18F-FDG-PET/CT for systemic staging of patients with newly diagnosed ER-positive and HER2-positive breast cancer

Joint EANM-SNMMI guideline on the role of 2-[18F]FDG PET/CT in no special type breast cancer : (endorsed by the ACR, ESSO, ESTRO, EUSOBI/ESR, and EUSOMA)

INTRODUCTION

There is much literature about the role of 2-[18F]FDG PET/CT in patients with breast cancer (BC). However, there exists no international guideline with involvement of the nuclear medicine societies about this subject.

PURPOSE

To provide an organized, international, state-of-the-art, and multidisciplinary guideline, led by experts of two nuclear medicine societies (EANM and SNMMI) and representation of important societies in the field of BC (ACR, ESSO, ESTRO, EUSOBI/ESR, and EUSOMA).

METHODS

Literature review and expert discussion were performed with the aim of collecting updated information regarding the role of 2-[18F]FDG PET/CT in patients with no special type (NST) BC and summarizing its indications according to scientific evidence. Recommendations were scored according to the National Institute for Health and Care Excellence (NICE) criteria.

RESULTS

Quantitative PET features (SUV, MTV, TLG) are valuable prognostic parameters. In baseline staging, 2-[18F]FDG PET/CT plays a role from stage IIB through stage IV. When assessing response to therapy, 2-[18F]FDG PET/CT should be performed on certified scanners, and reported either according to PERCIST, EORTC PET, or EANM immunotherapy response criteria, as appropriate. 2-[18F]FDG PET/CT may be useful to assess early metabolic response, particularly in non-metastatic triple-negative and HER2+ tumours. 2-[18F]FDG PET/CT is useful to detect the site and extent of recurrence when conventional imaging methods are equivocal and when there is clinical and/or laboratorial suspicion of relapse. Recent developments are promising.

CONCLUSION

2-[18F]FDG PET/CT is extremely useful in BC management, as supported by extensive evidence of its utility compared to other imaging modalities in several clinical scenarios.

Therapeutic impact of 18F-FDG PET/CT for initial staging in patients with clinical stage I and IIA, HER2-positive, or triple-negative breast cancer

PURPOSE

While 18F-FDG PET/CT (FDG-PET/CT) is consensual for clinical stage ≥ IIB breast cancers (BC), its benefit for stage I or IIA HER2+ or triple-negative breast cancer (TNBC) patients lacks sufficient evidence. We reported a single-institution, retrospective study evaluating FDG-PET/CT impact on patient management and staging for stage I or IIA HER2+ or Triple-Negative BC.

METHODS

Patients who underwent FDG-PET/CT staging before any treatment between January 2015 and December 2020 at Oscar Lambret Center were included.

EXCLUSIONS

patients with symptoms or conventional imaging suggestive of metastatic dissemination, or with prior malignancies. Initial stage was determined from mammography, breast ultrasound, breast MRI, and clinical examination. Staging and therapeutic impact based on FDG-PET/CT findings collected, including intra- (modification of dose/site/strategy in a type of management previously indicated) and inter-modality (modification of planned treatment strategy) changes.

RESULTS

The cohort included 287 female patients with clinical stage I or IIA, HER2+ , or TNBC. Therapeutic impact observed for 18% of patients (n = 52), with 2% (n = 7) undergoing inter-modality change with omission of planned surgery. The impact on patient management was higher for stage IIA patients (20%, 47/237) than for stage I patients (10%, 5/50). Among stage IIA disease, changes in management were more important for T2N0 patients (22%, 44/205) than for T1N1 patients (9%, 3/32). While not statistically significant, trends suggest usefulness of FDG-PET/CT for T2N0 patients.

CONCLUSION

Considering substantial therapeutic implications, our study suggests the usefulness of FDG-PET/CT for patients with stage IIA, HER2-positive, or Triple-Negative BC with tumor size > 2 cm (T2N0).

ACR Appropriateness Criteria® Imaging of Invasive Breast Cancer

As the proportion of women diagnosed with invasive breast cancer increases, the role of imaging for staging and surveillance purposes should be determined based on evidence-based guidelines. It is important to understand the indications for extent of disease evaluation and staging, as unnecessary imaging can delay care and even result in adverse outcomes. In asymptomatic patients that received treatment for curative intent, there is no role for imaging to screen for distant recurrence. Routine surveillance with an annual 2-D mammogram and/or tomosynthesis is recommended to detect an in-breast recurrence or a new primary breast cancer in women with a history of breast cancer, and MRI is increasingly used as an additional screening tool in this population, especially in women with dense breasts. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Quarter-Century Transformation of Oncology: Positron Emission Tomography for Patients with Breast Cancer

PET radiotracers have become indispensable in the care of patients with breast cancer. 18F-fluorodeoxyglucose has become the preferred method of many oncologists for systemic staging of breast cancer at initial diagnosis, detecting recurrent disease, and for measuring treatment response after therapy. 18F-Sodium Fluoride is valuable for detection of osseous metastases. 18F-fluoroestradiol is now FDA-approved with multiple appropriate clinical uses. There are multiple PET radiotracers in clinical trials, which may add utility of PET imaging for patients with breast cancer in the future. This article will describe the advances during the last quarter century in PET for patients with breast cancer.

