Chemotherapy with or Without Definitive Radiation Therapy in Inoperable Pancreatic Cancer

Analysis of the cost-effectiveness of proton beam therapy for unresectable pancreatic cancer in Japan

BACKGROUND

Proton beam therapy (PBT) has recently been included in Japan's social health insurance benefits package. This study aimed to determine the cost-effectiveness of PBT for unresectable, locally advanced pancreatic cancer (LAPC) as a replacement for conventional photon radiotherapy (RT).

METHODS

We estimated the incremental cost-effectiveness ratio (ICER) of PBT as a replacement for three-dimensional conformal RT (3DCRT), a conventional photon RT, using clinical evidence in the literature and expense complemented by expert opinions. We used a decision tree and an economic and Markov model to illustrate the disease courses followed by LAPC patients. Effectiveness was estimated as quality-adjusted life years (QALY) using utility weights for the health state. Social insurance fees were calculated as the costs. The stability of the ICER against the assumptions made was appraised using sensitivity analyses.

RESULTS

The effectiveness of PBT and 3DCRT was 1.67610615 and 0.97181271 QALY, respectively. The ICER was estimated to be ¥5,376,915 (US$46,756) per QALY. According to the suggested threshold for anti-cancer therapy from the Japanese authority of ¥7,500,000 (US$65,217) per QALY gain, such a replacement would be considered cost-effective. The one-way and probabilistic sensitivity analyses demonstrated stability of the base-case ICER.

CONCLUSION

PBT, as a replacement for conventional photon radiotherapy, is cost-effective and justifiable as an efficient use of finite healthcare resources. Making it a standard treatment option and available to every patient in Japan is socially acceptable from the perspective of health economics.

Survival Outcomes and Failure Patterns in Patients with Inoperable Non-Metastatic Pancreatic Cancer Treated with Definitive Radiotherapy

This study investigated the long-term results, failure patterns, and prognostic factors of patients with initially inoperable non-metastatic pancreatic cancer (PC) receiving definitive radiotherapy (RT). Between January 2016 and December 2020, a total of 168 non-metastatic PC patients, who were surgically unresectable or medically inoperable, were enrolled to receive definitive RT, with or without chemotherapy. Overall survival (OS) and progression-free survival (PFS) were evaluated using the Kaplan-Meier method with a log-rank test. The cumulative incidence of locoregional and distant progression was estimated using the competing risks model. The Cox proportional-hazards model was used to determine the influence of prognostic variables on OS. With a median follow-up of 20.2 months, the median OS (mOS) and median PFS (mPFS) from diagnosis were 18.0 months [95% confidence interval (CI), 16.5-21.7 months] and 12.3 months (95% CI, 10.2-14.3 months), respectively. The mOS and mPFS from RT were 14.3 months (95% CI, 12.7-18.3 months) and 7.7 months (95% CI, 5.5-12.0 months), respectively. The corresponding 1-year, 2-year, and 3-year OS from diagnosis and RT were 72.1%, 36.6%, and 21.5% as well as 59.0%, 28.8%, and 19.0%, respectively. In a multivariate analysis, stage I-II (p = 0.032), pre-RT CA19-9 ≤ 130 U/mL (p = 0.011), receiving chemotherapy (p = 0.003), and a biologically effective dose (BED₁₀) > 80 Gy (p = 0.014) showed a significant favorable influence on OS. Among the 59 available patients with definite progression sites, the recurrences of local, regional, and distant progression were 33.9% (20/59), 18.6% (11/59), and 59.3% (35/59), respectively. The 1-year and 2-year cumulative incidences of locoregional progression after RT were 19.5% (95% CI, 11.5-27.5%) and 32.8% (95% CI, 20.8-44.8%), respectively. Definitive RT was associated with long-term primary tumor control, resulting in superior survival in patients with inoperable non-metastatic PC. Further prospective randomized trials are warranted to validate our results in these patients.

CT perfusion as a potential biomarker for pancreatic ductal adenocarcinoma during routine staging and restaging

PURPOSE

To evaluate the significance of CT perfusion parameters predicting response to neoadjuvant therapy in patients with pancreatic ductal adenocarcinoma (PDAC).

