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BMC Urology Jun 2019Conflicting evidence exists regarding the effect of hypertension on the prognosis of metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Conflicting evidence exists regarding the effect of hypertension on the prognosis of metastatic renal cell carcinoma (mRCC) patients treated with tyrosine kinase inhibitors (TKIs). This study aimed to assess the predictive value of TKIs-induced hypertension in patients with mRCC.
METHODS
This study was registered in PROSPERO (CRD42019129593). PubMed, Embase, Web of Science and the Cochrane Library database were searched with terms: "renal cell carcinoma", "hypertension", "blood pressure", "tyrosine kinase inhibitor", "sunitinib", "axitinib", "sorafenib" and "pazopanib" until March 21, 2019. Hazard Ratios (HR) and 95% confidence intervals (CI) for progression-free survival (PFS) or overall survival (OS) were extracted and analyzed with Stata 15.0 software. Heterogeneity was assessed using the I value. Meta-regression, subgroup analysis and sensitivity analysis were also performed to explore heterogeneity. Publication bias was assessed with funnel plots and precisely assessed by Egger's and Begg's tests. The quality of evidence of outcomes was generated according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE).
RESULTS
A total of 4661 patients from 22 studies were included in the study. The results showed that the increase of blood pressure was an effective predictor for longer PFS (HR = 0.59, 95% CI: 0.48-0.71, p < 0.001; I = 77.3%) and OS (HR = 0.57, 95% CI: 0.45-0.70, p < 0.001; I = 77.4%) of patients with mRCC. Subgroup analysis revealed that patients receiving sunitinib and pazopanib could have longer PFS and OS.
CONCLUSIONS
This study indicated that TKIs-induced hypertension may be a good predictor for better prognosis of patients with mRCC receiving TKIs treatment, especially using sunitinib or pazopanib.
Topics: Carcinoma, Renal Cell; Disease-Free Survival; Humans; Hypertension; Kidney Neoplasms; Prognosis; Protein Kinase Inhibitors; Survival Rate
PubMed: 31174518
DOI: 10.1186/s12894-019-0481-5 -
PloS One 2019In the absence of clinical trials providing direct efficacy results, this study compares different methods of indirect treatment comparison (ITC), and their respective... (Comparative Study)
Comparative Study Meta-Analysis
BACKGROUND
In the absence of clinical trials providing direct efficacy results, this study compares different methods of indirect treatment comparison (ITC), and their respective impacts on efficacy estimates for lenvatinib (LEN) plus everolimus (EVE) combination therapy compared to other second-line treatments for advanced/metastatic renal cell carcinoma (a/mRCC).
METHODS
Using EVE alone as the common comparator, the Bucher method for ITC compared LEN + EVE with cabozantinib (CAB), nivolumab (NIV), placebo (PBO) and axitinib (AXI). Hazard ratios (HR) for overall survival (OS) and progression-free survival (PFS) estimated the impact of applying three versions of the LEN+EVE trial data in separate ITCs. Last, to overcome exchangeability bias and potential violations to the proportional hazards assumption, a network meta-analysis using fractional polynomials was performed.
RESULTS
Bucher ITCs demonstrated LEN + EVE superiority over EVE for PFS, indirect superiority to NIV, AXI, and PBO, and no difference to CAB. For OS, LEN + EVE was superior to EVE and indirectly superior to PBO, applying original HOPE 205 data. Using European Medicines Agency data, LEN + EVE was directly superior to EVE for OS. Fractional polynomial HRs for PFS and OS substantially overlapped with Bucher estimates, demonstrating LEN+EVE superiority over EVE, alone, NIV, and CAB. However, there were no statistically significant results as the credible intervals for HR crossed 1.0.
CONCLUSIONS
Comparing three Bucher ITCs, LEN + EVE demonstrated superior PFS when indirectly compared to NIV, AXI, and PBO, and mixed results for OS. While fractional polynomial modelling for PFS and OS failed to find statistically significant differences in LEN + EVE efficacy, the overall HR trends were comparable.
Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Renal Cell; Everolimus; Humans; Kidney Neoplasms; Neoplasm Staging; Phenylurea Compounds; Quinolines; Treatment Outcome
PubMed: 30835737
DOI: 10.1371/journal.pone.0212899 -
BMJ Open Mar 2019To compare the effectiveness and safety of treatments for advanced or metastatic renal cell carcinoma (amRCC) after treatment with vascular endothelial growth factor...
OBJECTIVE
To compare the effectiveness and safety of treatments for advanced or metastatic renal cell carcinoma (amRCC) after treatment with vascular endothelial growth factor (VEGF)-targeted treatment.
DESIGN
Systematic review and network meta-analysis of randomised controlled trials (RCTs) and comparative observational studies. MEDLINE, EMBASE and Cochrane Library were searched up to January 2018.
PARTICIPANTS
People with amRCC requiring treatment after VEGF-targeted treatment.
INTERVENTIONS
Axitinib, cabozantinib, everolimus, lenvatinib with everolimus, nivolumab, sorafenib and best supportive care (BSC).
OUTCOMES
Primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes were objective response rate (ORR), adverse events, and health-related quality of life (HRQoL).
RESULTS
Twelve studies were included (n=5144): five RCTs and seven observational studies. Lenvatinib with everolimus significantly increased OS and PFS over everolimus (HR 0.61, 95% Credible Interval [95%CrI]: 0.36 to 0.96 and 0.47, 95%CrI: 0.26 to 0.77, respectively) as did cabozantinib (HR 0.66, 95%CrI: 0.53 to 0.82 and 0.51, 95%CrI: 0.41 to 0.63, respectively). This remained the case when observational evidence was included. Nivolumab also significantly improved OS versus everolimus (HR 0.74, 95%CrI: 0.57 to 0.93). OS sensitivity analysis, including observational studies, indicates everolimus being more effective than axitinib and sorafenib. However, inconsistency was identified in the OS sensitivity analysis. PFS sensitivity analysis suggests axitinib is more effective than everolimus, which may be more effective than sorafenib. The results for ORR supported the OS and PFS analyses. Nivolumab is associated with fewer grade 3 or grade 4 adverse events than lenvatinib with everolimus or cabozantinib. HRQoL could not be analysed due to differences in tools used.
CONCLUSIONS
Lenvatinib with everolimus, cabozantinib and nivolumab are effective in prolonging the survival for people with amRCC subsequent to VEGF-targeted treatment, but there is considerable uncertainty about how they compare to each other and how much better they are than axitinib and sorafenib.
PROSPERO REGISTRATION NUMBER
CRD42017071540.
Topics: Aged; Antineoplastic Agents; Carcinoma, Renal Cell; Female; Humans; Kidney Neoplasms; Male; Middle Aged; Molecular Targeted Therapy; Network Meta-Analysis; Observational Studies as Topic; Progression-Free Survival; Quality of Life; Randomized Controlled Trials as Topic
PubMed: 30826762
DOI: 10.1136/bmjopen-2018-024691 -
Health Technology Assessment... Jan 2018Several therapies have recently been approved for use in the NHS for pretreated advanced or metastatic renal cell carcinoma (amRCC), but there is a lack of comparative... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Several therapies have recently been approved for use in the NHS for pretreated advanced or metastatic renal cell carcinoma (amRCC), but there is a lack of comparative evidence to guide decisions between them.
OBJECTIVE
To evaluate the clinical effectiveness and cost-effectiveness of axitinib (Inlyta, Pfizer Inc., NY, USA), cabozantinib (Cabometyx, Ipsen, Slough, UK), everolimus (Afinitor, Novartis, Basel, Switzerland), nivolumab (Opdivo, Bristol-Myers Squibb, NY, USA), sunitinib (Sutent, Pfizer, Inc., NY, USA) and best supportive care (BSC) for people with amRCC who were previously treated with vascular endothelial growth factor (VEGF)-targeted therapy.
DATA SOURCES
A systematic review and mixed-treatment comparison (MTC) of randomised controlled trials (RCTs) and non-RCTs. Primary outcomes were overall survival (OS) and progression-free survival (PFS). Secondary outcomes were objective response rates (ORRs), adverse events (AEs) and health-related quality of life (HRQoL). MEDLINE, EMBASE and The Cochrane Library were searched from inception to January and June 2016 for RCTs and non-RCTs, respectively. Two reviewers abstracted data and performed critical appraisals.
