BACKGROUND: 5-Fluorouracil (5-FU) is a major component of gastrointestinal cancer treatments. In multidrug regimens such as FOLFOX, FOLFIRI, and FOLFIRINOX, 5-FU is commonly administered as a bolus followed by an infusion. However, the pharmacologic rationale for incorporating the 5-FU bolus in these regimens is unclear, and there are other effective regimens for gastrointestinal cancers that do not include the bolus. The purpose of this study was to determine whether omission of the 5-FU bolus was associated with a difference in survival and toxicity.
METHODS: A real-world database from Flatiron Health was queried for patients with advanced colorectal, gastroesophageal, and pancreatic cancers who received first-line FOLFOX, FOLFIRI, and FOLFIRINOX regimens. Cox proportional hazards and Kaplan-Meier analyses were performed to compare survival outcomes between patients who received the 5-FU bolus and those who did not. Inverse probability of treatment weighted (IPTW) analysis was performed to adjust for treatment selection bias.
RESULTS: This study included 11,765 patients with advanced colorectal (n=8,670), gastroesophageal (n=1,481), and pancreatic (n=1,614) cancers. Among all first-line 5-FU multidrug regimens, 10,148 (86.3%) patients received a 5-FU bolus and 1,617 (13.7%) did not. After IPTW analysis, we found that omitting the bolus was not associated with a decrease in overall survival (hazard ratio, 0.99; 95% CI, 0.91-1.07; P=.74). However, omitting the bolus was associated with reductions in neutropenia (10.7% vs 22.7%; P<.01), thrombocytopenia (11.2% vs 16.1%; P<.01), and use of granulocyte colony-stimulating factors after treatment (19.6% vs 29.1%; P<.01).
CONCLUSIONS: After adjusting for baseline clinical factors, we found that omission of the 5-FU bolus from FOLFOX, FOLFIRI, and FOLFIRINOX regimens was not associated with decreased survival, but resulted in decreased toxicity and possible health care savings.

OBJECTIVE: Pancreatic cancer has a very poor prognosis with a 5-year survival rate of less than 5% among patients with distant metastasis, a figure that has not improved over many decades. Only 10 to 20% patients are candidates for curative surgery at presentation due to the aggressive nature and asymptomatic progression of pancreatic cancer. Although first-line chemotherapy, such as FOLFIRINOX and gemcitabine + nab paclitaxel, improved the median survival from 8.5 to 11.1 months, more effective treatments are immediately needed. The aim of the present study was to evaluate the efficacy of methionine restriction with oral rMETase (o-rMETase) and a low-methionine diet combined with first-line chemotherapy on a patient with stage IV metastatic pancreatic cancer.
METHODS: A 63-year-old female was diagnosed with metastatic pancreatic cancer in October 2023. The patient started FOLFIRINOX as first-line chemotherapy in combination with methionine restriction, which comprised o-rMETase 250 units twice a day and a low-methionine diet. The patient was monitored using computed tomography and CA19-9 blood tests. After five months from the start of combination therapy, the size of the primary tumor decreased by 40% along with liver-metastasis regression. The CA19-9 blood marker decreased by 86%. The patient sustains a high performance status and continues the combination therapy without severe side effects.
CONCLUSIONS: Methionine restriction consisting of o-rMETase and a low-methionine diet, in combination with first-line chemotherapy, was highly effective in a patient with inoperable stage IV pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at metastatic stage and typically treated with fluorouracil, leucovorin, irinotecan and oxaliplatin (FOLFIRINOX). Few patients benefit from this treatment. Molecular subtypes are prognostic in particularly resectable PDAC and might predict treatment response. This study aims to correlate molecular subtypes in metastatic PDAC with FOLFIRINOX responses using real-world data, providing assistance in counselling patients. We collected 131 RNA-sequenced metastatic biopsies and applied a network-based meta-analysis using published PDAC classifiers. Subsequent survival analysis was performed using the most suitable classifier. For validation, we developed an immunohistochemistry (IHC) classifier using GATA6 and keratin-17 (KRT17), and applied it to 86 formalin-fixed paraffin-embedded samples of advanced PDAC. Lastly, GATA6 knockdown models were generated in PDAC organoids and cell lines. We showed that the PurIST classifier was the most suitable classifier. With this classifier, classical tumors had longer PFS and OS than basal-like tumors (PFS: 216 vs. 78 days, p = 0.0002; OS: 251 vs. 195 days, p = 0.049). The validation cohort showed a similar trend. Importantly, IHC GATA6low patients had significantly shorter survival with FOLFIRINOX (323 vs. 746 days, p = 0.006), but no difference in non-treated patients (61 vs. 54 days, p = 0.925). This suggests that GATA6 H-score predicts therapy response. GATA6 knockdown models did not lead to increased FOLFIRINOX responsiveness. These data suggest a predictive role for subtyping (transcriptomic and GATA6 IHC), though no direct causal relationship was found between GATA6 expression and chemoresistance. GATA6 immunohistochemistry should be seamlessly added to current diagnostics and integrated into upcoming clinical trials.

