Positron Emission Tomography Staging Research Articles

ER-Targeted PET for Initial Staging and Suspected Recurrence in ER-Positive Breast Cancer

There are insufficient data comparing 16α-18F-fluoro-17β-estradiol (FES) positron emission tomography (PET) computed tomography (CT) with standard-of-care imaging (SOC) for staging locally advanced breast cancer (LABC) or evaluating suspected recurrence. To determine the detection rate of FES PET/CT and SOC for distant metastases in patients with estrogen receptor (ER)-positive LABC and recurrences in patients with ER-positive BC and suspected recurrence. This diagnostic study was conducted as a single-center phase 2 trial, from January 2021 to September 2023. The study design provided 80% power to find a 20% detection rate difference. Participants included patients with ER-positive LABC (cohort 1) or suspected recurrence (cohort 2). Data were analyzed from September 2023 to February 2024. Participants underwent both SOC imaging and experimental FES PET/CT. When there were suspicious lesions on imaging, 1 was biopsied for histopathological reference standard to confirm presence (true positive) or absence (false positive) of malignant neoplasm. The outcome of interest was the detection rate of FES PET CT vs SOC for distant metastases and recurrences. A total of 124 patients were accrued, with 62 in cohort 1 (median [IQR] age, 52 [32-84] years) and 62 in cohort 2 (median [IQR] age, 66 [30-93] years). In cohort 1, of 14 true-positive findings, SOC imaging detected 12 and FES detected 11 (P > .99). In cohort 2, of 23 true-positive findings, SOC detected 16 and FES detected 18 (P = .77). In 30 patients with lobular histology, of 11 true-positive findings, SOC detected 5 and FES detected 9 (P = .29). There were 6 false-positive findings on SOC and 1 false-positive finding on FES PET/CT (P = .13). In this diagnostic study with pathological findings as the reference standard, no difference was found between FES PET/CT and current SOC imaging for detecting distant metastases in patients with ER-positive LABC or recurrences in patients with ER-positive tumors and suspected recurrence. FES PET/CT could be considered for both clinical indications, which are not part of current Appropriate Use Criteria for FES PET. The findings regarding FES PET/CT in patients with lobular tumors, and for lower false positives than current SOC imaging, warrant further investigation.

PET Molecular Imaging in Breast Cancer: Current Applications and Future Perspectives.

Positron emission tomography (PET) plays a crucial role in breast cancer management. This review addresses the role of PET imaging in breast cancer care. We focus primarily on the utility of 18F-fluorodeoxyglucose (FDG) PET in staging, recurrence detection, and treatment response evaluation. Furthermore, we delve into the growing interest in precision therapy and the development of novel radiopharmaceuticals targeting tumor biology. This includes discussing the potential of PET/MRI and artificial intelligence in breast cancer imaging, offering insights into improved diagnostic accuracy and personalized treatment approaches.

Current Preoperative Management of Vulvar Squamous Cell Carcinoma: An Overview.

Vulvar carcinoma is a rare cancer affecting the genital tract, constituting 4% of gynecological tumors. Vulvar squamous cell carcinoma (VSCC) is the most common type. Diagnosis relies on biopsy during vulvoscopy, plus imaging such as ultrasonography (USG), magnetic resonance imaging (MRI) and positron emission tomography (PET). This review aims to lay out a thorough overview as to the current preoperative management of VSCC, both in case of vulvar and lymph node involvement. The data research was conducted using the following databases: MEDLINE, EMBASE, Web of Sciences, Scopus, ClinicalTrial.gov, OVID and Cochrane Library from 2010 to 2024. The selection criteria included only original articles. Seventeen studies were assessed for eligibility. A concordance rate of 62.3% for vHSIL and 65.2% for carcinoma at vulvoscopy, with a sensitivity of 98%, specificity of 40%, PPV (Positive Predictive Value) of 37% and NPV (Negative Predictive Value) of 98% in identifying malignant lesions was found. Regarding the reliability of PET for staging and assessing lymph node involvement, a mean SUV (Standardized Uptake Value) for malignant vulvar lesions of 8.4 (range 2.5-14.7) was reported. In the case of MRI, useful for the evaluation of loco-regional infiltration and lymph node involvement, the ratio of the short-to-long-axis diameter and the reader's diagnostic confidence for the presence of lymph node metastasis yielded accuracy of 84.8% and 86.9%, sensitivity of 86.7% and 87.5%, specificity of 81.3% and 86.2%, PPV of 89.7% and 87.5% and NPV of 76.5% and 86.2%, respectively. A long lymph node axis >10 mm and a short diameter >5.8 mm were found to be predictors of malignancy. At USG, instead, the two main characteristics of potentially malignant lymph nodes are cortical thickness and short axis length; the combination of these ultrasound parameters yielded the highest accuracy in distinguishing between negative and positive lymph nodes. Despite the heterogeneity of the included studies and the lack of randomized clinical trials, this review provides a broad overview of the three imaging tools used for the presurgical management of VSCC. Nowadays, although MRI and PET represent the gold standard, ultrasound evaluation is taking on a growing role, as long as it is carried out by expert sonographer. The management of this rare disease should be always performed by a multidisciplinary team in order to precisely stage the tumor and determine the most suitable treatment approach.

