Compressão pneumática intermitente na prevenção de trombose venosa profunda em pacientes cirúrgicos: revisão sistemática e metanálise

Introdução: Trombose Venosa Profunda (TVP) é o resultado de inúmeros fatores, incluindo estase venosa, injuria endotelial e hipercoagulação do sangue. O embolismo pulmonar é a maior complicação da TVP e ocorre quando um trombo ou um coágulo sangüíneo desloca-se em direção aos pulmões. O tromboembolismo é um sério problema de saúde e é responsável por um considerável número de mortes súbitas e por significantes custos de hospitalizações em todo o mundo. Entre os métodos profiláticos usados na prevenção da TVP, há os classificados como mecânicos e os farmacológicos. Ambos são efetivos e podem ser usados sempre que necessário, tendo sido recomendados por consenso internacional. Objetivos: Avaliar a incidência da TVP em pacientes cirúrgicos através da Compressão pneumática Intermitente CPI (coxa/perna ou perna/pé) contra nenhuma forma de profilaxia ou contra fármacos. Métodos: Revisão sistemática de ensaios clínicos randomizados, utilizando a metodologia Cochrane, através de buscas eletrônica e manual. Foram incluídos pacientes cirúrgicos, de ambos os sexos, cuja intervenção foi o uso de aparelhos de compressão pneumática intermitente. Resultados: 4269 pacientes cirúrgicos investigados por 31 ensaios submetidos a um número de intervenções cirúrgicas, incluindo cirurgia ortopédica (joelho e quadris), geral, ginecológica, urológica e neurológica. Dados combinados demonstraram efeitos de tratamento virtualmente iguais entre CPI e abordagens farmacológicas [0.95 (95%CI 0.82, 1.10)], em relação à incidência de TVP. Entretanto, o risco de hemorragia foi maior e estatisticamente significante em pacientes tratados com intervenções farmacológicas [0.37(95%CI 0.20, 0.69)]. Conclusão: Comparações entre as estratégias farmacológicas e mecânicas indicam que ambas são similares na prevenção de trombose venosa profunda. Entretantio, a evidência atual suportaria a escolha das abordagens mecâncias, uma vez que o risco de eventos hemorrágicos favorece os métodos mecânicos.

Combined modality treatment improves tumor control and overall survival in patients with early stage Hodgkin's lymphoma: a systematic review

Combined modality treatment (CMT) of chemotherapy followed by localized radiotherapy is standard treatment for patients with early stage Hodgkin's lymphoma. However, the role of radiotherapy has been questioned recently and some clinical study groups advocate chemotherapy only for this indication. We thus performed a systematic review with meta-analysis of randomized controlled trials comparing chemotherapy alone with CMT in patients with early stage Hodgkin's lymphoma with respect to response rate, tumor control and overall survival (OS). We searched Medline, EMBASE and the Cochrane Library as well as conference proceedings from January 1980 to February 2009 for randomized controlled trials comparing chemotherapy alone versus the same chemotherapy regimen plus radiotherapy. Progression free survival and similar outcomes were analyzed together as tumor control. Effect measures used were hazard ratios for OS and tumor control as well as relative risks for complete response (CR). Meta-analyses were performed using RevMan5. Five randomized controlled trials involving 1,245 patients were included. The hazard ratio (HR) was 0.41 (95% confidence interval (CI) 0.25 to 0.66) for tumor control and 0.40 (95% CI 0.27 to 0.59) for OS for patients receiving CMT compared to chemotherapy alone. CR rates were similar between treatment groups. In sensitivity analyses another 6 trials were included that did not fulfill the inclusion criteria of our protocol but were considered relevant to the topic. These trials underlined the results of the main analysis. In conclusion, adding radiotherapy to chemotherapy improves tumor control and OS in patients with early stage Hodgkin's lymphoma.

