Elevated tumor-to-liver standardized uptake value ratio (TLR) from preoperative 18F-FDG PET/CT predicts poor prognosis of patients with clear cell renal cell carcinoma after nephrectomy

Diagnostic and prognostic role of 18F-FDG PET/CT for sarcomatoid differentiation in renal cell carcinoma

BACKGROUND

Sarcomatoid differentiation is an invasive dedifferentiated feature of tumor and associated with poor prognosis in renal cell carcinoma (RCC) patients. This study aimed to evaluate the utility of 18F-FDG PET/CT in predicting sarcomatoid differentiation in RCC and its potential prognostic value.

RESULTS

This retrospective study assessed newly diagnosed sarcomatoid differentiation renal cell carcinoma (SDRCC) patients who were staged using 18F-FDG PET/CT. Patients were categorized into high-grade sarcomatoid differentiation RCC (HG-SDRCC), low-grade sarcomatoid differentiation RCC (LG-SDRCC), and non-sarcomatoid differentiation RCC (non-SDRCC). The maximum standardized uptake value (SUVmax), mean standardized uptake value (SUVmean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were compared. Overall survival (OS) and disease-free survival (DFS) were analyzed. SUVmax, MTV, TLG, and SUVmean values were significantly higher in SDRCC compared to non-SDRCC (P < 0.05). Additionally, SUVmax, TLG, and SUVmean were significantly higher in HG-SDRCC compared to non-HG-SDRCC (P < 0.05). ROC curves revealed that SUVmax and SUVmean were effective for distinguishing HG-SDRCC from non-HG-SDRCC. The log-rank test identified SUVmax > 11, MTV > 95, TLG > 500, SUVmean > 5.2, invasion of peripheral tissue and/or organs, and metastasis as risk factors for SDRCC patients. Multivariate Cox proportional hazards model analyses indicated that TLG > 500 was a risk factor for poor DFS, while SUVmax > 11 and SUVmean > 5.2 were risk factors for poor OS.

CONCLUSIONS

18F-FDG PET/CT can effectively differentiate HG-SDRCC with more aggressive malignancy. The prognostic model developed in this study demonstrates that metabolic parameters, particularly TLG for DFS and SUVmax/SUVmean for OS, serve as more robust predictors of patient outcomes than the degree of sarcomatoid differentiation.

The Utility of 18F-FDG PET/CT in Detecting Multiple Metastases in Papillary Renal Cell Carcinoma

The diagnostic performance of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for primary kidney tumors is limited. Nevertheless, 18F-FDG PET/CT is valuable for staging renal cell carcinoma (RCC) when suspected metastases coexist, as one-third of patients with RCC have distant metastases upon diagnosis. Herein, we present a 53-year-old male patient with extensive 18F-FDG-avid metastatic lesions and an 18F-FDG-avid renal mass, which later revealed RCC.

Prognostic value of TLR from FDG PET/CT in patients with margin-negative stage IB and IIA non-small cell lung cancer

OBJECTIVES

To evaluate the prognostic value of TLR from PET/CT in patients with resection margin-negative stage IB and IIA non-small cell lung cancer (NSCLC) and compare high-risk factors necessitating adjuvant treatment (AT).

METHODS

Consecutive FDG PET/CT scans performed for the initial staging of NSCLC stage IB and IIA were retrospectively reviewed. The maximum standardized uptake value (SUVmax) of the primary tumor and mean SUV of the liver were acquired. The tumor-to-liver SUV ratio (TLR) was also calculated. Charts were reviewed for basic patient characteristics and high-risk factors for considering AT (poor differentiation, visceral pleura invasion, vascular invasion, tumors > 4 cm, and wedge resection). Statistical analysis was performed using Cox regression analysis and the Kaplan-Meier method.

RESULTS

Of the 112 patients included, 15 (13.4%) died, with a median overall survival (OS) of 43.8 months. Twenty-two patients (19.6%) exhibited recurrence, with median disease-free survival (DFS) of 36.0 months. In univariable analysis, pathology, poor differentiation, and TLR were associated with shorter DFS and OS. In multivariable analysis, TLR (hazard ratio [HR] = 1.263, p = 0.008) and differentiation (HR = 3.087, p = 0.012) were associated with shorter DFS. Also, TLR (HR = 1.422, p < 0.001) was associated with shorter OS.

CONCLUSION

TLR from FDG PET/CT was an independent prognostic factor for recurrence and survival. PET parameters constitute risk factors for consideration in the decision-making for AT in margin-negative stage IB and IIA NSCLC.

