Intratumoral NKT cell accumulation promotes antitumor immunity in pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDA) is a potentially lethal disease lacking effective treatments. Its immunosuppressive tumor microenvironment (TME) allows it to evade host immunosurveillance and limits response to immunotherapy. Here, using the mouse KRT19-deficient (sgKRT19-edited) PDA model, we find that intratumoral accumulation of natural killer T (NKT) cells is required to establish an immunologically active TME. Mechanistically, intratumoral NKT cells facilitate type I interferon (IFN) production to initiate an antitumor adaptive immune response, and orchestrate the intratumoral infiltration of T cells, dendritic cells, natural killer cells, and myeloid-derived suppressor cells. At the molecular level, NKT cells promote the production of type I IFN through the interaction of their CD40L with CD40 on myeloid cells. To evaluate the therapeutic potential of these observations, we find that administration of folinic acid to mice bearing PDA increases NKT cells in the TME and improves their response to anti-PD-1 antibody treatment. In conclusion, NKT cells have an essential role in the immune response to mouse PDA and are potential targets for immunotherapy.

Preoperative Treatment of Locally Advanced Rectal Cancer.

BACKGROUND: Pelvic radiation plus sensitizing chemotherapy with a fluoropyrimidine (chemoradiotherapy) before surgery is standard care for locally advanced rectal cancer in North America. Whether neoadjuvant chemotherapy with fluorouracil, leucovorin, and oxaliplatin (FOLFOX) can be used in lieu of chemoradiotherapy is uncertain. METHODS: We conducted a multicenter, unblinded, noninferiority, randomized trial of neoadjuvant FOLFOX (with chemoradiotherapy given only if the primary tumor decreased in size by <20% or if FOLFOX was discontinued because of side effects) as compared with chemoradiotherapy. Adults with rectal cancer that had been clinically staged as T2 node-positive, T3 node-negative, or T3 node-positive who were candidates for sphincter-sparing surgery were eligible to participate. The primary end point was disease-free survival. Noninferiority would be claimed if the upper limit of the two-sided 90.2% confidence interval of the hazard ratio for disease recurrence or death did not exceed 1.29. Secondary end points included overall survival, local recurrence (in a time-to-event analysis), complete pathological resection, complete response, and toxic effects. RESULTS: From June 2012 through December 2018, a total of 1194 patients underwent randomization and 1128 started treatment; among those who started treatment, 585 were in the FOLFOX group and 543 in the chemoradiotherapy group. At a median follow-up of 58 months, FOLFOX was noninferior to chemoradiotherapy for disease-free survival (hazard ratio for disease recurrence or death, 0.92; 90.2% confidence interval [CI], 0.74 to 1.14; P = 0.005 for noninferiority). Five-year disease-free survival was 80.8% (95% CI, 77.9 to 83.7) in the FOLFOX group and 78.6% (95% CI, 75.4 to 81.8) in the chemoradiotherapy group. The groups were similar with respect to overall survival (hazard ratio for death, 1.04; 95% CI, 0.74 to 1.44) and local recurrence (hazard ratio, 1.18; 95% CI, 0.44 to 3.16). In the FOLFOX group, 53 patients (9.1%) received preoperative chemoradiotherapy and 8 (1.4%) received postoperative chemoradiotherapy. CONCLUSIONS: In patients with locally advanced rectal cancer who were eligible for sphincter-sparing surgery, preoperative FOLFOX was noninferior to preoperative chemoradiotherapy with respect to disease-free survival. (Funded by the National Cancer Institute; PROSPECT ClinicalTrials.gov number, NCT01515787.).

Combining CD40 agonist mitazalimab with mFOLFIRINOX in previously untreated metastatic pancreatic ductal adenocarcinoma (OPTIMIZE-1): a single-arm, multicentre phase 1b/2 study.