Hand and ultrasonic instrumentation for orthograde root canal treatment of permanent teeth

Root canal treatment is a frequently performed dental procedure and is carried out on teeth in which irreversible pulpitis has led to necrosis of the dental pulp. Removal of the necrotic tissue remnants and cleaning and shaping of the root canal are important phases of root canal treatment. Treatment options include the use of hand and rotary instruments and methods using ultrasonic or sonic equipment. OBJECTIVES: The objectives of this systematic review of randomized controlled trials were to determine the relative clinical effectiveness of hand instrumentation versus ultrasonic instrumentation alone or in conjunction with hand instrumentation for orthograde root canal treatment of permanent teeth. MATERIAL AND METHODS: The search strategy retrieved 226 references from the Cochrane Oral Health Group Trials Register (7), the Cochrane Central Register of Controlled Trials (CENTRAL) (12), MEDLINE (192), EMBASE (8) and LILACS (7). No language restriction was applied. The last electronic search was conducted on December 13th, 2007. Screening of eligible studies was conducted in duplicate and independently. RESULTS: Results were to be expressed as fixed-effect or random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. No eligible randomized controlled trials were identified. CONCLUSIONS: This review illustrates the current lack of published or ongoing randomized controlled trials and the unavailability of high-level evidence based on clinically relevant outcomes referring to the effectiveness of ultrasonic instrumentation used alone or as an adjunct to hand instrumentation for orthograde root canal treatment. In the absence of reliable research-based evidence, clinicians should base their decisions on clinical experience, individual circumstances and in conjunction with patients' preferences where appropriate. Future randomized controlled trials might focus more closely on evaluating the effectiveness of combinations of these interventions with an emphasis on not only clinically relevant, but also patient-centered outcomes.

Orthodontic therapy and gingival recession: a systematic review

To perform a systematic review on the effect of changes in incisor inclination owing to orthodontic treatment and the occurrence of gingival recession. PubMed, EMBASE Excerpta Medica and CENTRAL of the Cochrane Library were searched and a hand search was performed. From 1925 articles identified, 17 articles were finally included: six experimental animal studies and 11 retrospective clinical studies in humans. More proclined teeth compared with less proclined teeth or untreated teeth had in most studies a higher occurrence or severity of gingival recession. Contradictory results were found regarding a possible statistically significant correlation between the extent of gingival recession and the amount of incisor proclination during treatment, width of attached gingiva, hygiene, periodontal condition or thickness of the symphysis. There are no high quality animal or clinical studies on this topic. Movement of the incisors out of the osseous envelope of the alveolar process may be associated with a higher tendency for developing gingival recessions. The amount of recession found in studies with statistically significant differences between proclined and non-proclined incisors is small and the clinical consequence questionable. Because of the low level of evidence of the included studies, the results should be considered with caution. Further randomized clinical studies including clinical examination of hygiene and gingival condition before, during and after treatment are needed to clarify the effect of orthodontic changes in incisor inclination and the occurrence of gingival recession.

Body mass index, hormone replacement therapy, and endometrial cancer risk: a meta-analysis

Background: Body mass index (BMI) is a risk factor for endometrial cancer. We quantified the risk and investigated whether the association differed by use of hormone replacement therapy (HRT), menopausal status, and histologic type. Methods: We searched MEDLINE and EMBASE (1966 to December 2009) to identify prospective studies of BMI and incident endometrial cancer. We did random-effects meta-analyses, meta-regressions, and generalized least square regressions for trend estimations assuming linear, and piecewise linear, relationships. Results: Twenty-four studies (17,710 cases) were analyzed; 9 studies contributed to analyses by HRT, menopausal status, or histologic type, all published since 2003. In the linear model, the overall risk ratio (RR) per 5 kg/m2 increase in BMI was 1.60 (95% CI, 1.52–1.68), P < 0.0001. In the piecewise model, RRs compared with a normal BMI were 1.22 (1.19–1.24), 2.09 (1.94–2.26), 4.36 (3.75–5.10), and 9.11 (7.26–11.51) for BMIs of 27, 32, 37, and 42 kg/m2, respectively. The association was stronger in never HRT users than in ever users: RRs were 1.90 (1.57–2.31) and 1.18 (95% CI, 1.06–1.31) with P for interaction ¼ 0.003. In the piecewise model, the RR in never users was 20.70 (8.28–51.84) at BMI 42 kg/m2, compared with never users at normal BMI. The association was not affected by menopausal status (P ¼ 0.34) or histologic type (P ¼ 0.26). Conclusions: HRT use modifies the BMI-endometrial cancer risk association. Impact: These findings support the hypothesis that hyperestrogenia is an important mechanism underlying the BMI-endometrial cancer association, whilst the presence of residual risk in HRT users points to the role of additional systems. Cancer Epidemiol Biomarkers Prev; 19(12); 3119–30.

