Regional cerebral glucose metabolism in patients with secondary depressive episodes after fatal pancreatic cancer diagnosis

Emotional distress, brain functioning, and biobehavioral processes in cancer patients: a neuroimaging review and future directions

Despite emerging evidence that distress and adversity can contribute to negative health outcomes in cancer, little is known about the brain networks, regions, or circuits that can contribute to individual differences in affect/distress states and health outcomes in treated cancer patients. To understand the state-of-the-science in this regard, we reviewed neuroimaging studies with cancer patients that examined the associations between negative affect (distress) and changes in the metabolism or structure of brain regions. Cancer patients showed changes in function and/or structure of key brain regions such as the prefrontal cortex, thalamus, amygdala, hippocampus, cingulate cortex (mainly subgenual area), hypothalamus, basal ganglia (striatum and caudate), and insula, which are associated with greater anxiety, depression, posttraumatic stress disorder (PTSD) symptoms, and distress. These results provide insights for understanding the effects of these psychological and emotional factors on peripheral stress-related biobehavioral pathways known to contribute to cancer progression and long-term health outcomes. This line of work provides leads for understanding the brain-mediated mechanisms that may explain the health effects of psychosocial interventions in cancer patients and survivors. A multilevel and integrated model for distress management intervention effects on psychological adaptation, biobehavioral processes, cancer pathogenesis, and clinical outcomes is proposed for future research.

Gender-disease interaction on brain cerebral metabolism in cancer patients with depressive symptoms

BACKGROUND

Cancer patients are accompanied with high morbidity of depression, and gender effects are known to inhabit in the depressive episodes. This study aimed to explore the gender effects in cancer patients, and the relationship between gender-cancer factors and the depression symptoms.

METHODS

The 18F-FDG PET scans of 49 cancer patients and 48 normal controls were included. We used voxel-wise analysis to explore the effects of cancer factor and gender factor in cerebral glucose metabolism. Beck Depression Inventory was utilized to quantify the depression symptoms in cancer patients.

RESULTS

Our results showed significant cancer main effects primarily in superior frontal gyrus and parietal gyrus; and significant gender main effects primarily in cerebellum posterior lobe, inferior temporal gyrus. Significant gender-by-cancer interaction effects were also observed, which primarily located in superior frontal gyrus. We showed the metabolic intensities of the 5 aforementioned clusters were related to the mental stress of depressive emotion.

CONCLUSIONS

Our results suggested that males and females have different psychological endurance when facing cancer diagnosis or preventing depression. Furthermore, the cerebral abnormal metabolism might serve as a depressive indicator for cancer patients. The present findings provided supporting evidence for abnormal cerebral glucose metabolism affected by gender factor in cancer patients with mental stress of depressive emotion, and these brain regions should be concerned in clinic.

Understanding the Pathophysiology of Psychological Distress and Pancreatic Cancer: A Systematic Review

BACKGROUND

Psychological distress is highly prevalent in patients with pancreatic cancer (PC), yet little is known about the pathophysiology underlying the relationship between these 2 diseases. Our aim was to systematically review the evidence examining the pathophysiological mechanisms of the association between PC and psychological distress.

METHODS

A systematic review of the literature was conducted using MEDLINE, Embase, PsychINFO, and CINAHL databases and reported according to the preferred reporting items for systematic reviews and meta-analyses guidelines. Studies examining the pathophysiological mechanisms between PC and psychological distress were included for analysis.

RESULTS

Eight studies were identified that fulfilled inclusion criteria. Four mechanisms were identified accounting for the possible relationship between psychological distress and PC, including (1) stress-induced β-adrenergic signaling, (2) interleukin-6-mediated effects, (3) kynurenine pathway upregulation, and (4) altered cerebral glucose metabolism.

CONCLUSIONS

The relationship between psychological distress and PC is complex, and our understanding of these mechanisms may have implications for holistic clinical management and oncological outcome. The evidence exploring the pathophysiology of this interaction is sparse, but most well established with regard to the stress-induced β-adrenergic signaling mechanism. Further studies in larger cohorts are required to elucidate the relationship between PC and psychological distress to be able to identify therapeutic targets for both conditions.

