Opioid Dose and Survival of Patients with Incurable Nonsmall Cell Lung Cancer: A Prospective Cohort Study

Benefits, Harms, and Stakeholder Perspectives Regarding Opioid Therapy for Pain in Individuals With Metastatic Cancer: Protocol for a Descriptive Cohort Study

BACKGROUND

Opioids are a key component of pain management among patients with metastatic cancer pain. However, the evidence base available to guide opioid-related decision-making in individuals with advanced cancer is limited. Patients with advanced cancer or cancer that is unlikely to be cured frequently experience pain. Opioids are a key component of pain management among patients with metastatic cancer pain. Many individuals with advanced cancer are now living long enough to experience opioid-related harm. Emerging evidence from chronic noncancer pain literature suggests that longer-term opioid therapy may have limited benefits for pain and function, and opioid-related harms are also a major concern. However, whether these benefits and harms of opioids apply to patients with cancer-related pain is unknown.

OBJECTIVE

This manuscript outlines the protocol for the "Opioid Therapy for Pain in Individuals With Metastatic Cancer: The Benefits, Harms, and Stakeholder Perspectives (BEST) Study." The study aims to better understand opioid decision-making in patients with advanced cancer, along with opioid benefits and harms, through prospective examination of patients' pain experiences and opioid side effects and understanding the decision-making by patients, care partners, and clinicians.

METHODS

This is a multicenter, prospective cohort study that aims to enroll 630 patients with advanced cancer, 20 care partners, and 20 clinicians (670 total participants). Patient participants must have an advanced solid cancer diagnosis, defined by the American Cancer Society as cancer that is unlikely to be cured. We will recruit patient participants within 12 weeks after diagnosis so that we can understand opioid benefits, harms, and perspectives on opioid decision-making throughout the course of their advanced cancer (up to 2 years). We will also specifically elicit information regarding long-term opioid use (ie, opioids for ≥90 consecutive days) and exclude patients on long-term opioid therapy before an advanced cancer diagnosis. Lived-experience perspectives related to opioid use in those with advanced cancer will be captured by qualitative interviews with a subset of patients, clinicians, and care partners. Our data collection will be grounded in a behavioral decision research approach that will allow us to develop future interventions to inform opioid-related decision-making for patients with metastatic cancer.

RESULTS

Data collection began in October 2022 and is anticipated to end by November 2024.

CONCLUSIONS

Upon successful execution of our study protocol, we anticipate the development of a comprehensive evidence base on opioid therapy in individuals with advanced cancer guided by the behavioral decision research framework. The information gained from this study will be used to guide interventions to facilitate opioid decisions among patients, clinicians, and care partners. Given the limited evidence base about opioid therapy in people with cancer, we envision this study will have significant real-world implications for cancer-related pain management and opioid-related clinical decision-making.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/54953.

A novel investigation into the negative impact of opioid use on the efficacy of immune checkpoint inhibitors in advanced non-small cell lung cancer patients

OBJECTIVE

Immune checkpoint inhibitors (ICIs) have effectively improved the clinical outcome of advanced non-small cell lung cancer (NSCLC). Opioids are commonly used for pain relief in cancer patients. This study aims to clarify the prognostic impact of opioid use in advanced NSCLC patients receiving ICI therapy.

METHODS

A systematic literature review was carried out using online databases before July 2023. The meta-analysis was used to clarify the correlation of opioid use with the overall survival (OS) or progression-free survival (PFS) of ICI-treated NSCLC patients, both of which were determined using hazard ratios (HRs) coupled with 95 % confidence intervals (CIs). Then, an independent cohort enrolling 181 NSCLC patients was utilized for validation. Finally, a comprehensive bioinformatics analysis based on TCGA cohort was performed to investigate the prognostic significance of opioid target genes (OTGs) and their correlation with immune infiltration in NSCLC patients.

