Fluorine-18-fluorodeoxyglucose uptake of bone marrow on PET/CT can predict prognosis in patients with colorectal cancer after curative surgical resection

Healthy tissue metabolism assessed by [18F]FDG PET/CT as a marker of prognosis and adverse events in advanced Hodgkin lymphoma patients

The aim of the study was to assess healthy tissue metabolism (HTM) using 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography/computed tomography (PET/CT) during chemotherapy in Hodgkin lymphoma (HL) and the association of HTM with baseline metabolic tumour volume (MTV), haematological parameters, adverse events (AEs), early response and progression-free survival (PFS). We retrospectively identified 200 patients with advanced HL from the RATHL trial with [18F]FDG-PET/CT before (PET0) and following 2 cycles of chemotherapy (PET2). [18F]FDG-uptake was measured in bone marrow (BM), spleen, liver and mediastinal blood pool (MBP). Deauville score (DS) 1-3 was used to classify responders and DS 4-5, non-responders. [18F]FDG-uptake decreased significantly in BM and spleen and increased in liver and MBP at PET2 (all p < 0.0001), but was not associated with MTV. Higher BM uptake at PET0 was associated with lower baseline haemoglobin and higher absolute neutrophil counts, platelets, and white blood cells. High BM, spleen, and liver uptake at PET0 was associated with neutropenia after cycles 1-2. BM uptake at PET0 was associated with treatment failure at PET2 and non-responders with higher BM uptake at PET2 had significantly inferior PFS (p = 0.023; hazard ratio = 2.31). Based on these results, we concluded that the change in HTM during chemotherapy was most likely a direct impact of chemotherapy rather than a change in MTV. BM uptake has prognostic value in HL.

Relationship of FDG PET/CT imaging features with tumor immune microenvironment and prognosis in colorectal cancer: a retrospective study

BACKGROUND

Imaging features of colorectal cancers on 2-deoxy-2-[18F]fluoro-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT) have been considered to be affected by tumor characteristics and tumor immune microenvironment. However, the relationship between PET/CT imaging features and immune reactions in tumor tissue has not yet been fully evaluated. This study investigated the association of FDG PET/CT imaging features in the tumor, bone marrow, and spleen with immunohistochemical results of cancer tissue and recurrence-free survival (RFS) in patients with colorectal cancer.

METHODS

A total of 119 patients with colorectal cancer who underwent FDG PET/CT for staging work-up and received curative surgical resection were retrospectively enrolled. From PET/CT images, 10 first-order imaging features of primary tumors, including intensity of FDG uptake, volumetric metabolic parameters, and metabolic heterogeneity parameters, as well as FDG uptake in the bone marrow and spleen were measured. The degrees of CD4+, CD8+, and CD163 + cell infiltration and interleukin-6 (IL-6) and matrix metalloproteinase-11 (MMP-11) expression were graded through immunohistochemical analysis of surgical specimens. The relationship between FDG PET/CT imaging features and immunohistochemical results was assessed, and prognostic significance of PET/CT imaging features in predicting RFS was evaluated.

RESULTS

Correlation analysis with immunohistochemistry findings showed that the degrees of CD4 + and CD163 + cell infiltration and IL-6 and MMP-11 expression were correlated with cancer imaging features on PET/CT. Patients with enhanced inflammatory response in cancer tissue demonstrated increased FDG uptake, volumetric metabolic parameters, and metabolic heterogeneity. FDG uptake in the bone marrow and spleen was positively correlated with the degree of CD163 + cell infiltration and IL-6 expression, respectively. In multivariate survival analysis, the coefficient of variation of FDG uptake in the tumor (p = 0.019; hazard ratio, 0.484 for 0.10 increase) and spleen-to-liver uptake ratio (p = 0.020; hazard ratio, 24.901 for 1.0 increase) were significant independent predictors of RFS.

CONCLUSIONS

The metabolic heterogeneity of tumors and FDG uptake in the spleen were correlated with tumor immune microenvironment and showed prognostic significance in predicting RFS in patients with colorectal cancer.

FDG-PET/CT is a powerful tool to predict and evaluate response to chimeric antigen receptor (CAR) T-cell therapy in Non-Hodgkin-Lymphoma (NHL)

