Psychosocial factors in the etiology of breast cancer: review of a popular link

Searching for the emotional roots of breast cancer: A cross-disciplinary analysis integrating psychology, Chinese medicine, and oncology biomarkers

OBJECTIVE

We employed a multidisciplinary approach incorporating theoretical ideas, clinical experience, psychology, physiology, traditional Chinese medicine (CM), modern practice of CM, and oncology to explore the effect of patients' repression of negative emotions and traumatic events on breast cancer (BC) pathogenesis.

METHODS

BC female patients, older than 18 years of age, with available pathology reports who were treated at Rabin Medical Center were recruited. All participants completed questionnaires regarding medical history, behavioral tendencies, negative emotions, trauma, symptoms, and pathology (from a CM perspective). Data on tumor characteristics were collected from the pathology reports. The associations were examined using hierarchical binary logistic regressions.

RESULTS

A total of 155 BC patients were enrolled. The median age was 52 years, with a range of 26-79; 95% were mothers; 28% had estrogen receptor (ER)-negative BC, 52% had progesterone receptor (PR)-negative BC, 48% had human epidermal growth factor receptor 2-negative BC, and antigen Ki-67 ≥ 20% was reported for 52% of tumors. Statistically significant associations were found between the emotional markers (sense of motherhood failure, and lack of self-fulfillment), avoidance behavior, and physical symptoms that are related to emotional repression based on CM. Significant associations were also found between variables associated with physical symptoms of emotional repression, which involves the production and accumulation of non-substantial phlegm (i.e., "high-lipid Qi-like microscopic phlegm"), avoidance behavior which unconsciously uses "high-lipid Qi-like microscopic phlegm" in order to achieve emotional repression, and tumor parameters including tumor grade, PR status, and Ki-67. Patients with higher levels of "high-lipid Qi-like microscopic phlegm" were more likely to have tumors with worse prognosis (PR-negative, higher grade, and higher Ki-67).

CONCLUSION

We demonstrated a relationship between emotional parameters, behavioral tendencies, CM parameters, and oncologic parameters in BC. Additional research is warranted to explore these associations and their relevance to clinical practice.

Prevalence of depression, trait anxiety, and social support during the diagnostic phases of breast cancer

Objective

This study aims to determine the prevalence of depression, trait anxiety, and social support among women suspected of breast cancer (BC) and to investigate the association of these factors with the diagnosis of BC.

Methods

A cross-sectional study was conducted on 745 women who presented with breast symptoms in a university breast clinic in Malaysia. Participants were instructed to respond to self-report questionnaires on depression, trait anxiety, and social support while they were waiting for assessment of their suspected BC. The final diagnoses of these patients were traced one month after examining their medical records. Descriptive statistics were performed to examine the socio-demographic and clinical characteristics of all participants. A multiple regression analysis was carried out to determine the association of the abovementioned factors with the diagnosis of BC.

Results

The analysis showed that BC was diagnosed in 109 (14.6%), benign breast disease (BBD) in 550 (73.8%), and healthy breast (HB) in 86 (11.5%) women. The prevalence of depression was 53.2% in women with BC, 53.6% in women with BBD, and 60.5% in women with HB prior to diagnosis. The prevalence of trait anxiety was 33%. Mean scores for trait anxiety were 42.2 ± 9.0 and 41.8 ± 9.1 for the BC group and BBD group, respectively. The level of perceived social support was similar in all three groups.

Conclusion

We found no significant difference in depression, trait anxiety, and social support among women with newly diagnosed BC, BBD, and HB in women with breast symptoms while undergoing diagnostic evaluation. A longitudinal study is essential to establish the association between chronic mental stress and BC.