Analysis of risk factors associated with distant metastasis detected at laparotomy in patients with radiologically resectable pancreatic ductal adenocarcinoma

AbstractPurposeThis study aimed to evaluate the preoperative risk factors in patients with radiologically resectable pancreatic ductal adenocarcinomas (PDACs), deemed to be unresectable intraoperatively.MethodsData on patients radiologically diagnosed with resectable PDACs and subsequently underwent pancreatectomy between January 2020 and December 2021 were retrospectively collected. Preoperative risk factors were also analysed.ResultsFifty‐three patients with resectable PDAC who underwent laparotomy for curative intent were divided into the no‐metastases (n = 32) and distant metastases (n = 21) groups. Univariate analysis identified factors associated with distant metastases found intraoperatively, such as significant weight loss (odds ratio [OR] 5.29, P = .02), tumour size >35 mm (OR 4.15, P = .017), tumours located at the body and tail of the pancreas (OR 6, P = .041), superior mesenteric vein (SMV) abutment from the tumour (OR 7.5, P = .02), serum carbohydrate antigen 19‐9 > 385 IU/mL (OR 3.58, P = .031) and serum carcinoembryonic antigen (CEA) levels >9 IU/mL. However, multivariate analysis showed that only significant weight loss (adjusted OR 27.19, P = .011), SMV abutment from the tumour (adjusted OR 52.64, P = .01) and serum CEA levels >9 IU/mL were associated with distant metastases found intraoperatively.ConclusionSignificant weight loss, SMV abutment and serum CEA levels of >9 IU/mL were intraoperatively associated with distant metastases. Staging laparoscopy and positron emission tomography–computed tomography may reduce unnecessary laparotomies and change clinical management in these patients.

Investigating PET Responses to Treatment in Nodular Lymphocyte-Predominant Hodgkin Lymphoma.

There is no standard treatment for nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL). Although response by positron emission tomography (PET) for classic Hodgkin lymphoma (cHL) has allowed for response-adapted treatment, similar approaches for NLPHL have not been developed. This is in part due to the lack of data for PET response to treatment. Therefore, we sought to investigate PET responses to management for NLPHL. We retrospectively identified 47 patients who were diagnosed with or treated for NLPHL between 2001-2018 at a single institution and underwent a staging PET. We recorded clinical data and PET metrics for patients who received various forms of management, including chemotherapy (CT), radiation therapy (RT), combined modality therapy (CMT = CT+RT, with rituximab in a subset), rituximab monotherapy, and observation after excision. Metabolic response was scored according to the Deauville 5-point scale criteria, with complete metabolic response defined as a score 1-3. We identified 47 patients with median age of 26 (IQR = 17-50). They predominantly were male (74.5%) and had early stage (23.4% I, 36.2% II) versus advanced stage (29.8% III, 10.5% IV) NLPHL. The majority of patients had their immunoarchitectural pattern scored (n = 36, 76.6%), with typical pattern (A/B) being the most frequent type (58.3%). The median follow-up was 5.7 years (IQR = 2.3-9.3). Overall survival was 100% at 5 years and 92.3% at 10 years. Primary management included CMT (n = 10, 21.3%; with rituximab in a subset n = 1, 10.0%), CT alone (n = 22, 46.8%; with rituximab in a subset n = 5, 22.7%), RT alone (n = 8, 17.0%), rituximab alone (n = 3, 6.4%), and observation after excision (n = 4, 8.5%). On baseline PET, median SUVmax was 10.7 (range = 1.7-35.4). Of the 10 patients who received CMT, the complete metabolic response rates were 42.9% at interim-chemotherapy PET and 75% at post-chemotherapy PET, which improved to 100% after consolidative radiotherapy. There was no difference in complete metabolic response rate to chemotherapy for typical versus variant pattern (P = 0.60). Of the 22 patients who received CT alone, 66.7% had a complete metabolic response at the interim PET and 72.7% at the end of chemotherapy. For RT, rituximab alone, and observation, the complete metabolic response rates at median 3 months (range 1-5 months) after treatment were 87.5%, 66.7%, 75.0%, respectively. Based on our cohort, we found that patients with NLPHL had a lower complete metabolic response to CT (∼75%) compared to cHL (∼85-90%) and PET-response was improved following RT for those receiving CMT. There was no significant difference in PET-response for those with variant versus typical immunoarchitectural patterns. Our findings will allow for the development of PET response-adapted therapy for NLPHL.

An Outstanding Rapid Clinical Response to Olaparib in A Patient with gBRCA2m Fungating Breast Cancer: A Case Report