Subgenual cingulate cortical activity predicts the efficacy of electroconvulsive therapy

Electroconvulsive therapy (ECT) is the most effective treatment for depression, yet its mechanism of action is unknown. Our goal was to investigate the neurobiological underpinnings of ECT response using longitudinally collected resting-state functional magnetic resonance imaging (rs-fMRI) in 16 patients with treatment-resistant depression and 10 healthy controls. Patients received bifrontal ECT 3 times a week under general anesthesia. We acquired rs-fMRI at three time points: at baseline, after the 1st ECT administration and after the course of the ECT treatment; depression was assessed with the Hamilton Depression Rating Scale (HAM-D). The primary measure derived from rs-fMRI was fractional amplitude of low frequency fluctuation (fALFF), which provides an unbiased voxel-wise estimation of brain activity. We also conducted seed-based functional connectivity analysis based on our primary findings. We compared treatment-related changes in HAM-D scores with pre- and post-treatment fALFF and connectivity measures. Subcallosal cingulate cortex (SCC) demonstrated higher BOLD signal fluctuations (fALFF) at baseline in depressed patients, and SCC fALFF decreased over the course of treatment. The baseline level of fALFF of SCC predicted response to ECT. In addition, connectivity of SCC with bilateral hippocampus, bilateral temporal pole, and ventromedial prefrontal cortex was significantly reduced over the course of treatment. These results suggest that the antidepressant effect of ECT may be mediated by downregulation of SCC activity and connectivity. SCC function may serve as an important biomarker of target engagement in the development of novel therapies for depression that is resistant to treatment with standard medications.

The relationship between pain management and psychospiritual distress in patients with advanced cancer following admission to a palliative care unit

Background

Although many cross-sectional studies have demonstrated the association between cancer pain and psychospiritual distress, the time-dependent relationship has not been fully explored. For that reason, this study aims to investigate the time-dependent relationship between psychospiritual distress and cancer pain management in advanced cancer patients.

Methods

This is a prospective observational study. Two hundred thirty-seven advanced cancer patients were recruited from a palliative care unit in Taiwan. Demographic and clinical data were retrieved at admission. Pain and psychospiritual distress (i.e.: anxiety, depression, anger, level of family and social support, fear of death) were assessed upon admission and one week later, by using a “Symptom Reporting Form”. Patients were divided into two groups according to the pain status one week post-admission (improved versus not improved groups).

Results

One hundred sixty-three (68.8 %) patients were assigned to the improved group, and 74 (31.2 %) patients were assigned to the not improved group. There were no differences in the psychospiritual variables between groups upon admission. In overall patients, all psychospiritual variables improved one week post-admission, but the improvement of depression and family/social support in the not improved group was not significant. Consistent with this, for depression scores, there was a statistically significant pain group x time interaction effect detected, meaning that the pain group effect on depression scores was dependent on time.

Conclusions

We demonstrated a time-dependent relationship between depression and pain management in advanced cancer patients. Our results suggest that poor pain management may be associated with intractable depression. The inclusion of interventions that effectively improve psychospiritual distress may contribute to pain management strategies for advanced cancer patients.

Imaging cerebral tryptophan metabolism in brain tumor-associated depression

BACKGROUND

Depression in patients with brain tumors is associated with impaired quality of life and shorter survival. Altered metabolism of tryptophan to serotonin and kynurenine metabolites may play a role in tumor-associated depression. Our recent studies with alpha[(11)C]methyl-L-tryptophan (AMT)-PET in brain tumor patients indicated abnormal tryptophan metabolism not only in the tumor mass but also in normal-appearing contralateral brain. In the present study, we explored if tryptophan metabolism in such brain regions is associated with depression.

METHODS

Twenty-one patients (mean age: 57 years) with a brain tumor (10 meningiomas, 8 gliomas, and 3 brain metastases) underwent AMT-PET scanning. MRI and AMT-PET images were co-registered, and AMT kinetic parameters, including volume of distribution (VD', an estimate of net tryptophan transport) and K (unidirectional uptake, related to tryptophan metabolism), were measured in the tumor mass and in unaffected cortical and subcortical regions contralateral to the tumor. Depression scores (based on the Beck Depression Inventory-II [BDI-II]) were correlated with tumor size, grade, type, and AMT-PET variables.

RESULTS

The mean BDI-II score was 12 ± 10 (range: 2-33); clinical levels of depression were identified in seven patients (33 %). High BDI-II scores were most strongly associated with high thalamic AMT K values both in the whole group (Spearman's rho = 0.63, p = 0.004) and in the subgroup of 18 primary brain tumors (r = 0.68, p = 0.004). Frontal and striatal VD' values were higher in the depressed subgroup than in non-depressed patients (p < 0.05); the group difference was even more robust when moderately/severely depressed patients were compared to patients with no/mild depression (frontal: p = 0.005; striatal: p < 0.001). Tumor size, grade, and tumor type were not related to depression scores.

