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

Postoperative Carbohydrate Antigen 19-9 Level as a Good Indicator of Ineffective Response to the Currently Recommended S-1 Adjuvant Chemotherapy for Pancreatic Ductal Adenocarcinoma: A Single-Center, Retrospective Study

PURPOSE

The intensity of adjuvant treatment for pancreatic ductal adenocarcinomas (PDACs) has not been stratified according to the risk after resection. This study was designed to identify patients with PDACs in whom the current S-1 adjuvant treatment is ineffective.

METHODS

This single-center, retrospective study included patients who underwent pancreatectomy for PDACs from 2009 to 2020 at Sendai Open Hospital and were receiving S-1 adjuvant treatment. The independent risk factors for recurrence and survival were determined by using a Cox proportional hazards regression model. The effects of S-1 adjuvant treatment and detailed patterns of recurrence were evaluated in patients with high-risk factors.

RESULTS

Overall, 118 patients with PDAC received S-1 adjuvant treatment. Postoperative nonnormalized carbohydrate antigen (CA19-9) was a predictive risk factor for recurrence (p < 0.010; hazard ratio [HR], 3.87; 95% confidence interval [CI], 2.26-6.62) and survival (p = 0.008; HR, 2.25; 95% CI, 1.24-4.11) after S-1 adjuvant treatment. In 24 patients with nonnormalized postoperative CA19-9, S-1 monotherapy was ineffective in preventing recurrence, even during the treatment period, compared with that noted in patients who did not receive adjuvant treatment. The recurrence rate during adjuvant treatment was 41.7%; in all cases, recurrence was caused by distant metastasis. The total recurrence rate was up to 95.8%, and distant recurrence was especially frequent.

CONCLUSIONS

The current S-1 adjuvant treatment regimen is ineffective for patients with postoperative nonnormalized CA19-9. The postoperative CA19-9 level may be a good indicator for further aggressive treatment. This study may lead to further discussions on intensity stratification of adjuvant treatments for PDAC.

"Conversion surgery" for locally advanced pancreatic cancer: A position paper by the study group at the joint meeting of the International Association of Pancreatology (IAP) & Japan Pancreas Society (JPS) 2022

Locally advanced pancreatic cancer (LAPC), which progresses locally and surrounds major vessels, has historically been deemed unresectable. Surgery alone failed to provide curative resection and improve overall survival. With the advancements in treatment, reports have shown favorable results in LAPC after undergoing successful chemotherapy therapy or chemoradiation therapy followed by surgical resection, so-called "conversion surgery", at experienced high-volume centers. However, recognizing significant regional and institutional disparities in the management of LAPC, an international consensus meeting on conversion surgery for LAPC was held during the Joint Congress of the 26th Meeting of the International Association of Pancreatology (IAP) and the 53rd Annual Meeting of Japan Pancreas Society (JPS) in Kyoto in July 2022. During the meeting, presenters reported the current best multidisciplinary practices for LAPC, including preoperative modalities, best systemic treatment regimens and durations, procedures of conversion surgery with or without vascular resections, biomarkers, and genetic studies. It was unanimously agreed among the experts in this meeting that "cancer biology is surpassing locoregional anatomical resectability" in the era of effective multiagent treatment. The biology of pancreatic cancer has yet to be further elucidated, and we believe it is essential to improve the treatment outcomes of LAPC patients through continued efforts from each institution and more international collaboration. This article summarizes the agreement during the discussion amongst the experts in the meeting. We hope that this will serve as a foundation for future international collaboration and recommendations for future guidelines.

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.

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.

New criteria of resectability for pancreatic cancer: A position paper by the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS)

The symposium "New criteria of resectability for pancreatic cancer" was held during the 33nd meeting of the Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) in 2021 to discuss the potential modifications that could be made in the current resectability classification. The meeting focused on setting the foundation for developing a new prognosis-based resectability classification that is based on the tumor biology and the response to neoadjuvant treatment (NAT). The symposium included selected experts from Western and Eastern high-volume centers who have discussed their concept of resectability status through published literature. During the symposium, presenters reported new resectability classifications from their respective institutions based on tumor biology, conditional status, pathology, and genetics, in addition to anatomical tumor involvement. Interestingly, experts from all the centers reached the agreement that anatomy alone is insufficient to define resectability in the current era of effective NAT. On behalf of the JSHBPS, we would like to summarize the content of the conference in this position paper. We also invite global experts as internal reviewers of this paper for intercontinental cooperation in creating an up-to-date, prognosis-based resectability classification that reflects the trends of contemporary clinical practice.

