Preoperative FDG-PET predicts early recurrence and a poor prognosis after resection of pancreatic adenocarcinoma

Qualitative flow metabolic phenotype of pancreatic cancer. A new prognostic biomarker?

BACKGROUND

Retrospective analysis to investigate the relationship between the flow-metabolic phenotype and overall survival (OS) of pancreatic ductal adenocarcinoma (PDAC) and its potential clinical utility.

METHODS

Patients with histopathologically proven PDAC between 2005 and 2014 using tumor attenuation on routine pre-operative CECT as a surrogate for the vascularity and [18F]FDG-uptake as a surrogate for metabolic activity on [18F]FDG-PET.

RESULTS

In total, 93 patients (50 male, 43 female, median age 63) were included. Hypoattenuating PDAC with high [18F]FDG-uptake has the poorest prognosis (median OS 7 ± 1 months), compared to hypoattenuating PDAC with low [18F]FDG-uptake (median OS 11 ± 3 months; p = 0.176), iso- or hyperattenuating PDAC with high [18F]FDG-uptake (median OS 15 ± 5 months; p = 0.004) and iso- or hyperattenuating PDAC with low [18F]FDG-uptake (median OS 23 ± 4 months; p = 0.035). In multivariate analysis, surgery combined with tumor differentiation, tumor stage, systemic therapy and flow metabolic phenotype remained independent predictors for overall survival.

DISCUSSION

The novel qualitative flow-metabolic phenotype of PDAC using a combination of CECT and [18F]FDG-PET features, predicted significantly worse survival for hypoattenuating-high uptake pancreatic cancers compared to the other phenotypes.

Oncogenic KRAS triggers metabolic reprogramming in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with an extremely high lethality rate. Oncogenic KRAS activation has been proven to be a key driver of PDAC initiation and progression. There is increasing evidence that PDAC cells undergo extensive metabolic reprogramming to adapt to their extreme energy and biomass demands. Cell-intrinsic factors, such as KRAS mutations, are able to trigger metabolic rewriting. Here, we update recent advances in KRAS-driven metabolic reprogramming and the associated metabolic therapeutic potential in PDAC.

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.

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.

Advancements of molecular imaging and radiomics in pancreatic carcinoma

Despite the recent progress of medical technology in the diagnosis and treatment of tumors, pancreatic carcinoma remains one of the most malignant tumors, with extremely poor prognosis partly due to the difficulty in early and accurate imaging evaluation. This paper focuses on the research progress of magnetic resonance imaging, nuclear medicine molecular imaging and radiomics in the diagnosis of pancreatic carcinoma. We also briefly described the achievements of our team in this field, to facilitate future research and explore new technologies to optimize diagnosis of pancreatic carcinoma.

Prognostic value of preoperative [68 Ga]Ga-FAPI-04 PET/CT in patients with resectable pancreatic ductal adenocarcinoma in correlation with immunohistological characteristics

PURPOSE

Our aim was to assess the prognostic value of [⁶⁸ Ga]Ga-FAPI-04 positron emission tomography (PET) uptake in PDAC and to evaluate the correlation between in vivo lesional radioactivity with pathological characteristics of pancreatic ductal adenocarcinoma (PDAC).

METHODS

We retrospectively analyzed treatment-naïve PDAC patients who underwent preoperative [⁶⁸ Ga]Ga-FAPI-04 PET/CT followed by pancreatectomy. The tracer uptake was determined as maximum tumor standardized uptake value (SUV_max), FAPI-avid tumor volume (FTV), total lesion FAP expression (TLF) as well total pancreatic uptake (TSUV_max), total FAPI-avid pancreatic volume (FPV), and total pancreatic FAP expression (TPF). Spearman's correlation analysis was performed to evaluate the association between [⁶⁸ Ga]Ga-FAPI-04 PET/CT imaging and ex vivo immunohistological FAP expression and pathological characteristics of surgical specimens (differentiation, size, vascularity, perineural invasion, and lymph node metastases). Kaplan-Meier and hazard ratio (HR, log-rank) methods were used to evaluate the prognostic value of [⁶⁸ Ga]Ga-FAPI-04 PET/CT and clinicopathological factors.

RESULTS

Thirty-seven surgical PDAC patients were included. The ex vivo expression of FAP was significantly associated with the tumor SUV_max and TLF. FAP expression was more abundant in poorly differentiated PDAC than in well- to moderately differentiated neoplasms. Tumor SUV_max or TLF and pancreatic TSUV_max or TPF were significantly correlated with tumor size, differentiation, and perineural invasion, respectively. SUV_max had a significant independent prognostic value for recurrence-free survival (HR = 2.46, P < 0.05), while [⁶⁸ Ga]Ga-FAPI-04 TPF predicted overall survival (HR = 12.82, P < 0.05).

CONCLUSION

The in vivo [⁶⁸ Ga]Ga-FAPI-04 uptake in localized PDAC showed a significant correlation with ex vivo FAP expression and aggressive pathological characteristics. [⁶⁸ Ga]Ga-FAPI-04 PET/CT also presented a potential for postoperative prognostication of PDAC. Elevated fibroblast activity induced by obstructive pancreatitis might be associated with the patient's survival.

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.

Impact of radiologic splenic vessel invasion in resectable left-sided pancreatic ductal adenocarcinoma: predictor of early systemic recurrence following upfront surgery

BACKGROUND

The aim of this study is to identify prognostic factors and the best candidates for neoadjuvant therapy among patients with resectable left-sided pancreatic ductal adenocarcinoma (PDAC) by analyzing the timing and pattern of recurrence following upfront surgery.

METHODS

This single-center retrospective study included patients with resectable left-sided PDAC who underwent upfront distal pancreatectomy from 2005 to 2015. A minimum P value approach was used to evaluate the optimal cutoff of early recurrence. The predictors of recurrence were assessed with Cox regression analysis.

RESULTS

Among 311 included patients, 241 (77.5%) had a recurrence at a median follow-up of 29.3 months. Systemic recurrence occurred in 194 patients (80.5%) and isolated local recurrence in 47 patients (19.5%). A recurrence-free survival cutoff of 12 months was selected to distinguish between early and late recurrence. The patients with early recurrence had a shorter median overall survival (16.1 vs. 39.9 months, P<0.001) and post-recurrence survival (9.6 vs. 17.2 months, P<0.001) than those with late recurrence. The patients with systemic recurrence had a shorter median overall survival (19.6 vs. 29.1 months, P=0.007) and post-recurrence survival (11.0 vs. 15.3 months, P=0.024) than those with an isolated local recurrence. In multivariable analysis, preoperative CA 19-9 ≥500 U/mL [odd ratio (OR) 2.037, P=0.035], radiologic splenic vessels invasion (OR 5.014, P<0.001), positive radial resection margin (OR 2.638, P<0.001), and no adjuvant chemotherapy (OR 2.084, P=0.001) were predictors of an early systemic recurrence.

CONCLUSIONS

Radiologic splenic vessels invasion may be considered to indicate a biologically borderline status in patients with anatomically resectable left-sided PDAC. Future clinical trials of neoadjuvant therapy targeting these patients should be conducted.

High SUVmax on routine pre-operative FDG-PET predicts early recurrence in pancreatic and peri-ampullary cancer

BACKGROUND

SUVmax of a primary pancreatic tumour on FDG-PET/CT (SUVmax-p) may predict early post-operative recurrence. This has not been tested in the context of routine pre-operative FDG-PET/CT. It is also unknown whether this association exists independent of local residual tumour.

METHODS

FDG-PET/CT was performed routinely prior to resection of pancreatic or peri-ampullary adenocarcinoma between 2008 and 2012 as part of a previous prospective study. We compared SUVmax-p according to whether recurrence was diagnosed within 6 months of resection. We also determined the odds ratio for recurrence within 6 months for multiple cut-points of SUVmax-p. This analysis was repeated exclusively for patients who had resection with clear surgical margins (R0).

RESULTS

Of 56 patients from the initial study 23 underwent resection and were eligible. Recurrence within 6 months was associated with higher median SUVmax-p (5.9 vs 3.5; p = 0.04). This was also observed in 12 patients who underwent R0 resection (6.5 vs 2.2; p = 0.05). The cut-point with the highest odds for recurrence within 6 months for both groups was SUVmax-p ≥ 5.5 (OR = 10.8, CI = 1.56-109; OR[R0] = 24.0, CI = 1.64-1020).

CONCLUSION

SUVmax-p on routine FDG-PET/CT is useful for identifying patients likely to benefit from additional pre-operative staging or neoadjuvant therapy, even where clear margins can confidently be achieved.

