The role of patient, tumour and system factors in socioeconomic inequalities in lung cancer treatment: population-based study

Socioeconomic Inequalities in Novel NSCLC Treatments During the Era of Tumor Biomarker-Guided Therapy: A Population-Based Cohort Study in a Publicly Funded Health Care System

INTRODUCTION

Socioeconomic inequalities in the utilization of conventional NSCLC treatments are well documented. Nevertheless, it is not known whether these inequalities are also observed with novel anticancer therapies. This study evaluated associations between deprivation and utilization of novel anticancer therapies targeting tumor biology, the immune system, or both, within the English national publicly funded health care system.

METHODS

A retrospective analysis of 90,785 patients diagnosed with having a histologically confirmed stage IV NSCLC from January 1, 2012, to December 31, 2017, sourced from the English national population-based cancer registry and linked Systemic Anti-Cancer Therapy database, was undertaken. Multivariable logistic regression evaluated the likelihood of novel anticancer therapy utilization by deprivation category of area of residence at diagnosis (measured by quintiles of the income domain of the index of multiple deprivation).

RESULTS

Multivariable analyses revealed marked treatment inequalities by deprivation. Patients residing in the most deprived areas were more than half as likely to use any novel therapy (multivariable OR [mvOR] = 0.45, 95% confidence interval [CI]: 0.41-0.49) compared with patients residing in the most affluent areas. Deprivation associations with treatment utilization were slightly stronger with targeted treatments ([most versus least deprived] mvOR = 0.39, 95% CI: 0.35-0.43) than immune checkpoint inhibitors (mvOR = 0.58, 95% CI: 0.51-0.66).

CONCLUSIONS

There are marked socioeconomic inequalities in NSCLC novel treatment utilization, even in the English National Health Service where treatment is free at the point of delivery. These findings have important implications for equitable delivery of drugs, which have transformed outcomes in metastatic lung cancer. Further work exploring the underlying causes is now needed.

Breast Cancer Care Pathways for Women with Preexisting Severe Mental Disorders: Evidence of Disparities in France?

The excess cancer mortality in persons with severe mental illness (SMI) has been well documented, and research suggests that it may be influenced by care-related factors. Our objective was to assess breast cancer care pathways in women with SMI in France, using an exhaustive population-based data-linkage study with a matched case-control design. The cases were 1346 women with incident breast cancer in 2013/2014 and preexisting SMI who were matched with three controls without SMI presenting similar demographics, initial breast cancer type, and year of incidence. We compared cancer care pathways and their quality for cases and controls, using a consensual set of indicators covering diagnosis, treatment, follow-up, and mortality (until 2017). After adjusting for covariates, cases had lower odds to undergo the main diagnostic tests, lumpectomy, adjuvant chemotherapy, and radiotherapy, as well as hormone therapy, but higher odds for mastectomy. Suboptimal quality in cancer pathways was observed for both groups, but to a higher extent for cases, especially for not receiving timely care after diagnosis and post-treatment follow-up. Breast cancer mortality, considering competing risks of deaths, was significantly elevated in women with SMI. These findings highlight disparities in cancer care pathways for individuals with SMI, as well as specific aspects of the care continuum which could benefit from targeted actions to reach equity of outcomes.

Surgical under-treatment of older adult patients with cancer: A systematic review and meta-analysis

BACKGROUND

Older patients with cancer often have lower surgery rates and survival than younger patients, but this may reflect surgical contraindications of advanced disease, comorbidities, and frailty - and not necessarily under-treatment.

OBJECTIVES

This review aims to describe variations in surgery rates and observed or net survival among younger (<75) and older (≥75) patients with breast, lung and colorectal cancer, while taking account of pre-existing health factors, in order to understand how under-treatment is defined and estimated in the literature.

METHOD

MEDLINE, EMBASE, Web of Science and PubMed databases were searched for studies reporting surgery rates and observed or net survival among younger and older patients with breast, lung, and colorectal cancer. Study quality was assessed using the Newcastle Ottawa Scale, and random effects meta-analyses were used to combine study results. The I-squared statistic and subgroup analyses were used to assess heterogeneity.

