Communication, understanding and engagement of patients with pancreatic cancer at time of diagnosis

BACKGROUND

Objectives: To investigate communication clarity and understanding at the time of pancreatic adenocarcinoma (PDAC) diagnosis and whether they can influence patient engagement and compliance.

METHODS

Consecutive PDAC patients were enrolled at the time of diagnosis after obtaining informed consent in a single-center study. The patients completed a validated scale (PHE-s®), and the understanding rate was assessed using standardized tools. Patient compliance was evaluated, and the correlation between the PHE-s®, understanding, and compliance was calculated.

RESULTS

Thirty patients were enrolled (15 female) with a mean age 64.4, 13 were metastatic. The mean visit time was 31 min, being longer if visiting doctor was an oncologist (p = 0.002). The engagement level was high in 70% of the patients, and all but one were compliant. The analysis of doctor-patient interactions showed a median of 121 conversational turns for doctors, 75 for patients, and 20 for caregivers (p < 0.0001), and the median percentage of speaking time was 77% for doctors, 13% for patients, and 2% for caregivers (p < 0.0001). Female caregivers spent more time speaking than did male caregivers (median 11.6% vs. 1.3%; p = 0.06). There were 290 instances of problematic understanding, most of which occurred during the taking of patients' personal medical history for doctors, while for patients and caregivers, these occurred mainly during the discussion of diagnosis/treatment (p < 0.0001). In a multivariable analysis, only origin from central or southern Italy was associated with high engagement (p = 0.0087).

CONCLUSION

In this first attempt to measure clarity of communication and engagement in patients with PDAC, typical features of conversation and problematic understanding emerged, which deserves further investigation.

Cyclophosphamide maintenance to extend combination chemotherapy-free interval in metastatic pancreatic ductal adenocarcinoma

BACKGROUND

Administering chemotherapy until progression to metastatic pancreatic ductal adenocarcinoma (PDAC) patients lacks of supporting evidence and causes cumulative toxicity. We explored the role of cyclophosphamide as maintenance therapy.

METHODS

PDAC germline BRCA1-2 wild-type patients who were progression-free after ≥6 months of any regimen and line of chemotherapy and received maintenance cyclophosphamide (mCTX) (50 mg/day), were included in the analysis.

RESULTS

42 patients were included in the analysis. Thirty-nine patients had progression of disease. Median PFS was 3.5 (range 1.0-31+) months. PFS rates at 6 and 12 months were 26.2% and 11.9%. At a median follow-up of 20.0 months (range 12.1-31.0 months), 20 patients died and 22 are alive. Median OS was 20.0 months (range 2.2-31.0+). OS at 6 and 12 months was 97.6% (95%CI: 93.4-100), and 73.8% (95% CI: 61.1-86.5), respectively. Only 2 patients receiving mCTX had Grade 3 toxicity.

CONCLUSIONS

mCTX therapy yielded promising PFS and OS outcome in PDAC patients who were progression-free after induction chemotherapy, with unremarkable toxicity. Accordingly, this approach warrants further investigation.

Exploring the optimal therapeutic management of stage ypIA pancreatic ductal adenocarcinoma patients in the era of primary chemotherapy

BACKGROUND

Data on the proper post-surgical chemotherapy (PSC) in pancreatic ductal adenocarcinoma (PDAC) patients already treated with neoadjuvant therapy (NAT) are lacking, especially for stage ypIA.

AIM AND METHODS

We retrospectively analyzed ypT1N0M0 (ypIA) PDAC patients resected after NAT between 2015 and 2020 at our Institution. Primary endpoint was median disease free-survival (DFS) according to PSC treatment.

RESULTS

Seventy-five out of 363 patients achieved a pathological ypIA after NAT (20.6%) and 72 were analyzed. Among the study population 34 patients (47%) were treated with NAT ≤4 months and 38 (53%) >4 months. After surgery, 10 patients (14%) received PSC using the same multidrug NAT regimen (Group A); 35 (49%) received PSC with a different regimen (Group B), with either single agents in 24 patients (68.5%) or combination schedules in 11 (31.5%); 27 patients (14%) did not receive any PSC (Group C). DFS was longer in group A and C as opposed to group B (p = 0.006).

CONCLUSION

Patients affected by ypIA PDAC treated with a proper multi-agent chemotherapy for more than 4 months show an improved DFS, regardless of the peri‑operative or totally pre-surgical administration of treatment.

Clinical outcomes and response to chemotherapy in a cohort of pancreatic cancer patients with germline variants of unknown significance (VUS) in BRCA1 and BRCA2 genes

PURPOSE

The clinical outcome and the efficacy of chemotherapy in pancreatic cancer patients with BRCA1/2 Variants of Unknown Significance (VUS) is unknown. We explored the effects of chemotherapy with or without Platinum in non metastatic and metastatic pancreatic cancer patients with BRCA1/2 VUS.

METHODS

A retrospective analysis of non-metastatic or metastatic pancreatic cancer patients with gBRCA1/2 VUS treated in 13 Italian centers between November 2015 and December 2020 was performed. All patients were assessed for toxicity and RECIST 1.1 response. Metastatic patients were evaluated for survival outcome.

RESULTS

30 pancreatic cancer patients with gBRCA1/2 VUS were considered: 20 were M+ and 10 were non-M+. Pl-CT was recommended to 16 patients: 10 M+ (6 FOLFIRINOX and 4 PAXG) and 6 non-M+ (3 FOLFIRINOX and 3 PAXG); 11 patients received Nabpaclitaxel-Gemcitabine (AG; 8 M+) and 3 patients (2 M+) were treated with Gemcitabine (G). The RECIST 1.1 response rate was 27% for AG and 44% for Pl-CT (22% for (m) FOLFIRINOX and 71% PAXG). 1 year Progression-Free Survival was 37.5% for patients treated with AG and 33% in the Pl-CT subgroup. Median Overall Survival (OS) was 23.5 months for patients treated with AG and 14 months for the Pl-CT subgroup. 1 Year and 2 Year OS were numerically better for AG (1 Year OS: 75% vs 60% and 2 Year OS: 50% and 20% in AG and Pl-CT subgroups, respectively) as well.

CONCLUSIONS

Pl-CT does not seem to be associated with a better outcome compared to AG chemotherapy in PDAC patients with BRCA 1/2 VUS.

The role of biliary events in treatment and survival of patients with advanced pancreatic ductal adenocarcinoma

BACKGROUND

Systemic chemotherapy (CT) is the treatment of choice for advanced pancreatic ductal adenocarcinoma (PDAC). Biliary obstruction is common in this setting and may interfere with CT administration due to jaundice or cholangitis related to biliary stent malfunction.

AIMS

To evaluate the impact of biliary events on CT administration and survival in patients with stage III-IV PDAC.

METHODS

Patients enrolled in a randomized trial of nab-paclitaxel plus gemcitabine with/without capecitabine and cisplatin in advanced PDAC were included. Data on management of jaundice, biliary stents/complications and CT were prospectively collected and retrospectively analyzed. Modified overall (mOS) and progression-free (mPFS) survival were evaluated.

RESULTS

Eighty-eight patients met the inclusion criteria (50% females; median age 65years). Seven of eight (87.5%) patients who placed plastic stents developed biliary complications versus 14/30 (46.7%) with metallic stents (p = 0.071). Patients without biliary complications completed planned CT in 64.2% versus 47.6% of cases (p = 0.207). CT completion was related to longer mOS (17 vs 12 months, p = 0.005) and mPFS (9 vs 6 months, p = 0.011). mOS was shorter when biliary complications occurred (12 vs 17 months, p = 0.937), as was mPFS (6 vs 8 months, p = 0.438).

CONCLUSION

Complications related to biliary obstruction influence chemotherapy completion and survival in patients with advanced PDAC.

Predictive factors of selective transarterial embolization failure in acute renal bleeding: a single-center experience

PURPOSE

Transarterial embolization of renal artery branches (RTE) is a minimally invasive procedure commonly performed in life-threatening renal bleeding of different etiologies. Despite the widespread use of RTE, no consensus guidelines are currently available. Our aim was to investigate clinical and technical efficacy and to identify potential predictors for clinical failure of this procedure.