RESULTS

A total of 8 studies enrolling 1174 patients were included in the meta-analysis. Opioid use was negatively associated with worse PFS (HR = 2.16, 95 %CI: 1.26-3.71) and OS (HR = 2.02, 95 %CI: 1.54-2.63) in ICI-treated NSCLC patients. The retrospective validation confirmed the above result and identified opioid use as an independent unfavorable predictor for PFS and OS in both the entire cohort and ICI subgroup. The bioinformatic analysis identified 14 prognostic OTGs (CYP17A1, PDYN, PYCARD, FGA, NTSR1, FABP1, HPCA, PENK, PDGFB, LIN7A, FKBP5, TYMS, CACNA1H and LDHA), most of which were correlated with immune infiltration in NSCLC. A risk model was constructed based on 14 OTGs and found to effectively stratify the clinical outcome in both the training and validation set, independent of age, gender and TNM staging system. The model was also significantly correlated with infiltration of activated dendritic cells, neutrophils and tumor infiltrating lymphocytes. Finally, a nomogram was constructed based on the model, age, gender and TNM stage, which could predict well the 1-, 3- and 5-year survival of NSCLC patients.

CONCLUSION

Opioid use is correlated with the poor clinical outcome in ICI-treated NSCLC patients. Precise pain management is highly advocated and opioids are recommended to be cautiously used in these patients. OTGs have the potential to be prognostic biomarkers for NSCLC patients and their role in tumor immunity needs to be further investigated.

Impact of Opioid Use on Duration of Therapy and Overall Survival for Patients with Advanced Non-Small Cell Lung Cancer Treated with Immune Checkpoint Inhibitors

Immune checkpoint inhibitors (ICI) have significantly improved outcomes in advanced non-small cell lung cancer (NSCLC). We evaluated the effect of opioid use on outcomes in patients receiving ICI either alone or with chemotherapy. We conducted a retrospective review of 209 patients with advanced NSCLC who received an ICI at the University of Virginia between 1 February 2015 and 1 January 2020. We performed univariate and multivariate analyses to evaluate the impact of opioid use on duration of therapy (DOT) and overall survival (OS). Patients with no or low opioid use (n = 172) had a median DOT of 12.2 months (95% CI: 6.9-17.4) compared to 1.9 months (95% CI: 1.8-2.0) for those with high opioid use (n = 37, HR 0.26 95% CI: 0.17-0.40, p < 0.001). Patients with no or low opioid use had a median OS of 22.6 months (95% CI: 14.8-30.4) compared to 3.8 months (95% CI: 2.7-4.9) for those with high opioid use (HR 0.26 95% CI: 0.17-0.40 p < 0.001). High opioid use was associated with a shorter DOT and worse OS. This difference remained significant when accounting for possible confounding variables. These data warrant investigation of possible mechanistic interactions between opioids, tumor progression, and ICIs, as well as prospective evaluation of opioid-sparing pain management strategies, where possible.

Long-term opioid therapy trajectories and overdose in patients with and without cancer

Objective

Pain is experienced by most patients with cancer and opioids are a cornerstone of management. Our objectives were (1) to identify patterns or trajectories of long-term opioid therapy (LTOT) and their correlates among patients with and without cancer and (2) to assess the association between trajectories and risk for opioid overdose, considering the potential moderating role of cancer.

Methods and Analysis

We conducted a retrospective cohort study among individuals in the US Veterans Health Administration (VHA) database with incident LTOT with and without cancer (N=44,351; N=285,772, respectively) between 2010-2017. We investigated the relationship between LTOT trajectory and all International Classification of Diseases-9 and 10-defined accidental and intentional opioid-related overdoses.

Results

Trajectories of opioid receipt observed in patients without cancer and replicated in patients with cancer were: low-dose/stable trend, low-dose/de-escalating trend, moderate-dose/stable trend, moderate-dose/escalating with quadratic downturn trend, and high-dose/escalating with quadratic downturn trend. Time to first overdose was significantly predicted by higher-dose and escalating trajectories; the two low-dose trajectories conferred similar, lower risk. Conditional hazard ratios (99% CI) for the moderate-dose, moderate-dose/escalating with quadratic downturn and high-dose/escalating with quadratic downturn trends were 1·84 (1·18, 2·85), 2·56 (1·54, 4·25), and 2·41 (1·37, 4·26), respectively. Effects of trajectories on time to overdose did not differ by presence of cancer; inferences were replicated when restricting to patients with stage 3/4 cancer.