Prediction of local tumor control and recurrence-free survival in patients with pancreatic cancer undergoing curative resection after neoadjuvant chemoradiotherapy

BACKGROUND AND OBJECTIVES

There is little data on the correlation between the reduction in fluorodeoxyglucose positron emission tomography (FDG-PET) radioactive accumulation and carbohydrate antigen 19-9 (CA19-9) levels with pathological tumor responses (PTRs) and prognosis after neoadjuvant chemoradiotherapy (NACRT) for patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

This study was a retrospective analysis of prospectively collected data from 102 patients with resectable (R-) and borderline resectable (BR-) PDAC who received NACRT, followed by curative resection. Data were prospectively collected and compared between the responders and nonresponders to NACRT.

RESULTS

Patients with 60% or more reduction in maximum standardized uptake value (SUVmax) on FDG-PET, with 75% or more reduction in CA19-9 levels, or with 50%-100% of tumor cells destroyed due to NACRT had significantly better recurrence-free survival (RFS) than each of the nonresponders (p = 0.028, <0.001, and 0.022, respectively). The reduction rates of SUVmax and CA19-9 levels were correlated with PTR. The combined evaluation of these biomarkers reflected RFS.

CONCLUSIONS

Reduction rates of FDG uptake and CA19-9 levels were preoperative predictors of pathological response to NACRT. These biomarkers of local response had prognostic value in R-PDAC and BR-PDAC. The combined evaluation of these biomarkers allowed for reliable prediction of RFS after surgery.

Clinical Impact of Dual Time Point 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography Fusion Imaging in Pancreatic Cancer

We examined the value of preoperative dual time point (DTP) 18F-fluorodeoxyglucose positron emission tomography/computed tomography fusion imaging (FDG PET/CT) as a predictor of early recurrence or the outcomes in patients with pancreatic cancer. Standardized uptake values (SUVs) in DTP FDG PET/CT were performed as preoperative staging. SUVmax1 and SUVmax2 were obtained in 60 min and 120 min, respectively. ΔSUVmax% was defined as (SUVmax2 − SUVmax1)/SUVmax1 × 100. The optimal cut-off values for SUVmax parameters were selected based on tumor relapse within 1 year of surgery. Optimal cut-off values for SUVmax1 and ΔSUVmax% were 7.18 and 24.25, respectively. The combination of SUVmax1 and ΔSUVmax% showed higher specificity and sensitivity, and higher positive and negative predictive values for tumor relapse within 1 year than SUVmax1 alone. Relapse-free survival (RFS) was significantly worse in the subgroups of high SUVmax1 and high ΔSUVmax% (median 7.0 months) than in the other subgroups (p < 0.0001). The multivariate Cox analysis of RFS identified high SUVmax1 and high ΔSUVmax% as independent prognostic factors (p = 0.0060). DTP FDG PET/CT may effectively predict relapse in patients with pancreatic cancer. The combination of SUVmax1 and ΔSUVmax% identified early recurrent patient groups more precisely than SUVmax1 alone.

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.

Efficacy and Safety of Neoadjuvant Chemoradiation Therapy Administered for 5 Versus 2 Weeks for Resectable and Borderline Resectable Pancreatic Cancer

OBJECTIVES

Indications of preoperative treatment for resectable (R-) or borderline resectable (BR-) pancreatic ductal adenocarcinoma (PDAC) are unclear, and the protocol remains to be standardized.

METHODS

Included 65 patients with R- and BR-PDAC with venous involvement (V-) received neoadjuvant chemoradiotherapy with S-1 and 50 Gy of radiation as the 5-week regimen. The outcomes of this group were compared with those of 52 patients who underwent S-1 and 30 Gy of radiation as the 2-week regimen, previously collected as our prospective phase II study.

RESULTS

Compared with the 2-week regimen, there were no significant differences in the rate of protocol completion, adverse events, mortality and morbidity, or R0 resection in the 5-week regimen. In subgroup analyses of R-PDAC, there were no significant differences in overall survival and recurrence-free survival between the groups. In contrast, the 5-week regimen had significantly better overall survival and recurrence-free survival than the 2-week regimen for BRV-PDAC. Similar results were observed after propensity score matching analysis.

CONCLUSIONS

The 5-week regimen of neoadjuvant chemoradiotherapy has good clinical efficacy and safety for R- and BRV-PDAC. The 5-week regimen could achieve better outcomes than the 2-week regimen for BRV-PDAC. In contrast, both regimens achieved similar outcomes for R-PDAC.

Preoperative FDG-Positive Lymph Nodes Predict the Postoperative Prognosis in Resectable Biliary Tract Cancers

BACKGROUND

F-18 fluorodeoxyglucose-positron emission tomography (FDG-PET) has been used to diagnose and stage various cancers. In regard to biliary tract cancer (BTC), due to cholangitis it is difficult to evaluate FDG uptake caused by cancer. We previously showed that FDG-positive lymph nodes (LNs) of resectable BTC had a possibility of predicting postoperative prognosis.

OBJECTIVE

This study aimed to validate the usability of FDG-PET for LNs using another cohort and to investigate in detail the relationship between FDG-positive LNs and the prognosis of BTC.

METHODS

We measured the preoperative maximum standardized uptake value (SUV_max) at each of the 190 surgically dissected LN areas in 67 patients and investigated the prognosis using our previously determined SUV_max cut-off values of ≥ 2.8.

RESULTS

Regarding the prognosis of patients with resectable BTC, a LN SUV_max ≥ 2.8 [PET N (+)] was a poor prognostic factor for recurrence-free survival (RFS) compared with a LN SUV_max < 2.8 [PET N (-)]. It was confirmed that the hazard ratio forest plot [PET N (+)/PET N (-)] for RFS indicated a similar tendency among subcategories. Moreover, we investigated patients with pN0 disease and demonstrated that the PET N (+) group also had a significantly worse RFS outcome compared with the PET N (-) group. Recurrence of the PET N (+) group has significantly occurred more often in LNs than that of the PET N (-) group.

CONCLUSION

High LN SUV_max was confirmed to be the preoperatively diagnosed prognostic risk factor for RFS in resectable BTC and could be helpful for clinical decision making regarding the perioperative treatment strategy.

Pancreatic Ductal Adenocarcinoma: The Dawn of the Era of Nuclear Medicine?

Pancreatic ductal adenocarcinoma (PDAC), accounting for 90-95% of all pancreatic tumors, is a highly devastating disease associated with poor prognosis. The lack of accurate diagnostic tests and failure of conventional therapies contribute to this pejorative issue. Over the last decade, the advent of theranostics in nuclear medicine has opened great opportunities for the diagnosis and treatment of several solid tumors. Several radiotracers dedicated to PDAC imaging or internal vectorized radiotherapy have been developed and some of them are currently under clinical consideration. The functional information provided by Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT) could indeed provide an additive diagnostic value and thus help in the selection of patients for targeted therapies. Moreover, the therapeutic potential of β-- and α-emitter-radiolabeled agents could also overcome the resistance to conventional therapies. This review summarizes the current knowledge concerning the recent developments in the nuclear medicine field for the management of PDAC patients.

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

BACKGROUND

An accurate evaluation of neoadjuvant treatment is important to maximize the prognostic benefit of this strategy in each individual patient. The main aim of the present study is to investigate the difference between carbohydrate antigen 19-9 and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) in evaluating the response to neoadjuvant treatment for resectable and borderline resectable pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

Pancreatic ductal adenocarcinoma patients with positive standard uptake values (SUV) on FDG-PET before neoadjuvant chemoradiotherapy (NACRT) were enrolled (n = 141). In all patients, CA19-9 and FDG-PET were evaluated before the initiation of and after the completion of NACRT. The statuses of CA19-9 and FDG uptake alterations during NACRT were assessed in association with survival and tumor recurrence profiles.

RESULTS

A favorable response in each CA19-9 and FDG-PET was significantly related to better survival, respectively, than the unfavorable response (44.3% vs 19.5%, P < .001 and 45.8% vs 24.6%, P < .001). The status of CA19-9 was significantly associated with the incidence of distant recurrence whereas the status of FDG-PET was significantly associated with the incidence of local recurrence, and only patients with a favorable response in both CA19-9 and PET statuses showed a significantly better survival than the others (5-year survival: 56% vs 24%, P < .001), and those with unfavorable response in either of CA19-9 or PET status showed similar poor survival to those with unfavorable in both (P = .164).

