Nuclear Medicine Communications

Synergic role of preoperative 18F-fluorodeoxyglucose PET and MRI parameters in predicting histopathological features of endometrial cancer

Background The aim of the present study is to explore the correlation between PET and MRI parameters of primary tumour and clinicopathological features and to determine their synergic predictive role in patients with endometrial cancer candidate to surgery. Methods Retrospective study including 27 patients with endometrial cancer and preoperative 18F-fluorodeoxyglucose (18F-FDG)-PET and MRI scan. The following parameters, calculated on the primary tumour, were used for analysis: maximum standardized uptake value (SUVmax), SUVmean, metabolic tumour volume (MTV) and total lesion glycolysis (TLG) for PET scans; mean apparent diffusion coefficient (ADCmean) and volume index for MRI scans. FIGO stage, grade, histotype, lymphovascular space invasion (LVSI) and myometrial invasion were the considered clinicopathological features. Results MRI volume index was a good predictor for deep myometrial invasion [area under the curve (AUC) = 0.85; P  = 0.003] and for LVSI (AUC = 0.74; P  = 0.039). A cutoff value of 9.555 for MRI volume index was predictive for deep myometrial invasion (sensitivity = 84.6%; specificity = 76.9%); a cutoff of 12.165 was predictive for LVSI (sensitivity = 69.2%; specificity = 83.3%). A TLG cutoff value of 26.03 was predictive for deep myometrial invasion (sensitivity = 84.6%; specificity = 76.9%). A high-direct correlation was found with MRI volume index (rho = 0.722; P  < 0.001); low-direct correlation with SUVmax (rho = 0.484; P  = 0.012), SUVmean (rho = 0.47; P  = 0.015) and TLG (rho = 0.482; P  = 0.013) were identified. The SUVmax/ADCmean ratio showed a low-direct correlation with percentage of myometrial invasion (rho = 0.467; P  = 0.016). Conclusion Volume index, TLG and SUVmax/ADCmean ratio are associated with deep myometrial invasion. As myometrial invasion is the index used to predict lymph node involvement in endometrial cancer, the synergic use of these imaging parameters may be suggested to predict lymphnodal metastases.

Complementary role of 18F-FDG PET/CT for sentinel lymph node algorithm in endometrial cancer with high-risk factors for lymphatic metastasis

Objective National Comprehensive Cancer Network (NCCN) sentinel lymph node (SLN) algorithm includes ‘mandatory steps’ for evaluating pelvic lymph nodes, but assessment of paraaortic area is left to surgeon’s discretion. In this study, we aimed to investigate the complementary role of preoperative 18F-FDG PET/computed tomography (CT) scan in detecting pelvic and especially paraaortic lymphatic metastasis in endometrial cancer patients with high-risk factor(s) according to Mayo Clinic Criteria and underwent SLN algorithm. Methods Patients who underwent preoperative 18F-FDG PET/CT scan, intraoperative SLN algorithm followed by systematic lymphadenectomy (LND) and had at least one high-risk criterion for lymphatic metastasis were included in this study. 18F-FDG PET/CT and SLN algorithm were compared with final histopathological results of systematic LND. Results Thirty-eight patients were eligible for the study. Lymphatic metastasis was seen in 10 patients (26.3%). Four cases had paraaortic lymphatic metastases which were together with pelvic (n:2) or isolated (n:2) metastases. SLN algorithm was able to detect all pelvic lymph node metastases. However, isolated paraaortic metastases were diagnosed only by 18F-FDG PET/CT. In 76 hemipelvises, sensitivity and negative predictive value of SLN algorithm for diagnosis of pelvic nodal metastasis were 100%, while sensitivity, specificity, positive predictive value and negative predictive value of 18F-FDG PET/CT were 45.4, 95.3, 62.5 and 91.1%, respectively. Conclusions Although SLN algorithm has an excellent diagnostic value for pelvic nodal metastasis, paraaortic metastasis might be underdiagnosed. 18F-FDG PET/CT may be a feasible tool to exclude paraaortic lymphatic metastasis in high-risk patients for lymphatic metastasis who will undergo SLN algorithm.