Chimeric antigen receptor (CAR) T-cell therapy has dramatically shifted the landscape of treatment especially for Non-Hodgkin-Lymphoma (NHL). This study evaluates the role of fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) in NHL treated with CAR T-cell therapy concerning response assessment and prognosis.We evaluated 34 patients with NHL who received a CAR T-cell therapy between August 2019 and July 2022. All patients underwent a pre-therapeutic FDG-PET/CT (PET-0) 6 days prior and a post-therapeutic FDG-PET/CT (PET-1) 34 days after CAR T-cell therapy. Deauville score (DS) was used for evaluation of response to therapy and compared to a minimum follow-up of 5 months.19/34 (55.9%) patients achieved DS ≤ 3 on PET-1, the remaining 15 (44.1%) patients had DS > 3 on PET-1. 14/19 patients with DS ≤ 3 on PET-1 had no relapsed or refractory (r/r)-disease and were still alive at last follow-up. The other 5 patients had r/r-disease and 4 of these died. Except for two patients who had no r/r-disease, all other patients (13/15) with DS > 3 on PET-1 had r/r-disease and 12 of these subsequently died. Patients with DS ≤ 3 on PET-1 had significantly better progression free survival (PFS; HR: 5.7; p < 0.01) and overall survival (OS; HR: 5.0; p < 0.01) compared to patients with DS > 3 on PET-1. In addition, we demonstrated that patients with DS ≤ 4 on PET-0 tended to have longer PFS (HR: 3.6; p = 0.05).Early FDG-PET/CT using the established DS after CAR T-cell therapy is a powerful tool to evaluate response to therapy.

Prognostic value of 18F-fluorodeoxyglucose uptake in the bone marrow on pretreatment positron emission tomography/computed tomography in patients with esophageal cancer who underwent esophagectomy

BACKGROUND

Increased 18F-fluorodeoxyglucose (FDG) uptake in the bone marrow (BM) on positron emission tomography/computed tomography (PET/CT) clinically reflects increased BM metabolism owing to systemic inflammation, bacterial infection, anemia, and cytokine-producing tumors. The association between FDG uptake in the BM and prognosis after esophagectomy for esophageal cancer has not been investigated.

METHODS

This study included 651 patients who underwent PET/CT before any treatment and McKeown esophagectomy for esophageal cancer between June 2007 and August 2021. The pretreatment degree of FDG uptake in the BM was evaluated using a visual assessment criterion. Patients were divided into low- and high-FDG uptake groups. We retrospectively investigated whether the degree of FDG uptake in the BM was associated with clinicopathological and surgical backgrounds, blood parameters, and prognosis.

RESULTS

High FDG uptake in the BM was significantly associated with elevated white blood cell and neutrophil counts, increased C-reactive protein levels, decreased hemoglobin, serum albumin, and total cholesterol levels. High FDG uptake in the BM was an independent predictor of worse overall survival in clinical stages 0-II esophageal cancer (hazard ratio, 2.27; 95% confidence interval, 1.097-4.695; P = 0.027). Worse overall survival was also associated with advanced age, low American Society of Anesthesiologists physical status, an advanced clinical stage, and high intraoperative blood loss.

CONCLUSION

Increased FDG uptake in the BM on pretreatment PET/CT may be a surrogate indicator of various clinically disadvantageous backgrounds and may act as a predictor of poor prognosis after esophageal cancer surgery.

Whole body FDG PET/MR for progression free and overall survival prediction in patients with relapsed/refractory large B-cell lymphomas undergoing CAR T-cell therapy

BACKGROUND

To find semi-quantitative and quantitative Positron Emission Tomography/Magnetic Resonance (PET/MR) imaging metrics of both tumor and non-malignant lymphoid tissue (bone marrow and spleen) for Progression Free Survival (PFS) and Overall Survival (OS) prediction in patients with relapsed/refractory (r/r) large B-cell lymphoma (LBCL) undergoing Chimeric Antigen Receptor (CAR) T-cell therapy.

METHODS

A single-center prospective study of 16 r/r LBCL patients undergoing CD19-targeted CAR T-cell therapy. Whole body 18F-fluorodeoxyglucose (FDG) PET/MR imaging pre-therapy and 3 weeks post-therapy were followed by manual segmentation of tumors and lymphoid tissues. Semi-quantitative and quantitative metrics were extracted, and the metric-wise rate of change (Δ) between post-therapy and pre-therapy calculated. Tumor metrics included maximum Standardized Uptake Value (SUV_max), mean SUV (SUV_mean), Metabolic Tumor Volume (MTV), Tumor Lesion Glycolysis (TLG), structural volume (V), total structural tumor burden (V_total) and mean Apparent Diffusion Coefficient (ADC_mean). For lymphoid tissues, metrics extracted were SUV_mean, mean Fat Fraction (FF_mean) and ADC_mean for bone marrow, and SUV_mean, V and ADC_mean for spleen. Univariate Cox regression analysis tested the relationship between extracted metrics and PFS and OS. Survival curves were produced using Kaplan-Meier analysis and compared using the log-rank test, with the median used for dichotomization. Uncorrected p-values < 0.05 were considered statistically significant. Correction for multiple comparisons was performed, with a False Discovery Rate (FDR) < 0.05 considered statistically significant.

