Use of ambulatory blood pressure monitoring to compare antihypertensive efficacy and safety of two angiotensin II receptor antagonists, losartan and valsartan. Losartan Trial Investigators.

The efficacy and safety of losartan and valsartan were evaluated in a multicenter, double-blind, randomized trial in patients with mild to moderate essential hypertension. Blood pressure responses to once-daily treatment with either losartan 50 mg (n = 93) or valsartan 80 mg (n = 94) for 6 weeks were assessed through measurements taken in the clinic and by 24-hour ambulatory blood pressure monitoring (ABPM). Both drugs significantly reduced clinic sitting systolic (SiSBP) and diastolic blood pressure (SiDBP) at 2, 4, and 6 weeks. Maximum reductions from baseline in SiSBP and SiDBP on 24-hour ABPM were also significant with the two treatments. The reduction in blood pressure was more consistent across patients in the losartan group, as indicated by a numerically smaller variability in change from baseline on all ABPM measures, which achieved significance at peak (P = .017) and during the day (P = .002). In addition, the numerically larger smoothness index with losartan suggested a more homogeneous antihypertensive effect throughout the 24-hour dosing interval. The antihypertensive response rate was 54% with losartan and 46% with valsartan. Three days after discontinuation of therapy, SiDBP remained below baseline in 73% of losartan and 63% of valsartan patients. Both agents were generally well tolerated. Losartan, but not valsartan, significantly decreased serum uric acid an average 0.4 mg/dL at week 6. In conclusion, once-daily losartan 50 mg and valsartan 80 mg had similar antihypertensive effects in patients with mild to moderate essential hypertension. Losartan produced a more consistent blood pressure-lowering response and significantly lowered uric acid, suggesting potentially meaningful differences between these two A II receptor antagonists.

Angiotensin II antagonists for hypertension: are there differences in efficacy?

We compared the antihypertensive efficacy of available drugs in the new angiotensin-II-antagonist (AIIA) class. The antihypertensive efficacy of losartan, valsartan, irbesartan, and candesartan was evaluated from randomized controlled trials (RCT) by performing a metaanalysis of 43 published RCT. These trials involved AIIA compared with placebo, other antihypertensive classes, and direct comparisons between AIIA. A weighted-average for diastolic and systolic blood pressure reduction with AIIA monotherapy, dose titration, and with addition of low-dose hydrochlorothiazide (HCTZ) were calculated. Weighted-average responder rates were also determined. The metaanalysis assessed a total of 11,281 patients. The absolute weighted-average reductions in diastolic (8.2 to 8.9 mm Hg) and systolic (10.4 to 11.8 mm Hg) blood pressure reductions (not placebo-corrected) for AIIA monotherapy were comparable for all AIIA. Responder rates for AIIA monotherapy were 48% to 55%. Dose titration resulted in slightly greater blood pressure reduction and an increase in responder rates to 53% to 63%. AIIA/hydrochlorothiazide combinations produced substantially greater reduction in systolic (16.1 to 20.6 mm Hg) and diastolic (9.9 to 13.6 mm Hg) blood pressure reductions than AIIA monotherapy and responder rates for AIIA/HCTZ combinations were 56% to 70%. This comprehensive analysis shows comparable antihypertensive efficacy within the AIIA class, a near-flat AIIA-dose response when titrating from starting to maximum recommended dose, and substantial potentiation of the antihypertensive effect with addition of HCTZ.

Lymph node retrieval in a randomized trial on western-type versus Japanese-type surgery in gastric cancer.

PURPOSE: In the tumor-node-metastasis (TNM) staging system, no recommendations are provided on what lymph node retrieval technique is to be used to determine lymph node status, which leads to variability in nodal status assessment and TNM staging. PATIENT AND METHODS: Lymph node retrieval was quantitated using data from 237 curatively resected gastric cancer patients, from a prospective, randomized trial that compared the Western resection with limited (D1) and the Japanese resection with extended lymphadenectomy (D2), and compared data from the literature. Moreover, the efficacy of different lymph node retrieval techniques was determined. RESULTS: The mean yield of lymph nodes was 15 in D1 and 30 in D2, which is similar to results from German investigators, but substantially lower than results from Japanese investigators (60 in D2). Use of a fat-clearance technique significantly increased (P = .01) nodal yields compared with conventional retrieval. Significantly higher yields (P < .001) were obtained by a Japanese surgeon using conventional retrieval directly postoperatively. Experience of surgicopathologic teams with processing resection specimens did not influence nodal yields. Further analysis showed that reference values for nodal yields per anatomically defined station as reported in the literature were contradicted by our results and indicated the ambiguity of such standards. CONCLUSION: Despite some anatomical variability in the distribution of lymph nodes, advice on the number of nodes to examine per N level, feasible in all patients, should be incorporated into the TNM classification to standardize nodal status assessment. Based on our findings, we advocate retrieval of nodes immediately postoperatively by the surgeon.

Lymph node staging standards in gastric cancer.