REVIEW METHODS
A fixed-effects MTC was conducted for OS, PFS [hazard ratios (HRs)] and ORR (odds ratios), and all were presented with 95% credible intervals (CrIs). The RCT data formed the primary analyses, with non-RCTs and studies rated as being at a high risk of bias included in sensitivity analyses (SAs). HRQoL and AE data were summarised narratively. A partitioned survival model with health states for pre progression, post progression and death was developed to perform a cost-utility analysis. Survival curves were fitted to the PFS and OS results from the MTC. A systematic review of HRQoL was undertaken to identify sources of health state utility values.
RESULTS
Four RCTs ( = 2618) and eight non-RCTs ( = 1526) were included. The results show that cabozantinib has longer PFS than everolimus (HR 0.51, 95% CrI 0.41 to 0.63) and both treatments are better than BSC. Both cabozantinib (HR 0.66, 95% CrI 0.53 to 0.82) and nivolumab (HR 0.73, 95% CrI 0.60 to 0.89) have longer OS than everolimus. SAs were consistent with the primary analyses. The economic analysis, using drug list prices, shows that everolimus may be more cost-effective than BSC with an incremental cost-effectiveness ratio (ICER) of £45,000 per quality-adjusted life-year (QALY), as it is likely to be considered an end-of-life treatment. Cabozantinib has an ICER of £126,000 per QALY compared with everolimus and is unlikely to be cost-effective. Nivolumab was dominated by cabozantinib (i.e. more costly and less effective) and axitinib was dominated by everolimus.
LIMITATIONS
Treatment comparisons were limited by the small number of RCTs. However, the key limitation of the analysis is the absence of the drug prices paid by the NHS, which was a limitation that could not be avoided owing to the confidentiality of discounts given to the NHS.
CONCLUSIONS
The RCT evidence suggests that cabozantinib is likely to be the most effective for PFS and OS, closely followed by nivolumab. All treatments appear to delay disease progression and prolong survival compared with BSC, although the results are heterogeneous. The economic analysis shows that at list price everolimus could be recommended as the other drugs are much more expensive with insufficient incremental benefit. The applicability of these findings to the NHS is somewhat limited because existing confidential patient access schemes could not be used in the analysis. Future work using the discounted prices at which these drugs are provided to the NHS would better inform estimates of their relative cost-effectiveness.
STUDY REGISTRATION
This study is registered as PROSPERO CRD42016042384.
FUNDING
The National Institute for Health Research Health Technology Assessment programme.
Topics: Anilides; Antineoplastic Agents; Axitinib; Carcinoma, Renal Cell; Clinical Trials as Topic; Cost-Benefit Analysis; Everolimus; Humans; Kidney Neoplasms; Models, Econometric; Nivolumab; Pyridines; Quality-Adjusted Life Years; Sunitinib; Technology Assessment, Biomedical; Vascular Endothelial Growth Factor A
PubMed: 29393024
DOI: 10.3310/hta22060 -
International Braz J Urol : Official... 2018We conducted a systematic review and meta-analysis of the literature on the efficacy of the targeted therapies in the treatment of advanced RCC and, via an indirect... (Meta-Analysis)
Meta-Analysis Review
We conducted a systematic review and meta-analysis of the literature on the efficacy of the targeted therapies in the treatment of advanced RCC and, via an indirect comparison, to provide an optimal treatment among these agents. A systematic search of Medline, Scopus, Cochrane Library and Clinical Trials unpublished was performed up to Jan 1, 2015 to identify eligible randomized trials. Outcomes of interest assessing a targeted agent included progression free survival (PFS), overall survival (OS) and objective response rate (ORR). Thirty eligible randomized controlled studies, total twentyfourth trails (5110 cases and 4626 controls) were identified. Compared with placebo and IFN-α, single vascular epithelial growth factor (receptor) tyrosine kinase inhibitor and mammalian target of rapamycin agent (VEGF(r)-TKI & mTOR inhibitor) were associated with improved PFS, improved OS and higher ORR, respectively. Comparing sorafenib combination vs sorafenib, there was no significant difference with regard to PFS and OS, but with a higher ORR. Comparing single or combination VEGF(r)-TKI & mTOR inhibitor vs BEV + IFN-α, there was no significant difference with regard to PFS, OS, or ORR. Our network ITC meta-analysis also indicated a superior PFS of axitinib and everolimus compared to sorafenib. Our data suggest that targeted therapy with VEGF(r)-TKI & mTOR inhibitor is associated with superior efficacy for treating advanced RCC with improved PFS, OS and higher ORR compared to placebo and IFN-α. In summary, here we give a comprehensive overview of current targeted therapies of advanced RCC that may provide evidence for the adequate targeted therapy selecting.