RESULTS

Thirty relatively high-quality studies of patients with breast (230,200; 71.9%), lung (77,573; 24.2%), and colorectal (12,407; 3.9%) cancers were identified. Compared to younger patients, older patients were less likely to receive surgical treatment for 1) breast cancer after adjusting for comorbidity, performance status (PS), functional status and patient choice, 2) lung cancer after accounting for stage, comorbidity, PS, and 3) colorectal cancer after adjusting for stage, comorbidity, and gender. The pooled unadjusted analyses showed lower surgery receipt in older patients with breast (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.13-0.78), lung (OR 0.54, 95% CI 0.39-0.75), and colorectal (OR 0.59, 95% CI 0.51-0.68) cancer. In separate analyses, older patients with breast, lung and colorectal cancer had lower observed and net survival, compared to younger patients.

CONCLUSIONS

Lower surgery rates in older patients may contribute to their poorer survival compared to younger patients. Future research quantifying under-treatment should include necessary clinical factors, patient choice, patient's quality of life and a statistically-robust approach, which will demonstrate how much of the survival deficit in older patients is due to their receiving lower surgery rates.

Are socio-economic inequalities in breast cancer survival explained by peri-diagnostic factors?

BACKGROUND

Patients living in more deprived localities have lower cancer survival in England, but the role of individual health status at diagnosis and the utilisation of primary health care in explaining these differentials has not been widely considered. We set out to evaluate whether pre-existing individual health status at diagnosis and primary care consultation history (peri-diagnostic factors) could explain socio-economic differentials in survival amongst women diagnosed with breast cancer.

METHODS

We conducted a retrospective cohort study of women aged 15-99 years diagnosed in England using linked routine data. Ecologically-derived measures of income deprivation were combined with individually-linked data from the English National Cancer Registry, Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. Smoking status, alcohol consumption, BMI, comorbidity, and consultation histories were derived for all patients. Time to breast surgery was derived for women diagnosed after 2005. We estimated net survival and modelled the excess hazard ratio of breast cancer death using flexible parametric models. We accounted for missing data using multiple imputation.

RESULTS

Net survival was lower amongst more deprived women, with a single unit increase in deprivation quintile inferring a 4.4% (95% CI 1.4-8.8) increase in excess mortality. Peri-diagnostic co-variables varied by deprivation but did not explain the differentials in multivariable analyses.

CONCLUSIONS

These data show that socio-economic inequalities in survival cannot be explained by consultation history or by pre-existing individual health status, as measured in primary care. Differentials in the effectiveness of treatment, beyond those measuring the inclusion of breast surgery and the timing of surgery, should be considered as part of the wider effort to reduce inequalities in premature mortality.

A systematic review and meta-analysis of haematological malignancies in residents living near petrochemical facilities

BACKGROUND

The petrochemical industry is a major source of hazardous and toxic air pollutants that are recognised to have mutagenic and carcinogenic properties. A wealth of occupational epidemiology literature exists around the petrochemical industry, with adverse haematological effects identified in employees exposed to 'low' concentrations of aromatic hydrocarbons (benzene, toluene, ethylbenzene, and xylene). Releases from the petrochemical industry are also thought to increase the risk of cancer incidence in fenceline communities. However, this emerging and at times inconclusive evidence base remains fragmented. The present study's aim was to conduct a systematic review and meta-analysis of epidemiological studies investigating the association between incidences of haematological malignancy and residential exposure to the petrochemical industry.

METHODS

Epidemiological studies reporting the risk of haematological malignancies (Leukaemia, Hodgkin's lymphoma, Non-Hodgkin's lymphoma, and Multiple myeloma) were included where the following criteria were met: (i) Cancer incidence is diagnosed by a medical professional and coded in accordance to the International Classification of Diseases; (ii) A clear definition of fenceline communities is provided, indicating the proximity between exposed residents and petrochemical activities; and (iii) Exposure is representative of normal operating conditions, not emergency events. Two investigators independently extracted information on study characteristics and outcomes in accordance with PRISMA and MOOSE guidelines. Relative risks and their 95% confidence intervals were pooled across studies for the four categories of haematological malignancy, using a random effects meta-analysis.

