Socioeconomic position and surgery for early-stage non-small-cell lung cancer: A population-based study in Denmark

Nurse navigation, symptom monitoring and exercise in vulnerable patients with lung cancer: feasibility of the NAVIGATE intervention

We developed the Navigate intervention to improve survival among vulnerable lung cancer patients. In this intervention-only study, we examined feasibility in terms of recruitment, retention, attendance, adherence, and acceptability to specify adjustments to study procedures and intervention components prior to a randomized trial. The Navigate intervention includes nurse navigation, patient-reported outcomes, and physical exercise. Patients ≥ 18 years old, diagnosed with non-small cell lung cancer at any stage, with performance status ≤ 2, eligible for cancer treatment and vulnerable according to a screening instrument were included. The recruitment goal of eligible patients was 40% while the retention goal was 85%. The predefined cut-offs for sufficient attendance and adherence were ≥ 75%. Acceptability was evaluated by semi-structured interviews with participants, nurse navigators, and physiotherapists. Seventeen (56%) out of 30 screened patients were considered vulnerable and eligible for the study, 14 (82%) accepted participation, and 3 (21%) were subsequently excluded due to ineligibility, leaving 11 patients. Four patients dropped out (36%) and four patients died (36%) during follow-up and 3 (27%) were retained. All 11 patients participated in nurse sessions (mean 16, range 1-36) with 88% attendance and dialogue tools being applied in 68% of sessions. Ninety-one percent of patients responded to PROs (mean of 9 PROs, range 1-24) with 76% of the PRO questionnaires used (attendance) and 100% adherence (completion of all questions in PRO questionnaires), and 55% participated in exercise sessions with 58% attendance and 85% adherence. We identified important barriers primarily related to transportation, but overall acceptability was high. The Navigate intervention was feasible with high participation, acceptability and satisfactory adherence. Retention and exercise attendance were low, which resulted in adjustments.Trial registration: The feasibility study was initiated prior to the multicenter randomized controlled trial registered by ClinicalTrials.gov (number: NCT05053997; date 23/09/2021).

What health inequalities exist in access to, outcomes from and experience of treatment for lung cancer? A scoping review

OBJECTIVES

Lung cancer (LC) continues to be the leading cause of cancer-related deaths and while there have been significant improvements in overall survival, this gain is not equally distributed. To address health inequalities (HIs), it is vital to identify whether and where they exist. This paper reviews existing literature on what HIs impact LC care and where these manifest on the care pathway.

DESIGN

A systematic scoping review based on Arksey and O'Malley's five-stage framework.

DATA SOURCES

Multiple databases (EMBASE, HMIC, Medline, PsycINFO, PubMed) were used to retrieve articles.

ELIGIBILITY CRITERIA

Search limits were set to retrieve articles published between January 2012 and April 2022. Papers examining LC along with domains of HI were included. Two authors screened papers and independently assessed full texts.

DATA EXTRACTION AND SYNTHESIS

HIs were categorised according to: (a) HI domains: Protected Characteristics (PC); Socioeconomic and Deprivation Factors (SDF); Geographical Region (GR); Vulnerable or Socially Excluded Groups (VSG); and (b) where on the LC pathway (access to, outcomes from, experience of care) inequalities manifest. Data were extracted by two authors and collated in a spreadsheet for structured analysis and interpretation.

RESULTS

41 papers were included. The most studied domain was PC (32/41), followed by SDF (19/41), GR (18/41) and VSG (13/41). Most studies investigated differences in access (31/41) or outcomes (27/41), with few (4/41) exploring experience inequalities. Evidence showed race, rural residence and being part of a VSG impacted the access to LC diagnosis, treatment and supportive care. Additionally, rural residence, older age or male sex negatively impacted survival and mortality. The relationship between outcomes and other factors (eg, race, deprivation) showed mixed results.

CONCLUSIONS

Findings offer an opportunity to reflect on the understanding of HIs in LC care and provide a platform to consider targeted efforts to improve equity of access, outcomes and experience for patients.

Who are the vulnerable lung cancer patients at risk for not receiving first-line curative or palliative treatment?

BACKGROUND

To identify non-small-cell lung cancer (NSCLC) patients in need of comprehensive support, we examined the association between patient and disease-related factors of vulnerability related to not receiving guideline-recommended treatment.