METHODS

All the RTE procedures performed in our Interventional Radiology unit in last 10 years were retrospectively collected and analyzed. All selected patients underwent both pre-procedural computed tomography angiography (CTA) and post-procedural CTA within 30 days. Clinical success was considered as primary endpoint. Demographic, laboratory, and diagnostic findings predictive of clinical failure of RTE were identified.

RESULTS

Over a total of 51 patients enrolled, 27 (53%) were females and 33 (64.7%) had a renal bleeding of iatrogenic origin. Technical and clinical success was 100% and 80.4%, respectively. Hematoma volumes > 258.5 cm3 measured at CTA, higher pre- and post-procedural serum creatinine (Scr) levels, an increase in Scr value > 0.135 mg/dl after the procedure, a worse post-procedural estimated glomerular filtration rate (eGFR), a post-procedural reduction of eGFR < 3.350 ml/min, and a post-procedural reduction of platelet count (PLT) > 46.50 × 103/mmc showed a significantly higher rate of clinical failure.

CONCLUSION

RTE is a safe and effective procedure in the management of acute renal bleeding of various origins. Hematoma volume, Scr, PLT, and eGFR values were found to be predictive factors of poor clinical outcome and should be closely monitored.

Routine Molecular Profiling in Both Resectable and Unresectable Pancreatic Adenocarcinoma: Relevance of Cytologic Samples

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease, for which it is crucial to promptly detect actionable and prognostic alterations to drive specific therapeutic decisions, regardless of tumor resectability status. Endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) is of key importance for PDAC diagnosis and can contribute significantly to tumor molecular profiling.

METHODS

Comprehensive genomic profile by targeted next-generation sequencing (NGS) was performed on 2 independent PDAC patient cohorts. Cohort 1 consisted of 77 patients with resectable PDAC for whom the histologic sample at the time of resection was available; for 56 patients cytologic specimens at the time of diagnosis also were obtained by EUS-FNA. Cohort 2 consisted of 20 patients with unresectable PDAC, for whom only the EUS-FNA cytologic sample was available.

RESULTS

In cohort 1, a complete concordant mutational profile between the cytologic sample at diagnosis and the corresponding histologic specimen after surgery was observed in 88% of the cases, proving the ability to detect potential clinically relevant alterations in cytologic samples by NGS analysis. Notably, clinically actionable mutations were identified in 20% of patients. In cohort 2, comprehensive mutational profiling was obtained successfully for all samples. Consistent with the findings of cohort 1, KRAS, TP53, CDKN2A, and SMAD4 were the most altered genes. Most importantly, 15% of the patients harbored actionable mutations.

CONCLUSIONS

Our findings show the feasibility of an NGS approach using both surgical specimens and cytologic samples. The model proposed in this study can be included successfully in the clinical setting for comprehensive molecular profiling of all PDAC patients irrespective of their surgical eligibility.

EUS-guided gastroenterostomy for management of malignant gastric outlet obstruction: a prospective cohort study with matched comparison with enteral stenting

BACKGROUND AND AIMS

Retrospective studies on malignant gastric outlet obstruction (mGOO) highlighted several advantages of EUS-guided gastroenterostomy (EUS-GE) over enteral stenting (ES). However, no prospective evidence is available. The aim of this study was to report on clinical outcomes of EUS-GE in a prospective cohort study, with a subgroup comparison versus ES.

METHODS

All consecutive patients endoscopically treated for mGOO between December 2020 and December 2022 in a tertiary, academic center were enrolled in a prospective registry (Prospective Registry of Therapeutic Endoscopic Ultrasound [PROTECT]; NCT04813055) and followed up every 30 days to register efficacy/safety outcomes. EUS-GE and ES cohorts were matched according to baseline frailty and oncologic disease.

RESULTS

A total of 104 patients were treated for mGOO during the study; 70 (58.6% male subjects; median age, 64 [interquartile range, 58-73] years; 75.7% pancreatic cancer, 60.0% metastatic cancer) underwent EUS-GE via the wireless simplified technique. Technical success was 97.1% and clinical success was 97.1% after a median of 1.5 (interquartile range, 1-2) days. Adverse events occurred in 9 (12.9%) patients. After a median follow-up of 105 (49-187) days, symptom recurrence was 7.6%. In the matched comparison versus ES (28 patients per arm), EUS-GE-treated patients experienced higher and faster clinical success (100% vs 75.0%, P = .006), reduced recurrences (3.7% vs 33.3%, P = .02), and a trend toward shorter time to chemotherapy.

CONCLUSIONS

In this first, prospective, single-center comparison, EUS-GE showed excellent efficacy in treating mGOO, with an acceptable safety profile and long-term patency, and several clinically significant advantages over ES. While awaiting randomized trials, these results might endorse EUS-GE as first-line strategy for mGOO, where adequate expertise is available.

Tff2 defines transit-amplifying pancreatic acinar progenitors that lack regenerative potential and are protective against Kras-driven carcinogenesis

While adult pancreatic stem cells are thought not to exist, it is now appreciated that the acinar compartment harbors progenitors, including tissue-repairing facultative progenitors (FPs). Here, we study a pancreatic acinar population marked by trefoil factor 2 (Tff2) expression. Long-term lineage tracing and single-cell RNA sequencing (scRNA-seq) analysis of Tff2-DTR-CreERT2-targeted cells defines a transit-amplifying progenitor (TAP) population that contributes to normal homeostasis. Following acute and chronic injury, Tff2+ cells, distinct from FPs, undergo depopulation but are eventually replenished. At baseline, oncogenic KrasG12D-targeted Tff2+ cells are resistant to PDAC initiation. However, KrasG12D activation in Tff2+ cells leads to survival and clonal expansion following pancreatitis and a cancer stem/progenitor cell-like state. Selective ablation of Tff2+ cells prior to KrasG12D activation in Mist1+ acinar or Dclk1+ FP cells results in enhanced tumorigenesis, which can be partially rescued by adenoviral Tff2 treatment. Together, Tff2 defines a pancreatic TAP population that protects against Kras-driven carcinogenesis.

Exploring optimal therapeutic management of STAGE IA PDAC in the era of neoadjuvant chemotherapy

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Background: Neoadjuvant chemotherapy (NAT) is currently recommended for non-metastatic pancreatic ductal adenocarcinoma (PDAC). Data on the optimal NAT duration and the proper post-surgical chemotherapy (PSC) are lacking, especially for patients (pts) who yielded a pathological stage IA. Methods: We retrospectively analyzed the outcome of PDAC pts resected between 2015 and 2020 at our institution after NAT yielding a pathologic stage of PDAC ypT1N0. Pts were analyzed basing on NAT duration (aim 1) and PSC indication (yes/no) and type (aim 2). The primary endpoint was median event-free survival (EFS) for aim 1 and median disease free-survival (DFS) for aim 2. As per secondary endpoints, overall survival (OS) and the prognostic role of clinical and pathological variables was assessed (baseline CA19.9 level; pre-operative Ca19.9 level, basal vascular involvement, grading, perineural invasion, R1 resection). Results: During the study period a total of 756 pts were resected, 363 (48%) after NAT. Of them, 72 pts (20%) achieved a pathological ypT1N0 (ypIA). Among this group 16 pts (22%) showed a T1a-T1b, 62 pts (86%) had a G1/G2 tumor, 60 pts (83%) had a R0, 36 pts (50%) had a perineural invasion and 33 (46%) had a tumor regression grade marked or completed. For aim 1 we compared 34 pts (47%) treated with NAT for not more than 4 months (Group A1) and 38 pts (53%) treated for at least 4 months (Group B1). Baseline, biochemical and radiological variables were similar between the 2 groups. No statistical difference was found in EFS (Group A1: median 46 months/ Group B1: median not reached). For aim 2 we compared 10 pts (14%) who received the same chemotherapy regimen in NAT and PSC (Group A2), 35 pts (49%) who received a different chemotherapy regimen in NAT and PSC (Group B2) and 27 (14%) pts who did not receive any PSC (Group C2). PSC were gemcitabine/nab-paclitaxel (10%) and mFOLFIRINOX (90%) in group A2, whereas gemcitabine/nab-paclitaxel (17%), mFOLFIRINOX (3%), gemcitabine (51.5%), capecitabine (17%), gemcitabine/capecitabine (8.5%), PEXG (3%) in group B2. DFS were 24 months for group B2, whereas median was not reached for group A2 e C2 (p=0.006). No statistical difference was found in OS among the groups. At multivariate analysis only grading (G3) emerged as independent factor for poor prognosis. Conclusions: In ypIA pts NAT duration and or type seem to be unrelated to the outcome. PSC performed with alternative and depotentiated chemotherapy as compared to NAT, seem to be related to a higher rate of disease recurrence. Poor differentiated/G3 tumors is confirmed as independent risk factor for poor survival in this population.