BACKGROUND: Current systemic therapies for metastatic pancreatic ductal adenocarcinoma are associated with poor outcomes with a 5-year overall survival rate under 5%. We aimed to assess the safety and antitumour activity of mitazalimab, a human CD40 agonistic IgG1 antibody, with modified FOLFIRINOX (mFOLFIRINOX; fluorouracil, leucovorin, oxaliplatin, and irinotecan), in chemotherapy-naive patients with metastatic pancreatic ductal adenocarcinoma. METHODS: OPTIMIZE-1 was a single-arm, multicentre, phase 1b/2 study which enrolled adults with histologically-confirmed metastatic pancreatic ductal adenocarcinoma and European Cooperative Oncology Group performance status 0 or 1 in 14 university hospitals in Belgium, France, and Spain. The primary endpoint of phase 1b was to determine the recommended phase 2 dose of intravenous mitazalimab (450 µg/kg or 900 µg/kg) when combined with intravenous mFOLFIRINOX (oxaliplatin 85 mg/m2, leucovorin 400 mg/m2, irinotecan 150 mg/m2, fluorouracil 2400 mg/m2). In the first 21-day treatment cycle, mitazalimab was administered on days 1 and 10, and mFOLFIRINOX on day 8. In subsequent 14-day cycles mitazalimab was administered 2 days after mFOLFIRINOX. The phase 2 primary endpoint was objective response rate. Activity and safety analyses were conducted on the full analysis set (all patients who received the combination of mitazalimab at the recommended phase 2 dose and mFOLFIRINOX for at least two treatment cycles) and safety set (all patients who received any study treatment), respectively. Enrolment is complete, and data represents a primary analysis of the ongoing trial. The trial is registered at Clinicaltrials.gov (NCT04888312). FINDINGS: Between Sept 29, 2021, and March 28, 2023, 88 patients were screened and 70 patients were enrolled (40 [57%] were female and 30 [43%] were male). In phase 1b, 900 µg/kg mitazalimab was determined as the recommended phase 2 dose. Overall, five patients received 450 µg/kg mitazalimab; 65 received 900 µg/kg mitazalimab. No dose-limiting toxicities were observed at 450 µg/kg, and one dose-limiting toxicity was observed at 900 µg/kg. 57 patients were evaluated for activity, and all 70 patients were included in the safety set. At data cutoff on Nov 14, 2023, median follow-up was 12·7 months (95% CI 11·1-15·7). Of the 57 patients, 29 (51%) remained on study and 18 (32%) remained on treatment. The primary endpoint (objective response rate >30%) was met (objective response rates in 23 [40%]; one-sided 90% CI ≥32 of 57 patients). The most common grade 3 or worse adverse events were neutropenia (18 [26%] of 70 patients), hypokalaemia (11 patients [16%]), and anaemia and thrombocytopenia (eight patients [11%]). Serious adverse events were reported in 29 (41%) of 70 patients, the most common being vomiting (five [7%] of 70 patients), decreased appetite (four [6%]), and diarrhoea and cholangitis (three [4%] of 70 patients for each), none considered related to mitazalimab. No treatment-related deaths were reported. INTERPRETATION: Mitazalimab with mFOLFIRINOX demonstrated manageable safety and encouraging activity, warranting continued development in a phase 3, randomised, controlled trial. The results from OPTIMIZE-1 pave the way for further exploration and confirmation of a novel immunotherapy treatment regimen for metastatic pancreatic ductal adenocarcinoma, which is a complex and aggressive cancer with very low survival rates and restricted treatment options. FUNDING: Alligator Bioscience.

5-Formyltetrahydrofolate promotes conformational remodeling in a methylenetetrahydrofolate reductase active site and inhibits its activity.

The flavoprotein methylenetetrahydrofolate reductase (MTHFR) catalyzes the reduction of N5, N10-methylenetetrahydrofolate (CH2-H4folate) to N5-methyltetrahydrofolate (CH3-H4folate), committing a methyl group from the folate cycle to the methionine one. This committed step is the sum of multiple ping-pong electron transfers involving multiple substrates, intermediates, and products all sharing the same active site. Insight into folate substrate binding is needed to better understand this multifunctional active site. Here, we performed activity assays with Thermus thermophilus MTHFR (tMTHFR), which showed pH-dependent inhibition by the substrate analog, N5-formyltetrahydrofolate (CHO-H4folate). Our crystal structure of a tMTHFR•CHO-H4folate complex revealed a unique folate-binding mode; tMTHFR subtly rearranges its active site to form a distinct folate-binding environment. Formation of a novel binding pocket for the CHO-H4folate p-aminobenzoic acid moiety directly affects how bent the folate ligand is and its accommodation in the active site. Comparative analysis of the available active (FAD- and folate-bound) MTHFR complex structures reveals that CHO-H4folate is accommodated in the active site in a conformation that would not support hydride transfer, but rather in a conformation that potentially reports on a different step in the reaction mechanism after this committed step, such as CH2-H4folate ring-opening. This active site remodeling provides insights into the functional relevance of the differential folate-binding modes and their potential roles in the catalytic cycle. The conformational flexibility displayed by tMTHFR demonstrates how a shared active site can use a few amino acid residues in lieu of extra domains to accommodate chemically distinct moieties and functionalities.

Prognostic and predictive impact of metastatic organ involvement on maintenance therapy in advanced metastatic colorectal cancer: Subgroup analysis of patients treated within the PanaMa trial (AIO KRK 0212).