Background: Breast cancer is a heterogeneous, phenotypically complex disease made up of various biologic subgroups with unique behaviors and therapeutic responses. Noted that despite lack of a cure for metastatic breast cancer (MBC), there have been appreciable advancements in survival that have occurred at the same time as newer systemic treatments. BRCA1 or BRCA2 mutations cause homologous recombination deficient (HRD) cells, which are vulnerable to PARPi agent treatment. Case Report: This case report presents a 40 years old single female, known case of multiple co-morbidities who was diagnosed with Bilateral breast cancer in June 2022. She has a Positive family history of malignancy; mother died from endometrial cancer and aunt from paternal side has breast cancer. She underwent needle core biopsy from her Right breast mass, which revealed Invasive high-grade ductal carcinoma with metaplastic features (foci of keratinizing squamous differentiation, and myxoid stromal change). DCIS, of intermediate and high grades and a solid pattern, was noted, focally suspicious for lymphovascular invasion, Triple negative (ER negative (<1%), PR negative (<1%) and her-2 (+2) FISH negative (Her-2 Low), KI 67= 70%. Left breast mass Biopsy done on 12/9/2022 showed Invasive Lobular carcinoma, grade 3, ER negative, PR negative, Her-2 +1, KI 67=70%, BRCA2 POSITIVE & PDL1 CPS score 10%. Staging positron emission tomography scan done on 10 October 2022. She had a Large hypermetabolic fungating right breast mass infiltrating the chest wall, consistent with biopsy-proven malignancy. Additional smaller FDG-avid lesions noted in the right breast. Moreover, she had FDG-avid right axillary and right internal mammary nodal metastases. Mildly FDG-avid left breast mass, consistent with biopsy-proven malignancy. FDG-avid liver and pleural metastases. She was started on PARP inhibitor (Olaparib) on 20/9/2022 after which she had amazing fast clinical response leading to falling off the large fungating mass. Conclusion: The chance of developing breast and ovarian cancer is extremely elevated if one possesses BRAC 1 or BRCA 2 mutation. In this situation, PARP inhibitors, mutation-targeted therapy, has better outcomes in reducing the morbidity and mortality associated with metastatic breast cancer (Olaparib).

Imaging in Gastric Cancer: Current Practice and Future Perspectives

Gastric cancer represents one of the most common oncological causes of death worldwide. In order to treat patients in the best possible way, the staging of gastric cancer should be accurate. In this regard, endoscopy ultrasound (EUS) has been considered the reference standard for tumor (T) and nodal (N) statuses in recent decades. However, thanks to technological improvements, computed tomography (CT) has gained an important role, not only in the assessment of distant metastases (M status) but also in T and N staging. In addition, magnetic resonance imaging (MRI) can contribute to the detection and staging of primary gastric tumors thanks to its excellent soft tissue contrast and multiple imaging sequences without radiation-related risks. In addition, MRI can help with the detection of liver metastases, especially small lesions. Finally, positron emission tomography (PET) is still considered a useful diagnostic tool for the staging of gastric cancer patients, with a focus on nodal metastases and peritoneal carcinomatosis. In addition, it may play a role in the treatment of gastric cancer in the coming years thanks to the introduction of new labeling peptides. This review aims to summarize the most common advantages and pitfalls of EUS, CT, MRI and PET in the TNM staging of gastric cancer patients.

Moderne definitive Radiochemotherapie – State of the Art-Umsetzung und neue Konsolidierungsstrategien

BackgroundIn locally advanced non-small-cell lung cancer (NSCLC), the addition of chemotherapy to radiotherapy and consolidation with durvalumab leads to a significant increase in overall survival and represents the most profound innovation of the last decade.ObjectivesAnalysis of new possibilities for the state-of-the-art implementation of definitive radiochemotherapy concepts.Materials and methodsEvaluation of prospective and randomised studies regarding improvements in treatment outcomes.ResultsOverall survival benefit of consolidating checkpoint inhibitor therapy after combined radiochemotherapy with durvalumab is 43% (95% confidence interval 38–47%) versus 33% (27–40%) in the placebo group in an updated analysis of the PACIFIC trial for 5‑year survival; stratified hazard ratio for death is 0.72 (95% CI 0.59–0.89, p = 0.0025). In the dose escalation studies, increased pulmonary and oesophageal side effects were observed, so no immediate clinical benefit could be derived from the increase in local efficacy. Improved imaging before and during therapy and optimised possibilities of dose application, especially by using intensity-modulated radiotherapy (IMRT), allow selective sparing of healthy structures, which increases the ability to safely intensify radiotherapy also in connection with new immunomodulatory substance combinations.ConclusionThe integration of immunotherapy, the stringent use of fluorodeoxyglucose positron emission tomography (FDG-PET) in staging and radiation planning, the widespread use of highly conformal radiation techniques (IMRT; volumetric modulated arc therapy, VMAT) and the consistent application of image-guided radiotherapy have led to significant improvements in treatment outcomes.

Retrospective audit: Utility of PET scan in routine preoperative rectal cancer staging.

Accurate staging for rectal cancer is pertinent with recent introduction of rectum-sparing approaches for patients showing complete clinical response on restaging. Positron emission tomography(PET) is used in detection of recurrence or metastasis, but its value in routine preoperative rectal cancer staging remains unclear. Studies report that preoperative PET altered the stage in 39% and changed the management in 17-27% of patients. Our study aims to look at the utility of PET in routine preoperative staging of rectal cancer within 2 two colorectal units, and to determine if PET did result in a change in management. Patients in Nepean Hospital (NSW) and Peter MacCallum Cancer Centre (VIC) who were diagnosed with rectal cancer between 1 January 2017 and 31 December 2021 were included in this retrospective study. All patients who did not have a PET scan were excluded. PET scan results were then compared with MRI and CT results. Three hundred and fifty-seven patients were included in the study. 30.3% of the patients had Stage 3 rectal cancer. 71.7% received neoadjuvant therapy. PET scan provided additional information in 55.5% of patients when compared with CT and MRI alone; 18.2% of the PET findings resulted in an altered management for the patient. PET scan can be a valuable tool in accurate staging, especially for ambiguous or equivocal lesions on CT. Our study demonstrated that additional information from PET scan resulted in an altered management plan in 18.2% of the patients. PET/MRI as a newer modality may be more accurate with reduced radiation exposure.