The Role of Stress in Breast Cancer Incidence: Risk Factors, Interventions, and Directions for the Future

Stress is a common belief among breast cancer patients and the public to explain variation in breast cancer incidence. Epidemiological studies interrogating the relationship between stress and cancer have reported mixed results. The impact of the topic and the lack of consensus has sparked this review of the literature to investigate gaps in knowledge and identify areas of research. We first present a brief summary of the biopsychosocial model generally used to conduct research on stress. We then divide the overview of the literature into areas of research focus. These include the role of distressing life events in breast cancer incidence, the role of adverse childhood events in later breast cancer incidence, the importance of race and socioeconomic status (SES) as social determinants of breast cancer incidence, and the specific role of chronic stress in relation to breast cancer. For each topic, we discuss the potential of stress as a risk factor and possible intervention strategies that could reduce the effects of stress. We then identify further research questions to be probed to fill the gaps in knowledge. We conclude with a discussion of future research directions for stress research as it relates to breast cancer incidence.

Stimulatory Effect of Indolic Hormone on As2O3 Cytotoxicity in Breast Cancer Cells: NF-κB-dependent Mechanism of Action of Melatonin

The advent of combination therapy unprecedentedly shifted the paradigm of cancer treatment by reconstructing the conventional protocols. By identifying the anti-tumoral activity for different natural products, recent interest has focused on inventing the combined- modality strategies to increase the cure rates of cancer, while reducing the toxic side effects of current intensive regimens. To evaluate whether melatonin, indolic hormone produced mainly by the pineal gland, could enhance the pro-apoptotic effect of arsenic trioxide (As₂O₃) in breast cancer, MCF-7 cells were treated with As₂O₃-plus- melatonin and then the survival, proliferative rate, caspase-3 activity, and mRNA expression level of anti- apoptosis target genes of NF-κB were investigated. Our results delineated that exposure of MCF-7 cells to As₂O₃ not only reduced the survival of the cells, but also induced a caspsase-3-dependent apoptotic cell death. Noteworthy, an enhanced induction of apoptosis was found using As₂O₃ in combination with melatonin. Moreover, RQ-PCR analysis revealed that the enhanced cytotoxic effect of As₂O₃ in the presence of melatonin is mediated, at least partly, through suppressing the expression of NF-κB anti-apoptotic target genes such as MCL-1, BCL-2, survivin, XIAP, and c-IAP1 in breast cancer cells. The resulting data showed that As₂O₃, either alone or in combination with melatonin, exerted significant cytotoxic effect against MCF-7 cells. However, further investigations are needed to provide valuable clues for expediting this combination as a therapeutic strategy for breast cancer.

Expressive writing intervention and self-reported physical health out-comes - Results from a nationwide randomized controlled trial with breast cancer patients

The objective was to examine the effect of Expressive Writing Intervention (EWI) on self-reported physical symptoms and healthcare utilization in a nationwide randomized controlled trial with Danish women treated for primary breast cancer, and to explore participant characteristics related to emotion regulation as possible moderators of the effect. Women who had recently completed treatment for primary breast cancer (n = 507) were randomly assigned to three 20 min. home-based writing exercises, one week apart, focusing on emotional disclosure (EWI) of a distressing experience (their cancer or a non-cancer topic) or a non-disclosing topic (control). Outcomes were self-reported physical symptoms and healthcare utilization (visits and telephone contacts with GP) 3 and 9 months post-intervention. Potential moderators were repressive coping, alexithymia, rumination, social constraints, and writing topic. Results revealed no group by time interaction effects for any outcomes. Moderation analyses showed that 1) low alexithymic women in the EWI group showed larger decreases in GP telephone calls over time than both high alexithymic women and controls and 2) women in the EWI group writing about their own cancer, but not women writing about other topics, showed a larger decrease than controls. The results from this large randomized trial are concordant with previous findings showing that EWI is unlikely to be a generally applicable intervention to improve health-related outcomes in cancer patients and cancer survivors. However, written disclosure might have a beneficial impact for individuals who write about their own cancer, as well as for those low in alexithymia.

Psychological stress and breast cancer incidence: a systematic review

OBJECTIVE

Breast cancer is the world's leading cause of cancer mortality in women. Stress is an imminent risk factor with a documented negative impact on neuro-endocrine and immune system. Numerous epidemiological studies have investigated the link between stress and cancer, reporting contradictory results from no association to a close causal link. The impact of the topic and the lack of conclusion compelled this systematic review.

METHODS

A systematic review was carried out, including all literature studies from 1966 to 2016, investigating the relationship between stress and the occurrence of breast cancer. Of the 1813 articles identified in the PubMed/Medline database, 52 were eligible and included in the analysis.