The relationship between posttreatment 18F-fluorodeoxyglucose PET/computed tomography restaging and metabolic parameters with the prognosis of uterine cervical cancer

Objective To evaluate the relationship between posttreatment 18 F-fluorodeoxyglucose ( 18 F-FDG) PET/computed tomography (CT) restaging with metabolic parameters and prognosis of uterine cervical cancer. Methods A total of 151 patients with cervical cancer who underwent 18 F-FDG PET/CT examination were retrospectively analyzed. The correlation between PET/CT restaging, maximum standard uptake value, whole body metabolic tumor volume (wbMTV), whole body total lesion glycolysis (wbTLG), related clinical factors, and prognosis was analyzed. Kaplan–Meier survival analysis was used to perform univariate analysis on clinical parameters and imaging parameters, and Cox’s proportional hazards regression model was used to perform multifactor analysis to explore the related factors affecting progression-free survival (PFS) and overall survival (OS) of patients with cervical cancer. Results With a median follow-up time of 24 months, the median OS of 151 cervical cancer patients was 43 months, and the 5-year survival rate was 50%; the median PFS was 33 months, and the 5-year PFS rate was 29%. Both univariate and multivariate analyses showed that PET/CT restaging and squamous cell carcinoma antigen (SCC-Ag) were significant prognostic factors for OS and PFS. Moreover, patients with downstaged PET/CT restaging showed significantly better 5-year OS and 5-year PFS rates than those no downstaging (87.0 vs. 24.6%; P  < 0.001 for OS; 50.7 vs. 18.5%; P  < 0.001 for PFS). Among patients with positive PET/CT findings, wbTLG and wbMTV were identified as independent prognostic factors for OS and PFS, respectively. Conclusion 18 F-FDG PET/CT restaging, serum SCC-Ag, wbMTV, and wbTLG are established as prognostic biomarkers in recurrent cervical cancer. Posttreatment PET/CT represents a sensitive and accurate imaging technique for predicting patient outcomes.

Prediction of preoperative lymph-vascular space invasion and survival outcomes of cervical squamous cell carcinoma by utilizing 18F-FDG PET/CT imaging at early stage

Objective To establish nomograms for predicting preoperative lymph-vascular space invasion (LVSI) and survival outcomes of cervical squamous cell carcinoma (CSCC) based on PET/CT radiomics. Methods One hundred and twenty-three patients with CSCC and LVSI status were enrolled retrospectively. Independent predictors of LVSI were identified through clinicopathological factors and PET/CT metabolic parameters. We extracted 1316 features from PET and CT volume of interest, respectively. Additionally, four models (PET-RS: radiomic signature of PET only; CT-RS: radiomic signature of CT only; PET/CT-RS + clinical data; PET/CT-RS: radiomic signature of PET and CT) were established to predict LVSI status. Calculation of radiomics scores of PET/CT was executed for assessment of the survival outcomes, followed by development of nomograms with radiomics (NR) or without radiomics (NWR). Results One hundred and twenty-three patients with pathologically confirmed CSCC had been categorized into two sets (training and testing sets). It was found that only maximum standardized uptake value (SUVmax) and squamous cell carcinoma antigen were independent predictors of LVSI. Meanwhile, the PET/CT-RS + clinical data outperformed the other three models in the training set [area under the curve (AUC): 0.91 vs. 0.861 vs. 0.81 vs. 0.814] and the testing set (AUC: 0.885 vs. 0.857 vs. 0.783 vs. 0.798). Additionally, SUVmax and LVSI had been demonstrated to be independent prognostic indicators for progression-free survival and overall survival. Decision curve analysis and calibration curve indicated that NRs were superior to NWRs. The survival outcomes were assessed. Conclusion PET/CT-based radiomic signature nomogram enables a new method for preoperative prediction of LVSI and survival prognosis for patients with CSCC.

