Prognostic Value of Metabolic, Volumetric and Textural Parameters of Baseline [18F]FDG PET/CT in Early Triple-Negative Breast Cancer.

(1) Background: triple-negative breast cancer (TNBC) remains a clinical and therapeutic challenge primarily affecting young women with poor prognosis. TNBC is currently treated as a single entity but presents a very diverse profile in terms of prognosis and response to treatment. Positron emission tomography/computed tomography (PET/CT) with 18F-fluorodeoxyglucose ([18F]FDG) is gaining importance for the staging of breast cancers. TNBCs often show high [18F]FDG uptake and some studies have suggested a prognostic value for metabolic and volumetric parameters, but no study to our knowledge has examined textural features in TNBC. The objective of this study was to evaluate the association between metabolic, volumetric and textural parameters measured at the initial [18F]FDG PET/CT and disease-free survival (DFS) and overall survival (OS) in patients with nonmetastatic TBNC. (2) Methods: all consecutive nonmetastatic TNBC patients who underwent a [18F]FDG PET/CT examination upon diagnosis between 2012 and 2018 were retrospectively included. The metabolic and volumetric parameters (SUVmax, SUVmean, SUVpeak, MTV, and TLG) and the textural features (entropy, homogeneity, SRE, LRE, LGZE, and HGZE) of the primary tumor were collected. (3) Results: 111 patients were enrolled (median follow-up: 53.6 months). In the univariate analysis, high TLG, MTV and entropy values of the primary tumor were associated with lower DFS (p = 0.008, p = 0.006 and p = 0.025, respectively) and lower OS (p = 0.002, p = 0.001 and p = 0.046, respectively). The discriminating thresholds for two-year DFS were calculated as 7.5 for MTV, 55.8 for TLG and 2.6 for entropy. The discriminating thresholds for two-year OS were calculated as 9.3 for MTV, 57.4 for TLG and 2.67 for entropy. In the multivariate analysis, lymph node involvement in PET/CT was associated with lower DFS (p = 0.036), and the high MTV of the primary tumor was correlated with lower OS (p = 0.014). (4) Conclusions: textural features associated with metabolic and volumetric parameters of baseline [18F]FDG PET/CT have a prognostic value for identifying high-relapse-risk groups in early TNBC patients.

Prognostic Impact of Pretherapeutic FDG-PET in Localized Anal Cancer.

Due to the heterogeneity of tumour mass segmentation methods and lack of consensus, our study evaluated the prognostic value of pretherapeutic positron emission tomography with fluorodeoxyglucose (FDG-PET) metabolic parameters using different segmentation methods in patients with localized anal squamous cell carcinoma (SCC). Eighty-one patients with FDG-PET before radiochemotherapy were retrospectively analyzed. Semiquantitative data were measured with three fixed thresholds (35%, 41% and 50% of Maximum Standardized Uptake Value (SUVmax)) and four segmentation methods based on iterative approaches (Black, Adaptive, Nestle and Fitting). Metabolic volumes of primary anal tumour (P-MTV) and total tumour load (T-MTV: P-MTV+ lymph node MTV) were calculated. The primary endpoint was event-free survival (EFS). Seven multivariate models were created to compare FDG-PET tumour volumes prognostic impact. For all segmentation thresholds, PET metabolic volume parameters were independent prognostic factor and T-MTV variable was consistently better associated with EFS than P-MTV. Patient's sex was an independent variable and significantly correlated with EFS. With fixed threshold segmentation methods, 35% of SUVmax threshold seemed better correlated with EFS and the best cut-off for discrimination between a low and high risk of event occurrence was 40 cm3. Determination of T-MTV by FDG-PET using fixed threshold segmentation is useful for predicting EFS for primary anal SCC. If these data are confirmed in larger studies, FDG-PET could contribute to individualized patient therapies.

The impact of (18)F-FDG-PET/CT on Merkel cell carcinoma management: a retrospective study of 66 scans from a single institution.

