Prognostic value of 18FDG PET/CT volumetric parameters in the survival prediction of patients with pancreatic cancer

Value of [18F]AlF-NOTA-FAPI-04 PET/CT for predicting pathological response and survival in patients with locally advanced pancreatic ductal adenocarcinoma receiving neoadjuvant chemotherapy

OBJECTIVES

This study aimed to evaluate the predictive value of [18F]AlF-NOTA-FAPI-04 PET/CT for pathological response to neoadjuvant chemotherapy (NCT) and prognosis in patients with locally advanced pancreatic ductal adenocarcinoma (LAPDAC).

METHODS

This study included 34 patients with histopathologically and radiologically confirmed LAPDAC who received [18F]AlF-NOTA-FAPI-04 PET/CT scans before NCT. After 4-6 cycles of NCT, these patients underwent radical resection. Pathological response to NCT was assessed by pathological tumor regression grades (TRG) based on the Evans system. PET/CT parameters were evaluated for their association with TRG, recurrence-free survival (RFS) and overall survival (OS) after NCT, including the maximum standardized uptake value (SUVmax), FAPI-avid tumor volume (FTV), total lesion FAP expression (TLF) of primary tumor, total FAPI-avid pancreatic volume (FPV) and total pancreatic FAP expression (TPF) of total pancreas.

RESULTS

Of 34 patients with LAPDAC, 14 patients had a pathologic good response (PGR, Evans III-IV), and 20 patients had a pathologic poor response (PPR, Evans I-II). Both the primary tumor SUVmax, FTV and TLF, and total pancreas FPV and TPF in the PGR groups were significantly lower than those in the PPR groups. Furthermore, SUVmax and TLF were higher in poorly differentiated LAPDAC than in well-moderately differentiated neoplasms. The FTV, TLF, FPV and TPF were closely associated with RFS and OS. On multivariate analysis, patients with FTV > 54.21 and TLF > 290.21 had a worse RFS and OS, respectively (HR = 3.24, P = 0.014 and HR = 3.35, P = 0.019) and OS (HR = 7.35, P = 0.002 and HR = 7.09, P = 0.004) in LAPDAC after NCT.

CONCLUSIONS

The parameters of [18F]AlF-NOTA-FAPI-04 PET/CT had the excellent performance for predicting pathologic TRG after NCT in LAPDAC. FTV and TLF were independent postoperative prognostic factors for RFS and OS for LAPDAC.

Total lesion glycolysis is a promising predictor of chemo-response in pancreatic cancer patients treated with neoadjuvant chemotherapy prior to surgery

BACKGROUND

There has been increased use of neoadjuvant chemotherapy (NAC) in resectable pancreatic ductal adenocarcinoma (PDAC) patients. [18F]fluoro-2-deoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) scan is being frequently used to determine treatment response in PDAC patients undergoing NAC. Maximum standardized uptake value (SUVmax) is conventionally used as an FDG-PET/CT parameter, but there are emerging parameters, such as total lesion glycolysis (TLG), which take into account mean standardized uptake (SUVmean) and metabolic tumour volume (MTV). This study compared the ability of emerging FDG-PET/CT parameters (i.e. SUVmean, MTV and TLG) to predict chemo-response compared to SUVmax.

METHODS

In this single centre, retrospective study, NAC-treated PDAC patients (n = 74) for whom both pre- and post-NAC FDG-PET/CT scans were available were recruited. All scans were imported to a single analysis platform and reanalysed. Chemo-response was determined by the assessment of percentage viable tumour cells in the tumour bed. Statistical analysis was performed on the data.

