Intravesical sequential gemcitabine and docetaxel versus bacillus calmette-guerin (BCG) plus interferon in patients with recurrent non-muscle invasive bladder cancer following a single induction course of BCG

INTRODUCTION

Repeat BCG induction remains an option for select non-muscle invasive bladder cancer (NMIBC) patients who fail initial therapy. Alternative salvage intravesical regimens such as Gemcitabine and Docetaxel (Gem/Doce) have been investigated. We aimed to compare the efficacy BCG plus interferon a-2b (BCG/IFN) and Gem/Doce in patients with recurrent NMIBC after a single prior BCG course.

METHODS

The National Phase II BCG/IFN trial database and multi-institutional Gem/Doce database were queried for patients with recurrent NMIBC after one prior BCG induction course, excluding those with BCG unresponsive disease. Stabilized inverse probability treatment weighted survival curves were estimated using the Kaplan-Meier method and compared. Propensity scores were derived from a logistic regression model. The primary outcome was recurrence free survival (RFS); secondary outcomes were high-grade (HG) RFS and risk factors for treatment failure.

RESULTS

We identified 197 BCG/IFN and 93 Gem/Doce patients who met study criteria. Patients receiving Gem/Doce were older and more likely to have HG disease, CIS, and persistent disease following induction BCG (all P < 0.01). After propensity score-based weighting, the adjusted 1- and 2-year RFS was 61% and 53% after BCG/IFN versus 68% and 46% after Gem/Doce (P = 0.95). Adjusted 1- and 2-year HG-RFS was 60% and 51% after BCG/IFN versus 63% and 42% after Gem/Doce (P = 0.68). Multivariable Cox regression revealed that Gem/Doce treatment was not associated with an increased risk of failure (HR = 0.97, P = 0.89) as compared to BCG/IFN.

CONCLUSION

Patients with recurrent NMIBC after a single induction BCG failure and not deemed BCG unresponsive had similar oncologic outcomes with Gem/Doce and BCG/IFN in a post-hoc analysis. Additional prospective studies are needed.

Multi-Institution Evaluation of Sequential Gemcitabine and Docetaxel as Rescue Therapy for Nonmuscle Invasive Bladder Cancer

PURPOSE

Rescue intravesical therapies for patients with bacillus Calmette-Guérin failure nonmuscle invasive bladder cancer remain a critical focus of ongoing research. Sequential intravesical gemcitabine and docetaxel therapy has shown safety and efficacy in 2 retrospective, single institution cohorts. This doublet has since been adopted as an intravesical salvage option at multiple institutions. We report the results of a multi-institutional evaluation of gemcitabine and docetaxel.

MATERIALS AND METHODS

Each institution retrospectively reviewed all records of patients treated with intravesical gemcitabine and docetaxel for nonmuscle invasive bladder cancer between June 2009 and May 2018. Only patients with recurrent nonmuscle invasive bladder cancer and a history of bacillus Calmette-Guérin treatment were included in the analysis. If patients were disease-free after induction, maintenance was instituted at the treating physician's discretion. Posttreatment surveillance followed American Urological Association guidelines. Survival analysis was performed using the Kaplan-Meier method and risk factors for treatment failure were assessed with Cox regression models.

RESULTS

Overall 276 patients (median age 73 years, median followup 22.9 months) received treatment. Nine patients were unable to tolerate a full induction course. One and 2-year recurrence-free survival rates were 60% and 46%, and high grade recurrence-free survival rates were 65% and 52%, respectively. Ten patients (3.6%) had disease progression on transurethral resection. Forty-three patients (15.6%) went on to cystectomy (median 11.3 months from induction), of whom 11 (4.0%) had progression to muscle invasion. Analysis identified no patient, disease or prior treatment related factors associated with gemcitabine and docetaxel failure.

CONCLUSIONS

Intravesical gemcitabine and docetaxel therapy is well tolerated and effective, providing a durable response in patients with recurrent nonmuscle invasive bladder cancer after bacillus Calmette-Guérin therapy. Further prospective study is warranted.

Expectant long-term follow-up of patients with chronic urinary retention

AIMS

To describe urologic complications in patients with chronically elevated post-void residual (PVR) volumes and to evaluate other related risk factors during a long-term follow-up in patients managed conservatively.

