Prognostic value of preoperative fluorodeoxyglucose positron emission tomography/computed tomography in patients with potentially resectable pancreatic cancer

Preoperative carbohydrate antigen 19-9 and standard uptake value of positron emission tomography-computed tomography as prognostic markers in patients with pancreatic ductal adenocarcinoma

BACKGROUND

Among various prognostic factors of pancreatic cancer, preoperative clinical information is obtained by imaging modality. This study aimed to evaluate clinical usefulness of preoperative carbohydrate antigen and preoperative standard uptake value in 18F-fluorodeoxyglucose positron emission tomography as predictive biological markers for resectable pancreatic ductal adenocarcinoma.

METHODS

A total of 189 patients with PDAC who underwent preoperative PET-computed tomography were evaluated. Patients underwent neoadjuvant chemotherapy, and R2 resection was excluded. The correlation between SUVmax and clinicopathologic parameters was analyzed. The C-tree statistical method was used to estimate cutoff values of logCA19-9 and SUVmax for survival rate. A multivariate analysis was conducted to identify prognostic factors for overall survival.

RESULTS

The median duration of OS was 26 months, and the 5-year survival rate was 22.4%. The optimal cutoff values for CA19-9 level was 150 U/mL and SUVmax was 5.5. When subjects were divided into three groups according to the combination of CA19-9 level and SUVmax from C-tree (high-risk group, CA19-9 > 150 U/mL and SUVmax > 5.5; intermediate-risk group, CA19-9 ≤ 150 U/mL and SUVmax > 5.5 or CA19-9 > 150 U/mL and SUVmax ≤ 5.5; and low-risk group, CA19-9 ≤ 150 U/mL and SUVmax ≤ 5.5), there was a significant 5YSR difference (5.6%, 24.3%, and 36.5%, P < .001). The multivariate analysis revealed high SUVmax, high preoperative CA19-9 level, venous invasion, and adjuvant chemotherapy were prognostic factors of OS.

CONCLUSIONS

CA19-9 and SUVmax are strong prognostic biological factors in resectable PDAC. Moreover, patients with high CA19-9 level and SUVmax are not indicated for upfront surgery.

Prediction of pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography

AIM

To determine whether the pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma (PDAC) can be predicted using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (F-18 FDG-PET).

MATERIALS AND METHODS

Twenty-eight patients with PDAC who underwent only neoadjuvant chemotherapy (NAC) before surgery were enrolled in the study. All patients had F-18 FDG-PET examinations before NAC. The resected specimen was pathologically evaluated according to the Classification of Pancreatic Carcinoma (7th edn). Patients were categorised into a non-response group and a response group based on the pathological findings. The non-response group (Grades 1a and 1b) showed ≤50% necrosis in the specimen, while the specimens of the response group (Grades 2-3) showed >50% necrosis. The maximum standardised uptake values (SUVmax) of the tumours on F-18 FDG-PET were measured. The mean values of SUVmax were compared between the two groups. The diagnostic performance of SUVmax in distinguishing the two groups was also evaluated using receiver operating characteristic analysis.

RESULTS

The mean SUVmax of the response group was higher than that of the non-response group (9.00 ± 1.78 versus 4.26 ± 2.35; p<0.001). The optimal cut-off value of SUVmax was 9.28 for distinguishing the two groups. The sensitivity, specificity, and accuracy for the prediction in the response group were 80%, 95.7%, and 92.9%, respectively.

CONCLUSIONS

SUVmax on F-18 FDG-PET may be useful as a biomarker to predict the pathological response to NAC in patients with PDAC.

Nab-paclitaxel plus S-1 with or without PD-1 inhibitor in pancreatic ductal adenocarcinoma with only hepatic metastases: a retrospective cohort study

PURPOSE

The evidence regarding programmed cell death 1 (PD-1) inhibitors on pancreatic ductal adenocarcinoma (PDAC) with metastases remains controversial. This study aimed to assess the efficacy and safety of Nab-paclitaxel plus S1 (NPS) with or without Sintilimab, a PD-1 inhibitor, in patients with PDAC with only hepatic metastases (mPDAC).

METHODS

Untreated mPDAC patients who received NPS with (the combination group) or without Sintilimab (the NPS group) were retrospectively studied. Surgery was considered when the pancreatic tumor became resectable or borderline resectable on radiological examinations, and with complete metabolic response of liver metastases.