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.

Defining the Optimal Method for Measuring Metabolic Tumor Volume on Preoperative 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography as a Prognostic Predictor in Patients With Pancreatic Ductal Adenocarcinoma

Objectives

Metabolic tumor volume (MTV) on ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) is a promising prognostic predictor in pancreatic ductal adenocarcinoma (PDAC). However, the optimal segmentation method and threshold value to determine MTV for PDAC are still unclear. We explored the optimal method and threshold value for the prognostic value of MTV measured on pre-treatment ¹⁸F-FDG-PET/CT.

Methods

Seventy-three patients with resected PDAC who underwent ¹⁸F FDG-PET/CT before surgical resection were enrolled. MTV values of the tumor were measured on FDG-PET/CT by the two fixed-threshold methods using threshold values as 2.0, 2.5, 3.0, and 3.5 for the absolute method and 35%, 40%, 42%, 45%, and 50% for the relative method. Receiver operating characteristic curve analysis for prediction of 1-year survival rates was conducted for determining the optimal threshold values, and we selected the optimal method and threshold value considering area under the curve. The prognostic values of each FDG-PET/CT parameter for disease-specific survival and recurrence-free survival were assessed with Kaplan–Meier method and Cox proportional hazard models.

Results

In receiver operating characteristic curve analysis, MTV by the fixed-absolute threshold method based on a threshold value of 3.5 (MTV3.5) performed best in our study with area under the curve 0.724, sensitivity of 65%, and specificity of 75%. In univariate and multivariate analyses, MTV3.5 was significantly associated with disease-specific and recurrence-free survival.

Conclusions

MTV3.5 by absolute threshold on pre-treatment FDG-PET/CT was the best independent prognostic predictor in resectable PDAC compared with other absolute threshold values and relative threshold values.

Preceding Systemic Chemotherapy for Patients with Pancreatic Ductal Adenocarcinoma with Positive Peritoneal Cytology Provides Survival Benefit Compared with Up-Front Surgery

BACKGROUND

The significance of surgical resection in pancreatic ductal adenocarcinoma (PDAC) with positive peritoneal cytology (PPC) is controversial. This study aimed to evaluate whether preceding chemotherapy could be beneficial for patients with PDAC with PPC.

METHODS

Between 2017 and 2019, 34 consecutive PDAC patients diagnosed with PPC without distant metastasis were retrospectively reviewed. Twenty-three patients did not receive neoadjuvant treatment (NAT) and 11 received NAT. All patients received systemic chemotherapy after PPC was confirmed, and they underwent surgical resection if PPC turned negative. The treatment course, ratio of conversion surgery (CS), and prognosis were evaluated. Moreover, the prognosis of PPC patients who underwent up-front surgery without NAT between 2003 and 2016 was analyzed as a comparative cohort.

RESULTS

The median survival time (MST) of the patients without NAT was 31.4 months. CS was performed in 52.2% of the patients. Patients who underwent CS had better prognoses than those who did not undergo CS (p = 0.005). The CS rate was significantly higher in resectable PDAC (78.5%) than in borderline/unresectable PDAC (11.1%) (p = 0.002). The prognosis of patients with resectable PDAC was improved with preceding chemotherapy compared with up-front surgery (MST 13.0 months; p = 0.016). After NAT, the CS rate was low (27.3%), and the MST was only 14.1 months.

CONCLUSIONS

As an initial treatment for PDAC patients with PPC, chemotherapy may lead to a favorable prognosis. Especially, resectable PDAC is associated with a greater chance of improved prognosis. Future studies are required to ascertain whether up-front surgery or preceding chemotherapy should be performed for these patients.