RESULTS

A significant correlation was observed between post-treatment FDG-PET/CT scan parameters and viable cancer cells in the tumour bed, with TLG showing a higher degree of correlation (r = .3131) compared to all other parameters (r = .2722-.3008). The percentage decrease in the TLG (post-NAC scan vs. pre-NAC scan) demonstrated the highest degree of correlation with viable cancer cells in the tumour bed (r = -.3444) and had a statistically significant (p = .0157) effect between NAC responders (Median = 80.57) and non-responders (Median = 65.16). The difference between TLG (post-NAC scan vs. pre-NAC scan) was shown to be an independent prognostic indicator for overall survival (hazard ratio = .5033, p = .0361).

CONCLUSION

TLG was shown to be a superior predictor of chemo-response and patient prognosis compared to all other FDG-PET/CT parameters in PDAC patients treated with NAC.

Updates in the Role of Positron Emission Tomography/Computed Tomography in Radiation Oncology in Gastrointestinal Malignancies

Positron Emission Tomography/Computed Tomography (PET/CT) plays a critical role in managing gastrointestinal (GI) cancers within radiation oncology. It enhances tumor detection, staging, and lymph node involvement assessment, leading to better-targeted radiation treatment. PET/CT also aids in delineating tumor volumes to minimize geographic misses, enabling precise dose escalation to metabolically active regions. Despite its benefits, PET/CT has limitations such as false positives and dependency on complementary imaging. Emerging technologies offer real-time adjustments and personalized treatments, advancing precision medicine in GI radiation oncology. Further research is needed to refine PET/CT integration for improved treatment outcomes and cost-effectiveness.

Evaluating the role of sarcopenia and [18F]FDG PET/CT parameters in prognosis of pancreatic ductal adenocarcinoma

This study investigates the relationship between 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) metabolic parameters, clinicopathological characteristics, and sarcopenia in patients with pancreatic ductal adenocarcinoma (PDAC) and evaluates their prognostic roles.

MATERIAL AND METHODS

The primary tumor's maximum standard uptake (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) values, as well as clinicopathological factors, were evaluated retrospectively. Computed tomography (CT) was used to assess the skeletal muscle index (SMI). Sarcopenia was defined based on SMI calculated at the third lumbar vertebra (L3). SMI cut-off values ​​for sarcopenia were accepted as 44.77 cm2/m2 for men and 32.50 cm2/m2 for women. The primary endpoint was the overall survival (OS). OS data were analyzed by the Kaplan-Meier method and compared using the log-rank test. To identify predictive factors for sarcopenia, multivariable logistic regression was used following univariable logistic regression. Cox proportional hazards regression analyses were used to find predictors of OS.

RESULTS

Of the 86 patients included in the study, 37 (43%) were diagnosed with sarcopenia. Compared with non-sarcopenic patients, sarcopenia was observed in older patients (P=0,028) and patients with lower body mass index (BMI) (p=0,001). Age and BMI independently predicted sarcopenia. Univariate analysis identified sarcopenia, advanced stage, and higher primary tumor TLG as significant predictors of overall survival. Multivariate Cox regression analysis revealed that the advanced tumor stage (p=0.017) and higher TLG (p=0,042) independently predicted OS. The median OS was 9.4 months in non-sarcopenic patients and 5.0 months in sarcopenic patients (p=0,021).

CONCLUSION

In this study cohort, advanced-stage disease and higher primary tumor TLG were identified as independent predictors of OS in patients with PDAC. Additionally, we emphasize the importance of incorporating [18F]FDG PET/CT-derived sarcopenia assessments into the prognostic evaluation and clinical management of PDAC patients. While sarcopenia was associated with shorter OS in univariate analysis, it was not an independent predictor in multivariate analysis.