Metronomic oral cyclophosphamide as maintenance therapy in metastatic pancreatic ductal adenocarcinoma

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Background: Metastatic Pancreatic Ductal Adenocarcinoma (mPDAC) has a grim prognosis, with limited therapeutic options. In this context, treating patients (pts) with chemotherapy (CT) till progression is not supported by scientific evidence and must be weighed against quality of life impairment and cumulative toxicity. Therefore, we explored the role of metronomic oral cyclophosphamide (mCTX) as maintenance therapy (MT) in mPDAC pts. Methods: Any age mPDAC pts, with Karnofsky performance status >60 and wild-type germline BRCA1-2, who were progression-free after at least 6 months of any regimen and line CT and received mCTX (50 mg/die) MT between August 2020 and July 2022, were included in the analysis. An historical cohort (HC) of mPDAC pts, who were progression-free after 6 months of 1st-line platinum-based combination CT and did not receive MT between 2000 and 2016, was considered for exploratory comparison. Progression-free and Overall Survival (PFS and OS) were calculated from last CT administration for both cohorts. Results: 41 and 122 pts were included in mCTX and HC, respectively. Median PFS was 4.1 (range 1.5-18.4) and 3.1 (1-141) months for mCTX and HC, respectively (p= 0.003). PFS rates at 6 and 12 months were 34.7% and 11.1% in the mCTX cohort, 18.9% and 6.6% in the HC. Median OS was not reached (range 1.5-25) and 10.2 (1.3-142) months for mCTX and HC, respectively (p= 0.002). OS rates at 6 and 12 months were 96.9% and 74.6% in the mCTX cohort, 74.5% and 46.9% in the HC. Factors associated with longer PFS in the mCTX cohort were normal CA19.9 at CT start (p= 0.006), female gender (p= 0.036), no liver metastases (p= 0.01), normalized CA19.9 after CT (p= 0.01). Only 2 pts receiving mCTX had Grade 3 toxicity. Conclusions: mCTX MT extends PFS and OS of mPDAC pts not progressing after at least 6 months of CT with unremarkable toxicity in our exploratory non-randomized analysis.[Table: see text]

Guideline Application in Real world: multi-Institutional Based survey of Adjuvant and first-Line pancreatic Ductal adenocarcinoma treatment in Italy. Primary analysis of the GARIBALDI survey

BACKGROUND

Information about the adherence to scientific societies guidelines in the 'real-world' therapeutic management of oncological patients are lacking. This multicenter, prospective survey was aimed to improve the knowledge relative to 2017-2018 recommendations of the Italian Association of Medical Oncology (AIOM).

PATIENTS AND METHODS

Treatment-naive adult patients with pancreatic adenocarcinoma were enrolled. Group A received adjuvant therapy, group B received primary chemotherapy, and group C had metastatic disease. The results on patients accrued until 31 October 2019 with a mature follow-up were presented.

RESULTS

Since July 2017, 833 eligible patients of 923 (90%) were enrolled in 44 Italian centers. The median age was 69 years (range 36-89 years; 24% >75 years); 48% were female; 93% had Eastern Cooperative Oncology Group (ECOG) performance status (PS) score of 0 or 1; group A: 16%, group B: 30%; group C: 54%; 72% Nord, 13% Center, 15% South. In group A, guidelines adherence was 68% [95% confidence interval (CI) 59% to 76%]; 53% of patients received gemcitabine and 15% gemcitabine + capecitabine; median CA19.9 was 29 (range 0-7300; not reported 15%); median survival was 36.4 months (95% CI 27.5-47.3 months). In group B, guidelines adherence was 96% (95% CI 92% to 98%); 55% of patients received nab-paclitaxel + gemcitabine, 27% FOLFIRINOX, 12% gemcitabine, and 3% clinical trial; median CA19.9 was 337 (range 0-20220; not reported 9%); median survival was 18.1 months (95% CI 15.6-19.9 months). In group C, guidelines adherence was 96% (95% CI 94% to 98%); 71% of patients received nab-paclitaxel + gemcitabine, 16% gemcitabine, 8% FOLFIRINOX, and 4% clinical trial; liver and lung metastases were reported in 76% and 23% of patients, respectively; median CA19.9 value was 760 (range 0-1374500; not reported 9%); median survival was 10.0 months (95% CI 9.1-11.1 months).

CONCLUSIONS

The GARIBALDI survey shows a very high rate of adherence to guidelines and survival outcome in line with the literature. CA19.9 testing should be enhanced; nutritional and psychological counseling represent an unmet need. Enrollment to assess adherence to updated AIOM guidelines is ongoing.

Prognostic role of a novel clinical-nutritional index in pancreatic ductal adenocarcinoma: The Pancreatic Adenocarcinoma Nutritional-Clinical Index (PANCIN)

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Background: Impaired nutritional status is often associated with Pancreatic Ductal Adenocarcinoma (PDAC) and poor prognosis. Little is known on the prognostic role of nutritional variables in PDAC patients (pts) receiving chemotherapy (CT). Methods: Locally advanced or metastatic PDAC pts enrolled at our Institute in a prospective observational study (PAC-MAIN) and treated with 1st-line CT between April 2019 and July 2021 were included in the analysis. Clinical and nutritional variables entailed biohumoral parameters, bioimpedance vector analysis (BIVA)- and Computed Tomography-derived body composition. Progression-free and Overall survival (PFS and OS) were calculated from CT start to progression or death. A Multivariate Cox proportional-hazards model for PFS prediction was generated by backward selection of features with a p-value (p) ≤ 0.06. The resultant index, named PANCIN, was calculated as linear combination of the covariates (Xi are the N) and the b Cox coefficients (bi), according to the formula: PANCIN = ∑Ni=1 bi Xi Kaplan–Meier test was performed to assess the ability of PANCIN to stratify pts according to its median value for PFS and OS prediction. Results: 74 pts were included in the study. The variables retained in the model were: serum Vitamin B12 (pg/ml) [Hazard Ratio (HR)= 1.001, 95% Confidence Interval (CI) 1.0004-1.0016, p=0.002]; BIVA-derived Body Cell Mass (%) [HR= 0.94, 95% CI 0.887-1.002, p=0.058]; ECOG Performance Status (0 vs 1-2) [HR= 3.25, 95% CI 1.048-10.077, p=0.041]; Albumin (g/L) [HR= 0.91, 95% CI 0.86-0.97, p=0.002]; FAACT Score [HR= 1.041, 95% CI 1.006-1.077, p=0.022]. Median PFS was 15.3 (95% CI 7.6-21.8) and 5.8 months (95% CI 2.7-9.0) for pts with PANCIN < or ≥ -1.7768 median value respectively [HR= 3.7, 95% CI 1.9-7.0, p=0.0001]. Median OS was 23.8 (95% CI 12.6-33.3) and 10.0 months (95% CI 5.7-12.7) for pts with PANCIN < or ≥ -1.7768 respectively [HR= 4.1, 95% CI 2.1-7.9, p<0.0001]. Conclusions: PANCIN is a novel nutritional-clinical index able to predict outcome of advanced PDAC pts receiving CT. If furtherly validated, it may represent a stratification tool both in clinical practice and in prospective trials. Our findings also support the relevance of a baseline comprehensive nutritional assessment, to define tailored nutritional interventions.[Table: see text]

CTNI-21. TROTABRESIB (CC-90010) IN COMBINATION WITH CONCOMITANT TEMOZOLOMIDE PLUS RADIOTHERAPY AND ADJUVANT TEMOZOLOMIDE IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA: UPDATED RESULTS FROM A PHASE 1B/2 STUDY