RESULTS

A number of 17 retrospective, 20 limited prospective and 15 prospective studies were analyzed. The number of patients exceeded 29,000, for a total number of more than 700.000 women recruited from hospital, screening cohorts or population registers. We identified 26 positive articles linking personal traits, stressful events and breast cancer, 18 negative articles that did not confirm their hypothesis and 8 articles that could not be classified. Facing heterogeneity, all possible misguiding factors such as: study design, information gathering, stress type, moment of exposure, individual susceptibility and personality, were discussed independently.

CONCLUSIONS

Qualitative analysis of articles has revealed a possible association between stress and cancer, especially regarding stressful life events. In the absence of a meta-analysis and taking into account the methodological heterogeneity of the studies, the results are difficult to interpret and the role of chance is difficult to exclude.

Stimulatory effect of desipramine on lung metastases of adenocarcinoma MADB 106 in stress highly-sensitive and stress non-reactive rats

The effect of antidepressant drugs on tumor progress is very poorly recognized. The aim of the present study was to examine the effect of individual reactivity to stress and 24-day desipramine (DES) administration on the metastatic colonization of adenocarcinoma MADB 106 cells in the lungs of Wistar rats. Wistar rats were subjected to stress procedure according to the chronic mild stress (CMS) model of depression for two weeks and stress highly-sensitive (SHS) and stress non-reactive (SNR) rats were selected. SHS rats were more prone to cancer metastasis than SNR ones and chronic DES treatment further increased the number of lung metastases by 59% and 50% in comparison to vehicle-treated appropriate control rats. The increase in lung metastases was connected with DES-induced skew macrophage activity towards M2 functional phenotype in SHS and SNR rats. Moreover, during 24h after DES injection in healthy rats, the decreased number of TCD8⁺ and B cells in SHS and SNR rats as well as NK cell cytotoxic activity in SNR rats could be attributed to the lowered capacity to defend against cancer metastasis observed in chronic DES treated and tumor injected rats.

A role for B cells in facilitating defense against an NK cell-sensitive lung metastatic tumor is revealed by stress

Stressors impair immune defenses and pose risks among cancer patients. Natural Killer cells are not the sole immune defense against tumor development. Utilizing an NK-sensitive tumor model, this study evaluated immune effects to stress and determined whether lung metastasis resulted from B cells' inability to augment tumorlytic function. Lung metastasis directly correlated with delayed lung B cell accumulation compared to NK, and T cells. Decreased interleukin-12 cytokine and CD80⁺ molecule expression by B cells correlated with decreased tumor lysis and increased tumor development. Thus, tumor defenses in the lung given stress exposure can depend on the B cell function.

Evaluation of intrapsychic processes, anxiety, and depression in postmenopausal women affected by breast cancer: a case-control study

BACKGROUND

The study of intrapsychic modalities can help to understand the association between depression and breast cancer patients and what kind of intervention can be planned. There is evidence that breast cancer is associated with the development of depression. The study of intrapsychic modalities may explain this association. Therefore, we aimed at investigating the intrapsychic and interpersonal processes of the structure of personality, anxiety, and depression of postmenopause breast cancer women.

METHODS

All participants (n = 63) underwent the following tests: SASB questionnaire (Structural Analysis of Interpersonal Behavior), describing intrapsychic and interpersonal processes, validated on the basis of DSMIV, and the CDQ and ASQ questionnaires describing depression and anxiety. We compared two groups: breast cancer (n = 63) and a healthy control group of women without cancer (n = 83).

RESULTS

Patients with breast cancer presented medium to high levels of anxiety and depression and intrapsychic level showed that they had less autonomy in their choices with low acceptance of their own feelings and tendency to be depressed compared to the control group (Cl 1 autonomy F = 10.21, p < 0.05, Cl 2 autonomy and love F = 13.01, p < 0.001, Cl 3 love F = 10.50, p < 0.01, Cl 5 control F = 6.44, p < 0.05, Cl 6 control and hate F = 4.49, p < 0.05, ASQ F = 6.07, p < 0.05, and CDQ F = 6.24, p < 0.05).