Conclusion

Patients with cancer face opioid overdose risks like patients without cancer. Future studies should seek to expand and address our knowledge about opioid risk in cancer patients.

Trial registration

None.

Effects of Opioids on Immune and Endocrine Function in Patients with Cancer Pain

OPINION STATEMENT

Opioids are an important treatment in managing cancer pain. Uncontrolled pain can be detrimental to function and quality of life. Common adverse effects of opioids such as sedation, constipation and nausea are well recognised, but opioid effects on the endocrine and immune systems are less apparent. The evidence for the immunomodulatory effects of opioids suggest that some opioids might be immunosuppressive and that their use might be associated with reduced survival and increased rates of infection in patients with cancer. However, the quality of this evidence is limited. Opioid-induced endocrinopathies, in particular opioid-induced hypogonadism, may also impact cancer survival and impair quality of life. But again, evidence in patients with cancer is limited, especially with regard to their management. There are some data that different opioids influence immune and endocrine function with varying outcomes. For example, some opioids, such as tramadol and buprenorphine, demonstrate immune-sparing qualities when compared to others. However, most of this data is preclinical and without adequate clinical correlation; thus, no opioid can currently be recommended over another in this context. Higher opioid doses might have more effect on immune and endocrine function. Ultimately, it is prudent to use the lowest effective dose to control the cancer pain. Clinical presentations of opioid-induced endocrinopathies should be considered in patients with cancer and assessed for, particularly in long-term opioid users. Hormone replacement therapies may be considered where appropriate with support from endocrinology specialists.

Survival Outcomes Associated With the Size of Opioid Prescriptions in the Management of Chronic Pain Related to Advanced Nasopharyngeal Carcinoma

OBJECTIVE

Patients with advanced nasopharyngeal carcinoma (ANC) often experience chronic pain. Opioids are generally recommended to treat tumor-related pain, but increased opioid use may lead to detrimental aftereffects, particularly with respect to tumor progression, resulting in reduced quality of life and increased risk of death. Our objective was to investigate whether the high size of opioid prescriptions is associated with poor overall survival (OS) in patients with ANC.

METHODS

A consecutive cohort of patients with newly diagnosed ANC who underwent high or low opioid prescription size treatment during 2012-2019 was retrospectively identified from our medical institutions. Survival was estimated with the Kaplan-Meier method with a log-rank test. Multivariate binary logistic regression was used to assess the association between opioid use and OS, adjusting for age, sex, body mass index (BMI), Eastern Collaborative Oncology Group performance status (ECOG PS), and ANC histology. The criterion to distinguish between the high opioid prescription size group [HD] and the low opioid prescription size group [LD] was 5 mg of oral morphine equivalents (OME) per 24 hours.

RESULTS

The cohort consisted of 244 consecutive patients (HD: n = 120, median age = 66 years [range, 40-81 years]; LD: n = 124, median age = 65 years [40-82 years]. Patients who underwent treatment with a high opioid prescription size had a worse median OS than those who underwent treatment with a low opioid prescription size (5.1 vs 6.6 months), and the high opioid prescription size was associated with a remarkable 48% higher risk of death than the low opioid prescription size (HR 1.48, 95% CI 1.11-1.98; P = .005). The cumulative dose of opioids greater than or equal to 500 mg of OME was associated with a higher risk of death, adjusted for age, sex, BMI, ECOG PS, and ANC histology.

CONCLUSIONS

In patients with newly diagnosed ANC experiencing palliative care, a high opioid prescription size may be associated with shorter OS than a low opioid prescription size.

