Neurocognitive Outcomes in Multiethnic Pediatric Brain Tumor Patients Treated With Proton Versus Photon Radiation

BACKGROUND

We analyzed post-radiation (RT) neurocognitive outcomes in an ethnically diverse pediatric brain tumor population undergoing photon radiotherapy (XRT) and proton radiotherapy (PRT).

PROCEDURE

Post-RT neurocognitive outcomes from 49 pediatric patients (37% Hispanic/Latino) with primary brain tumors were analyzed. Tests included cognitive outcomes, behavioral outcomes, and overall intelligence. For each outcome, proportion of patients with cognitive impairment (scores <1.5 SD) was calculated. The Fisher exact tests compared proportion of patients with impairment and t tests compared T-scores between XRT (n=32) and PRT (n=17) groups. Linear regression assessed associations between radiation modality and outcomes.

RESULTS

Median follow-up was 3.2 and 1.8 years in the XRT and PRT groups, respectively. The median RT dose was 54.0 Gy. We found impairment in 16% to 42% of patients across most neurocognitive domains except executive function. There was no difference in scores between XRT and PRT groups. Regression analyses revealed no association of neurocognitive outcomes with radiation modality. Non-Hispanic patients had better Verbal Comprehension Index and General Ability Index scores than Hispanic patients ( P <0.05).

CONCLUSIONS

Among pediatric patients with brain tumors receiving RT, all cognitive domains were affected except executive function. Radiation modality was not associated with neurocognitive outcomes. Hispanic patients may be more vulnerable to posttreatment cognitive effects that warrant further study.

Metastasis and Mortality in Men With Low- and Intermediate-Risk Prostate Cancer on Active Surveillance

BACKGROUND

Active surveillance (AS) is a safe treatment option for men with low-risk, localized prostate cancer. However, the safety of AS for patients with intermediate-risk prostate cancer remains unclear.

PATIENTS AND METHODS

We identified men with NCCN-classified low-risk and favorable and unfavorable intermediate-risk prostate cancer diagnosed between 2001 and 2015 and initially managed with AS in the Veterans Health Administration. We analyzed progression to definitive treatment, metastasis, prostate cancer-specific mortality (PCSM), and all-cause mortality using cumulative incidences and multivariable competing-risks regression.

RESULTS

The cohort included 9,733 men, of whom 1,007 (10.3%) had intermediate-risk disease (773 [76.8%] favorable, 234 [23.2%] unfavorable), followed for a median of 7.6 years. The 10-year cumulative incidence of metastasis was significantly higher for patients with favorable (9.6%; 95% CI, 7.1%-12.5%; P<.001) and unfavorable intermediate-risk disease (19.2%; 95% CI, 13.4%-25.9%; P<.001) than for those with low-risk disease (1.5%; 95% CI, 1.2%-1.9%). The 10-year cumulative incidence of PCSM was also significantly higher for patients with favorable (3.7%; 95% CI, 2.3%-5.7%; P<.001) and unfavorable intermediate-risk disease (11.8%; 95% CI, 6.8%-18.4%; P<.001) than for those with low-risk disease (1.1%; 95% CI, 0.8%-1.4%). In multivariable competing-risks regression, favorable and unfavorable intermediate-risk patients had significantly increased risks of metastasis and PCSM compared with low-risk patients (all P<.001).

CONCLUSIONS

Compared with low-risk patients, those with favorable and unfavorable intermediate-risk prostate cancer managed with AS are at increased risk of metastasis and PCSM. AS may be an appropriate option for carefully selected patients with favorable intermediate-risk prostate cancer, though identification of appropriate candidates and AS protocols should be tested in future prospective studies.

Post-treatment Neuroendocrine Outcomes Among Pediatric Brain Tumor Patients: Is there a difference between proton and photon therapy?

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Endocrinopathies were common among pediatric brain tumor survivors.

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Proton craniospinal irradiation had a lower risk of hypothyroidism.

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Non-medulloblastoma patients were less likely to develop endocrinopathies.

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Non-medulloblastoma patients were less likely to need hormone replacement therapy.

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Sex hormone deficiency was not observed in the proton cohort.

Purpose

Pediatric brain tumor patients are vulnerable to radiotherapy (RT) sequelae including endocrinopathies. We compared post-RT neuroendocrine outcomes between pediatric brain tumor patients receiving photons (XRT) versus protons (PRT).