CONCLUSION

CA19-9 and PET evaluation provided oncologically different risk assessments in terms of tumor recurrence profile, and favorable response in both CA19-9 and FDG-PET were necessary to achieve prognostic benefit from NACRT.

Stomatin‑like protein 2 induces metastasis by regulating the expression of a rate‑limiting enzyme of the hexosamine biosynthetic pathway in pancreatic cancer

Stomatin-like protein 2 (SLP-2) is associated with poor prognosis in several types of cancer, including pancreatic cancer (PC); however, the molecular mechanism of its involvement remains elusive. The present study aimed to elucidate the role of this protein in the development of PC. Human PC cell lines AsPC-1 and PANC-1 were transfected by a vector expressing SLP-2 shRNA. Analyses of cell proliferation, migration, invasion, chemosensitivity, and glucose uptake were conducted, while a mouse xenograft model was used to evaluate the functional role of SLP-2 in PC. Immunohistochemical analysis was retrospectively performed on human tissue samples to compare expression between the primary site (n=279) and the liver metastatic site (n=22). Furthermore, microarray analysis was conducted to identify the genes correlated with SLP-2. In vitro analysis demonstrated that cells in which SLP-2 was suppressed exhibited reduced cell motility and glucose uptake, while in vivo analysis revealed a marked decrease in the number of liver metastases. Immunohistochemistry revealed that SLP-2 was increased in liver metastatic sites. Microarray analysis indicated that this protein regulated the expression of glutamine-fructose-6-phosphate transaminase 2 (GFPT2), a rate-limiting enzyme of the hexosamine biosynthesis pathway. SLP-2 contributed to the malignant character of PC by inducing liver metastasis. Cell motility and glucose uptake may be induced via the hexosamine biosynthesis pathway through the expression of GFPT2. The present study revealed a new mechanism of liver metastasis and indicated that SLP-2 and its downstream pathway could provide novel therapeutic targets for PC.

Basal microvilli define the metabolic capacity and lethal phenotype of pancreatic cancer

Apical microvilli of polarized epithelial cells govern the absorption of metabolites and the transport of fluid in tissues. Previously, we reported that tall and dense basal microvilli present on the endothelial cells of pancreatic cancers, a lethal malignancy with a high metabolism and unusual hypomicrovascularity, contain nutrient trafficking vesicles and glucose; their length and density were related to the glucose uptake of pancreatic cancers in a small-scale analysis. However, the implications of basal microvilli on pancreatic cancers are unknown. Here, we evaluated the clinical implications of basal microvilli in 106 pancreatic cancers. We found that basal microvilli are a dominant change in pancreatic cancers. The presence of longer and denser basal microvilli on the microvessels in pancreatic cancer tissues positively correlated with increased glucose uptake and higher metastatic (or invasive) and proliferative potentials of neoplastic cells and vice versa. Clinically, postoperative patients with longer and denser basal microvilli were more prone to unfavorable pathological characteristics and dismal prognoses. They were even more refractory to adjuvant therapy than those with shorter and thinner basal microvilli were. Our findings show that basal microvilli define the metabolic capacity and lethal phenotype of pancreatic cancers. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd. on behalf of The Pathological Society of Great Britain and Ireland.

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.

Comparing prognostic factors of Glut-1 expression and maximum standardized uptake value by FDG-PET in patients with resectable pancreatic cancer

BACKGROUND

This study aimed to assess the prognostic values of preoperative maximum standardized uptake value (SUVmax) of primary pancreatic tumors and Glut-1 expression in patients with resectable pancreatic ductal adenocarcinoma (R-PDAC), and to investigate whether Glut-1 expression is more effective than SUVmax in predicting survival in patients with R-PDAC.

METHODS

We investigated 101 R-PDAC patients who underwent pancreatectomy for pancreatic cancer treatment. SUVmax analyzed through ¹⁸F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT), and Glut-1 expression, were assessed for predicting the prognosis of patients with R-PDAC.

RESULTS

In patients with R-PDAC, the high SUVmax group (≥4.25) had significantly shorter overall survival (OS) and disease-free survival (DFS) than the low SUVmax group (＜4.25). Surprisingly, Glut-1 expression was not significantly correlated with SUVmax. Moreover, the high Glut-1 expression group, which was related to higher levels of CA 19-9, had significantly shorter OS and DFS than the low Glut-1 expression group. Furthermore, among the high SUVmax group, OS and DFS were significantly shorter in the high Glut-1 expression group. Multivariate analyses revealed that Glut-1 overexpression was an independent prognostic factor in patients with R-PDAC. Glut-1 knockdown also induced cell cycle arrest in PDAC cells in vitro.

CONCLUSIONS

The study determined that Glut-1 overexpression is a more powerful prognostic factor than SUVmax for predicting OS and higher risk of recurrence in R-PDAC patients. Glut-1 overexpression is also more likely to be associated with malignant activity in PDAC patients.

Prognosis prediction of pancreatic cancer after curative intent surgery using imaging parameters derived from F-18 fluorodeoxyglucose positron emission tomography/computed tomography

Imaging parameters including metabolic or textural parameters during F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) are being used for evaluation of malignancy. However, their utility for prognosis prediction has not been thoroughly investigated. Here, we evaluated the prognosis prediction ability of imaging parameters from preoperative FDGPET/CT in operable pancreatic cancer patients.Sixty pancreatic cancer patients (male:female = 36:24, age = 67.2 ± 10.5 years) who had undergone FDGPET/CT before the curative intent surgery were enrolled. Clinico-pathologic parameters, metabolic parameters from FDGPET/CT; maximal standard uptake value (SUVmax), glucose-incorporated SUVmax (GI-SUVmax), metabolic tumor volume, total-lesion glycolysis, and 53 textural parameters derived from imaging analysis software (MaZda version 4.6) were compared with overall survival.All the patients underwent curative resection. Mean and standard deviation of overall follow-up duration was 16.12 ± 9.81months. Among them, 39 patients had died at 13.46 ± 8.82 months after operation, whereas 21 patients survived with the follow-up duration of 18.56 ± 9.97 months. In the univariate analysis, Tumor diameter ≥4 cm (P = .003), Preoperative Carbohydrate antigen 19-9 ≥37 U/mL (P = .034), number of metastatic lymph node (P = .048) and GI-SUVmax (P = .004) were significant parameters for decreased overall survival. Among the textural parameters, kurtosis3D (P = .052), and skewness3D (P = .064) were potentially significant predictors in the univariate analysis. However, in multivariate analysis only GI-SUVmax (P = .026) and combined operation (P = .001) were significant independent predictors of overall survival.The current research result indicates that metabolic parameter (GI-SUVmax) from FDGPET/CT, and combined operation could predict the overall survival of surgically resected pancreatic cancer patients. Other metabolic or textural imaging parameters were not significant predictors for overall survival of localized pancreatic cancer.

The Role of Imaging in Current Treatment Strategies for Pancreatic Adenocarcinoma

In pancreatic cancer, imaging plays an essential role in surveillance, diagnosis, resectability evaluation, and treatment response evaluation. Pancreatic cancer surveillance in high-risk individuals has been attempted using endoscopic ultrasound (EUS) or magnetic resonance imaging (MRI). Imaging diagnosis and resectability evaluation are the most important factors influencing treatment decisions, where computed tomography (CT) is the preferred modality. EUS, MRI, and positron emission tomography play a complementary role to CT. Treatment response evaluation is of increasing clinical importance, especially in patients undergoing neoadjuvant therapy. This review aimed to comprehensively review the role of imaging in relation to the current treatment strategy for pancreatic cancer, including surveillance, diagnosis, evaluation of resectability and treatment response, and prediction of prognosis.

Prediction of tumour grade and survival outcome using pre-treatment PET- and MRI-derived imaging features in patients with resectable pancreatic ductal adenocarcinoma

OBJECTIVES

To perform a correlation analysis between histopathology and imaging in patients with previously untreated pancreatic ductal adenocarcinoma (PDAC) and to determine the prognostic values of clinical, histological, and imaging parameters regarding overall survival (OS), disease-specific survival (DSS), and progression-free survival (PFS).

