Prognostic significance of standardized uptake value on preoperative ¹⁸F-FDG PET/CT in patients with ampullary adenocarcinoma

Prognostic Significance of 18 F-FDG PET/CT Radiomics in Patients With Resectable Pancreatic Ductal Adenocarcinoma Undergoing Curative Surgery

PURPOSE

This study aimed to investigate the prognostic significance of PET/CT radiomics to predict overall survival (OS) in patients with resectable pancreatic ductal adenocarcinoma (PDAC).

METHODS

We enrolled 627 patients with resectable PDAC who underwent preoperative 18 F-FDG PET/CT and subsequent curative surgery. Radiomics analysis of the PET/CT images for the primary tumor was performed using the Chang-Gung Image Texture Analysis toolbox. Radiomics features were subjected to least absolute shrinkage and selection operator (LASSO) regression to select the most valuable imaging features of OS. The prognostic significance was evaluated by Cox proportional hazards regression analysis. Conventional PET parameters and LASSO score were assessed as predictive factors for OS by time-dependent receiver operating characteristic curve analysis.

RESULTS

During a mean follow-up of 28.8 months, 378 patients (60.3%) died. In the multivariable Cox regression analysis, tumor differentiation, resection margin status, tumor stage, and LASSO score were independent prognostic factors for OS (HR, 1.753, 1.669, 2.655, and 2.946; all P < 0.001, respectively). The time-dependent receiver operating characteristic curve analysis showed that the LASSO score had better predictive performance for OS than conventional PET parameters.

CONCLUSIONS

The LASSO score using the 18 F-FDG PET/CT radiomics of the primary tumor was the independent prognostic factor for predicting OS in patients with resectable PDAC and may be helpful in determining therapeutic and follow-up plans for these patients.

Predictive value of metabolic activity detected by pre-operative 18F FDG PET/CT in ampullary adenocarcinoma

In ampullary adenocarcinoma cases, the clinical effects of 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) have not yet been well-studied, unlike other prognostic factors that have been reported till date. This study aimed to investigate the clinical impact of maximum standardized uptake value (SUVmax) in predicting the prognosis of ampullary adenocarcinoma.Thirty-eight patients who underwent pre-operative 18F-FDG PET/CT and curative-intent resection of ampullary adenocarcinoma at Pusan National University Hospital (Pusan, South Korea) between 2008 and 2017 were retrospectively analyzed in this study. We evaluated the clinicopathologic outcomes according to the SUVmax using univariate and multivariate Cox proportional hazard regression analyses and receiver operating characteristic analysis to arrive at a cutoff value.Lymph node metastasis was detected in 9 patients, and 15 patients experienced a recurrence during the follow-up period. Among 38 patients, 33 showed an increased FDG uptake by the main tumor. SUVmax of 4.55 was selected as a significant independent predictive factor for patient survival along with poor tumor differentiation and high neutrophil-to-lymphocyte ratio in multivariate analysis (P = .016, hazard ratio = 5.040). Patients with SUVmax under 4.55 exhibited significantly longer overall survival than the rest (<4.55 vs ≥4.55), and the 5-year overall survival was 82.8% versus 57.4% (P = .049).SUVmax of 4.55 on 18F-FDG PET/CT could be a predictive factor for tumor biology and long-term survival in patients with ampullary adenocarcinoma. Nevertheless, considering the cost aspect and its limited prognostic effect, this study seems to require more patient and multicenter studies.

Efficacy and safety of adjuvant therapy after curative surgery for ampullary carcinoma: A systematic review and meta-analysis

BACKGROUND

Ampullary carcinoma patients require radical resection for optimal survival; however, the outcomes are often unsatisfactory. The utility of adjuvant therapy among such patients is unclear, probably owing to its potential side effects. Therefore, this study investigated the benefits and safety of adjuvant therapy in resected ampullary carcinoma.

METHODS

Cochrane, Embase, Medline, and PubMed databases were systematically searched for eligible studies, and those comparing adjuvant therapy and surgical treatment alone were included. Hazard ratios for survival outcomes and the number of adverse events for safety endpoints were extracted and subjected to pooled analyses through a random-effects model.