Neuronal Alterations in Secondary Thalamic Degeneration Due to Cerebral Infarction: A 11C-Flumazenil Positron Emission Tomography Study.

Background:Studies using animal experiments have shown secondary neuronal degeneration in the thalamus after cerebral infarction. Neuroimaging studies in humans have revealed changes in imaging parameters in the thalamus, remote to the infarction. However, few studies have directly demonstrated neuronal changes in the thalamus in vivo. The purpose of this study was to determine whether secondary thalamic neuronal damage may manifest as a decrease in central benzodiazepine receptors in patients with cerebral infarction and internal carotid artery or middle cerebral artery disease.Methods:We retrospectively analyzed the data of 140 patients with unilateral cerebral infarction ipsilateral to internal carotid artery or middle cerebral artery disease. All patients had quantitative measurements of 11C-flumazenil binding potential (FMZ-BP), cerebral blood flow, and cerebral metabolic rate of oxygen using positron emission tomography in the chronic stage. Region of interest analysis was performed using NeuroFlexer—an automated region of interest analysis software using NEUROSTAT.Results:In the thalamus ipsilateral to the infarcts, the values of FMZ-BP, cerebral blood flow, and cerebral metabolic rate of oxygen were significantly lower than those in the contralateral thalamus. Significant correlations were found between the ipsilateral-to-contralateral ratio of FMZ-BP and the ipsilateral-to-contralateral ratio of cerebral blood flow or cerebral metabolic rate of oxygen in the thalamus. Patients with corona radiata infarcts and striatocapsular infarcts had significantly decreased ipsilateral-to-contralateral FMZ-BP ratio in the thalamus compared with those without. The ipsilateral-to-contralateral ratio of FMZ-BP in the thalamus was significantly correlated with the ipsilateral-to-contralateral cerebral metabolic rate of oxygen ratio in the frontal cortex and showed a significant negative correlation with the number of perseverative errors on the Wisconsin Card Sorting Test.Conclusions:Secondary thalamic neuronal damage may manifest as a decrease in central benzodiazepine receptors in patients with cerebral infarction and internal carotid artery or middle cerebral artery disease, which may be associated with frontal lobe dysfunction.

Achieving Consensus for Management of Hormone-Sensitive, Low-Volume Metastatic Prostate Cancer in Italy.

Metastatic hormone-sensitive prostate cancer (mHSPC) is usually categorized as high- or low-volume disease. This is relevant because low- and high-volume metastatic disease are associated with different outcomes, and thus management of the two forms should differ. Although some definitions have been reported, the concept of oligometastatic disease is not so clearly defined, giving rise to further variability in the choice of treatment, mainly between systemic agents and radiotherapy, especially in the era of metastasis-directed therapy. With the aim of providing clinicians with guidance on best practice, a group of medical and radiation oncologists, experts in prostate cancer, used the round robin method to generate a series of consensus statements on management of low-volume mHSPC. Consensus was obtained on three major areas of controversy: (1) with regard to clinical definitions of mHSPC, it was held that oligometastatic and low-volume disease refer to different concepts and should not be used interchangeably; (2) regarding therapy of de novo low-volume metastatic disease, androgen deprivation therapy alone can be considered undertreatment, and all patients should be evaluated for systemic treatment combinations; local therapy should not be denied in patients with mHSPC, regardless of the intensity of systemic therapy, and metastasis-directed therapy can be proposed in selected cases; (3) with regard to treatment of metachronous metastatic disease, patients should be evaluated for systemic treatment combinations. Metastasis-directed therapy can be proposed to delay systemic treatment in selected cases, especially if prostate-specific membrane antigen positron emission tomography staging has been performed and when indolent disease occurs. It is hoped that clinicians treating patients with mHSPC in daily practice will find this expert opinion of value.

Results in mediastinal lymph node staging of surgical lung cancer: Data from the prospective cohort of the Spanish Video-Assisted Thoracic Surgery Group

ObjectivesThe objective of this study was to assess the diagnostic performance of combined computerised tomography (CT) and positron emission tomography (PET) in mediastinal staging of surgical lung cancer based on data obtained from the prospective cohort of the Spanish Group for Video-Assisted Thoracic Surgery (GEVATS). MethodsA total of 2782 patients underwent surgery for primary lung carcinoma. We analysed diagnostic success in mediastinal lymph node staging (cN2) using CT and PET. Bivariate and multivariate analyses were performed of the factors involved in this success. The risk of unexpected pN2 disease was analysed for cases in which an invasive testing is recommended: cN1, the tumour centrally located or the tumour diameter >3 cm. ResultsThe overall success of CT together with PET was 82.9% with a positive predictive value of 0.21 and negative predictive value of 0.93. If the tumour was larger than 3 cm and for each unit increase in mediastinal SUVmax, the probability of success was lower with OR 0.59 (0.44–0.79) and 0.71 (0.66–0.75), respectively. In the video-assisted thoracic surgery (VATS) approach, the probability of success was higher with OR 2.04 (1.52–2.73). The risk of unexpected pN2 increased with the risk factors cN1, the tumour centrally located or the tumour diameter >3 cm: from 4.5% (0 factors) to 18.8% (3 factors) but did not differ significantly as a function of whether invasive testing was performed. ConclusionsCT and PET together have a high negative predictive value. The overall success of the staging is lower in the case of tumours >3 cm and high mediastinal SUVmax, and it is higher when VATS is performed. The risk of unexpected pN2 is higher if the disease is cN1, the tumour centrally located or the tumour diameter >3 cm but does not vary significantly as a function of whether patients have undergone invasive testing.