Effect of Opioids on Survival in Patients with Cancer

Opioids are commonly used for pain management in patients with cancer. They have a range of unwanted effects, including some that potentially influence cancer growth. This article reviews the data assessing the effects of opioids on survival in patients with cancer. Many studies assessing this show an association between opioids and decreased survival. This effect is present even at very low doses of opioids. These studies do not assess causality, so it is not known if it is a direct effect of opioids on survival. As the control groups are not matched to the opioid group it might be that opioids are being used to control pain and patients receiving opioids have more aggressive cancers and it is the underlying cancer which is causing the decreased survival. Furthermore, although some studies allude to different opioids having different effects on survival, often all opioids are pooled in analysis. Future work needs to try to ascertain causality and differentiate between different opioids, pain, and cancer-mediated effects on survival in specific cancer types. Until then, opioids should continue to be used in patients with cancer as part of measures to optimise comfort and quality of life.

Less Well-Known Consequences of the Long-Term Use of Opioid Analgesics: A Comprehensive Literature Review

BACKGROUND

The adverse effects of short-term opioid analgesics are well known and acknowledged; however, the spectrum of the sequelae of long-term use seems less clear. Some effects may remain undetected but still have the potential to cause harm and reduce patients' quality of life.

OBJECTIVE

To review the literature on the adverse effects of long-term opioid therapy.

METHODS

We performed a quasi-systematic search, analyzing articles published in the MEDLINE database between January 2000 and March 2021 that identified adverse effects of opioids used for chronic pain treatment.

RESULTS

Growing evidence indicates that there are multiple serious adverse effects of opioid treatment. Long-term opioid use may have significant effects on the endocrine, immune, cardiovascular, respiratory, gastrointestinal, and neural systems. Studies show that long-term opioid treatment increases the risk of fractures, infections, cardiovascular complications, sleep-disordered breathing, bowel dysfunction, overdose, and mortality. Opioids may potentially affect cancer development. Most consequences of the long-term use of opioids have been identified in studies of patients with non-malignant pain.

CONCLUSION

Studies indicate that long-term use of opioids increases the risk of drug-related events in a significant number of patients. Clinicians should be aware of these complications associated with prescribing opioids, discuss them with patients, prevent complications, if possible, and diagnose them early and manage adequately. More human studies are needed to assess the risk, including trials with individual opioids, because they have different adverse effect profiles.

Opioids in cancer: The κ‑opioid receptor (Review)

The κ‑opioid receptor (KOR) is one of the primary receptors of opioids and serves a vital role in the regulation of pain, anesthesia, addiction and other pathological and physiological processes. KOR is associated with several types of cancer and may influence cancer progression. It has been proposed that KOR may represent a new tumor molecular marker and provide a novel basis for molecular targeted therapies for cancer. However, the association between KOR and cancer remains to be explored comprehensively. The present review introduces KOR and its association with different types of cancer. Improved understanding of KOR may facilitate development of novel antitumor therapies.

The association between gut microbiome affecting concomitant medication and the effectiveness of immunotherapy in patients with stage IV NSCLC

Several observational studies suggested that gut microbiome-affecting-medication impairs the effectiveness of immunotherapy in patients with metastatic non-small-cell lung cancer (NSCLC). We postulated that if the effectiveness of immunotherapy is affected by drug-related changes of the microbiome, a stronger association between the use of co-medication and overall survival (OS) will be observed in patients treated with immunotherapy as compared to patients treated with chemotherapy. In a retrospective matched cohort study, immunotherapy patients were matched (1:1) to patients treated with chemotherapy in the pre immunotherapy era. The association between the use of antibiotics, opioids, proton pump inhibitors, metformin and other antidiabetics on OS was assessed with multivariable cox-regression analyses. Interaction tests were applied to investigate whether the association differs between patients treated with immuno- or chemotherapy. A total of 442 patients were studied. The use of antibiotics was associated with worse OS (adjusted Hazard Ratio (aHR) 1.39, p = 0.02) independent of the type of therapy (chemotherapy or immunotherapy). The use of opioids was also associated with worse OS (aHR 1.33, p = 0.01). The other drugs studied showed no association with OS. Interaction term testing showed no effect modification by immuno- or chemotherapy for the association of antibiotics and opioids with OS. The use of antibiotics and opioids is similarly associated with worse outcomes in both chemotherapy and immunotherapy treated NSCLC patients. This suggests that the association is likely to be a consequence of confounding rather than disturbing the composition of the microbiome.