CONCLUSIONS

Intrapsychic characteristics such as tendency to depression, inability to being in contact with their own feelings, may be linked to difficulties in facing treatment and their condition of illness. Knowledge of these modalities could allow to plan a psychotherapeutic and multidisciplinary intervention aimed at facing the different phases of medical treatment.

Self-reported psychological stress and the risk of breast cancer: a case-control study

The aim of this study was to examine the relationship between severe life events and breast cancer risk. This study was based on a case-control examination of 858 Polish invasive breast cancer cases and 1085 controls matched for age and place of residence. Data on life events, sociodemographic characteristic, reproductive factors, family history of breast cancer, current weight and height, and lifestyle habits were collected between January 2003 and May 2007 using a self-administered questionnaire. Odds ratios with 95% confidence intervals were estimated as the measure of the relationship between life event stress and breast cancer risk using unconditional logistic regression analyses. After adjustment for potential breast cancer risk factors, women with four to six individual major life events had 5.33 times higher risk for breast cancer, compared with those in the lowest quartile. Similarly, women with a lifetime life change score greater than 210 had about 5 times higher risk compared to women with corresponding scores in the range 0-70. Several life events (death of a close family member, personal injury or illness, imprisonment/trouble with the law, retirement) were significantly associated with breast cancer risk. These findings suggest that major life events can play an important role in the etiology of breast cancer.

Stress and breast cancer: from epidemiology to molecular biology

Stress exposure has been proposed to contribute to the etiology of breast cancer. However, the validity of this assertion and the possible mechanisms involved are not well established. Epidemiologic studies differ in their assessment of the relative contribution of stress to breast cancer risk, while physiological studies propose a clear connection but lack the knowledge of intracellular pathways involved. The present review aims to consolidate the findings from different fields of research (including epidemiology, physiology, and molecular biology) in order to present a comprehensive picture of what we know to date about the role of stress in breast cancer development.

Personality Predictors of the Time Course for Lung Cancer Onset

Numerous findings suggest that personality is linked to the incidence and experience of negative health outcomes. More specifically, trait negative affect is negatively related to a number of health outcomes. The current study expands our understanding of the link between personality and disease by examining the time course for lung cancer onset. In a sample of patients who had recently undergone surgical resection for lung cancer, a variety of negative affect-related personality variables were assessed to determine their relationship with age at surgery. After controlling for smoking behavior, it was found that trait negative affect was associated with time course for lung cancer onset, such that those with higher (vs. lower) levels of trait negative affect manifested lung cancer earlier in their lives. Thus, trait negative affect represents an independent risk factor among those prone to lung cancer (i.e. smokers).

Breast cancer, psychological distress and life events among young women

Since 1983, studies have suggested an interaction between the severe life events, psychological distress and the etiology of Cancer. However, these associations are still under dispute.

The aim of the present study was to examine the relationship between life events, psychological distress and Breast Cancer (BC) among young women.

Do stress-related psychosocial factors contribute to cancer incidence and survival?

A substantial body of research has investigated the associations between stress-related psychosocial factors and cancer outcomes. Previous narrative reviews have been inconclusive. In this Review, we evaluated longitudinal associations between stress and cancer using meta-analytic methods. The results of 165 studies indicate that stress-related psychosocial factors are associated with higher cancer incidence in initially healthy populations (P = 0.005); in addition, poorer survival in patients with diagnosed cancer was noted in 330 studies (P <0.001), and higher cancer mortality was seen in 53 studies (P <0.001). Subgroup meta-analyses demonstrate that stressful life experiences are related to poorer cancer survival and higher mortality but not to an increased incidence. Stress-prone personality or unfavorable coping styles and negative emotional responses or poor quality of life were related to higher cancer incidence, poorer cancer survival and higher cancer mortality. Site-specific analyses indicate that psychosocial factors are associated with a higher incidence of lung cancer and poorer survival in patients with breast, lung, head and neck, hepatobiliary, and lymphoid or hematopoietic cancers. These analyses suggest that stress-related psychosocial factors have an adverse effect on cancer incidence and survival, although there is evidence of publication bias and results should be interpreted with caution.

