Enhanced antitumour immunity following neoadjuvant chemoradiotherapy mediates a favourable prognosis in women with resected pancreatic cancer.

BACKGROUND: This study investigates sex disparities in clinical outcomes and tumour immune profiles in patients with pancreatic ductal adenocarcinoma (PDAC) who underwent upfront resection or resection preceded by gemcitabine-based neoadjuvant chemoradiotherapy (nCRT). METHODS: Patients originated from the PREOPANC randomised controlled trial. Upfront surgery was performed in 82 patients, and 66 received nCRT before resection. The impact of sex on overall survival (OS) was investigated using Cox proportional hazards models. The immunological landscape within the tumour microenvironment (TME) was mapped using transcriptomic and spatial proteomic profiling. RESULTS: The 5-year OS rate differed between the sexes following resection preceded by nCRT, with 43% for women compared with 22% for men. In multivariate analysis, the female sex was a favourable independent prognostic factor for OS only in the nCRT group (HR 0.19; 95% CI 0.07 to 0.52). Multivariate heterogeneous treatment effects analysis revealed a significant interaction between sex and treatment, implying increased nCRT efficacy among women with resected PDAC. The TME of women contained fewer protumoural CD163+MRC1+M2 macrophages than that of men after nCRT, as indicated by transcriptomic and validated using spatial proteomic profiling. CONCLUSION: PDAC tumours of women are more sensitive to gemcitabine-based nCRT, resulting in longer OS after resection compared with men. This may be due to enhanced immunity impeding the infiltration of protumoral M2 macrophages into the TME. Our findings highlight the importance of considering sex disparities and mitigating immunosuppressive macrophage polarisation for personalised PDAC treatment.

Predictive value of baseline serum carbohydrate antigen 19-9 level on treatment effect of neoadjuvant chemoradiotherapy in patients with resectable and borderline resectable pancreatic cancer in two randomized trials.

BACKGROUND: Guidelines suggest that the serum carbohydrate antigen (CA19-9) level should be used when deciding on neoadjuvant treatment in patients with resectable and borderline resectable pancreatic ductal adenocarcinoma (hereafter referred to as pancreatic cancer). In patients with resectable pancreatic cancer, neoadjuvant therapy is advised when the CA19-9 level is 'markedly elevated'. This study investigated the impact of baseline CA19-9 concentration on the treatment effect of neoadjuvant chemoradiotherapy (CRT) in patients with resectable and borderline resectable pancreatic cancers. METHODS: In this post hoc analysis, data were obtained from two RCTs that compared neoadjuvant CRT with upfront surgery in patients with resectable and borderline resectable pancreatic cancers. The effect of neoadjuvant treatment on overall survival was compared between patients with a serum CA19-9 level above or below 500 units/ml using the interaction test. RESULTS: Of 296 patients, 179 were eligible for analysis, 90 in the neoadjuvant CRT group and 89 in the upfront surgery group. Neoadjuvant CRT was associated with superior overall survival (HR 0.67, 95 per cent c.i. 0.48 to 0.94; P = 0.019). Among 127 patients (70, 9 per cent) with a low CA19-9 level, median overall survival was 23.5 months with neoadjuvant CRT and 16.3 months with upfront surgery (HR 0.63, 0.42 to 0.93). For 52 patients (29 per cent) with a high CA19-9 level, median overall survival was 15.5 months with neoadjuvant CRT and 12.9 months with upfront surgery (HR 0.82, 0.45 to 1.49). The interaction test for CA19-9 level exceeding 500 units/ml on the treatment effect of neoadjuvant CRT was not significant (P = 0.501). CONCLUSION: Baseline serum CA19-9 level defined as either high or low has prognostic value, but was not associated with the treatment effect of neoadjuvant CRT in patients with resectable and borderline resectable pancreatic cancers, in contrast with current guideline advice.

Diagnostic performance of endoscopic tissue acquisition for pancreatic ductal adenocarcinoma in the PREOPANC and PREOPANC-2 trials.

