Central Nervous System Disease, Education, and Race Impact Radiation Refusal in Pediatric Cancer Patients

Paediatric radiotherapy in the United Kingdom: an evolving subspecialty and a paradigm for integrated teamworking in oncology

Many different malignancies occur in children, but overall, cancer in childhood is rare. Survival rates have improved appreciably and are higher compared with most adult tumour types. Treatment schedules evolve as a result of clinical trials and are typically complex and multi-modality, with radiotherapy an integral component of many. Risk stratification in paediatric oncology is increasingly refined, resulting in a more personalized use of radiation. Every available modality of radiation delivery: simple and advanced photon techniques, proton beam therapy, molecular radiotherapy, and brachytherapy, have their place in the treatment of children's cancers. Radiotherapy is rarely the sole treatment. As local therapy, it is often given before or after surgery, so the involvement of the surgeon is critically important, particularly when brachytherapy is used. Systemic treatment is the standard of care for most paediatric tumour types, concomitant administration of chemotherapy is typical, and immunotherapy has an increasing role. Delivery of radiotherapy is not done by clinical or radiation oncologists alone; play specialists and anaesthetists are required, together with mould room staff, to ensure compliance and immobilization. The support of clinical radiologists is needed to ensure the correct interpretation of imaging for target volume delineation. Physicists and dosimetrists ensure the optimal dose distribution, minimizing exposure of organs at risk. Paediatric oncology doctors, nurses, and a range of allied health professionals are needed for the holistic wrap-around care of the child and family. Radiographers are essential at every step of the way. With increasing complexity comes a need for greater centralization of services.

A National Cancer Disparities Analysis of Predictors for Radiation Therapy Refusal by Race

PURPOSE

Radiation therapy (RT) refusal by patients with cancer is infrequent but is significant because it portends poor outcomes. No prior study has evaluated all five federally defined racial categories with respects to RT refusal. Here we use a large nationally representative population with cancer to determine: 1) which race of patients refuse RT the most and 2) predictive factors for RT refusal by race.

MATERIALS/METHODS

A retrospective study included patients ≥18 years old with diagnostically confirmed cancer between 2004-2017, using the National Cancer Database. All patients included were offered RT for first course treatment. Multivariable logistic regression assessed RT refusal (adjusted odds ratio [aOR]) with 95% confidence intervals (95%CI). Analyses were adjusted for patient factors (age, rurality, income, education, and comorbidities) and cancer characteristics (stage, cancer type, facility type, year of diagnosis, and region). Median overall survival was calculated using the Kaplan-Meier method.

RESULTS

Of 11,609,044 patients, 2,759,753 patients were included and recommended for RT by the treating physician. Median follow-up was 50 months. RT was refused by 139,383 patients (5.0%), varying by race: 416 NHPI (7.2%), 489 AIAN (5.8%), 118,186 Non-Hispanic White (5.0%), 17,427 Black (4.8%), and 2,865 Asian (4.8%) patients. The rates of annual RT refusal were increasing, especially among NHPI patients. The populations with the highest likelihood of refusing RT were NHPI (aOR=1.53, 95%CI=1.36-1.71), AIAN (aOR=1.24, 95%CI=1.12-1.37), and Black (aOR=1.11, 95%CI=1.09-1.14) patients, compared to Non-Hispanic White patients. Older age and higher comorbidity burden predicted RT refusal across all races. Median overall survival was 81 months and 144 months for patients who refused RT and received RT, respectively.

CONCLUSIONS

Indigenous and Black patients are more likely to refuse RT, which may contribute to inferior cancer outcomes. Understanding NHPI and AIAN patient perspectives and perceptions may elucidate interventions to mitigate these disparities.

Disparities in Access to Radiation Therapy by Race and Ethnicity in the United States With Focus on American Indian/Alaska Native People

OBJECTIVES

Striking disparities in access to radiation therapy (RT) exist, especially among racial and ethnic-minority patients. We analyzed census block group data to evaluate differences in travel distance to RT as a function of race and ethnicity, socioeconomic status, and rurality.