Methods

Using a prospectively maintained single-institution database, we analyzed 112 pediatric primary brain tumor patients (80 XRT, 32 PRT) from 1996 to 2019. Patient/treatment characteristics and endocrinopathy diagnoses (growth hormone deficiency [GHD], sex hormone deficiency [SHD], hypothyroidism, and requirement of hormone replacement [HRT]) were obtained via chart review. Univariable/multivariable logistic regression identified neuroendocrine outcome predictors. Time-adjusted propensity score models accounted for treatment type. Craniospinal irradiation (CSI) patients were evaluated as a sub-cohort.

Results

Median follow-up was 6.3 and 4.4 years for XRT and PRT patients respectively. Medulloblastoma was the most common histology (38%). Half of patients (44% in XRT, 60% in PRT) received CSI. Common endocrinopathies were GHD (26% XRT, 38% PRT) and hypothyroidism (29% XRT, 19% PRT). CSI cohort PRT patients had lower odds of hypothyroidism (OR 0.16, 95% CI[0.02–0.87], p = 0.045) on multivariable regression and propensity score analyses. There were no significant differences in endocrinopathies in the overall cohort and in the odds of GHD or HRT within the CSI cohort. SHD developed in 17.1% of the XRT CSI group but did not occur in the PRT CSI group.

Conclusion

Endocrinopathies were common among pediatric brain tumor survivors. Among CSI patients, PRT was associated with lower risk of hypothyroidism, and potentially associated with lower incidence of SHD. Future studies should involve collaborative registries to explore the survivorship benefits of PRT.

Active surveillance for intermediate-risk prostate cancer in African American and non-Hispanic White men

BACKGROUND

The safety of active surveillance (AS) for African American men compared with non-Hispanic White (White) men with intermediate-risk prostate cancer is unclear.

METHODS

The authors identified patients with modified National Comprehensive Cancer Network favorable ("low-intermediate") and unfavorable ("high-intermediate") intermediate-risk prostate cancer diagnosed between 2001 and 2015 and initially managed with AS in the Veterans Health Administration database. They analyzed definitive treatment, disease progression, metastases, prostate cancer-specific mortality (PCSM), and all-cause mortality by using cumulative incidences and multivariable competing-risks (disease progression, metastasis, and PCSM) or Cox (all-cause mortality) regression.

RESULTS

The cohort included 1007 men (African Americans, 330 [32.8%]; Whites, 677 [67.2%]) followed for a median of 7.7 years; 773 (76.8%) had low-intermediate-risk disease, and 234 (23.2%) had high-intermediate-risk disease. The 10-year cumulative incidences of definitive treatment were not significantly different (African Americans, 83.5%; 95% confidence interval [CI], 78.5%-88.7%; Whites, 80.6%; 95% CI, 76.6%-84.4%; P = .17). Among those with low-intermediate-risk disease, there were no significant differences in the 10-year cumulative incidences of disease progression (African Americans, 46.8%; 95% CI, 40.0%-53.3%; Whites, 46.9%; 95% CI, 42.1%-51.5%; P = .91), metastasis (African Americans, 7.1%; 95% CI, 3.7%-11.8%; Whites, 10.8%; 95% CI, 7.6%-14.6%; P = .17), or PCSM (African Americans, 3.8%; 95% CI, 1.6%-7.5%; Whites, 3.8%; 95% CI, 2.0%-6.3%; P = .69). In a multivariable regression including the entire cohort, African American race was not associated with increased risks of definitive treatment, disease progression, metastasis, PCSM, or all-cause mortality (all P > .30).

CONCLUSIONS

Outcomes in the Veterans Affairs Health System were similar for African American and White men treated for low-intermediate-risk prostate cancer with AS.

Impact of Radiation on Cardiovascular Outcomes in Older Resectable Esophageal Cancer Patients With Medicare

OBJECTIVES

Preoperative radiotherapy improves outcomes for operable esophageal cancer patients, though the proximity of the heart to the esophagus puts patients at risk of radiation-induced cardiovascular disease. This study characterizes the impact of radiotherapy and different radiation techniques on cardiovascular morbidity among a cohort of esophageal cancer patients.