Joint lavage for osteoarthritis of the knee

Background Osteoarthritis is the most common form of joint disorder and a leading cause of pain and physical disability. Observational studies suggested a benefit for joint lavage, but recent, sham-controlled trials yielded conflicting results, suggesting joint lavage not to be effective. Objectives To compare joint lavage with sham intervention, placebo or non-intervention control in terms of effects on pain, function and safety outcomes in patients with knee osteoarthritis. Search methods We searched CENTRAL, MEDLINE, EMBASE, and CINAHL up to 3 August 2009, checked conference proceedings, reference lists, and contacted authors. Selection criteria We included studies if they were randomised or quasi-randomised trials that compared arthroscopic and non-arthroscopic joint lavage with a control intervention in patients with osteoarthritis of the knee. We did not apply any language restrictions. Data collection and analysis Two independent review authors extracted data using standardised forms. We contacted investigators to obtain missing outcome information. We calculated standardised mean differences (SMDs) for pain and function, and risk ratios for safety outcomes. We combined trials using inverse-variance random-effects meta-analysis. Main results We included seven trials with 567 patients. Three trials examined arthroscopic joint lavage, two non-arthroscopic joint lavage and two tidal irrigation. The methodological quality and the quality of reporting was poor and we identified a moderate to large degree of heterogeneity among the trials (I2 = 65%). We found little evidence for a benefit of joint lavage in terms of pain relief at three months (SMD -0.11, 95% CI -0.42 to 0.21), corresponding to a difference in pain scores between joint lavage and control of 0.3 cm on a 10-cm visual analogue scale (VAS). Results for improvement in function at three months were similar (SMD -0.10, 95% CI -0.30 to 0.11), corresponding to a difference in function scores between joint lavage and control of 0.2 cm on a WOMAC disability sub-scale from 0 to 10. For pain, estimates of effect sizes varied to some degree depending on the type of lavage, but this variation was likely to be explained by differences in the credibility of control interventions: trials using sham interventions to closely mimic the process of joint lavage showed a null-effect. Reporting on adverse events and drop out rates was unsatisfactory, and we were unable to draw conclusions for these secondary outcomes. Authors' conclusions Joint lavage does not result in a relevant benefit for patients with knee osteoarthritis in terms of pain relief or improvement of function.

Sacral neuromodulation for neurogenic lower urinary tract dysfunction: systematic review and meta-analysis