PURPOSE: Merkel cell carcinomas (MCC) are neuroendocrine skin tumours frequently responsible for lymph node recurrence and metastatic disease and for which optimal management remains to be defined. The objective of this study was to evaluate the impact of (18)F-fluorodeoxyglucose ((18)F-FDG)-PET/computed tomography (CT) on the staging and treatment of MCC patients. MATERIALS AND METHODS: Twenty-three patients with a histologic diagnosis of MCC explored by (18)F-FDG-PET/CT between 2004 and 2012 were retrospectively included in the study. The detection of new lesions and the change in tumour staging and treatment were evaluated. For each patient, the (18)F-FDG-PET/CT results were compared with histological, clinical and imaging data. RESULTS: Sixty-six (18)F-FDG-PET/CT scans were performed at initial presentation (n=18), during subsequent monitoring (n=34) or during evaluation of chemotherapy response (n=14). The sensitivity, specificity and positive and negative predictive values of the (18)F-FDG-PET/CT were 97, 89, 94 and 94%, respectively. Two false-positive results (lymphadenitis) and one false-negative result (regional metastatic lymph nodes) were accounted for. Lesions not detected clinically or by conventional imaging techniques were found in 44% of the 52 (18)F-FDG-PET/CTs performed at initial presentation and subsequent monitoring, with, respectively, 50 and 41% of scans identifying new lesions. At initial presentation, (18)F-FDG-PET/CT led to a change in tumour staging in 39% of patients. Patient management was modified by (18)F-FDG-PET/CT results in one-third of patients (33% of patients at initial presentation, 32% during subsequent monitoring and 36% during evaluation of chemotherapy response). F-FDG-PET/CT incidentally detected four additional histologically confirmed cancers. CONCLUSION: This retrospective study confirms the important impact of (18)F-FDG-PET/CT on the management of MCC patients.

Unusual uptake of 18FDG by a hepatic adenoma.

Hepatic adenoma is a rare, benign tumor (with potential for malignant degeneration) and its diagnosis is difficult because its presentation is highly variable in medical imaging, particularly with MRI. In such cases, the use of a hepatic biopsy is usually recommended. (18)FDG-PET/CT provides a very significant predictive value for malignant hepatic lesions. In addition, the occurrence of an (18)FDG-avid benign tumor is a rare event. We hereby present the case of a patient with advanced breast cancer for whom an (18)FDG-PET/CT showed a focal hepatic uptake. A subsequent biopsy provided a diagnosis of a hepatic adenoma.

Laparoscopic sentinel lymph node (SLN) versus extensive pelvic dissection for clinically localized prostate carcinoma.

PURPOSE: Lymph node metastasis is an important prognostic factor in prostate cancer (PC). The aim of this prospective study was to evaluate the accuracy of sentinel lymph node (SLN) biopsy by laparoscopy in staging locoregional patients with clinically localized PC. METHODS: A transrectal ultrasound-guided injection of 0.3 ml/100 MBq (99m)Tc-sulphur rhenium colloid in each prostatic lobe was performed the day before surgery. Detection was performed intraoperatively with a laparoscopic probe (Gamma Sup CLERAD) followed by extensive resection. SLN counts were performed in vivo and confirmed ex vivo. Histological analysis was performed by haematoxylin-phloxine-saffron staining, followed by immunohistochemistry (IHC) if the SLN was free of metastasis. RESULTS: The study included 93 patients with PC at intermediate or high risk of lymph node metastases. The intraoperative detection rate was 93.5% (87/93). Nineteen patients had lymph node metastases, nine only in SLN. The false-negative rate was 10.5% (2/19). The internal iliac region was the primary metastatic site (43.3%). Metastatic sentinel nodes in the common iliac region beyond the ureteral junction were present in 13.3%. Limited or standard lymph node resection would have ignored 73.2 and 56.6% of lymph node metastases, respectively. CONCLUSION: Laparoscopy is suitable for broad identification of SLN metastasis, and targeted resection of these lymph nodes significantly limits the risk of extended surgical resection whilst maintaining the accuracy of the information.

Clinical and survival impact of FDG PET in patients with suspicion of recurrent cervical carcinoma.

PURPOSE: The aim of this retrospective study was to evaluate the contribution of (18)F-FDG PET to the clinical management and survival outcome of patients suspected of recurrent cervical carcinoma and in line with the hypothesis that early diagnosis of recurrent cervical cancer may improve overall survival. METHODS: A total of 40 patients underwent conventional imaging (CI) and FDG PET/CT for suspected cervical cancer. Clinical management decisions were recorded with CI and additional PET/CT. Discordances and concordances between CI and PET/CT results were compared to the final diagnosis as based on histopathology analysis or follow-up considered as the gold standard. RESULTS: The final diagnosis was established pathologically (n = 25) or by median clinical follow-up for 48 months after the PET (n = 15). The PET/CT was positive in 76% (20/26) of patients compared to 19% (6/26) with CI. Globally PET/CT modified the treatment plan in 55% (22/40) of patients and in 75% (18/24) when the CI was negative prior to PET/CT. These changes led to the use of previously unplanned therapeutic procedures in 37.5% (15/40). When FDG PET was positive for recurrence (> 3 foci), the median overall survival was 12 months (2-70) compared to patients with PET findings with < or = 1 focus for which the median survival was not attained (p = 0.007). A multivariate analysis of prognostic factors demonstrated that abnormal FDG uptake (> 3 foci) was the most significant factor (p < 0.03) for death from cervical cancer. CONCLUSION: FDG PET is a valuable tool in the case of suspected recurrence of cervical cancer on account of its impact on treatment planning and especially in predicting patient outcome.