Topics: Carcinoma, Renal Cell; Disease-Free Survival; ErbB Receptors; Humans; Kidney Neoplasms; Molecular Targeted Therapy; Randomized Controlled Trials as Topic; Receptors, Vascular Endothelial Growth Factor; Vascular Endothelial Growth Factor A
PubMed: 29211397
DOI: 10.1590/S1677-5538.IBJU.2017.0315 -
The Cochrane Database of Systematic... May 2017Partial nephrectomy and radical nephrectomy are the relevant surgical therapy options for localised renal cell carcinoma. However, debate regarding the effects of these... (Review)
Review
BACKGROUND
Partial nephrectomy and radical nephrectomy are the relevant surgical therapy options for localised renal cell carcinoma. However, debate regarding the effects of these surgical approaches continues and it is important to identify and summarise high-quality studies to make surgical treatment recommendations.
OBJECTIVES
To assess the effects of partial nephrectomy compared with radical nephrectomy for clinically localised renal cell carcinoma.
SEARCH METHODS
We searched CENTRAL, MEDLINE, PubMed, Embase, Web of Science, BIOSIS, LILACS, Scopus, two trial registries and abstracts from three major conferences to 24 February 2017, together with reference lists; and contacted selected experts in the field.
SELECTION CRITERIA
We included a randomised controlled trial comparing partial and radical nephrectomy for participants with small renal masses.
DATA COLLECTION AND ANALYSIS
One review author screened all of the titles and abstracts; only citations that were clearly irrelevant were excluded at this stage. Next, two review authors independently assessed full-text reports, identified relevant studies, evaluated the eligibility of the studies for inclusion, assessed trial quality and extracted data. The update of the literature search was performed by two independent review authors. We used Review Manager 5 for data synthesis and data analyses.
MAIN RESULTS
We identified one randomised controlled trial including 541 participants that compared partial nephrectomy to radical nephrectomy. The median follow-up was 9.3 years.Based on low quality evidence, we found that time-to-death of any cause was decreased using partial nephrectomy (HR 1.50, 95% CI 1.03 to 2.18). This corresponds to 79 more deaths (5 more to 173 more) per 1000. Also based on low quality evidence, we found no difference in serious adverse events (RR 2.04, 95% CI 0.19 to 22.34). Findings are consistent with 4 more surgery-related deaths (3 fewer to 78 more) per 1000.Based on low quality evidence, we found no difference in time-to-recurrence (HR 1.37, 95% CI 0.58 to 3.24). This corresponds to 12 more recurrences (14 fewer to 70 more) per 1000. Due to the nature of reporting, we were unable to analyse overall rates for immediate and long-term adverse events. We found no evidence on haemodialysis or quality of life.Reasons for downgrading related to study limitations (lack of blinding, cross-over), imprecision and indirectness (a substantial proportion of patients were ultimately found not to have a malignant tumour). Based on the finding of a single trial, we were unable to conduct any subgroup or sensitivity analyses.
AUTHORS' CONCLUSIONS
Partial nephrectomy may be associated with a decreased time-to-death of any cause. With regards to surgery-related mortality, cancer-specific survival and time-to-recurrence, partial nephrectomy appears to result in little to no difference.