METHODS

This single-centre study prospectively included 61 patients (32 males; median age, 68.0 years [IQR, 63.0-75.0 years]) with histologically confirmed PDAC and following surgical resection who preoperatively underwent ¹⁸F-FDG PET/CT and DW-MRI. On whole lesions, we measured, using a 42% SUV_max threshold volume of interest (VOI), the following quantitative parameters: mean and maximum standardised uptake values (SUV_mean and SUV_max), total lesion glycolysis (TLG), metabolic tumour volume (MTV), mean and minimum apparent diffusion coefficient (ADC_mean and ADC_min), diffusion total volume (DTV), and MTV/ADC_min ratio. Spearman's correlation analysis was performed to assess relationships between these markers and histopathological findings from surgical specimens (stage; grade; resection quality; and vascular, perineural, and lymphatic invasion). Kaplan-Meier and Cox hazard ratio methods were used to evaluate the impacts of imaging parameters on OS (n = 41), DSS (n = 36), and PFS (n = 41).

RESULTS

Inverse correlations between ADC_min and SUV_max (rho = - 0.34; p = 0.0071), and between SUV_mean and ADC_mean (rho = - 0.29; p = 0.026) were identified. ADC_min was inversely correlated with tumour grade (rho = - 0.40; p = 0.0015). MTV was an independent predictive factor for OS and DSS, while DTV was an independent predictive factor for PFS.

CONCLUSION

In previously untreated PDAC, ADC and SUV values are correlated. Combining PET-MRI metrics may help predict PDAC grade and patients' survival.

KEY POINTS

• Minimum apparent diffusion coefficient derived from DW-MRI inversely correlates with tumour grade in pancreatic ductal adenocarcinoma. • In pancreatic ductal adenocarcinoma, metabolic tumour volume has been confirmed as a predictive factor for patients' overall survival and disease-specific survival. • Combining PET and MRI metrics may help predict grade and patients' survival in pancreatic ductal adenocarcinoma.

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

PURPOSE

To investigate the value of 18 FDG PET/CT volumetric parameters in the prediction of overall survival (OS) in patients with pancreatic cancer and also, assess their independence relative to well-established clinico-pathological variables.

METHODS

We conducted a retrospective analysis of patients with a confirmed diagnosis of pancreatic cancer who underwent 18 FDG PET/CT. The tumour maximum standardised uptake value (SUVmax) in addition to SUVmean, metabolic tumour volume (MTV) and total lesion glycolysis (TLG) were calculated. The prognostic value of 18 FDG PET/CT and clinico-pathological parameters for OS were assessed using univariate and multivariable analyses.

RESULTS

A sum of 89 patients were analysed in this study. Median survival for patients categorised as having high TLG (≥55) and low TLG (<55) was 18 vs 5 months (p < 0.001). Similarly, the respective high vs low SUVmean, MTV and SUVmax were 18 vs 6 months (p = 0.001), 16 vs 6 months (p = 0.002) and 18 vs 6 months (p = 0.001). Univariate analysis showed SUVmax, SUVmean, MTV, TLG, tumour size, tumour differentiation and presence of distant metastasis as prognostic factors for OS. On multivariable analysis, TLG (HR 2.0, 95% CI 1.26-3.18, p = 0.004) and the presence of distant metastasis (HR 3.37, 95% CI 1.97-5.77, p < 0.001) emerged as independent prognostic factors. Subgroup analysis identified TLG as the only significant PET metric after adjusting for the presence of distant metastasis.

CONCLUSIONS

18 FDG PET/CT is a useful tool in the preoperative evaluation of patients with pancreatic cancer. Tumour TLG offer an independent prognostic value in both potentially operable and metastatic disease settings.

Prognostic Implications of 18-FDG Positron Emission Tomography/Computed Tomography in Resectable Pancreatic Cancer

There are currently no known preoperative factors for determining the prognosis in pancreatic cancer. The aim of this study was to examine the role of 18-fluorodeoxyglucose (18-FDG) positron emission tomography/computed tomography (18-FDG-PET/CT) as a prognostic factor for patients with resectable pancreatic cancer. Data were obtained from a retrospective analysis of patients who had a preoperative PET scan and then underwent pancreatic resection from January 2007 to December 2015. The maximum standardized uptake value (SUVmax) of 18-FDG-PET/CT was calculated. Patients were divided into high (>3.65) and low (≤3.65) SUVmax groups, and compared in terms of their TNM classification (Union for International Cancer Contro classification), pathological grade, surgical treatment, state of resection margins, lymph node involvement, age, sex, diabetes and serum Carbohydrate Antigen 19-9 (CA 19-9) levels. The study involved 144 patients, 82 with high SUVmax pancreatic cancer and 62 with low SUVmax disease. The two groups’ disease-free and overall survival rates were significantly influenced by tumor stage, lymph node involvement, pathological grade, resection margins and SUVmax. Patients with an SUVmax ≤ 3.65 had a significantly better survival than those with SUVmax > 3.65 (p < 0.001). The same variables were independent predictors of survival on multivariate analysis. The SUVmax calculated with 18-FDG-PET/CT is an important prognostic factor for patients with pancreatic cancer, and may be useful in decisions concerning patients’ therapeutic management.

Evaluation of Fluorodeoxyglucose Positron Emission Tomography Scanning in the Neoadjuvant Therapy Paradigm in Pancreatic Ductal Adenocarcinoma

OBJECTIVES

Little data exist on the utility of fluorodeoxyglucose positron emission tomography (FDG-PET) in operable pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant (NA) therapy.

METHODS

Consecutively treated patients with potentially operable PDAC were recruited from a quaternary referral center between 2015 and 2018. Data were collated on demographic, clinical, radiological, treatment, and disease-free and overall survival (OS) outcome measures, correlated with FDG-PET findings.

RESULTS

Of 115 patients recruited, 61% were deemed upfront operable (n = 70), 33% borderline (n = 38), and 6% (n = 7) locally advanced. Ninety-five (83%) received NA chemotherapy with 23 (24%) sequential radiotherapy. Sixty-nine (73%) treated with NA were resected, 37 (54%) attained an R0 resection, 43 (62%) had N1 disease with median tumor viability of 50%. The median OS in the entire cohort was 30.48 months and in those who received NA chemotherapy followed by resection 37.98 months. Twelve percent (n = 13) were upstaged during NA therapy by PET. Preoperative standardized uptake value maximum of less than 5 versus 5 or greater after NA predicted for improved OS, 42.95 months versus 26.05 months, P = 0.02.

CONCLUSIONS

In this real-world cohort study of PDAC, the utility of FDG-PET in informing the patient treatment pathway was meaningfully demonstrated.

Diffusion-weighted MRI predicts the histologic response for neoadjuvant therapy in patients with pancreatic cancer: a prospective study (DIFFERENT trial)

PURPOSE

Pre-operative prediction of histological response to neoadjuvant therapy aids decisions regarding surgical management of borderline resectable pancreatic cancer (BRPC). We elucidate correlation between pre-/post-treatment whole-tumor apparent diffusion coefficient (ADC) value and rate of tumor cell destruction. We newly verify whether post-treatment ADC value at the site of vascular contact predicts R0 resectability of BRPC.

METHODS

We prospectively reviewed 28 patients with BRPC who underwent diffusion-weighted magnetic resonance imaging before neoadjuvant chemotherapy and surgery. Correlation between the percentage of tumor cell destruction and various parameters was analyzed. Strong parameters were assessed for their ability to predict therapeutic histological response and R0 resectability.

RESULTS

Pre-/post-treatment whole-tumor ADC value correlated with tumor cell destruction rate by all parameters (R = 0.630/0.714, P < 0.001/< 0.0001). The post-treatment cutoff value of ADC at the site of vascular contact for discriminating histological response of tumor destruction of ≤ 50% and tumor destruction of > 50% was determined at 1.42 × 10^-3 mm²/s. It predicts R0 with 88% sensitivity, 50% specificity, and 61% accuracy. For histological response, the post-treatment whole-tumor ADC cutoff value for discriminating between tumor destruction of ≤ 50% and tumor destruction of > 50% was determined at 1.40 × 10^-3 mm²/s. It predicts histological response with 100% sensitivity, 81% specificity, and 89% accuracy. It predicts R0 with 88% sensitivity, 70% specificity, and 75% accuracy.

CONCLUSIONS

Post-treatment whole-tumor ADC value may be a predictor of R0 resectability in patients with BRPC. Tumor cell destruction rate is indicated by the difference between pre-/post-treatment ADC values. This difference is strongly affected by the pre-treatment ADC value. The cutoff value of ADC at the site of vascular contact could not discriminate R0 resectability.

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.

18F-FDG PET/CT in pancreatic adenocarcinoma: A role at initial imaging staging?