Early prediction of distant metastasis in patients with uterine cervical cancer treated with definitive chemoradiotherapy by deep learning using pretreatment [18F]fluorodeoxyglucose positron emission tomography/computed tomography

Objectives A deep learning (DL) model using image data from pretreatment [18F]fluorodeoxyglucose ([18F] FDG)-PET or computed tomography (CT) augmented with a novel imaging augmentation approach was developed for the early prediction of distant metastases in patients with locally advanced uterine cervical cancer. Methods This study used baseline [18F]FDG-PET/CT images of newly diagnosed uterine cervical cancer patients. Data from 186 to 25 patients were analyzed for training and validation cohort, respectively. All patients received chemoradiotherapy (CRT) and follow-up. PET and CT images were augmented by using three-dimensional techniques. The proposed model employed DL to predict distant metastases. Receiver operating characteristic (ROC) curve analysis was performed to measure the model’s predictive performance. Results The area under the ROC curves of the training and validation cohorts were 0.818 and 0.830 for predicting distant metastasis, respectively. In the training cohort, the sensitivity, specificity, and accuracy were 80.0%, 78.0%, and 78.5%, whereas, the sensitivity, specificity, and accuracy for distant failure were 73.3%, 75.5%, and 75.2% in the validation cohort, respectively. Conclusion Through the use of baseline [18F]FDG-PET/CT images, the proposed DL model can predict the development of distant metastases for patients with locally advanced uterine cervical cancer treatment by CRT. External validation must be conducted to determine the model’s predictive performance.

Long-term assessment of clinical parameters and positron emission tomography parameters in predicting recurrence in uterine cervical cancer patients receiving definitive chemoradiotherapy

Objective The objective of this study was to assess the prognostic value of clinical factors and metabolic parameters measured using fluorodeoxyglucose PET (FDG-PET/CT) in predicting disease recurrence, as well as distant metastasis-free survival (DMFS), local recurrence-free survival (LRFS), and overall survival (OS) in patients with uterine cervical cancer who received definitive chemoradiotherapy. Methods The clinical data and FDG-PET parameters, including standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of 194 patients with biopsy-confirmed squamous cell carcinoma of cervical cancer were retrospectively analyzed. Univariate and multivariate analyses were used to ascertain prognostic factors associated with DMFS, LRFS, and OS. Results With a median follow-up of 12.5 years, 96 patients (49.5%) presented with disease recurrence, at a median of 9.9 months after chemoradiotherapy. Patients who experienced recurrence had significantly higher values for all FDG-PET parameters compared to patients who did not. In multivariate regression analysis, lymph node metastasis, MTV, and SUVmean were significantly correlated with distant metastasis, while local recurrence was only predicted by SUVmax. Lymph node metastasis, high MTV, SUVmean, and TLG predicted shorter DMFS, while only the primary tumor SUVmax predicted LRFS. Age, regional nodal metastasis, and higher MTV independently predicted shorter OS in multivariate analysis. Conclusion We found that metabolic parameters derived from FDG-PET/CT could serve as surrogates for disease recurrence in patients with cervical cancer who were treated with definitive chemoradiotherapy. Patients at high risk of distant metastasis could be defined using SUVmean and MTV, and for local recurrence, by using SUVmax.

Relationship between tumor heterogeneity and volume in cervical cancer: Evidence from integrated fluorodeoxyglucose 18 PET/MR texture analysis