RESULTS

Pre-therapy (p < 0.05, FDR < 0.05) and Δ (p < 0.05, FDR > 0.05) total tumor burden structural and metabolic metrics were associated with PFS and/or OS. According to Kaplan-Meier analysis, a longer PFS was reached for patients with pre-therapy MTV ≤ 39.5 ml, ΔMTV≤1.35 and ΔTLG≤1.35. ΔSUV_max was associated with PFS (p < 0.05, FDR > 0.05), while ΔADC_mean was associated with both PFS and OS (p < 0.05, FDR > 0.05). ΔADC_mean > 0.92 gave longer PFS and OS in the Kaplan-Meier analysis. Pre-therapy bone marrow SUV_mean was associated with PFS (p < 0.05, FDR < 0.05) and OS (p < 0.05, FDR > 0.05). For bone marrow FDG uptake, patient stratification was possible pre-therapy (SUV_mean ≤ 1.8).

CONCLUSIONS

MTV, tumor ADC_mean and FDG uptake in bone marrow unaffected by tumor infiltration are possible PET/MR parameters for prediction of PFS and OS in r/r LBCL treated with CAR T-cells.

TRIAL REGISTRATION

EudraCT 2016-004043-36.

Prognostic Value of Bone Marrow Uptake Using 18F-FDG PET/CT Scans in Solid Neoplasms

BACKGROUND

Fluorine-18-fluorodeoxyglucose positron emission tomography/computerized tomography (18F-FDG PET/CT) uptake is known to increase in infective and inflammatory conditions. Systemic inflammation plays a role in oncologic prognosis. Consequently, bone marrow increased uptake in oncology patients could potentially depict the systemic cancer burden.

METHODS

A single institute cohort analysis and a systematic review were performed, evaluating the prognostic role of 18F-FDG uptake in the bone marrow in solid neoplasms before treatment. The cohort included 113 esophageal cancer patients (adenocarcinoma or squamous cell carcinoma). The systematic review was based on 18 studies evaluating solid neoplasms, including gynecological, lung, pleura, breast, pancreas, head and neck, esophagus, stomach, colorectal, and anus.

RESULTS

Bone marrow 18F-FDG uptake in esophageal cancer was not correlated with staging, pathological response, and survival. High bone marrow uptake was related to advanced staging in colorectal, head and neck, and breast cancer, but not in lung cancer. Bone marrow 18F-FDG uptake was significantly associated with survival rates for lung, head and neck, breast, gastric, colorectal, pancreatic, and gynecological neoplasms but was not significantly associated with survival in pediatric neuroblastoma and esophageal cancer.

CONCLUSION

18F-FDG bone marrow uptake in PET/CT has prognostic value in several solid neoplasms, including lung, gastric, colorectal, head and neck, breast, pancreas, and gynecological cancers. However, future studies are still needed to define the role of bone marrow role in cancer prognostication.

Correlation of bone marrow 2-deoxy-2-[ 18 F]fluoro-D-glucose uptake with systemic inflammation in patients with newly diagnosed endometrial cancer

OBJECTIVE

To clarify the relationship between 2-deoxy-2-[ 18 F]fluoro-D-glucose (FDG) uptake of bone marrow and systemic inflammation in patients with newly diagnosed endometrial cancer.

METHODS

A total of 119 patients with untreated endometrial cancer underwent FDG PET/computed tomography (CT). For bone marrow FDG uptake, the mean standardized uptake value (SUVmean) of the five vertebrae (T11-12 and L3-L5) was measured and averaged (bone marrow SUV). The bone marrow-to-liver ratio (BLR) was calculated by dividing the bone marrow SUV by the SUVmean of the normal liver. FDG PET parameters were correlated with white blood cell count, neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and C-reactive protein (CRP), albumin, and hemoglobin levels. They were also correlated with FIGO stage.

RESULTS

Bone marrow SUV and BLR showed significant positive correlations with white blood cell count, NLR, and CRP level and significant negative correlations with albumin level. BLR also showed a significant positive correlation with PLR. No significant differences in bone marrow SUV and BLR were apparent according to FIGO stage.

CONCLUSION

Pretreatment FDG PET/CT in patients with newly diagnosed endometrial cancer may provide information on host systemic inflammation as assessed by bone marrow FDG uptake.

Role of Positron Emission Tomography/Computed Tomography in Gastrointestinal Malignancies: A Brief Review and Pictorial Essay

Positron emission tomography/computed tomography (PET/CT) is increasingly becoming a mainstay in diagnosis and management of many malignant disorders. However, its role in the assessment of gastro-intestinal lesions is still evolving. The aim of this review was to demonstrate the areas, where PET/CT is impactful and where it has limitations. This will allow for us to reduce unnecessary investigations and develop methods to overcome the limitations.

