1,721,022 research outputs found
Vitamin B6 and Cancer Risk: A Field Synopsis and Meta-Analysis
No full textBACKGROUND:
Vitamin B6 is involved in many biochemical reactions and might play a role in carcinogenesis. We summarized the evidence linking vitamin B6 to cancer risk.
METHODS:
We conducted a systematic review of both observational and intervention studies investigating the relationship between vitamin B6 intake or blood levels of its bioactive form pyridoxal-5'-phosphate (PLP) and the risk of any type of cancer. Random-effects meta-analysis was used to calculate pooled relative risks (RRs) and their 95% confidence intervals (CIs) across studies for high vs low categories of vitamin intake or PLP levels. We also performed a random-effects dose-response meta-analysis.
RESULTS:
We identified 121 observational studies (participants, n = 1 924 506; cases, n = 96,436) and nine randomized controlled trials (RCTs; participants, n = 34 911; cases, n = 2539) considering 19 tumor sites. High intake of dietary (food only) vitamin B6 was statistically significantly associated with lower risk of all cancers (relative risk [RR] = 0.78, 95% CI = 0.73 to 0.84) and specific tumors, with special regard to gastrointestinal carcinomas (RR = 0.68, 95% CI = 0.61 to 0.75). An inverse association was also observed between high PLP levels and the risk of all cancers (RR = 0.66, 95% CI = 0.58 to 0.76) and single tumor sites, the most consistent results being those for gastrointestinal tumors (RR = 0.56, 95% CI = 0.48 to 0.65). There was a statistically significant inverse linear relationship between cancer risk and both vitamin B6 dietary intake and PLP levels. When total (food and supplements) intake was considered, the associations were weaker or null. Findings from RCTs did not support a protective effect of vitamin B6 against cancer, although this evidence was graded as low level.
CONCLUSIONS:
Epidemiological evidence supports the potential of vitamin B6 as a cancer risk reduction agent and the role of PLP as a cancer screening biomarker, especially for gastrointestinal tumors. However, inconsistent findings from total intake and intervention studies suggest that vitamin B6 might also be an indicator of other dietary protective micronutrients
Breast Cancer Chemoprevention: A Network Meta-Analysis of Randomized Controlled Trials
No full textBackground: Several agents have been advocated for breast cancer primary prevention. However, few of them appear effective, the associated severe adverse effects limiting their uptake.
Methods: We performed a comprehensive search for randomized controlled trials (RCTs) reporting on the ability of chemoprevention agents (CPAs) to reduce the incidence of primary breast carcinoma. Using network meta-analysis, we ranked CPAs based simultaneously on efficacy and acceptability (an inverse measure of toxicity). All statistical tests were two-sided.
Results: We found 48 eligible RCTs, enrolling 271 161 women randomly assigned to receive either placebo or one of 21 CPAs. Aromatase inhibitors (anastrozole and exemestane, considered a single CPA class because of the lack of between-study heterogeneity; relative risk [RR] = 0.468, 95% confidence interval [CI] = 0.346 to 0.634), arzoxifene (RR = 0.415, 95% CI = 0.253 to 0.682), lasofoxifene (RR = 0.208, 95% CI = 0.079 to 0.544), raloxifene (RR = 0.572, 95% CI = 0.372 to 0.881), tamoxifen (RR = 0.708, 95% CI = 0.595 to 0.842), and tibolone (RR = 0.317, 95% CI = 0.127 to 0.792) were statistically significantly associated with a therapeutic effect, which was restricted to estrogen receptor-positive tumors of postmenopausal women (except for tamoxifen, which is active also during premenopause). Network meta-analysis ranking showed that the new selective estrogen receptor modulators (SERMs) arzoxifene, lasofoxifene, and raloxifene have the best benefit-risk ratio. Aromatase inhibitors and tamoxifen ranked second and third, respectively.
Conclusions: These results provide physicians and health care regulatory agencies with RCT-based evidence on efficacy and acceptability of currently available breast cancer CPAs; at the same time, we pinpoint how much work still remains to be done before pharmacological primary prevention becomes a routine option to reduce the burden of this disease
Anastomosis to stomach versus anastomosis to jejunum for reconstructing the pancreatic stump after pancreatoduodenectomy
No full textThis is the protocol for a review and there is no abstract. The objectives are as follows: To compare the performance of two types of reconstruction of the pancreatic stump (pancreatogastrostomy (PG) versus pancreaticojejunostomy (PJ)) in people undergoing pancreatoduodenectomy. © 2016 The Cochrane Collaboration
Cyto-reductive surgery combined with ipertermic itraperitoneal chemotherapy for peritoneal surface malignancies: current treatment and results.