Context Treatment of neurogenic lower urinary tract dysfunction (LUTD) is a challenge, because conventional therapies often fail. Sacral neuromodulation (SNM) has become a well-established therapy for refractory non-neurogenic LUTD, but its value in patients with a neurologic cause is unclear. Objective To assess the efficacy and safety of SNM for neurogenic LUTD. Evidence acquisition Studies were identified by electronic search of PubMed, EMBASE, and ScienceDirect (on 15 April 2010) and hand search of reference lists and review articles. SNM articles were included if they reported on efficacy and/or safety of tested and/or permanently implanted patients suffering from neurogenic LUTD. Two reviewers independently selected studies and extracted data. Study estimates were pooled using Bayesian random-effects meta-analysis. Evidence synthesis Of the 26 independent studies (357 patients) included, the evidence level ranged from 2b to 4 according to the Oxford Centre for Evidence-Based Medicine. Half (n = 13) of the included studies reported data on both test phase and permanent SNM; the remaining studies were confined to test phase (n = 4) or permanent SNM (n = 9). The pooled success rate was 68% for the test phase (95% credibility interval [CrI], 50–87) and 92% (95% CrI, 81–98%) for permanent SNM, with a mean follow-up of 26 mo. The pooled adverse event rate was 0% (95% CrI, 0–2%) for the test phase and 24% (95% CrI, 6–48%) for permanent SNM. Conclusions There is evidence indicating that SNM may be effective and safe for the treatment of patients with neurogenic LUTD. However, the number of investigated patients is low with high between-study heterogeneity, and there is a lack of randomised, controlled trials. Thus, well-designed, adequately powered studies are urgently needed before more widespread use of SNM for neurogenic LUTD can be recommended.

Measurement issues in trials of pediatric acute diarrheal diseases: a systematic review

BACKGROUND: Worldwide, diarrheal diseases rank second among conditions that afflict children. Despite the disease burden, there is limited consensus on how to define and measure pediatric acute diarrhea in trials. OBJECTIVES: In RCTs of children involving acute diarrhea as the primary outcome, we documented (1) how acute diarrhea and its resolution were defined, (2) all primary outcomes, (3) the psychometric properties of instruments used to measure acute diarrhea and (4) the methodologic quality of included trials, as reported. METHODS: We searched CENTRAL, Embase, Global Health, and Medline from inception to February 2009. English-language RCTs of children younger than 19 years that measured acute diarrhea as a primary outcome were chosen. RESULTS: We identified 138 RCTs reporting on 1 or more primary outcomes related to pediatric acute diarrhea/diseases. Included trials used 64 unique definitions of diarrhea, 69 unique definitions of diarrhea resolution, and 46 unique primary outcomes. The majority of included trials evaluated short-term clinical disease activity (incidence and duration of diarrhea), laboratory outcomes, or a composite of these end points. Thirty-two trials used instruments (eg, single and multidomain scoring systems) to support assessment of disease activity. Of these, 3 trials stated that their instrument was valid; however, none of the trials (or their citations) reported evidence of this validity. The overall methodologic quality of included trials was good. CONCLUSIONS: Even in what would be considered methodologically sound clinical trials, definitions of diarrhea, primary outcomes, and instruments employed in RCTs of pediatric acute diarrhea are heterogeneous, lack evidence of validity, and focus on indices that may not be important to participants.

Should intentional endovascular stent-graft coverage of the left subclavian artery be preceded by prophylactic revascularisation?

Thoracic endovascular aortic repair (TEVAR) has emerged as a promising therapeutic alternative to conventional open aortic replacement but it requires suitable proximal and distal landing zones for stent-graft anchoring. Many aortic pathologies affect in the immediate proximity of the left subclavian artery (LSA) limiting the proximal landing zone site without proximal vessel coverage. In patients in whom the distance between the LSA and aortic lesion is too short, extension of the landing zone can be obtained by covering the LSA's origin with the endovascular stent graft (ESG). This manoeuvre has the potential for immediate and delayed neurological and vascular symptoms. Some authors, therefore, propose prophylactic revascularisation of the LSA by transposition or bypass, while others suggest prophylactic revascularisation only under certain conditions, and still others see no requirement for prophylactic revascularisation in anticipation of LSA ostium coverage. In this review about LSA revascularisation in TEVAR patients with coverage of the LSA, we searched the electronic databases MEDLINE and EMBASE historically until the end date of May 2010 with the search terms left subclavian artery, covering, endovascular, revascularisation and thoracic aorta. We have gathered the most complete scientific evidence available used to support the various concepts to deal with this issue. After a review of the current available literature, 23 relevant articles were found, where we have identified and analysed three basic treatment concepts for LSA revascularisation in TEVAR patients (prophylactic, conditional prophylactic and no prophylactic LSA revascularisation). The available evidence supports prophylactic revascularisation of the LSA before ESG LSA coverage when preoperative imaging reveals abnormal supra-aortic vascular anatomy or pathology. We further conclude that elective patients undergoing planned coverage of the LSA during TEVAR should receive prophylactic LSA transposition or LSA-to-left-common-carotid-artery (LCCA) bypass surgery to prevent severe neurological complications, such as paraplegia or brain stem infarction.