BACKGROUND: The efficacy and safety of conversion surgery (CS) after FOLFIRINOX or gemcitabine plus nab-paclitaxel (GnP) chemotherapy in patients with initially unresectable pancreatic cancer (PC) remains unclear.
METHODS: This multicenter retrospective cohort study enrolled patients, between 2014 and 2018, with initially locally advanced or metastatic PC who were considered candidates for CS following FOLFIRINOX or GnP chemotherapy. They were classified into surgery (207 patients [194 resection and 13 exploratory laparotomy only]) and continued chemotherapy (10 patients, control) groups. The primary endpoint was overall survival (OS) from the day of diagnosis of potentially curative resection on imaging studies, with an expected hazard ratio (HR) of 0.7.
RESULTS: OS in the surgery group was longer than that in the control group (HR, 0.47; 95% confidence interval [CI]: 0.24-0.93). The median OS was 34.4 (95% CI: 27.9-43.4) and 19.8 (95% CI: 14.9-31.1) months in the surgery and control groups, respectively. The Clavien-Dindo grade ≥ IIIa postoperative complication and in-hospital mortality rates were 19.6% and 0.5%, respectively. Multivariate analysis revealed that preoperative chemotherapy duration was not associated with OS.
CONCLUSIONS: CS, following a favorable response to FOLFIRINOX or GnP chemotherapy, improved initially unresectable PC prognosis (specifically, OS), regardless of the chemotherapy duration.

Pancreatic ductal adenocarcinoma is a cancer disease with a very poor prognosis, which poses the third-leading cause of cancer-related deaths and whose incidence and mortality have been predicted to increase significantly in the upcoming years. Almost 80% of patients are diagnosed with advanced unresectable disease and therefore rely on palliative anticancer treatment with limited efficacy. However, even in case of 10-20 % of patients who have successfully undergone radical surgical resection of the localized disease and subsequent adjuvant chemotherapy, the vast majority will relapse within 2-3 years of surgery. The reasons can be found in late diagnosis due to the prolonged clinically asymptomatic course of the disease, complicated anatomical localization, significant tumor heterogeneity, which makes it difficult to test new drugs and, last but not least, in the presence of dense tumor stroma, that complicates the access of cytostatics and targeted drugs into the tumor tissue. Here we present a summary of current treatment options of localized and advanced pancreatic cancer, including molecular diagnostics and targeted treatment of small patients subgroups.

BACKGROUND: Germline breast cancer susceptibility gene (gBRCA) mutation in patients with pancreatic cancer (PC) is not common in clinical practice. Therefore, factors that efficiently show gBRCA mutations and the real-world outcomes of olaparib maintenance therapy have not been fully established. In the present study, we clarified the indicators for the effective detection of gBRCA mutation and the efficacy and safety of olaparib as maintenance therapy.
METHODS: We retrospectively analyzed 84 patients with PC who underwent gBRCA testing (BRACAnalysis, Myriad Genetics, Salt Lake City, UT, USA) at our institute between January 2021 and March 2022. For each patient, clinical data were extracted from medical records.
RESULTS: The median patient age was 64 y (29-85 y), and 41 patients (48.8%) were male. The gBRCA mutations were identified in 10 (11.9%) patients; two patients had BRCA1 mutation and eight had BRCA2 mutation. All patients with gBRCA mutation had a family history of any cancer, and eight of them had a family history of Hereditary Breast and Ovarian Cancer syndrome (HBOC)-related cancer. The gBRCA mutation rate was higher for patients with PC with a family history of HBOC-related cancer compared to that in patients with PC having a family history of other cancers and no family history of cancer (22.9% vs. 4.1%; P = 0.014). In our study, eight out of 10 patients with gBRCA-positive PC received olaparib after platinum-based chemotherapy. The best responses to platinum-based chemotherapy included a complete response in one patient (12.5%) and a partial response in seven patients (87.5%). The median duration of treatment with platinum-based chemotherapy plus olaparib was 17.5 months (8-87 months), and the duration of treatment with olaparib maintenance therapy was 11 months (1-30 months). During olaparib maintenance therapy, three patients showed no disease progression. One of these three patients underwent conversion surgery after receiving olaparib for 12 months.
CONCLUSIONS: The gBRCA testing should be considered proactively, especially in patients with PC with a family history of HBOC-related cancer.