Indicators describing the tumor lesion aggregation and dissemination and their impact on the prognosis of patients with diffuse large B cell lymphoma receiving chimeric antigen receptor T cell therapy

INTRODUCTION

Chimeric antigen receptor (CAR) T cell therapy has markedly improved the prognosis of patients with diffuse large B-cell lymphoma (DLBCL). The relative positioning of tumor lesions in lymphoma varies among patients, manifesting as either aggregation (clumped together) or dissemination (spread throughout the body). Prognostic significance of factors indicating the relative positioning of tumor lesions in CAR T cell therapy remains underexplored. For aggregation, prior research proposed the tumor volume surface ratio (TVSR), linking it to prognosis in chemotherapy. Regarding dissemination, indicators such as disease stage or extranodal involvement, commonly used in clinical practice, have not demonstrated prognostic significance in CAR T cell therapy. This study aims to analyze current indicators of tumor aggregation or dissemination and introduce a novel indicator to assess the prognostic value of tumor lesions' relative positioning in DLBCL patients undergoing CAR T cell therapy.

METHODS

This retrospective study included 42 patients receiving CAR T cell therapy. Lesion image information was obtained from the last PET/CT scan prior to CAR T cell infusion, including total metabolic tumor volume, total tumor surface, diameter of lymphoma masses, and the sites of tumor lesions. We evaluated TVSR and bulky disease as descriptors of tumor aggregation. We refined existing indicators, stage III&IV and >1 site extranodal involvement, to distill a new indicator, termed 'extra stage', to better represent tumor dissemination. The study examined the prognostic significance of tumor aggregation and dissemination.

RESULTS

Our findings indicate that TVSR, while prognostically valuable in chemotherapy, lacks practical prognostic value in CAR T cell therapy. Conversely, bulky disease emerged as an optimal prognostic indicator of tumor aggregation. Both bulky disease and extra stage were associated with poor prognosis and exhibiting synergistic prognostic impact in CAR T cell therapy.

CONCLUSIONS

Overall, the relative positioning of tumor lesions significantly influences the prognosis of patients with DLBCL receiving CAR T cell therapy. The ideal scenario involves tumors with minimal dissemination and no aggregation.

Women's Health Update: Growing Role of PET for Patients with Breast Cancer

Positron Emission Tomography (PET) has been growing in usage for patients with breast cancer, due to an increased number of FDA-approved PET radiotracers pertinent to patients with breast cancer as well as increased prospective evidence for the value of these agents. The leading PET radiotracer for patients with breast cancer is 18F-fluorodeoxyglucose (18F-FDG), which measures glucose metabolism. There is prospective evidence for the use of 18F-FDG PET in systemic staging of newly diagnosed locally advanced breast cancer (stages IIB-IIIC), monitoring breast cancer treatment response, and detecting breast cancer recurrence, particularly in no special type (NST) breast cancer. 16α-18F-fluoro-17β-Fluoroestradiol (18F-FES) is a radiolabeled estrogen which evaluates estrogen receptor (ER) accessible for estrogen binding. There is prospective evidence supporting 18F-FES PET as a predictive biomarker for selecting patients with metastatic breast cancer for endocrine therapies. 18F-FES PET has also been shown to be valuable in the evaluation of ER status of lesions which are difficult to biopsy, for evaluation of ER status in lesions that are equivocal on other imaging modalities, and for selecting optimal dosage of novel ER-targeted systemic therapies in early clinical trials. Multiple investigators have suggested 18F-FES PET will have an increasing role for patients with invasive lobular breast cancer (ILC), which is less optimally evaluated by 18F-FDG PET. Sodium 18F-Fluoride (18F-NaF) evaluates bone turnover and has been effective in evaluation of malignancies which commonly metastasize to bone. In patients with metastatic breast cancer, 18F-NaF PET/CT has demonstrated superior sensitivity for osseous metastases than 99mTc-MDP or CT. In addition to these three FDA-approved PET radiotracers, there are multiple novel radiotracers currently in clinical trials with potential to further increase PET usage for patients with breast cancer.