CONCLUSIONS

Abnormalities of tryptophan transport and metabolism in the thalamus, striatum, and frontal cortex, measured by PET, are associated with depression in patients with brain tumor. These changes may indicate an imbalance between the serotonin and kynurenine pathways and serve as a molecular imaging marker of brain tumor-associated depression.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02367469.

Antidepressant Effects of Electroconvulsive Therapy Correlate With Subgenual Anterior Cingulate Activity and Connectivity in Depression

The mechanisms underlying the effects of electroconvulsive therapy (ECT) in major depressive disorder (MDD) are not fully understood. Resting-state functional magnetic resonance imaging (rs-fMRI) is a new tool to study the effects of brain stimulation interventions, particularly ECT. The authors aim to investigate the mechanisms of ECT in MDD by rs-fMRI.They used rs-fMRI to measure functional changes in the brain of first-episode, treatment-naive MDD patients (n = 23) immediately before and then following 8 ECT sessions (brief-pulse square-wave apparatus, bitemporal). They also computed voxel-wise amplitude of low-frequency fluctuation (ALFF) as a measure of regional brain activity and selected the left subgenual anterior cingulate cortex (sgACC) to evaluate functional connectivity between the sgACC and other brain regions.Increased regional brain activity measured by ALFF mainly in the left sgACC following ECT. Functional connectivity of the left sgACC increased in the ipsilateral parahippocampal gyrus, pregenual ACC, contralateral middle temporal pole, and orbitofrontal cortex. Importantly, reduction in depressive symptoms were negatively correlated with increased ALFF in the left sgACC and left hippocampus, and with distant functional connectivity between the left sgACC and contralateral middle temporal pole. That is, across subjects, as depression improved, regional brain activity in sgACC and its functional connectivity increased in the brain.Eight ECT sessions in MDD patients modulated activity in the sgACC and its networks. The antidepressant effects of ECT were negatively correlated with sgACC brain activity and connectivity. These findings suggest that sgACC-associated prefrontal-limbic structures are associated with the therapeutic effects of ECT in MDD.

Preliminary study of brain glucose metabolism changes in patients with lung cancer of different histological types

BACKGROUND

Cerebral glucose metabolism changes are always observed in patients suffering from malignant tumors. This preliminary study aimed to investigate the brain glucose metabolism changes in patients with lung cancer of different histological types.

METHODS

One hundred and twenty patients with primary untreated lung cancer, who visited People's Hospital of Zhengzhou University from February 2012 to July 2013, were divided into three groups based on histological types confirmed by biopsy or surgical pathology, which included adenocarcinoma (52 cases), squamous cell carcinoma (43 cases), and small-cell carcinoma (25 cases). The whole body 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) of these cases was retrospectively studied. The brain PET data of three groups were analyzed individually using statistical parametric maps (SPM) software, with 50 age-matched and gender-matched healthy controls for comparison.

RESULTS

The brain resting glucose metabolism in all three lung cancer groups showed regional cerebral metabolic reduction. The hypo-metabolic cerebral regions were mainly distributed at the left superior and middle frontal, bilateral superior and middle temporal and inferior and middle temporal gyrus. Besides, the hypo-metabolic regions were also found in the right inferior parietal lobule and hippocampus in the small-cell carcinoma group. The area of the total hypo-metabolic cerebral regions in the small-cell carcinoma group (total voxel value 3255) was larger than those in the adenocarcinoma group (total voxel value 1217) and squamous cell carcinoma group (total voxel value 1292).

CONCLUSIONS

The brain resting glucose metabolism in patients with lung cancer shows regional cerebral metabolic reduction and the brain hypo-metabolic changes are related to the histological types of lung cancer.

How are patient populations characterized in studies investigating depression in advanced cancer? Results from a systematic literature review

CONTEXT

Prevalence rates of depression in patients with advanced cancer vary considerably. This may be because of heterogeneous samples and use of different assessment methods. Adequate sample descriptions and consistent use of measures are needed to be able to generalize research findings and apply them to clinical practice.