No full textCyto-reductive Surgery (CS) combined with Hyperthermic Intra-peritoneal Chemotherapy (HIPEC) as loco-regional treatment of Peritoneal Surface Malignancies (PSM) has increasingly gained acceptance in clinical practice. This review summarizes the more relevant studies on this topic. Indications, pre-operative work-up, technical aspects, outcome and future directions of this combined approach in the treatment of Peritoneal Surface Malignancies are discussed here and proposed in an informative and didactic manner
Patterns of recurrence after resection of colorectal liver metastases: prediction by models of outcome analysis
No full textVarious series have reported similar survival and recurrence rates after resection of colorectal liver metastases (CRLM). If outcomes were predictable, indications for surgery could be improved. This hypothesis was tested in 135 consecutive patients with CRLM who underwent "curative" resection from 1977 to 1997. Among the 132 patients available for follow-up, three groups were identified on the basis of outcome: (1) survival of more than 5 years disease-free (n = 32; 24%); (2) diffuse recurrences within the first 6 months (n = 24; 18%); and (3) discrete recurrences for which reresection was performed (n = 16; 12%). As our results are similar to those reported in the literature, we assumed that about 50% of patients with resectable lesions have recognizable patterns of recurrence. At multivariate analysis, factors significant for disease-free survival (DFS) were the percentage of liver invasion, metastases to lymph nodes at the primary site, number of metastases, preoperative glutamic pyruvic transaminase (GPT) level, and type of liver resection. On the basis of the relative risk (RR) expressed by significant prognostic factors, a score model was developed, and three prognostic groups were defined: Group A, with the best prognostic score, included 23 of 32 (72%) patients who survived more than 5 years, and that with the worst prognostic score (group C) included 22 of 24 (92%) patients with early diffuse recurrences. Extreme (especially unfavorable) outcomes can therefore be predicted. By using improved models of outcome analysis, many patients could be spared surgery as first-line treatment, and stratification criteria could be worked out for future trials
Interventions for cutaneous sarcoidosis
No full textThis is a protocol for a Cochrane Review (Intervention). The objectives are as follows: To assess the clinical effectiveness of interventions for cutaneous sarcoidosis
Cytoreductive surgery combined with hyperthermic intraperitoneal intraoperative chemotherapy for peritoneal carcinomatosis arising from colon adenocarcinoma.
No full textBackground: Hyperthermic intraoperative intraperitoneal chemotherapy (HIIC) has been recently proposed to treat peritoneal carcinomatosis arising from colon adenocarcinoma, which is usually regarded as a lethal clinical entity. The purpose of this study was to evaluate the clinical outcome of this combined treatment.
Methods: A retrospective study of 46 patients treated for peritoneal carcinomatosis from colon adenocarcinoma was performed. Thirty-four patients were treated with complete cytoreductive surgery immediately followed by intraoperative HIIC with mitomycin C and cisplatin. The clinical outcome of these 34 patients was analyzed; the median follow-up period was 14.5 months.
Results: No postoperative deaths were reported. The postoperative morbidity rate was 35%. No severe locoregional or systemic toxicity was observed. The 2-year overall survival was 31%, and the median survival time and the median time to local disease progression were 18 and 13 months, respectively. Survival and local disease control in patients with well- and moderately differentiated colon adenocarcinoma were significantly better than in those with poorly differentiated tumors.
Conclusions: Considering the dismal prognosis of this condition, HIIC seems to achieve encouraging results in a selected group of patients affected with resectable peritoneal carcinomatosis arising from colon adenocarcinoma. These findings support the conduction of formal phase III randomized trials
TNFalpha-based isolated perfusion for limb-threatening soft tissue sarcomas:state of the art and future trends
No full textThe management of limb-threatening soft tissue sarcomas has not yet been standardized. Although local disease control does not affect overall survival, amputation or highly mutilating surgery may be required, which impairs the patient's quality of life. Various neoadjuvant approaches have been proposed to allow limb-sparing surgery for these locally advanced tumors. With TNFalpha-based hyperthermic isolated limb perfusion, the majority of patients can be spared amputation, with acceptable rates of locoregional and systemic complications. As yet, no other available treatment seems to give comparable results when applied to limb-threatening soft tissue sarcomas. Nevertheless, several issues remain to be addressed, such as the type and dose of drugs, repeatability of the procedure, association with radiotherapy, further indications, and evaluation of response. The authors describe the principles underlying TNFalpha-based hyperthermic isolated limb perfusion, review the worldwide experience so far published, and discuss the above issues. The potential future developments of this locoregional therapeutic approach will also be reported
Isolated limb perfusion in locally advanced cutaneous melanoma
No full textIsolated limb perfusion (ILP) is a well-established locoregional procedure to deliver high doses of cytostatics to an extremity with multiple in-transit lesions from cutaneous melanoma, with minimal systemic and mild local toxicity. This approach is quite sophisticated and requires accurate monitoring of systemic leakage and of the temperature of the affected limb in order to avoid major systemic and local side effects. Mephalan (L-PAM) is considered the reference drug, although complete responses are reported in only about 50% of patients. Since the early 1990s, tumor necrosis factor-alpha (TNF-alpha) was administered with melphalan in ILP aiming to improve the therapeutic index of this procedure. However, despite the impressive results reported, its role still remains controversial, seemingly confined to large tumor bulk. Fotemustine ILP was proposed as a less toxic alternative to L-PAM, after the results of a pilot experience claiming similar response rates with less local toxicity. A formal phase 1-2 study is now underway to confirm these findings. More straightforward procedures, such as isolated limb infusion, are appealing, as they seem capable of achieving good response rates, are easily repeatable, and are less costly. Larger series are required to validate such results. As potential agents to be delivered through ILP, new vasoactive drugs and agents with new mechanisms of action that interplay with chemotherapy, as well as virus-mediated gene therapy, are being developed
- …