Essential updates 2018/2019: Current topics in the surgical treatment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is highly malignant. While cancers in other organs have shown clear improvements in 5-year survival, the 5-year survival rate of pancreatic cancer is approximately 10%. Early relapse and metastasis are not uncommon, making it difficult to achieve an acceptable prognosis even after complete surgical resection of the pancreas. Studies have been performed on various treatments to improve the prognosis of PDAC, and multidisciplinary approaches including non-surgical treatments have led to gradual improvement. In the present literature review, we have described the significance of anatomical and biological resectability criteria, the concept of R0 resection in surgical treatment, the feasibility of minimally invasive surgery, the remarkable development of perioperative chemotherapy, the effectiveness of conversion surgery for unresectable PDAC, and ongoing challenges in PDAC treatment. We also provide an essential update on these subjects by focusing on recent trends and topics.

Prognostic value of FDG-PET radiomics with machine learning in pancreatic cancer

Patients with pancreatic cancer have a poor prognosis, therefore identifying particular tumor characteristics associated with prognosis is important. This study aims to investigate the utility of radiomics with machine learning using 18F-fluorodeoxyglucose (FDG)-PET in patients with pancreatic cancer. We enrolled 161 patients with pancreatic cancer underwent pretreatment FDG-PET/CT. The area of the primary tumor was semi-automatically contoured with a threshold of 40% of the maximum standardized uptake value, and 42 PET features were extracted. To identify relevant PET parameters for predicting 1-year survival, Gini index was measured using random forest (RF) classifier. Twenty-three patients were censored within 1 year of follow-up, and the remaining 138 patients were used for the analysis. Among the PET parameters, 10 features showed statistical significance for predicting overall survival. Multivariate analysis using Cox HR regression revealed gray-level zone length matrix (GLZLM) gray-level non-uniformity (GLNU) as the only PET parameter showing statistical significance. In RF model, GLZLM GLNU was the most relevant factor for predicting 1-year survival, followed by total lesion glycolysis (TLG). The combination of GLZLM GLNU and TLG stratified patients into three groups according to risk of poor prognosis. Radiomics with machine learning using FDG-PET in patients with pancreatic cancer provided useful prognostic information.

The Role of Positron Emission Tomography in Pancreatic Cancer and Gallbladder Cancer

18F-FDG-PET is complementary to conventional imaging in patients with clinical suspicion for exocrine pancreatic malignancies. It has similar if not superior sensitivity and specificity for detection of cancer, and when combined with contrast enhanced anatomic imaging of the abdomen, can improve diagnostic accuracy and aid in staging, assessment for resectability, radiation therapy planning, and prognostication. Various metabolic pathways affect FDG uptake in pancreatic ductal adenocarcinoma. The degree of uptake reflects histopathology, aggressiveness, metastatic potential, and metabolic profile of malignant cell and their interaction with cancer stroma. After treatment, FDG-PET is useful for detection of residual or recurrent cancer and can be used to assess and monitor response to therapy in unresectable or metastatic disease. The degree and pattern of uptake combined with other imaging features are useful in characterization of incidental pancreatic lesions and benign processes such as inflammation. Several novel PET radiopharmaceuticals have been developed to improve detection and management of pancreatic cancer. Gallbladder carcinoma is typically FDG avid and when anatomic imaging is equivocal PET can be used to assess metastatic involvement with high specificity and inform subsequent management.

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.

An integrated analysis of host- and tumor-derived markers for predicting high-grade dysplasia and associated invasive carcinoma of intraductal papillary mucinous neoplasms of the pancreas

PURPOSE

To clarify the usefulness of cancer-related inflammation, hypermetabolism, and subsequent host malnutrition biomarkers for predicting the histological grades of intraductal papillary mucinous neoplasms of the pancreas (IPMNs).

METHODS

The systemic immune-inflammation index (SII), prognostic nutritional index (PNI), and maximum standardized uptake value (SUVmax) on fluorodeoxyglucose-positron emission tomography were compared across 171 resected IPMN cases of different histological grades. The diagnostic performance of each marker and of their combinations for predicting IPMN with high-grade dysplasia (HGD)/associated invasive carcinoma (INV) was also tested.

