Efficacy of systemic oncological treatments in patients with advanced pancreatic cancer at high risk of dying in the short or medium-term: overview of systematic reviews

BACKGROUND

Patients with advanced pancreatic cancer (PC) have a high risk of dying in the short or medium-term. This overview aimed to assess the evidence regarding systemic oncological treatments (SOT) versus supportive care for advanced PC.

METHODS

We searched for systematic reviews (SRs) in MEDLINE, Embase, The Cochrane Library, Epistemonikos, and PROSPERO. Two authors assessed eligibility independently. Data extraction and methodological quality assessment were conducted by one author and cross-checked by another one. We evaluated the overlap of primary studies, performed a de novo meta-analysis, and assessed the certainty of evidence. Primary outcomes were overall survival (OS), quality of life (QoL), functional status (FS), and toxicity.

RESULTS

We identified three SRs that assessed SOT versus supportive care in patients with advanced PC. All SRs had critically low methodological quality. At 12 months, OS improved with chemotherapy, radiotherapy followed by chemotherapy, and immunotherapy, but the certainty of the evidence supporting these findings is very low. The evidence on chemotherapy is very uncertain about its effects on QoL; it suggests a slight increase in toxicity and little to no difference in FS. The evidence on immunotherapy is very uncertain about its effects in toxicity.

CONCLUSIONS

The identified evidence is very uncertain about the benefits of oncological treatments on OS and QoL in patients with advanced PC with a high risk of dying in the short or medium-term, so its use should be proposed only to selected patients. Further studies that include a thorough assessment of patient-centred outcomes are needed.

Efficacy of systemic oncological treatments in patients with advanced esophageal or gastric cancers at high risk of dying in the middle and short term: an overview of systematic reviews

Background

Esophageal and gastric cancers are a significant public health problem worldwide, with most patients presenting with advanced-stage disease and, consequently, poor prognosis. Systemic oncological treatments (SOT) have been widely used over more conservative approaches, such as supportive care. Nevertheless, its effectiveness in this scenario is not sufficiently clear. This paper provides an overview of systematic reviews that assessed the effectiveness of SOT compared with the best supportive care (BSC) or placebo in patients with advanced esophageal or gastric cancers in an end-of-life context.

Methods

We searched MEDLINE, EMBASE, The Cochrane Library, Epistemonikos, and PROSPERO for eligible systematic reviews (SRs) published from 2008 onwards. The primary outcomes were overall survival (OS), progression-free survival (PFS), functional status, and toxicity. Two authors assessed eligibility and extracted data independently. We evaluated the methodological quality of included SRs using the AMSTAR-2 tool and the overlap of primary studies (corrected covered area, CCA). Also, we performed a de novo meta-analysis with data reported for each primary study when it was possible. We assessed the certainty of evidence using the GRADE approach.

Results

We identified 16 SRs (19 included trials) for inclusion within this overview. Most reviews had a critically low methodological quality, and there was a very high overlap of primary studies. It is uncertain whether SOT improves OS and PFS over more conservative approaches due to the very low certainty of evidence.

Conclusions

The evidence is very uncertain about the effectiveness of SOT for advanced esophageal or gastric cancers. High-quality SRs and further randomized clinical trials that include a thorough assessment of patient-centered outcomes are needed.

Trial registration

Open Science Framework, 10.17605/OSF.IO/7CHX6.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08330-5.

Brain mercury in neurodegenerative disorders

BACKGROUND

Trace element neurotoxicity has long been invoked as an etiologic factor for Alzheimer's disease. This study was conducted to determine the concentrations of mercury in seven different brain regions from deceased patients histologically confirmed with Alzheimer's disease or multiple sclerosis as compared to control subjects without known central nervous system and renal disorders. Brain mercury concentrations in all deceased subjects can arise from amalgam restorations, diet, and the working environment.

METHODS

Autopsy frozen specimens (control, Alzheimer's disease and multiple sclerosis) from seven brain regions, which included frontal cortex, temporal cortex, occipital cortex, putamen, hippocampus, corona radiata and corpus callosum were assayed for the concentrations of selenium using instrumental neutron activation analysis and mercury using radiochemical neutron activation analysis.

RESULTS

We found that the concentrations of mercury and the mercury/selenium molar ratios were significantly lower in the hippocampi of multiple sclerosis patients as compared to aged-matched controls. However, no statistically significant differences were detected for the concentrations of mercury and the mercury/ selenium molar ratios for the remaining six brain regions among these groups.

CONCLUSIONS

Since brain mercury concentrations from deceased subjects with either Alzheimer's disease or multiple sclerosis are not significantly higher than controls, the present study provides no scientific support that mercury plays a significant role in the pathogenesis of these neurologic disorders.

Mercury determination in nursing home patients with Alzheimer's disease

Trace-element neurotoxicity contributing to the development of Alzheimer's disease (AD) may be an important etiologic factor for this disorder. This clinical study was conducted to determine the urine concentrations of mercury (Hg) from patients with AD disorders. Within the confines of a nursing home, all subjects were exposed to the same environment and a diet that excluded seafood. The results of this study do not indicate that subjects with AD have a greater body burden of Hg, according to urinary excretion. This can be further evidence that Hg from amalgam restorations or diet is not related to etiology and pathogenesis of AD.

Determination of blood mercury concentrations in Alzheimer's patients

Trace element neurotoxicity can be an etiologic factor for Alzheimer's disease. This cross sectional clinical study determined blood mercury in patients with diagnosed Alzheimer's disease as compared to control subjects without known central nervous system and renal disorders. Unique within the confines of a nursing home, all subjects were exposed to the same environment and consumed a diet without fish and seafood for a period of three months prior to the study. The results of this study show that blood mercury concentrations detected in subjects with Alzheimer's disease were not statistically different than that of control subjects. Ratios of blood mercury to blood selenium were also determined and no statistical difference was found between these two groups.