A review of the cost effectiveness of bisphosphonates in the treatment of post-menopausal osteoporosis in Switzerland

The economic burden associated with osteoporosis is considerable. As such, cost-effectiveness analyses are important contributors to the diagnostic and therapeutic decision-making process. The aim of this study was to review the cost effectiveness of treating post-menopausal osteoporosis with bisphosphonates and identify the key factors that influence the cost effectiveness of such treatment in the Swiss setting. A systematic search of databases (MEDLINE, EMBASE and the Cochrane Library) was conducted to identify published literature on the cost effectiveness of bisphosphonates in post-menopausal osteoporosis in the Swiss setting. Outcomes were compared with similar studies in Western European countries. Three cost-effectiveness studies of bisphosphonates in this patient population were identified; all were from a healthcare payer perspective. Outcomes showed that, relative to no treatment, treatment with oral bisphosphonates was predicted to be cost saving for most women aged ≥70 years with osteoporosis or at least one risk factor for fracture, and cost effective for women aged ≥75 years without prior fracture when used as a component of a population-based screen-and-treat programme. Results were most sensitive to changes in fracture risk, cost of fractures, cost of treatment, nursing home admissions and adherence with treatment. Swiss results were generally comparable to those in other European settings. Assuming similar clinical efficacy, lowering treatment cost (through the use of price-reduced brand-name or generic drugs) and/or improving adherence should both contribute to further improving the cost effectiveness of bisphosphonates in women with post-menopausal osteoporosis. Published evidence indicates that bisphosphonates are estimated to be similarly cost effective or cost saving in most treatment scenarios of post-menopausal osteoporosis in Switzerland and in neighbouring European countries.

Chemotherapy alone versus chemotherapy plus radiotherapy for early stage Hodgkin lymphoma

Background Combined modality treatment (CMT) consisting of chemotherapy followed by localised radiotherapy is standard treatment for patients with early stage Hodgkin lymphoma (HL). However, due to long term adverse effects such as secondary malignancies, the role of radiotherapy has been questioned recently and some clinical study groups advocate chemotherapy only for this indication. Objectives We performed a systematic review with meta-analysis of randomised controlled trials (RCTs) comparing chemotherapy alone with CMT in patients with early stage Hodgkin lymphoma with respect to response rate, progression-free survival (alternatively tumour control) and overall survival (OS). Search methods We searched MEDLINE, EMBASE and CENTRAL as well as conference proceedings from January 1980 to November 2010 for randomised controlled trials comparing chemotherapy alone to the same chemotherapy regimen plus radiotherapy. Selection criteria Randomised controlled trials comparing chemotherapy alone with CMT in patients with early stage HL. Trials in which the chemotherapy differed between treatment arms were excluded. Trials with more than 20% of patients in advanced stage were also excluded. Data collection and analysis Effect measures used were hazard ratios (HR) for tumour control and OS as well as relative risks for response rates. Two review authors independently extracted data and assessed quality of trials. We contacted study authors to obtain missing information. Since none of the trials reported progression-free survival according to our definitions, all similar outcomes were evaluated as tumour control. Main results Five RCTs involving 1245 patients were included. The HR was 0.41 (95% confidence interval (CI) 0.25 to 0.66) for tumour control and 0.40 (95% CI 0.27 to 0.61) for OS for patients receiving CMT compared to chemotherapy alone. Complete response rates were similar between treatment groups. In sensitivity analyses another six trials were included that did not fulfil the inclusion criteria of our protocol but were considered relevant to the topic. These trials underlined the results of the main analysis. Authors' conclusions Adding radiotherapy to chemotherapy improves tumour control and overall survival in patients with early stage Hodgkin lymphoma.