Resultados de la estadificación clínica ganglionar mediastínica del cáncer pulmonar quirúrgico: datos de la cohorte prospectiva nacional del Grupo Español de Cirugía Torácica Videoasistida

ObjectivesThe objective of this study was to assess the diagnostic performance of combined computerised tomography (CT) and positron emission tomography (PET) in mediastinal staging of surgical lung cancer based on data obtained from the prospective cohort of the Spanish Group for Video-Assisted Thoracic Surgery (GEVATS). MethodsA total of 2782 patients underwent surgery for primary lung carcinoma. We analysed diagnostic success in mediastinal lymph node staging (cN2) using CT and PET. Bivariate and multivariate analyses were performed of the factors involved in this success. The risk of unexpected pN2 disease was analysed for cases in which an invasive testing is recommended: cN1, the tumour centrally located or the tumour diameter >3cm. ResultsThe overall success of CT together with PET was 82.9% with a positive predictive value of 0.21 and negative predictive value of 0.93. If the tumour was larger than 3cm and for each unit increase in mediastinal SUVmax, the probability of success was lower with OR 0.59 (0.44–0.79) and 0.71 (0.66–0.75), respectively. In the video-assisted thoracic surgery (VATS) approach, the probability of success was higher with OR 2.04 (1.52–2.73). The risk of unexpected pN2 increased with the risk factors cN1, the tumour centrally located or the tumour diameter >3cm: from 4.5% (0 factors) to 18.8% (3 factors) but did not differ significantly as a function of whether invasive testing was performed. ConclusionsCT and PET together have a high negative predictive value. The overall success of the staging is lower in the case of tumours >3cm and high mediastinal SUVmax, and it is higher when VATS is performed. The risk of unexpected pN2 is higher if the disease is cN1, the tumour centrally located or the tumour diameter >3cm but does not vary significantly as a function of whether patients have undergone invasive testing.

MP51-18 TRENDS OF PRIMARY STAGING FOR NEWLY DIAGNOSED PROSTATE CANCER – ASSESSING THE UPTAKE OF PROSTATE SPECIFIC MEMBRANE ANTIGEN POSITRON EMISSION TOMOGRAPHY: A POPULATION BASED ANALYSIS

You have accessJournal of UrologyCME1 May 2022MP51-18 TRENDS OF PRIMARY STAGING FOR NEWLY DIAGNOSED PROSTATE CANCER – ASSESSING THE UPTAKE OF PROSTATE SPECIFIC MEMBRANE ANTIGEN POSITRON EMISSION TOMOGRAPHY: A POPULATION BASED ANALYSIS Marlon Perera, Nathan Papa, Declan Murphy, Nathan Lawrentschuk, Melanie Evans, Jeremy Millar, and Damien Bolton Marlon PereraMarlon Perera More articles by this author , Nathan PapaNathan Papa More articles by this author , Declan MurphyDeclan Murphy More articles by this author , Nathan LawrentschukNathan Lawrentschuk More articles by this author , Melanie EvansMelanie Evans More articles by this author , Jeremy MillarJeremy Millar More articles by this author , and Damien BoltonDamien Bolton More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002626.18AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Prostate specific membrane antigen (PSMA) positron emission tomography (PET) in advanced prostate cancer imaging demonstrates improved sensitivity and specificity compared to conventional imaging. We aimed to assess prostate cancer staging practice patterns in Victoria, Australia using population-based data. METHODS: We extracted data on men with a tissue diagnosis of prostate cancer between January 2017 and December 2019 from the Victorian Prostate Cancer Outcomes Registry (PCOR-Vic). We evaluated trends and comparisons between patients receiving PET/CT (with or without conventional imaging (CImg)), and CImg alone, and analysed imaging modality as predictor of clinical regional node positive disease (cN1 vs cN0/X), metastatic disease (cM1 vs cM0/X), and treatment received. RESULTS: In total, 10288 patients in the registry had either a staging PET scan (n = 1599, 16%), CImg without PET scan (n = 3539, 34%), or no recorded PET or CImg (n = 5150, 50%). The proportion of all imaged patients who received staging PET increased from 21% to 39% from the first to last six-month period, and in the patients with grade group ≥3, the increase was 23-43%. After adjustment for grade group, PET vs CImg-only patients were observed to have a higher proportion of cN1 disease (OR = 2.48, 95% CI: 2.04-3.03) but not cM1 disease (OR = 1.06, 95% CI: 0.87-1.29). CONCLUSIONS: Our registry data highlights the rapid uptake of PET imaging, particularly in higher grade disease. Based on this data, we underline the increased diagnosis of nodal disease, thus potentially optimizing patient selection prior to definitive treatment for prostate cancer. Source of Funding: Marlon Perera is sponsored by the Australian-America Fulbright Commission administered through a 2021-2022 Fulbright Future Scholarship funded by The Kinghorn Foundation © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e883 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Marlon Perera More articles by this author Nathan Papa More articles by this author Declan Murphy More articles by this author Nathan Lawrentschuk More articles by this author Melanie Evans More articles by this author Jeremy Millar More articles by this author Damien Bolton More articles by this author Expand All Advertisement PDF DownloadLoading ...