OBJECTIVES

Our objective was twofold: First, to investigate which clinically important variables were used to describe the samples in studies of depression in patients with advanced cancer; and second, to examine the methods used for assessing and classifying depression in these studies.

METHODS

PubMed, PsycINFO, Embase, and CINAHL were searched combining search term groups representing "depression," "palliative care," and "advanced cancer" covering 2007-2011. Titles and abstracts were screened, and relevant full-text articles were evaluated independently by two authors. Information on 32 predefined variables on cancer disease, treatment, sociodemographics, depression-related factors, and assessment methods was extracted from the articles.

RESULTS

After removing duplicates, 916 citations were screened of which 59 articles were retained. Age, gender, and stage of the cancer disease were the most frequently reported variables. Depression-related variables were rarely reported, for example, antidepressant use (17%) and previous depressive episodes (12%). Only 25% of the studies assessed and classified depression according to a validated diagnostic system.

CONCLUSION

Current practice for describing sample characteristics and assessing depression varies greatly between studies. A more standardized practice is recommended to enhance the generalizability and utility of findings. Stakeholders are encouraged to work toward a common standard for sample descriptions.

Quantification of Tc-99m-ethyl cysteinate dimer brain single photon emission computed tomography images using statistical probabilistic brain atlas in depressive end-stage renal disease patients: Correlation with disease severity and symptom factors

This study adapted a statistical probabilistic anatomical map of the brain for single photon emission computed tomography images of depressive end-stage renal disease patients. This research aimed to investigate the relationship between symptom clusters, disease severity, and cerebral blood flow. Twenty-seven patients (16 males, 11 females) with stages 4 and 5 end-stage renal disease were enrolled, along with 25 healthy controls. All patients underwent depressive mood assessment and brain single photon emission computed tomography. The statistical probabilistic anatomical map images were used to calculate the brain single photon emission computed tomography counts. Asymmetric index was acquired and Pearson correlation analysis was performed to analyze the correlation between symptom factors, severity, and regional cerebral blood flow. The depression factors of the Hamilton Depression Rating Scale showed a negative correlation with cerebral blood flow in the left amygdale. The insomnia factor showed negative correlations with cerebral blood flow in the left amygdala, right superior frontal gyrus, right middle frontal gyrus, and left middle frontal gyrus. The anxiety factor showed a positive correlation with cerebral glucose metabolism in the cerebellar vermis and a negative correlation with cerebral glucose metabolism in the left globus pallidus, right inferior frontal gyrus, both temporal poles, and left parahippocampus. The overall depression severity (total scores of Hamilton Depression Rating Scale) was negatively correlated with the statistical probabilistic anatomical map results in the left amygdala and right inferior frontal gyrus. In conclusion, our results demonstrated that the disease severity and extent of cerebral blood flow quantified by a probabilistic brain atlas was related to various brain areas in terms of the overall severity and symptom factors in end-stage renal disease patients.

Mood dysregulation and stabilization: perspectives from emotional cognitive neuroscience

Mood is conceptualized as a long-lasting emotional state, which can have profound implications for mental and physical health. The development of neuroimaging methods has enabled significant advances towards elucidating the mechanisms underlying regulation of mood and emotion; however, our understanding of mood and emotion dysregulation in stress-related psychiatric disorders is still largely lacking. From the cognitive-affective neuroscience perspective, achieving deeper, more mechanistic understanding of mood disorders necessitates detailed understanding of specific components of neural systems involved in mood dysregulation and stabilization. In this review, we provide an overview of neural systems implicated in the development of a long-term negative mood state, as well as those related to emotion and emotion regulation, and discuss their proposed involvement in mood and anxiety disorders.

Localizing sadness activation within the subgenual cingulate in individuals: a novel functional MRI paradigm for detecting individual differences in the neural circuitry underlying depression

Variations in frontal lobe (FL) functional anatomy, especially the subgenual cingulate gyrus (SGC) suggest that mapping on an individual rather than group level may give greater insight regarding dysregulation of the neural circuitry involved in depression, as well as potentially provide more specific or individualized treatment plans for depressed patients. We designed a functional MRI task capable of imaging FL activity in individuals, including the SGC region, using a transient sadness paradigm. We sought to develop a method that may better detect individual differences of FL subregions related to sadness, since this region has been implicated to show dysregulation in depression. The task was based on a block design that also accommodates individual differences in responsivity to a sadness induction paradigm. Individual differences from nine non-depressed healthy volunteers were analyzed. We also performed functional connectivity analyses to further characterize our findings to the networks associated with the SGC in each individual. The study was designed to account for individual variation rather than using a true experimental design; therefore, no control group was necessary. As expected, due to inter-individual variability, the specific site of SGC activation during sadness varied across individuals. Activation was also observed in other brain regions consistent with other studies of induced sadness and depression. Patterns of functional connectivity to the SGC also highlighted neural circuits known to subserve sadness and depression. This task promises to more precisely localize a given individual's functional organization of the brain circuitry underlying sadness, and potentially depression, in an efficient, standardized way. This task could potentially aid in providing individualized targets in the treatment of depression.

