Locoregional Treatment of Metastatic Pancreatic Cancer Utilizing Resection, Ablation and Embolization: A Systematic Review

Addition of Metastasis-Directed Therapy to Systemic Therapy for Oligometastatic Pancreatic Ductal Adenocarcinoma (EXTEND): A Multicenter, Randomized Phase II Trial

PURPOSE

The EXTEND trial tested the hypothesis that adding comprehensive metastasis-directed therapy (MDT) to chemotherapy would improve progression-free survival (PFS) over chemotherapy alone among patients with oligometastatic pancreatic ductal adenocarcinoma (PDAC).

METHODS

EXTEND (ClinicalTrials.gov identifier: NCT03599765) is a multicenter, phase II basket trial randomly assigning patients with ≤five metastases 1:1 to MDT plus systemic therapy versus systemic therapy. Disease progression was defined by radiologic criteria (RECIST v1.1), clinical progression, or death. The primary end point was PFS in the per-protocol population, evaluated after all patients achieved at least 6 months of follow-up. Exploratory end points included systemic immune response measures.

RESULTS

Between March 19, 2019, and February 13, 2023, 41 patients were randomly assigned and 40 were eligible for the primary analysis of PFS (19 patients in the MDT arm; 21 patients in the control arm). At a median follow-up time of 17 months, the median PFS time was 10.3 months (95% CI, 4.6 to 14.0) in the MDT arm versus 2.5 months (95% CI, 1.7 to 5.1) in the control arm. PFS was significantly improved by the addition of MDT to systemic therapy (P = .030 for stratified log-rank test) with a hazard ratio of 0.43 (95% CI, 0.20 to 0.94). No grade ≥3 or greater adverse events related to MDT were observed. Systemic immune activation events were associated with MDT and correlated with improved PFS.

CONCLUSION

This study supports the addition of MDT to systemic therapy for patients with oligometastatic PDAC. Induction of systemic immunity is a possible mechanism of benefit. These results warrant confirmatory trials to refine treatment strategy and provide external validation.

Effect of chemotherapy on prognosis in patients with primary pancreatic signet ring cell carcinoma: A large real-world study based on machine learning

BACKGROUND

Primary pancreatic signet ring cell carcinoma (PSRCC), an extremely rare histologic variant of pancreatic cancer, has a poor prognosis. This study aimed to investigate the prognostic value of chemotherapy in PSRCC.

METHODS

Patients with PSRCC between 2000 and 2019 were identified using the Surveillance Epidemiology and End Results (SEER) database. The main outcomes in this study were cancer-specific survival (CSS) and overall survival (OS). The baseline characteristics of patients were compared using Pearson's Chi-square test. Kaplan-Meier analysis was used to generate the survival curves. Least absolute shrinkage and selection operator (LASSO), univariate and multivariate Cox regression models, and Random Survival Forest model were used to analyze the prognostic variables for OS and CSS. The variance inflation factors (VIFs) were used to analyze whether there was an overfitting problem.

RESULTS

A total of 588 patients were identified. Chemotherapy was an independent prognostic factor for OS and CSS, and significantly associated with OS (HR = 0.33, 95% CI = 0.27-0.40, P <0.001) and CSS (HR = 0.32, 95% CI = 0.26-0.39, P <0.001).

CONCLUSIONS

Chemotherapy showed beneficial effects on OS and CSS in patients with PSRCC and should be recommended in clinical practice.

Outcomes of lung oligometastasis in pancreatic cancer

OBJECTIVE

Pancreatic cancer with lung oligometastasis may have favourable overall survival. The aim of this study was to evaluate outcomes of pancreatic cancer with lung oligometastases including both synchronous and metachronous metastases.

METHODS

Consecutive pancreatic cancer patients with lung metastasis treated at our institution between February 2015 and December 2021 were identified from our prospectively maintained database. Clinical characteristics and outcomes were compared and analysed according to the extent of lung metastases. Predictors for overall survival were analysed using the Cox proportional hazards model.