Correlating Quantitative Para-Aortic Lymph Node Computed Tomography Parameters With Fluorodeoxyglucose Positron Emission Tomography for Cervical Cancer Staging: Possible Solution for Resource Constrained Countries.

The aim of the study was to determine the most accurate quantitative morphological parameters on computed tomography (CT) that correlate with fluorodeoxyglucose (FDG)-avid para-aortic nodes (PANs) in patients with cervical cancer. A single-institution retrospective evaluation was performed of women with cervical cancer who underwent pretreatment positron emission tomography (PET)/CT and radiotherapy therapy planning CT between 2009 and 2020. A node-by-node correlation between pretreatment CT and PET/CT was performed for the reference standard of FDG avidity for short- and long-axis diameters, volume, and long-/short-axis ratio (L/S). The FDG-avid PANs were defined as PET-positive and non-FDG-avid PANs from patients without PET-determined PAN metastasis were defined as PET negative. Area under the receiver operator curve was calculated to access diagnostic accuracy of the different quantitative parameters. A total of 94 women (mean age ± standard deviation, 52 ± 13 years) with cervical cancer were included. Forty-seven patients had PET-positive PANs (181 PET-positive PANs) and 47 patients had no PET-positive PANs (141 PET-negative PANs). The area under the receiver operator curve for volume (0.945) was greater ( P < 0.001) than that of short axis (0.895), long axis (0.885), and L/S (0.583). At a specificity set point of 0.90 (127/141 PANs), the cutoff for volume was 0.443 cm 3 or greater (0.85 sensitivity [154/181 PANs]; 95% confidence interval, 0.83-0.93) and for short-axis diameter was 5.9 mm or greater (0.75 sensitivity [135/181 PANs]; 95% confidence interval, 0.68-0.81). Para-aortic lymph node volume demonstrated that improved node-by-node correlation between CT and PET/CT compared with short-axis diameter, long-axis diameter, and L/S and is an alternative to improve detection of PAN suspicious of metastatic diseases in locations without access to PET/CT.

Diagnostic performance of positron emission tomography in the staging of pseudomyxoma peritonei

BackgroundPseudomyxoma peritonei (PMP) is a rare clinical entity, commonly derived from a mucin-producing tumour of the appendix. International consensus is unclear on the role of positron emission tomography (PET) in preoperative staging. This study aimed to assess the ability of preoperative PET in predicting the histological grade of PMP. MethodsAll patients scheduled for cytoreductive surgery (CRS) +/− hyperthermic intraperitoneal chemotherapy (HIPEC) for PMP who underwent preoperative PET at a single centre between June 2007 and June 2020 were included. A nuclear medicine physician, blinded to patient outcomes, retrospectively reviewed imaging studies to assess for maximum tumour standardised uptake value (SUV) to mean liver SUV ratio (SUVTLR) and maximum porta hepatis SUV to mean liver SUV ratio (SUVPLR). ResultsBetween April 2007 and December 2020, a total of 204 patients underwent surgical intervention for PMP. Of these, 124 (60.8%) met the inclusion criteria. Median peritoneal carcinomatosis index for the entire cohort was 9 and complete cytoreduction (CC0/1) was achieved in 109 (88%) patients. Patients with high-grade PMP were more likely to have diffuse peritoneal disease (p < 0.001) and higher SUVTLR (p<0.001). The area under the ROC curve (AUC) of SUVTLR in predicting high-grade pathology was 71% (p = 0.003). Patients with a SUVTLR ≤ 0.78 had improved disease-free survival (p = 0.042). ConclusionPreoperative PET showed positive correlation with high-grade PMP and acceptable sensitivity and specificity as a diagnostic tool. PET should be considered a useful adjunct to standard imaging for predicting histological grade in the staging of patients with PMP.

Biomarker-Based Prediction of Longitudinal Tau Positron Emission Tomography in Alzheimer Disease