Objective The aim of this study was to evaluate the effect of cervical cancer volume on PET/magnetic resonance (MR) texture heterogeneity. Materials and methods We retrospectively analyzed the PET/MR images of 138 patients with pathologically diagnosed cervical squamous cell carcinoma, including 50 patients undergoing surgery and 88 patients receiving concurrent chemoradiotherapy. Fluorodeoxyglucose 18 (18FDG)-PET/MR examination were performed for each patient before treatment, and the PET and MR texture analysis were undertaken. The texture features of the tumor based on gray-level co-occurrence matrices were extracted, and the correlation between tumor texture features and volume parameters was analyzed using Spearman’s rank correlation coefficient. Finally, the variation trend of tumor texture heterogeneity was analyzed as tumor volumes increased. Results PET texture features were highly correlated with metabolic tumor volume (MTV), including entropy-log2, entropy-log10, energy, homogeneity, dissimilarity, contrast, correlation, and the correlation coefficients (r s) were 0.955, 0.955, –0.897, 0.883, –0.881, –0.876, and 0.847 (P < 0.001), respectively. In the range of smaller MTV, the texture heterogeneity of energy, entropy-log2, and entropy-log10 increases with an increase in tumor volume, whereas the texture heterogeneity of homogeneity, dissimilarity, contrast, and correlation decreases with an increase in tumor volume. Only homogeneity, contrast, correlation, and dissimilarity had high correlation with tumor volume on MRI. The correlation coefficients (r s) were 0.76, –0.737, 0.644, and –0.739 (P < 0.001), respectively. The texture heterogeneity of MRI features that are highly correlated with tumor volume decreases with increasing tumor volume. Conclusion In the small tumor volume range, the heterogeneity variation trend of PET texture features is inconsistent as the tumor volume increases, but the variation trend of MRI texture heterogeneity is consistent, and MRI texture heterogeneity decreases as tumor volume increases. These results suggest that MRI is a better imaging modality when compared with PET in determining tumor texture heterogeneity in the small tumor volume range.

Associations of whole-body 18F-FDG PET/CT parameters and SCC-Ag level with overall survival in patients with cervical cancer

Objective To explore the whole-body metabolic tumour volume (WBMTV), whole-body total lesion glycolysis (WBTLG) and tumour whole-body maximum standardised uptake value (WBSUVmax) of post-treatment 18F-fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) in predicting the overall survival (OS) in patients with cervical squamous cell carcinoma (SCC). Methods The clinical data of 74 patients with cervical SCC who received 18F-FDG PET/CT were retrospectively analysed. WBMTV, WBTLG and WBSUVmax, as well as the serum SCC-Ag level, were measured. The Kaplan–Meier method and Cox regression were used to analyse the relationships of PET/CT parameters with OS. Results The risk of death was 13.942-fold greater in the PET-positive group than in the PET-negative group (P < 0.001). In the PET-positive group, univariate analysis showed that OS was significantly correlated with WBMTV and WBTLG; it was not correlated with WBSUVmax, SCC-Ag, age, pathological stage or treatment after PET (P > 0.05). Patients with positive PET findings were divided into two groups according to the median of WBMTV or WBTLG; there was a significant difference in OS between the two groups. The risk of death in patients with positive PET imaging findings and high SCC-Ag level was 18.356-fold greater than in patients with negative PET imaging findings (P < 0.001). Conclusions WBMTV and WBTLG have important prognostic value in the prediction of OS in post-treatment patients with cervical SCC. OS was significantly decreased in patients who had both positive PET imaging findings and high SCC-Ag level.

The role of 68Ga-FAPI PET/CT imaging in gynecological cancers: an integrative review

Clinical staging of gynecological cancers traditionally employs computed tomography (CT) scan or 18 fluorine-deoxyglucose PET/CT ( 18 F-FDG PET/CT), which have limited sensitivity, especially for early-stage ovarian cancer, borderline tumors, tumors with cystic/mucinous components, and those with low metabolic activity. Fibroblast activation protein inhibitor (FAPI) targets cancer-associated fibroblasts in tumor stroma independent of metabolic activity, providing favorable tumor-to-background contrast when used with PET imaging. We conducted an integrative review of FAPI PET/CT use in gynecological cancers for staging, treatment response assessment, and recurrence detection. Database searches yielded 205 documents, with 23 studies meeting inclusion criteria (12 original research articles, 7 case reports, 4 reviews). 68 Ga-FAPI PET/CT image was reported to be superior to 18 F-FDG PET/CT in differentiating high-grade from lower-grade ovarian cancer, detection of nodal, peritoneal, and pleural disease, as well as early relapses. 68 Ga-FAPI PET/CT showed enhanced detection of lymph node metastasis in newly diagnosed cervical cancer. However, its utility in endometrial cancer is limited by physiological uptake in normal uterine tissue. 68 Ga-FAPI PET/CT shows promising results for diagnosis and staging of ovarian and cervical cancers. Further research is warranted as this modality has potential to modify treatment approaches by improving detection capabilities beyond conventional imaging techniques, particularly for tumors with challenging characteristics that limit current diagnostic methods. Nucl Med Commun