Trotabresib, a novel bromodomain and extraterminal protein inhibitor, has demonstrated antitumor activity and blood–brain barrier penetration in patients with high-grade gliomas, and enhanced the antiproliferative effects of temozolomide in preclinical models. CC-90010-GBM-002 (NCT04324840) is a phase 1b/2 study investigating the addition of trotabresib to standard-of-care (SOC) concomitant temozolomide plus radiotherapy and adjuvant temozolomide, followed by maintenance trotabresib, in patients with newly diagnosed glioblastoma. The design of the dose escalation (part A) has been described previously (Vieito M, et al. SNO 2021. Abstract CTNI-51). Primary objectives of part A were to establish the safety, tolerability, and maximum tolerated dose/recommended phase 2 dose (RP2D) of trotabresib. In part A, addition of trotabresib to SOC was safe and well tolerated in the concomitant (N = 14) and adjuvant (N = 18) cohorts; the most frequent grade 3/4 treatment-related adverse event was thrombocytopenia (7/14 and 9/18 patients, respectively). The RP2D for trotabresib was 30 mg/day 4 days on/24 days off in both settings. At data cutoff (February 20, 2022), median duration of treatment was 34 weeks (concomitant cohort) and 33 weeks (adjuvant cohort); progression-free survival data are not yet mature. Trotabresib plasma pharmacokinetics and pharmacodynamics were consistent with monotherapy. At last follow-up, 6 and 5 patients remained on treatment in the concomitant and adjuvant dose-escalation cohorts, respectively, including 1 patient in cycle 20 with ongoing complete response. The ongoing randomized phase 2 dose expansion (part B; planned N = 162) is comparing concomitant trotabresib at the RP2D + SOC followed by adjuvant trotabresib at the RP2D + SOC, followed by maintenance trotabresib 45 mg/day 4 days on/24 days off, versus SOC alone in patients with newly diagnosed IDH–wild-type glioblastoma. Key objectives are to compare progression-free and overall survival, safety, and tolerability. Longer follow-up from part A and the first disclosure of data from part B will be presented.

Trotabresib (CC90010) in combination with adjuvant temozolomide or concomitant temozolomide plus radiotherapy in patients with newly diagnosed glioblastoma

Background

Standard-of-care treatment for newly diagnosed glioblastoma (ndGBM), consisting of surgery followed by radiotherapy (RT) and temozolomide (TMZ), has improved outcomes compared with RT alone; however, prognosis remains poor. Trotabresib, a novel bromodomain and extraterminal inhibitor, has demonstrated antitumor activity in patients with high-grade gliomas.

Methods

In this phase Ib, dose-escalation study (NCT04324840), we investigated trotabresib 15, 30, and 45 mg combined with TMZ in the adjuvant setting and trotabresib 15 and 30 mg combined with TMZ+RT in the concomitant setting in patients with ndGBM. Primary endpoints were to determine safety, tolerability, maximum tolerated dose, and/or recommended phase II dose (RP2D) of trotabresib. Secondary endpoints were assessment of preliminary efficacy and pharmacokinetics. Pharmacodynamics were investigated as an exploratory endpoint.

Results

The adjuvant and concomitant cohorts enrolled 18 and 14 patients, respectively. Trotabresib in combination with TMZ or TMZ+RT was well tolerated; most treatment-related adverse events were mild or moderate. Trotabresib pharmacokinetics and pharmacodynamics in both settings were consistent with previous data for trotabresib monotherapy. The RP2D of trotabresib was selected as 30 mg 4 days on/24 days off in both settings. At last follow-up, 5 (28%) and 6 (43%) patients remain on treatment in the adjuvant and concomitant settings, respectively, with 1 patient in the adjuvant cohort achieving complete response.

Conclusions

Trotabresib combined with TMZ in the adjuvant setting and with TMZ+RT in the concomitant setting was safe and well tolerated in patients with ndGBM, with encouraging treatment durations. Trotabresib 30 mg was established as the RP2D in both settings.

Modulation of the Estrogen/erbB2 Receptors Cross-talk by CDK4/6 Inhibition Triggers Sustained Senescence in Estrogen Receptor- and ErbB2-positive Breast Cancer

PURPOSE

The interplay between estrogen receptor (ER) and erbB tyrosine-kinase receptors (RTK) impacts growth and progression of ER-positive (ER+)/HER2-positive (HER2+) breast cancer and generates mitogenic signals converging onto the Cyclin-D1/CDK4/6 complex. We probed this cross-talk combining endocrine-therapy (fulvestrant), dual HER2-blockade (trastuzumab and pertuzumab), and CDK4/6-inhibition (palbociclib; PFHPert).

EXPERIMENTAL DESIGN

Cytotoxic drug effects, interactions, and pharmacodynamics were studied after 72 hours of treatment and over 6 more days of culture after drug wash-out in three ER+/HER2+, two HER2low, and two ER-negative (ER-)/HER2+ breast cancer cell lines. We assessed gene-expression dynamic and association with Ki67 downregulation in 28 patients with ER+/HER2+ breast cancer treated with neoadjuvant PFHPert in NA-PHER2 trial (NCT02530424).

RESULTS

In vitro, palbociclib and/or fulvestrant induced a functional activation of RTKs signalling. PFHPert had additive or synergistic antiproliferative activity, interfered with resistance mechanisms linked to the RTKs/Akt/MTORC1 axis and induced sustained senescence. Unexpected synergism was found in HER2low cells. In patients, Ki67 downregulation at week 2 and surgery were significantly associated to upregulation of senescence-related genes (P = 7.7E-4 and P = 1.8E-4, respectively). Activation of MTORC1 pathway was associated with high Ki67 at surgery (P = 0.019).

CONCLUSIONS

Resistance associated with the combination of drugs targeting ER and HER2 can be bypassed by cotargeting Rb, enhancing transition from quiescence to sustained senescence. MTORC1 pathway activation is a potential mechanism of escape and RTKs functional activation may be an alternative pathway for survival also in ER+/HER2low tumor. PFHPert combination is an effective chemotherapy-free regimen for ER+/HER2+ breast cancer, and the mechanistic elucidation of sensitivity/resistance patterns may provide insights for further treatment refinement.

Safety and preliminary activity results of the GATTO study, a phase Ib study combining the anti-TA-MUC1 antibody gatipotuzumab with the anti-EGFR tomuzotuximab in patients with refractory solid tumors

BACKGROUND

The phase I GATTO study (NCT03360734) explored the feasibility, tolerability and preliminary activity of combining gatipotuzumab, a novel humanized monoclonal antibody binding to the tumor-associated epitope of mucin 1 (TA-MUC1) and an anti-epidermal growth factor receptor (anti-EGFR) antibody in refractory solid tumors.

PATIENTS AND METHODS

Initially the study enrolled primary phase (PP) patients with EGFR-positive metastatic solid tumors, for whom no standard treatment was available. Patients received gatipotuzumab administered at 1400 mg every 2 weeks, 6 weeks after the start of the glyco-optimized anti-EGFR antibody tomuzotuximab at 1200 mg every 2 weeks. As this regimen was proven safe, enrollment continued in an expansion phase (EP) of patients with refractory metastatic colorectal cancer, non-small-cell lung cancer, head and neck cancer and breast cancer. Tomuzotuximab and gatipotuzumab were given at the same doses and gatipotuzumab treatment started 1 week after the first dose of the anti-EGFR antibody. Additionally, investigators could use a commercial anti-EGFR antibody in place of tomuzotuximab.

RESULTS

A total of 52 patients were enrolled, 20 in the PP and 32 in the EP. The combined treatment was well tolerated and no dose-limiting toxicity was observed in the whole study, nor related serious adverse event or death. Preliminary activity of the combination was observed, with one and four RECIST partial responses in the PP and EP, all in colorectal cancer patients. The trial was accompanied by a comprehensive translational research program for identification of biomarkers, including soluble TA-MUC1 (sTA-MUC1) in serum. In the EP, patients with baseline sTA-MUC1 levels above the median appeared to have improved progression-free survival and overall survival.