RESULTS

In total, 27 studies involving 3,538 patients were included. Adjuvant therapy was significantly associated with decreased mortality risk (hazard ratio, 0.58; 95% confidence interval 0.40-0.84), especially for chemoradiotherapy (hazard ratio, 0.42; 95% confidence interval 0.28-0.62). Furthermore, adjuvant therapy was significantly associated with increased overall survival among high-risk patients (hazard ratio, 0.63; 95% confidence interval 0.48-0.82) or those with the pancreaticobiliary subtype (hazard ratio, 0.53; 95% confidence interval 0.32-0.85). By contrast, adjuvant therapy was not associated with improved overall survival among low-risk patients (hazard ratio, 0.93; 95% confidence interval 0.52-1.68) or those with the intestinal subtype (hazard ratio, 1.06; 95% confidence interval 0.57-1.95). Regarding the safety of adjuvant therapy, no intervention-related mortality occurred, and severe adverse events were within the acceptable range (risk difference, 0.04; 95% confidence interval 0.01-0.08).

CONCLUSION

The present results suggest that adjuvant therapy is safe and extends survival in high-risk patients or those with the pancreaticobiliary subtype of ampullary carcinoma.

Preoperative 2-[18F]FDG PET-CT aids in the prognostic stratification for patients with primary ampullary carcinoma

OBJECTIVES

We sought to investigate whether preoperative dual-phase 2-[¹⁸F]FDG PET-CT identify predictors for poor survival in patients with ampullary carcinoma receiving pancreaticoduodenectomy.

METHODS

The preoperative PET-CT images of patients with resected ampullary carcinoma from June 2007 to July 2017 were analyzed. Survival curves were analyzed using the Kaplan-Meier method and compared with the log-rank test. Cox proportional hazard model was used to identify potential prognostic factors associated with disease-free survival (DFS) and overall survival (OS).

RESULTS

Fifty-four subjects (26 men, 28 women) were enrolled with a median tumor size of 20 mm. All patients were followed for a median period of 36.9 months with 3- and 5-year DFS of 50.3% and 44.2%, and OS of 77.0% and 68.2%, respectively. Parameters associated with DFS in multivariate analysis were lymphovascular invasion (hazard ratio [HR]: 9.45, p < 0.001), involved margin in pathology (HR: 7.67, p < 0.001), and tumor retention index (RI) from the dual-phase PET (HR: 2.41, p = 0.03), whereas involved margin (HR: 13.14, p < 0.001), post-recurrence chemotherapy (HR: 0.10, p < 0.001), and metabolic tumor volume (MTV) (HR: 4.62, p = 0.009) emerged as independent prognostic factors for OS.

CONCLUSIONS

Preoperative 2-[¹⁸F]FDG PET-CT offered independent prognostic biomarkers in patients with ampullary carcinoma receiving standard surgical resection.

KEY POINTS

• 2-[¹⁸F]FDG PET-CT offers good survival prediction before operation in primary malignant neoplasms at ampulla of Vater. • Dual-phase PET scan with bowel distention can better delineate Ampulla of Vater and characterize tumor physiology. • Preoperative risk stratification might aid in better treatment planning.

Intra-tumor metabolic heterogeneity of gastric cancer on 18F-FDG PETCT indicates patient survival outcomes

