Recurrent disease detection after resection of pancreatic ductal adenocarcinoma using a recurrence-focused surveillance strategy (RADAR-PANC): protocol of an international randomized controlled trial according to the Trials within Cohorts design.

BACKGROUND: Disease recurrence remains one of the biggest concerns in patients after resection of pancreatic ductal adenocarcinoma (PDAC). Despite (neo)adjuvant systemic therapy, most patients experience local and/or distant PDAC recurrence within 2 years. High-level evidence regarding the benefits of recurrence-focused surveillance after PDAC resection is missing, and the impact of early detection and treatment of recurrence on survival and quality of life is unknown. In most European countries, recurrence-focused follow-up after surgery for PDAC is currently lacking. Consequently, guidelines regarding postoperative surveillance are based on expert opinion and other low-level evidence. The recent emergence of more potent local and systemic treatment options for PDAC recurrence has increased interest in early diagnosis. To determine whether early detection and treatment of recurrence can lead to improved survival and quality of life, we designed an international randomized trial. METHODS: This randomized controlled trial is nested within an existing prospective cohort in pancreatic cancer centers in the Netherlands (Dutch Pancreatic Cancer Project; PACAP) and the United Kingdom (UK) (Pancreas Cancer: Observations of Practice and survival; PACOPS) according to the "Trials within Cohorts" (TwiCs) design. All PACAP/PACOPS participants with a macroscopically radical resection (R0-R1) of histologically confirmed PDAC, who provided informed consent for TwiCs and participation in quality of life questionnaires, are included. Participants randomized to the intervention arm are offered recurrence-focused surveillance, existing of clinical evaluation, serum cancer antigen (CA) 19-9 testing, and contrast-enhanced computed tomography (CT) of chest and abdomen every three months during the first 2 years after surgery. Participants in the control arm of the study will undergo non-standardized clinical follow-up, generally consisting of clinical follow-up with imaging and serum tumor marker testing only in case of onset of symptoms, according to local practice in the participating hospital. The primary endpoint is overall survival. Secondary endpoints include quality of life, patterns of recurrence, compliance to and costs of recurrence-focused follow-up, and the impact on recurrence-focused treatment. DISCUSSION: The RADAR-PANC trial will be the first randomized controlled trial to generate high level evidence for the current clinical equipoise regarding the value of recurrence-focused postoperative surveillance with serial tumor marker testing and routine imaging in patients after PDAC resection. The Trials within Cohort design allows us to study the acceptability of recurrence-focused surveillance among cohort participants and increases the generalizability of findings to the general population. While it is strongly encouraged to offer all trial participants treatment at time of recurrence diagnosis, type and timing of treatment will be determined through shared decision-making. This might reduce the potential survival benefits of recurrence-focused surveillance, although insights into the impact on patients' quality of life will be obtained. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04875325 . Registered on May 6, 2021.

Prediction of Isolated Local Recurrence After Resection of Pancreatic Ductal Adenocarcinoma: A Nationwide Study.

BACKGROUND: Distinguishing postoperative fibrosis from isolated local recurrence (ILR) after resection of pancreatic ductal adenocarcinoma (PDAC) is challenging. A prognostic model that helps to identify patients at risk of ILR can assist clinicians when evaluating patients' postoperative imaging. This nationwide study aimed to develop a clinically applicable prognostic model for ILR after PDAC resection. PATIENTS AND METHODS: An observational cohort study was performed, including all patients who underwent PDAC resection in the Netherlands (2014-2019; NCT04605237). On the basis of recurrence location (ILR, systemic, or both), multivariable cause-specific Cox-proportional hazard analysis was conducted to identify predictors for ILR and presented as hazard ratios (HRs) with 95% confidence intervals (CIs). A predictive model was developed using Akaike's Information Criterion, and bootstrapped discrimination and calibration indices were assessed. RESULTS: Among 1194/1693 patients (71%) with recurrence, 252 patients (21%) developed ILR. Independent predictors for ILR were resectability status (borderline versus resectable, HR 1.42; 95% CI 1.03-1.96; P = 0.03, and locally advanced versus resectable, HR 1.11; 95% CI 0.68-1.82; P = 0.66), tumor location (head versus body/tail, HR 1.50; 95% CI 1.00-2.25; P = 0.05), vascular resection (HR 1.86; 95% CI 1.41-2.45; P < 0.001), perineural invasion (HR 1.47; 95% CI 1.01-2.13; P = 0.02), number of positive lymph nodes (HR 1.04; 95% CI 1.01-1.08; P = 0.02), and resection margin status (R1 < 1 mm versus R0 ≥ 1 mm, HR 1.64; 95% CI 1.25-2.14; P < 0.001). Moderate performance (concordance index 0.66) with adequate calibration (slope 0.99) was achieved. CONCLUSIONS: This nationwide study identified factors predictive of ILR after PDAC resection. Our prognostic model, available through www.pancreascalculator.com , can be utilized to identify patients with a higher a priori risk of developing ILR, providing important information in patient evaluation and prognostication.

A nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy (ARCADE).

BACKGROUND: Disease recurrence is the main cause of mortality after resection of pancreatic ductal adenocarcinoma (PDAC). In 20-30% of resected patients, isolated local PDAC recurrence occurs. Retrospective studies have suggested that stereotactic body radiation therapy (SBRT) might lead to improved local control in these patients, potentially having a beneficial effect on both survival and quality of life. The "nationwide randomized controlled trial on additional treatment for isolated local pancreatic cancer recurrence using stereotactic body radiation therapy" (ARCADE) will investigate the value of SBRT in addition to standard of care in patients with isolated local PDAC recurrence compared to standard of care alone, regarding both survival and quality of life outcomes. METHODS: The ARCADE trial is nested within a prospective cohort (Dutch Pancreatic Cancer Project; PACAP) according to the 'Trials within Cohorts' design. All PACAP participants with isolated local PDAC recurrence after primary resection who provided informed consent for being randomized in future studies are eligible. Patients will be randomized for local therapy (5 fractions of 8 Gy SBRT) in addition to standard of care or standard of care alone. In total, 174 patients will be included. The main study endpoint is survival after recurrence. The most important secondary endpoint is quality of life. DISCUSSION: It is hypothesized that additional SBRT, compared to standard of care alone, improves survival and quality of life in patients with isolated local recurrence after PDAC resection. TRIAL REGISTRATION: ClinicalTrials.gov registration NCT04881487 . Registered on May 11, 2021.

The treatment and survival of elderly patients with locally advanced pancreatic cancer: A post-hoc analysis of a multicenter registry.

BACKGROUND: The treatment options for patients with locally advanced pancreatic cancer (LAPC) have improved in recent years and consequently survival has increased. It is unknown, however, if elderly patients benefit from these improvements in therapy. With the ongoing aging of the patient population and an increasing incidence of pancreatic cancer, this patient group becomes more relevant. This study aims to clarify the association between increasing age, treatment and overall survival in patients with LAPC. METHODS: Post-hoc analysis of a multicenter registry including consecutive patients with LAPC, who were registered in 14 centers of the Dutch Pancreatic Cancer Group (April 2015-December 2017). Patients were divided in three groups according to age (<65, 65-74 and ≥75 years). Primary outcome was overall survival stratified by primary treatment strategy. Multivariable regression analyses were performed to adjust for possible confounders. RESULTS: Overall, 422 patients with LAPC were included; 162 patients (38%) aged <65 years, 182 patients (43%) aged 65-74 and 78 patients (19%) aged ≥75 years. Chemotherapy was administered in 86%, 81% and 50% of the patients in the different age groups (p<0.01). Median overall survival was 12, 11 and 7 months for the different age groups (p<0.01).Patients treated with chemotherapy showed comparable median overall survival of 13, 14 and 10 months for the different age groups (p=0.11). When adjusted for confounders, age was not associated with overall survival. CONCLUSION: Elderly patients are less likely to be treated with chemotherapy, but when treated with chemotherapy, their survival is comparable to younger patients.

The time to progression ratio: a new individualized volumetric parameter for the early detection of clinical benefit of targeted therapies.

BACKGROUND: Early signs of efficacy are critical in drug development. Response Evaluation Criteria in Solid Tumors (RECIST) are commonly used to determine the efficacy of anti-cancer therapy in clinical trials. RECIST, however, emphasizes the value of tumor shrinkage, while many targeted agents induce prolonged tumor growth arrest. This limits its use for the detection of treatment efficacy for these more cytostatic regimens. Therefore, we designed an individualized variant of a time to progression (TTP) end point based on prospective volumetric measurements and an intra-patient control, the TTP ratio. PATIENTS AND METHODS: Patients with any metastatic malignancy, without regular treatment options, were treated with the mTOR inhibitor everolimus. Treatment response was determined using both RECIST and the TTP ratio. The TTP ratio was defined as the volumetric pretreatment TTP divided by the volumetric on-treatment TTP. A patient was classified as a responder if the TTP ratio was <0.7. Consistency and reproducibility of volumetric measurements were determined. RESULTS: Seventy-three patients were included of whom 59 started treatment. A TTP ratio could be established in 73% (n = 43) of the treated patients. The inter-observer agreement for volumetric progression was 0.78 (95% confidence interval 0.70-0.87) (Krippendorff's α-coefficient). According to RECIST, 35 patients (59%) had stable disease (SD) and 1 patient demonstrated a partial response (PR), whereas only 21 patients (36%) met the prespecified criteria for treatment efficacy according to the TTP ratio. Treatment response according to both the TTP ratio and RECIST (SD + PR) correlated with overall survival (OS) [P(log-rank) < 0.001]. The TTP ratio, however, was also able to differentiate which patients had a better OS within the RECIST SD group [P(log-rank) = 0.0496]. CONCLUSION: The TTP ratio had a high inter-observer agreement, correlated with OS and identified which patients within the RECIST SD group had a longer OS. CLINICALTRIALSGOV IDENTIFIER: NCT01566279.