Despite molecular selection, patients (pts) with RAS wildtype mCRC represent a heterogeneous population including diversity in metastatic spread. We investigated metastatic patterns for their prognostic and predictive impact on maintenance therapy with 5-fluorouracil/folinic acid ± panitumumab. The study population was stratified according to (1) number of involved metastatic sites (single vs multiple organ metastasis), liver-limited disease vs (2) liver metastasis plus one additional site, and (3) vs liver metastasis plus ≥two additional sites. Kaplan-Meier method and Cox regressions were used to correlate efficacy endpoints. Single organ metastasis was observed in 133 pts (53.6%) with 102 pts (41.1%) presenting with liver-limited disease, while multiple organ metastases were reported in 114 pts (46.0). Multiple compared to single organ metastases were associated with less favorable PFS (HR 1.48, 95% CI 1.13-1.93; P = .004) and OS (HR 1.37, 95% CI 0.98-1.93; P = .068) of maintenance therapy. While metastatic spread involving one additional extrahepatic site was not associated with clearly impaired survival compared to liver-limited disease, pts with liver metastasis plus ≥two additional sites demonstrated less favorable PFS (HR 1.92, 95% CI 1.30-2.83; P < .001), and OS (HR 2.38, 95% CI 1.51-3.76; P < .001) of maintenance therapy. Pmab-containing maintenance therapy appeared active in both pts with multiple (HR 0.58; 95% CI, 0.39-0.86; P = .006) as well as to a lesser numerical extent in pts with single organ metastasis (HR 0.83; 95% CI, 0.57-1.21; P = .332; Interaction P = .183). These data may support clinical decisions when EGFR-based maintenance therapy is considered.

Cetuximab plus FOLFOXIRI versus cetuximab plus FOLFOX as conversion regimen in RAS/BRAF wild-type patients with initially unresectable colorectal liver metastases (TRICE trial): A randomized controlled trial.

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.

Phase I trial of apatinib and paclitaxel+oxaliplatin+5-FU/levoleucovorin for treatment-naïve advanced gastric cancer.

Chinese guidelines recommend POF (paclitaxel, oxaliplatin, and 5-FU/levoleucovorin) as first-line treatment for advanced gastric cancer (AGC). Apatinib can augment the antitumor effect of paclitaxel, oxaliplatin, or fluorouracil in preclinical studies of AGC. A phase I clinical trial was conducted to evaluate the anticancer activity and maximum tolerated dose (MTD) of apatinib plus POF in treatment-naïve patients with AGC and to establish a recommended phase II dose. Participants received escalating doses of daily oral apatinib (250, 375, 500, 625, 750, and 850 mg) plus POF every 2 weeks using a conventional "3 + 3" study design. Among 21 treated patients, one experienced a dose-limiting toxicity (grade 3 skin ulceration at 850 mg). No MTD was reached. Apatinib 750 mg plus POF was recommended for phase II study. The most common grade 3-4 adverse events (AEs) were neutropenia (33.3%), mucositis (14.3%), and hand-foot syndrome (14.3%). Median progression-free and overall survival were 10.4 months (95% CI: 6.3, 14.6) and 18.4 months (95% CI: 9.8, 28.2), respectively. Apatinib up to 850 mg coadministered with POF was well tolerated with manageable AEs. The safety and anticancer activity of this regimen warrants its further investigation as first-line treatment for AGC in a larger study.

A Somatic BRCA2-Mutated Pancreatic Adenocarcinoma With Sustained Exceptional Response to Modified FOLFIRINOX.

Homologous recombination repair (HRR) pathway deficiency opens multiple therapeutic avenues within pancreatic cancer. Patients with HRR deficiency-associated gene mutations such as BRCA1, BRCA2, and PALB2 are more susceptible to platinum-based chemotherapies and in those with somatic BRCA mutations, PARP inhibitor therapy prolongs progression-free survival. The case discussed herein illustrates the therapeutic opportunities offered through the identification of HRR deficiency in pancreatic cancer, as well as the challenges associated with treatment and prevention of central nervous system metastases in long-term survivors of pancreatic cancer.

Adjuvant Gemcitabine Versus Neoadjuvant/Adjuvant FOLFIRINOX in Resectable Pancreatic Cancer: The Randomized Multicenter Phase II NEPAFOX Trial.

BACKGROUND: Although addition of adjuvant chemotherapy is the current standard, the prognosis of pancreatic cancers still remains poor. The NEPAFOX trial evaluated perioperative treatment with FOLFIRINOX in resectable pancreatic cancer. PATIENTS AND METHODS: This multicenter phase II trial randomized patients with resectable or borderline resectable pancreatic cancer without metastases into arm (A,) upfront surgery plus adjuvant gemcitabine, or arm (B,) perioperative FOLFIRINOX. The primary endpoint was overall survival (OS). RESULTS: Owing to poor accrual, recruitment was prematurely stopped after randomization of 40 of the planned 126 patients (A: 21, B: 19). Overall, approximately three-quarters were classified as primarily resectable (A: 16, B: 15), and the remaining patients were classified as borderline resectable (A: 5, B: 4). Of the 12 evaluable patients, 3 achieved partial response under neoadjuvant FOLFIRINOX. Of the 21 patients in arm A and 19 patients in arm B, 17 and 7 underwent curative surgery, and R0-resection was achieved in 77% and 71%, respectively. Perioperative morbidity occurred in 72% in arm A and 46% in arm B, whereas non-surgical toxicity was comparable in both arms. Median RFS/PFS was almost doubled in arm B (14.1 months) compared with arm A (8.4 months) in the population with surgical resection, whereas median OS was comparable between both arms. CONCLUSIONS: Although the analysis was only descriptive owing to small patient numbers, no safety issues regarding surgical complications were observed in the perioperative FOLFIRINOX arm. Thus, considering the small number of patients, perioperative treatment approach appears feasible and potentially effective in well-selected cohorts of patients. In pancreatic cancer, patient selection before initiation of neoadjuvant therapy appears to be critical.