MATERIAL AND METHODS

We identified 14,597 non-small-cell lung cancer (NSCLC) patients with performance status <3 during 2013-2018 in the Danish Lung Cancer Registry. Multivariate logistic regression models were used to estimate Odds Ratios (ORs) and 95% confidence intervals (CIs) for receiving guideline-recommended treatment according to stage, comorbidities, age, performance status, long distance to hospital, cohabitation status, education and alcohol abuse.

RESULTS

21% of stage I-IIIA NSCLC patients did not receive curative treatment while 10% with stage IIIB-IV did not receive any oncological therapy. Factors associated with reduced likelihood of receiving curative treatment included: advanced stage (OR = 0.45; 95% CI = 0.42-0.49), somatic comorbidity (OR = 0.72; 95% CI = 0.63-0.83), age ≥ 80 years (OR = 0.59; 95% CI = 0.55-0.64), performance status = 2 (OR = 0.33; 95% CI = 0.28-0.39) and living alone (OR = 0.79; 95% CI = 0.69-0.90). Results were similar for stage IIIB-IV NSCLC patients, although a statistically significant association was also seen for long distances to the hospital (OR = 0.71; 95% CI = 0.58-0.86).

CONCLUSIONS

Several factors are associated with not receiving guideline-recommended NSCLC treatment with age, performance status, comorbidity and stage being most predictive of no treatment receipt. Efforts should be made to develop support for vulnerable lung cancer patients to improve adherence to optimal first-line therapy.

NAVIGATE: improving survival in vulnerable patients with lung cancer through nurse navigation, symptom monitoring and exercise - study protocol for a multicentre randomised controlled trial

INTRODUCTION AND AIM

Low socioeconomic position (SEP) has been shown to be strongly associated with impaired lung cancer survival. Barriers related to receiving recommended treatment among patients with lung cancer with low SEP may include adverse health behaviour and limited physical and psychosocial resources influencing the ability to react on high-risk symptoms and to navigate the healthcare system. To address the underlying factors that drive both decisions of treatment, adherence to treatment and follow-up in vulnerable patients with lung cancer, we developed the Navigate intervention. The aim of this randomised controlled trial is to investigate the effect of the intervention on survival (primary outcome), lung cancer treatment adherence, health-related quality of life and other psychosocial outcomes as well as health costs and process evaluation (secondary outcomes) in a study population of vulnerable patients with lung cancer.

METHODS AND ANALYSIS

This two-armed multicentre randomised trial will recruit patients from five lung cancer clinics in Denmark identified as vulnerable according to a screening instrument with nine clinical and patient-reported vulnerability criteria developed for the study. We will enrol 518 vulnerable patients >18 years old diagnosed with non-small cell lung cancer at all stages with a performance status <2. Participants will be randomly allocated to either standard treatment and intervention or standard treatment alone. The Navigate intervention is based on principles from motivational interviewing and includes three components of nurse navigation, systematic monitoring of patient-reported outcomes (PROs) and physical exercise in a person-centred delivery model. Data will be collected at baseline and 3, 6, 12 months after randomisation using questionnaires, clinical data and physical function tests.

ETHICS AND DISSEMINATION

Ethics Committee, Region Zealand (SJ-884/EMN-2020-37380) and the Data Protection Agency in Region Zealand (REG-080-2021) approved the trial. Participants will provide written informed consent. Results will be reported in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT05053997.

Cancer rehabilitation and palliative care for socially vulnerable patients in Denmark: an exploration of practices and conceptualisations

Background:

Despite a tax-funded, needs-based organisation of the Danish health system, social inequality in cancer rehabilitation and palliative care (PC) has been noted repeatedly. Little is known about how best to improve access and participation in cancer rehabilitation and PC for socio-economically disadvantaged and socially vulnerable patients.

Aim:

To gather, synthesise and describe practice-orientated development studies presented in Danish-language publications and examine the underpinning conceptualisations of social inequality and vulnerability; explore related views of stakeholders working in the field.

Methods:

The study comprised a narrative review of Danish-language literature on practice-orientated development studies which address social inequality and vulnerability in cancer rehabilitation and PC and an online stakeholder consultation workshop with Danish professionals and academics working in the field.