Pharmacokinetically guided sunitinib dosing: a feasibility study in patients with advanced solid tumours.

BACKGROUND: Plasma exposure of sunitinib shows large inter-individual variation. Therefore, a pharmacokinetic (PK) study was performed to determine safety and feasibility of sunitinib dosing based on PK levels. METHODS: Patients were treated with sunitinib 37.5 mg once daily. At days 15 and 29 of treatment, plasma trough levels of sunitinib and N-desethyl sunitinib were measured. If the total trough level (TTL) was <50 ng ml(-1) and the patient did not show any grade ⩾3 toxicity, the daily sunitinib dose was increased by 12.5 mg. If the patient suffered from grade ⩾3 toxicity, the sunitinib dose was lowered by 12.5 mg. RESULTS: Twenty-nine out of 43 patients were evaluable for PK assessments. Grade ⩾3 adverse events were experienced in seven patients (24%) at the starting dose and in nine patients (31%) after dose escalation. TTLs were below target in 15 patients (52%) at the starting dose. Of these, five patients (17%) reached target TTL after dose escalation without additional toxicity. CONCLUSIONS: In a third of the patients that were below target TTL at standard dose, the sunitinib dose could be increased without additional toxicities. This could be the basis for future studies and the implementation of a PK-guided dosing strategy in clinical practice.

Treatment-induced host-mediated mechanisms reducing the efficacy of antitumor therapies.

In addition to its direct effects on tumor cells, chemotherapy can rapidly activate various host processes that contribute to therapy resistance and tumor regrowth. The host response to chemotherapy consists of changes in numerous cell types and cytokines. Examples include the acute mobilization and tumor homing of pro-angiogenic bone marrow-derived cells, activation of cells in the tumor microenvironment to produce systemic or paracrine factors, and tissue-specific responses that provide a protective niche for tumor cells. All of these factors reduce chemotherapy efficacy, and blocking the host response at various levels may therefore significantly improve treatment outcome. However, before the combination of conventional chemotherapy with agents blocking specific aspects of the host response can be implemented into clinical practice, a better understanding of the molecular mechanisms behind the host response is required.

Quantification of cabazitaxel, its metabolite docetaxel and the determination of the demethylated metabolites RPR112698 and RPR123142 as docetaxel equivalents in human plasma by liquid chromatography-tandem mass spectrometry.

We present a sensitive validated LC-MS/MS assay for the simultaneous determination of cabazitaxel and docetaxel in human plasma, with calibration ranges of 1.0-150 ng/mL for cabazitaxel and 0.1-15 ng/mL for docetaxel. Sample pretreatment consisted of liquid-liquid extraction with tert-butyl methyl ether. Chromatographic separation was achieved on a Zorbax Extend C18 column using a gradient mixture of 10mM ammonium hydroxide and methanol. Mass detection was carried out by turbo ion spray ionization in positive ion multiple reaction monitoring mode. All inter-day accuracies and precisions were within ±15% of the nominal value and within ±20% at the lower limit of quantitation. Demethylations of cabazitaxel yielding the metabolites RPR112698 and RPR123142 were monitored semi-quantitatively and quantified as ng docetaxel equivalents. Plasma samples of a prostate cancer patient treated with cabazitaxel were analyzed to demonstrate the usefulness of the presented assay for clinical drug monitoring. In conclusion, this method can be applied to support clinical pharmacokinetic studies with the novel anticancer drug cabazitaxel.

[A nationwide Dutch study into the optimal treatment of patients with infected necrotising pancreatitis: the PANTER trial]. / Landelijk onderzoek naar optimale behandeling van patiënten met geïnfecteerde necrotiserende pancreatitis: PANTER-trial.

Surgical intervention in infected necrotising pancreatitis generally consists of necrosectomy via laparotomy. The morbidity and mortality after this procedure might be reduced by minimally invasive strategies. The 20 hospitals of the Dutch Acute Pancreatitis Study Group are currently enrolling patients in a randomised trial to compare (a) laparotomy with necrosectomy and continuous postoperative lavage with (b) CT-guided or endoscopic transgastric drainage, if necessary, followed by videoscopic assisted retroperitoneal debridement (VARD): the PANTER trial ('pancreatitis, necrosectomy versus a minimally invasive step-up approach'). The primary endpoint is the proportion of patients suffering from major postoperative morbidity and mortality. Patients with (suspected) infected necrotising pancreatitis can be put forward for participation in the trial in one of the 20 participating centres.