Estimating the Need for Palliative Radiotherapy for Brain Metastasis: A Benchmarking Approach

Variations in whole brain radiation therapy fractionation for brain metastases in Victoria

INTRODUCTION

We aim to evaluate the use of different whole brain radiation therapy (WBRT) fractionation schedules for brain metastases (BM) in Victoria, and the factors associated with it.

METHODS

This is a population-based cohort of patients who received radiation therapy for BM between 2012 and 2017, as captured in the Victorian Radiotherapy Minimum Dataset. We excluded patients with primary brain tumour and those who had 'prophylactic' intent treatment. The Cochran-Armitage test was used to evaluate changing trend in WBRT fractionation. Multivariate multinomial logistic regressions were used to evaluate factors associated with WBRT fractionation.

RESULTS

Of the 3111 patients who had WBRT, 1048 (45%), 1291 (42%) and 312 (13%) had ≤5, 6-10 and >10 fractions WBRT respectively. There was progressive increase in ≤5 fractions WBRT use over time, from 37% in 2012 to 50% in 2017 (P-trend < 0.001). In multivariate analyses, increasing age, patients with gastrointestinal cancer, patients living in remote/regional areas and more recent treatment were associated with the use of shorter WBRT fractionation (≤5 fractions), while patients who had WBRT plus stereotactic radiosurgery, and those treated in private institutions were associated with the use of prolonged WBRT fractionation (≥6 fractions). Three hundred eighty-nine (13%) patients died within 30 days of WBRT, of which 241 (64%), 119 (32%) and 17 (5%) had ≤5, 6-10 and > 10 fractions WBRT respectively.

CONCLUSION

We observed large variations in WBRT fractionation that are associated with patient, tumour, treatment and institutional factors. It is important to continuously monitor and benchmark our practice in order to reduce potentially unwarranted variations.

Geographical distance and reduced access to palliative radiotherapy: systematic review and meta-analysis

BACKGROUND

Palliative radiotherapy (PRT) is an effective way of reducing symptoms caused by advanced incurable cancer. Several studies have investigated factors that contribute to inequalities in access to PRT; distance to a radiotherapy centre has been identified as one potential barrier.

AIM

To assess whether there is an association between distance to a radiotherapy centre and utilisation rates of PRT in adults with cancer.

METHODS

A systematic review and meta-analysis protocol was registered in the PROSPERO database (CRD42020190772). MEDLINE, EMBASE, CINAHL and APA-PsycINFO were searched for relevant papers up to 28 February 2021.

RESULTS

Twenty-one studies were included. Twelve studies focused on whether patients with incurable cancer received PRT, as part of their treatment package. Pooled results reported that living ≥50 km vs <50 km from the radiotherapy centre was associated with a reduced likelihood of receiving PRT (OR 0.84 (95%CI 0.80, 0.88)). Nine focused on distance from the radiotherapy centre and compared single-fraction (SF) versus multiple-fraction PRT, indicating that patients living further away were more likely to receive SF. Pooled results comparing ≥50 km versus <50 km showed increased odds of receiving SF for those living ≥50 km (OR 1.48 (95%CI 1.26,1.75)).

CONCLUSION

Patients living further away from radiotherapy centres were less likely to receive PRT and those who received PRT were more likely to receive SF PRT, providing some evidence of inequalities in access to PRT treatment based on proximity to centres providing radiotherapy. Further research is needed to understand whether these inequalities are influenced by clinical referral patterns or by patients unwilling or unable to travel longer distances.

PROSPERO REGISTRATION NUMBER

CRD42020190772.

Patterns of palliative radiotherapy fractionation for brain metastases patients in New South Wales, Australia

BACKGROUND AND PURPOSE

There is a paucity of studies examining variation in the use of palliative radiation therapy (RT) fractionation for brain metastases. The aim of this study is to assess variation in palliative RT fractionation given for brain metastases in New South Wales (NSW), Australia, and identify factors associated with variation.

MATERIALS AND METHODS

This is a population-based cohort of patients who received whole brain RT (WBRT) for brain metastases (2009-2014), as captured in the NSW Central Cancer Registry. A logistic regression model was used to identify factors associated with fractionation type.

RESULTS

Of the 2,698 patients that received WBRT, 1,389 courses (51%) were < 6 fractions, 1,050 courses (39%) were 6-10 fractions, and 259 courses (10%) were > 10 fractions. Older patients were more likely to be treated with shorter courses (P < 0.0001). Patients with primary lung cancers were more likely to receive shorter courses compared with other primary cancers (P < 0.0001). Patients without surgical excision were more likely to receive < 6 fractions compared to those who underwent surgical excision. Shorter courses were more likely to be delivered to patients with the most disadvantaged socioeconomic status (SES) compared with patients with the least disadvantaged SES (P < 0.0001). There were significant fluctuations in the proportion of courses using lower number of fractions over time from 2009 to 2014, but no apparent trend (P = 0.02). There was wide variation in the proportion of shorter courses across residence local health districts, ranging from 24% to 69% for < 6 fractions, 21% to 72% for 6-10 fractions, and 4% to 20% for > 10 fractions (P < 0.0001).