METHODS

Non-neurogenic patients who refused surgical intervention of the prostate and had PVR volumes >300 mL on two or more separate occasions at least 6 months apart were included. We followed this cohort over time, recorded complications and evaluated risk factors for complications.

RESULTS

Twenty-eight men with a mean age of 74 were followed for a median of 56 months (IQR: 26-101 months); 26 had benign prostatic hyperplasia with a median prostate size of 55 cc. Baseline median PVR was 468 cc (IQR: 395-828) and follow-up median PVR was 508 cc (IQR: 322-714). During follow-up, 13 patients (46%) had at least one complication with acute urinary retention being the most common occurring in 10 patients (36%) with 15 episodes. Other complications presented in less than 15%, and no patients developed permanent renal insufficiency. Patients with prostate size ≥ 100 cc had significantly higher total number of acute retention episodes (P-value: 0.01).

CONCLUSIONS

Although the presence of CUR could commonly predispose to episodes of acute retention, severe complications are infrequent although present. Additionally, prostate size may play a role in increasing some adverse outcomes. With proper counseling about different complications, patients with retention who denied surgical treatment can be safely followed for at least 5 years without renal deterioration.

Gleason Misclassification Rate Is Independent of Number of Biopsy Cores in Systematic Biopsy

OBJECTIVE

To compare the utility of saturation core biopsy and 12-core biopsy in detecting true Gleason grades, using final pathology in prostatectomy specimens as outcome measures, with a particular interest in Gleason upgrading.

PATIENTS AND METHODS

We compared the concordance rates of Gleason grades diagnosed on biopsies and prostatectomy specimens in 375 consecutive patients, including 106 saturation biopsies (18-33 cores, median = 20 cores) and 269 12-core biopsies. Grading bias was addressed by a central rereview of all cases that had discordance in reporting high Gleason grades (Gleason grade ≥ 4) on biopsies and prostatectomy specimens.

RESULTS

For patients with high Gleason grades on final pathology, saturation and 12-core biopsy schemes had a comparable sensitivity, specificity, negative and positive predictive values (72.5% vs 69.5%, 91.9% vs 97.6%, 64.2% vs 58.4%, and 94.3% vs 98.5%, respectively) in detecting high Gleason grades. On multivariate analysis, prebiopsy serum prostate-specific antigen and clinical T stage independently predicted Gleason upgrading; saturation biopsy was not a significant predictor. Approximately one-third of cases where high Gleason grade was not present in the biopsy were attributed to the confinement of high-grade tumors to unusual anatomic locations such as anterior lobes, apex, bladder neck, and parasagittal zones.

CONCLUSION

Our study showed that Gleason misclassification rate is independent of the number of biopsy cores in systematic biopsy. One of the reasons for missing high Gleason grade tumors on systematic biopsy was unusual tumor location outside of the biopsy grid, supporting the need for improved detection technique such as magnetic resonance imaging-guided targeted biopsies.

Low free testosterone levels predict disease reclassification in men with prostate cancer undergoing active surveillance

OBJECTIVE

To determine whether total testosterone and free testosterone levels predict disease reclassification in a cohort of men with prostate cancer (PCa) on active surveillance (AS).

PATIENTS AND METHODS

Total testosterone and free testosterone concentrations were determined at the time the men began the AS protocol. Statistical analysis was performed using Student's t-test and a chi-squared test to compare groups. Odds ratios (ORs) with 95% confidence intervals (CIs) were obtained using univariate logistic regression. Receiver-operator characteristic curves were generated to determine the investigated testosterone thresholds. Kaplan-Meier curves were used to estimate time to disease reclassification. A Cox proportional hazard regression model was used for multivariate analysis.

RESULTS

A total of 154 men were included in the AS cohort, of whom 54 (35%) progressed to active treatment. Men who had disease reclassification had significantly lower free testosterone levels than those who were not reclassified (0.75 vs 1.02 ng/dL, P = 0.03). Men with free testosterone levels <0.45 ng/dL had a higher rate of disease reclassification than patients with free testosterone levels ≥0.45 (P = 0.032). Free testosterone levels <0.45 ng/dL were associated with a several-fold increase in the risk of disease reclassification (OR 4.3, 95% CI 1.25-14.73). Multivariate analysis showed that free testosterone and family history of PCa were independent predictors of disease reclassification.