Targeting the mu-Opioid Receptor for Cancer Treatment

PURPOSE OF REVIEW

Opioids are still the most effective and widely used treatments for acute and chronic pain in cancer patients. This review focuses on the impact of opioids and mu-opioid receptors (MOR) on tumor progression and providing new ideas for targeting the MOR in cancer treatment.

RECENT FINDINGS

Studies estimated that opioids facilitate tumor progression and are related to the worse prognosis in cancer patients. As the primary receptor of opioids, MOR is involved in the regulation of malignant transformation of tumors and participating in proliferation, invasion, metastasis, and angiogenesis. MOR may be a new molecular marker of malignant tumors and thus become a new target for cancer therapy, which may be beneficial to the outcomes of cancer patients.

Concomitant use of analgesics and immune checkpoint inhibitors in non-small cell lung cancer: A pharmacodynamics perspective

The invention of immunotherapy, such as immune checkpoint inhibitors (ICIs) for advanced-stage non-small cell lung cancer (NSCLC), has become a new standard of care for a defined group of NSCLC patients. However, the possible impacts of ICI interactions with analgesics for alleviating cancer-related pain are unclear and lack clinical evidence. Many studies have indicated that opioids detrimentally affect the immune system, possibly harming patients of ongoing immunotherapy. Opioids may repress the immune system in various ways, including impairing T cell function, upregulating immunosuppressor Treg cells, and interrupting intestinal microflora composition that disrupts the entire immune system. Furthermore, opioids can influence tumor progression and metastasis directly as opioid receptors are overexpressed in several types of NSCLC. In contrast, another analgesic acting on cyclooxygenase (COX) inhibition (i.e., NSAIDs) may be a candidate for adjuvant therapy since COX-2 is also expressed in the tumor cells of NSCLC patients. In addition, COX-2 is associated with tumor proliferation and metastasis. Therefore, both prospective and retrospective studies should confirm the advantages and disadvantages of the concurrent use of analgesics and ICIs in a clinical setting.

Forty-two Million Ways to Describe Pain: Topic Modeling of 200,000 PubMed Pain-Related Abstracts Using Natural Language Processing and Deep Learning-Based Text Generation

OBJECTIVE

Recent efforts to update the definitions and taxonomic structure of concepts related to pain have revealed opportunities to better quantify topics of existing pain research subject areas.

METHODS

Here, we apply basic natural language processing (NLP) analyses on a corpus of >200,000 abstracts published on PubMed under the medical subject heading (MeSH) of "pain" to quantify the topics, content, and themes on pain-related research dating back to the 1940s.

RESULTS

The most common stemmed terms included "pain" (601,122 occurrences), "patient" (508,064 occurrences), and "studi-" (208,839 occurrences). Contrarily, terms with the highest term frequency-inverse document frequency included "tmd" (6.21), "qol" (6.01), and "endometriosis" (5.94). Using the vector-embedded model of term definitions available via the "word2vec" technique, the most similar terms to "pain" included "discomfort," "symptom," and "pain-related." For the term "acute," the most similar terms in the word2vec vector space included "nonspecific," "vaso-occlusive," and "subacute"; for the term "chronic," the most similar terms included "persistent," "longstanding," and "long-standing." Topic modeling via Latent Dirichlet analysis identified peak coherence (0.49) at 40 topics. Network analysis of these topic models identified three topics that were outliers from the core cluster, two of which pertained to women's health and obstetrics and were closely connected to one another, yet considered distant from the third outlier pertaining to age. A deep learning-based gated recurrent units abstract generation model successfully synthesized several unique abstracts with varying levels of believability, with special attention and some confusion at lower temperatures to the roles of placebo in randomized controlled trials.