CONCLUSION

This study has identified significant unwarranted variations in fractionation for WBRT in NSW. Accelerating the uptake of shorter fractionation regimens, if warranted through evidence, should be prioritised to enhance evidence-based care.

Estimating the optimal perioperative chemotherapy utilization rate for muscle-invasive bladder cancer

Background

Identifying optimal chemotherapy (CT) utilization rates can drive improvements in quality of care. We report a benchmarking approach to estimate the optimal rate of perioperative CT for muscle‐invasive bladder cancer (MIBC).

Methods

The Ontario Cancer Registry and linked treated records were used to identify neoadjuvant and adjuvant CT rates among patients with MIBC during 2004‐2013. Monte Carlo simulation was used to estimate the proportion of observed rate variation that could be due to chance alone. The criterion‐based benchmarking approach was used to explore whether social and health‐system factors were associated with CT rates. We also used the “pared‐mean” approach to identify a benchmark population of hospitals with the highest treatment rates. Hospital CT rates were adjusted for case mix and simulated using a multi‐level multivariable model and a parametric bootstrapping approach.

Results

The study population included 2581 patients; perioperative CT was delivered to 31% (798/2581). Multivariate analysis showed that treatment was strongly associated with patient socioeconomic status and hospital teaching status. The benchmark rate was 36%. Unadjusted CT rates were significantly different across hospitals (range 0%‐52%, P < .001). The unadjusted benchmark perioperative CT rate was 45% (95% CI 40%‐50%); utilization rate in nonbenchmark hospitals was 28% (95% CI 26%‐30%). When using simulated CT rates adjusted for case mix, the benchmark CT rate was 41% (95% CI 35%‐47%) and the nonbenchmark hospital CT rate was 30% (95% CI 28%‐32%). The simulation analysis suggested that the observed component of variation (38%) was outside the 95% CI (22%‐28%) of what could be expected due to chance alone.

Conclusions

There is significant systematic variation in perioperative CT rates for MIBC across hospitals in routine practice. The benchmark perioperative CT rate for MIBC is 36%‐41%.

Estimating the optimal rate of adjuvant chemotherapy utilization for stage III colon cancer

Background

Identifying optimal chemotherapy utilization rates can drive improvements in quality of care. We report a benchmarking approach to estimate the optimal rate of adjuvant chemotherapy (ACT) for stage III colon cancer.

Methods

The Ontario Cancer Registry and linked treated records were used to identify ACT utilization. Monte Carlo simulation was used to estimate the proportion of ACT rate variation that could be due to chance alone. The criterion‐based benchmarking approach was used to explore whether socioeconomic or system‐level factors were associated with ACT. We also used the “pared‐mean” approach to identify a benchmark population of hospitals with the highest ACT rates.

Results

The study population included 2801 patients; ACT was delivered to 66% (1861/2801). Monte Carlo simulation suggested that the observed component of variation (15.6%) in ACT rates was within the 95% CI (11.5%‐17.3%) of what could be expected due to chance alone; the nonrandom component of ACT rate variation across hospitals was only 1.5%. There was no difference in hospital ACT rate by teaching status (P = .107), cancer center status (P = .362), or having medical oncology on site (P = .840). Unadjusted ACT rates varied across hospitals (range 44%‐91%, P = .017). The unadjusted benchmark ACT rate was 81% (95%CI 76%‐86%); utilization rate in non‐benchmark hospitals was 65% (95%CI 63%‐66%). However, after adjusting for case mix, the difference in ACT utilization between benchmark and non‐benchmark populations was significantly smaller.

Conclusions

We did not find any system‐level factors associated with the utilization of ACT. Our results suggest that the observed variation in hospital ACT rate is not significantly different from variation due to chance alone. Using the “pared‐mean” approach may significantly overestimate optimal treatment rates if case mix is not considered.

Advances in decoding breast cancer brain metastasis

The past decade has witnessed impressive advances in cancer treatment ushered in by targeted and immunotherapies. However, with significantly prolonged survival, upon recurrence, more patients become inflicted by brain metastasis, which is mostly refractory to all currently available therapeutic regimens. Historically, brain metastasis is an understudied area in cancer research, partly due to the dearth of appropriate experimental models that closely simulate the special biological features of metastasis in the unique brain environment and to the sophistication of techniques required to perform in-depth studies of the extremely complex and challenging brain metastasis. Yet, with increasing clinical demand for more effective treatment options, brain metastasis research has rapidly advanced in recent years. The present review spotlights the recent major progresses in basic and translational studies of brain metastasis with focuses on new animal models, novel imaging technologies, omics "big data" resources, and some new and exciting biological insights on brain metastasis.