Topics: Carcinoma, Renal Cell; Cause of Death; Humans; Kidney Neoplasms; Neoplasm Recurrence, Local; Nephrectomy; Randomized Controlled Trials as Topic; Time Factors
PubMed: 28485814
DOI: 10.1002/14651858.CD012045.pub2 -
Cancer Research and Treatment Oct 2017Despite advancements in therapy for advanced gastric and gastroesophageal junction cancers, their prognosis remains dismal. Tumor angiogenesis plays a key role in cancer... (Review)
Review
Despite advancements in therapy for advanced gastric and gastroesophageal junction cancers, their prognosis remains dismal. Tumor angiogenesis plays a key role in cancer growth and metastasis, and recent studies indicate that pharmacologic blockade of angiogenesis is a promising approach to therapy. In this systematic review, we summarize current literature on the clinical benefit of anti-angiogenic agents in advanced gastric cancer. We conducted a systematic search of PubMed and conference proceedings including the American Society of Clinical Oncology, the European Society for Medical Oncology, and the European Cancer Congress. Included studies aimed to prospectively evaluate the efficacy and safety of anti-angiogenic agents in advanced gastric or gastroesophageal junction cancer. Each trial investigated at least one of the following endpoints: overall survival, progression-free survival/time to progression, and/or objective response rate. Our search yielded 139 publications. Forty-two met the predefined inclusion criteria. Included studies reported outcomes with apatinib, axitinib, bevacizumab, orantinib, pazopanib, ramucirumab, regorafenib, sorafenib, sunitinib, telatinib, and vandetanib. Second-line therapy with ramucirumab and third-line therapy with apatinib are the only anti-angiogenic agents so far shown to significantly improve survival of patients with advanced gastric cancer. Overall, agents that specifically target the vascular endothelial growth factor ligand or receptor have better safety profile compared to multi-target tyrosine kinase inhibitors.
Topics: Angiogenesis Inhibitors; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Biomarkers; Clinical Trials as Topic; Esophageal Neoplasms; Esophagogastric Junction; Humans; Molecular Targeted Therapy; Neoplasm Staging; Protein Kinase Inhibitors; Quality of Life; Receptor, ErbB-2; Stomach Neoplasms; Treatment Outcome; Vascular Endothelial Growth Factor A
PubMed: 28052652
DOI: 10.4143/crt.2016.176 -
OncoTargets and Therapy 2016This study was performed to evaluate the comparative efficacy and safety of axitinib and sorafenib in the therapy of metastatic renal cell carcinoma. (Review)
Review
OBJECTIVE
This study was performed to evaluate the comparative efficacy and safety of axitinib and sorafenib in the therapy of metastatic renal cell carcinoma.
MATERIALS AND METHODS
Eligible studies were searched from PubMed, Embase, and Future Medicine databases. The pooled hazard ratios and relative risk ratios (RRs) were calculated by using Stata 12.0 software.
RESULTS
A total of 1,011 patients qualified to participate in this Phase III study that included randomized controlled trials. Meta-analysis results showed that axitinib was more highly and significantly associated with a survival benefit in the independently assessed progression-free survival in comparison to sorafenib. The values of RR of the objective response rate and disease control rate were also significantly different. Results of the analysis of adverse events concerning hypertension and hypothyroidism demonstrated that the values of RR were significantly higher in the axitinib group and lower risks were established in the patients treated with axitinib.
CONCLUSION
Therefore, axitinib was a better treatment option for metastatic renal cell carcinoma treatment than sorafenib, especially after failure of prior systemic therapies. This analysis revealed that axitinib had higher risks of hypertension and hypothyroidism and lower risks of rash and palmar-plantar erythrodysesthesia.
PubMed: 27354814
DOI: 10.2147/OTT.S100706 -
Molecular and Clinical Oncology Jul 2015Bevacizumab has demonstrated a survival benefit in patients with metastatic colorectal cancer (mCRC) when combined with chemotherapy. Several randomized clinical trials...