RESULTS

A totoal of 171 patients were included (oligometastasis/polymetastasis/multi-organ metastasis: 34/50/87). Patients with oligometastases were more likely to undergo surgical resection (41% vs. 0% vs. 2%) and showed a longer median overall survival (41.3 vs. 17.6 vs. 13.1 months) compared with those with other types of metastases. Oligometastasis (hazard ratio, 0.43; 95% confidence interval, 0.24-0.76; P = 0.004) was identified as an independent factor predicting favourable overall survival in patients with lung-only metastasis. Disease status (synchronous vs. metachronous) was not associated with survival in patients with oligometastasis (29.4 vs. 41.3 months, P = 0.527) and polymetastasis (17.9 vs. 16.7 months, P = 0.545). Selected patients who underwent surgical resection showed a median overall survival of 52.7 months.

CONCLUSIONS

Patients with lung oligometastases presented a favourable prognosis. Surgical resection in selected patients was associated with a long median overall survival.

Defining oligometastatic pancreatic cancer: a systematic review and critical synthesis of consensus

BACKGROUND

Small retrospective series suggest that local consolidative treatment (LCT) may improve survival in oligometastatic pancreatic ductal adenocarcinoma (PDAC). However, no uniform definition of oligometastatic disease (OMD) in PDAC exists; this impedes meaningful conclusions.

PATIENTS AND METHODS

A systematic literature search using PubMed, Web of Science, and Cochrane CENTRAL registries for studies and protocols reporting on definitions and/or LCT of OMD in PDAC was performed. The primary endpoint was the definition of OMD. Levels of agreement were categorized as consensus (≥75% agreement between studies), fair agreement (50%-74%), and absent/poor agreement (<50%).

RESULTS

After screening of 5374 abstracts, the full text of 218 studies was assessed, of which 76 were included in the qualitative synthesis. The majority of studies were retrospective (n = 66, 87%), two were prospective studies and eight were study protocols. Studies investigated mostly liver (n = 38, 51%) and lung metastases (n = 15, 20%). Across studies, less than one-half (n = 32, 42%) reported a definition of OMD, while 44 (58%) did not. Involvement was limited to a single organ (consensus). Additional criteria for defining OMD were the number of lesions (consensus), metastatic site (poor agreement), metastatic size (poor agreement), treatment possibilities (poor agreement), and biomarker response (poor agreement). Liver OMD could involve three or fewer lesions (consensus) and synchronous disease (fair agreement), while lung metastases could involve two or fewer lesions and metachronous disease (consensus). The large majority of studies were at a high risk of bias or did not include any control groups.

CONCLUSION

Definitions of OMD were not used or varied widely between studies hampering across-study comparability and highlighting an unmet need for a consensus. The present study is part of a multistep process that aims to develop an interdisciplinary consensus on OMD in pancreatic cancer.

Sequential therapy for pancreatic cancer patients with synchronous oligo-hepatic metastatic lesions

BACKGROUND

Treatments for patients suffering from pancreatic cancer with oligo-hepatic metastasis have always been a cause of certain controversy. Herein, we reported 15 pancreatic cancer patients with oligo-hepatic metastasis who accepted sequential therapy of chemotherapy, radiofrequency ablation (RFA), and radical resection of the primary tumor.

METHODS

A total of 87 pancreatic cancer patients with synchronous oligo-metastatic hepatic lesions who received treatments in the 2nd Affiliated Hospital of Zhejiang University between January 2017 and July 2020 were enrolled. The chemotherapy regimens included modified folfirinox (54/87) and gemcitabine plus nab-paclitaxel (33/87). Test of blood tumor markers and contrast-enhanced computed tomography (CT) or magnetic resonance (MR) scan was performed at diagnosis and after eight weeks of chemotherapy.

RESULTS

Thirty-five patients received just chemotherapy because of poor reaction to the first round of chemotherapy(Overall survival (OS), 6.47±1.80 months); 15 patients reassessed as stable disease (SD)/partial response (PR) continued chemotherapy (OS, 10.35±3.15); nine patients reassessed as progressive disease (PD) after RFA and continued chemotherapy (OS, 10.90±2.60). The primary tumors in 13 patients were unresectable after chemotherapy and RFA (OS, 12.92±2.47), while 15 patients completed the sequential therapy of chemotherapy, radio-frequency ablation, and radical resection (OS, 16.76±6.55).