MATERIALS AND METHODS

Seventy patients with PDAC prospectively had CT perfusion acquisition incorporated into baseline multiphase staging CT. Twenty-eight who were naïve to therapy were retained for further investigation. Perfusion was performed 5-42.5 s after contrast, followed by parenchymal and portal venous phases. Blood flow (BF), blood volume (BV), and permeability surface area product (PS) were calculated using deconvolution algorithms. Patients were categorized as responders or non-responders per RECIST 1.1. Perfusion variables with AUC ≥ 0.70 in differentiating responders from non-responders were retained. Logistic regression was used to assess associations between baseline perfusion variables and response.

RESULTS

18 of 28 patients showed favorable response to therapy. Baseline heterogeneity variables in tumor max ROI were higher in non-responders than responders [median BF coefficient of variation (CV) 0.91 vs. 0.51 respectively, odds ratio (OR) 6.8 per one standard deviation (1-SD) increase, P = 0.047; median PS CV 1.6 vs. 0.68, OR 3.9 per 1-SD increase, P = 0.047; and median BV CV 0.75 vs. 0.54, OR = 4.0 per 1-SD increase, P = 0.047]. Baseline BV mean in tumor center was lower in non-responders than responders (median BV mean: 0.74 vs. 2.9 ml/100 g respectively, OR 0.28 per 1-SD increase, P = 0.047).

CONCLUSION

For patients with PDAC receiving neoadjuvant therapy, lower and more heterogeneous perfusion parameters correlated with an unfavorable response to therapy. Such quantitative information can be acquired utilizing a comprehensive protocol interleaving perfusion CT acquisition with standard of care multiphase CT scans using a single contrast injection, which could be used to identify surgical candidates and predict outcome.

Contemporary use and outcomes of radiation and chemotherapy for unresectable pancreatic cancer

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This study examines 5,624 patients with unresectable pancreatic cancer.

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Across “real-world” US practice, overall use of radiation treatment (RT) has declined.

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Among those receiving RT, stereotactic body radiation treatment (SBRT) increased.

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Contemporary risks of gastrointestinal complications after SBRT have decreased.

Background

We assessed radiation treatment (RT) use and complications for unresectable pancreatic cancer in the US, comparing conventionally fractionated (CFRT) and stereotactic body radiation treatment (SBRT) to inform real-world expected outcomes and practice.

Material and Methods

We analyzed 5,624 patients with non-metastatic, unresectable pancreatic cancer (2,522 older patients age > 65, diagnosed 2006–2013 in Medicare linked data; and 3,102 younger patients age < 65, diagnosed 2006–2016 in MarketScan data), comparing CFRT vs. SBRT vs. chemotherapy alone. Cochran-Armitage tested temporal trends. Fisher’s Exact Test and proportional hazards models compared gastrointestinal (GI) complications. Healthcare payments (Consumer Price Index adjusted to 2015) through 12 months were compared using generalized linear regression models with log link and gamma distribution.

Results

RT use declined from 55% to 45% of older patients (2006–2013) and 52% to 47% of younger patients (2006–2016) (Ptrend < 0.001 both). Among RT patients, SBRT use increased to 10% of older patients and 12% of younger patients in the most recent years (Ptrend = 0.04 and < 0.001 respectively). Addition of RT was associated with more frequent GI bleeds, strictures, and fistulas (Δ= +3% to 9% excess events, all P ≤ 0.05). Temporal patterns suggested decreasing complications over time (Ptrend = 0.05 and 0.05 for older and younger patients). Among younger patients, there was no difference in GI complications for SBRT vs. CFRT (P > 0.05, all comparisons). Among older patients, increased complications were seen for SBRT in 1–4 fractions vs. CFRT (P < 0.05), but not SBRT in 5 fractions (P = 0.72). Healthcare payments were greatest for SBRT when compared with CFRT or chemotherapy under US Medicare (P < 0.001) and employer-based insurance (P < 0.001).

Conclusion

Real-world treatment has shifted toward more selectivity for RT in unresectable pancreatic cancer. However, SBRT uptake and improving trends in complications profiles represent opportunities to optimize current use and benefit. Findings are applicable to inform future comparative and cost effectiveness models of RT for this disease.