CLINICAL RELEVANCE STATEMENT

In this study, TLR from FDG PET/CT was an independent prognostic factor in stage IB-IIA non-small cell cancer patients. Although additional validation studies are warranted, TLR has the potential to be used to determine the need for adjuvant therapy.

KEY POINTS

• High TLR is an independent poor prognostic factor in stage IB-IIA NSCLC. • Adjuvant treatment should be considered in patients with high TLR following complete tumor resection.

Low TLR and PSMA-TV predict biochemical response to abiraterone acetate in metastatic prostate cancer patients developing castration resistance after chemohormonal therapy at hormone-sensitive stage

OBJECTIVE

To explore whether 68Ga-PSMA-11 PET/CT-derived parameters could predict biochemical response to abiraterone acetate (AA) treatment and prognosis in metastatic prostate cancer patients developing castration resistance after chemohormonal therapy at hormone-sensitive stage.

METHODS

The clinicopathologic data of 106 mCRPC cases receiving AA treatment were retrospectively analyzed. Logistic regression analysis was used to determine the independent predictors of biochemical response to AA treatment. Cox analyses were applied to investigate the independent prognostic factors for time to biochemical progression (TTBP) and radiological progression-free survival (rPFS). Survival analysis and ROC curve were also used.

RESULTS

Multivariable Logistic analysis demonstrated that prior ADT duration ≥ 12 months, low prostate specific membrane antigen receptor-expressing tumor volume (PSMA-TV), low tumor to liver ratio (TLR) were independent predictors of biochemical response to AA treatment. Multivariate Cox analysis demonstrated that low PSMA-TV and low TLR were independent prognostic factors of longer TTBP and rPFS. The TTBP and rPFS of patients with higher PSMA-TV or TLR were significantly decreased compared with that of patients with lower PSMA-TV and TLR. The area under ROC curve (AUC) of combining ADT duration, PSMA-TV and TLR was 0.82 for predicting biochemical response to AA, which was significantly increased compared with that of other 68Ga-PSMA-11 PET/CT-derived parameters alone.

CONCLUSIONS

Low PSMA-TV, low TLR were vital independent predictors of biochemical response to AA treatment and were associated with preferable prognosis in mCRPC patients. Combining ADT duration, PSMA-TV and TLR performed well in distinguishing AA responders from non-responders in mCRPC patients.

Diagnostic performance and prognostic value of preoperative 18F-FDG PET/CT in renal cell carcinoma patients with venous tumor thrombus

Background

To observe the diagnostic efficacy of preoperative fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) upon venous tumor thrombus (VTT) in patients with renal cell carcinoma (RCC), and investigate the prognostic value of imaging parameters integrated with clinicopathological characteristics in patients with VTT after nephrectomy with tumor thrombectomy.

Methods

Patients with newly diagnosed RCC who underwent 18F-FDG PET/CT were reviewed retrospectively. The diagnostic efficacy of 18F-FDG PET/CT in VTT was analyzed. Logistic regression analysis was carried out to identify the clinical variables and PET/CT variables (including maximum standardized uptake value (SUVmax) of primary tumor, VTT SUVmax and primary tumor size) for differentiating early VTT (Mayo 0-II) from advanced VTT (Mayo III-IV). Cox proportional hazard analyses were used to evaluate clinicopathological factors and PET/CT factors (including distant metastasis, primary tumor SUVmax, VTT SUVmax and primary tumor size) for disease-free survival (DFS) in patients with VTT after operation.

Results

A total of 174 eligible patients were included in this study, including 114 men (65.5%) and 60 women (34.5%), with a median age of 58 years (range, 16–81 years). The distribution of pathological tumor stage (T stage) was 56 (T1), 17 (T2), 95 (T3), and 6 cases (T4), respectively. According to WHO/ISUP grade, except for 4 cases of chromophobe cell RCC, there were 14 patients (8.0%) of grade 1, 59 patients (33.9%) of grade 2, 74 patients (42.5%) of grade 3 and 23 patients (13.2%) of grade 4. The median maximum diameter of the primary tumor on PET/CT was 7.3 cm (5.0–9.5 cm). The distal metastasis was observed in 46 patients (26.4%). Sixty-one cases (35.1%) were confirmed with VTT by pathology. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of 18F-FDG PET/CT imaging were 96.7, 99.1, 98.3, 98.3, and 98.2%, in detecting VTT, respectively, and 70.0, 100.0, 94.9, 100.0, and 94.2%, in evaluating the level of VTT, respectively. Elevated VTT SUVmax (≥5.20) could significantly distinguish the early VTT group and advanced VTT group (P = 0.010). In the prognosis analysis, elevated VTT SUVmax (≥4.30) (P = 0.018, HR 3.123, 95% CI 1.212–8.044) and distant metastasis (P = 0.013, HR 3.344, 95% CI 1.293–8.649) were significantly independent predictors for DFS.