RESULTS

Of the 171 IPMNs, the IPMN cases with HGD showed significantly higher values of SII (median 406 vs. 340; P = 0.041) and SUVmax (median 2.5 vs. 2.0; P = 0.001) than those with low-grade dysplasia (LGD). On a multivariate analysis, the SII and SUVmax were both independent markers for predicting HGD/INV. A combination analysis including the tumor- and host-derived markers in combination with imaging findings showed an improved diagnostic performance (area under the curve 0.824; sensitivity 75.9%; specificity 80.0%).

CONCLUSIONS

The combination of multiple markers of host-derived inflammation and tumor-derived focal hypermetabolism can serve as a predictor for the presence of HGD/INV.

Early recurrence detected by 18F-FDG PET/CT in patients with resected pancreatic ductal adenocarcinoma

F-fluoro-2-deoxy-D-glucose positron emission tomography integrated with computed tomography (F-FDG PET/CT) has been proved to be practical in detecting occult malignant lesions. However, the evidence of its utility in detecting early recurrence after resection of pancreatic ductal adenocarcinoma (PDAC) is lacking. Therefore, the primary aim of the present study is to evaluate the diagnostic value of F-FDG PET/CT in the early postoperative period after radical resection of PDAC.This retrospective study included 32 patients who had F-FDG PET/CT scan within 6 months after radical resection of PDAC between January 2010 and December 2018.In total, 10 positive PET results were found at surgical margins of remnant pancreas, 12 at locoregional lymph nodes, 5 at distant areas, with the corresponding mean maximum standard uptake value (SUVmax) of 5.8 ± 1.1, 5.9 ± 0.9, and 6.4 ± 0.7, respectively. The median follow-up time was 23.5 months (range: 8-75 months), and the median survival time was 39.5 months (95% confidence interval: 14.6-64.4 months) for the entire cohort. Patients with positive PET findings at either locoregional lymph nodes or distant areas obtained significantly poorer overall survival (OS) than those without increased FDG uptake at the corresponding areas (P = .003 and P < .001, respectively). Whereas comparisons of OS between patients with or without increased FDG uptake at the surgical margin of remnant pancreas presented no statistically difference (P = .742).The early application of F-FDG PET/CT after radical resection of PDAC could stratify the prognosis of patients well by detecting occult early recurrence at locoregional lymph nodes and distant areas efficiently.

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.

Lung recurrence and its therapeutic strategy in patients with pancreatic cancer

BACKGROUND

/Objectives: The lung is a major metastatic site of pancreatic cancer (PC). We aimed to assess the features and prognosis of patients with PC according to the recurrence pattern and the effect of resection of recurrent lung lesion.

METHODS

We enrolled 168 PC patients who had undergone macroscopically curative resection. All resected lung tumors were evaluated immunohistochemically for expressions of thyroid transcription factor-1 (TTF-1) and napsin A.

RESULTS

The most common site of first recurrence was the liver and local site, followed by the lung, peritoneum, and lymph node. Lung recurrence was observed significantly later than was liver recurrence. The median survival time (MST) after recurrence in patients with first recurrence in the lung was significantly longer than MST in patients with first recurrence in the liver (15.2 months vs 5.2 months, p = 0.039). Seven patients with lung recurrence underwent resection of the recurrent lesion. Surgical resection of single metastasis limited to the lung showed favorable overall survival after recurrence (MST = 36.5 months). Patients with single metastasis limited to the lung showed significantly lower value of FDG-PET SUVmax of the primary pancreatic tumor.

CONCLUSIONS

Patients with first recurrence in the lung showed better prognosis than did patients with first recurrence in the liver. Single metastasis limited to the lung could benefit from surgical resection and was significantly associated with lower FDG-PET SUVmax of the primary pancreatic tumor.

Prognostic indicators in pancreatic cancer patients undergoing total pancreatectomy

PURPOSE

To evaluate the long-term outcomes of total pancreatectomy in a modern cohort of pancreatic cancer patients and to establish whether any factors identified prior to pancreatic resection were related to poor survival.

METHODS

We analyzed, retrospectively, patients who underwent total pancreatectomy for pancreatic cancer between 2007 and 2016. The short- and long-term outcomes were investigated and Cox regression analysis was used to evaluate the prognostic factors identified before resection.