PURPOSE: In tumor-node-metastasis (TNM) staging, no recommendations are provided on the number of lymph nodes to examine per N level. We investigated the relationship between number of nodes examined and probability of detecting metastases, and ultimately staging accuracy. PATIENTS AND METHODS: Data from 473 curatively resected gastric cancer patients, from a randomized trial that compared the Western resection with limited and the Japanese resection with extended lymphadenectomy, were used. RESULTS: Yields varied between zero to 67 in N1 and zero to 43 in N2. Yields correlated significantly with classification; the more nodes examined, the more likely the classification was N+. Calculating the probability of detecting metastases using either a likelihood-ratio estimate or an exponential model, this probability increased steeply in the lower range and more gradually in the higher range yield. CONCLUSION: To standardize treatment results, we emphasize histologic examination of a fixed number of nodes per anatomically defined N level (20 in N1 and 15 in N2), corresponding with a probability to detect metastases of 60% to 65% and 40% to 45%, respectively. These yields are feasible in all resection specimens, while the extra increase in the chance of detecting metastases by examining more nodes does not compensate the effort to increase yields further. Thus, standardization of histologic TNM staging can improve and render comparison of surgical and adjuvant treatment modalities feasible.

Surgical/pathologic-stage migration confounds comparisons of gastric cancer survival rates between Japan and Western countries.

PURPOSE: Possible causes underlying the substantial differences in gastric cancer survival rates observed between Japan and the West were examined in a randomized trial comparing the Western R1 resection with limited lymphadenectomy and the Japanese R2 resection with extended lymphadenectomy. PATIENTS AND METHODS: The effect of four factors associated with lymphadenectomy on microscopic tumor-node-metastasis (TNM) staging, and on stage-specific survival rates was assessed in 473 curatively resected patients. RESULTS: After application of extended lymphadenectomy, additional information on N status was available, only in R2 resections with up-staging to N2 status in 30% of patients. The calculated effect of this stage migration on known 5-year survival rates was as follows: an increase of 1% in TNM stage Ia, 2% in Ib, 7% in II, 15% in IIIa, and 15% in IIIb. A further increase in survival was observed by stage migration to N3 or N4 status, due to selective extension of lymphadenectomy to clinically overt metastases located outside the allocated level of clearance (contamination). Incomplete lymphadenectomy of N1- or N2-level stations indicated for dissection (noncompliance) demonstrates that more migration can occur when strictly adhering to the protocol. Examining more nodes per N level (diligence) induces even more migration, since the number of nodes that were histologically examined per N level correlated significantly with nodal status (lymph node-negative [N-] or lymph node-positive [N+]). CONCLUSION: These factors explain, at least partially, superior stage-specific survival rates after R2 compared with R1 resections, without a real survival benefit in individual patients.

Evaluation of the extent of lymphadenectomy in a randomized trial of Western- versus Japanese-type surgery in gastric cancer.

PURPOSE: In the context of a prospective, randomized trial of gastric cancer treatment, comparing Western surgical resection with limited lymphadenectomy (R1) versus Japanese surgical resection with extended lymphadenectomy (R2), we analyzed adherence to the specified surgical-pathologic guidelines. PATIENTS AND METHODS: Following evaluation of 389 patients, we quantified noncompliance (ie, performance of less dissection than specified) and contamination (ie, performance of more extensive dissection than specified). Of 389 patients, pathologic data permitted identification of 237 eligible patients treated with curative intent. RESULTS: Noncompliance occurred in 84% of R1 and R2 cases, with magnitude significantly (P < .001) higher in R2 cases versus R1 cases. Contamination occurred in 48% of R1 cases and 52% of R2 cases, with the magnitude of contamination moderate and equally distributed between the two groups. The contamination in R1 resections and the noncompliance in R2 resections lead to a partial homogenization of the groups, undermining the likelihood of detecting any potential therapeutic advantage to R2 dissection. CONCLUSION: The observed tendency to perform R1 resections combined with insufficient retrieval of lymph nodes underlines the need for increased surgical-pathologic standardization in this trial. Potential remedies are discussed. Proper conduct of clinical trials requires reliable means of standardizing performance of the surgical-pathologic team, an elusive but important goal.

Adjuvant therapy after curative resection for gastric cancer: meta-analysis of randomized trials.

PURPOSE: An overview is presented of reports published since 1980, in which postoperative adjuvant chemotherapy is compared with surgery alone for patients with gastric cancer. A MEDLINE literature review yielded 123 reports, 14 of which were relevant randomized trials; data from 11 of these trials were (or became) available for analysis of crude mortality odds. These 11 trials included 2,096 patients. METHODS: Odds ratios were calculated by comparing the adjuvant treatment arm with the observation-only arm. Those odds ratios that could be considered homogeneous yielded an estimated common odds ratio of 0.88 (95% confidence interval [CI], 0.78 to 1.08), which was slightly, but far from significantly, in support of adjuvant treatment. RESULTS: The results confirm the common opinion that the adjuvant chemotherapy regimens prescribed in these trials, although effective in phase II studies, do not improve survival. Furthermore they indicate that postoperative chemotherapy in general offers no additional survival benefit for patients with curatively resected gastric cancer. CONCLUSION: In conclusion, at present, postoperative chemotherapy cannot be considered as standard adjuvant treatment. New trials of adjuvant therapy for gastric cancer must include a no-treatment control arm.