The optimal treatment strategy for neoadjuvant chemotherapy in elderly patients with pancreatic cancer (PC) remains unclear. Hence, this study was aimed at evaluating the safety and feasibility of neoadjuvant-modified FOLFIRINOX (mFOLFIRINOX) in elderly patients with PC. We retrospectively collected data from 62 patients who received neoadjuvant mFOLFIRINOX between May 2015 and October 2023 and comparatively analyzed the clinicopathological data and outcomes between the non-elderly group (age: <75 years) and elderly group (age: >75 years). The non-elderly and elderly groups comprised 39 and 23 patients, respectively. Although elevated levels of aspartate aminotransferase (p = 0.0173) and alanine aminotransferase (p = 0.0378) and nausea (p = 0.0177) were more frequent in the elderly group, the incidence of severe adverse events was similar between the groups. Intergroup differences in resection rate (p = 0.3381), postoperative severe complication rates (p = 0.2450), and postoperative hospital stay (p = 0.3496) were not significant. Furthermore, no significant intergroup differences were found in survival in either the whole or the resection cohorts. The perioperative and postoperative outcomes of elderly patients treated with neoadjuvant mFOLFIRINOX were comparable with those of non-elderly patients. Neoadjuvant mFOLFIRINOX should be considered a feasible option for elderly patients with PC.

This study aimed to compare second-line treatment outcomes for patients with unresectable pancreatic cancer previously treated with gemcitabine plus nab-paclitaxel (GnP) therapy. We conducted an integrated analysis of two retrospective studies included 318 patients receiving nanoliposomal irinotecan + 5-fluorouracil/folinic acid (NFF) (n = 102), S-1 (n = 57), or FOLFIRINOX (n = 14) as second-line treatment. Median overall survival (OS) in the NFF group was 9.08 months, significantly better than S-1 (4.90 months, P = 0.002). FOLFIRINOX had a median OS of 4.77 months, not statistically different from NFF. Subgroup analyses of OS indicated NFF was generally superior, however, a statistical interaction was observed between the treatment regimen in serum Alb < 3.5 g/dL (P = 0.042) and serum CRP ≥ 0.3 mg/dL (P = 0.006). Median progression-free survival (PFS) was 2.93 months for NFF, significantly better than S-1 (2.53 months, P = 0.024), while FOLFIRINOX had a comparable PFS (3.04 months, P = 0.948). Multivariate analysis identified the serum CRP, serum CA19-9, duration of first-line GnP therapy, and use (yes/no) of S-1 for second-line treatment as independent predictors for OS. This study concludes that second-line NFF therapy demonstrated a more favorable OS compared to S-1 therapy, however, it is still important to consider the patient background characteristics while selecting the most appropriate treatment.