Outcomes of Hepatic Artery-Based Therapies and Systemic Multiagent Chemotherapy in Unresectable Colorectal Liver Metastases: A Systematic Review and Meta-analysis.

BACKGROUND: Treatment of unresectable colorectal liver metastases (UCRLM) includes locoregional and systemic therapy. A comprehensive analysis capturing long-term outcomes of these treatment options has not been performed. OBJECTIVE: A systematic review and meta-analysis was performed to calculate pooled outcomes of hepatic artery infusion with systemic chemotherapy (HAI-S), transarterial chemoembolization with systemic chemotherapy (TACE-S), transarterial radioembolization with systemic chemotherapy (TARE-S), doublet (FOLFOX, FOLFIRI), and triplet chemotherapy (FOLFOXIRI). METHODS: Outcomes included overall survival (OS), progression-free survival (PFS), rate of conversion to resection (CTR), and response rate (RR). RESULTS: A total of 32, 7, 9, and 14 publications were included in the HAI-S, TACE-S, and TARE-S chemotherapy arms. The 6/12/24/36-month OS estimates for HAI-S, TACE-S, TARE-S, FOLFOX, FOLFIRI, and FOLFOXIRI were 97%/80%/54%/35%, 100%/83%/40%/14%, 82%/61%/34%/21%, 96%/83%/53%/36%, and 96%/93%/72%/55%. Similarly, the 6/12/24/36-month PFS estimates were 74%/44%/19%/14%, 66%/20%/9%/3%, 57%/23%/10%/3%, 69%/30%/12%/7%, and 88%/55%/18%/11%. The corresponding CTR and RR rates were 31, 20%, unmeasurable (TARE-S), 35, 53; and 49, 45, 45, 50, 80%, respectively. The majority of chemotherapy studies included first-line therapy and liver-only metastases, whereas most HAI-S studies were pretreated. On subgroup analysis in first-line setting with liver-only metastases, the HAI-S arm had comparable outcomes to FOLFOXIRI and outperformed doublet chemotherapy regimens. Although triplet chemotherapy appeared to outperform other arms, high toxicity and inclusion of potentially resectable patients must be considered while interpreting results. CONCLUSIONS: HAI-S and multiagent chemotherapy are effective therapies for UCRLM. To make definitive conclusions, a randomized trial with comparable patient characteristics and line of therapy will be required. The upcoming EA2222 PUMP trial may help to address this question.

Nationwide Use and Outcome of Surgery for Locally Advanced Pancreatic Cancer Following Induction Chemotherapy.

BACKGROUND: Several international high-volume centers have reported good outcomes after resection of locally advanced pancreatic cancer (LAPC) following chemo(radio)therapy, but it is unclear how this translates to nationwide clinical practice and outcome. This study aims to assess the nationwide use and outcome of resection of LAPC following induction chemo(radio)therapy. PATIENTS AND METHODS: A multicenter retrospective study including all patients who underwent resection for LAPC following chemo(radio)therapy in all 16 Dutch pancreatic surgery centers (2014-2020), registered in the mandatory Dutch Pancreatic Cancer Audit. LAPC is defined as arterial involvement > 90° and/or portomesenteric venous > 270° involvement or occlusion. RESULTS: Overall, 142 patients underwent resection for LAPC, of whom 34.5% met the 2022 National Comprehensive Cancer Network criteria. FOLFIRINOX was the most commonly (93.7%) used chemotherapy [median 5 cycles (IQR 4-8)]. Venous and arterial resections were performed in 51.4% and 14.8% of patients. Most resections (73.9%) were performed in high-volume centers (i.e., ≥ 60 pancreatoduodenectomies/year). Overall median volume of LAPC resections/center was 4 (IQR 1-7). In-hospital/30-day major morbidity was 37.3% and 90-day mortality was 4.2%. Median OS from diagnosis was 26 months (95% CI 23-28) and 5-year OS 18%. Surgery in high-volume centers [HR = 0.542 (95% CI 0.318-0.923)], ypN1-2 [HR = 3.141 (95% CI 1.886-5.234)], and major morbidity [HR = 2.031 (95% CI 1.272-3.244)] were associated with OS. CONCLUSIONS: Resection of LAPC following chemo(radio)therapy is infrequently performed in the Netherlands, albeit with acceptable morbidity, mortality, and OS. Given these findings, a structured nationwide approach involving international centers of excellence would be needed to improve selection of patients with LAPC for surgical resection following induction therapy.