Evolving pancreatic cancer treatment: From diagnosis to healthcare management

The prognosis of pancreatic ductal adenocarcinoma is still the worst among solid tumors. In this review, a panel of experts addressed the main unanswered questions about the clinical management of this disease, with the aim of providing practical decision support for physicians. On the basis of the evidence available from the literature, the main topics concerning pancreatic cancer are discussed: the diagnosis, as the need for a pathological characterization and the role for germ-line and somatic molecular profiling; the therapeutic management of resectable disease, as the role of upfront surgery or neoadjuvant chemotherapy, the post-operative restaging and the optimal timing foradjuvant chemotherapy, the management of the borderline resectable and locally advanced disease; the metastatic disease and the role of surgery for the management of patients with isolated metastasis and the use of biomarkers of metastatic potential; the role of supportive care and the healthcare management of pancreatic ductal adenocarcinoma.

Feasibility of wide detector CT perfusion imaging performed during routine staging and restaging of pancreatic ductal adenocarcinoma

PURPOSE

To evaluate the feasibility of CT perfusion performed during routine multiphase contrast-enhanced CT on a 160 mm wide-coverage 256-slice scanner in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Fifty-seven patients had a CT perfusion acquisition during their routine multiphase CT. Perfusion was performed 5 to 42.5 s (15 passes at 2.5 s intervals) after intravenous contrast administration (4.2-5 ml/s), followed by pancreatic parenchymal and portal venous phases for clinical interpretation. Perfusion maps were generated and blood flow (BF), blood volume (BV), and permeability surface area product (PS) for tumor and uninvolved pancreas were calculated using deconvolution algorithms and compared to existing similar publications. Radiation dose information was recorded and size-specific dose estimate (SSDE) was calculated using body dimensions.

RESULTS

Diagnostic quality of standard images was unaffected by performing the perfusion acquisition. Average tumor center BF was 20.8 ± 12.1 ml/100 g/min, BV 2.5 ± 2.1 ml/100 g and PS 15.5 ± 39.4 ml/100 g/min. Average pancreas BF was 90.8 ± 50.2 ml/100 g/min, BV 11.9 ± 4.3 ml/100 g and PS 33.6 ± 27.7 ml/100 g/min. For the perfusion acquisition, mean SSDE was 57 ± 11 mGy, CTDI_vol 43 ± 6 mGy and DLP 685 ± 100 mGy-cm.

CONCLUSION

Adding a perfusion CT acquisition to standard pancreatic CT protocol is feasible using a wide-detector 256-slice CT scanner and adds quantitative information while maintaining diagnostic quality of the standard of care examination. This novel protocol adds no time or cost to the examination and yields perfusion parameters that are comparable to existing literature using a separate dedicated perfusion protocol.

Clinical Practice Guidelines for Diagnosis, Treatment and Follow-Up of Exocrine Pancreatic Ductal Adenocarcinoma: Evidence Evaluation and Recommendations by the Italian Association of Medical Oncology (AIOM)

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related death in women (7%) and the sixth in men (5%) in Italy, with a life expectancy of around 5% at 5 years. From 2010, the Italian Association of Medical Oncology (AIOM) developed national guidelines for several cancers. In this report, we report a summary of clinical recommendations of diagnosis, treatment and follow-up of PDAC, which may guide physicians in their current practice. A panel of AIOM experts in upper gastrointestinal cancer malignancies discussed the available scientific evidence supporting the clinical recommendations.

Nab-paclitaxel plus gemcitabine as first-line treatment for advanced pancreatic cancer: a systematic review and meta-analysis

To evaluate the effectiveness of nab-paclitaxel plus gemcitabine (NG) as a first-line treatment for advanced pancreatic cancer. A meta-analysis was performed to assess the impact on the objective response rate (ORR), survival rate and grade 3/4 adverse events. Of the 2,056 patients included from 26 studies, the median overall survival ranged from 6.9 months to 24.7 months, with a 1-year survival rate of 45.2% (95%CI: 35.8% -54.5%). The 6-month progression-free survival rate was 41.0% (95%CI: 30.5% - 51.4%), and the ORR was 31.6% (95%CI: 26.7% - 36.6%). Fifty locally advanced pancreatic cancer (LAPC) patients underwent surgery and had an R0 resection rate of 52.0%. No death was caused by toxicity, and 1,329 grade 3/4 adverse events were reported in 1,353 patients. NG has been proven to reduce tumours with an acceptable toxicity profile in metastatic pancreatic cancer. This analysis further demonstrates the efficacy and safety of NG for treating LAPC.