RESULTS

The systematic review identified 16 unique studies, which collectively record the incidence of haematological malignancies across 187,585 residents living close to a petrochemical operation. Residents from fenceline communities, less than 5 km from a petrochemical facility (refinery or manufacturer of commercial chemicals), had a 30% higher risk of developing Leukaemia than residents from communities with no petrochemical activity. Meanwhile, the association between exposure and rarer forms of haematological malignancy remains uncertain, with further research required.

CONCLUSIONS

The risk of developing Leukaemia appears higher in individuals living near a petrochemical facility. This highlights the need for further policy to regulate the release of carcinogens by industry.

Association between age, deprivation and specific comorbid conditions and the receipt of major surgery in patients with non-small cell lung cancer in England: A population-based study

INTRODUCTION

We investigated socioeconomic disparities and the role of the main prognostic factors in receiving major surgical treatment in patients with lung cancer in England.

METHODS

Our study comprised 31 351 patients diagnosed with non-small cell lung cancer in England in 2012. Data from the national population-based cancer registry were linked to Hospital Episode Statistics and National Lung Cancer Audit data to obtain information on stage, performance status and comorbidities, and to identify patients receiving major surgical treatment. To describe the association between prognostic factors and surgery, we performed two different analyses: one using multivariable logistic regression and one estimating cause-specific hazards for death and surgery. In both analyses, we used multiple imputation to deal with missing data.

RESULTS

We showed strong evidence that the comorbidities 'congestive heart failure', 'cerebrovascular disease' and 'chronic obstructive pulmonary disease' reduced the receipt of surgery in early stage patients. We also observed gender differences and substantial age differences in the receipt of surgery. Despite accounting for sex, age at diagnosis, comorbidities, stage at diagnosis, performance status and indication of having had a PET-CT scan, the socioeconomic differences persisted in both analyses: more deprived people had lower odds and lower rates of receiving surgery in early stage lung cancer.

DISCUSSION

Comorbidities play an important role in whether patients undergo surgery, but do not completely explain the socioeconomic difference observed in early stage patients. Future work investigating access to and distance from specialist hospitals, as well as patient perceptions and patient choice in receiving surgery, could help disentangle these persistent socioeconomic inequalities.

Risks and burden of lung cancer incidence for residential petrochemical industrial complexes: A meta-analysis and application

BACKGROUND

Lung cancer is one of the most common cancers in the world. Higher incidence of lung cancer may be associated with residential proximity to a petrochemical industrial complex (PIC) due to exposure to various carcinogens, although results from previous epidemiologic studies remain inconclusive. Because disease burden due to residential inequality is a public health and societal concern, this study analyzed published data to estimate lung cancer incidence in association with residential proximity to PICs.

METHODS

We performed a meta-analysis on selected epidemiologic studies that met the following criteria: lung cancer incidence was coded by the International Classification of Diseases; exposure groups were clearly defined as residents living near PICs; and confidence intervals were available or calculable from original articles. We further applied a population attributable factor (PAF) method to estimate disease burden attributable to living near PICs in 22 European Union (EU) countries.

RESULTS

Meta-analysis included six studies with a total of 466,066 residents living near PICs in six countries. Residents living near PICs had a 19% higher risk of lung cancer compared to those who lived farther away (95% CI = 1.06-1.32). By sex, risks were higher and more significant for females (RR = 1.29; 95% CI = 1.09-1.54; P = 0.004) than males (RR = 1.12; 95% CI = 0.95-1.33; P = 0.173). By location, only groups in Europe had a significantly greater risk of lung cancer with exposure to PICs (95% CI = 1.03-1.33; P = 0.019), although groups in other locations showed similar trends. By bona fide observation, observation of residents for at least seven years provided sufficient latency to estimate risk (RR = 1.25; 95% CI = 1.17-1.34; P < 0.001). Regarding burden of lung cancer in 22 EU countries, 494 males and 478 females were attributed to living in the vicinity of a PIC annually.