Prognostic Value of Dual-Time-Point [18F]FDG PET/CT for Predicting Distant Metastasis after Treatment in Patients with Non-Small Cell Lung Cancer

This study aimed to evaluate the prognostic significance of 2-Deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) uptake in the bone marrow (BM) and primary tumors on dual-time-point (DTP) PET/CT for predicting progression-free survival (PFS) and distant metastasis-free survival (DMFS) in patients with non-small cell lung cancer (NSCLC). We retrospectively analyzed DTP [18F]FDG PET/CT images from 211 patients with NSCLC. The maximum standardized uptake value (SUV) of primary lung cancer and mean [18F]FDG uptake of the BM (BM SUV) were measured from early and delayed PET/CT images, and the percent changes in these parameters (∆maximum SUV and ∆BM SUV) were calculated. On multivariate survival analysis, the maximum SUV and BM SUV on both early and delayed PET/CT scans were significantly associated with PFS, while the ∆maximum SUV and ∆BM SUV failed to show statistical significance. For DMFS, the ∆maximum SUV and ∆BM SUV were independent predictors along with the TNM stage. Distant progression was observed only in 1.3% of patients with low ∆maximum SUV and ∆BM SUV, whereas 28.2% of patients with high ∆maximum SUV and ∆BM SUV experienced distant progression. The ∆maximum SUV and ∆BM SUV on DTP [18F]FDG PET/CT were significant independent predictors for DMFS in patients with NSCLC.

Prognostic Impact of Total Lesion Glycolysis (TLG) from Preoperative 18F-FDG PET/CT in Stage II/III Colorectal Adenocarcinoma: Extending the Value of PET/CT for Resectable Disease

We investigated the prognostic role of metabolic parameters from preoperative ¹⁸F-FDG PET/CT in stage II/III colorectal adenocarcinoma. A total of 327 stage II/III colorectal adenocarcinoma patients who underwent curative resection were included. The maximal standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were analyzed for optimal cut-offs and their effect on DFS. Differences in DFS rates and hazard ratios for DFS between cut-offs were statistically significant in SUVmax, MTV2.5, MTV3, TLG 2.5, TLG3, and TLG30%. Factors significantly related to DFS in univariate Cox regression were age, sex, stage, preoperative CEA, SUVmax, MTV2.5, MTV3, TLG2.5, TLG3, and TLG30%. Age, sex, preoperative CEA, and TLG2.5 (p = 0.009) sustained statistically significant difference in multivariate analysis. The 1-, 3-, and 5-year DFS rates for TLG2.5 ≤ 448.5 were 98.1%, 79.6%, and 74.8%, significantly higher than 78.4%, 68.5%, and 61.1% of TLG2.5 > 448.5, respectively (p = 0.012). TLG, a parameter indicating both the metabolic activity and metabolic volume, was the strongest predictor independently associated with DFS, among several PET parameters with statistical significance. These results suggest the potential prognostic value of preoperative ¹⁸F-FDG PET/CT in stage II/III resectable colorectal cancer.

Prognostic significance of imaging features of peritumoral adipose tissue in FDG PET/CT of patients with colorectal cancer

PURPOSE

This study investigated the relationship of imaging features of primary tumor and peritumoral VAT on PET/CT with histopathological findings of peritumoral VAT and recurrence-free survival (RFS) in patients with colorectal cancer.

METHODS

We retrospectively reviewed 133 patients diagnosed with colorectal cancer who underwent staging FDG PET/CT and received curative surgery. Histogram-based imaging features of primary tumor and peritumoral VAT were extracted from PET/CT images. Based on histopathological analysis of peritumoral VAT, the degree of CD4, CD8, and CD163 cell infiltration and the expression of matrix metalloproteinase-11 and interleukin 6 (IL-6) were graded. Differences in imaging parameters based on the histopathological results and the relationships between imaging features and RFS were assessed.

RESULTS

Mean CT-attenuation and SUV of peritumoral VAT showed significant positive correlation with CD163 cell infiltration and IL-6 expression of peritumoral VAT. Univariable survival analysis revealed significant correlation between RFS and the mean CT-attenuation, mean SUV, and first-order SUV entropy of peritumoral VAT (p < 0.05). Multivariable analysis indicated that mean SUV and SUV entropy of peritumoral VAT remained significant predictors of RFS after adjustment for age, sex, and T stage (p < 0.05).

CONCLUSION

FDG uptake of peritumoral VAT was significantly associated with inflammatory response in peritumoral VAT and was an independent predictor of RFS in colorectal cancer patients.

Predicting Survival in Patients with Pancreatic Cancer by Integrating Bone Marrow FDG Uptake and Radiomic Features of Primary Tumor in PET/CT

Simple Summary

FDG uptake of bone marrow (BM) is known to reflect the degree of host inflammatory response to cancer cells and showed significant association with survival in diverse kinds of cancers. The aim of this retrospective study was to evaluate the prognostic significance of FDG uptake of BM and to investigate whether integrating FDG uptake of BM and radiomic features of primary tumors could improve the prediction of overall survival (OS) in patients with pancreatic cancer. In multivariable survival analysis, along with total lesion glycolysis (TLG) and first-order entropy of primary tumor lesions, FDG uptake of BM was an independent predictor of OS. We designed a PET/CT scoring system based on the cumulative scores of tumor factors (TLG and first-order entropy) and host factors (FDG uptake of BM). This scoring system was able to stratify the patients with three distinct prognostic groups independent of clinical stage and treatment modality.