Hydrocortisone down-regulates the tumor suppressor gene BRCA1 in mammary cells: a possible molecular link between stress and breast cancer

Psychological stress has been correlated with breast cancer development in numerous epidemiological studies. However, physiological and molecular models which may account for this association are not readily available. We have found that the stress hormone hydrocortisone (cortisol) down-regulates the expression of the breast cancer susceptibility gene BRCA1 in the nonmalignant mouse mammary cell line EPH4. This effect is concentration-dependent, is reliant on the continuous presence of hydrocortisone, and is not affected by the addition of lactogenic hormones, or growth conditions. Hydrocortisone was also found to negate a known positive effect of estrogen on BRCA1 expression and, therefore, may interfere with estrogen-related signaling in mammary epithelial cells. The repressive effect of hydrocortisone is diminished or lost in the mouse mammary lines HC-11 and SP1, respectively, suggesting regulation of the BRCA1 may differ between lines. We have uncovered two promoter regulatory sites, which are involved in BRCA1 regulation by hydrocortisone, namely the RIBS and UP regulatory elements. Binding of the transcription factor GABP to both sites is lost upon hydrocortisone addition, though the levels of these factors are not altered by hydrocortisone treatment. Because BRCA1 activity is important for a number of intracellular pathways involved in prevention of tumorigenesis, its observed down-regulation may represent a novel molecular mechanism for cortisol's involvement in breast cancer development.

Does Repression Exist? Memory, Pathogenic, Unconscious and Clinical Evidence

The current dispute regarding the existence of repression has mainly focused on whether people remember or forget trauma. Repression, however, is a multidimensional construct, which, in addition to the memory aspect, consists of pathogenic effects on adjustment and the unconscious. Accordingly, in order to arrive at a more accurate decision regarding the existence of repression, studies relevant to all three areas are reviewed. Moreover, since psychoanalysis regards repression as a key factor in accounting for the development and treatment of neurotic disorders, relevant research from these two domains are also taken into account. This comprehensive evaluation reveals little empirical justification for maintaining the psychoanalytic concept of repression.

Personality factors and breast cancer risk: a 13-year follow-up

Consistent scientific evidence on the possible relationship between psychologic variables and breast cancer development is lacking. In 1996, our group first reported on the present prospective, longitudinal study. We found a weak association between a high score on the antiemotionality scale (indicating an absence of emotional behavior or a lack of trust in one's own feelings) and the development of breast cancer. No associations were found between any of the other 10 studied personality traits and breast cancer development. However, the study had a relatively short follow-up and did not investigate interaction effects between various personality traits. Therefore, the current follow-up study was conducted with the same cohort, which included the 9705 women who attended a biennial population surveillance program for breast cancer and completed a self-report personality questionnaire between January 1, 1989, and December 31, 1990. Women who developed breast cancer during the period from May 17, 1995, through January 1, 2003, formed the case group (n = 217) and were compared with age-matched women without breast cancer who formed the control group (n = 868) with regard to personality traits and medical risk factors for breast cancer. None of the personality factors were statistically significantly associated with an increased risk of breast cancer, with or without adjusting for the medical risk factors. Also, the occurrence of a combination of various personality traits (eg, a so-called cancer-prone personality) was not related to breast cancer development.

Self-reported stress and risk of endometrial cancer: a prospective cohort study

OBJECTIVES

To assess a possible relationship between perceived stress and first-time incidence of primary endometrial cancer. Psychological stress may affect the synthesis and metabolism of estrogens and thereby be related to risk of endometrial cancer.

METHODS

The 6760 women participating in the Copenhagen City Heart Study were asked about their stress level at baseline from 1981 to 1983. These women were prospectively followed up in the Danish nationwide cancer registry until 2000 and <0.1% were lost to follow-up. Cox proportional hazard models were used to analyze data.

RESULTS

During follow-up, 72 women were diagnosed with endometrial cancer. For each increase in stress level on a 7-point stress scale, there was a lower risk of primary endometrial cancer (hazard ratio (HR) = 0.88; 95% confidence interval (CI), 0.76-1.01). This inverse association was particularly strong in women who received hormone therapy (HR = 0.77; 95% CI, 0.61-0.96) and in normal-weight women (HR = 0.73; 95% CI, 0.58-0.91).