Metabolic markers derived from 18F-FDG PET/CT in suspected recurrent ovarian carcinoma: predictive value for disease burden and prognosis

Objective This study aims to assess the role of 18F-fluorodeoxyglucose (FDG) PET/computed tomography (CT) in suspected recurrent ovarian carcinoma. Several clinical and PET parameters were assessed to evaluate disease burden and prognosis. Methods We did a single-center, retrospective study in patients with suspected recurrent ovarian carcinoma who underwent 18F-FDG PET/CT. The disease burden on the scan was evaluated. We calculated several semiquantitative markers, including standard uptake values (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG). Survival analysis was done with clinical parameters, CA-125 levels, disease distribution, and metabolic markers. Results Fifty-two patients were included in the study. Half of the patients had suspected recurrence within 12 months of primary diagnosis. PET/CT scan suggested disease in 35 (67.3%) patients. Multiple metastatic sites were noted in 21 (40.4%) patients. Extra-abdominal metastases were seen in 15 (28.8%) patients. Eight patients had 18F-FDG avid disease despite a low CA-125 level (<35 IU). Young patients (<50 years), extra-abdominal disease, multiple metastases, and higher restaging were associated with poor outcomes. Meanwhile, treatment history, CA-125 level, and post-PET/CT treatment had no significant effect on survival. MTV@40% SUV (>17.21) and TLG@40% SUV (>68.7) had the sensitivity of 87.5% and 75% for predicting disease outcome. Conclusion Recurrent ovarian carcinoma commonly presents with multiple metastasis and extra-abdominal metastases. 18F-FDG PET/CT-guided patterns of disease distribution were significant markers for poor prognosis. Disease burden on PET/CT-derived semiquantitative parameters was associated with poor outcomes.

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

Objective To clarify the relationship between 2-deoxy-2-[18F]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.

PET for predicting chemoradiotherapy survival in cervical cancer: the search continues

Objective Cervical c ancer is still a global health concern. The push for personalized care has been the mainstay and the use of noninvasive approaches to stratify patients is a corollary of this management strategy. 18 F-fluorodeoxyglucose PET/computed tomography is frequently used for cervical c ancer staging. Identifying predictive factors PET-based imaging scores could mean increased benefit for these patients, at no increased cost. Methods An observational study was conducted with stage IIB–IIIB cervical cancer patients receiving erlotinib concomitantly to standard therapy. Survival analyses employed Kaplan–Meier and Cox proportional hazards models, waterfall, and heatmap plots to investigate survival associations. Maximum and average PET measures were obtained before and 3 months after treatment. Results Thirty patients were enrolled in this phase I/II study. IIB Staging was significantly associated with longer survival when compared with IIIB. Simultaneous lower 2SD algorithm mean standard uptake value (SUV 2SD ) (<4.1) and greater BMI reduction (< −0.17 kg/m 2 ), or lower PERCIST SUV (SUV per ) (<7.6) and greater BMI reduction, predicted worse overall and progression-free survival ( P < 0.05). Unifying pretreatment maximum SUV (SUV max ), SUV per , and SUV 2SD demonstrated a trend toward significant overall survival stratification ( P = 0.057). In the heatmap analysis, there was a lack of high percentile pretreatment tumor-to-liver ratio, SUV max , SUV per , and SUV 2SD features in patients with worse endpoints. The waterfall plots suggested pretreatment lesion volume may predict volume reduction. Conclusion SUV 2SD and SUV per , paired with BMI variation, were associated with survival prediction. PET might play an important role in individualizing patients before treatment decisions for optimal management of locally advanced disease.