Neurocircuitry of mood disorders

This review begins with a brief historical overview of attempts in the first half of the 20th century to discern brain systems that underlie emotion and emotional behavior. These early studies identified the amygdala, hippocampus, and other parts of what was termed the 'limbic' system as central parts of the emotional brain. Detailed connectional data on this system began to be obtained in the 1970s and 1980s, as more effective neuroanatomical techniques based on axonal transport became available. In the last 15 years these methods have been applied extensively to the limbic system and prefrontal cortex of monkeys, and much more specific circuits have been defined. In particular, a system has been described that links the medial prefrontal cortex and a few related cortical areas to the amygdala, the ventral striatum and pallidum, the medial thalamus, the hypothalamus, and the periaqueductal gray and other parts of the brainstem. A large body of human data from functional and structural imaging, as well as analysis of lesions and histological material indicates that this system is centrally involved in mood disorders.

Imaging phenotypes of major depressive disorder: genetic correlates

Imaging techniques are a potentially powerful method of identifying phenotypes that are associated with, or are indicative of, a vulnerability to developing major depressive disorder (MDD). Here we identify seven promising MDD-associated traits identified by magnetic resonance imaging (MRI) or positron emission tomography (PET). We evaluate whether these traits are state-independent, heritable endophenotypes, or state-dependent phenotypes that may be useful markers of treatment efficacy. In MDD, increased activity of the amygdala in response to negative stimuli appears to be a mood-congruent phenomenon, and is likely moderated by the 5-HT transporter gene (SLC6A4) promoter polymorphism (5-HTTLPR). Hippocampal volume loss is characteristic of elderly or chronically-ill samples and may be impacted by the val66met brain-derived neurotrophic factor (BDNF) gene variant and the 5-HTTLPR SLC6A4 polymorphism. White matter pathology is salient in elderly MDD cohorts but is associated with cerebrovascular disease, and is unlikely to be a useful marker of a latent MDD diathesis. Increased blood flow or metabolism of the subgenual anterior cingulate cortex (sgACC), together with gray matter volume loss in this region, is a well-replicated finding in MDD. An attenuation of the usual pattern of fronto-limbic connectivity, particularly a decreased temporal correlation in amygdala-anterior cingulate cortex (ACC) activity, is another MDD-associated trait. Concerning neuroreceptor PET imaging, decreased 5-HT(1A) binding potential in the raphe, medial temporal lobe, and medial prefrontal cortex (mPFC) has been strongly associated with MDD, and may be impacted by a functional single nucleotide polymorphism in the promoter region of the 5-HT(1A) gene (HTR1A: -1019 C/G; rs6295). Potentially indicative of inter-study variation in MDD etiology or mood state, both increased and decreased binding potential of the 5-HT transporter has been reported. Challenges facing the field include the problem of phenotypic and etiological heterogeneity, technological limitations, the confounding effects of medication, and non-disease related inter-individual variation in brain morphology and function. Further advances are likely as epigenetic, copy-number variant, gene-gene interaction, and genome-wide association (GWA) approaches are brought to bear on imaging data.

Symptom indicator of severity of depression in cancer patients: a comparison of the DSM-IV criteria with alternative diagnostic criteria

OBJECTIVE

The objective of this study was to explore the performances of several diagnostic criteria items for judging the severity of major depression among cancer patients.

METHOD

Using modern item response theory, we examined the performances of the diagnostic criteria outlined by the DSM-IV and two sets of conceptual diagnostic criteria (the Endicott and the Cavanaugh criteria) in a series of 728 cancer patients who had been diagnosed with major depression using an inclusive approach.

