Difference between carbohydrate antigen 19-9 and fluorine-18 fluorodeoxyglucose positron emission tomography in evaluating the treatment efficacy of neoadjuvant treatment in patients with resectable and borderline resectable pancreatic ductal adenocarcinoma: Results of a dual-center study

BNCT pancreatic cancer treatment strategy with glucose-conjugated boron drug

Multidisciplinary therapy centered on radical surgery for resectable pancreatic cancer is expected to prolong prognosis, but relies on CA19-9 biomarker levels to determine treatment strategy. Boron neutron capture therapy (BNCT) is a chemoradiotherapy using tumor hyperaccumulator boron drugs and neutron irradiation. The purpose of this study is to investigate novel boron drug agents for BNCT for pancreatic cancer. Bioinformatics was used to evaluate the uptake of current boron amino acid (BPA) drugs for BNCT into pancreatic cancer. The expression of the amino acid transporter LAT1, a BPA uptake transporter, was low in pancreatic cancer and even lower in high CA19-9 pancreatic cancer. In contrast, the glucose transporter was high in high CA19-9 pancreatic cancers and inversely correlated with LAT1 expression. Considering the low EPR effect in pancreatic cancer, we synthesized a small molecule Glucose-BSH, which is boron BSH bound to glucose, and confirmed its specific uptake in pancreatic cancer. uptake of Glucose-BSH was confirmed in an environment compatible with the tumor microenvironment. The therapeutic efficacy and safety of Glucose-BSH by therapeutic neutron irradiation were confirmed with BNCT. We report Glucose-BSH boron drug discovery study of a Precision Medicine BNCT with application to high CA19-9 pancreatic cancer.

Prognostic Significance of Biologic Factors in Patients with a Modest Radiologic Response to Neoadjuvant Treatment for Resectable and Borderline Resectable Pancreatic Cancers: Impact of the Combination Index of Sialyl-Lewis Antigen-Related Tumor Markers

BACKGROUND

Appropriate re-evaluation after neoadjuvant treatment (NAT) is important for optimal treatment selection. Nonetheless, determining the operative eligibility of patients with a modest radiologic response remains controversial. This study aimed to assess the prognostic significance of biologic factors for patients showing a modest radiologic response to NAT and investigate the tumor markers (TMs), CA19-9 alone, DUPAN-II alone, and their combination, to create an index that combines these sialyl-Lewis antigen-related TMs associated with treatment outcomes.

METHODS

This study enrolled patients deemed to have a "stable disease" by RECIST classification with slight progression (tumor size increase rate, ≤20%) as their radiologic response after NAT. A sialyl-Lewis-related index (sLe index), calculated by adding one fourth of the serum DUPAN-II value to the CA19-9 value, was created. The prognostic significances of CA19-9, DUPAN-II, and the sLe index were assessed in relation to postoperative outcomes.

RESULTS

An sLe index lower than the cutoff value (45.25) was significantly associated with favorable disease-free survival. Moreover, the post-NAT sLe index had a higher area under the curve value for recurrence within 24 months than the post-NAT levels of CA19-9 or DUPAN-II alone. Multivariable analysis showed that a post-NAT sLe index higher than 45.25 was the single independent predictive factor for recurrence within 24 months.

CONCLUSIONS

Additional evaluation of biologic factors can potentially enhance patient selection, particularly for patients showing a limited radiologic response to NAT. The authors' index is a simple indicator for the biologic evaluation of multiple combined sialyl-Lewis antigen-related TMs and may offer a better predictive significance.

Circulating tumor-associated antigen-specific IFNγ+4-1BB+ CD8+ T cells as peripheral biomarkers of treatment outcomes in patients with pancreatic cancer

CD8+ T cells affect the outcomes of pancreatic ductal adenocarcinoma (PDAC). Using tissue samples at pre-treatment to monitor the immune response is challenging, while blood samples are beneficial in overcoming this limitation. In this study, we measured peripheral antigen-specific CD8+ T cell responses against four different tumor-associated antigens (TAAs) in PDAC using flow cytometry and investigated their relationships with clinical features. We analyzed the optimal timing within the treatment course for effective immune checkpoint inhibition in vitro. We demonstrated that the frequency of TAA-specific IFNγ+4-1BB+ CD8+ T cells was correlated with a fold reduction in CA19-9 before and after neoadjuvant therapy. Moreover, patients with TAA-specific IFNγ+4-1BB+ CD8+ T cells after surgery exhibited a significantly improved disease-free survival. Anti-PD-1 treatment in vitro increased the frequency of TAA-specific IFNγ+4-1BB+ CD8+ T cells before neoadjuvant therapy in patients, suggesting the importance of the timing of anti-PD-1 inhibition during the treatment regimen. Our results indicate that peripheral immunophenotyping, combined with highly sensitive identification of TAA-specific responses in vitro as well as detailed CD8+ T cell subset profiling via ex vivo analysis, may serve as peripheral biomarkers to predict treatment outcomes and therapeutic efficacy of immunotherapy plus neoadjuvant chemotherapy.