Abstract

The purpose of this study was to evaluate the prognostic significance of FDG uptake of bone marrow (BM SUV) and to investigate its role combined with radiomic features of primary tumors in improving the prediction of overall survival (OS) in patients with pancreatic cancer. We retrospectively enrolled 65 pancreatic cancer patients with staging FDG PET/CT. BM SUV and conventional imaging parameters of primary tumors including total lesion glycolysis (TLG) were measured. First-order and higher-order textural features of primary cancer were extracted using PET textural analysis. Associations of PET/CT parameters of bone marrow (BM) and primary cancer with OS were assessed. BM SUV as well as TLG and first-order entropy of pancreatic cancer were significant independent predictors of OS in multivariable analysis. A PET/CT scoring system based on the cumulative scores of these three independent predictors enabled patient stratification into three distinct prognostic groups. The scoring system yielded a good prognostic stratification based on subgroup analysis irrespective of tumor stage and treatment modality. BM SUV was an independent predictor of OS in pancreatic cancer patients. The PET/CT scoring system that integrated PET/CT parameters of primary tumors and BM can provide prognostic information in pancreatic cancer independent of tumor stage and treatment.

Prognostic significance of bone marrow and spleen 18F-FDG uptake in patients with colorectal cancer

Serum inflammatory markers are used in the prognostication of colorectal cancer (CRC); however, the corresponding role of positron emission tomography (PET)-derived inflammatory markers remains unclear. This study aimed to investigate the prognostic value of ¹⁸F-fluorodeoxyglucose (FDG) uptake in the bone marrow and spleen of patients with CRC and evaluate the relationship between FDG uptake estimates in these organs and serum inflammatory markers. In total, 411 patients who underwent preoperative FDG PET/computed tomography (CT) within 1 month of surgery were enrolled. The mean standardized uptake values of the bone marrow and spleen were normalized to the value of the liver, thereby generating bone marrow-to-liver uptake ratio (BLR) and spleen-to-liver uptake ratio (SLR) estimates. The value of BLR and SLR in predicting overall survival (OS) was assessed using the Cox proportional hazards model. The correlation between BLR or SLR and neutrophil-to-lymphocyte ratio (NLR) was evaluated. The predictive accuracy of BLR alone and in combination with SLR was compared using the integrated area under the receiver operating characteristic curves (iAUC). In the univariate analysis, BLR (> 1.06) and SLR (> 0.93) were significant predictors of OS. In the multivariate analysis, BLR was an independent predictor of OS (hazard ratio = 5.279; p < 0.001). Both BLR and SLR were correlated with NLR (p < 0.001). A combination of BLR and SLR was better than BLR alone at CRC prognostication (iAUC, 0.561 vs. 0.542). FDG uptake estimates in the bone marrow and spleen may be useful imaging-derived biomarkers of systemic inflammation, supporting CRC prognostication.

Association between bone marrow fluorodeoxyglucose uptake and recurrence after curative surgical resection in patients with T1-2N0M0 lung adenocarcinoma: a retrospective cohort study

Background

Evidence regarding the relationship between fluorodeoxyglucose (FDG) uptake in the bone marrow of patients with lung adenocarcinoma and prognosis is limited. This study aimed to identify whether bone marrow FDG uptake is a risk factor for recurrence in patients after curative surgical resection of T1-2N0M0 lung adenocarcinoma.

Methods

From January 2012 to December 2016, we retrospectively enrolled 195 pT1-2N0M0 lung adenocarcinoma patients who underwent both preoperative FDG positron emission tomography/computed tomography (PET/CT) and surgical resection from the lung adenocarcinoma database maintained by the PET/CT department at our hospital. After surgical resection, patients were followed up mainly through regular outpatient examinations. The maximum standardized uptake value (SUV_max) of the primary tumor, the mean FDG uptake of bone marrow (BM SUV), bone marrow-liver uptake ratio (BLR), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured from the pretreatment FDG PET/CT images. Multi-adjusted Cox proportional hazards models were built to evaluate the independent prognostic value of BLR in predicting recurrence-free survival (RFS). A restricted cubic spline regression model was conducted to provide more precise estimates and examine the shape of the associations between BLR and the risk of recurrence.

Results

The follow-up results showed that 30 of the 195 patients (15.4%) had tumor recurrence. Compared with non-recurrent patients, the primary tumor size in recurrent patients was larger, and the SUV_max, TLG, and serum C-reactive protein (CRP) levels were higher. Univariate analysis showed that BLR, tumor size, SUV_max, TLG, and CRP were significantly correlated with postoperative tumor recurrence. After adjustment for conventional confounding factors, the hazard ratio of BLR was 5.01 (95% CI, 1.32, 18.98) for the highest tertile of BLR compared with the lowest tertile. The multi-adjusted spline regression showed that BLR had a linear relationship with log relative risk (RR) for recurrence when BLR was lower than 0.7. Over this level, the effect stabilized, suggesting a saturation effect for BLR at a level of approximately 0.7 at recurrence.