MATERIALS AND METHODS

We identified 1125 patients aged 65 and older diagnosed between 2000 and 2011 with esophageal cancer who received surgery alone, or surgery preceded by either preoperative chemotherapy or preoperative chemoradiation from the Surveillance Epidemiology and End Results (SEER)-Medicare database. We used Medicare claims to identify severe perioperative and late cardiovascular events. Multivariable logistic regression and Fine-Gray models were used to determine the effect of presurgery treatment on the risk of perioperative and late cardiovascular disease.

RESULTS

Preoperative chemotherapy or chemoradiation did not significantly increase the risk of perioperative cardiovascular complications compared with surgery alone. Patients treated with preoperative chemoradiation had a 36% increased risk of having a late cardiovascular event compared with patients treated with surgery alone (subdistribution hazard ratio [SDHR]: 1.36; P=0.035). There was no significant increase in late cardiovascular events among patients treated with preoperative chemotherapy (SDHR: 1.18; P=0.40). Among patients treated with preoperative chemoradiation, those receiving intensity modulated radiotherapy had a 68% decreased risk of having a late cardiovascular event compared with patients receiving conventional radiation (SDHR: 0.32; P=0.007).

CONCLUSIONS

This study demonstrates an increased risk of cardiovascular complications among operative esophageal cancer patients treated with preoperative chemoradiation, though these risks might be reduced with more cardioprotective radiation techniques such as intensity modulated radiotherapy.

Cost-effectiveness of Nivolumab-Ipilimumab Combination Therapy for the Treatment of Advanced Non-Small Cell Lung Cancer

IMPORTANCE

Treatment with nivolumab-ipilimumab combination therapy was found to improve overall survival compared with chemotherapy among patients with advanced non-small cell lung cancer (NSCLC) in the CheckMate 227 clinical trial. However, these drugs are substantially more expensive than chemotherapy and, given the high incidence of advanced NSCLC, the incorporation of dual immune checkpoint inhibitors into the standard of care could have substantial economic consequences.

OBJECTIVE

To assess whether nivolumab-ipilimumab combination therapy is a cost-effective first-line treatment for patients with advanced NSCLC.

DESIGN, SETTING, AND PARTICIPANTS

This economic evaluation designed a Markov model to compare the cost-effectiveness of nivolumab-ipilimumab combination therapy with platinum-doublet chemotherapy as first-line treatment for patients with advanced NSCLC. The Markov model was created to simulate patients with advanced NSCLC who were receiving either nivolumab-ipilimumab combination therapy or platinum-doublet chemotherapy. Transition probabilities, including disease progression, survival, and treatment toxic effects, were derived using data from the CheckMate 227 clinical trial. Costs and health utilities were obtained from published literature. Data analyses were conducted from November 2019 to September 2020.

EXPOSURES

Nivolumab-ipilimumab combination therapy.

MAIN OUTCOMES AND MEASURES

The primary study outcomes were quality-adjusted life-years (QALYs) and cost in 2020 US dollars. Cost-effectiveness was measured using an incremental cost-effectiveness ratio (ICER), with an ICER less than $100 000 per QALY considered cost-effective. Model uncertainty was assessed with 1-way and probabilistic sensitivity analyses.

RESULTS

Treatment with nivolumab-ipilimumab combination therapy was associated with an increase in overall cost of $201 900 and improved effectiveness of 0.50 QALYs compared with chemotherapy, yielding an ICER of $401 700 per QALY. The study model was sensitive to the cost and duration of immunotherapy. Treatment with nivolumab-ipilimumab combination therapy became cost-effective when monthly treatment costs were reduced from $26 425 to $5058 (80.9% reduction) or when the maximum duration of immunotherapy was reduced from 24.0 months to 1.4 months. The model was not sensitive to assumptions about survival or programmed cell death 1 ligand 1 status. A probabilistic sensitivity analysis indicated that, at a willingness-to-pay threshold of $100 000 per QALY, nivolumab-ipilimumab combination therapy was less cost-effective than chemotherapy 99.9% of the time.

CONCLUSIONS AND RELEVANCE

In this study, first-line treatment with nivolumab-ipilimumab combination therapy was not found to be cost-effective at current prices despite clinical trial data indicating that this regimen increases overall survival among patients with advanced NSCLC.