Preoperative chemotherapy, radiotherapy and surgical decision-making in patients with borderline resectable and locally advanced pancreatic cancer

Surgical resection combined with systemic chemotherapy is the cornerstone of treatment for patients with localized pancreatic cancer. Upfront surgery is considered suboptimal in cases with extensive vascular involvement, which can be classified as either borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In these patients, FOLFIRINOX or gemcitabine plus nab-paclitaxel chemotherapy is currently used as preoperative chemotherapy and is eventually combined with radiotherapy. Thus, more patients might reach 5-year overall survival. Patient selection for chemotherapy, radiotherapy and subsequent surgery is based on anatomical, biological and conditional parameters. Current guidelines and clinical practices vary considerably regarding preoperative chemotherapy and radiotherapy, response evaluation, and indications for surgery. In this Review, we provide an overview of the clinical evidence regarding disease staging, preoperative therapy, response evaluation and surgery in patients with borderline resectable pancreatic cancer or locally advanced pancreatic cancer. In addition, a clinical work-up is proposed based on the available evidence and guidelines. We identify knowledge gaps and outline a proposed research agenda.

Post-neoadjuvant treatment pancreatic cancer resectability and outcome prediction using CT, 18F-FDG PET/MRI and CA 19-9

BACKGROUND

CT prediction of resectability and prognosis following neoadjuvant treatment (NAT) in patients with pancreatic ductal adenocarcinoma (PDAC) remains challenging. This study aims to determine whether addition of ¹⁸F-fluorodeoxyglucose (FDG) postiron emission tomography (PET)/MRI and carbohydrate antigen (CA) 19-9 to contrast-enhanced CT (CECT) can improve accuracy of predicting resectability compared to CECT alone and predict prognosis in PDAC patients after NAT.

METHODS

In this retrospective study, 120 PDAC patients (65 women; mean age, 66.7 years [standard deviation, 8.4]) underwent CECT, PET/MRI, and CA 19-9 examinations after NAT between January 2013 and June 2021. Three board-certified radiologists independently rated the overall resectability on a 5-point scale (score 5, definitely resectable) in three sessions (session 1, CECT; 2, CECT plus PET/MRI─no FDG avidity and no diffusion restriction at tumor-vessel contact indicated modification of CECT scores to ≥ 3; 3, CECT plus PET plus CA 19-9─no FDG avidity at tumor-vessel contact and normalized CA 19-9 indicated modification of CECT scores to ≥ 3). Jackknife free-response receiver operating characteristic method and generalized estimating equations were used to compare pooled area under the curve (AUC), sensitivity, and specificity of three sessions. Predictors for recurrence-free survival (RFS) were assessed using Cox regression analyses.

RESULTS

Each session showed different pooled AUC (session 1 vs. 2 vs. 3, 0.853 vs. 0.873 vs. 0.874, p = 0.026), sensitivity (66.2% [137/207] vs. 86.0% [178/207] vs. 84.5% [175/207], p < 0.001) and specificity (67.3% [103/153] vs. 58.8% [90/153] vs. 60.1% [92/153], p = 0.048). According to pairwise comparison, specificity of CECT plus PET/MRI was lower than that of CECT alone (adjusted p = 0.042), while there was no significant difference in specificity between CECT alone and CECT plus PET plus CA 19-9 (adjusted p = 0.081). Twenty-eight of 69 patients (40.6%) with R0 resection experienced tumor recurrence (mean follow-up, 18.0 months). FDG avidity at tumor-vessel contact on post-NAT PET (HR = 4.37, p = 0.033) and pathologically confirmed vascular invasion (HR = 5.36, p = 0.004) predicted RFS.

CONCLUSION

Combination of CECT, PET and CA 19-9 increased area under the curve and sensitivity for determining resectability, compared to CECT alone, without compromising the specificity. Furthermore, ¹⁸F-FDG avidity at tumor-vessel contact on post-NAT PET predicted RFS.