CONCLUSIONS

Combination of a TA-MUC1-targeting antibody and an EGFR-targeting antibody is safe and feasible. Interesting antitumor activity was observed in heavily pretreated patients. Future studies should test this combination together with chemotherapy and explore the potential of sTA-MUC1 as a companion biomarker for further development of the combination.

The impact of nutritional status on pancreatic cancer therapy

INTRODUCTION

Pancreatic Ductal Adenocarcinoma (PDAC) is an aggressive disease with poor outcomes. One of the reasons for the dismal prognosis resides in its impressive ability to alter the nutritional status of patients who develop malnutrition, cachexia, anorexia, and sarcopenia in most cases. The ideal way to measure such changes in PDAC patients, in order to readily identify them and avoid complications or discontinuations of treatment is a relatively unexplored area. In addition, most PDAC patients experience pancreatic exocrine insufficiency (PEI) that contributes to the complex puzzle of malnutrition and that can be treated with Pancreatic Enzyme Replacement Therapy (PERT).

AREAS COVERED

We review current knowledge on the impact of nutritional status on both surgical and medical treatments for PDAC, reporting available data on the causes of malnutrition, characteristics, and advantages of different tools to investigate nutritional status and possible strategies to improve patient outcomes.

EXPERT OPINION

All PDAC patients should receive a careful nutritional assessment at diagnosis, and this should be repeated alongside their treatment path. Screening tools and biochemical variables or scores are associated with prognosis, but bioimpedance vector analysis (BIVA) and radiological assessment of body composition seem more accurate in predicting clinical outcomes and postoperative complications.

CTNI-51. ADJUVANT TROTABRESIB, A REVERSIBLE POTENT BROMODOMAIN AND EXTRATERMINAL INHIBITOR, PLUS TEMOZOLOMIDE IN PATIENTS WITH NEWLY DIAGNOSED GLIOBLASTOMA: INTERIM RESULTS FROM A PHASE 1B DOSE-FINDING STUDY

Trotabresib (CC-90010) demonstrated antitumor activity as monotherapy in patients with advanced malignancies (Moreno et al. ESMO 2020. Abstract 5270) and enhanced the antiproliferative effects of temozolomide in preclinical studies. CC-90010-GBM-002 (NCT04324840) is a phase 1B dose-finding study investigating standard-of-care temozolomide + radiotherapy followed by adjuvant trotabresib + temozolomide or concomitant trotabresib + temozolomide + radiotherapy followed by adjuvant trotabresib + temozolomide, post-resection, in patients with newly diagnosed glioblastoma. We present interim results for adjuvant trotabresib + temozolomide. Patients received trotabresib 15, 30, or 45 mg daily (4 days on/24 days off) + temozolomide administered per label for 6 cycles, followed by trotabresib 45 mg monotherapy daily (4 days on/24 days off). Primary objectives are to establish the safety, maximum tolerated dose (MTD), and recommended phase 2 dose (RP2D) of trotabresib. Preliminary efficacy, pharmacokinetics, and pharmacodynamics are also being investigated. Of 13 patients enrolled, 5, 6, and 2 received trotabresib 15, 30, and 45 mg, respectively, plus temozolomide. Grade 3/4 treatment-related adverse events were reported in 2, 4, and 1 patients receiving trotabresib 15, 30, and 45 mg, respectively. MTD and RP2D are not yet reached; dose limiting toxicity (grade 4 thrombocytopenia) was reported in 1 patient in the 30-mg group. Of 10 evaluable patients, 1 had complete response and 7 had stable disease per RANO criteria. Trotabresib exposure increased proportionally with dose. Day 4 time to peak trotabresib concentration was 0.5–2.0 hours; mean terminal half life was 60–70 hours. Day 4 blood CCR1 RNA 2–4 hours post-dose was downregulated below baseline in the 15-mg group and ≥ 50% in the 30-mg group. Adjuvant trotabresib + temozolomide appears well tolerated, with promising preliminary efficacy. Treatment was ongoing at data cutoff in 9 patients in the adjuvant cohort; enrollment is continuing in the adjuvant and concomitant therapy dose-escalation cohorts.

Chemotherapy toxicity and activity in patients with pancreatic ductal adenocarcinoma and germline BRCA1-2 pathogenic variants (gBRCA1-2pv): a multicenter survey

BACKGROUND

Germline BRCA1-2 pathogenic variants (gBRCA1-2pv)-related pancreatic ductal adenocarcinoma (PDAC) showed increased sensitivity to DNA cross-linking agents. This study aimed at exploring safety profile, dose intensity, and activity of different chemotherapy regimens in this setting.

PATIENTS AND METHODS

gBRCA1-2pv PDAC patients of any age and clinical tumor stage who completed a first course of chemotherapy were eligible. A descriptive analysis of chemotherapy toxicity, dose intensity, response, and survival outcomes was performed.

RESULTS

A total of 85 gBRCA1-2pv PDAC patients treated in 21 Italian centers between December 2008 and March 2021were enrolled. Seventy-four patients were assessable for toxicity and dose intensity, 83 for outcome. Dose intensity was as follows: nab-paclitaxel 72%, gemcitabine 76% (AG); cisplatin 75%, nab-paclitaxel 73%, capecitabine 73%, and gemcitabine 65% (PAXG); fluorouracil 35%, irinotecan 58%, and oxaliplatin 64% (FOLFIRINOX). When compared with the literature, grade 3-4 neutropenia, thrombocytopenia, and diarrhea were increased with PAXG, and unmodified with AG and FOLFIRINOX. RECIST responses were numerically higher with the three- (81%) or four-drug (73%) platinum-containing regimens that outperformed AG (41%) and oxaliplatin-based doublets (56%). Carbohydrate antigen 19.9 (CA19.9) reduction >89% at nadir was reported in two-third of metastatic patients treated with triplets and quadruplets, as opposed to 33% and 45% of patients receiving oxaliplatin-based doublets or AG, respectively. All patients receiving AG experienced disease progression, with a median progression-free survival (mPFS) of 6.4 months, while patients treated with platinum-containing triplets or quadruplets had an mPFS >10.8 months. Albeit still immature, data on overall survival seemed to parallel those on PFS.

CONCLUSIONS

Our data, as opposed to figures expected from the literature, highlighted that platinum-based regimens provoked an increased toxicity on proliferating cells, when dose intensity was maintained, or an as-expected toxicity, when dose intensity was reduced, while no change in toxicity and dose intensity was evident with AG. Furthermore, an apparently improved outcome of platinum-based triplets or quadruplets over other regimens was observed.

Treatment opportunities and future perspectives for pancreatic cancer patients with germline BRCA1-2 pathogenic variants

Personalized treatments and predictive biomarkers of pancreatic cancer (PDAC) are still lacking. Recently germline mutations in BRCA 1 and 2 genes, leading to homologous repair deficiency, have emerged as new targets for more specific and effective therapies, exploiting the increased susceptibility to platinum salts and PARP inhibitors. In addition to BRCA, pathogenic variants in PALB2 and in other genes involved in the DNA damage response pathway (DDR) represent potential targets, as well as their respective somatic alterations. This enlarged molecularly-selected population sharing the BRCAness phenotype, is expected to show a higher sensibility to a number of DNA damaging agents and DDR inhibitors. However, the possibility of new therapeutic opportunities for DDR defective PDAC patients has to face the lack of solid evidence about the proper type and timing of targeted-treatments, the potential combination strategies and most importantly, the lack of informations on the functional impact of each specific pathogenic variant on the DDR pathway. This review summarizes the current and near-future options for the clinical management of PDAC patients harboring a DDR deficiency, analyzing the state of the art of the indications of platinum salts and other cytotoxic agents in the advanced and early stage PDAC, the development of PARP inhibitors and the rational for new combinations with immunotherapy and cycle checkpoint inhibitors, as well as the strategy to overcome the development of resistance over treatments.

