age and sex groups persist. Prevalences of previous colonoscopy or sigmoidoscopy need to be taken into account in the interpretation of time trends in, and variation across, populations of colorectal cancer incidence and mortality.