CONCLUSIONS

Free testosterone levels were lower in men with PCa who had reclassification during AS. Men with moderately severe reductions in free testosterone level are at increased risk of disease reclassification.

Diagnosis of relevant prostate cancer using supplementary cores from magnetic resonance imaging-prompted areas following multiple failed biopsies

OBJECTIVES

To establish the value of MRI in targeting re-biopsy for undiagnosed prostate cancer despite multiple negative biopsies and determine clinical relevance of detected tumors.

MATERIALS AND METHODS

Thirty-eight patients who underwent MRI after 2 or more negative biopsies due to continued clinical suspicion and later underwent TRUS-guided biopsy supplemented by biopsy of suspicious areas depicted by MRI were identified. Diagnostic performance of endorectal 3T MRI in diagnosing missed cancer foci was assessed using biopsy results as the standard of reference. Ratio of positive biopsies using systematic versus MRI-prompted approaches was compared. Gleason scores of detected cancers were used as surrogate for clinical relevance.

RESULTS

Thirty-four percent of patients who underwent MRI before re-biopsy had prostate cancer on subsequent biopsy. The positive biopsy yield with systematic sampling was 23% versus 92% with MRI-prompted biopsies(p<0.0001). Seventy-seven percent of tumors were detected exclusively in the MRI-prompted zones. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of MRI to provide a positive biopsy were 92%, 60%, 55%, 94% and 71%, respectively. The anterior gland and apical regions contained most tumors; 75% of cancers detected by MRI-prompted biopsy had Gleason score≥7.

CONCLUSIONS

Clinically relevant tumors missed by multiple TRUS-guided biopsies can be detected by a MRI-prompted approach.

Comparing costs of robotic, laparoscopic, and open partial nephrectomy

Abstract Background and Purpose: Laparoscopic and robot-assisted partial nephrectomy (LPN and RPN) are common minimally invasive alternatives to open partial nephrectomy (OPN) for management of renal tumors. Cost discrepancies of these approaches warrants evaluation. We compared hospital costs associated with RPN, LPN, and OPN.

PATIENTS AND METHODS

Costs were captured for 25 patients in each group who underwent RPN, LPN, or OPN at our institution between November 2008 and September 2010. Variable costs included operating room (OR) time, supplies, anesthesia, and inpatient care costs. Fixed costs included equipment purchase and maintenance. Impact of variable and fixed costs were estimated using sensitivity analysis.

RESULTS

Overall variable costs were similar for RPN, LPN, and OPN ($6375 vs $6075 vs $5774, P=0.117, respectively). OR supplies contributed a greater cost for RPN and LPN than OPN ($2179 vs $1987 vs $181, P<0.0001, respectively), while inpatient stay costs were higher for OPN compared with LPN and RPN ($2418 vs $1305 vs $1274, P<0.0001, respectively). Sensitivity analysis of variable costs demonstrates that RPN and LPN can represent less costly alternatives to OPN if hospital stay for RPN and LPN is ≤2 days and OR time <195 and 224 minutes, respectively. Inclusion of fixed costs made OPN less expensive than LPN and RPN unless use of the robot increases and operative times are reduced.

CONCLUSION

By minimizing OR time and hospital stay, RPN and LPN can be cost equivalent to OPN regarding variable costs. When including fixed costs, RPN and LPN were more costly than OPN, but equivalence may be possible with improvements in efficiency.

Cost comparison of robotic, laparoscopic, and open partial nephrectomy

394

Background: Laparoscopic and robotic partial nephrectomy (LPN and RPN) are increasingly common minimally invasive alternatives to open partial nephrectomy (OPN) for management of renal tumors. The cost discrepancies of these approaches warrants evaluation. We compared hospital costs associated with RPN, LPN, and OPN.

Methods: Variable hospital costs including operating room (OR) time, supplies, anesthesia, inpatient care, radiology, pharmacy, and laboratory charges were captured for 25 patients who underwent OPN, LPN, and RPN at our institution between 11/2008 -9/2010. Fixed costs of acquisition of a laparoscopic suite and a robotic system (including maintenance) were amortized over 7 years. We considered alternative scenarios through one-way and multi-way sensitivity analysis.

Results: We found similar overall variable costs for OPN, LPN, and RPN. Sensitivity analysis demonstrated that RPN and LPN are more cost effective than OPN (excluding fixed costs) if the average hospital stay is < 2 days, or OR time less is than 204 and 196 mins, respectively. By including fixed costs of equipment, RPN and LPN are always more costly than OPN.