Pancreatic ductal adenocarcinoma represents 90% of all pancreatic tumors. The only hope for prolonged survival in patients with this condition still remains surgery with complete R0 resection. Initial imaging has a pivotal role to identify patients who are eligible to curative surgery and those who may benefit of neoadjuvant chemotherapy. This review provides an analysis of the recent literature on 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) in pancreatic adenocarcinoma. Performances of FDG PET in the detection of lymph node involvement and metastatic spread at initial staging and those in the assessment of response to treatment are described.

Long-term outcomes after an aggressive resection of adenosquamous carcinoma of the pancreas

PURPOSE

Adenosquamous carcinoma (ASC) of the pancreas is a rare malignancy, associated with a poor prognosis after surgical resection, with reported median survival times (MSTs) ranging from 4.4 to 13.1 months. We conducted this study to investigate the long-term outcomes of patients after the resection for ASC.

METHODS

Between 2002 and 2016, a total of 456 patients underwent resection for ASC or adenocarcinoma (AC) of the pancreas. ASC was confirmed in 17 (3.7%) of these patients. We analyzed the clinicopathological characteristics and survival of these 17 patients in comparison with those of patients with AC of the pancreas.

RESULTS

The operative procedures performed were pancreaticoduodenectomy (n = 6) and distal pancreatectomy (n = 11). Seven (41.2%) of the 17 patients underwent combined organ resection. R0 resection was achieved in 16 (94.1%) patients. The 5-year overall survival (OS) rate and MST were 40.3% and 20.9 months, respectively. A squamous component of ≥ 60% (P = 0.001) and R1 resection (P < 0.001) were significantly associated with poor OS for patients with ASC CONCLUSION: This study revealed longer survival and a higher R0 resection rate after aggressive combined resection in our ASC patients than those in previous studies. Although this was only a small series, our findings suggest that local control with aggressive resection may be an effective treatment protocol for ASC patients.

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

PURPOSE

To evaluate the prognostic value of preoperative 18-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in patients with potentially resectable pancreatic cancer.

METHODS

The study included 103 consecutive patients with potentially resectable pancreatic cancer who underwent preoperative FDG-PET/CT. Age, sex, blood glucose level, tumor marker levels (carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA19-9)), PET-related parameters (maximum standardized uptake value (SUVmax)), and contrast-enhanced CT-related factors (tumor size, location, enhancement pattern, and CT-based T and N factors by tumor nodes metastasis (TNM) classification) were assessed for their ability to independently predict postoperative tumor recurrence using Cox proportional hazards model.

RESULTS

Median follow-up was 23.1 months. Univariate analyses revealed that SUVmax (P = 0.0004), tumor size (P = 0.0002), T factor (P = 0.0102), N factor (P = 0.0049), and CA19-9 levels (P = 0.0059) were significantly associated with disease-free survival (DFS). In multivariate analysis, SUVmax (P = 0.0163) and CA19-9 levels (P = 0.0364) independently predicted DFS. Kaplan-Meier analysis revealed that patients with low (< 2.5) SUVmax had a significantly better prognosis than those with higher SUVmax (P = 0.0006). The DFS in patients with SUVmax < 2.5 (n = 23) and SUVmax ≥ 2.5 (n = 80) was 61.9% and 9.7%, respectively, 3 years postoperatively.

CONCLUSIONS

SUVmax can predict DFS in patients with resectable pancreatic cancer. A SUVmax < 2.5 heralds a better prognosis.

Clinical impact of fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography in patients with resectable pancreatic cancer: diagnosing lymph node metastasis and predicting survival

PURPOSE

To evaluate the diagnostic accuracy of fluorine-18-fluorodeoxyglucose PET/computed tomography (F-FDG PET/CT) for lymph node (LN) metastasis and the prognostic significance of F-FDG PET/CT LN parameters in patients with resectable pancreatic cancer.

PATIENTS AND METHODS

Patients with resectable pancreatic cancer who underwent staging F-FDG PET/CT between May 2007 and September 2016 were retrospectively enrolled and analyzed through medical record and image re-evaluation. The diagnostic accuracy of F-FDG PET/CT in predicting LN metastasis was evaluated and compared with that of contrast-enhanced abdominal computed tomography (CECT). Prognostic variables, including LN parameters assessed by F-FDG PET/CT [standardized uptake value (SUV)LN and LN/tumor SUV ratio], that affect disease-free survival (DFS) and overall survival (OS) were evaluated by regression analysis.

RESULTS

When predicting LN metastasis, F-FDG PET/CT showed greater sensitivity, positive predictive value, negative predictive value, and accuracy than CECT. Among prognostic factors affecting DFS, PET-positive LN (P=0.008), and LN/tumor SUV ratio (P=0.003) were found to be significant by regression analysis. Among the variables affecting OS, lymphovascular invasion (P=0.018) and the LN/tumor SUV ratio (P=0.046) were found to be significant.

CONCLUSION

F-FDG PET/CT showed higher diagnostic accuracy in predicting LN metastasis than CECT in patients with resectable pancreatic cancer. Only the LN/tumor SUV ratio of F-FDG PET/CT was an independent prognostic variable in both DFS and OS.

Prognostic value of metabolic parameters on preoperative 18F-fluorodeoxyglucose positron emission tomography/ computed tomography in patients with stage III gastric cancer

This study investigated the prognostic value of metabolic parameters determined by 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with stage III gastric cancer. Patients with pre-operative PET/CT and confirmed stage III after curative surgical resection were retrospectively enrolled. Parameters evaluated from pre-operative PET/CTwere maximum standardized uptake value (SUV_max) and peak SUV (SUV_peak) of primary tumor, SUV_max or SUV_peak of tumor to liver ratio (TLR_max and TLR_peak). Volumetric parameters, metabolic tumor volume (MTV) and total lesion glycolysis (TLG), were also evaluated. These PET/CT parameters were compared with the overall survival (OS) and recurrence-free survival (RFS). From total of 133 consecutive patients, tumor recurrence was found in 54 patients (40.6%) and 53 died during the follow-up period (median, 43 mo; range 5-62). In univariate analysis, SUV_max, SUV_peak, TLR_max and TLR_peak were significantly associated with the OS and RFS. In multivariate analysis, high TLR_max and TLR_peak were significantly unfavorable prognostic factors for RFS (both P<0.05) even after adjusting for age, depth of tumor invasion, lymph node metastasis, and chemotherapy. MTV and TLG showed no statistically significant correlation with outcome. In conclusion, glucose metabolism of primary tumor measured by pre-operative PET/CT provides prognostic information, especially for recurrence, in stage III gastric cancer.

Preoperative neutrophil-to-lymphocyte ratio as a prognosticator in early stage pancreatic ductal adenocarcinoma

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR), which reflects the cancer-induced systemic inflammation response, has been proposed as a risk factor for poor long-term prognosis in cancer. We investigated the prognostic role of the NLR and the relationship between the NLR and TNM stage in pancreatic ductal adenocarcinoma (PDAC) patients following curative resection.

METHODS

One-hundred thirty-eight consecutive patients with resected PDAC were enrolled between 2004 and 2014. Univariate and multivariate analyses identified variables associated with overall survival (OS) and recurrence-free survival (RFS). Patients were stratified according to the NLR, with an NLR cut-off value of 2.2 being estimated by receiver operating characteristic curve.

RESULTS

Compared to patients with a low NLR (≤2.2), those with a high preoperative NLR (>2.2) had worse OS and RFS (P = 0.017, P = 0.029, respectively). For early-stage tumors, tumor size ≥20 mm and a high NLR were independent risk factors for poor OS (hazard ratio (HR): 3.255, 95% confidence interval (CI): 1.082-9.789, P = 0.036; HR: 3.690, 95% CI: 1.026-13.272, P = 0.046, respectively) and RFS (HR: 3.575, 95% CI: 1.174-10.892, P = 0.025; HR: 5.380, 95% CI: 1.587-18.234, P = 0.007, respectively). The NLR was not correlated with prognosis in patients with advanced stages.

CONCLUSIONS

An elevated preoperative NLR was an important prognosticator for early TNM stage PDAC. The NLR, which is calculated using inexpensive and readily available biomarkers, could be a novel tool for predicting long-term survival in patients, especially those with early stage PDAC.

18-Fluorodeoxyglucose Positron Emission Tomography Predicts Recurrence in Resected Pancreatic Ductal Adenocarcinoma

BACKGROUND

We aimed to determine whether treatment should be stratified according to 18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) maximum standardized uptake values (SUV_max) in pancreatic ductal adenocarcinoma.