METHODS

The Directory of Radiotherapy Centers provided the addresses of facilities containing linear accelerators for RT. We classified block groups as majority (≥ 50%) American Indian/Alaska Native (AI/AN), black, white, Asian, no single racial majority, or Hispanic regardless of race. We used the Area Deprivation Index to classify deprivation and Rural-Urban Commuting Area codes to classify rurality. Generalized linear mixed models tested associations between these factors and distance to nearest RT facility.

RESULTS

Median distance to nearest RT facility was 72 miles in AI/AN-majority block groups, but 4 to 7 miles in block groups with non-AI/AN majorities. Multivariable models estimated that travel distances in AI/AN-majority block groups were 39 to 41 miles longer than in areas with non-AI/AN majorities. Travel distance was 1.3 miles longer in the more deprived areas versus less deprived areas and 16 to 32 miles longer in micropolitan, small town, and rural areas versus metropolitan areas.

CONCLUSIONS

Cancer patients in block groups with AI/AN-majority populations, nonmetropolitan location, and low socioeconomic status experience substantial travel disparities in access to RT. Future research with more granular community- and individual-level data should explore the many other known barriers to access to cancer care and their relationship to the barriers posed by distance to RT care.

Health Disparities in Cancer Among American Indians and Alaska Natives

American Indians and Alaska Natives (AI/AN) are underserved populations who suffer from several health disparities, 1 of which is cancer. Malignancies, especially cancers of the breast, liver, and lung, are common causes of death in this population. Health care disparities in this population include more limited access to diagnostic radiology because of geographic and/or health system limitations. Early detection of these cancers may be enabled by improving patient and physician access to medical imaging. Awareness by the radiology community of the cancer disparities among this population is needed to support research targeted to this specific ethnic group and to support outreach efforts to provide more imaging opportunities. Providing greater access to imaging facilities will also improve patient compliance with screening recommendations, ultimately improving mortality in these populations.

Disparities in Access to Radiation Therapy Facilities Among American Indians/Alaska Natives and Hispanics in Washington State

PURPOSE

Racial and ethnic minorities in the state of Washington experience higher cancer mortality relative to whites. We sought to characterize differences in travel distance to radiation therapy (RT) facilities in Washington by race and ethnicity with a special focus on non-Hispanic American Indians and Alaska Natives as a contributor to limited access and cancer disparities.

METHODS AND MATERIALS

Geocoded mortality data from Washington Department of Health (2011-2018) were used to identify decedents with mortality related to all-causes, all cancers, and cancers likely requiring access to RT. This was determined from optimal RT usage estimates by diagnosis. RT facility locations were ascertained from the Directory of Radiation Therapy Centers and confirmed. Distance from decedents' address listed on death certificates to nearest RT facility was calculated. Generalized mixed models were used for statistical analysis.

RESULTS

We identified 418,754 deaths; 109,134 were cancer-related, 60,973 likely required RT. Among decedents with cancers likely requiring RT, non-Hispanic American Indians and Alaska Natives decedents would have had to travel 1.16 times (95% confidence interval [CI], 1.09-1.24) farther from their residences to reach the nearest treatment facility compared with non-Hispanic whites. This association existed in metro counties but was more pronounced in nonmetro counties (1.39 times farther; 95% CI, 1.22-1.58). In addition, Hispanics would have had to travel 1.11 times farther (95% CI, 1.06-1.16) to reach the nearest facility compared with non-Hispanic whites, primarily due to differences in urban counties. Decedents in nonmetro counties lived on average 35 miles (SD = 29) from RT centers and non-Hispanic American Indians and Alaska Natives in nonmetro counties 53 miles (SD = 38). Compared with non-Hispanic white decedents, those who were non-Hispanic black, non-Hispanic Asian, and non-Hispanic Native Hawaiian decedents lived closer to RT facilities.

CONCLUSIONS

We observed significant disparities in access to RT facilities in Washington, specifically for non-Hispanic American Indians and Alaska Natives and rural decedents. The findings call for initiatives to improve access to critical cancer treatment services for these underserved populations with known disparities in cancer deaths.