Conclusions: There was no difference among variable hospital costs of OPN, LPN, and RPN. Minimizing OR time and hospital stay reduces RPN and LPN costs to levels comparable to OPN. Inclusion of fixed costs makes LPN and RPN more expensive than OPN, but increased utilization and efficiency can decrease cost per case.

[Table: see text]

Expanded prostate cancer index composite for clinical practice: development and validation of a practical health related quality of life instrument for use in the routine clinical care of patients with prostate cancer

PURPOSE

Measuring the health related quality of life of patients with prostate cancer in routine clinical practice is hindered by the lack of instruments enabling efficient, real-time, point of care scoring of multiple health related quality of life domains. Thus, we developed an instrument for this purpose.

MATERIALS AND METHODS

The Expanded Prostate Cancer Index Composite for Clinical Practice is a 1-page, 16-item questionnaire that we constructed to measure urinary incontinence, urinary irritation, and the bowel, sexual and hormonal health related quality of life domains. We eliminated conceptually overlapping items from the 3-page Expanded Prostate Cancer Index Composite-26 and revised the questionnaire format to mirror the AUA symptom index, thereby enabling practitioners to calculate health related quality of life scores at the point of care. We administered the Expanded Prostate Cancer Index Composite for Clinical Practice to a new cohort of patients with prostate cancer in community based and academic oncology, radiation, and urology practices to evaluate instrument validity as well as ease of use in clinical practice.

RESULTS

A total of 175 treated and 132 untreated subjects with prostate cancer completed the Expanded Prostate Cancer Index Composite for Clinical Practice. The domain scores of the Expanded Prostate Cancer Index Composite for Clinical Practice correlated highly with the respective domain scores from longer versions of the Expanded Prostate Cancer Index Composite (r≥0.93 for all domains). The Expanded Prostate Cancer Index Composite for Clinical Practice showed high internal consistency (Cronbach's α 0.64-0.84) and sensitivity to prostate cancer treatment related effects (p<0.05 in each of 5 health related quality of life domains). Patients completed the Expanded Prostate Cancer Index Composite for Clinical Practice efficiently (96% in less than 10 minutes and with 11% missing items). It was deemed very convenient by clinicians in 87% of routine clinical encounters and clinicians accurately scored completed questionnaires 94% of the time.

CONCLUSIONS

The Expanded Prostate Cancer Index Composite for Clinical Practice is a valid instrument that enables patient reported, health related quality of life to be measured efficiently and accurately at the point of care, and thereby facilitates improved emphasis and management of patient reported outcomes.

Risk stratification and validation of prostate specific antigen density as independent predictor of progression in men with low risk prostate cancer during active surveillance

PURPOSE

We assessed risk stratification in patients with low grade prostate cancer managed by active surveillance using a 20-core saturation biopsy technique.

MATERIALS AND METHODS

A total of 135 consecutive patients with low risk prostate cancer were prospectively entered in an active surveillance program in a 10-year period. The study entrance requirement and progression definition followed Epstein criteria using only pathological parameters, ie fewer than 3 positive cores, Gleason score 6 or less and 50% or less of any single core involved. All patients were monitored by restaging 20-core saturation biopsy every 12 to 18 months. A total of 120 patients with at least 1 rebiopsy form the basis of this report.

RESULTS

Of the cohort 30% progressed during a median of 2.4 years. Three multivariate analyses were performed. The first analysis used variables only at diagnosis biopsy and revealed that prostate specific antigen density greater than 0.08 ng/ml/cc and prostate cancer family history were significant predictors of progression. When combined in a 3-level risk factor score, they were significant (p = 0.003). The second multivariate analysis considered changes in characteristics between diagnosis biopsy and first rebiopsy. Prostate specific antigen velocity along with prostate specific antigen density and family history highly predicted progression according to a 4-level risk factor score (p <0.0001). The third multivariate analysis validated the previously reported prostate specific antigen density cutoff of 0.08 ng/ml/cc at first rebiopsy as a significant predictor of subsequent progression (HR 3.16, 95% CI 1.12, 8.93; p = 0.03).

CONCLUSIONS

Risk factor stratification can be used to significantly predict the outcome in patients on active surveillance. Prostate specific antigen density 0.08 ng/ml/cc at first rebiopsy was validated as a significant predictor of subsequent progression.