CONCLUSIONS

Lung cancer incidence is significantly higher in individuals living near PICs. This result provides strong epidemiologic evidence for further policy to regulate potential pollutants near PICs.

HIGHLIGHTS

Higher incident rates of lung cancer for residents living close to petrochemical industry complex.

Geographic variation in the use of adjuvant therapy among elderly patients with resected non-small cell lung cancer

OBJECTIVES

The purpose of this study was to assess to what extent geographic variation in adjuvant treatment for non-small cell lung cancer (NSCLC) patients would remain, after controlling for patient and area-level characteristics.

MATERIALS AND METHODS

A retrospective cohort of 18,410 Medicare beneficiaries with resected, stage I-IIIA NSCLC was identified from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database. Adjuvant therapies were classified as adjuvant chemotherapy (ACT), postoperative radiation therapy (PORT), or no adjuvant therapy. Predicted treatment probabilities were estimated for each patient given their clinical, demographic, and area-level characteristics with multivariate logistic regression. Area Treatment Ratios were used to estimate the propensity of patients in a local area to receive an adjuvant treatment, controlling for characteristics of patients in the area. Areas were categorized as low-, mid- and high-use and mapped for two representative SEER registries.

RESULTS

Overall, 10%, 12%, and 78% of patients received ACT, PORT and no adjuvant therapy, respectively. Age, sex, stage, type and year of surgery, and comorbidity were associated with adjuvant treatment use. Even after adjusting for patient characteristics, substantial geographic treatment variation remained. High- and low-use areas were tightly juxtaposed within and across SEER registries, often within the same county. In some local areas, patients were up to eight times more likely to receive adjuvant therapy than expected, given their characteristics. On the other hand, almost a quarter of patients lived in local areas in which patients were more than three times less likely to receive ACT than would be predicted.

CONCLUSION

Controlling for patient and area-level covariates did not remove geographic variation in adjuvant therapies for resected NSCLC patients. A greater proportion of patients were treated less than expected, rather than more than expected. Further research is needed to better understand its causes and potential impact on outcomes.

Lung cancer survival in Norway, 1997-2011: from nihilism to optimism

We examine changes in survival and patient-, tumour- and treatment-related factors among resected and nonresected lung cancer patients, and identify subgroups with the largest and smallest survival improvements.National population-based data from the Cancer Registry of Norway, Statistics Norway and the Norwegian Patient Register were linked for lung cancer patients diagnosed during 1997-2011. The 1- and 5-year relative survival were estimated, and Cox proportional hazard regression, adjusted for selected patient characteristics, was used to assess prognostic factors for survival in lung cancer patients overall and stratified by resection status.We identified 34 157 patients with lung cancer. The proportion of histological diagnoses accompanied by molecular genetics testing increased from 0% to 26%, while those accompanied by immunohistochemistry increased from 8% to 26%. The 1-year relative survival among nonresected and resected patients increased from 21.7% to 34.2% and 75.4% to 91.5%, respectively. The improved survival remained significant after adjustment for age, sex, stage and histology. The largest improvements in survival occurred among resected and adenocarcinoma patients, while patients ≥80 years experienced the smallest increase.Lung cancer survival has increased considerably in Norway. The explanation is probably multifactorial, including improved attitude towards diagnostic work-up and treatment, and more accurate diagnostic testing that allows for improved selection for resection and improved treatment options.

Association between EPHX1 rs1051740 and lung cancer susceptibility: a meta-analysis

BACKGROUND

Microsomal epoxide hydrolase 1 (EPHX1) may play an important role in epigenetic change and DNA repair concerned with lung cancer. Several studies have investigated the association between EPHX1 rs1051740 and lung cancer risk, but there is no consensus. Therefore, we performed a meta-analysis to further identify the relationship.

METHODS

The Pubmed and Embase databases were searched for eligible studies. An odds ratio (OR) with 95% confidence intervals (CIs) was used to assess the correlation between EPHX1 rs1051740 polymorphism and lung cancer risk through a meta-analysis.