Serum CEA as a Prognostic Marker for Overall Survival in Patients with Localized Pancreatic Adenocarcinoma and Non-Elevated CA19-9 Levels Treated with FOLFIRINOX as Initial Treatment: A TAPS Consortium Study.

INTRODUCTION: About 25% of patients with localized pancreatic adenocarcinoma have non-elevated serum carbohydrate antigen (CA) 19-9 levels at baseline, hampering evaluation of response to preoperative treatment. Serum carcinoembryonic antigen (CEA) is a potential alternative. METHODS: This retrospective cohort study from five referral centers included consecutive patients with localized pancreatic adenocarcinoma (2012-2019), treated with one or more cycles of (m)FOLFIRINOX, and non-elevated CA19-9 levels (i.e., < 37 U/mL) at baseline. Cox regression analyses were performed to assess prognostic factors for overall survival (OS), including CEA level at baseline, restaging, and dynamics. RESULTS: Overall, 277 patients were included in this study. CEA at baseline was elevated (≥5 ng/mL) in 53 patients (33%) and normalized following preoperative therapy in 14 patients (26%). In patients with elevated CEA at baseline, median OS in patients with CEA normalization following preoperative therapy was 33 months versus 19 months in patients without CEA normalization (p = 0.088). At time of baseline, only elevated CEA was independently associated with (worse) OS (hazard ratio [HR] 1.44, 95% confidence interval [CI] 1.04-1.98). At time of restaging, elevated CEA at baseline was still the only independent predictor for (worse) OS (HR 1.44, 95% CI 1.04-1.98), whereas elevated CEA at restaging (HR 1.16, 95% CI 0.77-1.77) was not. CONCLUSIONS: Serum CEA was elevated in one-third of patients with localized pancreatic adenocarcinoma having non-elevated CA19-9 at baseline. At both time of baseline and time of restaging, elevated serum CEA measured at baseline was the only predictor for (worse) OS. Therefore, serum CEA may be a useful tool for decision making at both initial staging and time of restaging in patients with non-elevated CA19-9.

Long-Duration Neoadjuvant Therapy with FOLFIRINOX Yields Favorable Outcomes for Patients Who Undergo Surgery for Pancreatic Cancer.

BACKGROUND: In 2023 alone, it's estimated that over 64,000 patients will be diagnosed with PDAC and more than 50,000 patients will die of the disease. Current guidelines recommend neoadjuvant therapy for patients with borderline resectable and locally advanced PDAC, and data is emerging on its role in resectable disease. Neoadjuvant chemotherapy may increase the number of patients able to receive complete chemotherapy regimens, increase the rate of microscopically tumor-free resection (R0) margin, and aide in identifying unfavorable tumor biology. To date, this is the largest study to examine surgical outcomes after long-duration neoadjuvant chemotherapy for PDAC. METHODS: Retrospective analysis of single-institution data. RESULTS: The routine use of long-duration therapy in our study (median cycles: FOLFIRINOX = 10; gemcitabine-based = 7) is unique. The majority (85%) of patients received FOLFIRINOX without radiation therapy; the R0 resection rate was 76%. Median OS was 41 months and did not differ significantly among patients with resectable, borderline-resectable, or locally advanced disease. CONCLUSIONS: This study demonstrates that in patients who undergo surgical resection after receipt of long-duration neoadjuvant FOLFIRINOX therapy alone, survival outcomes are similar regardless of pretreatment resectability status and that favorable surgical outcomes can be attained.

Radiologic Occult Metastases in Pancreatic Cancer: Analysis of Risk Factors and Survival Outcomes in the Age of Contemporary Neoadjuvant Multi-agent Chemotherapy.

BACKGROUND: Radiologic occult metastatic disease (ROMD) in patients with pancreatic ductal adenocarcinoma (PDAC) who undergo contemporary neoadjuvant chemotherapy (NAC) has not been well studied. This study sought to analyze the incidence, risk factors, and oncologic outcomes for patients who underwent the NAC approach for PDAC. METHODS: A retrospective review analyzed a prospectively maintained database of patients who had potentially resectable PDAC treated with NAC and were offered pancreatectomy at our institution from 2011 to 2022. Multivariable regression analysis was performed to assess risk factors associated with ROMD. Kaplan-Meier curves with log-rank analyses were generated to estimate time-to-event end points. RESULTS: The study enrolled 366 patients. Upfront and borderline resectable anatomic staging comprised 80% of the cohort, whereas 20% had locally advanced disease. The most common NAC regimen was FOLFIRINOX (n = 274, 75%). For 55 patients (15%) who harbored ROMD, the most common site was liver-only metastases (n = 33, 60%). The independent risk factors for ROMD were increasing CA19-9 levels during NAC (odds ratio [OR], 7.01; confidence interval [CI], 1.97-24.96; p = 0.008), indeterminate liver lesions (OR, 2.19; CI, 1.09-4.39; p = 0.028), and enlarged para-aortic lymph nodes (OR, 6.87; CI, 2.07-22.74; p = 0.002) on preoperative cross-sectional imaging. Receipt of palliative chemotherapy (p < 0.001) and eventual formal pancreatectomy (p = 0.04) were associated with survival benefit in the log-rank analysis. The median overall survival (OS) of the patients with ROMD was nearly 15 months from the initial diagnosis, with radiologic evidence of metastases occurring after a median of 2 months. CONCLUSIONS: Radiologic occult metastatic disease remains a clinical challenge associated with poor outcomes for patients who have PDAC treated with multi-agent NAC.