The present study aimed to investigate the prognostic value of intra-tumor metabolic heterogeneity on 2-[18F] Fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) for patients with gastric cancer. Fifty-five patients with advanced gastric cancer that had received neoadjuvant chemotherapy and radical surgery were included. Clinicopathological information, ¹⁸F-FDG PET/CT before chemotherapy, pathological response, recurrence or metastasis, progression-free survival (PFS), and overall survival (OS) of the patients were collected. The maximum, peak, and mean standardized uptake values (SUV_max, SUV_peak, and SUV_mean), tumor-to-liver ratio (TLR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on PET/CT were measured. Heterogeneity index-1 (HI-1) was calculated as SUV_mean divided by the standard deviation, and heterogeneity index-2 (HI-2) was evaluated through linear regressions of MTVs according to different SUV thresholds. Associations between these parameters and patient survival outcomes were analyzed. None of the parameters on PET were associated with tumor recurrence. Pathological responders had significantly smaller TLR, MTV and HI-2 values than non-responders (P = 0.017, 0.017 and 0.013, respectively). In multivariate analysis of PFS, only HI-2 was an independent factor (hazard ratio [HR] = 2.693, P = 0.005) after adjusting for clinical tumor-node-metastasis (TNM) stage. In multivariate analysis of OS, HI-2 was also an independent predictive factor (HR = 2.281, P = 0.009) after adjusting for tumor recurrence. Thus, HI-2 generated from baseline ¹⁸F-FDG PET/CT is significantly associated with survival of patients with gastric cancer. Preoperative assessment of HI-2 by ¹⁸F-FDG PET/CT might be promising to identify patients with poor prognosis.

Prognostic factors and benefits of adjuvant therapy for ampullary cancer following pancreatoduodenectomy: A systematic review and meta-analysis

Ampullary cancer is a relatively rare gastrointestinal malignancy. The purpose of this study was to evaluate prognostic factors for survival and assess the benefits of adjuvant therapy following pancreaticoduodenectomy for this entity. Medline and EMBASE databases were searched to identify eligible studies from January 2000 to August 2019. Review Manager 5.3 statistical software was used for meta-analysis. 71 studies met the inclusion criteria and were included in the analysis for a total of 8280 patients. The median (range) 5-year overall survival and disease-free survival rates were 58% (32-82%) and 51% (28-73%) respectively. In meta-analysis, age >65 years at diagnosis, tumor size >20 mm, poor differentiation, pancreaticobiliary histotype, pT3-4 stage disease, presence of metastatic lymph node, number of metastatic nodes, perineural invasion, lymphovascular invasion, vascular invasion, pancreatic invasion, and positive surgical margins were independently associated with worse overall survival, whereas adjuvant therapy was associated with improved overall survival. In summary, in patients with ampullary cancer undergoing pancreaticoduodenectomy, tumor factors are the main predictors of worse survival and adjuvant treatment confers a survival benefit.

Different biological behaviors in left-sided pancreatic cancer according to Yonsei criteria: Proposal of a modified Yonsei criteria score

BACKGROUND/OBJECTIVES

Our institutional experience has demonstrated that bloodless and margin-negative resection is the most potent prognostic factor in treating left-sided pancreatic cancer and we developed selection guideline. The Yonsei criteria (YC) is selection criteria for oncologically safe and effective resection of left-sided pancreatic cancer by a minimally invasive approach. In this study, we investigated whether left-sided pancreatic cancer with YC can be more individualized to predict long-term survival by using clinically and pathologically detectable parameters.

METHODS

From January 2000 to December 2015, 105 patients underwent distal pancreatectomy for left-sided pancreatic cancer. The medical records of the patients were retrospectively reviewed.

RESULTS

Among clinically and pathologically detectable parameters to predict tumor conditions, radiologically determined tumor size (p = 0.080) and SUVmax (p = 0.086) were identified as predictors of early tumor recurrence with marginal significance. Among them, 20% of the patients with YC were identified as having the most favoring tumor condition, with an modified YC score of 3. The patient group with the lowest mYC score was found to have a very long disease-free survival time, with a mean of 108 months, which was statistically different from those with other mYC scores (mYC score = 4, mean 47.1 months [95% CI: 27.8-69.5] vs. mYC score = 5, mean 36.7 months [95% CI: 12.7-60.7], vs. mYC score = 6, mean 10.7 months [95% CI: 3.9-17.4]).

CONCLUSIONS

Modified Yonsei criteria score can predict long-term survival in resected left-sided pancreatic cancer. And patients within YC with a mYC score = 3 could have a favorable survival outcome.

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.

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.