Lower limits of detection using magnetic resonance imaging for solid components in cystic renal neoplasms

OBJECTIVES

We determined the positive predictive value (PPV) for malignancy in complex renal cysts with focal nodular enhancement seen on magnetic resonance imaging (MRI).

METHODS

A surgical database was reviewed to identify all patients having both a preoperative 3 dimensional (3D) renal MRI and a radical or partial nephrectomy from January 2000 through April 2004 at our hospital. A group of 21 patients were identified with focal nodular enhancement within cystic renal masses. Pathologic correlation was made in each case.

RESULTS

We performed 286 nephrectomies during the study period. Of these patients, 159 (56%) had a preoperative MRI studies. There were 21 of 159 (13%) patients with complex cystic lesions that displayed focal nodular enhancement, 14 of which (67%) measured 10 mm or larger in size. Twenty (95%) of the 21 lesions were renal cell carcinoma. The single, benign lesion was a cystic nephroma. Fuhrman grade 1 or grade 2 cancers were found in the majority of patients (80%), and there were no grade 4 cancers. Fifteen patients had a preoperative computerized tomography (CT) scan as well and nodular enhancement was suspected in only 4 patients (27%). MRI findings upgraded these lesions in 11 patients (73%).

CONCLUSIONS

The demonstration of solid enhancing nodular components with high-resolution 3D MRI provides excellent positive predictive value for diagnosing neoplastic cystic renal lesions, including a large percentage 10 mm or larger in size. Our experience suggests a 95% likelihood that cystic renal lesions with focal nodular enhancement are malignant. We recommend that such lesions be considered malignant.

c-Fos as a proapoptotic agent in TRAIL-induced apoptosis in prostate cancer cells

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/Apo-2L promotes apoptosis in cancer cells while sparing normal cells. Although many cancers are sensitive to TRAIL-induced apoptosis, some evade the proapoptotic effects of TRAIL. Therefore, differentiating molecular mechanisms that distinguish between TRAIL-sensitive and TRAIL-resistant tumors are essential for effective cancer therapies. Here, we show that c-Fos functions as a proapoptotic agent by repressing the antiapoptotic molecule c-FLIP(L). c-Fos binds the c-FLIP(L) promoter, represses its transcriptional activity, and reduces c-FLIP(L) mRNA and protein levels. Therefore, c-Fos is a key regulator of c-FLIP(L), and activation of c-Fos determines whether a cancer cell will undergo cell death after TRAIL treatment. Strategies to activate c-Fos or inhibit c-FLIP(L) may potentiate TRAIL-based proapoptotic therapies.

MR classification of renal masses with pathologic correlation

To perform a feature analysis of malignant renal tumors evaluated with magnetic resonance (MR) imaging and to investigate the correlation between MR imaging features and histopathological findings. MR examinations in 79 malignant renal masses were retrospectively evaluated, and a feature analysis was performed. Each renal mass was assigned to one of eight categories from a proposed MRI classification system. The sensitivity and specificity of the MRI classification system to predict the histologic subtype and nuclear grade was calculated. Subvoxel fat on chemical shift imaging correlated to clear cell type (p < 0.05); sensitivity = 42%, specificity = 100%. Large size, intratumoral necrosis, retroperitoneal vascular collaterals, and renal vein thrombosis predicted high-grade clear cell type (p < 0.05). Small size, peripheral location, low intratumoral SI on T2-weighted images, and low-level enhancement were associated with low-grade papillary carcinomas (p < 0.05). The sensitivity and specificity of the MRI classification system for diagnosing low grade clear cell, high-grade clear cell, all clear cell, all papillary, and transitional carcinomas were 50% and 94%, 93% and 75%, 92% and 83%, 80% and 94%, and 100% and 99%, respectively. The MRI feature analysis and proposed classification system help predict the histological type and nuclear grade of renal masses.

Spaced education improves the retention of clinical knowledge by medical students: a randomised controlled trial

PURPOSE

Medical knowledge learned by trainees is often quickly forgotten. How can the educational process be tailored to shift learning into longer-term memory? We investigated whether 'spaced education', consisting of weekly e-mailed case scenarios and clinical questions, could improve the retention of students' learning.