Liposomal irinotecan (HR070803) in combination with 5-fluorouracil and leucovorin in patients with advanced solid tumors: a phase 1b dose-escalation and expansion study.

This phase 1b study aimed to evaluate the dose-limiting toxicity (DLT), maximum tolerated dose (MTD), pharmacokinetics, and preliminary efficacy of HR070803, a novel nanoliposomal formulation of irinotecan, in combination with 5-fluorouracil and leucovorin in patients with pretreated advanced solid tumors. This study consisted of dose-escalation and expansion stages. Dose escalation was performed with a traditional 3 + 3 design; patients received intravenous infusion of HR070803 from 60 to 80 mg/m2, followed by leucovorin (200 mg/m2) and 5-fluorouracil (2000 mg/m2) every 2 weeks. In the expansion stage, patients received treatments at selected tolerable dose. Fifteen patients received treatments at 60 mg/m2 (n = 12) and 80 mg/m2 (n = 3). DLTs occurred in 2 patients at 80 mg/m2 (grade 2 neutropenia that resulted in a dose delay of ≥ 7 days, n = 1; grade 3 febrile neutropenia, n = 1). The MTD was determined to be 60 mg/m2. The most frequent HR070803related adverse events included anorexia, leukopenia, neutropenia, nausea, fatigue, and diarrhea. SN-38, the active metabolite of irinotecan, exhibited lower maximum plasma concentrations and a prolonged terminal half-life when irinotecan was administered via nanoliposome compared to conventional injection. Overall, 4 patients achieved a partial response (confirmed, n = 2), and 9 had stable disease. The MTD of HR070803 was 60 mg/m2 when infused with 5-fluorouracil and leucovorin. Nanoliposomal encapsulation modified the pharmacokinetics of irinotecan and SN-38. HR070803 with 5-fluorouracil and leucovorin demonstrated a manageable safety profile and promising antitumor efficacy in advanced solid tumors. TRIAL REGISTRATION: Clinicaltrials.gov, NCT05086848. Retrospectively registered on Oct. 12, 2021.

Impact of a non-therapeutic laparotomy in patients with locally advanced pancreatic cancer treated with induction (m)FOLFIRINOX: Trans-Atlantic Pancreatic Surgery (TAPS) Consortium study.

BACKGROUND: Surgery in selected patients with locally advanced pancreatic cancer after induction chemotherapy may have drawbacks related to surgical risks and breaks or delays in oncological treatment, in particular when curative intent resection is not possible (that is non-therapeutic laparotomy). The aim of this study was to assess the incidence and oncological impact of a non-therapeutic laparotomy in patients with locally advanced pancreatic cancer treated with induction (m)FOLFIRINOX chemotherapy. METHODS: This was a retrospective international multicentre study including patients diagnosed with pathology-proven locally advanced pancreatic cancer treated with at least one cycle of (m)FOLFIRINOX (2012-2019). Patients undergoing a non-therapeutic laparotomy (group A) were compared with those not undergoing surgery (group B) and those undergoing resection (group C). RESULTS: Overall, 663 patients with locally advanced pancreatic cancer were included (67 patients (10.1%) in group A, 425 patients (64.1%) in group B, and 171 patients (25.8%) in group C). A non-therapeutic laparotomy occurred in 28.2% of all explorations (67 of 238), with occult metastases in 30 patients (30 of 67, 44.8%) and a 90-day mortality rate of 3.0% (2 of 67). Administration of palliative therapy (65.9% versus 73.1%; P = 0.307) and median overall survival (20.4 [95% c.i. 15.9 to 27.3] versus 20.2 [95% c.i. 19.1 to 22.7] months; P = 0.752) did not differ between group A and group B respectively. The median overall survival in group C was 36.1 (95% c.i. 30.5 to 41.2) months. The 5-year overall survival rates were 11.4%, 8.7%, and 24.7% in group A, group B, and group C, respectively. Compared with group B, non-therapeutic laparotomy (group A) was not associated with reduced overall survival (HR = 0.88 [95% c.i. 0.61 to 1.27]). CONCLUSION: More than a quarter of surgically explored patients with locally advanced pancreatic cancer after induction (m)FOLFIRINOX did not undergo a resection. Such non-therapeutic laparotomy does not appear to substantially impact oncological outcomes.

The 5-formyl-tetrahydrofolate proteome links folates with C/N metabolism and reveals feedback regulation of folate biosynthesis.