CONCLUSIONS

Quantitative NLP models of published abstracts pertaining to pain may point to trends and gaps within pain research communities.

Opioids and cancer prognosis: A summary of the clinical evidence

Pain is a common and devastating symptom among cancer patients. It can be caused by the cancer itself or by certain therapies like surgery, radiation or chemotherapy. Opioids are the first line of treatment for moderate to severe cancer-related pain. Opioids alone or in combination with non-opioid analgesics and adjuvant medications are important components for pain management during the perioperative period for cancer patients. Opioids act on the μ-opioid receptor (MOR), which is expressed in cancer cells and non-malignant cells of the tumor microenvironment. Retrospective studies suggest an association between the expression of MOR in cancers and shorter survival. In addition, recent evidence suggests that opium use and prescription opioids can influence clinical oncological outcomes. In this review, we will summarize the clinical evidence regarding the effect of opioid administration and survival in patients with cancer as well as the current evidence involving MOR expression and cancer progression.

Endogenous Opiates and Behavior: 2018

This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).

Polypharmacy among older advanced lung cancer patients taking EGFR tyrosine kinase inhibitors

OBJECTIVE

Polypharmacy (PP) is a common problem among the older adults and has a potential effect on health-related problems. However, the significance of PP in older advanced non-small cell lung cancer (NSCLC) patients and those on oral molecular-targeted anticancer agents is unclear.

MATERIALS AND METHODS

This retrospective, nonrandomized study reviewed the records of 334 advanced NSCLC patients who underwent epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment. PP was defined as ≥ 5 concomitant medications. Potentially inappropriate medication (PIM) use was measured using the updated screening tool of older people's prescriptions (STOPP) ver. 2 criteria. We also estimated survival distributions using the Kaplan-Meier method, compared between-group differences using the log-rank test, explored potential predictors of survival using Cox regression, and performed cluster analysis to identify factors affecting multiple-medication use.

RESULTS

The PP and PIM use prevalence was 38.4% and 31.9%, respectively. The median overall survival (OS) for PP(+) and PP(-) patients was 19.4 and 27.3 months, respectively. Multivariate analysis revealed a significant correlation between PP and OS. The frequency of unexpected hospitalization during EGFR-TKI treatment was higher in PP(+) patients compared to PP(-) patients (49.4% vs. 29.4%; odds ratio = 2.34).

CONCLUSION

PP is an independent prognostic factor in older advanced NSCLC patients taking EGFR-TKIs. PP can be used as a simple indicator of such patients' comorbidities and symptoms or as a predictive marker of unexpected hospitalization during treatment.

Opioids and Cancer Mortality

OPINION STATEMENT

Opioids are the gold standard for the treatment of cancer-related pain. Preclinical studies have associated opioids with cancer progression and overall survival. In mice models, opioids have been shown to possess pro-tumor activity secondary to immunosuppression, migration of tumor cells, increased activity of vascular endothelial growth factor receptors, and angiogenesis leading to tumor progression. In contrast, opioids have also been associated with having antitumor activity by activation of apoptosis and phagocytosis. However, high-quality randomized controlled trials in humans that are focused on the association between opioids and survival in cancer patients are lacking, which underscores the importance of being cautious when interpreting the results of the preclinical studies. Cancer-related pain is complex and multifactorial and may worsen as the disease progresses leading to higher opioid utilization. Moreover, cancer pain by itself has been associated with poor survival. The survival in these advanced cancer patients taking opioids may be more likely to be associated with cancer progression and not the opioid use. Adequate treatment of cancer pain has the potential to improve quality of life and performance status, highlighting the importance of continuing to use opioids to manage pain efficiently. More research is clearly needed.