18F-FDG PET/computed tomography scan in patients with suspicion of recurrent neuroendocrine carcinoma of the cervix

Objectives The aim of this study was to investigate the value of [18F]fluoro-2-deoxy-D-glucose (18F-FDG) PET/computed tomography (CT) to detect recurrent cervical neuroendocrine carcinoma and its subsequent impact on patient management. Methods A total of 25 patients who had undergone 30 18F-FDG PET/CT studies for suspected recurrent cervical neuroendocrine carcinoma (18 small cells, 2 large cells, 1 atypical carcinoid, and 4 unclassified) were retrospectively analyzed. The findings of the PET/CT images were compared with the histopathologic results in 8 scans and with clinical follow-up in 22 scans. Results Of the 30 PET/CT studies, 63.3% (19/30) were positive for recurrence while 36.7% (11/30) were negative. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 18F-FDG PET/CT for detecting recurrent disease of cervical neuroendocrine carcinomas were 90.0, 90.0, 94.7, 81.8, and 90.0%, respectively. Metastasis to distant organs was the most common (89.4%), followed by lymph node recurrence (52.6%). Lungs were the most frequent site of distant metastasis (63.1%). 18F-FDG PET/CT findings led to the change of the management in 10 out of 25 patients (40%) by introducing the use of previously unplanned therapeutic procedures. Conclusions 18F-FDG PET/CT is an efficient technique for detecting recurrent cervical neuroendocrine carcinoma, and may thus contribute to improving patient management.

Radiosynthesis, optimization and pharmacokinetic study of the 99mTc-labeled human epidermal growth factor receptor 2 affibody molecule probe 99mTc-(HE)3ZHER2:V2

Objective To prepare a single-photon molecular probe easily labeled with 99mTc for evaluating the expression status of the human epidermal growth factor receptor 2 (HER2) receptor in ovarian cancer. Materials and methods The HEHEHE tag was added to the amino terminus of the affibody ZHER2:V2 by the method of gene recombinant expression, and a new affibody was synthesized which was easy to be labeled with 99mTc. The newly prepared affibody was labeled with 99mTc, and pharmacokinetic studies were carried out. Results A new affibody (HE)3ZHER2:V2 was prepared by the method of gene recombination and expression, which is easy to be labeled with 99mTc. The 99mTc labeling of the affibody can reach about 95% at 90°C. The pharmacokinetic study has shown that the 99mTc-labeled molecular probe has a fast clearance time in the blood and little side effect, which may be a promising single-photon emission computed tomography (SPECT) imaging agent. Conclusion The affibody (HE)3ZHER2:V2 is easy to be labeled with 99mTc, has a high yield and has a suitable half-life in vivo, which is suitable for the next step in ovarian cancer model imaging research.

Comparison of 68Ga-FAPI-04 and fluorine-18-fluorodeoxyglucose PET/computed tomography in the detection of ovarian malignancies

Background Currently, fluorine-18-fluorodeoxyglucose (18F-FDG) is the most frequently used diagnostical radiotracer for PET/computed tomography (PET/CT) in ovarian malignancies. However, 18F-FDG has some limitations. The fibroblast activation protein inhibitor (FAPI) previously demonstrated highly promising results in studies on various tumor entities and 68Ga-labeled FAPI presents a promising alternative to 18F-FDG. This study aimed to compare the performance of 68Ga-FAPI and 18F-FDG PET/CT for imaging of ovarian malignancies. Methods A total of 27 patients were included in this retrospective study conducted at the Affiliated Hospital of Southwest Medical University between June 2020 and February 2022. The 18F-FDG and 68Ga-FAPI uptakes of tumors, lymph nodes, and distant metastases were quantified using the maximum standardized uptake values, and the tumor-to-background ratios were also evaluated and calculated by using the Wilcoxon signed-rank test. Results Twenty-one patients with suspected (n = 11) and previously treated ovarian malignancies (n = 10) were in statistical analysis finally. For detecting tumors, 68Ga-FAPI PET/CT was more sensitive than 18F-FDG PET/CT [14 of 14 (100%) vs. 11 of 14 (78%)], lymph node metastases [75 of 75 (100%) vs. 60 of 75 (80%)] and superior to 18F-FDG PET/CT in terms of the peritoneal and pleural metastases [9 of 9 (100%) vs. 5 of 9 (56%)]. For four of the newly diagnosed patients (n = 11), 68Ga-FAPI PET/CT upstaged the clinical stage compared to 18F-FDG PET/CT. Conclusion 68Ga-FAPI PET/CT has superior potential in the detection of ovarian cancers, especially in peritoneal carcinomatosis. 68Ga-FAPI PET/CT may be a promising supplement for staging and follow-up of ovarian malignancies.