Results:

Two themes characterise the included publications (n = 8): types of interventions; conceptualisations of social inequality and vulnerability; three themes were identified in the workshop data: focus and type of interventions; organisation of cancer care; and vulnerability of the healthcare system. The publications and the workshop participants (n = 12) favoured approaches which provide additional individualised resources throughout the cancer trajectory for this patient group. The terms social inequality and social vulnerability are largely used interchangeably, and associated with low income and no or little education yet qualified with multiple descriptors, which reflect the diverse socio-economic situations professionals encounter in cancer patients and their psychosocial needs.

Conclusion:

Addressing social inequality and vulnerability in cancer rehabilitation and PC in Denmark entails practical and conceptual challenges. Of importance is individualised support and the integration of rehabilitation and PC into standardised care pathways. To conceive of social vulnerability as a layered, dynamic, relational and contextual concept reflects current practice in identifying the diversity of cancer patients who may benefit from additional support in accessing and participating in rehabilitation and PC.

Narrative review of socioeconomic and racial disparities in the treatment of early stage lung cancer

Background

To review and discuss the current literature regarding socio-economic and racial disparities in the treatment of early-stage non-small cell lung cancer (NSCLC).

Methods

Narrative review of peer reviewed literature synthesizing findings retrieved from searches of computerized databases, primary article reference lists, authoritative texts and expert options.

Results

The current incidence of lung cancer appears to be similar between White and Black patients. However, Black patients are substantially less likely to receive curative intent surgery. Mitigation strategies do exist to narrow this inequity. Lower socioeconomic status (SES) is associated with a higher incidence of lung cancer, lower utilization of surgery and poorer outcomes after surgery.

Conclusions

Race and SES remain closely linked to outcomes in lung cancer. Outcomes are still worse when controlling for stage and specifically, in early-stage disease, surgical therapy is consistently underused in Black patients and patients of low SES.

Socioeconomic Status And Acute Stroke Care: Has The Inequality Gap Been Closed?

Purpose

Socioeconomic inequality in stroke care occurs even in countries with free access to health care. We aimed to investigate the association between socioeconomic status and guideline-recommended acute care in Denmark during the last decade.

Design

We conducted a nationwide, population-based study. We used household income, employment status, and education as markers of socioeconomic status and adjusted the results for relevant clinical covariates. We used weighted linear regression models to analyse empirical log odds of performance measure fulfillment at patient level.

Setting

Public hospitals in Denmark.

Participants

A total of 110,848 consecutive stroke patients discharged between 2004 and 2014.

Intervention(s)

Acute stroke care according to clinical guidelines.

Main outcome measure(s)

Guideline-recommended care was defined in two ways based on clinical performance measures: the percentage of fulfilled measures used throughout the study period (m=8) (model 1) and the percentage of fulfilled measures used at the time of discharge (m=8 to 16) (model 2).

Results

Compared with high family income, low income was negatively associated with the guideline-recommended care; odds ratios (95% CI) were 0.89 (0.85–0.93) in model 1 and 0.81 (0.77–0.85) in model 2. Low family income was negatively associated with fulfillment of 14 of the 16 performance measures. In general, the percentage of performance measures fulfilled increased over time from 70% (95% CI 63–76) to 85% (95% CI 83–87).

Conclusion

Socioeconomic inequality in guideline-recommended stroke care remains despite overall improvements in a setting with free access to care and systematic monitoring of health care quality.

Socioeconomic inequality in cancer survival - changes over time. A population-based study, Denmark, 1987-2013

Background: Socioeconomic inequality in survival after cancer have been reported in several countries and also in Denmark. Changes in cancer diagnostics and treatment may have changed the gap in survival between affluent and deprived patients and we investigated if the differences in relative survival by income has changed in Danish cancer patients over the past 25 years. Methods: The 1- and 5-year relative survival by income quintile is computed by comparing survival among cancer patients diagnosed 1987-2009 to the survival of a cancer-free matched sample of the background population. The comparison is done within the 15 most common cancers and all cancers combined. The gap in relative survival due to socioeconomic inequality for the period 1987-1991 is compared the period 2005-2009. Results: The relative 5-year survival increased for all 15 cancer sites investigated in the study period. In general, low-income patients diagnosed in 1987-1991 had between 0% and 11% units lower 5-year relative survival compared with high-income patients; however, only four sites (breast, prostate, bladder and head & neck) were statistically different. In patients diagnosed 2005-2009, the gap in 5-year RS was ranging from 2% to 22% units and statistically significantly different for 9 out of 15 sites. The results for 1-year relative survival were similar to the 5-year survival gap. An estimated 22% of all deaths at five years after diagnosis could be avoided had patients in all income groups had same survival as the high-income group. Conclusion: In this nationwide population-based study, we observed that the large improvements in both short- and long-term cancer survival among patients diagnosed 1987-2009. The improvements have been most pronounced for high-income cancer patients, leading to stable or even increasing survival differences between richest and poorest patients. Improving survival among low-income patients would improve survival rates among Danish cancer patients overall and reduce differences in survival when compared to other Western European countries.