Conclusion

Preoperative 18F-FDG PET/CT has a high diagnostic efficacy in detecting VTT and evaluating its level in RCC patients. Those patients with elevated VTT SUVmax should be carefully monitored to detect the possibility of disease progression after operation.

FDG-PET Positivity and Overall Survival in Renal Cell Carcinoma

This cohort study examines positron emission tomography in renal cell carcinoma and its association with overall survival among adults.

Metabolic tumour volume on 18F-FDG PET/CT predicts extended pathological T stages in patients with renal cell carcinoma at staging

We evaluated the predictive value of ¹⁸F-fluorodeoxyglucose (FDG) uptake on positron emission tomography/CT (PET/CT) for extended pathological T (pT) stages (≥ pT3a) in Renal cell carcinoma (RCC) patients at staging. Thirty-eight RCC patients who underwent ¹⁸F-FDG PET/CT at staging, followed by radical nephrectomy between September 2016 and September 2018, were included in this prospective study. Patients were classified into two groups (limited pT stage: stage T1/2, n = 17; extended pT stage: T3/4, n = 21). Univariate and multivariate logistic regression analyses were performed to identify clinicopathological and metabolic variables to predict extended pT stages. ¹⁸F-FDG metabolic parameters were compared in relation to International Society of Urological Pathology (ISUP) grade and lymphovascular invasion (LVI). In univariate analysis, maximum standardised uptake value, metabolic tumour volume (MTV), and ISUP grade were significant. In multivariate analysis, MTV was the only significant factor of extended pT stages. With a cut-off MTV of 21.2, an area under the curve was 0.944, which was higher than 0.824 for clinical T stages (p = 0.037). In addition, high MTV, but not tumour size, was significantly correlated with aggressive pathologic features (ISUP grade and LVI). High glycolytic tumour volume on ¹⁸F-FDG PET/CT in RCC patients at staging is predictive of extended pT stages which could aid decision-making regarding the best type of surgery.

Noninvasive evaluation of tumor immune microenvironment in patients with clear cell renal cell carcinoma using metabolic parameter from preoperative 2-[18F]FDG PET/CT

PURPOSE

Nowadays, it is necessary to explore effective biomarkers associated with tumor immune microenvironment (TIME) noninvasively. Here, we investigated whether the metabolic parameter from preoperative 2-[¹⁸F]FDG PET/CT could provide information related to TIME in patients with clear cell renal cell carcinoma (ccRCC).

METHODS

Ninety patients with newly diagnosed ccRCC who underwent 2-[¹⁸F]FDG PET/CT prior to surgery were retrospectively reviewed. The immunological features included tumor-infiltrating lymphocytes (TILs) density, programmed death-ligand 1 (PD-L1) expression, and tumor immune microenvironment types (TIMTs). TIMTs were classified as TIMT I (positive PD-L1 and high TILs), TIMT II (negative PD-L1 and low TILs), TIMT III (positive PD-L1 and low TILs), and TIMT IV (negative PD-L1 and high TILs). The relationship between maximum standardized uptake value (SUVmax) in the primary lesion from 2-[¹⁸F]FDG PET/CT and immunological features was analyzed. Cox proportional hazards analyses were performed to identify the prognostic factors for disease-free survival (DFS) after nephrectomy.

RESULTS

Tumors with high TILs infiltration showed remarkable correlation with elevated SUVmax and aggressive clinicopathological characteristics, such as high World Health Organization/International Society of Urological Pathology (WHO/ISUP) grade. PD-L1 expression on tumor cells was positively associated with WHO/ISUP grade and negatively correlated with body mass index (BMI). However, no correlation was observed between SUVmax and PD-L1 expression, regardless of its spatial tissue distribution. SUVmax of TIMT I and IV was higher than that of TIMT II, but there was remarkable difference merely between TIMT II and IV. In multivariate analysis, SUVmax (P = 0.022, HR 3.120, 95% CI 1.175-8.284) and WHO/ISUP grade (P = 0.046, HR 2.613, 95% CI 1.017-6.710) were the significant prognostic factors for DFS. Six cases (16.2%) with normal SUVmax showed disease progression, while 25 cases (71.4%) with elevated SUVmax experienced disease progression. Conversely, the immunological features held no prognostic value.

CONCLUSIONS

Our findings demonstrated that 2-[¹⁸F]FDG PET/CT could provide metabolic information of TIME for ccRCC patients and develop image-guided therapeutic strategies accordingly. Patients with elevated preoperative SUVmax should be seriously considered, and perioperative immunotherapy might be beneficial for them.