The value of the SUV ratio between lymph node and bone marrow in predicting pelvic lymphatic metastasis of patients with locally advanced cervical cancer: an integrated PET/CT study

Purpose This study aimed to evaluate the value of the standardized uptake value (SUV) ratio between lymph nodes and bone marrow (BM) measured by Fluorine-18-fluorodeoxyglucose PET and computed tomography (18F-FDG PET/CT) for predicting pelvic lymph node (PLN) metastasis in patients with locally advanced cervical cancer (LACC). Materials and methods A total of 62 patients with pathological stage Ib-IVa cervical cancer who underwent 18F-FDG PET/CT before treatment were reviewed retrospectively. We measured the metabolic and morphological parameters of lymph nodes and primary tumors, bone marrow SUV (SUVBM) and calculated the ratio of lymph nodes maximum SUV (SUVmax) to bone marrow SUV (SUVLN/BM) and the ratio of short-axis diameter to long-axis diameter (Ds/l) of lymph nodes. A receiver operating characteristic (ROC) curve was performed to evaluate the diagnostic efficacy of each parameter. Results There were 180 lymph nodes with pathological evidence included in the study. Our results indicated that Ds/l, SUVmax of lymph nodes (SUVLN) and SUVLN/BM were independent risk factors for PLN metastasis in LACC (P < 0.05), and SUVLN/BM showed the best diagnostic performance by ROC curve analysis. The SUVBM in the anemia group was significantly higher than that in the nonanemia group (3.05 vs. 2.40, P < 0.05); furthermore, false-positive cases decreased when the SUVLN/BM was used as the diagnostic criterion instead of SUVLN, especially in the anemia group. ROC curve analysis showed that the area under the curve value of the combination of SUVLN/BM and Ds/l was 0.884 (P < 0.05), which was higher than Ds/l or SUVLN/BM alone. Conclusions SUVLN/BM could improve the ability to predicting PLN metastasis in patients with LACC, and the diagnostic efficacy of the combination of SUVLN/BM and Ds/l might be better than that of a single parameter.

Predictive value of sentinel lymph node imaging and biopsy in early cervical cancers: correlation with scintigraphic uptake patterns and histology

Aim This study was designed to 1) assess the feasibility, standardization of sentinel lymph node imaging (SLNI) and biopsy in early cervical cancers and also to determine the detection rates. 2) To analyze the SLN uptake pattern and correlate the findings with the histological grades of tumor. Materials and methods 52 early cervical cancer patients underwent same-day 99m Tc sulfur colloid (filtered) SLNI and biopsy with gamma probing. Patients underwent radical hysterectomy, para-aortic and pelvic lymphadenectomy irrespective of sentinel lymph node biopsy (SLNB) findings. We analyzed the colloid transit times, uptake pattern, lymphatic groups involved and histology. Results A total of 203 hot nodes (100% detection rate) were detected and harvested. Study showed 100% sensitivity, specificity, and negative predictive value. Internal iliac nodes were predominantly involved. Lymphatic uptake patterns were graded and correlated with tumor histology (Ki index). Transit time was relatively prolonged in patients with aggressive tumors. Conclusion SLNI and biopsy in early cervical malignancies are feasible with high detection rate. Scintigraphic patterns of nodal uptake were relevant and found to correlate with the tumor histological grades. We found that nonfocal nodal uptake patterns were mainly encountered in patients with tumors having higher Ki index. Immunohistochemistry further facilitated identification of lymph nodal metastases. The visual grading system, implemented in this study provides a good indication of the degree of impairment of lymphatic drainage. Higher visual scintigraphic grade denotes greater lymphatic tumor burden.