RESULTS

The subjects were 49 patients with a mean age of 65 years, who underwent total pancreatectomy in our hospital during the study period. Peritoneal washing cytology was performed in 48 patients, with positive results in 4 (8.3%). There was no 30-day mortality. The median overall survival was 22.5 months, with a 5-year survival rate of 28.5%. Univariate analyses of the pre-resection variables revealed that overall survival was associated with tumor location, resectability classification, maximum standardized uptake value of positron emission tomography, the preoperative carbohydrate antigen 19-9 level, and peritoneal washing cytology status. Multivariate analysis revealed that positive peritoneal washing cytology status and the maximum standardized uptake value were independent predictors of poor survival.

CONCLUSION

Total pancreatectomy for pancreatic cancer is appropriate for selected patients, but peritoneal washing cytology and positron emission tomography should be performed preoperatively.

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.

Meta-analysis of recurrence pattern after resection for pancreatic cancer

Background

Initial recurrence mapping of resected pancreatic ductal adenocarcinoma (PDAC) could help in stratifying patient subpopulations for optimal postoperative follow-up. The aim of this systematic review and meta-analysis was to investigate the initial recurrence patterns of PDAC and to correlate them with clinicopathological factors.

Methods

MEDLINE and Web of Science databases were searched systematically for studies reporting first recurrence patterns after PDAC resection. Data were extracted from the studies selected for inclusion. Pooled odds ratios (ORs) and 95 per cent confidence intervals were calculated to determine the clinicopathological factors related to the recurrence sites. The weighted average of median overall survival was calculated.

Results

Eighty-nine studies with 17 313 patients undergoing PDAC resection were included. The weighted median rates of initial recurrence were 20·8 per cent for locoregional sites, 26·5 per cent for liver, 11·4 per cent for lung and 13·5 per cent for peritoneal dissemination. The weighted median overall survival times were 19·8 months for locoregional recurrence, 15·0 months for liver recurrence, 30·4 months for lung recurrence and 14·1 months for peritoneal dissemination. Meta-analysis revealed that R1 (direct) resection (OR 2·21, 95 per cent c.i. 1·12 to 4·35), perineural invasion (OR 5·19, 2·79 to 9·64) and positive peritoneal lavage cytology (OR 5·29, 3·03 to 9·25) were significantly associated with peritoneal dissemination as initial recurrence site. Low grade of tumour differentiation was significantly associated with liver recurrence (OR 4·15, 1·71 to 10·07).

Conclusion

Risk factors for recurrence patterns after surgery could be considered for specific surveillance and treatments for patients with pancreatic cancer.

Significance of 18F-Fluorodeoxyglucose (FDG) Uptake in Response to Chemoradiotherapy for Pancreatic Cancer

BACKGROUND

A metabolic shift to glycolysis is reportedly involved in radioresistance. We examined whether pretreatment 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), which can detect enhanced glucose uptake, was able to predict the therapeutic response to chemoradiotherapy (CRT) in patients with pancreatic cancer (PC).

METHODS

Of 125 PC patients (75 unresectable and 50 borderline resectable), 37 and 26 underwent induction chemotherapy before CRT and surgical resection after CRT, respectively. FDG-PET was performed at three different institutions.

RESULTS

Of the 88 patients who underwent upfront CRT, 31 (35%), 34 (39%), and 23 (26%) showed a partial response (PR), stable disease, and progressive disease, respectively. The tumor PR rate was an independent factor associated with longer overall survival (OS) on multivariate analysis. We evaluated the optimal cut-off of maximum standardized uptake values (SUVmax) at initial diagnosis to detect the tumor PR rate at the three institutions separately. The SUVmax was independently associated with tumor response rate on multivariate analysis. In the low SUVmax group, induction chemotherapy had no significant impact on OS. In contrast, induction chemotherapy was significantly associated with longer OS in the high SUVmax group.

CONCLUSIONS

FDG-PET SUVmax was significantly associated with the therapeutic response to CRT in PC patients. Moreover, induction chemotherapy may improve the prognosis of patients with a high SUVmax tumor.