Conclusions

BLR was an independent risk factor for predicting RFS in T1-2N0M0 lung adenocarcinoma patients after curative surgical resection. BLR can be used as a biomarker for evaluating the risk of lung cancer recurrence.

Clinical implications of increased uptake in bone marrow and spleen on FDG-PET in patients with bacteremia

PURPOSE

To investigate which clinical factors and laboratory values are associated with high FDG uptake in the bone marrow and spleen on 2-deoxy-2-[18F]fluoro-D-glucose (FDG) positron emission tomography (PET)/computed tomography (CT) in patients with bacteremia.

METHODS

One hundred forty-five consecutive retrospective patients with bacteremia who underwent FDG-PET/CT between 2010 and 2017 were included. Mean standard uptake values (SUV_mean) of FDG in bone marrow, liver, and spleen were measured. Bone marrow-to-liver SUV ratios (BLR) and spleen-to-liver SUV ratios (SLR) were calculated. Linear regression analyses were performed to examine the association of BLR and SLR with age, gender, hemoglobin, leukocyte count, platelets, glucose level, C-reactive protein (CRP), microorganism, days of antibiotic treatment before FDG-PET/CT, infection focus, use of immunosuppressive drugs, duration of hospital stay (after FDG-PET/CT), ICU admission, and mortality.

RESULTS

C-reactive protein (p = 0.006), a cardiovascular or musculoskeletal focus of infection (p = 0.000 for both), and bacteremia caused by Gram-negative bacteria (p = 0.002) were independently and positively associated with BLR, while age (p = 0.000) and glucose level before FDG-PET/CT (p = 0.004) were independently and negatively associated with BLR. For SLR, CRP (p = 0.001) and a cardiovascular focus of infection (p = 0.020) were independently and positively associated with SLR, while age (p = 0.002) and glucose level before FDG-PET/CT (p = 0.016) were independently and negatively associated with SLR.

CONCLUSION

High FDG uptake in the bone marrow is associated with a higher inflammatory response and younger age in patients with bacteremia. In patients with high FDG uptake in the bone marrow, a cardiovascular or musculoskeletal focus of infection is more likely than other foci, and the infection is more often caused by Gram-negative species. High splenic FDG uptake is associated with a higher inflammatory response as well, and a cardiovascular focus of infection is also more likely in case of high splenic FDG uptake.

[18F]FDG uptake of bone marrow on PET/CT for predicting distant recurrence in breast cancer patients after surgical resection

Background

The objective of this study was to investigate the prognostic value of 2-Deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) uptake of bone marrow (BM) and metabolic parameters of primary tumor on positron emission tomography/computed tomography (PET/CT) for predicting distant recurrence in patients with breast cancer.

Methods

Pretreatment [¹⁸F]FDG PET/CT images of 345 breast cancer patients were retrospectively evaluated. Maximum standardized uptake value, metabolic tumor volume, and total lesion glycolysis (TLG) of primary breast cancer and bone marrow-to-liver uptake ratio (BLR) on PET/CT were measured. A Cox proportional hazard regression model was used to evaluate the prognostic potential of parameters for predicting recurrence-free survival (RFS) and distant RFS. For Kaplan-Meier analysis, the specific cutoff values pf BLR and TLG were determined by the maximal chi-square method.

Results

The median follow-up duration of the enrolled patients was 48.7 months, and during follow-up, 36 patients (10.4%) experienced the cancer recurrence. BLR was significantly correlated with T stage, serum inflammatory markers, and recurrence pattern (p < 0.05). Patients with high BLR and TLG showed worse RFS and distant RFS than those with low BLR and TLG. On multivariate analysis, BLR was significantly associated with both RFS and distant RFS after adjusting for T stage, estrogen receptor status, and TLG (p = 0.001 for both). Only 0.5% of patients with TLG < 9.64 g and BLR < 0.91 experienced distant recurrence. However, patients with TLG ≥ 9.64 g and BLR ≥ 0.91 had a distant recurrence rate of 40.7%.

Conclusions

BLR on pretreatment [¹⁸F]FDG PET/CT were significant predictors for RFS and distant RFS in patients with breast cancer. By combining [¹⁸F]FDG uptake of BM and volumetric PET/CT index of breast cancer, the risk of distant recurrence could be stratified.

Risk stratification of symptomatic brain metastases by clinical and FDG PET parameters for selective use of prophylactic cranial irradiation in patients with extensive disease of small cell lung cancer

PURPOSE

To identify risk factors for developing symptomatic brain metastases and evaluate the impact of prophylactic cranial irradiation (PCI) on brain metastasis-free survival (BMFS) and overall survival (OS) in extensive disease small cell lung cancer (ED-SCLC).