There is currently no consensus as to which biomarkers best predict longitudinal tau accumulation at different clinical stages of Alzheimer disease (AD). To describe longitudinal [18F]RO948 tau positron emission tomography (PET) findings across the clinical continuum of AD and determine which biomarker combinations showed the strongest associations with longitudinal tau PET and best optimized clinical trial enrichment. This longitudinal cohort study consecutively enrolled amyloid-β (Aβ)-negative cognitively unimpaired (CU) participants, Aβ-positive CU individuals, Aβ-positive individuals with mild cognitive impairment (MCI), and individuals with AD dementia between September 2017 and November 2020 from the Swedish BioFINDER-2 (discovery cohort) and BioFINDER-1 (validation cohort) studies. Baseline plasma and cerebrospinal fluid Aβ42/Aβ40, tau phosphorylated at threonine-217 (p-tau217), p-tau181 and neurofilament light, magnetic resonance imaging, amyloid PET ([18F]flutemetamol), and tau PET ([18F]RO948 in the BioFINDER-2 study; [18F]flortaucipir in the BioFINDER-1 study). Baseline tau PET standardized uptake value ratio (SUVR) and annual percent change in tau PET SUVR across regions of interest derived using a data-driven approach combining clustering and event-based modeling. Regression models were used to examine associations between individual biomarkers and longitudinal tau PET and to identify which combinations best predicted longitudinal tau PET. These combinations were then entered in a power analysis to examine how their use as an enrichment strategy would affect sample size in a simulated clinical trial. Of 343 participants, the mean (SD) age was 72.56 (7.24) years, and 157 (51.1%) were female. The clustering/event-based modeling-based approach identified 5 regions of interest (stages). In Aβ-positive CU individuals, the largest annual increase in tau PET SUVR was seen in stage I (entorhinal cortex, hippocampus, and amygdala; 4.04% [95% CI, 2.67%-5.32%]). In Aβ-positive individuals with MCI and with AD dementia, the greatest increases were seen in stages II (temporal cortical regions; 4.45% [95% CI, 3.41%-5.49%]) and IV (certain frontal regions; 5.22% [95% CI, 3.95%-6.49%]), respectively. In Aβ-negative CU individuals and those with MCI, modest change was seen in stage I (1.38% [95% CI, 0.78%-1.99%] and 1.80% [95% CI, 0.76%-2.84%], respectively). When looking at individual predictors and longitudinal tau PET in the stages that showed most change, plasma p-tau217 (R2 = 0.27, P < .005), tau PET (stage I baseline SUVR; R2 = 0.13, P < .05) and amyloid PET (R2 = 0.10, P < .05) were significantly associated with longitudinal tau PET in stage I in Aβ-positive CU individuals. In Aβ-positive individuals with MCI, plasma p-tau217 (R2 = 0.24, P < .005) and tau PET (stage II baseline SUVR; R2 = 0.44, P < .001) were significantly associated with longitudinal tau PET in stage II. Findings were replicated in BioFINDER-1 using longitudinal [18F]flortaucipir. For the power analysis component, plasma p-tau217 with tau PET resulted in sample size reductions of 43% (95% CI, 34%-46%; P < .005) in Aβ-positive CU individuals and of 68% (95% CI, 61%-73%; P < .001) in Aβ-positive individuals with MCI. In trials using tau PET as the outcome, plasma p-tau217 with tau PET may prove optimal for enrichment in preclinical and prodromal AD. However, plasma p-tau217 was most important in preclinical AD, while tau PET was more important in prodromal AD.

Excellent response to very-low-dose radiation (4 Gy) for indolent B-cell lymphomas: is 4 Gy suitable for curable patients?

Radiotherapy plays an important role in managing highly radiosensitive, indolent non-Hodgkin lymphomas, such as follicular lymphoma and marginal zone lymphoma. Although the standard of care for localized indolent non-Hodgkin lymphomas remains 24 Gy, de-escalation to very-low-dose radiotherapy (VLDRT) of 4 Gy further reduces toxicities and duration of treatment. Use of VLDRT outside palliative indications remains controversial; however, we hypothesize that it may be sufficient for most lesions. We present the largest single-institution VLDRT experience of adult patients with follicular lymphoma or marginal zone lymphoma treated between 2005 and 2018 (299 lesions; 250 patients) using modern principles including positron emission tomography staging and involved site radiotherapy. Outcomes include best clinical or radiographic response between 1.5 and 6 months after VLDRT and cumulative incidence of local progression (LP) with death as the only competing risk. After VLDRT, the overall response rate was 90% for all treated sites, with 68% achieving complete response (CR). With a median follow-up of 2.4 years, the 2-year cumulative incidence of LP was 25% for the entire cohort and 9% after first-line treatment with VLDRT for potentially curable, localized disease. Lesion size >6 cm was associated with lower odds of attaining a CR and greater risk of LP. There was no suggestion of inferior outcomes for potentially curable lesions. Given the clinical versatility of VLDRT, we propose to implement a novel, incremental, adaptive involved site radiotherapy strategy in which patients will be treated initially with VLDRT, reserving full-dose treatment for those who are unable to attain a CR.

18 F]FDG Positron Emission Tomography for Initial Staging and Healing Assessment at the End of Therapy in Lymph Nodes and Bone Tuberculosis.