METHODS

Patients who underwent preoperative 18F-FDG PET/CT between 2006 and 2014 (n = 138) were stratified into high (≥ 4.85) and low (< 4.85) PET groups. The clinicopathological characteristics and prognostic outcomes were analyzed retrospectively.

RESULTS

The primary tumor SUV_max was positively correlated with preoperative CA19-9 levels (P < 0.001). The high PET group failed to achieve postoperative CA19-9 normalization (P = 0.014). Disease-specific (P < 0.001), recurrence-free (P < 0.001), liver recurrence-free (P < 0.001), and peritoneal recurrence-free (P = 0.020) survivals were significantly shorter in the high PET group. The primary tumor SUV_max was an independent predictive risk factor for liver metastasis (hazard ratio 3.46, 95% confidence interval 1.61-7.87; P = 0.001) and peritoneal recurrence (hazard ratio 3.36, 95% confidence interval 1.18-10.89; P = 0.023).

CONCLUSIONS

Surgical resection failed to achieve CA19-9 normalization in the high PET group and distant recurrence was frequent. This suggests the potential for residual cancer at distant sites, even after curative resection. Stronger preoperative systemic chemotherapy is preferred for the high PET group patients.

The Role of 18F-FDG PET/CT and PET/MRI in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains a difficult disease to treat and continues to portend a poor prognosis, as most patients are unresectable at diagnosis. 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) combined with CT (PET/CT) has been a cornerstone in oncological imaging of different cancers; however, the role of PET/CT in PDAC is continually evolving and currently not well established. Studies have shown the potential of PET/CT in guiding the management of patients with PDAC, with possible added benefit over anatomic imaging with CT or MRI in certain scenarios. PET/CT may be useful in diagnosis, initial staging, treatment response assessment, differentiation of recurrent tumor from post-treatment fibrosis, and radiotherapy planning. Additionally, PET/CT may be a cost-effective modality due to upstaging of patients originally deemed as surgical candidates. Recently, the advent of simultaneous PET/MRI represents an exciting advancement in hybrid functional imaging with potential applications in the imaging of PDAC. The advantages of PET/MRI include simultaneous acquisition to improve registration of fusion images, lower radiation dose, superior soft tissue contrast, and availability of multiparametric imaging. Studies are underway to evaluate the utility of PET/MRI in PDAC, including in initial staging and treatment response assessment and to determine the subgroup of patients that will benefit from PET/MRI. Further studies are warranted in both PET/CR and PET/MRI to better understand the role of these modalities in PDAC.

Survival Prediction in Pancreatic Ductal Adenocarcinoma by Quantitative Computed Tomography Image Analysis

BACKGROUND

Pancreatic cancer is a highly lethal cancer with no established a priori markers of survival. Existing nomograms rely mainly on post-resection data and are of limited utility in directing surgical management. This study investigated the use of quantitative computed tomography (CT) features to preoperatively assess survival for pancreatic ductal adenocarcinoma (PDAC) patients.

METHODS

A prospectively maintained database identified consecutive chemotherapy-naive patients with CT angiography and resected PDAC between 2009 and 2012. Variation in CT enhancement patterns was extracted from the tumor region using texture analysis, a quantitative image analysis tool previously described in the literature. Two continuous survival models were constructed, with 70% of the data (training set) using Cox regression, first based only on preoperative serum cancer antigen (CA) 19-9 levels and image features (model A), and then on CA19-9, image features, and the Brennan score (composite pathology score; model B). The remaining 30% of the data (test set) were reserved for independent validation.

RESULTS

A total of 161 patients were included in the analysis. Training and test sets contained 113 and 48 patients, respectively. Quantitative image features combined with CA19-9 achieved a c-index of 0.69 [integrated Brier score (IBS) 0.224] on the test data, while combining CA19-9, imaging, and the Brennan score achieved a c-index of 0.74 (IBS 0.200) on the test data.

CONCLUSION

We present two continuous survival prediction models for resected PDAC patients. Quantitative analysis of CT texture features is associated with overall survival. Further work includes applying the model to an external dataset to increase the sample size for training and to determine its applicability.

Microscopic Venous Invasion in Pancreatic Cancer

BACKGROUND

Microscopic venous invasion (MVI) and the subsequent peripheral blood circulation of cancer cells are considered to be the primary route for systemic dissemination of pancreatic cancer.

METHODS

Patients who underwent pancreatectomy for invasive ductal carcinoma of the pancreas between January 2007 and December 2015 were retrospectively reviewed. The prognostic significance of MVI was analyzed.

RESULTS

A total of 352 patients underwent pancreatectomy for invasive ductal carcinoma of the pancreas. A pathologic examination showed MVI in 228 (64.5%) of the patients. The median survival time (MST) was 21 months for the patients with MVI and 58 months for those without MVI (p < 0.001). A multivariate analysis showed the following to be significant prognostic factors: non-administration of adjuvant chemotherapy [hazard ratio (HR) 2.37; p < 0.001], lymph node metastasis (HR 2.95; p = 0.001), CA19-9 value of 300 U/ml or higher (HR 1.70; p = 0.018), and MVI (HR 1.84; p = 0.011). The overall survival was clearly stratified into three groups; favorable (MST not reached in stage 1 or 2A without MVI; p = 0.867), moderate (30 months in stage 2A with MVI and 30 months in stage 2B without MVI; p = 0.528), and poor (19 months in stage 2B with MVI and 17 months in stage 4; p = 0.322). The differences between these three groups all were significant.

CONCLUSIONS

Approximately two-thirds of patients with radiologically resectable pancreatic cancer had MVI and were considered to have potentially systemic disease. This study identified MVI as one of the significant factors for a poor prognosis and a valuable complement of tumor-node-metastasis staging.

SUVmax after (18)fluoro-deoxyglucose positron emission tomography/computed tomography: A tool to define treatment strategies in pancreatic cancer

BACKGROUND

(18)fluoro-deoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) might be a useful tool in the management of pancreatic ductal adenocarcinoma (PDAC).

AIMS

The aim of this study was to analyze maximum standard uptake value (SUVmax) after 18FDG-PET/CT as predictor of survival outcomes and method to determine treatment strategies.

METHODS

A consecutive series of patients who underwent preoperative 18FDG-PET/CT and subsequent resection for PDAC were retrospectively reviewed. Patients who underwent neoadjuvant chemotherapy were excluded.

RESULTS

46 patients were included in the analysis. Median follow-up was 27 months (4-67). Patients who recurred within 12 months showed a significantly higher preoperative median SUVmax (8.1 vs 6.1, p=0.039). Receiver operating characteristics (ROC) curves for disease-free survival (DFS) and disease-specific survival (DSS) identified SUVmax of 6.0 as optimal cut-off. Multivariate analysis showed that SUVmax ≥ 6.0 was an independent predictor of poor DFS (HR 2.288, p=0.024) and DSS (HR 4.875, p<0.001). The combination of SUVmax ≥6.0 with CA19.9 ≥200U/ml was significantly associated with survival outcomes in comparison to patients without concordantly elevated values.

CONCLUSION

SUVmax ≥6.0 is an independent predictor of DFS and DSS in resected PDAC. 18FDG-PET/CT might be considered in the preoperative evaluation of patients with pancreatic cancer.

Investigation of Association Between Borderline Pancreatic Head Cancer and Glucose Uptake by Using Positron-Emission Tomographic Studies

BACKGROUND In the background of the well-known importance of positron-emission tomographic studies (PET) in the prediction of pancreatic oncologic problems, we designed and performed this investigation to study the link between borderline pancreatic head cancer and glucose uptake by using PET. MATERIAL AND METHODS We retrospectively investigated patients during the period of almost 4 years (May 2013 to December 2016). Patients underwent potentially curative resection for borderline exocrine pancreatic head adenocarcinoma without undergoing neoadjuvant therapy. We divided our PET protocol into 2 sets of methods as per renal calyces: 1) U-RC type in which renal calyx (RC) has relatively higher value than that of 18F-fluoro-2-deoxyglucose (18F-FDG) uptake and 2) S-RC type in which renal calyx has similar value than that of 18F-FDG uptake. RESULTS A total of 67 patients were enrolled after reclassification on the basis of majority-agreement. Among these patients, U-RC type was found in 22 patients (32.8%) while S-RC type was found in 45 patients (67.2%). Significant statistical differences were observed for each of the 2 types of pancreatic head cancer (U-RC type and S-RC type) in terms of adjusted cancer antigen 19-9 (CA 19-9), size of the tumor, tumor volume (TV2.8), maximum standard uptake value (SUV↑), and lesion glycolysis (LG). A significantly longer disease-free survival time was shown by U-RC type (n=18) pancreatic cancer in comparison to S-RC type (n=42) (25.3 vs. 11.2 months). Additionally, U-RC type (n=4) had higher disease-free survival than did aS-RC type (n=3) (29.4 vs. 12.5 months). CONCLUSIONS Our PET protocol appears to be an indicator for estimation of recurrence of pancreatic head cancer and is as an indispensable asset to oncologists.