BACKGROUND: Neoadjuvant treatment for pancreatic ductal adenocarcinoma (PDAC) has increased, necessitating histopathologic confirmation of cancer. This study evaluates the performance of endoscopic tissue acquisition (TA) procedures for borderline resectable and resectable PDAC. METHODS: Pathology reports of patients included in two nationwide randomized controlled trials (PREOPANC and PREOPANC-2) were reviewed. The primary outcome was sensitivity for malignancy (SFM), considering both "suspicious for" and "malignant" as positive. Secondary outcomes were rate of adequate sampling (RAS) and diagnoses other than PDAC. RESULTS: Overall, 892 endoscopic procedures were performed in 617 patients, including endoscopic ultrasonography (EUS)-guided TA in 550 (89.1%), endoscopic retrograde cholangiopancreatography (ERCP)-guided brush cytology in 188 (30.5%), and periampullary biopsies in 61 patients (9.9%). The SFM was 85.2% for EUS, 88.2% for repeat EUS, 52.7% for ERCP, and 37.7% for periampullary biopsies. The RAS ranged 94-100%. Diagnoses other than PDAC were other periampullary cancers in 24 (5.4%), premalignant disease in five (1.1%), and pancreatitis in three patients (0.7%). CONCLUSIONS: EUS-guided TA of patients with borderline resectable and resectable PDAC included in RCTs had an SFM above 85% for both first and repeat procedures, meeting international standards. Two percent had false positive result for malignancy and 5% had other (non-PDAC) periampullary cancers.

External Validity of the Multicenter Randomized PREOPANC Trial on Neoadjuvant Chemoradiotherapy in Pancreatic Cancer: Outcome of Eligible but Nonrandomized Patients.

OBJECTIVES: To investigate the accrual proportion and patients' reasons for not participating in the PREOPANC trial on neoadjuvant chemoradiotherapy versus immediate surgery in resectable and borderline resectable pancreatic cancer, and to compare these patients' outcomes with those of patients who had been randomized in the trial. SUMMARY OF BACKGROUND DATA: The external validity of multicenter randomized trials in cancer treatment has been criticized for suboptimal non-representative inclusion. In trials, it is unclear how outcomes compare between randomized and nonrandomized patients. METHODS: At 8 of 16 participant centers, this multicenter observational study identified validation patients, who had been eligible but not randomized during recruitment for the PREOPANC trial. We assessed the accrual proportion, investigated their most common reasons for not participating in the trial, and compared resection rates, radical (R0) resection rates, and overall survival between the validation patients and PREOPANC patients, who had been randomized in the trial to immediate surgery. RESULTS: In total, 455 patients had been eligible during the recruitment period, 151 of whom (33%) had been randomized. Fifty-five percent of the 304 validation patients had refused to participate. Median overall survival in the validation group was 15.2 months, against 15.5 months in the PREOPANC group (P = 1.00). The respective resection rates (76% vs 73%) and R0 resection rates (51% vs 46%) did not differ between the groups. CONCLUSIONS: The PREOPANC trial included a reasonable percentage of 33% of eligible patients. In terms of the outcomes survival, resection rate, and R0 resection rate, this appeared to be a representative group.

Surgical Complications in a Multicenter Randomized Trial Comparing Preoperative Chemoradiotherapy and Immediate Surgery in Patients With Resectable and Borderline Resectable Pancreatic Cancer (PREOPANC Trial).

OBJECTIVES: To investigate the effect of preoperative chemoradiotherapy on surgical complications in patients after pancreatic resection for (borderline-)resectable pancreatic cancer. SUMMARY OF BACKGROUND DATA: Preoperative chemoradiotherapy is increasingly used in patients with (borderline-)resectable pancreatic cancer. concerns have been raised about the potential harmful effect of any preoperative therapy on the surgical complication rate after pancreatic resection. METHODS: An observational analysis was performed within the multicenter randomized controlled PREOPANC trial (April 2013-July 2017). The trial randomly assigned (1:1) patients to preoperative chemoradiotherapy followed by surgery and the remaining adjuvant chemotherapy or to immediate surgery, followed by adjuvant chemotherapy. The main analysis consisted of a per-protocol approach. The endpoints of the present analyses were the rate of postoperative complications. RESULTS: This study included 246 patients from 16 centers, of whom 66 patients underwent resection after preoperative therapy and 98 patients after immediate surgery. No differences were found regarding major complications (37.9% vs 30.6%, P=0.400), postpancreatectomy hemorrhage (9.1% vs 5.1%, P=0.352), delayed gastric emptying (21.2% vs 22.4%, P=0.930), bile leakage (4.5% vs 3.1%, P=0.686), intra-abdominal infections (12.1% vs 10.2%, P=0.800), and mortality (3.0% vs 4.1%, P=1.000). There was a significant lower incidence of postoperative pancreatic fistula in patients who received preoperative chemoradiotherapy (0% vs 9.2%, P=0.011). CONCLUSIONS: Preoperative chemoradiotherapy did not increase the incidence of surgical complications or mortality and reduced the rate of postoperative pancreatic fistula after resection in patients with (borderline-)resectable pancreatic cancer.