Cost effectiveness of combination ipilimumab-nivolumab in advanced non-small-cell lung cancer

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Background: The combination of nivolumab and ipilimumab was found to improve overall survival compared to chemotherapy in patients with advanced non-small-cell lung cancer (NSCLC) in the Checkmate 227 trial. However, nivolumab and ipilimumab are significantly more expensive than chemotherapy, and given the high incidence of advanced lung cancer, incorporating dual checkpoint inhibitors into the standard of care could have substantial economic consequences. In this study, we evaluated the cost effectiveness of combination ipilimumab and nivolumab for the treatment of advanced NSCLC. Methods: We designed a Markov model simulating the three treatment arms of the Checkmate 227 trial: nivolumab plus ipilimumab, nivolumab monotherapy, and chemotherapy. Transition probabilities, such as disease progression, survival, and treatment toxicities, were derived from trial data. Costs (in 2019 United States dollars) and health utilities were estimated from published literature. Incremental cost-effectiveness ratios (ICERs), expressed as dollar per quality-adjusted life-year (QALY), were calculated, with results less than $100,000/QALY considered cost-effective from a healthcare payer perspective. We assessed model uncertainty with one-way and probabilistic sensitivity analyses. Results: In our base-case model, nivolumab and ipilimumab combination therapy increased overall cost by $227,700 and improved effectiveness by 0.55 QALY compared to chemotherapy, resulting in an ICER of $413,400/QALY. Nivolumab monotherapy increased overall cost by $98,500 and improved effectiveness by 0.05 QALY compared to chemotherapy, resulting in an ICER of $1,885,400/QALY. Our model was most sensitive to both the cost and duration of dual immunotherapy. Combination immunotherapy became cost effective at an ICER under $100,000/QALY if monthly costs of treatment were reduced from $26,586 to $8,844 (a 67% reduction) or if maximum allowed duration of immunotherapy was reduced from 24 to 4 months. The model was not sensitive to assumptions about survival differences between the study arms. Probabilistic sensitivity analysis showed that at a willingness-to-pay threshold of $100,000/QALY, dual immunotherapy was less cost-effective than chemotherapy 99.99% of the time. Conclusions: Combination nivolumab and ipilimumab immunotherapy is not cost-effective at current prices despite increasing overall survival for patients with advanced NSCLC.

Cost-effectiveness of combined atezolizumab/nab-paclitaxel for advanced triple-negative breast cancer

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Background: The IMpassion 130 trial found prolonged progression-free and overall survival among PD-L1-positive, advanced triple-negative breast cancer (TNBC) patients receiving atezolizumab and nab-paclitaxel versus nab-paclitaxel alone. These results were the basis of the first FDA approval of a breast cancer immunotherapeutic agent. With the high cost of combined therapy we present a cost-effectiveness analysis of the addition of atezolizumab to nab-paclitaxel for the treatment of advanced TNBC in PD-L1-positive patients. Methods: We constructed a Markov model to simulate cancer progression, survival, and toxicity in advanced TNBC patients receiving atezolizumab and nab-paclitaxel compared to nab-paclitaxel alone. Transition probabilities were derived from the IMpassion 130 trial, while costs (in 2019 US dollars) and health utilities were estimated from the literature. Cost effectiveness was assessed with incremental cost-effectiveness ratios (ICERs), expressed as dollar per quality-adjusted life-year (QALY), with values of less than $100,000/QALY considered cost effective. We conducted one-way and probabilistic sensitivity analyses to examine model uncertainty. Results: Our base-case model found that treatment with atezolizumab and nab-paclitaxel increased overall cost by $120,800 and improved effectiveness by 0.11 QALYs compared with nab-paclitaxel alone, leading to an ICER of $1,101,000/QALY. The base-case model was not sensitive to any single variable. Women in the combined atezolizumab and nab-paclitaxel arm spent more time with stable disease before progression and with progressive disease before death compared to those treated with nab-paclitaxel alone. In our base-case analysis the addition of atezolizumab was not cost effective at any price of atezolizumab secondary to the high costs of stable and progressive disease. If we assumed lower costs of stable disease and progression, our model became sensitive to the cost of atezolizumab. A probabilistic sensitivity analysis found that adding atezolizumab would be cost ineffective 99.9% of the time at a willingness-to-pay of $100,000/QALY. Conclusions: Despite improved clinical outcomes, the addition of atezolizumab would not be considered cost effective in part due to the high costs of stable disease and disease progression among women with advanced TNBC. Novel therapeutics in this costly patient cohort will need to bend the cost curve of stable and progressive disease before becoming cost effective at thresholds acceptable by today’s standards.