Activity results of the GATTO study, a phase Ib study combining the anti-TA-MUC1 antibody gatipotuzumab with the anti-EGFR tomuzotuximab or panitumumab in patients with refractory solid tumors

2522

Background: The phase I GATTO study explored the feasibility, tolerability and preliminary activity of combining Gatipotuzumab (GAT), a novel humanized monoclonal antibody binding to the tumor-associated epitope of mucin-1 (TA-MUC1), and an anti-EGFR antibody. Preclinical evidence suggests a complex interaction between TA-MUC1 and EGFR on the cell surface of epithelial tumors and synergistic antibody dependent cell cytotoxicity activity with the double targeting. Methods: Initially 20 patients with refractory metastatic disease were treated with GAT administered at 1400 mg Q2W in combination with the glyco-optimized anti-EGFR antibody Tomuzotuximab (TOM) at 1200 mg Q2W. Due to the risk of infusion related reactions, three cycles of TOM were given before start of combined treatment with GAT. After this regimen was proven safe and no DLT was observed, 30 additional patients including colorectal cancer (CRC) already treated with anti-EGFR antibodies, non-small cell lung cancer (NSCLC), head and neck and breast cancers received TOM and GAT administered at the same doses, with GAT treatment starting already one week after the first dose of the anti-EGFR antibody. As allowed in the study expansion, Panitumumab (PAN) was used in place of TOM in 9 CRC patients at investigator’s choice. Results: By the time of the final analysis in January 2021, 52 patients were enrolled, and 50 received at least one dose of both GAT and anti-EGFR antibodies. Safety was overall good and results are reported in a separate abstract. Because of the difference in treatment schedule, activity results of the two parts of the study are summarized separately. There were 2 and 4 RECIST partial responses in the first and second part of the study, all in CRC patients. In the expansion phase, the median Progression Free Survival (PFS) of CRC patients who received TOM (10) and PAN (9) was 1.9 and 5.5 months, respectively. There were 2 responses in each subgroup and the duration of response was 3.8 and 7.2 months in patients receiving TOM and PAN, respectively. The PFS for NSCLC was 5.3 months and 2 heavily pretreated patients achieved a prolonged control of disease of 10.6 and 9.4 months. The trial was accompanied by a comprehensive translational research program for identification of biomarkers, including soluble TA-MUC1 in serum. In the extension phase patients with baseline values above median appeared to have improved PFS and overall survival; this was not the case for patients of the first part of the study who received GAT only after 3 doses of TOM. Conclusions: Combination of TA-MUC1 and EGFR targeting antibody is safe and feasible. Interesting anti-tumor activity was observed in heavily pretreated CRC and NSCLC patients. Levels of soluble TA-MUC1 may have predictive value and potentially be a companion biomarker for further development of the combination Clinical trial information: NCT03360734.

Safety and tolerability results of the GATTO study, a phase Ib study combining the anti-TA-MUC1 antibody gatipotuzumab with the anti-EGFR tomuzotuximab or panitumumab in patients with refractory solid tumors

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Background: The phase I GATTO study explored the feasibility, tolerability and preliminary activity of combining gatipotuzumab (GAT), a novel humanized monoclonal antibody binding to the tumor-associated epitope of mucin-1 (TA-MUC1) and an anti-EGFR antibody. Preclinical evidence suggests a complex interaction between TA-MUC1 and EGFR on the cell surface of epithelial tumors driving carcinogenesis processes and synergistic antibody dependent cell cytotoxicity activity with the dual targeting. Methods: Initially the study enrolled in a primary phase (PP) 20 patients with EGFR positive metastatic solid tumors, for whom no standard treatment was available. The first 6 patients were enrolled into a safety run-in phase and the number of dose-limiting toxicities (DLTs) was evaluated, in order to de-escalate the doses if needed. Patients received GAT administered at 1400 mg Q2W in combination with the glyco-optimized anti-EGFR antibody tomuzotuximab (TOM) at 1200 mg Q2W. Due to the risk of infusion related reactions (IRR), the first dose of TOM was reduced to 720 mg split over 2 consecutive days and three cycles of TOM monotherapy were given before start of treatment with GAT. As this regimen was proven safe, no DLT was observed and the initial dose remained unchanged, the study was amended to enroll in an expansion phase (EP) 30 additional patients with refractory colorectal cancer (CRC), non-small cell lung cancer (NSCLC), head and neck and breast cancers. TOM and GAT were given at the same doses and GAT treatment started already one week after the first dose of the anti-EGFR antibody. Additionally investigator had the choice to use a commercial anti-EGFR antibody in place of TOM. Results: By the time of the final analysis in January 2021, 52 refractory patients were enrolled and 50 received at least one dose of both GAT and anti-EGFR antibodies. Panitumumab (PAN) was used in 9 CRC patients. Because of the difference in treatment schedule, results are summarized separately for the 20 and 30 patients in PP and EP. Overall, the combined treatment was well tolerated and no DLT was observed in the whole study, nor related SAE or death. There were no treatment emergent adverse events (TEAEs) leading to dose interruptions or reductions in the PP and 2/30 (6.7%) patients in EP stopped both TOM and GAT. 16 IRRs were reported in 8/20 (40%) PP patients, and 40 IRRs in 10 (33.3%) EP patients. Only one event of chills was severe and only 6 events were related to GAT in the EP, all others to TOM. Other frequent TEAEs were those commonly observed with anti-EGFR treatment such as skin toxicity in 17 (85%) PP and 26 (86.7%) EP patients and hypomagnesemia in 10 (50%) PP and 7 (23.3%) EP patients. Conclusions: Combination of TA-MUC1 and EGFR targeting antibody is safe and feasible. Future studies should test this combination together with chemotherapy Clinical trial information: NCT03360734.

Germinal BRCA1-2 pathogenic variants (gBRCA1-2pv) and pancreatic cancer: epidemiology of an Italian patient cohort

OBJECTIVE

Germline BRCA1-2 pathogenic variants (gBRCApv) increase the risk of pancreatic cancer and predict for response to platinating agents and poly(ADP-ribose) polymerase inhibitors. Data on worldwide gBRCApv incidence among pancreatic ductal adenocarcinoma (PDAC) patients are sparse and describe a remarkable geographic heterogeneity. The aim of this study is to analyze the epidemiology of gBRCApv in Italian patients.

MATERIALS AND METHODS

Patients of any age with pancreatic adenocarcinoma, screened within 3 months from diagnosis for gBRCApv in Italian oncologic centers systematically performing tests without any selection. For the purposes of our analysis, breast, ovarian, pancreas, and prostate cancer in a patient's family history was considered as potentially BRCA-associated. Patients or disease characteristics were examined using the χ2 test or Fisher's exact test for qualitative variables and the Student's t-test or Mann-Whitney test for continuous variables, as appropriate.

RESULTS

Between June 2015 and May 2020, 939 patients were tested by 14 Italian centers; 492 (52%) males, median age 62 years (range 28-87), 569 (61%) metastatic, 273 (29%) with a family history of potentially BRCA-associated cancers. gBRCA1-2pv were found in 76 patients (8.1%; 9.1% in metastatic; 6.4% in non-metastatic). The gBRCA2/gBRCA1 ratio was 5.4 : 1. Patients with gBRCApv were younger compared with wild-type (59 versus 62 years, P = 0.01). The gBRCApv rate was 17.1% among patients <40 years old, 10.4% among patients 41-50 years old, 9.2% among patients 51-60 years old, 6.7% among patients aged 61-70 years, and 6.2% among patients >70 years old (none out of 94 patients >73 years old). gBRCApv frequency in 845 patients <74 years old was 9%. Patients with/without a family history of potentially BRCA-associated tumors had 14%/6% mutations.

CONCLUSION

Based on our findings of a gBRCApv incidence higher than expected in a real-life series of Italian patients with incident PDAC, we recommend screening all PDAC patients <74 years old, regardless of family history and stage, due to the therapeutic implications and cancer risk prevention in patients' relatives.

Interleukin-1β-induced pancreatitis promotes pancreatic ductal adenocarcinoma via B lymphocyte-mediated immune suppression

OBJECTIVE

Long-standing chronic pancreatitis is an established risk factor for pancreatic ductal adenocarcinoma (PDAC). Interleukin-1β (IL-1β) has been associated in PDAC with shorter survival. We employed murine models to investigate the mechanisms by which IL-1β and chronic pancreatitis might contribute to PDAC progression.