CONCLUSIONS

Stress may affect gonadal synthesis of estrogens and alter the sensitivity of the uterus toward estrogen stimulation. These mechanisms may explain the lower risk of endometrial cancer observed among stressed women in this study. Despite these results, stress may still be a risk factor for a range of other diseases and should therefore not be considered a healthy response.

Psychological attitudes and risk of breast cancer in Japan: a prospective study

OBJECTIVE

To examine the association between psychological factors and the risk of breast cancer prospectively in a non-Western population.

METHODS

Data from the Japan Collaborative Cohort (JACC) study were analyzed. From 1988 to 1990, 34,497 women aged 40-79 years completed a questionnaire on medical, lifestyle and psychosocial factors. The rate ratios (RRs) of their responses were computed by fitting to proportional hazards models.

RESULTS

During the mean follow-up period of 7.5 years, 149 breast cancer cases were documented. Those individuals who possessed "ikigai" (Japanese term meaning something that made one's life worth living) showed a significantly lower risk of breast cancer (multivariate-adjusted RR=0.66; 95% confidence interval [CI]=0.47-0.94). Those who perceived themselves as able to make decisions quickly also had a lower risk of breast cancer (multivariate-adjusted RR=0.56; 95% CI=0.36-0.87). The other factors investigated, including ease of anger arousal and self-perceived stress of daily life were not associated with breast cancer risk.

CONCLUSIONS

Although further studies will be necessary to verify these findings, our results suggest that having "ikigai" and being decisive decrease an individual's subsequent risk of breast cancer.

Stress and breast cancer: a systematic update on the current knowledge

A vast body of research has been carried out to examine the relationship between psychological stress and the risk of breast cancer. Previous reviews on this issue have mainly focused on stressful life events and have included both prospective and retrospective studies. The results from these reviews have revealed conflicting data. We evaluate whether stressful life events, work-related stress, or perceived global stress are differentially associated with breast cancer incidence and breast cancer relapse in prospective studies. Systematic and explicit methods were used to identify, select, and critically appraise relevant studies. The substantial variability in the manner in which stress was conceptualized and measured did not allow for the calculation of a quantitative summary estimate for the association between stress and breast cancer. Despite the heterogeneity in the results obtained, it is concluded that stress does not seem to increase the risk of breast cancer incidence. Whether stress affects the progression of breast cancer is still unclear. Studies with more thorough adjustment for confounding factors and larger studies on stress and breast cancer relapse are required to address this issue.

Chemopreventive efficacy and anti-lipid peroxidative potential of Jasminum grandiflorum Linn. on 7,12-dimethylbenz(a)anthracene-induced rat mammary carcinogenesis

The aim of this study was to investigate the chemopreventive efficacy and anti-lipid peroxidative potential of Jasminum grandiflorum Linn. on 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary carcinogenesis. Mammary tumors were developed by a single subcutaneous injection of 25 mg DMBA in 1 mL emulsion of sunflower oil and physiological saline. The tumor incidence and tumor volume that formed in the breast were determined. Oral administration of ethanolic extract of J. grandiflorum flowers (JgEt) at a dose of 300 mg/kg body weight for 14 weeks to DMBA-injected animals completely prevented the formation of tumors in the pre-initiation period. JgEt also exerted significant anti-lipid peroxidative effect and improved the antioxidant defense system in DMBA-treated rats. The results of this study clearly indicate that JgEt has potent chemopreventive efficacy in experimental mammary carcinogenesis and further studies are warranted to isolate and characterize the bioactive principle from JgEt.