Histology-Based Radiomics for [18F]FDG PET Identifies Tissue Heterogeneity in Pancreatic Cancer

Radiomics features can reveal hidden patterns in a tumor but usually lack an underlying biologic rationale. In this work, we aimed to investigate whether there is a correlation between radiomics features extracted from [18F]FDG PET images and histologic expression patterns of a glycolytic marker, monocarboxylate transporter-4 (MCT4), in pancreatic cancer. Methods: A cohort of pancreatic ductal adenocarcinoma patients (n = 29) for whom both tumor cross sections and [18F]FDG PET/CT scans were available was used to develop an [18F]FDG PET radiomics signature. By using immunohistochemistry for MCT4, we computed density maps of MCT4 expression and extracted pathomics features. Cluster analysis identified 2 subgroups with distinct MCT4 expression patterns. From corresponding [18F]FDG PET scans, radiomics features that associate with the predefined MCT4 subgroups were identified. Results: Complex heat map visualization showed that the MCT4-high/heterogeneous subgroup was correlating with a higher MCT4 expression level and local variation. This pattern linked to a specific [18F]FDG PET signature, characterized by a higher SUVmean and SUVmax and second-order radiomics features, correlating with local variation. This MCT4-based [18F]FDG PET signature of 7 radiomics features demonstrated prognostic value in an independent cohort of pancreatic cancer patients (n = 71) and identified patients with worse survival. Conclusion: Our cross-modal pipeline allows the development of PET scan signatures based on immunohistochemical analysis of markers of a particular biologic feature, here demonstrated on pancreatic cancer using intratumoral MCT4 expression levels to select [18F]FDG PET radiomics features. This study demonstrated the potential of radiomics scores to noninvasively capture intratumoral marker heterogeneity and identify a subset of pancreatic ductal adenocarcinoma patients with a poor prognosis.

Preoperative CA19‑9 level and dual time point FDG‑PET/CT as strong biological indicators of borderline resectability in pancreatic cancer: A retrospective study

Tumor resectability, which is increasingly determined based on preoperative chemotherapy, is critical in determining the best treatment for pancreatic cancers. The present study evaluated the usefulness of serum carbohydrate antigen 19-9 (CA19-9) and the preoperative 8F-fluorodeoxyglucose positron emission tomography/computed tomography standardized uptake value (SUV) percentage change (SUVmax%=[(SUVmax2-SUVmax1)/SUVmax1] ×100, where SUVmax1 and SUVmax2 represent the initial and delayed phases, respectively) as biological factors indicative of tumor resectability. The present study included patients with resectable pancreatic cancer who underwent complete surgical resection, for whom both CA19-9 and SUVmax% were documented using cut-off values of 500 U/ml and 24.25%, respectively. Patients were classified as follows: i) High CA19-9 and SUVmax%: both CA19-9 and SUVmax% were elevated; ii) high CA19-9 or SUVmax%: either CA19-9 or SUVmax% were elevated; or iii) low CA19-9 and SUVmax%: neither value met the cut-off. Relapse-free survival (RFS) and overall survival (OS) were calculated, for which univariate and multivariate analyses were performed. Of the 86 patients included, 39 were classified as high CA19-9 or SUVmax% and 12 as high CA19-9 and SUVmax%, with the former group having a significantly worse RFS (vs. low CA19-9 and SUVmax%; P<0.001; vs. high CA19-9 or SUVmax%; P=0.011) and OS (vs. low CA19-9 and SUVmax%, P=0.002; vs. high CA19-9 or SUVmax%, P<0.001). Therefore, high CA19-9 and SUVmax% was an independent predictor of worse RFS (P<0.001) and OS (P=0.003). In conclusion, CA19-9 and SUVmax% can be utilized as biological indicators of resectability.

Quarter-Century PET/Computed Tomography Transformation of Oncology: Hepatobiliary and Pancreatic Cancer

[18F] Fluorodeoxyglucose (18F-FDG) PET/CT can improve the staging accuracy and clinical management of patients with hepatobiliary and pancreatic cancers, by detection of unsuspected metastases. 18F-FDG PET/CT metabolic parameters are valuable in predicting treatment response and survival. Metabolic response on 18F-FDG PET/CT can predict preoperative pathologic response to neoadjuvant therapy in patients with pancreatic cancer and determine prognosis. Several novel non-FDG tracers, such as 68Ga prostate-specific membrane antigen (PSMA) and 68Ga-fibroblast activation protein inhibitor (FAPI) PET/CT, show promise for imaging hepatobiliary and pancreatic cancers with potential for radioligand therapy.