Achieving Thoracic Oncology data collection in Europe: a precursor study in 35 Countries

BACKGROUND

A minority of European countries have participated in international comparisons with high level data on lung cancer. However, the nature and extent of data collection across the continent is simply unknown, and without accurate data collection it is not possible to compare practice and set benchmarks to which lung cancer services can aspire.

METHODS

Using an established network of lung cancer specialists in 37 European countries, a survey was distributed in December 2014. The results relate to current practice in each country at the time, early 2015. The results were compiled and then verified with co-authors over the following months.

RESULTS

Thirty-five completed surveys were received which describe a range of current practice for lung cancer data collection. Thirty countries have data collection at the national level, but this is not so in Albania, Bosnia-Herzegovina, Italy, Spain and Switzerland. Data collection varied from paper records with no survival analysis, to well-established electronic databases with links to census data and survival analyses.

CONCLUSION

Using a network of committed clinicians, we have gathered validated comparative data reporting an observed difference in data collection mechanisms across Europe. We have identified the need to develop a well-designed dataset, whilst acknowledging what is feasible within each country, and aspiring to collect high quality data for clinical research.

Socio-economic inequalities in stage at diagnosis, and in time intervals on the lung cancer pathway from first symptom to treatment: systematic review and meta-analysis

Cancer diagnosis at an early stage increases the chance of curative treatment and of survival. It has been suggested that delays on the pathway from first symptom to diagnosis and treatment may be socio-economically patterned, and contribute to socio-economic differences in receipt of treatment and in cancer survival. This review aimed to assess the published evidence for socio-economic inequalities in stage at diagnosis of lung cancer, and in the length of time spent on the lung cancer pathway. MEDLINE, EMBASE and CINAHL databases were searched to locate cohort studies of adults with a primary diagnosis of lung cancer, where the outcome was stage at diagnosis or the length of time spent within an interval on the care pathway, or a suitable proxy measure, analysed according to a measure of socio-economic position. Meta-analysis was undertaken when there were studies available with suitable data. Of the 461 records screened, 39 papers were included in the review (20 from the UK) and seven in a final meta-analysis for stage at diagnosis. There was no evidence of socio-economic inequalities in late stage at diagnosis in the most, compared with the least, deprived group (OR=1.04, 95% CI=0.92 to 1.19). No socio-economic inequalities in the patient interval or in time from diagnosis to treatment were found. Socio-economic inequalities in stage at diagnosis are thought to be an important explanatory factor for survival inequalities in cancer. However, socio-economic inequalities in stage at diagnosis were not found in a meta-analysis for lung cancer.

PROSPERO PROTOCOL REGISTRATION NUMBER

CRD42014007145.

The Danish Lung Cancer Registry

Aim of database

The Danish Lung Cancer Registry (DLCR) was established by the Danish Lung Cancer Group. The primary and first goal of the DLCR was to improve survival and the overall clinical management of Danish lung cancer patients.

Study population

All Danish primary lung cancer patients since 2000 are included into the registry and the database today contains information on more than 50,000 cases of lung cancer.

Main variables

The database contains information on patient characteristics such as age, sex, diagnostic procedures, histology, tumor stage, lung function, performance, comorbidities, type of surgery, and/or oncological treatment and complications. Since November 2013, DLCR data on Patient -Reported Outcome Measures is also included.

Descriptive data

Results are primarily reported as quality indicators, which are published online monthly, and in an annual report where the results are commented for local, regional, and national audits. Indicator results are supported by descriptive reports with details on diagnostics and treatment.

Conclusion

DLCR has since its creation been used to improve the quality of treatment of lung cancer in Denmark and it is increasingly used as a source for research regarding lung cancer in Denmark and in comparisons with other countries.