MATERIALS AND METHODS

Among 190 patients diagnosed with ED-SCLC who underwent FDG PET/CT and brain Magnetic Resonance Imaging (MRI) prior to treatment, 53 (27.9%) received PCI while 137 (72.1%) did not. Prognostic index predicting a high risk of symptomatic brain metastases was calculated for the group without receiving PCI (observation group, n = 137) with Cox regression model.

RESULTS

Median follow-up time was 10.6 months. Multivariate Cox regression showed that the following three factors were associated with a high risk of symptomatic brain metastases: the presence of extrathoracic metastases (p = 0.004), hypermetabolism of bone marrow or spleen on FDG PET (p < 0.001), and high neutrophil-to-lymphocyte ratio (p = 0.018). PCI significantly improved BMFS in high-risk patients (1-year rate: 94.7% vs. 62.1%, p = 0.001), but not in low-risk patients (1-year rate: 100.0% vs. 87.7%, p = 0.943). However, PCI did not improve OS in patients at high risk for symptomatic brain metastases (1-year rate: 65.2% vs. 50.0%, p = 0.123).

CONCLUSION

Three prognostic factors (the presence of extrathoracic metastases, hypermetabolism of bone marrow or spleen on FDG PET, and high neutrophil-to-lymphocyte ratio) were associated with a high risk of symptomatic brain metastases in ED-SCLC. PCI was beneficial for patients at a high risk of symptomatic brain metastases in terms of BMFS, but not OS. Thus, selective use of PCI in ED-SCLC according to the risk stratification is recommended.

Effect of F-18 Fluorodeoxyglucose Uptake by Bone Marrow on the Prognosis of Head and Neck Squamous Cell Carcinoma

The purpose of this study was to assess the relationship between F-18 fluorodeoxyglucose (FDG) uptake in bone marrow (BM) on positron emission tomography/computed tomography (PET/CT) and survival in patients with head and neck squamous cell carcinoma (HNSCC). We retrospectively enrolled 157 HNSCC patients who underwent staging FDG PET/CT and subsequent treatment. On PET/CT, primary tumor metabolic characteristics, mean FDG uptake of BM (BM SUV), and BM-to-liver uptake ratio (BLR) were measured. The prognostic significance of FDG uptake of BM for predicting disease progression-free survival and distant failure-free survival was assessed using a Cox proportional hazards regression model. In univariate analysis for disease progression-free survival, increased BM SUV and BLR were associated with poor survival. In multivariate analysis, BLR (p = 0.044; hazard ratio, 1.96), TNM stage (p = 0.014; hazard ratio, 2.87) and maximum FDG uptake of the primary tumor (p = 0.046; hazard ratio, 2.38) were independently associated with disease progression-free survival. For distant failure-free survival, BLR, TNM stage, tumor size, and metabolic parameters of the primary tumor showed prognostic significance in univariate analysis. However, none of the variables showed significance in multivariate analysis. FDG uptake of BM in HNSCC patients might be a significant predictor for disease progression-free survival. Further studies with large patient population are needed to validate the results.

Diffuse splenic FDG uptake is predictive of clinical outcomes in patients with rectal cancer

This study aimed to investigate the correlations between diffuse splenic Fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) uptake on positron emission tomography/computed tomography (PET/CT) and inflammatory markers and to evaluate the prognostic significance of splenic FDG uptake in rectal cancer patients who underwent curative surgery. We retrospectively analyzed the data from 161 patients who underwent splenic FDG PET/CT staging and subsequent curative surgical resection of rectal cancer between July 2006 and September 2014. The spleen-to-liver uptake ratio (S/L ratio) was calculated by dividing the spleen SUV_mean by liver SUV_mean. We found significant positive correlations between the S/L ratio and neutrophil-to-lymphocyte ratio (P = 0.013) and platelet-to-lymphocyte ratio (P = 0.007). In a Kaplan–Meier analysis, patients with S/L ratio ≤0.815 had a significantly higher recurrence-free survival rate than those with S/L ratio >0.815 (P = 0.028). Also, patients with S/L ratio ≤0.731 had a significantly higher overall survival rate than those with S/L ratio >0.731 (P = 0.036). In multivariate analysis, higher S/L ratio, as well as male, poor differentiation, higher TNM stage, perineural invasion, and larger tumor size, was independently predictive of cancer recurrence (>0.815 vs ≤0.815, hazard ratio [HR]: 2.04, P = 0.046). With regard to OS, S/L ratio was also an independent prognostic factor for death during follow-up (>0.731 vs ≤0.731, HR: 3.81, P = 0.017). Our results show significant correlations between S/L ratio on PET/CT and systemic inflammatory markers. Further, S/L ratio was an independent prognostic factor for predicting recurrence and death in patient with rectal cancer after curative surgery.

Clinical utility of FDG uptake within reticuloendothelial system on F-18 FDG PET/CT for prediction of tumor recurrence in breast cancer

BACKGROUND

The aim of this study was to investigate the metabolism of the spleen, bone marrow (BM), and liver from preoperative F-18 FDG PET/CT scans for the prediction of recurrence in breast cancer.