High-grade mesenchymal pancreatic ductal adenocarcinoma drives stromal deactivation through CSF-1.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an abundance of stroma. Multiple molecular classification efforts have identified a mesenchymal tumor subtype that is consistently characterized by high-grade growth and poor clinical outcome. The relation between PDAC stroma and tumor subtypes is still unclear. Here, we aimed to identify how PDAC cells instruct the main cellular component of stroma, the pancreatic stellate cells (PSCs). We found in primary tissue that high-grade PDAC had reduced collagen deposition compared to low-grade PDAC. Xenografts and organotypic co-cultures established from mesenchymal-like PDAC cells featured reduced collagen and activated PSC content. Medium transfer experiments using a large set of PDAC cell lines revealed that mesenchymal-like PDAC cells consistently downregulated ACTA2 and COL1A1 expression in PSCs and reduced proliferation. We identified colony-stimulating factor 1 as the mesenchymal PDAC-derived ligand that deactivates PSCs, and inhibition of its receptor CSF1R was able to counteract this effect. In conclusion, high-grade PDAC features stroma that is low in collagen and activated PSC content, and targeting CSF1R offers direct options to maintain a tumor-restricting microenvironment.

A randomized phase-II study of reirradiation and hyperthermia versus reirradiation and hyperthermia plus chemotherapy for locally recurrent breast cancer in previously irradiated area.

BACKGROUND: In patients with inoperable local regional recurrences of breast cancer in previously irradiated areas, local control is difficult to maintain and treatment options are limited. The Dutch standard treatment for such recurrences is reirradiation combined with hyperthermia. Apart from enhancing the effect of reirradiation, hyperthermia is also known to improve local effects of chemotherapy like cisplatin. This randomized phase-II trial compares reirradiation and hyperthermia versus the same treatment combined with cisplatin. PATIENTS AND METHODS: From December 2010 up to January 2019, 49 patients were randomized, 27 in the standard arm and 22 in the combined arm. A total of 32 Gy was given in eight fractions of 4 Gy in 4 weeks, at two fractions per week. After January 2015, the radiation schedule was changed to 46 Gy in 23 fractions of 2 Gy, at five fractions per week. Hyperthermia was added once a week after radiotherapy. The combined arm was treated with four cycles of weekly cisplatin 40 mg/m2. RESULTS: Complete response rate was 60.9% in the standard arm and 61.1% in the combined arm (p = 0.87). Partial response rate was 30.4% in the standard arm and 33.3% in the combined arm (p = 0.79). One-year overall survival was 63.4% in the standard arm and 57.4% in the combined arm. One-year local progression-free interval was 81.5% in the standard arm and 88.1% in the combined arm (p = 0.95). Twenty-five percentage of patients in the standard arm experienced grade 3 or 4 acute toxicity and 29% of patients in the combined arm (p = 0.79). CONCLUSION: No potential benefit could be detected of adding cisplatin to reirradiation and hyperthermia in patients with recurrent breast cancer in a previously irradiated area. With or without cisplatin, most patients had subsequent local control until last follow-up or death.

Comparison of the clinical performance of a hybrid Alba 4D and the AMC-4 locoregional hyperthermia systems.