CONCLUSIONS

Sequential chemotherapy and RFA is a good treatment strategy to select the best candidates for surgical treatment among patients with pancreatic cancer with oligo-hepatic metastasis.

An Ionic Liquid Ablation Agent for Local Ablation and Immune Activation in Pancreatic Cancer

Pancreatic ductal adenocarcinoma rapidly acquires resistance to chemotherapy, remaining a fatal disease. Immunotherapy is one of the breakthroughs in cancer treatment, which includes immune checkpoint inhibitors, chimeric antigen receptor T-cell immunotherapy, and neoantigen vaccines. However, immunotherapy has not achieved satisfactory results in the treatment of pancreatic cancer. Immunogenic death comprises proinflammatory cell death, which provides a way to enhance tumor immunogenicity and promote an immune response in solid tumors. Herein, an ionic liquid ablation agent (LAA), synthesized from choline and geranic acid, which triggers necrosis-induced immunotherapy by remodeling an immunosuppressive "cold" tumor to an immune activated "hot" tumor is described. The results indicate that LAA-treated tumor cells can enhance immunogenicity, inducing dendritic cell maturation, macrophage M1 polarization, and cytotoxic T lymphocyte infiltration. The results of the present study provide a novel strategy for solid tumor immunotherapy.

Outcomes of pancreatic cancer with liver oligometastasis

BACKGROUND

Liver oligometastatic pancreatic cancer (PC) may have favorable outcomes. This study aims to evaluate outcomes and factors associated with overall survival (OS) of these patients.

METHODS

We retrospectively investigated consecutive PC patients with liver metastasis treated at our institution between 2013 and 2020. Clinical characteristics and outcomes were compared and analyzed according to the extent of liver metastasis. Cox proportional hazards model was used to identify prognostic factors for OS.

RESULTS

A total of 417 patients were included (multi-organ metastasis/polymetastasis/oligometastasis 174/158/85). Oligometastasis showed a longer OS compared to other types of metastases (7.7 vs 8.2 vs 13.1 months). Age <70 years, performance status of 0, modified Glasgow prognostic score of 0, carbohydrate antigen 19-9 <1000 U/mL were identified as significant prognostic factors for OS. A prognostic index consisting of these four factors successfully stratified the prognosis of these patients (prognostic index; high vs low, 19.9 vs 8.3 months). Highly selected patients who underwent surgical resection showed a median OS of 54.6 months.

CONCLUSIONS

Oligometastasis presented a relatively favorable outcome. Our new prognostic index was useful in stratifying the prognosis of these patients. Multimodal treatment including surgery may have additional survival benefits for highly selected patients.

A population-based study of synchronous distant metastases and prognosis in patients with PDAC at initial diagnosis

Objective

Cancer of the pancreas is a life-threatening condition and has a high distant metastasis (DM) rate of over 50% at diagnosis. Therefore, this study aimed to determine whether patterns of distant metastases correlated with prognosis in pancreatic ductal adenocarcinoma (PDAC) with metastatic spread, and build a novel nomogram capable of predicting the 6, 12, 18-month survival rate with high accuracy.

Methods

We analyzed data from the Surveillance, Epidemiology, and End Results (SEER) database for cases of PDAC with DM. Kaplan-Meier analysis, log-rank tests and Cox-regression proportional hazards model were used to assess the impact of site and number of DM on the cancer-specific survival (CSS) and over survival (OS). A total of 2709 patients with DM were randomly assigned to the training group and validation group in a 7:3 ratio. A nomogram was constructed by the dependent risk factors which were determined by multivariate Cox-regression analysis. An assessment of the discrimination and ability of the prediction model was made by measuring AUC, C-index, calibration curve and decision curve analysis (DCA). In addition, we collected 98 patients with distant metastases at the time of initial diagnosis from Ningbo University Affiliated LiHuili Hospital to verify the efficacy of the prediction model.