Is England closing the international gap in cancer survival?

BACKGROUND

We provide an up-to-date international comparison of cancer survival, assessing whether England is 'closing the gap' compared with other high-income countries.

METHODS

Net survival was estimated using national, population-based, cancer registrations for 1.9 million patients diagnosed with a cancer of the stomach, colon, rectum, lung, breast (women) or ovary in England during 1995-2012. Trends during 1995-2009 were compared with estimates for Australia, Canada, Denmark, Norway and Sweden. Clinicians were interviewed to help interpret trends.

RESULTS

Survival from all cancers remained lower in England than in Australia, Canada, Norway and Sweden by 2005-2009. For some cancers, survival improved more in England than in other countries between 1995-1999 and 2005-2009; for example, 1-year survival from stomach, rectal, lung, breast and ovarian cancers improved more than in Australia and Canada. There has been acceleration in lung cancer survival improvement in England recently, with average annual improvement in 1-year survival rising to 2% during 2010-2012. Survival improved more in Denmark than in England for rectal and lung cancers between 1995-1999 and 2005-2009.

CONCLUSIONS

Survival has increased in England since the mid-1990s in the context of strategic reform in cancer control, however, survival remains lower than in comparable developed countries and continued investment is needed to close the international survival gap.

Dosimetric evaluation of compensator intensity modulation-based stereotactic body radiotherapy for Stage I non-small-cell lung cancer

OBJECTIVE

To evaluate the dosimetry of compensator intensity modulation-based stereotactic body radiotherapy (SBRT) [non-coplanar intensity-modulated radiotherapy (ncIMRT)], its use was compared with that of three-dimensional conformation-based SBRT, for patients with Stage I non-small-cell lung cancer (NSCLC).

METHODS

21 consecutive patients with Stage I NSCLC were treated with ncIMRT or SBRT at Tokyo Medical University. To compare the two techniques, ncIMRT and SBRT plans for each patient were generated, where the planning target volume (PTV) coverages were adjusted to be equivalent to each other. The prescribed dose was set as 75 Gy in 30 fractions. PTV coverage, conformity index, conformation number (CN) and homogeneity index (HI) were used to compare the two strategies.

RESULTS

There was no statistically significant difference between PTV coverage for the 100%, 95% and 90% dose levels in the SBRT plan and those in the ncIMRT plan. The CN values were 0.53 ± 0.13 in the SBRT plan and 0.72 ± 0.10 in the ncIMRT plan. These values were significantly better than those of the SBRT plan (p < 0.001). The HI in the ncIMRT plan was 1.04 ± 0.03%, which was also significantly better than that of SBRT.

CONCLUSION

The ncIMRT plan provided superior conformity and reduced the doses to the lung for patients with Stage I NSCLC.

ADVANCES IN KNOWLEDGE

The delivery technique with compensator intensity modulation-based SBRT was evaluated. Concerning target motion, this is thought to be more robust and safer than SBRT for early-stage NSCLC.

Social position and referral to rehabilitation among cancer patients

OBJECTIVES

In Denmark, most healthcare services, including cancer treatment and rehabilitation, are offered free of charge by referral from a treating physician; thus, social equality should be expected. In a population-based cohort study of registry-based data, we examined the association between socioeconomic position, measured as educational level, and referral to rehabilitation services among cancer patients.

MATERIAL AND METHODS

Through the Danish Cancer Registry, we identified all people resident in the Municipality of Copenhagen with cancer diagnosed in 2007-2012. Information on all rehabilitation referrals was retrieved from the Municipal Centre for Cancer Rehabilitation for 2009-2012. Information on demographic and socioeconomic characteristics was obtained from national Danish registers. The Cox proportional hazards model was used to investigate associations between educational level and referral to rehabilitation with adjustment for sex, age, diagnosis, disposable income, cohabitation status and number of children living at home at the time of diagnosis.

RESULTS

A primary cancer was diagnosed in 13 840 people, of whom 2148 (16%) were referred to rehabilitation services during follow-up. In the fully adjusted model, we found education to be a predictor of referral, with a hazard ratio of 1.33 (95% CI 1.19-1.49) for patients with long education and a hazard ratio of 1.15 (95% CI 1.03-1.29) for patients with medium education as compared with patients with short education.