The impact of pain and opioids use on survival in cancer patients: Results from a population-based cohort study and a meta-analysis

The study aimed to explore whether cancer-related pain and opioids use are associated with the survival of cancer patients, and perform a cohort study and a meta-analysis to quantify the magnitude of any association.A retrospective cohort study was performed to analyze the impact of pain level, and opioids use on cancer-specific survival (CSS) in advanced cancer patients. Patients and relevant medical records were selected from the registry of the Radiation and chemotherapy division of Ningbo First Hospital between June 2013 and October 2017. Hazard ratios (HRs) and 95% confidential intervals (CIs) for CSS by opioids use were calculated by univariate and multivariate Cox regression analyses. The systematic review included relevant studies published before October 2018. The combined HRs and 95% CIs for overall survival (OS) and progression-free survival (PFS) were calculated using random-effect models.A total of consecutive 203 cancer patients were included in the cohort study. Kaplan-Meier curves indicate a negative association between CSS and cancer-related pain or opioids requirement, but less evidence of an association with the dose of opioids use. Multivariate models revealed that the pain level and opioids requirement were associated with shorter CSS, after adjusting for significant covariates. The results of the meta-analysis indicated that postoperative opioids use had a poor effect on PFS, and opioids use for cancer-related pain was associated with poor OS in cancer patients, while intraoperative opioids use was not associated with cancer survival.We concluded that cancer-related pain and opioids requirements are associated with poor survival in advanced cancer patients, and postoperative opioids use and opioids use for cancer-related pain may have an adverse effect on the survival of cancer patients.

Opioids in Cancer Development, Progression and Metastasis: Focus on Colorectal Cancer

OPINION STATEMENT

So far, opioids have been successfully used to reduce cancer pain in patients in order to improve their quality of life. However, the use of opioids leads to numerous side effects such as constipation, drowsiness, nausea, itching, increased sweating and hormonal changes. In this review, we described the action of opioids in several molecular pathways significant for maintenance of the intestinal homeostasis including the impact on the intestinal epithelium integrity, changes in microbiome composition, modulation of the immune system or induction of apoptosis and inhibition of angiogenesis. We summed up the role of individual opioids in the processes involved in the growth and development of cancer and elucidated if targeting opioid receptors may constitute novel therapeutic option in colon cancer.

The relationship between pain, analgesics and survival in patients with advanced cancer; a secondary data analysis of the international European palliative care Cancer symptom study

PURPOSE

Opioids reduce cancer-related pain but an association with shorter survival is variably reported.

AIM

To investigate the relationship between pain, analgesics, cancer and survival within the European Palliative Care Cancer Symptom (EPCCS) study to help inform clinical decision making.

METHODS

Secondary analysis of the international prospective, longitudinal EPCCS study which included 1739 adults with advanced, incurable cancer receiving palliative care. In this secondary analysis, for all participants with date of death or last follow up, a multilevel Weibull survival analysis examined whether pain, analgesics, and other relevant variables are associated with time to death.

RESULTS

Date of death or last follow-up was available for 1404 patients (mean age 65.7 [SD:12.3];men 50%). Secondary analysis of this group showed the mean survival from baseline was 46.5 (SD:1.5) weeks (95% CI:43.6-49.3). Pain was reported by 76%; 60% were taking opioids, 51% non-opioid analgesics and 24% co-analgesics. Opioid-use was associated with decreased survival in the multivariable model (HR = 1.59 (95% CI:1.38-1.84), p < 0.001). An exploratory subgroup analysis of those with C-reactive protein (CRP) measures (n = 219) indicated higher CRP was associated with poorer survival (p = 0.001). In this model, the strength of relationship between survival and opioid-use weakened (p = 0.029).

CONCLUSION

Opioid-use and survival were associated; this relationship weakened in a small sensitivity-testing subgroup analysis adjusting for CRP. Thus, the observed relationship between survival and opioid-use may partly be due to tumour-related inflammation. Larger studies, measuring disease activity, are needed to confirm this finding to more accurately judge the benefits and risks of opioids in advanced progressive disease.