RESULTS

While all the DSM-IV diagnostic criteria, including feelings of worthlessness and suicidal ideation, had a low ability for discriminating the severity of depression, two proposed items (not participating in medical care and social withdrawal) appeared to be good markers of moderately severe major depressive disorder among cancer patients. In addition, the items "fearfulness or depressed appearance in face or body posture" and "brooding, self-pity or pessimism" may be good markers for mild major depressive disorders, while the item "cannot be cheered up, doesn't smile, no response to good news or funny situations" may be a good marker for severe major depressive disorder.

CONCLUSIONS

The findings of the present study suggest that alternative criteria may have utility in diagnosing depression severity in cancer patients.

Neurostimulatory therapeutics in management of treatment-resistant depression with focus on deep brain stimulation

Treatment-resistant depression continues to pose a major medical challenge, as up to one-third of patients with major depressive disorder fail to have an adequate response to standard pharmacotherapies. An improved understanding of the complex circuitry underlying depressive disorders has fostered an explosion in the development of new, nonpharmacological approaches. Each of these treatments seeks to restore normal brain activity via electrical or magnetic stimulation. In this article, the authors discuss the ongoing evolution of neurostimulatory treatments for treatment-resistant depression, reviewing the methods, efficacy, and current research on electroconvulsive therapy, repetitive transcranial magnetic stimulation, magnetic seizure therapy, focal electrically administered stimulated seizure therapy, transcranial direct current stimulation, chronic epidural cortical stimulation, and vagus nerve stimulation. Special attention is given to deep brain stimulation, the most focally targeted approach. The history, purported mechanisms of action, and current research are outlined in detail. Although deep brain stimulation is the most invasive of the neurostimulatory treatments developed to date, it may hold significant promise in alleviating symptoms and improving the quality of life for patients with the most severe and disabling mood disorders.

Improved discrimination of benign and malignant lesions on FDG PET/CT, using comparative activity ratios to brain, basal ganglia, or cerebellum

PURPOSE

This study demonstrates a simple background correction method, which improves the discrimination of benign from malignant lesions on FDG PET-CT imaging, using activity ratios compared with brain, basal ganglia, or cerebellum.

METHODS

Standardized uptake values (SUVs) and comparative activity ratios (CARs) were determined for FDG uptake in 92 lesions (39 benign and 53 malignant) in 49 patients. Reference tissues included cerebral cortex, basal ganglia, cerebellum, lung, liver, and aortic blood pool. Discriminant power for each CAR was evaluated as malignant-to-benign ratio of mean uptake and ratio of intermediate-likelihood lesions to total number of lesions.

RESULTS

Uncorrected SUV varied widely for malignant and benign lesions, with considerable overlap. Ratio of mean uptake for malignant lesions versus benign lesions was lowest for uncorrected SUVAVG and SUVAVG/liver (1.92), and highest for SUVMAX/cerebral cortex (3.52). Lesions could be separated into very high (> 90%), very low (< 10%), and intermediate (> or = 10% and < or = 90%) likelihood of malignancy. The ratio of intermediate-likelihood lesions to the total number of lesions was greatest for SUVAVG (0.42) and lowest for SUVMAX/basal ganglia (0.22).

CONCLUSIONS

Ability to discriminate malignant from benign lesions was enhanced by using CARs derived from cerebral cortex, basal ganglia, or cerebellum. Using a 3-tiered diagnostic schema, most lesions could be assigned to categories of very high or very low likelihood of malignancy, with a significant reduction in indeterminant lesions, compared with uncorrected SUV.

Cerebral glucose metabolism abnormalities in patients with major depressive symptoms in pre-dialytic chronic kidney disease: statistical parametric mapping analysis of F-18-FDG PET, a preliminary study

AIMS

The aim of the present study was to investigate the relationship between depressive symptoms and cerebral glucose metabolism in pre-dialytic chronic kidney disease (PDCKD) patients.

METHODS

Twenty-one patients with stage 5 CKD and 21 healthy volunteers underwent depressive mood assessment and statistical parametric mapping (SPM) using F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET).

RESULTS

Several voxel clusters of significantly decreased cerebral glucose metabolism were found in PDCKD patients. The largest cluster was left prefrontal cortex (Brodmann area [BA] 9). The second largest cluster was also left prefrontal cortex (BA 9). The third largest clusters were right prefrontal cortex (BA 10) and right basolateral prefrontal cortex (BA 46). Other brain areas also showed decreased cerebral glucose metabolism including left anterior cingulate gyrus (BA 32), left premotor cortex (BA 6), left transverse temporal gyrus (BA 41), left superior temporal gyrus (BA 42), right basolateral prefrontal cortex (BA 44), right inferior parietal lobule (BA 39), left middle temporal gyrus (BA 19), and left angular gyrus (BA 39). Hypermetabolized brain areas, however, were not found in PDCKD patients compared to normal controls. For the right orbitofrontal cortex there was a negative correlation of cerebral glucose metabolism with Hamilton Depression Rating Scale (HDRS) in PDCKD patients (BA 11).