Folates are indispensable for plant development, but their molecular mode of action remains elusive. We synthesized a probe, "5-F-THF-Dayne," comprising 5-formyl-tetrahydrofolate (THF) coupled to a photoaffinity tag. Exploiting this probe in an affinity proteomics study in Arabidopsis thaliana, we retrieved 51 hits. Thirty interactions were independently validated with in vitro expressed proteins to bind 5-F-THF with high or low affinity. Interestingly, the interactors reveal associations beyond one-carbon metabolism, covering also connections to nitrogen (N) metabolism, carbohydrate metabolism/photosynthesis, and proteostasis. Two of the interactions, one with the folate biosynthetic enzyme DIHYDROFOLATE REDUCTASE-THYMIDYLATE SYNTHASE 1 (AtDHFR-TS1) and another with N metabolism-associated glutamine synthetase 1;4 (AtGLN1;4), were further characterized. In silico and experimental analyses revealed G35/K36 and E330 as key residues for the binding of 5-F-THF in AtDHFR-TS1 and AtGLN1;4, respectively. Site-directed mutagenesis of AtGLN1;4 E330, which co-localizes with the ATP-binding pocket, abolished 5-F-THF binding as well as AtGLN1;4 activity. Furthermore, 5-F-THF was noted to competitively inhibit the activities of AtDHFR-TS1 and AtGLN1;4. In summary, we demonstrated a regulatory role for 5-F-THF in N metabolism, revealed 5-F-THF-mediated feedback regulation of folate biosynthesis, and identified a total of 14 previously unknown high-affinity binding cellular targets of 5-F-THF. Together, this sets a landmark toward understanding the role of folates in plant development.

Clinical Analysis of the Efficacy and Safety of Different Neoadjuvant Strategies in the Treatment of Locally Advanced Rectal Cancer.

OBJECTIVE: In this study, we retrospectively analysed the efficacy and safety of three treatment models, namely, short-course radiotherapy sequential XELOX chemotherapy, neoadjuvant mFOLFOX6 concurrent radiotherapy and long-course concurrent radiotherapy with total mesorectal excision (TME) after treatment of locally advanced rectal cancer with high-risk factors. METHODS: We collected clinical data on 177 patients with locally advanced rectal cancer (cT3-4 and/or cN+) who were treated at the Department of Abdominal Oncology of the Affiliated Cancer Hospital of Guizhou Medical University from December 2017 to December 2022. All patients were associated with 2-3 risk factors [T4b, N2, Extramural Vascular Invasion (EMVI), Mesorectal Fascia (MRF) positivity], positive lateral lymph nodes. Among them, there were 45 cases in the short course radiotherapy sequential XELOX chemotherapy group (RT + XELOX group); 64 cases in the neoadjuvant mFOLFOX6 concurrent radiotherapy group (mFOLFOX6 + CRT group); and 68 cases in the long course concurrent radiotherapy group (CRT group). The RT + XELOX group and mFOLFOX6 + CRT group completed radiotherapy and 4 cycles of neoadjuvant chemotherapy, respectively, and then rested for 1-2 weeks before TME surgery; the CRT group completed concurrent radiotherapy and then rested for 6-8 weeks before TME surgery.Adjuvant chemotherapy was conducted after surgery in each of the three groups: 2 cycles of adjuvant chemotherapy with XELOX regimen in the RT + XELOX group, 4-6 cycles of adjuvant chemotherapy with mFOLFOX6 in the mFOLFOX6 + CRT group, and 8-12 cycles of adjuvant chemotherapy with mFOLFOX6 in the CRT group.The pathological complete response rate (pCR rate), tumour downstage rate, tumour complete resection rate (R0 resection rate), local recurrence rate, distant metastasis rate, overall survival rate, incidence of adverse reactions, surgical complications and completion rate of perioperative systemic chemotherapy were compared among patients in the three groups of cases after TME. RESULTS: The pCR rate (21.95% vs 17.24% vs 5.00%, p = 0.034) and and tumour downstage rate (78.05% vs 68.97% vs 53.33%, p = 0.029) were higher in the RT + XELOX group and mFOLFOX6 + CRT group compared to the CRT group. The RT + XELOX group had a lower 3-year distant metastasis rate (14.63% vs 36.67%, p = 0.048) and improved 3-year overall survival (76.57% vs 48.56%, p < 0.001) compared to the CRT group. There was no significant reduction in the 3-year distant metastasis rate in the mFOLFOX6 + CRT group versus the CRT group (27.59% vs 36.67%, p = 0.719), and the 3-year overall survival was similar (51.23% vs 48.56%, p = 0.35). Multi-logistic regression analysis and stratified analysis showed that patients in the RT + XELOX group and mFOLFOX6 + CRT group were more likely to achieve pCR than the CRT group (RT + XELOX group: OR 7.3, 95% CI [2.6-20.8], p < 0.001; mFOLFOX6 + CRT group OR 2.9, 95% CI [1.1-7.9], p = 0.036). The completion rates of perioperative systemic chemotherapy in the RT + XELOX, mFOLFOX6 + CRT, and CRT groups were 82.93% vs. 84.48% vs. 61.67% (χ2=9.95, p = 0.007), respectively. And there were significant differences in grade 3-4 leukopenia and thrombocytopenia (incidence of leukopenia: 15.50% vs. 7.81% vs. 1.47%, p = 0.045; incidence of thrombocytopenia: 13.33% vs 7.81% vs 1.47%, p = 0.027). There was no significant difference in the incidence of intraoperative and postoperative complications among the three groups (p > 0.05). CONCLUSIONS: RT + XELOX group and mFOLFOX6 + CRT group significantly improved the near-term outcome (e.g., pCR rate) in patients with locally advanced rectal cancer with high-risk factors compared with CRT group. The RT + XELOX group also reduced the 3-year distant metastasis rate, increased the 3-year overall survival rate, and did not increase the incidence of perioperative surgical complications. It provides an effective means for the comprehensive treatment of locally advanced rectal cancer and has important clinical guidance and application value.