Depressive symptoms and prospective incidence of colorectal cancer in women

The authors examined depressive symptoms and prospective incidence of colorectal cancer and distal colorectal adenomas in 81,612 women without prior cancer from the Nurses' Health Study; 400 cases of colorectal cancer and 680 distal colorectal adenomas accrued between 1992 and the year 2000. Depressive symptoms were assessed in 1992 and 1996 with the five-question Mental Health Index (MHI-5), a subscale of the Short-Form 36 health status survey. Scores ranged from 0 to 100, and women with scores between 0 and 52 were defined as having significant depressive symptomatology. The authors also created four categories across the range of Mental Health Index scores: 0-52, 53-75, 76-85, and 86-100 (referent). Cox proportional hazards models were used to analyze the extent of depressive symptoms and colorectal events. Analyses were stratified by body mass index. In multivariate analyses with updated exposure, women with the highest levels of depressive symptoms had an elevated risk of incident colorectal cancer (hazard ratio = 1.43, 95% confidence interval: 0.97, 2.11) compared with women with the lowest levels of symptoms (p(trend) = 0.04). Associations appeared stronger in overweight women. However, depressive symptoms were unrelated to risk of colorectal adenomas. Associations are consistent with a possible role in late promotion of the disease.

Meta-analysis of the effects of psychosocial interventions on survival time in cancer patients

OBJECTIVE

To provide a quantitative summary of effects of psychosocial interventions on cancer survival, and to present an overview of methodological and reporting aspects of the studies.

METHOD

Electronic searches and manual searches of reference lists from review articles and retrieved papers. Two coders independently coded study, participant, treatment, and outcome characteristics of the studies meeting selection criteria.

RESULTS

Thirteen journal articles published between 1989 and 2003 reporting results from 14 controlled intervention studies were included. Results are based on data obtained from 2626 subjects. Effect sizes [hazard ratios (HR)] were heterogeneous and random effects models were used in the analyses. The total mean inverse-variance-weighted HR was 0.85 (95% CI: 0.65-1.11). Randomized studies (n=8) showed no overall treatment effect (HR: 0.77, 95% CI: 0.56-1.06), neither did the nonrandomized studies (HR: 1.00, 95% CI: 0.61-1.62). Interventions using individual treatment (n=3) were, however, found to be effective (HR: 0.55, 95% CI: 0.43-0.70) but interventions using group treatment (n=9) were ineffective (HR: 0.97, 95% CI: 0.73-1.27). Group treatments of breast cancer (n=6) were ineffective (HR: 0.95, 95% CI: 0.69-1.31).

CONCLUSION

A definite conclusion about whether psychosocial interventions prolong cancer survival seems premature. Future studies should use randomization to avoid self-selection of patients with poor prognosis. Interventions should focus on a single diagnosis, take into account known risk factors, and describe their interventions thoroughly.

Psychological factors and cancer development: Evidence after 30 years of research

The question whether psychological factors affect cancer development has intrigued both researchers and patients. This review critically summarizes the findings of studies that have tried to answer this question in the past 30 years. Earlier reviews, including meta-analyses, covered only a limited number of studies, and included studies with a questionable design (group-comparison, cross-sectional or semiprospective design). This review comprises only longitudinal, truly prospective studies (N=70). It was concluded that there is not any psychological factor for which an influence on cancer development has been convincingly demonstrated in a series of studies. Only in terms of 'an influence that cannot be totally dismissed,' some factors emerged as 'most promising': helplessness and repression seemed to contribute to an unfavorable prognosis, while denial/minimizing seemed to be associated with a favorable prognosis. Some, but even less convincing evidence, was found that having experienced loss events, a low level of social support, and chronic depression predict an unfavorable prognosis. The influences of life events (other than loss events), negative emotional states, fighting spirit, stoic acceptance/fatalism, active coping, personality factors, and locus of control are minor or absent. A methodological shortcoming is not to have investigated the interactive effect of psychological factors, demographic, and biomedical risk factors.

Hypericum perforatum methanolic extract inhibits growth of human prostatic carcinoma cell line orthotopically implanted in nude mice

The antiproliferative effect of serotonin-reuptake inhibitors (SSRI) and serotonin antagonists has been demonstrated in prostate tumors. Since Hypericum perforatum components act as serotonin-reuptake inhibitors and exert cytotoxic effects on several human cancer cell lines, in this work we analyzed the effect of a treatment with Hypericum perforatum extract (HPE) on the growth of human prostate cancer cells in vitro and in vivo. This study highlighted a significant reduction of tumor growth and number of metastasis suggesting that this natural compound may be useful in the treatment of prostate cancer.