The Impact of Metabolic 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Parameters on the Prognosis of Resectable Pancreatic Adenocarcinoma

Objectives

¹⁸F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) is a useful staging method in pancreatic cancer. The prognosis of pancreatic adenocarcinoma is affected by the tumor stage and resectable state. Maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of primary tumors are related to prognostic parameters in pancreatic cancer. This study compared ¹⁸F-FDG PET/CT findings with prognostic factors and overall survival of patients with pancreatic cancer.

Methods

Patients with pancreatic adenocarcinoma, referred to our department between 2015 and 2022 for staging, were retrospectively evaluated. Head-to mid-thigh PET/CT images were obtained 1 h after ¹⁸F-FDG injection. Demographic data, survival, and clinical and pathological findings of 39 patients, who underwent surgery after PET/CT imaging, were collected. All primary tumor MTV, SUV_max, background SUV_max, and TLG data have were measured.

Results

The images of 39 patients (24 women and 15 men) with a mean age of 66.62±9.60 years were evaluated. The mean SUV_max, MTV 40%, and TLG of the primary tumors in the pancreatic tissue were 6.28±2.33, 19.33±9.77, and 66.56±45.99, respectively. The average survival after disease diagnosis was 18.97±11.47 (2-55) months. MTV and TLG were significantly higher in patients who died during our study. SUV_max has a significant effect on mortality.

Conclusion

¹⁸F-FDG PET/CT metabolic parameters of SUV_max, MTV, and TLG could help predicting the prognosis of pancreatic cancer preoperatively and follow-up in patients with resectable tumors. Additionally, in our study group tumor grade and perineural invasion significantly affected overall survival.

Artificial Intelligence Algorithm-Based Computerized Tomography Image Features Combined with Serum Tumor Markers for Diagnosis of Pancreatic Cancer

The objective of this study was to analyze the value of artificial intelligence algorithm-based computerized tomography (CT) image combined with serum tumor markers for diagnoses of pancreatic cancer. In the study, 68 hospitalized patients with pancreatic cancer were selected as the experimental group, and 68 hospitalized patients with chronic pancreatitis were selected as the control group, all underwent CT imaging. An image segmentation algorithm on account of two-dimensional (2D)-three-dimensional (3D) convolution neural network (CNN) was proposed. It also introduced full convolutional network (FCN) and UNet network algorithm. The diagnostic performance of CT, serum carbohydrate antigen-50 (CA-50), serum carbohydrate antigen-199 (CA-199), serum carbohydrate antigen-242 (CA-242), combined detection of tumor markers, and CT-combined tumor marker testing (CT-STUM) for pancreatic cancer were compared and analyzed. The results showed that the average Dice coefficient of 2D-3D training was 84.27%, which was higher than that of 2D and 3D CNNs. During the test, the maximum and average Dice coefficient of the 2D-3D CNN algorithm was 90.75% and 84.32%, respectively, which were higher than the other two algorithms, and the differences were statistically significant (P < 0.05). The penetration ratio of pancreatic duct in the experimental group was lower than that in the control group, the rest were higher than that in the control group, and the differences were statistically significant (P < 0.05). CA-50, CA-199, and CA-242 in the experimental group were 141.72 U/mL, 1548.24 U/mL, and 83.65 U/mL, respectively, which were higher than those in the control group, and the differences were statistically significant (P < 0.05). The sensitivity, specificity, positive predictive value, and authenticity of combined detection of serum tumor markers were higher than those of CA-50, CA-199, and CA-242, and the differences were statistically significant (P < 0.05). The results showed that the proposed algorithm 2D-3D CNN had good stability and image segmentation performance. CT-STUM had high sensitivity and specificity in diagnoses of pancreatic cancer.