Bevacizumab has demonstrated a survival benefit in patients with metastatic colorectal cancer (mCRC) when combined with chemotherapy. Several randomized clinical trials comparing the efficacy and toxicity of vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs) against bevacizumab have been reported. The present meta-analysis was conducted to identify the potentially significant benefit of the combined treatment regimens in patients with mCRC. PubMed, Embase and Cochrane Library databases were searched for the randomized controlled trials published on or before September 2014, which compared the efficacy and toxicity of VEGFR TKIs with bevacizumab in combination with chemotherapy in patients with mCRC. The primary endpoints included progression-free survival (PFS), overall survival (OS) and overall response rate (ORR), and secondary endpoints were the toxicity profiles. Relative risks (RRs) with 95% confidence intervals (CIs) for response rate and adverse events (AEs) were calculated, as well as hazard ratios (HRs) for PFS and OS. The final analysis included 4 studies comprising a total of 1,929 intent-to-treat patients with mCRC, which compared VEGFR TKIs (cediranib and axitinib) plus chemotherapy with bevacizumab plus chemotherapy. Results demonstrated that VEGFR TKIs plus chemotherapy significantly resulted in a modest but significantly shorter PFS [hazard ratio (HR), 1.12; 95% CI, 1.00-1.25; P=0.05] compared with that of bevacizumab plus chemotherapy but not in OS (HR, 1.10; 95% CI, 0.88-1.17; P=0.87) and ORR (RR, 0.95; 95% CI, 0.85-1.05; P=0.30). VEGFR TKIs treatment showed a less favorable AE profile compared with bevacizumab, with higher rates of grade-III/IV diarrhea, fatigue, hypertension, neutropenia and thrombocytopenia, whereas a higher incidence of peripheral neuropathy associated with the bevacizumab group was observed. In conclusion, the addition of VEGFR TKIs to chemotherapy resulted in a modest but significantly shorter PFS but not in OS and ORR compared with bevacizumab. The VEGFR TKIs group showed a less favorable AE profile with higher rates of diarrhea, fatigue, hypertension, neutropenia and thrombocytopenia, whereas a higher incidence of peripheral neuropathy associated with the bevacizumab was observed.
PubMed: 26171215
DOI: 10.3892/mco.2015.572 -
PloS One 2014The optimal sequencing of targeted therapies for metastatic renal cell carcinoma (mRCC) is unknown. Observational studies with a variety of designs have reported... (Comparative Study)
Comparative Study Meta-Analysis Review
Comparative Effectiveness of Second-Line Targeted Therapies for Metastatic Renal Cell Carcinoma: A Systematic Review and Meta-Analysis of Real-World Observational Studies.
OBJECTIVE
The optimal sequencing of targeted therapies for metastatic renal cell carcinoma (mRCC) is unknown. Observational studies with a variety of designs have reported differing results. The objective of this study is to systematically summarize and interpret the published real-world evidence comparing sequential treatment for mRCC.
METHODS
A search was conducted in Medline and Embase (2009-2013), and conference proceedings from American Society of Clinical Oncology (ASCO), ASCO Genitourinary Cancers Symposium (ASCO-GU), and European Society for Medical Oncology (ESMO) (2011-2013). We systematically reviewed observational studies comparing second-line mRCC treatment with mammalian target of rapamycin inhibitors (mTORi) versus vascular endothelial growth factor (VEGF) tyrosine kinase inhibitors (TKI). Studies were evaluated for 1) use of a retrospective cohort design after initiation of second-line therapy, 2) adjustment for patient characteristics, and 3) use of data from multiple centers. Meta-analyses were conducted for comparisons of overall survival (OS) and progression-free survival (PFS).
RESULTS
Ten studies reported OS and exhibited significant heterogeneity in estimated second-line treatment effects (I2 = 68%; P = 0.001). Four of these were adjusted, multicenter, retrospective cohort studies, and these showed no evidence of heterogeneity (I2 = 0%; P = 0.61) and a significant association between second-line mTORi (>75% everolimus) and longer OS compared to VEGF TKI (>60% sorafenib) (HR = 0.82, 95% CI: 0.68 to 0.98) in a meta-analysis. Seven studies comparing PFS showed significant heterogeneity overall and among the adjusted, multicenter, retrospective cohort studies. Real-world observational data for axitinib outcomes was limited at the time of this study.
CONCLUSIONS
Real-world studies employed different designs and reported heterogeneous results comparing the effectiveness of second-line mTORi and VEGF TKI in the treatment of mRCC. Within the subset of adjusted, multicenter observational studies, second-line use of mTORi was associated with significantly prolonged survival compared with second-line use of VEGF TKI.
Topics: Carcinoma, Renal Cell; Humans; Kidney Neoplasms; Neoplasm Metastasis; Survival Analysis
PubMed: 25493562
DOI: 10.1371/journal.pone.0114264