Objective: In extra-pulmonary tuberculosis, therapeutic management is difficult in the absence of reliable tool to affirm healing at the end of treatment. In this prospective multicenter study, we evaluated [18F]FDG-PET for this purpose.Methods: Forty-two patients out of 55 included patients could be analyzed. Additionally to usual biological, histological and morphological explorations, [18F]FDG-PET was performed at diagnosis (PET1), at the end of treatment (PET2), indeed 6 months later. Then patients were followed until 12 months after end of prescribed treatment.Results: PET1 was positive in 97.6% of patients and discovered unknown injured sites in 52.7% of cases. PET2 was positive in 83.3% of uncured patients, and in 82.3% of cured patients. The sum and mean value of SUVmax measured in PET/CT lesions decreased between PET1 and PET2 in all patients. Mean value of SUVmax (MSUV) and sum value of SUVmax on PET2 showed the highest AUC on ROC curves for the diagnosis of healing at the end of prescribed treatment; MSUV 3.5 on PET2 had a sensitivity of 76.5% and a specificity of 80.0% to affirm healing at the end of prescribed treatment.Conclusions: [18F]FDG-PET/CT was useful at diagnosis, discovering unknown lesions in 52.7% of cases. MSUV on PET2 was the best criteria to affirm healing at the end of prescribed treatment.

Impact of Early Post-Transplant 5-Point Deauville Scale (18)F-FDG-PET Status on Survival Outcomes after Allogeneic Transplantation for Lymphoma

Background: Conversely to what has been reported for autotransplant,most studies have shown that pre-transplant Fluorine-18-fluorodeoxyglucose (FDG)-positron emission tomography (PET) status does not appear to predict survival after allogeneic stem cell transplantation (Allo-SCT) for lymphoma patients. However it is less clear what is the impact of early FDG-PET status on outcomes after Allo-SCT, especially when using Deauville 5-point scale (DS) which has become a standard of care for staging and re-staging of FDG-PET.Methods: This retrospective study included all lymphoma patients who underwent FDG PET before and/or early after Allo-SCT in our institution and who were alive at least 3 months after the graft. The primary objective was to study the impact on OS and LFS of pre-transplant (within 1 month) and early post-transplant (+3 months and within +6-9 months) FDG PET in these patients. All FDG-PET were reviewed by a nuclear medicine expert and restaging was performed according to 5-point DS. Two thresholds of positivity were used: a score of at least 3 (DS3, i.e. scores 3 - 5) and a score of at least 4 (DS4, i.e. score of 4 or 5).Results: Between April 2005 and December 2015, 103 patients fulfilled the inclusion criteria. There were 69 males (66%) and the median age was 51.6 years old (range: 22-67). Forty-seven patients had high-grade non-Hodgkin lymphoma (NHL), 6 low-grade NHL, 34 T-cell lymphoma and 16 Hodgkin lymphoma. Most patients were considered in complete remission at the time of transplant (n=56) and received a reduced-intensity conditioning regimen (n=90). The numbers of patients with available FDG PET before transplant, at 3 months and between 6-9 months post-transplant were 81, 93 and 61, respectively. Deauville FDG PET staging identified 29 DS3 and 20 DS4 patients before transplant, 28 DS3 and 20 DS4 at 3 months, and 25 DS3 and 18 DS4 between 6-9 months post-transplant, respectively.With a median follow-up of 49.5 months (range: 6-140.5) for alive patients, 3-year OS and LFS were 81% (71-87) and 65% (54-74) for the whole cohort, respectively. Twenty-six patients relapsed at a median time of 4.5 months (range: 2.9-15.9) from Allo-SCT.In univariate analysis, only the post-transplant FDG-PET status influenced outcomes. Factors associated with a lower OS were DS3 and DS4 scores at 3 months (HR: 2.25; 95%CI: 0.93-5.44, p=0.07 and HR: 3.00; 95%CI: 1.22-7.36, p=0.01, respectively) and a DS3 score between 6-9 months post-transplant (HR: 4.08; 95%CI: 1.00-16.55, p=0.04). Factors associated with a lower LFS were DS3 and DS4 scores at 3 months (HR: 2.64; 95%CI: 1.30-5.39, p=0.007 and HR: 3.86; 95%CI: 1.86-8.02, p=0.0003, respectively) as well as between 6-9 months (HR: 4.20; 95%CI: 1.26-13.98, p=0.01 and HR: 2.72; 95%CI: 0.86-8.60, p=0.08) post-transplant.In multivariate analysis, DS4 FDG-PET at 3 months was the only independent factor associated with lower OS (HR 2.8; 95%CI: 1.13-6.97), p=0.0269) and LFS (HR 2.44, 95%CI: 0.94-6.33, p=0.06).Total body CTscan evaluation was performed in 16/28 and 14/25 DS3 patients at 3 months and between 6-9 months post-transplant, respectively. At 3 months, all CT-scans were considered normal while 4/14 were considered positive between 6-9 months. Lymph nodes biopsies were performed for 8/25 DS3 patients at 3 months showing 6 lymphoma relapses (75%) and for 7/25 DS3 patients between 6-9 months post-transplant showing 2 lymphoma relapses (29%). Six patients received donor lymphocyte infusion between 3 to 9 months post-transplant, only 2 being guided by FDG-PET.Conclusion: A DS4 FDG-PET status at 3 months is highly predictive of survivals in lymphoma patients receiving an Allo-SCT and may help to guide strategies to prevent relapse. These results have to be validated prospectively. DisclosuresTouzeau:AbbVie: Research Funding. Moreau:Bristol-Myers Squibb: Honoraria; Onyx Pharmaceutical: Consultancy, Honoraria; Millennium: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene, Janssen, Takeda, Novartis, Amgen, Roche: Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria; Celgene: Consultancy, Honoraria; Amgen: Honoraria; Novartis: Consultancy, Honoraria.