CONCLUSIONS

Our findings suggest that, even after differences in demographics and cancer characteristics are accounted for, referral to rehabilitation services is not equally distributed by social group. Higher educational level is associated with a higher probability of referral to rehabilitation services.

Socioeconomic position and survival after lung cancer: Influence of stage, treatment and comorbidity among Danish patients with lung cancer diagnosed in 2004-2010

BACKGROUND

To address social inequality in survival after lung cancer, it is important to consider how socioeconomic position (SEP) influences prognosis. We investigated whether SEP influenced receipt of first-line treatment and whether socioeconomic differences in survival could be explained by differences in stage, treatment and comorbidity.

MATERIAL AND METHODS

In the Danish Lung Cancer Register, we identified 13 045 patients with lung cancer diagnosed in 2004-2010, with information on stage, histology, performance status and first-line treatment. We obtained age, gender, vital status, comorbid conditions and socioeconomic information (education, income and cohabitation status) from nationwide population-based registers. Associations between SEP and receipt of first-line treatment were analysed in multivariate logistic regression models and those with overall mortality in Cox regression models with stepwise inclusion of possible mediators.

RESULTS

For both low- and high-stage lung cancer, adjusted ORs for first-line treatment were reduced in patients with short education and low income, although the OR for education did not reach statistical significance in men with high-stage disease. Patients with high-stage disease who lived alone were less likely to receive first-line treatment. The socioeconomic difference in overall survival was partly explained by differences in stage, treatment and comorbidity, although some differences remained after adjustment. Among patients with high-stage disease, the hazard ratio (HR) for death of those with low income was 1.12 (95% CI 1.05-1.19) in comparison with those with high income. Among patients with low-stage disease, those who lived alone had a 14% higher risk for dying (95% CI 1.05-1.25) than those who lived with a partner. The differences in risk for death by SEP were greatest in the first six months after diagnosis.

CONCLUSION

Socioeconomic differences in survival after lung cancer are partly explained by social inequality in stage, first-line treatment and comorbidity. Efforts should be made to improve early diagnosis and adherence to first-line treatment recommendations among disadvantaged lung cancer patients.

Patients with localized non-small cell lung cancer miss out on curative surgery with distance from specialist care

BACKGROUND

To determine whether increasing distance to the nearest accessible specialist hospital (NASH, a public hospital with a thoracic surgical service) increases a patient's likelihood of missing out on curative surgery for localized non-small cell lung cancer (NSCLC).

METHOD

Population-based study of cancer registry records for 27 033 people with lung cancer diagnosed in New South Wales, Australia, between 2000 and 2008 linked to hospital admission records. This analysis includes 3240 patients with localized NSCLC admitted to hospital within 12 months of diagnosis.

RESULTS

Patients who lived 100+ km from the NASH were more likely to have no surgery (50.6%) than those living 0-39 km away (37.6%) and more likely to attend general hospitals for their care (52.2% at 100+ km, 14.8% at 0-39 km). Relative to patients living 0-39 km from the NASH and attending a specialist hospital for their care, the odds ratio (OR) of not having surgery was high if patients attended a general hospital (adjusted OR 5.99, 95% confidence interval (CI) 3.87-9.26, for those 0-39 km distant) and even higher as distance from the NASH increased (24.68, 95% CI 12.37-49.13 for 40-49 km and 30.10, 95% CI 18.2-49.40 for 100+ km). For patients treated in specialist hospitals (public or private), the trend with distance was opposite: relative to 0-39 km, the OR was 0.29 (95% CI 0.15-0.50) at 40-99 km and 0.14 (95% CI 0.08-0.26) at 100+ km.

CONCLUSIONS

Patients with localized NSCLC are most likely to have no potentially curative surgery if they live distant from a specialist hospital and attend a general hospital for their care.

Research in cancer care disparities in countries with universal healthcare: mapping the field and its conceptual contours

The paper reviews published studies focused on disparities in receipt of cancer treatments and supportive care services in countries where cancer care is free at the point of access. We map these studies in terms of the equity stratifiers they examined, the countries in which they took place, and the care settings and cancer populations they investigated. Based on this map, we reflect on patterns of scholarly attention to equity and disparity in cancer care. We then consider conceptual challenges and opportunities in the field, including how treatment disparities are defined, how equity stratifiers are defined and conceptualized and how disparities are explained, with special attention to the challenge of psychosocial explanations.