Domains of physical activity and all-cause mortality: systematic review and dose-response meta-analysis of cohort studies

Background The dose–response relation between physical activity and all-cause mortality is not well defined at present. We conducted a systematic review and meta-analysis to determine the association with all-cause mortality of different domains of physical activity and of defined increases in physical activity and energy expenditure. Methods MEDLINE, Embase and the Cochrane Library were searched up to September 2010 for cohort studies examining all-cause mortality across different domains and levels of physical activity in adult general populations. We estimated combined risk ratios (RRs) associated with defined increments and recommended levels, using random-effects meta-analysis and dose–response meta-regression models. Results Data from 80 studies with 1 338 143 participants (118 121 deaths) were included. Combined RRs comparing highest with lowest activity levels were 0.65 [95% confidence interval (95% CI) 0.60–0.71] for total activity, 0.74 (95% CI 0.70–0.77) for leisure activity, 0.64 (95% CI 0.55–0.75) for activities of daily living and 0.83 (95% CI 0.71–0.97) for occupational activity. RRs per 1-h increment per week were 0.91 (95% CI 0.87–0.94) for vigorous exercise and 0.96 (95% CI 0.93–0.98) for moderate-intensity activities of daily living. RRs corresponding to 150 and 300 min/week of moderate to vigorous activity were 0.86 (95% CI 0.80–0.92) and 0.74 (95% CI 0.65–0.85), respectively. Mortality reductions were more pronounced in women. Conclusion Higher levels of total and domain-specific physical activity were associated with reduced all-cause mortality. Risk reduction per unit of time increase was largest for vigorous exercise. Moderate-intensity activities of daily living were to a lesser extent beneficial in reducing mortality.

Role of hepatitis C virus genotype 3 in liver fibrosis progression - a systematic review and meta-analysis

The progression of liver fibrosis in chronic hepatitis C has long been considered to be independent from viral genotypes. However, recent studies suggest an association between Hepatitis C virus (HCV) genotype 3 and accelerated liver disease progression. We completed a systematic review and meta-analysis of studies evaluating the association between HCV genotypes and fibrosis progression. PubMed, Embase and ISI Web of Knowledge databases were searched for cohort, cross-sectional and case-control studies on treatment-naïve HCV-infected adults in which liver fibrosis progression rate (FPR) was assessed by the ratio of fibrosis stage in one single biopsy to the duration of infection (single-biopsy studies) or from the change in fibrosis stage between two biopsies (paired biopsies studies). A random effect model was used to derive FPR among different HCV genotypes. Eight single-biopsy studies (3182 patients, mean/median duration of infection ranging from 9 to 21 years) and eight paired biopsies studies (mean interval between biopsies 2-12 years) met the selection criteria. The odds ratio for the association of genotype 3 with accelerated fibrosis progression was 1.52 (95% CI 1.12-2.07, P = 0.007) in single-biopsy studies and 1.37 (95% CI 0.87-2.17, P = 0.17) in paired biopsy studies. In conclusion, viral genotype 3 was associated with faster fibrosis progression in single-biopsy studies. This observation may have important consequences on the clinical management of genotype 3-infected patients. The association was not significant in paired biopsies studies, although the latter may be limited by important indication bias, short observation time and small sample size.