METHODS

We retrospectively included 153 patients diagnosed with invasive ductal carcinoma (IDC) of the breast who underwent preoperative F-18 FDG PET/CT scan and a curative operation. The mean standardized uptake value (SUVmean) of the spleen, liver, and BM and maximum SUV (SUVmax) of primary tumors were measured. The relationships between spleen, BM, and liver metabolism and clinicopathologic parameters were evaluated, and possible prognostic parameters predicting recurrence were assessed using disease-free survival (DFS).

RESULTS

Spleen SUVmean was significantly correlated with primary tumor SUVmax, pathologic T (pT) stage, and histologic grade of primary tumor. BM SUVmean also showed a positive correlation with primary tumor SUVmax. Spleen SUVmean were significantly associated with recurrence from binary logistic regression analysis (P = 0.004). Spleen, BM, liver, and primary tumor SUVs were all significant prognostic factors for DFS in univariate Cox regression analysis (all P<0.024). Among all PET parameters analyzed, spleen SUVmean ≥ 2.21 (P = 0.032) was in the multivariable analysis the powerful poor prognostic factor predicting DFS that was independent of other clinicopathological features like T stage (pT >2; P = 0.009) and estrogen receptor (ER) status (ER negativity; P = 0.001).

CONCLUSION

Splenic metabolism together with pT stage and ER status was an independent prognostic factor for predicting recurrence in breast cancer. Metabolic activity of reticuloendothelial system such as spleen, liver or BM on preoperative F-18 FDG PET/CT can be a meritorious imaging factor for discriminating patients with IDC that require adjunctive therapy to prevent recurrence.

Prognostic value of 18F-fluorodeoxyglucose bone marrow uptake in patients with solid tumors: A meta-analysis

BACKGROUND

Several studies have reported the prognostic value of F-fluorodeoxyglucose (F-FDG) bone marrow uptake (BMU) measured by F-FDG positron emission tomography (F-FDG PET) in various cancers. We performed a meta-analysis to evaluate the prognostic value of F-FDG BMU in patients with solid tumors.

METHODS

Systematic searches of MEDLINE and Embase databases were performed using the keywords "F-FDG," "bone marrow," and "prognosis." All published human studies of the prognostic value of F-FDG BMU in patients with solid tumors were searched. The primary outcome was event-free survival (EFS), and the secondary endpoint was overall survival (OS); both of these were extracted directly from each study. The effects of F-FDG BMU on survival were assessed by using hazard ratios (HRs).

RESULTS

Ten studies with 1197 patients (8 studies reporting EFS in 1096 patients and 7 studies reporting OS in 836 patients) were included. In the EFS analysis, the combined HR was 1.75 (95% confidence interval [CI]: 1.45-2.11, P < .00001) in the random effects model (I = 51%, P = .05). The combined HR of OS was 1.40 (95% CI: 1.13-1.73, P = .002) in the random effects model (I = 52%, P = .05).

CONCLUSION

This meta-analysis has demonstrated that patients with a low level of F-FDG BMU have better EFS and OS than those with a high level of F-FDG BMU. Based on our results, we suggest that F-FDG BMU could be used as a biomarker for stratifying the risk of tumor progression in patients with solid tumors.

The Relationship Between Tumor Glucose Metabolism and Host Systemic Inflammatory Responses in Patients with Cancer: A Systematic Review

One of the most important and long recognized characteristics of tumor cells is their dysregulated cellular energetics with anaerobic driven glucose uptake. In patients with cancer, the prognostic value of the systemic inflammatory response has been well established, and the recent combination of PET and CT scanning combines the assessment of tumor physiologic activity with detailed anatomic localization. The aim of this study was to perform a systematic review of the assessment of the relationship between both the tumor and the host inflammatory responses using PET/CT. Methods: An extensive literature review using targeted subject headings was performed in the U.S. National Library of Medicine, the Excerpta Medica database, and the Cochrane Database of Systematic Reviews on March 31, 2018. On completion of the online search, the title and abstracts of each identified study were examined for relevance. Studies with duplicate datasets, not available in English, and that did not have full text availability were excluded. Full texts of relevant articles were obtained and were then examined to identify any further relevant articles. Results: Twelve studies containing 2,588 patients were included in the final analysis. All of the included studies used the ¹⁸F-FDG tracer in PET/CT imaging and had biochemical assessment of the systemic inflammatory response. Most studies showed a direct relationship between the tumor and bone marrow glucose uptake and host systemic inflammatory responses as measured by C-reactive protein (n = 2), albumin (n = 2), white cell count (n = 3), neutrophils (n = 2), and platelets (n = 2). Most of the studies (n = 8) also showed a direct relationship between tumor and bone marrow glucose uptake and poor outcomes. Conclusion: This review suggests a direct relationship between the tumor and bone marrow glucose uptake and host systemic inflammation. This may suggest new approaches for more optimal therapeutic targeting and monitoring strategies in patients with cancer.