Prognostic value of 18F-FDG-PET/CT parameters in patients with pancreatic carcinoma: A systematic review and meta-analysis

BACKGROUND

The identification of pancreatic carcinoma (PC) patients with poor prognosis is a priority in clinical oncology because of their high 5-year mortality. However, the prognostic value of pretreatment F-fluorodeoxyglucose (F-FDG)- positron emission tomography (PET)/computed tomography (CT) parameters in PC patients is controversial and no consensus exists as to its predictive capability. This meta-analysis was performed to comprehensively explore the prognostic significance of F-FDG-PET/CT parameters in patients with pancreatic carcinoma.

METHODS

Extensive literature searches of the PubMed, Embase, Web of Science, and Cochrane Library databases were conducted to identify literature published until March 5, 2017. Comparative analyses of the pooled hazard ratios (HRs) for event-free survival (EFS) and overall survival (OS) were performed to assess their correlations with pretreatment maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Either the fixed- or the random-effects model was adopted, depending on the heterogeneity observed across studies. Subgroup and sensitivity analyses were performed to assess the robustness of the results.

RESULTS

Sixteen studies including 1146 patients were identified. The pooled HRs for the probability of EFS were 1.90 (95% confidential interval (CI): 1.48-2.45) for SUVmax, 1.76 (95% CI: 1.20-2.58) for MTV, and 1.81 (95% CI: 1.27-2.58) for TLG. The pooled HRs for the probability of OS were 1.21 (95% CI: 1.12-1.31) for SUVmax, 1.56 (95% CI: 1.13-2.16) for MTV, and 1.70 (95% CI: 1.25-2.30) for TLG. A slight publication bias was detected using Begg test. After adjustment using the trim and fill procedure, the corrected HRs were not significantly different. The results of the subgroup analyses by SUVmax, MTV, and TLG showed that these factors may have similar prognostic significance.

CONCLUSION

F-FDG-PET/CT parameters, such as SUVmax, MTV, and TLG, may be significant prognostic factors in patients with pancreatic carcinoma. F-FDG-PET/CT imaging could be a promising tool to provide prognostic information for these patients.

Laparoscopic distal pancreatectomy for pancreatic ductal adenocarcinoma: Long-term oncologic outcomes after standard resection

BACKGROUND

Surgical resection is the only curative option in patients with pancreatic ductal adenocarcinoma. Little is known about the oncologic outcomes of laparoscopic distal pancreatectomy. This bi-institutional study aimed to examine the long-term oncologic results of standard laparoscopic distal pancreatectomy in a large cohort of patients with pancreatic ductal adenocarcinoma.

METHODS

From January 2002 to March 2016, 207 patients underwent standard laparoscopic distal pancreatectomy for pancreatic ductal adenocarcinoma at Oslo University Hospital-Rikshospitalet (Oslo, Norway) and Asan Medical Centre (Seoul, Republic of Korea). After the exclusion criteria were applied (distant metastases at operation, conversion to an open operation, loss to follow-up), 186 patients were eligible for the analysis. Perioperative and oncologic variables were analyzed for association with recurrence and survival.

RESULTS

Median overall and recurrence-free survivals were 32 and 16 months, while 5-year overall and recurrence-free survival rates were estimated to be 38.2% and 35.9%, respectively. Ninety-six (52%) patients developed recurrence: 56 (30%) extrapancreatic, 27 (15%) locoregional, and 13 (7%) combined locoregional and extrapancreatic. Thirty-seven (19.9%) patients had early recurrence (within 6 months of operation). In the multivariable analysis, tumor size >3 cm and no adjuvant chemotherapy were associated with early recurrence (P = .017 and P = .015, respectively). The Cox regression model showed that tumor size >3 cm and lymphovascular invasion were independent predictors of decreased recurrence-free and overall survival.

CONCLUSION

Standard laparoscopic distal pancreatectomy is associated with satisfactory long-term oncologic outcomes in patients with pancreatic ductal adenocarcinoma. Several risk factors, such as tumor size >3 cm, no adjuvant chemotherapy, and lymphovascular invasion, are linked to poor prognosis after standard laparoscopic distal pancreatectomy.

Heterogeneity index evaluated by slope of linear regression on 18F-FDG PET/CT as a prognostic marker for predicting tumor recurrence in pancreatic ductal adenocarcinoma

PURPOSE

¹⁸F-Fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) has been investigated as a method to predict pancreatic cancer recurrence after pancreatic surgery. We evaluated the recently introduced heterogeneity indices of ¹⁸F-FDG PET/CT used for predicting pancreatic cancer recurrence after surgery and compared them with current clinicopathologic and ¹⁸F-FDG PET/CT parameters.

METHODS

A total of 93 pancreatic ductal adenocarcinoma patients (M:F = 60:33, mean age = 64.2 ± 9.1 years) who underwent preoperative ¹⁸F-FDG PET/CT following pancreatic surgery were retrospectively enrolled. The standardized uptake values (SUVs) and tumor-to-background ratios (TBR) were measured on each ¹⁸F-FDG PET/CT, as metabolic parameters. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were examined as volumetric parameters. The coefficient of variance (heterogeneity index-1; SUVmean divided by the standard deviation) and linear regression slopes (heterogeneity index-2) of the MTV, according to SUV thresholds of 2.0, 2.5 and 3.0, were evaluated as heterogeneity indices. Predictive values of clinicopathologic and ¹⁸F-FDG PET/CT parameters and heterogeneity indices were compared in terms of pancreatic cancer recurrence.

RESULTS

Seventy patients (75.3%) showed recurrence after pancreatic cancer surgery (mean recurrence = 9.4 ± 8.4 months). Comparing the recurrence and no recurrence patients, all of the ¹⁸F-FDG PET/CT parameters and heterogeneity indices demonstrated significant differences. In univariate Cox-regression analyses, MTV (P = 0.013), TLG (P = 0.007), and heterogeneity index-2 (P = 0.027) were significant. Among the clinicopathologic parameters, CA19-9 (P = 0.025) and venous invasion (P = 0.002) were selected as significant parameters. In multivariate Cox-regression analyses, MTV (P = 0.005), TLG (P = 0.004), and heterogeneity index-2 (P = 0.016) with venous invasion (P < 0.001, 0.001, and 0.001, respectively) demonstrated significant results.

CONCLUSIONS

The heterogeneity index obtained using the linear regression slope, could be an effective predictor of pancreatic cancer recurrence after pancreatic cancer surgery, in addition to ¹⁸F-FDG PET/CT volumetric parameters and clinicopathologic parameters.

FDG-PET predicts treatment efficacy and surgical outcome of pre-operative chemoradiation therapy for resectable and borderline resectable pancreatic cancer

BACKGROUND

The efficacy of neoadjuvant chemoradiotherapy (NACRT) for resectable and borderline resectable pancreatic cancer is important for predicting outcomes after radical surgery, but few clinical indicators predict outcome before resection. This study examined the utility of FDG-PET in predicting the efficacy of NACRT and outcome after radical surgery.

METHODS

Eighty-three pancreatic cancer patients who underwent FDG-PET before and after NACRT and had positive standard uptake values (SUVs) before NACRT were enrolled in this study. Peri-operative clinical factors, including FDG-PET findings, were examined to predict the efficacy of NACRT and outcome after surgery.

RESULTS

Evans grade I, IIA, IIB, III, and IV was determined in 11, 31, 27, 11, and 3 patients, respectively. The maximum SUVs after NACRT (post SUV-max) and tumor size were significantly decreased compared to pretreatment values (p < 0.001 and p = 0.007, respectively). The post SUV-max and regression index were significantly related to grade III/IV (p = 0.04 and p < 0.001, respectively), but only the regression index predicted NACRT efficacy (p = 0.002). The AUC of the regression index for the detection of grade III/IV was 0.822, and 13 of 14 grade III/IV patients were picked up using 50% as the threshold (p < 0.001). Patients with a regression index >50% had a significantly better prognosis after radical resection than patients with <50% (p = 0.032). Regression index as well as pathological lymph node status and resectability status were independent prognostic factors in multivariate analysis (exp 2.086, p = 0.043).