RESULTS

Between October 2017 and February 2020, 32 patients were in the combination group and 34 patients in the NPS group. Successful salvage resection was achieved in 17 (25.8%) patients after tumor-downstaging (combination 12 vs. NPS 5, P = 0.03). The median overall survival (OS) was 16.8 months in the combination group and 10.0 months in the NPS group (P = 0.002). Remarkable OS benefit was observed in patients with decline in CA19-9 of ≥ 50% (16.0 vs. 6.5, P = 0.003), reduction in ¹⁸F-fluorodeoxyglucose uptake of primary tumor of ≥ 50% (16.5 vs. 10.0, P < 0. 001) and after salvage resection (20.1 vs. 11.0, P < 0. 001). No significant difference in Grade 3 or higher adverse events were seen between the two groups (40.6% vs. 32.4%, P = 0.49).

CONCLUSIONS

Despite the inherent biases of this retrospective study, the addition of Sintilimab significantly improved salvage resection rates and OS compared with the NPS regimen and had a favorable safety profile in treatment naïve mPDAC patients.

The diagnostic value of 18F-FDG PET/CT in identifying the causes of fever of unknown origin

BACKGROUND

This study investigated the clinical significance of ¹⁸F-fluorodeoxyglucose positron emission tomography / computed tomography (¹⁸F-FDG PET/CT) in identifying the causes of fever of unknown origin (FUO).

METHODS

Patients with a fever who received an ¹⁸F-FDG PET/CT examination were retrospectively selected. The means of the two groups were compared using an independent-samples t-test.

RESULTS

Among the 89 included patients, 66 were diagnosed using ¹⁸F-FDG PET/CT. The sensitivity, specificity and diagnostic accuracy of ¹⁸F-FDG PET/CT for the diagnosis of patients with FUO were 84.5%, 25.8%, and 64.0%, respectively. The detection rates of ¹⁸F-FDG PET/CT for neoplastic diseases, infectious diseases and non-infectious inflammatory diseases were 100%, 61.3%, and 75%, respectively. The difference in C-reactive protein (CRP) levels between the two groups was statistically significant.

CONCLUSIONS

¹⁸F-FDG PET/CT has great clinical importance in diagnosing and identifying causes of FUO and improves the accuracy of FUO diagnosis when combined with serum CRP levels.

The Utility of PET/Computed Tomography for Radiation Oncology Planning, Surveillance, and Prognosis Prediction of Gastrointestinal Tumors

At present, the strongest evidence for the use of PET/computed tomography (CT) in gastrointestinal (GI) malignancies is to rule out distant metastatic disease at diagnosis, radiation treatment planning for anal malignancies, and disease recurrence monitoring in colorectal and anal malignancies. Use of PET/CT for GI malignancies continues to evolve over time, with new studies evaluating prognostic abilities of PET/CT and with increasing sensitivity and spatial resolution of more modern PET/CT scanners. The authors encourage future applications and prospective evaluation of the use of PET/CT in the staging, prognostication, and recurrence prediction for GI malignancies.

18F-Fluorodeoxyglucose Positron Emission Tomography Predicts Treatment Efficacy and Clinical Outcome for Patients With Pancreatic Carcinoma: A Meta-analysis

OBJECTIVES

F-Fluorodeoxyglucose positron emission tomography (FDG-PET) has been an important modality for detecting malignancies. Recently, an increasing number of studies reported the utility of FDG-PET parameters in predicting clinical outcomes and treatment assessment in variety of cancers. We aimed at clarifying both the prognostic role and assessment value of FDG-PET in pancreatic carcinoma.

METHODS

We systematically searched electronic databases of PubMed, Embase, Cochrane Library, and Web of Science to identify relevant studies to conduct this meta-analysis. Comparative analyses of the pooled hazard ratio (HR) for overall survival were performed to assess the utility of FDG-PET parameters in prognosis evaluation and treatment assessment by random-effect model.

RESULTS

Twenty-three studies with 1762 patients met the inclusion criteria of this meta-analysis. The pooled results revealed that greater maximum standardized uptake value of the primary tumor was significantly correlated with poorer overall survival (HR, 1.31; 95% confidence interval, 1.15-1.50; P < 0.001). Besides, greater reduction of maximum standardized uptake value after treatments indicated significant better overall survival (HR, 0.68; 95% confidence interval, 0.47-0.98; P = 0.037).

CONCLUSIONS

F-Fluorodeoxyglucose positron emission tomography parameters might be helpful not only for predicting survival outcome but also for selecting potentially efficacious treatments in patients with pancreatic carcinoma.