Association of oxaliplatin-containing adjuvant duration with post-treatment fall-related injury and fracture in patients with stage III colon cancer: a population-based retrospective cohort study.

PURPOSE: Oxaliplatin-containing adjuvant chemotherapy yields a significant survival benefit in stage III colon cancer and is the standard of care. Simultaneously, it causes dose-dependent peripheral neuropathy that may increase the risk of fall-related injury (FRI) such as fracture and laceration. Because these events carry significant morbidity and the global burden of colon cancer is on the rise, we examined the association between treatment with a full versus shortened course of adjuvant chemotherapy and post-treatment FRI and fracture. METHODS: In this overlap propensity score weighted, retrospective cohort study, we included patients aged ≥ 18 years with resected stage III colon cancer diagnosed 2007-2019 and treated with oxaliplatin-containing adjuvant chemotherapy (oxaliplatin plus a fluoropyrimidine; capecitabine [CAPOX] or 5-fluorouracil and leucovorin [FOLFOX]). Propensity score methods facilitate the separation of design from analysis and comparison of baseline characteristics across the weighted groups. Treatment groups were defined as 50% (4 cycles CAPOX/6 cycles FOLFOX) and > 85% (7-8 cycles CAPOX/11-12 cycles FOLFOX) of a maximal course of adjuvant chemotherapy to approximate the treatment durations received in the IDEA collaboration. The main outcomes were time to any FRI and time to fracture. We determined the subdistribution hazard ratios (sHR) estimating the association between FRI/fracture and treatment group, accounting for the competing risk of death. RESULTS: We included 3,461 patients; 473 (13.7%) received 50% and 2,988 (86.3%) received > 85% of a maximal course of adjuvant therapy. For post-treatment FRI, median follow-up was 4.6 years and total follow-up was 17,968 person-years. There were 508 FRI, 301 fractures, and 692 deaths. Treatment with > 85% of a maximal course of therapy conferred a sHR of 0.84 (95% CI 0.62-1.13) for post-treatment FRI and a sHR of 0.72 (95% CI 0.49-1.06) for post-treatment fracture. CONCLUSION: For patients with stage III colon cancer undergoing treatment with oxaliplatin-containing adjuvant chemotherapy, any potential neuropathy associated with longer durations of treatment was not found to result in greater rates of FRI and fracture. Within the limits of this retrospective study, our findings suggest concern about FRI, while mechanistically plausible, ought not to determine treatment duration.

Survival outcome of different treatment sequences in patients with locally advanced and metastatic pancreatic cancer.

BACKGROUND: Despite some therapeutic advances, improvement in survival rates of unresectable and/or metastatic pancreatic ductal adenocarcinoma (PDAC) has been minimal over recent decade. We aimed to evaluate the impact of different treatment sequences on clinical outcomes of advanced PDAC at our academic institution. METHODS: In this single institution retrospective analysis, we assessed characteristics and survival rates of unresectable and/or metastatic pancreatic PDAC patients who started a systemic treatment between 01/2015 and 12/2021. Survival analyses were performed by Kaplan-Meier and Cox proportional hazards model. RESULTS: The number of 285 patients received at least two lines of treatment, but only 137 patients were suitable for third-line treatment. Subgroup analysis showed that thirty-seven patients received A line (gemcitabine/nab-paclitaxel or nab-paclitaxel combined therapy to FOLFIRINOX) therapy, 37 patients received B line (nab-paclitaxel combined therapy to gemcitabine combined therapy to FOLFIRINOX) therapy, 21 patients received C line (nab-paclitaxel combined therapy to gemcitabine combined therapy to oxaliplatin or irinotecan combined therapy) therapy. Survival rates for different treatment lines were significantly different and median overall survival (OS) was 14.00, 18.00, and 14.00 months, respectively (p<0.05). CONCLUSION: Our study provides real-world evidence for the effectiveness of different treatment sequences and underscores the treatment sequences on survival outcome when considering the entire management in advanced PDAC.