The relationship between tumor mean standard uptake value (SUVmax) in preoperative PET/computed tomography and prognostic risk groups in endometrial cancer

Objective Our aim in this study was to determine the relationship between tumor mean standard uptake value (SUVmax) value in preoperative PET/computed tomography (CT) and prognostic risk groups in cases with endometrial cancer. Methods A total of 368 patients operated on for endometrial cancer were evaluated in the study. The SUVmax value of endometrial primary tumor of the patients screened within 30 days of operation, was compared with prognostic parameters and risk groups. P value <0.05 was considered significant for all tests. Results A statistically significant relationship was found between the mean SUVmax value and risk groups (P < 0.001), grade (P < 0.001), stage (P < 0.001), myometrial invasion of the tumor (P < 0.001), cervical involvement (P = 0.002), lymphovascular space invasion (LVSI) (P < 0.001), lymph node metastasis (P < 0.001), tumor size (P < 0.001), lymph node involvement in PET/CT (P < 0.001). There was no significant relationship found between the histologic type of tumor and the mean SUVmax value (P = 0.113). Cutoff SUVmax value for endometrial cancer tumor tissue, which will be used to determine the possible lymph node metastasis, was accepted as 19 as a result of the ROC analysis. The risk of lymph node metastasis was found 4.74 times (confidence interval, 2.510–8.977) higher in patients with SUVmax value above cutoff 19 (P < 0.001). Considering risk groups, it was observed that patients with mean SUVmax value above 19 were in intermediate-high and high risk group, 2.3 times more than those in low and intermediate risk group (P < 0.001). As a result of logistic regression analysis, in determining intermediate-high and high-risk groups, histological type (P < 0.001), myometrial invasion (P = 0.003), cervical invasion (CI) (P < 0.001), grade (P = 0.018) and SUVmax value (P = 0.028) had statistically significant importance. Conclusion The higher the mean SUVmax value in the endometrial cancer tumor tissue in preoperative PET/CT in patients with endometrial cancer, the higher the risk group of the patients.

Relationship between 18F-fluorodeoxyglucose PET/computed tomography metabolic parameters and clinicopathology in endometrial cancer

Objective Endometrial cancer (EC) is the most common invasive gynecological malignancy. This study aimed to retrospectively analyze the relationship between 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) parameters and clinicopathological factors in EC patients, and assess whether 18F-FDG PET/CT can be applied for predicting the expressed status of histologic molecular markers. Methods Pretreatment clinicopathological characteristics and 18F-FDG PET/CT parameters of maximum standard uptake value (SUVmax), metabolic tumor volume and total lesion glycolysis of primary lesion (MTV-P and TLG-P), and combination of primary lesion and metastases (MTV-C and TLG-C) were retrospectively reviewed in 101 patients with EC. Results The median age of these 101 patients was 55 years (range, 35–85 years), and 95 patients (94.1%) presented with abnormal vaginal bleeding, 26 patients (25.7%) with elevated serum cancer antigen 125 (CA-125) and 46 patients (45.5%) with increased human epididymis protein 4 (HE4). Sixty-nine cases were at International Federation of Gynecology and Obstetrics (FIGO) stage I, eight at stage II, 20 at stage III, and four at stage IV. FDG uptake was avid in all cases, and the median SUVmax, MTV-P, TLG-P, MTV-C, and TLG-C were 12.9 (range, 2.8–34.2), 8.1 (range, 0.9–547.8), 52.2 (range, 2.5–4420.6), 8.2 (range, 0.9–790.3), and 58.4 (range, 2.5–6972.2), respectively. Estrogen receptor (ER) and progesterone receptor (PR) positive expressions were in 93.1% (94/101) and 90.1% (91/101) patients, respectively. The median Ki-67 index of 101 cases was 40% (range, 0–95%). P53 pattern was tested in 89 patients and 24 cases were mutant type (27.0%). Mesenchymal-epithelial transition factor (c-Met) expression was investigated in 86 patients, and the positivity was in 36 patients (41.9%). Higher PET/CT metabolic parameters were observed in patients with elevated CA-125 and HE4, advanced FIGO stage and higher Ki-67 index (P < 0.05), but had no association with ER/PR expression, P53 pattern, and c-Met expression (P > 0.05). Conclusion FDG uptake in EC was associated with serum CA-125 and HE4, FIGO stage, and Ki-67 index, but no correlations were found between glucose metabolism and ER/PR, P53, and c-Met.