METHODS

During the 2004-5 surgery clerkships, 3rd-year students completed a mandatory 1-week clinical rotation in urology and validated web-based teaching programme on 4 core urology topics. Spaced educational e-mails were constructed on all 4 topics based on a validated urology curriculum. Each consisted of a short clinically relevant question or clinical case scenario in multiple-choice question format, followed by the answer, teaching point summary and explanations of the answers. Students were randomised to receive weekly e-mailed case scenarios in only 2 of the 4 urology topics upon completion of their urology rotation. Students completed a validated 28-item test (Cronbach's alpha = 0.76) on all 4 topics prior to and after the rotation and at the end of the academic year.

RESULTS

A total of 95 of 133 students (71%) completed the end-of-year test. There were no significant differences in baseline characteristics between randomised cohorts. Spaced education significantly improved composite end-of-year test scores (P < 0.001, paired t-test). The impact of the spaced educational e-mails was largest for those students who completed their urology education 6-8 and 9-11 months previously (Cohen's effect sizes of 1.01 and 0.73, respectively).

CONCLUSION

Spaced education consisting of clinical scenarios and questions distributed weekly via e-mail can significantly improve students' retention of medical knowledge.

The TRA-1-60 and TRA-1-81 human pluripotent stem cell markers are expressed on podocalyxin in embryonal carcinoma

We have previously identified the cell adhesion protein podocalyxin expressed in a human pluripotent stem cell, embryonal carcinoma (EC), which is a malignant germ cell. Podocalyxin is a heavily glycosylated membrane protein with amino acid sequence homology to the hematopoietic stem cell marker CD34. Since the initial discovery of podocalyxin in a cancerous stem cell, numerous new studies have identified podocalyxin in many different human cancers and in embryonic stem cells lines (ES) derived from human embryos. Embryonal carcinoma, as do all human pluripotent stem cells, expresses TRA-1-60 and TRA-1-81 antigens, and although their molecular identities are unknown, they are commonly used as markers of undifferentiated pluripotent human stem cells. We report here that purified podocalyxin from embryonal carcinoma has binding activity with the TRA-1-60 and TRA-1-81 antibodies. Embryonal carcinoma cells treated with retinoic acid undergo differentiation and lose the TRA-1-60/TRA-1-81 markers from their plasma membrane surface. We show that podocalyxin is modified in the retinoic acid-treated cells and has an apparent molecular mass of 170 kDa on protein blots as compared with the apparent 200-kDa molecular weight form of podocalyxin expressed in untreated cells. Furthermore, the modified form of podocalyxin no longer reacts with the TRA-1-60/TRA-1-81 antibodies. Thus, embryonal carcinoma expresses two distinct forms of podocalyxin, and the larger version is a molecular carrier of the human stem cell-defining antigens TRA-1-60 and TRA-1-81.

A multi-institutional randomized controlled trial of adjuvant Web-based teaching to medical students

PURPOSE

To investigate the impact of an adjuvant Web-based teaching program on medical students' learning during clinical rotations.

METHOD

From April 2003 to May 2004, 351 students completing clinical rotations in surgery-urology at four U.S. medical schools were invited to volunteer for the study. Web-based teaching cases were developed covering four core urologic topics. Students were block randomized to receive Web-based teaching on two of the four topics. Before and after a designated duration at each institution (ranging one to three weeks), students completed a validated 28-item Web-based test (Cronbach's alpha = .76) covering all four topics. The test was also administered to a subset of students at one school at the conclusion of their third-year to measure long-term learning.

RESULTS

Eighty-one percent of all eligible students (286/351) volunteered to participate in the study, 73% of whom (210/286) completed the Web-based program. Compared to controls, Web-based teaching significantly increased test scores in the four topics at each medical school (p < .001, mixed analysis of variance), corresponding to a Cohen's d effect size of 1.52 (95% confidence interval [CI], 1.23-1.80). Learning efficiency was increased three-fold by Web-based teaching (Cohen's d effect size 1.16; 95% CI 1.13-1.19). Students who were tested a median of 4.8 months later demonstrated significantly higher scores for Web-based teaching compared to non-Web-based teaching (p = .007, paired t-test). Limited learning was noted in the absence of Web-based teaching.

CONCLUSIONS

This randomized controlled trial provides Class I evidence that Web-based teaching as an adjunct to clinical experiences can significantly and durably improve medical students' learning.