DESIGN

We crossed LSL-Kras^+/G12D;Pdx1-Cre (KC) mice with transgenic mice overexpressing IL-1β to generate KC-IL1β mice, and followed them longitudinally. We used pancreatic 3D in vitro culture to assess acinar-to-ductal metaplasia formation. Immune cells were analysed by flow cytometry and immunohistochemical staining. B lymphocytes were adoptively transferred or depleted in Kras-mutant mice. B-cell infiltration was analysed in human PDAC samples.

RESULTS

KC-IL1β mice developed PDAC with liver metastases. IL-1β treatment increased Kras^+/G12D pancreatic spheroid formation. CXCL13 expression and B lymphocyte infiltration were increased in KC-IL1β pancreata. Adoptive transfer of B lymphocytes from KC-IL1β mice promoted tumour formation, while depletion of B cells prevented tumour progression in KC-IL1β mice. B cells isolated from KC-IL1β mice had much higher expression of PD-L1, more regulatory B cells, impaired CD8⁺ T cell activity and promoted tumorigenesis. IL-35 was increased in the KC-IL1β pancreata, and depletion of IL-35 decreased the number of PD-L1⁺ B cells. Finally, in human PDAC samples, patients with PDAC with higher B-cell infiltration within tumours showed significantly shorter survival.

CONCLUSION

We show here that IL-1β promotes tumorigenesis in part by inducing an expansion of immune-suppressive B cells. These findings point to the growing significance of B suppressor cells in pancreatic tumorigenesis.

Multidrug regimens for treatment of older patients with metastatic pancreatic cancer

BACKGROUND AND AIMS

Older patients with metastatic pancreatic adenocarcinoma (MPDAC) are under-represented in clinical trials.

METHODS

Our single-center, retrospective study enrolled MPDAC patients ≥ 70 treated with chemotherapy RESULTS: 105 patients were divided in groups based on the received treatments: 44 gemcitabine or capecitabine monotherapy (A), 34 nabpaclitaxel-gemcitabine (B) 27 4-drugs combinations (gemcitabine, cisplatin, capecitabine plus either nab-paclitaxel or epirubicin or docetaxel) (C). Group A: median age was 78 (70-87) and Karnofsky performance status (KPS) ≥80 was found in 84% of patients; Group B: median age 77 (71-84) and KPS ≥ 80 in 88% of patients; Group C: median age 73 (70-78) and KPS ≥ 80 in 93% of patients. Median OS was 7.9, 11.7 and 14.2 months in group A, B and C respectively; 1 and 2-year OS were 27% and 8% in group A; 44% and 5% in group B; 52% and 22% in group C. When lung metastatic only patients were excluded, patients <75 and ≥ 75 had similar OS in group A (6.4 vs 5.6 months) and in group B (12.3 vs 11.1 months). In group B grade 3 thrombocytopenia, fatigue and peripheral neuropathy were more frequent in patients ≥ 75.

CONCLUSIONS

In older patients, combination chemotherapy shows acceptable feasibility and promising efficacy.

Circulating Chromogranin A Is Cleaved Into Vasoregulatory Fragments in Patients With Pancreatic Ductal Adenocarcinoma

Chromogranin A (CgA), a secretory protein released in the blood by the neuroendocrine system, consists of a mixture of full-length molecules and fragments endowed of vasoregulatory activity. The extent and the role of CgA fragmentation were investigated in patients with locally advanced or metastatic pancreatic ductal adenocarcinoma (PDAC, n=172). Multivariate analysis showed that full-length CgA was associated with better progression free and overall survival, whereas CgA C-terminal fragmentation was associated with worse prognosis. In vitro studies showed that PDAC cells can promote the cleavage of CgA C-terminal region by activating plasminogen to plasmin. Limited digestion of full-length CgA with plasmin abolished its anti-angiogenic activity and generated pro-angiogenic molecules. The fragmentation of CgA C-terminal region was increased also in murine models of PDAC. In these models, the inhibition of CgA fragmentation with aprotinin, an inhibitor of plasmin and other serine proteases, or the blockade of pro-angiogenic fragments with specific antibodies inhibited the growth of PDAC implanted subcutaneously in mice. Finally, administration of full-length CgA to mice bearing orthotopic PDAC reduced tumor perfusion, as measured by contrast-enhanced ultrasound. These findings suggest that PDAC can promote the cleavage of circulating CgA C-terminal region to generate fragments that regulate the tumor vascular biology and that may represent new potential therapeutic targets.

Time to CA19-9 nadir: a clue for defining optimal treatment duration in patients with resectable pancreatic ductal adenocarcinoma

BACKGROUND

Defining optimal treatment duration in patients with resectable pancreatic ductal adenocarcinoma (PDAC) receiving primary chemotherapy is an unmet need. The role of time to CA19-9 nadir and of nadir magnitude was explored in this study.

PATIENTS AND METHODS

The databases of our institution's prospective trials were queried to speculate on the time to maximum chemotherapy response. Patients with pathologically proven, metastatic (N = 356) or non-metastatic non-resected (N = 163) PDAC and elevated baseline (> 34 UI/mL) CA19-9 were analyzed. Survival curves were estimated using the Kaplan-Meier method and compared by means of the log-rank test for analyses including at least 45 patients. Multivariable Cox proportional hazards model was used to estimate clinical features for their association with OS. All probability values were from two-sided tests.

RESULTS

Time to CA19-9 nadir was ≥ 4 months in 184 of 346 (53%) metastatic and 121 of 163 (74%) non-metastatic patients (p = 0.002). The likelihood of a later nadir was higher with taxane-based chemotherapy as compared to taxane-free combinations (73% versus 56%; p = 0.02). Both metastatic and non-metastatic patients had significantly longer survival when nadir occurred later. Patients with a larger CA19-9 nadir magnitude had significantly longer survival. Metastatic patients with CA19-9 reduced by < 50%, 50-89%, or > 89% and had a median survival of 7.4, 9.8, and 14.7 months, respectively (p ≤ 0.001 for all comparisons). The corresponding figures for non-metastatic patients were 10.6; 17.0; and 18.7 months, respectively (p ≤ 0.02 for < 50% versus 50-89% or > 89%; p = 0.14 for 50-89% versus > 89%). Multivariable analyses showed that time to CA19-9 nadir but not CA19-9 nadir magnitude was independently predictive of survival.

CONCLUSION

The present study suggests that a 4-6 months program might be a more suitable candidate for prospective assessment in comparison to shorter pre-defined period in patients who are candidates to surgery after primary chemotherapy.

Cholinergic Signaling via Muscarinic Receptors Directly and Indirectly Suppresses Pancreatic Tumorigenesis and Cancer Stemness

In many solid tumors, parasympathetic input is provided by the vagus nerve, which has been shown to modulate tumor growth. However, whether cholinergic signaling directly regulates progression of pancreatic ductal adenocarcinoma (PDAC) has not been defined. Here, we found that subdiaphragmatic vagotomy in LSL-Kras +/G12D;Pdx1-Cre (KC) mice accelerated PDAC development, whereas treatment with the systemic muscarinic agonist bethanechol restored the normal KC phenotype, thereby suppressing the accelerated tumorigenesis caused by vagotomy. In LSL-Kras +/G12D;LSL-Trp53 +/R172H;Pdx1-Cre mice with established PDAC, bethanechol significantly extended survival. These effects were mediated in part through CHRM1, which inhibited downstream MAPK/EGFR and PI3K/AKT pathways in PDAC cells. Enhanced cholinergic signaling led to a suppression of the cancer stem cell (CSC) compartment, CD11b+ myeloid cells, TNFα levels, and metastatic growth in the liver. Therefore, these data suggest that cholinergic signaling directly and indirectly suppresses growth of PDAC cells, and therapies that stimulate muscarinic receptors may be useful in the treatment of PDAC.Significance: Subdiaphragmatic vagotomy or Chrm1 knockout accelerates pancreatic tumorigenesis, in part via expansion of the CSC compartment. Systemic administration of a muscarinic agonist suppresses tumorigenesis through MAPK and PI3K/AKT signaling, in early stages of tumor growth and in more advanced, metastatic disease. Therefore, CHRM1 may represent a potentially attractive therapeutic target. Cancer Discov; 8(11); 1458-73. ©2018 AACR. This article is highlighted in the In This Issue feature, p. 1333.