OBJECTIVE: The in-house developed 70 MHz AMC-4 locoregional hyperthermia system has been in clinical use since 1984. This device was recently commercialized as the Alba 4D (Medlogix®, Rome, Italy), with a similar geometrical 4-waveguide design. At the time of this study a hybrid Alba 4D was installed at our center, which incorporated elements of the AMC-4. This study aims to compare clinical performance of both devices. METHODS: During one year after clinical acceptance of the hybrid Alba 4D, both devices were used for treatment delivery in patients scheduled for locoregional hyperthermia. Each patient started with the AMC-4, next sessions were allocated to either device. Possible differences between Alba 4D and AMC-4 sessions in power, achieved temperature T0, T10, T50, T90, T100, treatment time and complaints per session, were evaluated using linear mixed models (LMMs) for repeated measures with patient as random effect. RESULTS: From March 2018 to April 2019, eleven patients with cervical, pancreatic, vaginal carcinoma and uterine leiomyosarcoma received 27 locoregional hyperthermia sessions with the Alba 4D and 34 sessions with the AMC-4. Median number of sessions per patient was 5 (range 3-13). Treatment results for both devices were not significantly different: T50 was 40.5 ± 1.0 °C vs. 40.8 ± 0.7 °C, applied power was 500 ± 79 W vs. 526 ± 108 W, for the Alba 4D vs. AMC-4, respectively. CONCLUSION: Results of the first patients treated with the hybrid Alba 4D demonstrated comparable clinical performance of the Alba 4D and AMC-4 locoregional hyperthermia systems, and both devices are expected to yield similar favorable clinical results.

Amsterdam International Consensus Meeting: tumor response scoring in the pathology assessment of resected pancreatic cancer after neoadjuvant therapy.

Histopathologically scoring the response of pancreatic ductal adenocarcinoma (PDAC) to neoadjuvant treatment can guide the selection of adjuvant therapy and improve prognostic stratification. However, several tumor response scoring (TRS) systems exist, and consensus is lacking as to which system represents best practice. An international consensus meeting on TRS took place in November 2019 in Amsterdam, The Netherlands. Here, we provide an overview of the outcomes and consensus statements that originated from this meeting. Consensus (≥80% agreement) was reached on a total of seven statements: (1) TRS is important because it provides information about the effect of neoadjuvant treatment that is not provided by other histopathology-based descriptors. (2) TRS for resected PDAC following neoadjuvant therapy should assess residual (viable) tumor burden instead of tumor regression. (3) The CAP scoring system is considered the most adequate scoring system to date because it is based on the presence and amount of residual cancer cells instead of tumor regression. (4) The defining criteria of the categories in the CAP scoring system should be improved by replacing subjective terms including "minimal" or "extensive" with objective criteria to evaluate the extent of viable tumor. (5) The improved, consensus-based system should be validated retrospectively and prospectively. (6) Prospective studies should determine the extent of tissue sampling that is required to ensure adequate assessment of the residual cancer burden, taking into account the heterogeneity of tumor response. (7) In future scientific publications, the extent of tissue sampling should be described in detail in the "Materials and methods" section.

Added Value of Radiotherapy Following Neoadjuvant FOLFIRINOX for Resectable and Borderline Resectable Pancreatic Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: The added value of radiotherapy following neoadjuvant FOLFIRINOX chemotherapy in patients with resectable or borderline resectable pancreatic cancer ((B)RPC) is unclear. The objective of this meta-analysis was to compare outcomes of patients who received neoadjuvant FOLFIRINOX alone or combined with radiotherapy. METHODS: A systematic literature search was performed in Embase, Medline (ovidSP), Web of Science, Scopus, Cochrane, and Google Scholar. The primary endpoint was pooled median overall survival (OS). Secondary endpoints included resection rate, R0 resection rate, and other pathologic outcomes. RESULTS: We included 512 patients with (B)RPC from 15 studies, of which 7 were prospective nonrandomized studies. In total, 351 patients (68.6%) were treated with FOLFIRINOX alone (8 studies) and 161 patients (31.4%) were treated with FOLFIRINOX and radiotherapy (7 studies). The pooled estimated median OS was 21.6 months (range 18.4-34.0 months) for FOLFIRINOX alone and 22.4 months (range 11.0-37.7 months) for FOLFIRINOX with radiotherapy. The pooled resection rate was similar (71.9% vs. 63.1%, p = 0.43) and the pooled R0 resection rate was higher for FOLFIRINOX with radiotherapy (88.0% vs. 97.6%, p = 0.045). Other pathological outcomes (ypN0, pathologic complete response, perineural invasion) were comparable. CONCLUSIONS: In this meta-analysis, radiotherapy following neoadjuvant FOLFIRINOX was associated with an improved R0 resection rate as compared with neoadjuvant FOLFIRINOX alone, but a difference in survival could not be demonstrated. Randomized trials are needed to determine the added value of radiotherapy following neoadjuvant FOLFIRINOX in patients with (B)PRC.