OBJECTIVE: The standard treatment of T2-T3 rectal adenocarcinoma is radical proctectomy by total mesorectal excision often combined with some neoadjuvant treatment. To reduce morbidity of this surgery, organ preservation strategy using various combination of radiotherapy, chemotherapy and local excision is gaining interest. Some randomized trials have proven the feasibility of such approaches. The OPERA trial demonstrated, for T2 T3<5cm diameter low-middle rectum, that a contact X-ray brachytherapy boost of 90Gy in three fractions over 4 weeks was able to achieve a planned organ preservation in 81% of patients at 3years with 97% success for tumour smaller than 3cm treated with contact X-ray brachytherapy boost first. To try to expand organ preservation to larger tumours we set up a feasibility trial in T2-T3 tumours using total neoadjuvant treatment and a contact X-ray brachytherapy boost.
METHODS: The trial was approved by the institutional review board of Nice. Inclusion criteria were operable patients, 75years or less, adenocarcinoma of the low-middle rectum staged T2c-T3N0 larger than 3.5cm and less than 6cm in diameter or T2-T3N1 less than 6cm in diameter. Treatment started in all cases with neoadjuvant chemotherapy associating 5-fluoro-uracile, irinotecan and oxaliplatin (\'folfirinox\' regimen, four to six cycles). In case of good tumour response after four cycles, a contact X-ray brachytherapy boost (delivering 90Gy in three fractions) was given followed by chemoradiotherapy (external beam radiotherapy delivering 50Gy, with concurrent capecitabine). After six cycles if only a partial response (tumour still larger than 3cm) was seen, chemoradiotherapy was given and contact X-ray brachytherapy boost was delivered after that. At the end of this total neoadjuvant treatment a watch and wait strategy was decided in case of clinical complete response or radical proctectomy by total mesorectal excision for partial response.
RESULTS: Between July 2019 and October 2022, 14 patients were included; median age was 66years (range: 51-77years), there were nine male and five female, two T2 N1 tumours, seven T3N0, and five T3N1, all were M0. Median tumour diameter was 40mm (range: 11-50mm); three tumours had a circumferential extension greater than 50%. Seven patients received four folfirinox cycles and seven had six cycles. Contact X-ray brachytherapy boost was given during folfirinox chemotherapy before chemoradiotherapy in 11 patients (and after in three). The tolerance was good, with no grade 4-5 toxicity. The main grade 3 early toxicity was in relation with the folfirinox regimen. A clinical complete response was seen in 12 patients at the end of the total neoadjuvant treatment (85%). All these patients are alive and have preserved their rectum with a mean follow-up time of 17.8months (range: 6-48months) and a good bowel function (low anterior rectal resection syndrome score below 30). The main contact X-ray brachytherapy boost toxicity was radiation ulceration in three patients that usually healed within 6 months, sometimes necessitating hyperbaric oxygen.
CONCLUSIONS: The preliminary results of this feasibility study show that early tolerance of these intensive total neoadjuvant treatment is compatible with an acceptable toxicity. The high rate of organ preservation in this intermediate group of T2-T3 tumours is encouraging and is a good argument to start the next randomized TRESOR trial that will aim at achieving a 65% of 3-year survival with organ preservation in this intermediate tumour group.

OBJECTIVE: The combination of bevacizumab and FOLFIRINOX is used in patients with RAS-mutant metastatic colorectal cancer (RASm-mCRC). Regorafenib, an oral multi-tyrosine kinase inhibitor, has antiangiogenic properties, cytostatic effects and also true cytotoxic effects, unlike bevacizumab. The aim of this study was to determine the maximum tolerated dose (MTD) and the recommended phase 2 dose (RP2D) of the regorafenib-FOLFIRINOX combination in patients with RASm-mCRC.
METHODS: The FOLFIRINOX-R trial was a phase 1/2 study where the dose-escalation part (3 + 3 design with three dose levels, DLs) was completed before its early termination. FOLFIRINOX (14-day cycle) included oxaliplatin (standard dose), folinic acid, fluorouracil and irinotecan (150 or 180 mg/m²). Regorafenib (120 or 160 mg daily) was given from day 4 to day 10 of each cycle. Dose-limiting toxicity (DLT) was studied in the first three cycles. Eligibility criteria included ECOG performance status ≤ 1 and not previously treated RASm-mCRC.
RESULTS: Thirteen patients (median age: 65 years; min-max: 40-76) were enrolled. DLT could not be evaluated in one patient (DL3) due to poor observance. The median treatment duration and median follow-up were 6.2 (min-max: 2.3-10) and 13.4 (min-max: 3.8-18.0) months, respectively. Dose was modified in 12/13 (92%) patients. One grade 3 hypokalemia occurred at DL2. MTD was not reached at DL3. Grade 3 diarrhea was recorded in 7/13 patients (13 events) equally distributed in all DLs.
CONCLUSIONS: The RP2D for this regorafenib-FFX combination could not be determined due to a high prevalence of grade 3 diarrhea related to treatment as advised by our Independent Data Monitoring Committee.
BACKGROUND: ClinicalTrials.gov : NCT03828799.