Chemotherapy in elderly patients with pancreatic cancer: Efficacy, feasibility and future perspectives

By 2030 70% of newly diagnosed pancreatic ductal adenocarcinoma (PDAC) will occur in older adults. Elderly patients, defined by the World Health Organization (WHO) as people older than 65 years, represent a heterogeneous group with different biological and functional characteristics that need personalized anticancer treatments. Since older patients are under-represented in randomized phase III trials, their management is mostly extrapolated from studies performed in younger patients, without robust evidence-based recommendations. However, data from retrospective studies and case-control series show that elderly may benefit from chemotherapy in both the adjuvant and advanced disease settings. Although with discordant results, gemcitabine-based treatment and dose-adapted fluorouracil combination regimens seem to be effective and well tolerated in this subset of patients. A proper balance of potential treatment benefits and side effects represent the crucial point for managing elderly patients with PDAC. Therefore an appropriate patient selection is essential to maximize the therapeutic benefit in the older population: randomized studies aiming to better standardizing fitness parameters and implementing the routine use of comprehensive geriatric assessments are strongly warranted. In this light, the detection of molecular prognostic markers able to detect patients who may benefit more from oncological treatments should be a primary endpoint of age-focused clinical trials. Altogether, the field of geriatric oncology will expand in the next years, and the clinical management of elderly patients affected by PDAC will become a major public health issue.

β2 Adrenergic-Neurotrophin Feedforward Loop Promotes Pancreatic Cancer

Catecholamines stimulate epithelial proliferation, but the role of sympathetic nerve signaling in pancreatic ductal adenocarcinoma (PDAC) is poorly understood. Catecholamines promoted ADRB2-dependent PDAC development, nerve growth factor (NGF) secretion, and pancreatic nerve density. Pancreatic Ngf overexpression accelerated tumor development in LSL-Kras+/G12D;Pdx1-Cre (KC) mice. ADRB2 blockade together with gemcitabine reduced NGF expression and nerve density, and increased survival of LSL-Kras+/G12D;LSL-Trp53+/R172H;Pdx1-Cre (KPC) mice. Therapy with a Trk inhibitor together with gemcitabine also increased survival of KPC mice. Analysis of PDAC patient cohorts revealed a correlation between brain-derived neurotrophic factor (BDNF) expression, nerve density, and increased survival of patients on nonselective β-blockers. These findings suggest that catecholamines drive a feedforward loop, whereby upregulation of neurotrophins increases sympathetic innervation and local norepinephrine accumulation.

Abstract LB-144: Tff2 labels pancreatic progenitors that lack proliferative potential during tissue regeneration but can serve as the origin of pancreatic cancer

While controversy over the existence of adult pancreatic stem cells persists, it is now appreciated that the acinar compartment of the pancreas harbors heterogeneous progenitors. Recent single-cell analysis also demonstrated the presence of molecularly distinct, albeit morphologically identical, acinar cell sub-lineages. Previously, using lineage-tracing approach, we reported the Dclk1+ facultative progenitors that are critical for pancreatic regeneration. Here, we identified a different pancreatic progenitor-like subpopulation which is labelled by trefoil factor 2 (Tff2), a known progenitor marker and capable of tracing multiple cell lineages in the stomach. In addition, Tff2 molecules have been shown to play a suppressive role in PDAC progression. We utilized constitutive Tff2Cre and inducible Tff2CreERT2-DTR mice which were generated through modification of a BAC allele. We crossed Tff2CreERT2-DTR with reporter mice (R26R-mTmG, -tdTomato) to trace Tff2 labeled cells, and found that Tff2 labels ~2 % of the overall population in the adult acinar compartment, which showed slow proliferation (1 year, descendants &lt;5%) with a proliferative peak at around 6 months. Analysis of Cre recombination of both Tff2CreERT2-DTR and Cre mice revealed proliferative heterogeneity among Tff2+ acinar cells. Interestingly, following caerulein-induced injury, pancreatic ductal ligation and partial pancreatectomy, Tff2 labeled cells, distinct from Dclk1+ acinar cells, did not show increased proliferation but remained unchanged or decreased in the number of clones, suggesting that Tff2+ progenitors are not the major drivers of acinar regeneration in response to injurious stimuli. Quantitative RT-PCR analysis revealed higher expression of Sox9 and c-Met in Tff2+ acinar progenitor-like cells vs. Tff2- acinar cells. Targeted expression of KRasG12D in Tff2+ cells in the adult pancreas through crosses to LSL-KRasG12D mice led to a spectrum of mPanIN formation from 6 to 12 months, but no progression to PDAC within 12 months. Upon caerulein treatment, the progression of PanIN lesions was dramatically accelerated, with approximately 30% of the mice developing aggressive PDAC. Embryonic activation of KRasG12D in Tff2+ cells in Tff2cre mice spontaneously initiated a robust PDAC in the absence of cerulein. Clonal expansion labeled by a multicolor reporter (R26R-Brainbow2.1) showed that PDACs were polyclonal, derived from multiple Tff2+ progenitor cells. Acute pancreatitis induced by caeruelein accelerated tumor development, and significantly shortened the survival of Tff2cre;LSL-Kras mice. Altogether, Tff2 labels a subpopulation of the larger acinar progenitor pool. Tff2+ acinar cells are not facultative progenitors but can serve as a cell of origin for PDAC.

Citation Format: Zhengyu Jiang, Bernhard W. Renz, Marina Macchini, Tanaka Takayuki, Ryota Takahashi, Giovanni Valenti, Woosook Kim, Wenju Chang, Yoku Hayakawa, Kosuke Sakitani, Moritz Middelhoff, Zinaida Dubeykovskaya, Timothy Chu, Karan Nagar, Yagnesh Tailor, Chythra R. Chandregowda, Akanksha Anand, Samuel Asfaha, Alina C. Iuga, Timothy C. Wang. Tff2 labels pancreatic progenitors that lack proliferative potential during tissue regeneration but can serve as the origin of pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-144. doi:10.1158/1538-7445.AM2017-LB-144

Nerve Growth Factor Promotes Gastric Tumorigenesis through Aberrant Cholinergic Signaling

Within the gastrointestinal stem cell niche, nerves help to regulate both normal and neoplastic stem cell dynamics. Here, we reveal the mechanisms underlying the cancer-nerve partnership. We find that Dclk1⁺ tuft cells and nerves are the main sources of acetylcholine (ACh) within the gastric mucosa. Cholinergic stimulation of the gastric epithelium induced nerve growth factor (NGF) expression, and in turn NGF overexpression within gastric epithelium expanded enteric nerves and promoted carcinogenesis. Ablation of Dclk1⁺ cells or blockade of NGF/Trk signaling inhibited epithelial proliferation and tumorigenesis in an ACh muscarinic receptor-3 (M3R)-dependent manner, in part through suppression of yes-associated protein (YAP) function. This feedforward ACh-NGF axis activates the gastric cancer niche and offers a compelling target for tumor treatment and prevention.

Dclk1 Defines Quiescent Pancreatic Progenitors that Promote Injury-Induced Regeneration and Tumorigenesis

The existence of adult pancreatic progenitor cells has been debated. While some favor the concept of facultative progenitors involved in homeostasis and repair, neither a location nor markers for such cells have been defined. Using genetic lineage tracing, we show that Doublecortin-like kinase-1 (Dclk1) labels a rare population of long-lived, quiescent pancreatic cells. In vitro, Dclk1+ cells proliferate readily and sustain pancreatic organoid growth. In vivo, Dclk1+ cells are necessary for pancreatic regeneration following injury and chronic inflammation. Accordingly, their loss has detrimental effects after cerulein-induced pancreatitis. Expression of mutant Kras in Dclk1+ cells does not affect their quiescence or longevity. However, experimental pancreatitis converts Kras mutant Dclk1+ cells into potent cancer-initiating cells. As a potential effector of Kras, Dclk1 contributes functionally to the pathogenesis of pancreatic cancer. Taken together, these observations indicate that Dclk1 marks quiescent pancreatic progenitors that are candidates for the origin of pancreatic cancer.