Change Impact of Body Composition During Neoadjuvant Chemoradiotherapy in Patients with Resectable and Borderline Resectable Pancreatic Ductal Adenocarcinoma Undergoing Pancreatectomy

BACKGROUND

The change impact of body composition during neoadjuvant therapy on clinical outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) remains unclear. The aim of this study was to investigate the association between changes in body composition during neoadjuvant chemoradiotherapy (NACRT) and postoperative outcomes in patients with PDAC undergoing pancreatectomy, using three-dimensional images.

METHODS

We reviewed 66 consecutive patients with resectable/borderline resectable PDAC receiving gemcitabine and S-1 with radiotherapy between April 2010 and June 2016. Body compositions were evaluated pre- and post-NACRT. All patients were hospitalized and supplied with regulated diet during NACRT treatment.

RESULTS

Psoas major muscle volume index (PMI), abdominal fat volume index, and visceral fat volume index decreased significantly after NACRT (P < 0.0001, P < 0.0001, P < 0.0001, respectively). The post-NACRT CA19-9 level decreased significantly in the small-PMI-decrease group compared with the large-PMI-decrease group (P = 0.046). Recurrence-free survival (RFS) and overall survival (OS) of the large-PMI-decrease group were significantly poorer than those of the small-PMI-decrease group (P = 0.002, P = 0.006, respectively). On the other hand, there were no significant differences in RFS and OS between groups with high and low PMI, at the point of either pre-NACRT (P = 0.117, P = 0.123, respectively) or post-NACRT (P = 0.065, P = 0.064, respectively). Multivariate analysis identified a large percentage decrease in PMI as an independent risk factor for recurrence and death (P = 0.003, P = 0.002, respectively).

CONCLUSIONS

Loss of skeletal muscle mass during NACRT was an independent risk factor for survival in patients with PDAC.

Clinical Implications of FDG-PET in Pancreatic Ductal Adenocarcinoma Patients Treated with Neoadjuvant Therapy

PURPOSE

To evaluate the clinical significance of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with pancreatic ductal adenocarcinoma who underwent neoadjuvant therapy.

METHODS

Among 285 consecutive patients who underwent pancreatic resection for pancreatic ductal adenocarcinoma between 2015 and 2021, 86 who underwent preoperative ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography after completion of neoadjuvant treatment were reviewed. Among preoperative factors, including post-treatment maximum standardized uptake value, predictors of early recurrence and poor prognosis were identified using multivariate analysis for decision making in surgery.

RESULTS

Nineteen (22%) patients with pancreatic ductal adenocarcinoma demonstrated high maximum standardized uptake (≥ 4.5). High post-treatment maximum standardized uptake (≥ 4.5) predicted early recurrence within 6 months after surgery and correlated with shorter recurrence-free survival. Elevated post-treatment CA19-9 level (> 37 U/ml) and maximum standardized uptake ≥ 4.5 were independent prognostic factors. Post-treatment, a high maximum standardized uptake value indicated a poorer prognosis than a low maximum standardized uptake value in both patients with elevated CA19-9 and normal CA19-9 levels. The median overall survival in patients with elevated post-treatment CA19-9 and high maximum standardized uptake was only 17 months; 67% experienced early recurrence. Dynamic changes in maximum standardized uptake during neoadjuvant therapy were correlated with pathological response to neoadjuvant therapy, but not with radiological response or change in CA19-9 level.

CONCLUSIONS

Post-treatment assessment using maximum standardized uptake value is useful for stratifying patients with pancreatic ductal adenocarcinoma who will benefit from surgery. Instead of subsequent curative resection, additional neoadjuvant therapy should be considered in patients with a persistently high maximum standardized uptake value.

Defining the Optimal Duration of Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Time for a Personalized Approach?

ABSTRACT

Despite recent advances, pancreatic ductal adenocarcinoma (PDAC) continues to be associated with dismal outcomes, with a cure evading most patients. While historic treatment for PDAC has been surgical resection followed by 6 months of adjuvant therapy, there has been a recent shift toward neoadjuvant treatment (NAT). Several considerations support this approach, including the characteristic early systemic spread of PDAC, and the morbidity often surrounding pancreatic resection, which can delay recovery and preclude patients from starting adjuvant treatment. The addition of NAT has been suggested to improve margin-negative resection rates, decrease lymph node positivity, and potentially translate to improved survival. Conversely, complications and disease progression can occur during preoperative treatment, potentially eliminating the chance of curative resection. As NAT utilization has increased, treatment durations have been found to vary widely between institutions with an optimal duration remaining undefined. In this review, we assess the existing literature on NAT for PDAC, reviewing treatment durations reported across retrospective case series and prospective clinical trials to establish currently used approaches and seek the optimal duration. We also analyze markers of treatment response and review the potential for personalized approaches that may help clarify this important treatment question and move NAT toward a more standardized approach.