CONCLUSION

PDCKD patients with depressive symptoms had decreased cerebral glucose metabolism in several brain areas. For the right orbitofrontal cortex there was a negative correlation with HDRS in PDCKD patients. The present findings provide functional neuroimaging support for abnormal cerebral glucose metabolism in PDCKD patients with depressive symptoms.

The subgenual anterior cingulate cortex in mood disorders

The anterior cingulate cortex (ACC) ventral to the genu of the corpus callosum has been implicated in the modulation of emotional behavior on the basis of neuroimaging studies in humans and lesion analyses in experimental animals. In a combined positron emission tomography/magnetic resonance imaging study of mood disorders, we demonstrated that the mean gray matter volume of this "subgenual" ACC (sgACC) cortex is abnormally reduced in subjects with major depressive disorder (MDD) and bipolar disorder, irrespective of mood state. Neuropathological assessments of sgACC tissue acquired postmortem from subjects with MDD or bipolar disorder confirmed the decrement in gray matter volume, and revealed that this abnormality was associated with a reduction in glia, with no equivalent loss of neurons. In positron emission tomography studies, the metabolic activity was elevated in this region in the depressed relative to the remitted phases of the same MDD subjects, and effective antidepressant treatment was associated with a reduction in sgACC activity. Other laboratories replicated and extended these findings, and the clinical importance of this treatment effect was underscored by a study showing that deep brain stimulation of the sgACC ameliorates depressive symptoms in treatment-resistant MDD. This article discusses the functional significance of these findings within the context of the preclinical literature that implicates the putative homologue of this region in the regulation of emotional behavior and stress response. In experimental animals, this region participates in an extended "visceromotor network" of structures that modulates autonomic/neuroendocrine responses and neurotransmitter transmission during the neural processing of reward, fear, and stress. These data thus hold important implications for the development of neural models of depression that can account for the abnormal motivational, neuroendocrine, autonomic, and emotional manifestations evident in human mood disorders.

Depression and cancer: recent data on clinical issues, research challenges and treatment approaches

PURPOSE OF REVIEW

Clinical guidelines for depression screening, assessment and management in the oncologic field and palliative care are becoming paramount in routine cancer care. This psychiatric comorbidity has several impacts on quality of life, anticancer treatment compliance, hospital stay duration, health-care costs, morbidity and possibly mortality even if discordant reports exist.

RECENT FINDINGS

Recent development of brain imaging techniques (MRI, positron emission tomography), neurobiological and genetic tools allow new understanding of the pathophysiology process of depressive disorders in cancer populations besides the usual endocrinologic and psychoneuroimmunologic hypothesis. Broader indications besides depressive or anxiety disorders appear or must be investigated for the new generation of antidepressants (selective serotonin reuptake inhibitors, serotonin and norepinephrine reuptake inhibitors, noradrenergic specific serotonergic antidepressants) in oncology, such as hot flashes, neuropathic pain, fatigue, anorexia/cachexia. Psychosocial interventions seem to have a slight impact on well-being, quality of life and depressive symptomatology but not on survival.

SUMMARY

The present article reviews recent literature on depression and cancer and highlights practical assessment and detection of depression, biological and physiopathological correlates and its pharmacologic and psychosocial treatment. Implementation of these several techniques must be supported by ongoing research about the complex relation between depressive disorders and generally mental health and oncology.

Depression in cancer patients: a critical review

Cancer patients experience several stressors and emotional upheavals. Fear of death, interruption of life plans, changes in body image and self-esteem, changes in social role and lifestyle are all important issues to be faced. Moreover, Depressive Disorders may impact the course of the disease and compliance. The cost and prevalence, the impairment caused, and the diagnostic and therapeutic uncertainty surrounding depressive symptoms among cancer patients make these conditions a priority for research. In this article we discuss recent data, focusing on detection of Depressive Disorders, biological correlates, treatments and unmet needs of depressed cancer patients.