CONCLUSION

The regression index is potentially a good indicator of the efficacy of NACRT and outcome after radical resection for pancreatic cancer.

Clinically determined type of 18F-fluoro-2-deoxyglucose uptake as an alternative prognostic marker in resectable pancreatic cancer

PURPOSE

To investigate the association between clinical PET (positron emission tomography) type and oncologic outcome in resectable pancreatic cancer.

METHODS

Between January 2008 and October 2012, patients who underwent potentially curative resection for resectable pancreatic ductal adenocarcinoma without neoadjuvant treatment were retrospectively investigated. Clinical PET type was defined as follows: pancreatic cancer with similar 18FDG uptake to renal calyx was determined as kidney-type (K-type), and relatively lower 18FDG uptake than that of renal calyx was regarded as Non-K type.

RESULTS

A total of 53 patients were enrolled. After agreement-based reclassification, agreement based K-type (aK-type) was noted in 34 patients (64.2%), and agreement based Non-K type (aNon K-type) was found in 19 patients (35.8%). There was a significant difference between aK-type and aNon K-type pancreatic cancer (tumor size (P = 0.030), adjusted CA 19-9 (P = 0.007), maximum standard uptake value (SUVmax,P<0.001), metabolic tumor volume (MTV2.5, P<0.001), total lesion glycolysis (TLG, P<0.001)). K-type pancreatic cancer (n = 31) showed a significantly shorter disease-free time compared with Non-K type (n = 16) (10.8 vs. 24.1 months, P = 0.013). It was also noted that aK-type showed inferior disease-free survival to that of aNon-K type pancreatic cancer (11.9 vs. 28.6 months, P = 0.012).

CONCLUSIONS

Clinical PET type is a reliable clinical marker to estimate aggressive tumor biology and can be utilized in predicting tumor recurrence and necessity for postoperative chemotherapy.

Employing Metabolism to Improve the Diagnosis and Treatment of Pancreatic Cancer

Pancreatic ductal adenocarcinoma is on pace to become the second leading cause of cancer-related death. The high mortality rate results from a lack of methods for early detection and the inability to successfully treat patients once diagnosed. Pancreatic cancer cells have extensively reprogrammed metabolism, which is driven by oncogene-mediated cell-autonomous pathways, the unique physiology of the tumor microenvironment, and interactions with non-cancer cells. In this review, we discuss how recent efforts delineating rewired metabolic networks in pancreatic cancer have revealed new in-roads to develop detection and treatment strategies for this dreadful disease.

Quantitative Analysis of (18)F-Fluorodeoxyglucose Positron Emission Tomography Identifies Novel Prognostic Imaging Biomarkers in Locally Advanced Pancreatic Cancer Patients Treated With Stereotactic Body Radiation Therapy

PURPOSE

To identify prognostic biomarkers in pancreatic cancer using high-throughput quantitative image analysis.

METHODS AND MATERIALS

In this institutional review board-approved study, we retrospectively analyzed images and outcomes for 139 locally advanced pancreatic cancer patients treated with stereotactic body radiation therapy (SBRT). The overall population was split into a training cohort (n=90) and a validation cohort (n=49) according to the time of treatment. We extracted quantitative imaging characteristics from pre-SBRT (18)F-fluorodeoxyglucose positron emission tomography, including statistical, morphologic, and texture features. A Cox proportional hazard regression model was built to predict overall survival (OS) in the training cohort using 162 robust image features. To avoid over-fitting, we applied the elastic net to obtain a sparse set of image features, whose linear combination constitutes a prognostic imaging signature. Univariate and multivariate Cox regression analyses were used to evaluate the association with OS, and concordance index (CI) was used to evaluate the survival prediction accuracy.

RESULTS

The prognostic imaging signature included 7 features characterizing different tumor phenotypes, including shape, intensity, and texture. On the validation cohort, univariate analysis showed that this prognostic signature was significantly associated with OS (P=.002, hazard ratio 2.74), which improved upon conventional imaging predictors including tumor volume, maximum standardized uptake value, and total legion glycolysis (P=.018-.028, hazard ratio 1.51-1.57). On multivariate analysis, the proposed signature was the only significant prognostic index (P=.037, hazard ratio 3.72) when adjusted for conventional imaging and clinical factors (P=.123-.870, hazard ratio 0.53-1.30). In terms of CI, the proposed signature scored 0.66 and was significantly better than competing prognostic indices (CI 0.48-0.64, Wilcoxon rank sum test P<1e-6).

CONCLUSION

Quantitative analysis identified novel (18)F-fluorodeoxyglucose positron emission tomography image features that showed improved prognostic value over conventional imaging metrics. If validated in large, prospective cohorts, the new prognostic signature might be used to identify patients for individualized risk-adaptive therapy.

Prognostic Value of Metabolic and Volumetric Parameters of Preoperative FDG-PET/CT in Patients With Resectable Pancreatic Cancer

In this study, we aimed to evaluate prognostic value of metabolic and volumetric parameters measured from F fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with resectable pancreatic cancer.Fifty-one patients with resectable pancreatic cancer who underwent FDG-PET/CT and curative operation were retrospectively enrolled. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured from FDG-PET/CT. Association between FDG-PET/CT and clinicopathologic parameters was evaluated. The prognostic values of the FDG-PET/CT and clinicopathologic parameters for recurrence-free survival (RFS) and overall survival (OS) were assessed by univariate and multivariate analyses.The 51 enrolled patients were followed up for a median of 21 months (mean ± SD: 23 ± 16 months, range: 1-78 months) with 33 (65%) recurrences and 30 (59%) deaths during the period. SUVmax, MTV, and TLG were associated with Tumor node metastasis (TNM) stage and presence of lymph node metastasis. MTV and TLG were associated with presence of lymphovascular invasion, whereas SUVmax was not. On the univariate analysis, SUVmax, MTV, and TLG were associated with RFS and OS. Also, lymph node metastasis and TNM stage were associated with OS on the univariate analysis. On multivariate analysis, MTV and TLG were independent prognostic factors for RFS and OS. SUVmax was an independent prognostic factor for OS, but not for RFS.Metabolic tumor volume and TLG were independently predictive of RFS and OS in resectable pancreatic cancer. SUVmax was an independent factor for OS, but not for RFS.

Preoperative Volume-Based PET Parameter, MTV2.5, as a Potential Surrogate Marker for Tumor Biology and Recurrence in Resected Pancreatic Cancer

This study aims to evaluate the role of volume-based positron emission tomography parameters as potential surrogate markers for tumor recurrence in resected pancreatic cancer. Between January 2008 and October 2012, medical records of patients who underwent surgical resection for pancreatic ductal adenocarcinoma and completed ¹⁸F-fluorodeoxyglucose positron emission tomography/CT as a part of preoperative staging work-up were retrospectively reviewed. Not only clinicopathologic variables but also positron emission tomography parameters such as SUVmax, MTV2.5 (metabolic tumor volume), and TLG (total lesion glycolysis) were obtained. Twenty-six patients were women and 31 were men with a mean age of 62.9 ± 9.1 years. All patients were preoperatively determined to resectable pancreatic cancer except 1 case with borderline resectability. R0 resection was achieved in all patients and 45 patients (78.9%) received postoperative adjuvant chemotherapy with or without radiation therapy. Median overall disease-free survival was 12.8 months with a median overall disease-specific survival of 25.1 months. SUVmax did not correlate with radiologic tumor size (P = 0.501); however, MTV2.5 (P = 0.001) and TLG (P = 0.009) were significantly associated with radiologic tumor size. In addition, MTV2.5 (P < 0.001) and TLG (P < 0.001) were significantly correlated with a tumor differentiation. There were no significant differences in TLG and SUVmax according to lymph node ratio; only MTV2.5 was related to lymph node ratio with marginal significance (P = 0.055). In multivariate analysis, lymph node ratio (Exp [β] = 2.425, P = 0.025) and MTV2.5 (Exp[β] = 2.273, P = 0.034) were identified as independent predictors of tumor recurrence following margin-negative resection. Even after tumor size-matched analysis, MTV2.5 was still identified as significant prognostic factor in resected pancreatic cancer (P < 0.05). However, preoperative neoadjuvant treatment attenuated adverse oncologic impact of high preoperative MTV2.5 (P = 0.210). Preoperatively determined volume-based PET parameter, MTV2.5, can potentially be used as a surrogate marker to estimate tumor biology and tumor recurrence. Individual treatment strategies for pancreatic cancer can be suggested based on patients' preoperative MTV2.5.