Meta-analysis and dose-response metaregression: circulating insulin-like growth factor I (IGF-I) and mortality

Context: IGF-I plays a central role in metabolism and growth regulation. High IGF-I levels are associated with increased cancer risk and low IGF-I levels with increased risk for cardiovascular disease. Objective: Our objective was to determine the relationship between circulating IGF-I levels and mortality in the general population using random-effects meta-analysis and dose-response metaregression. Data Sources: We searched PubMed, EMBASE, Web of Science, and Cochrane Library from 1985 to September 2010 to identify relevant studies. Study Selection: Population-based cohort studies and (nested) case-control studies reporting on the relation between circulating IGF-I and mortality were assessed for eligibility. Data Extraction: Data extraction was performed by two investigators independently, using a standardized data extraction sheet. Data Synthesis: Twelve studies, with 14,906 participants, were included. Overall, risk of bias was limited. Mortality in subjects with low or high IGF-I levels was compared with mid-centile reference categories. All-cause mortality was increased in subjects with low as well as high IGF-I, with a hazard ratio (HR) of 1.27 (95% CI = 1.08–1.49) and HR of 1.18 (95% CI = 1.04–1.34), respectively. Dose-response metaregression showed a U-shaped relation of IGF-I and all-cause mortality (P = 0.003). The predicted HR for the increase in mortality comparing the 10th IGF-I with the 50th percentile was 1.56 (95% CI = 1.31–1.86); the predicted HR comparing the 90th with the 50th percentile was 1.29 (95% CI = 1.06–1.58). A U-shaped relationship was present for both cancer mortality and cardiovascular mortality. Conclusions: Both low and high IGF-I concentrations are associated with increased mortality in the general population.

Thymic peptides for treatment of cancer patients

Background Purified thymus extracts (pTE) and synthetic thymic peptides (sTP) are thought to enhance the immune system of cancer patients in order to fight the growth of tumour cells and to resist infections due to immunosuppression induced by the disease and antineoplastic therapy. Objectives To evaluate the effectiveness of pTE and sTP for the management of cancer. Search methods We searched CENTRAL (The Cochrane Library 2010, Issue 3), MEDLINE, EMBASE, AMED, BIOETHICSLINE, BIOSIS, CATLINE, CISCOM, HEALTHSTAR, HTA, SOMED and LILACS (to February 2010). Selection criteria Randomised trials of pTE or sTP in addition to chemotherapy or radiotherapy, or both, compared to the same regimen with placebo or no additional treatment in adult cancer patients. Data collection and analysis Two authors independently extracted data from published trials. We derived odds ratios (OR) from overall survival (OS) and disease-free survival (DFS) rates, tumour response (TR) rates, and rates of adverse effects (AE) related to antineoplastic treatments. We used a random-effects model for meta-analysis. Main results We identified 26 trials (2736 patients). Twenty trials investigated pTE (thymostimulin or thymosin fraction 5) and six trials investigated sTP (thymopentin or thymosin α1). Twenty-one trials reported results for OS, six for DFS, 14 for TR, nine for AE and 10 for safety of pTE and sTP. Addition of pTE conferred no benefit on OS (RR 1.00, 95% CI 0.79 to 1.25); DFS (RR 0.97, 95% CI 0.82 to 1.16); or TR (RR 1.07, 95% CI 0.92 to 1.25). Heterogeneity was moderate to high for all these outcomes. For thymosin α1 the pooled RR for OS was 1.21 (95% CI 0.94 to 1.56, P = 0.14), with low heterogeneity; and 3.37 (95% CI 0.66 to 17.30, P = 0.15) for DFS, with moderate heterogeneity. The pTE reduced the risk of severe infectious complications (RR 0.54, 95% CI 0.38 to 0.78, P = 0.0008; I² = 0%). The RR for severe neutropenia in patients treated with thymostimulin was 0.55 (95% CI 0.25 to 1.23, P = 0.15). Tolerability of pTE and sTP was good. Most of the trials had at least a moderate risk of bias. Authors' conclusions Overall, we found neither evidence that the addition of pTE to antineoplastic treatment reduced the risk of death or disease progression nor that it improved the rate of tumour responses to antineoplastic treatment. For thymosin α1, there was a trend for a reduced risk of dying and of improved DFS. There was preliminary evidence that pTE lowered the risk of severe infectious complications in patients undergoing chemotherapy or radiotherapy.