Results

There was a highest incidence of liver metastases from pancreatic cancer (2387,74.36%), followed by lung (625,19.47%), bone (190,5.92%), and brain (8,0.25%). The prognosis of liver metastases differed from that of lung metastases, and the presence of multiple organ metastases was associated with poorer prognosis. According to univariate and multivariate Cox-regression analyses, seven factors (i.e., diagnosis age, tumor location, grade of tumor differentiation, T-stage, receipt of surgery, receipt of chemotherapy status, presence of multiple organ metastases) were included in our nomogram model. In internal and external validation, the ROC curves, C-index, calibration curves and DCA were calculated, which confirmed that this nomogram can precisely predict prognosis of PDAC with DM.

Conclusion

Metastatic PDAC patients with liver metastases tended to have a worse prognosis than those with lung metastases. The number of DM had significant effect on the overall survival rate of metastatic PDAC. This study had a high prediction accuracy, which was helpful clinicians to analyze the prognosis of PDAC with DM and implement individualized diagnosis and treatment.

Ablative 5-Fraction Stereotactic MRI-Guided Adaptive Radiotherapy for Oligometastatic Pancreatic Adenocarcinoma

INTRODUCTION

Metastatic pancreatic ductal adenocarcinoma (PDAC) carries a poor prognosis and significant morbidity from local tumor progression. We investigated outcomes among oligometastatic PDAC patients treated with stereotactic magnetic resonance image-guided ablative radiotherapy (SMART) to primary disease.

METHODS

We performed a retrospective multi-institutional analysis of oligometastatic PDAC at diagnosis or with metachronous oligoprogression during induction chemotherapy treated with primary tumor SMART. Outcomes of interest included overall survival (OS), progression-free survival (PFS), freedom from locoregional failure (FFLRF), and freedom from distant failure (FFDF). Acute and late toxicity were reported and in exploratory analyses patients were stratified by the number of metastases, SMART indication, and addition of metastasis-directed therapy.

RESULTS

From 2019 to 2021, 22 patients with oligometastatic PDAC (range: 1-6 metastases) received SMART to the primary tumor with a median follow-up of 11.2 months from SMART. Nineteen patients had de novo synchronous metastatic disease and three had metachronous oligoprogression. Metastasis location most commonly was liver only (40.9%), multiple organs (27.3%), lungs only (13.6%), or abdominal/pelvic nodes (13.6%). All patients received either FOLFIRINOX (64%) or gemcitabine/nab-paclitaxel (36%) followed by SMART (median 50 Gy, 5 fractions) for local control (77%), pain control (14%), or local progression (9%). Additionally, 41% of patients received other metastasis-directed treatments. The median OS from diagnosis and SMART was 23.9 months and 11.6 months, respectively. Calculated from SMART, the median PFS was 2.4 months with 91% of patients having distant progression, and 1-year local control was 68. Two patients (9%) experienced grade 3 toxicities, gastric outlet obstruction, and gastrointestinal bleed without grade 4 or 5 toxicity.

CONCLUSION

There was minimal morbidity of local disease progression after SMART in this cohort of oligometastatic PDAC. As systemic therapy options improve, additional strategies to identify patients who may derive benefits from local consolidation or metastasis-directed therapy are needed.

Survival Benefit of Resection Surgery for Pancreatic Ductal Adenocarcinoma with Liver Metastases: A Propensity Score-Matched SEER Database Analysis

Simple Summary

Pancreatic ductal adenocarcinoma is a devastating illness but guidelines consider it unresectable once metastasized. However, resection of the primary tumor is carried out in select cases and retrospective analyses indicate that this may improve survival. Even so, these analyses are limited to single centers or fail to account for biased patient selection. We overcome these limitations with a propensity score-matched SEER database analysis that reliably demonstrates surgery can extend overall survival. Furthermore, we identify prognostic factors that could aid the selection of patients for randomized controlled trials. Thus, this study paves the way for future work that aims to update treatment guidelines in accordance with surgical developments.