RESULTS

Overall, no significant relationship was found between EPHX1 rs1051740 and lung cancer risk (CC vs. TT: OR=1.10, 95% CI=0.88-1.36; CC+CT vs. TT: OR=1.02, 95% CI=0.88-1.18; CC vs. TT+CT: OR=1.08, 95% CI=0.91-1.27; C vs. T: OR=1.04, 95% CI=0.93-1.17; CT vs. TT: OR=0.98, 95% CI=0.85-1.13). Nevertheless, further subgroup analysis by ethnicity demonstrated that EPHX1 rs1051740 with CC genotype or C allele was an increased risk for lung cancer in Asians (CC vs. TT: OR=1.54, 95% CI=1.23-1.94; CC vs. TT+CT: OR=1.43, 95% CI=1.20-1.71; C vs. T: OR=1.26, 95% CI=1.08-1.47).

CONCLUSIONS

This meta-analysis indicates that EPHX1 rs1051740 with CC genotype or C allele may be a risk factor in Asians.

The effect of socioeconomic status on health-care delay and treatment of esophageal cancer

Background

Socioeconomic status (SES) has been focused on as a key determinant of the incidence of cancer, cancer stage at diagnosis as well as treatment choices in western countries. However, to the authors’ knowledge, little work has been done concerning the relationship of SES and esophageal cancer in China.

Methods

Patients diagnosed with primary esophageal cancer from January to December 2007 in Qilu hospital were included. Socioeconomic status was determined by a questionnaire including religion, years of schooling and high education, place of residence, occupation, annual household income, and insurance.

Results

A total of 238 cases were collected in this study. Linear-by-linear association testing revealed that health-care delay was significantly associated with SES (P = 0.009). Multivariable logistic regression analysis revealed that increased health-care delay (>2 months) was more frequently observed in patients with lower SES (OR 2.271; 95% CI 1.069–4.853). Patients diagnosed at TNM I and II were more frequently in higher SES groups (P = 0.017). The association test was statistically significant for undergoing surgical resection only (P = 0.015) and chemotherapy (P = 0.015). Multivariable logistic regression analysis revealed that surgical resection only was less performed in higher SES group compared with lower SES group (OR 0.372; 95% CI 0.188–0.734). For chemotherapy, higher SES patients had a three-fold higher likelihood compared with lower SES group (OR 3.042; 95% CI 1.335–6.928).

Conclusion

Socioeconomic status was found to be associated with health-care delay, tumor stage and treatment modalities in esophageal cancer.

Electronic supplementary material

The online version of this article (doi:10.1186/s12967-015-0579-9) contains supplementary material, which is available to authorized users.

Factors associated with timeliness of post-primary care referral, diagnosis and treatment for lung cancer: population-based, data-linkage study

Background:

The NHS Cancer Plan for England set waiting time targets for cancer referral (14 days from GP referral to first hospital appointment) and treatment (31 days from diagnosis, 62 days from urgent GP referral). Interim diagnostic intervals can also be calculated. The factors that influence timely post-primary care referral, diagnosis and treatment for lung cancer are not known.

Methods:

Northern and Yorkshire Cancer Registry, Hospital Episode Statistics and lung cancer audit data sets were linked. Logistic regression was used to investigate the factors (socioeconomic position, age, sex, histology, co-morbidity, year of diagnosis, stage and performance status (PS)) that may influence the likelihood of referral, diagnosis and treatment within target, for 28 733 lung cancer patients diagnosed in 2006–2010.

Results:

Late-stage, poor PS and small-cell histology were associated with a higher likelihood of post-primary care referral, diagnosis and treatment within target. Older patients were significantly less likely to receive treatment within the 31-day (odds ratio (OR)=0.79, 95% confidence interval (CI) 0.69–0.91) and 62-day target (OR=0.80, 95% CI 0.67–0.95) compared with younger patients.

Conclusions:

Older patients waited longer for treatment and this may be unjustified. Patients who appeared ill were referred, diagnosed and treated more quickly and this ‘sicker quicker' effect may cancel out system socioeconomic inequalities that might result in longer time intervals for more deprived patients.