Prognostic Value of Volume-Based Parameters Measured by SSTR PET/CT in Neuroendocrine Tumors: A Systematic Review and Meta-Analysis

Purpose: A meta-analysis was conducted to investigate the value of the volume parameters based on somatostatin receptor (SSTR)-positron emission tomography (PET) in predicting the prognosis in patients with neuroendocrine tumors (NETs). Material: PUBMED, EMBASE, Cochrane library, and Web of Knowledge were searched from January 1990 to May 2021 for studies evaluating prognostic value of volume-based parameters of SSTR PET/CT in NETs. The terms used were "volume," "positron emission tomography," "neuroendocrine tumors," and "somatostatin receptor." Pooled hazard ratio (HR) values were calculated to assess the correlations between volumetric parameters, including total tumor volume (TTV) and total-lesion SSTR expression (TL-SSTR), with progression-free survival (PFS) and overall survival (OS). Heterogeneity and subgroup analysis were performed. Funnel plots, Begg's and Egger's test were used to assess possible underlying publication bias. Results: Eight eligible studies involving 593 patients were included in the meta-analysis. In TTV, the pooled HRs of its prognostic value of PFS and OS were 2.24 (95% CI: 1.73-2.89; P < 0.00001) and 3.54 (95% CI, 1.77-7.09; P = 0.0004), respectively. In TL-SSTR, the pooled HR of the predictive value was 1.61 (95% CI, 0.48-5.44, P = 0.44) for PFS. Conclusion: High TTV was associated with a worse prognosis for PFS and OS in with patients NETs. The TTV of SSTR PET is a potential objective prognosis predictor.

Metastatic pancreatic cancer: Mechanisms and detection (Review)

Pancreatic cancer (PC) is a lethal malignancy. Its prevalence rate remains low but continues to grow each year. Among all stages of PC, metastatic PC is defined as late-stage (stage IV) PC and has an even higher fatality rate. Patients with PC do not have any specific clinical manifestations. Most cases are inoperable at the time-point of diagnosis. Prognosis is also poor even with curative-intent surgery. Complications during surgery, postoperative pancreatic fistula and recurrence with metastatic foci make the management of metastatic PC difficult. While extensive efforts were made to improve survival outcomes, further elucidation of the molecular mechanisms of metastasis poses a formidable challenge. The present review provided an overview of the mechanisms of metastatic PC, summarizing currently known signaling pathways (e.g. epithelial-mesenchymal transition, NF-κB and KRAS), imaging that may be utilized for early detection and biomarkers (e.g. carbohydrate antigen 19-9, prostate cancer-associated transcript-1, F-box/LRR-repeat protein 7 and tumor stroma), giving insight into promising therapeutic targets.

Clinical Impact of 18F-FDG PET/CT in the Diagnostic Workup of Pancreatic Ductal Adenocarcinoma: A Systematic Review

In this review, the performance of fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in the diagnostic workup of pancreatic ductal adenocarcinoma (PDAC) is evaluated. A comprehensive literature search up to September 2020 was performed, selecting studies with the presence of: sample size ≥10 patients and index test (i.e., “FDG” or “18F-FDG” AND “pancreatic adenocarcinoma” or “pancreas cancer” AND “PET” or “positron emission tomography”). The methodological quality was evaluated using the revised quality assessment of diagnostic accuracy studies (QUADAS-2) tool and presented according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Basic data (authors, year of publication, country and study design), patients’ characteristics (number of enrolled subjects and age), disease phase, type of treatment and grading were retrieved. Forty-six articles met the adopted research criteria. The articles were divided according to the considered clinical context. Namely, besides conventional anatomical imaging, such as computed tomography (CT) and magnetic resonance imaging (MRI), molecular imaging with FDG PET/CT is an important tool in PDAC, for all disease stages. Further prospective studies will be necessary to confirm the cost-effectiveness of such imaging techniques by testing its real potential improvement in the clinical management of PDAC.