Abstract

Guidelines do not recommend resection surgery for oligometastatic pancreatic ductal adenocarcinoma (PDAC). However, reports in small samples of selected patients suggest that surgery extends survival. Thus, this study aims to gather evidence for the benefits of cancer-directed surgery (CDS) by analyzing a national cohort and identifying prognostic factors that aid the selection of candidates for CDS or recruitment into experimental trials. Data for patients with PDAC and hepatic metastasis were extracted from the population-based Surveillance, Epidemiology, and End Results database (SEER). The bias between CDS and non-CDS groups was minimized with Propensity Score Matching (PSM), and the prognostic role of CDS was investigated by comparing Kaplan-Meier estimators and Cox proportional hazard models. A total of 12,018 patients were extracted from the database, including 259 patients who underwent CDS that were 1:1 propensity score-matched with patients who did not receive CDS. CDS appeared to significantly prolong median overall survival from 5 to 10 months. Multivariate analysis revealed chemotherapy as a protective prognostic, whilst survival was impaired by old age and tumors that were poorly differentiated (Grades III–IV). These factors can be used to select patients likely to benefit from CDS treatment, which may facilitate recruitment into randomized controlled trials.

Worth it or not? Primary tumor resection for stage IV pancreatic cancer patients: A SEER-based analysis of 15,836 cases

BACKGROUND

Primary tumor resection (PTR) as a treatment option for patients with stage IV pancreatic cancer (PC) is controversial.

PATIENTS AND METHODS

Stage IV PC patients, with treatment data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER), were screened. The main outcomes were overall survival (OS) and cancer-specific survival (CSS).

RESULTS

We enrolled 15,836 stage IV PC patients in this study. Propensity score-matched analyses revealed improved OS and CSS of patients receiving chemotherapy plus PTR versus chemotherapy (median survival time [MSTOS ]: 13 vs. 9 months, p = 0.024; MSTCSS : 14 vs. 10 months, p = 0.035), and chemoradiotherapy plus PTR versus chemoradiotherapy (MSTOS : 14 vs. 7 months, p = 0.044; MSTCSS : 14 vs. 7 months, p = 0.066). Multivariate adjusted analyses further confirmed these results. Stratified with different metastatic modalities, multivariate analyses suggested that PTR significantly improved the OS and CSS among patients with ≤1 metastatic organ, and that patients with brain metastasis might not benefit from chemotherapy treatment.

CONCLUSION

PTR improves the OS and CSS of stage IV PC patients on the basis of chemotherapy or chemoradiotherapy, provided that the metastases involve ≤1 organ. Chemotherapy, however, should be carefully considered in patients with metastases involving the brain.

Stereotactic body radiation therapy with sequential S-1 for patients with locally advanced pancreatic cancer and poor performance status: An open-label, single-arm, phase 2 trial

PURPOSE

The optimal treatment for a particularly neglected group of patients with locally advanced pancreatic cancer (LAPC) and poor performance status, who are usually excluded from most clinical trials, is required. Therefore, we aim to investigate the efficacy and safety of stereotactic body radiation therapy (SBRT) with sequential S-1 for those patients.

METHODS

Eligible patients had histologically and radiographically confirmed LAPC and ECOG performance status of 2 or more points determined by two independent physicians. Radiation doses ranged from 35-40 Gy/5f. S-1 was taken orally, twice daily, at a dose of 80 mg/m² for 28 days, followed by a 14-day interval, which repeated for 6 cycles and was initiated one month after SBRT. The primary endpoint was 1-year overall survival (OS). The secondary endpoints were OS, progression free survival (PFS), treatment-related toxicity and quality of life. The study was registered at ClinicalTrials.gov: NCT02704143.

RESULTS

Sixty-three patients were enrolled. At the time of data cut-off, all patients died. No patients were lost to follow-up. Median follow-up was 15.8 months (95%CI 12.9-18.7 months). One-year OS was noted in 46 of 63 patients (73.0%, 95%CI 67.4%-78.6%). The median OS and PFS was 14.4 (95%CI 13.2-15.6 months) and 10.1 months (95%CI 9.7-10.5 months) respectively. Eighteen patients (28.6%) had grade 3 toxicity. According to Quality of Life Questionnaire-Core 30, significant improvements of abdominal pain were found, and patients with poorer baseline global health status had greater improvement of health status and pain relief after treatment.

CONCLUSIONS

SBRT with sequential S-1 shows promising efficacy and acceptable toxicity in poor performance status patients with LAPC.