Imaging Molecular Targets and Metabolic Pathways in Breast Cancer for Improved Clinical Management: Current Practice and Future Perspectives

Breast cancer is the most frequently diagnosed cancer and leading cause of cancer-related deaths worldwide. Timely decision-making that enables implementation of the most appropriate therapy or therapies is essential for achieving the best clinical outcomes in breast cancer. While clinicopathologic characteristics and immunohistochemistry have traditionally been used in decision-making, these clinical and laboratory parameters may be difficult to ascertain or be equivocal due to tumor heterogeneity. Tumor heterogeneity is described as a phenomenon characterized by spatial or temporal phenotypic variations in tumor characteristics. Spatial variations occur within tumor lesions or between lesions at a single time point while temporal variations are seen as tumor lesions evolve with time. Due to limitations associated with immunohistochemistry (which requires invasive biopsies), whole-body molecular imaging tools such as standard-of-care [18F]FDG and [18F]FES PET/CT are indispensable in addressing this conundrum. Despite their proven utility, these standard-of-care imaging methods are often unable to image a myriad of other molecular pathways associated with breast cancer. This has stimulated interest in the development of novel radiopharmaceuticals targeting other molecular pathways and processes. In this review, we discuss validated and potential roles of these standard-of-care and novel molecular approaches. These approaches' relationships with patient clinicopathologic and immunohistochemical characteristics as well as their influence on patient management will be discussed in greater detail. This paper will also introduce and discuss the potential utility of novel PARP inhibitor-based radiopharmaceuticals as non-invasive biomarkers of PARP expression/upregulation.

Utility of positron emission tomography for determination of axillary metastasis of breast cancer

Objectives

The involvement of axillary lymph nodes plays a key role in breast cancer staging. Positron emission tomography is a promising modality for detecting axillary lymph node metastasis. In addition, nomograms are used to predict the status of axillary lymph nodes. In this study, the role of positron emission tomography in determining axillary metastasis and its correlation with the nomogram was evaluated.

Material and Methods

The axillary maximum standard uptake value (SUVmax) values of the patients in the preoperative period, the features in the perioperative and postoperative specimen and Memorial Sloan Kettering Cancer Center nomogram data were evaluated.

Results

As axillary SUVmax detected by Positron emission tomography in the preoperative period increased, so did the likelihood of lymph node involvement. Axillary SUVmax value were compared with Memorial Sloan Kettering Cancer Center nomogram data but no correlation was found. Age, lymph node number, histopathology results, mass diameter, presence or absence of lymphovascular invasion and/or perineural invasion, tumor type, estrogen receptor status, Ki67 and Cerb-B2 statuses were not correlated. However, axillary SUVmax was inversely correlated with grade and progesterone receptor status.

Conclusion

Results from positron emission tomography of axillary lymph nodes in breasts cancer patients showed that SUVmax was only inversely related to cancer grade and progesterone receptor status while not correlating with other accepted parameters for tumor assessment. Thus there is insufficient reliability for the use of axillary SUVmax alone for accurate assessment of tumor characteristics at present.

Breast Cancer Systemic Staging (Comparison of Computed Tomography, Bone Scan, and 18F-Fluorodeoxyglucose PET/Computed Tomography)

After an overview of the principles of bone scintigraphy, contrast-enhanced computed tomography (CE-CT) and 18F-fluorodeoxyglucose (FDG)-PET/CT, the advantages and limits of these modalities in the staging of breast cancer are discussed in this paper. CT and PET/CT are not optimal for delineating primary tumor volume, and PET is less efficient than the sentinel node biopsy to depict small axillary lymph node metastases. In large breast cancer tumor, FDG PET/CT is useful to show extra-axillary lymph nodes. FDG PET/CT is superior to bone scan and CE-CT in detecting distant metastases, and it results in a change of treatment plan in nearly 15% of patients.

Estrogen Receptor-Targeted and Progesterone Receptor-Targeted PET for Patients with Breast Cancer

Estrogen receptor (ER)-targeted imaging with 16α-18F-fluoro-17β-fluoroestradiol (18F-FES) has multiple proven clinical applications for patients with ER-positive breast cancer, including helping to select optimal patients for endocrine therapies, assessing ER status in lesions that are difficult to biopsy, and evaluating lesions with inconclusive results on other imaging tests. This has led to US Food and Drug Administration approval of 18F-FES PET for patients with ER-positive breast cancer. Newer progesterone receptor-targeted imaging agents are in clinical trials.

Breast Cancer and Physiologic Avidity From Breast Feeding on FDG PET/CT

ABSTRACT

A 35-year-old woman presented with breast cancer diagnosed during pregnancy. Eleven days after delivery, the patient underwent FDG PET/CT for systemic staging. Avidity was seen diffusely in both breasts, with a more avid focus at the site of a biopsy clip in the right breast. There were no lymph nodes or distant metastases. The patient was actively breast feeding, explaining the diffuse breast avidity. This case demonstrates both malignant and benign FDG avidity in the breasts at the same time, with a focal FDG-avid right breast malignancy identified among bilateral breast parenchyma with elevated physiologic FDG-avid secondary to breast feeding.

18F-FDG PET/CT radiomics signature and clinical parameters predict progression-free survival in breast cancer patients: A preliminary study

Introduction

This study aimed to investigate the feasibility of predicting progression-free survival (PFS) in breast cancer patients using pretreatment 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) radiomics signature and clinical parameters.

Methods

Breast cancer patients who underwent 18F-FDG PET/CT imaging before treatment from January 2012 to December 2020 were eligible for study inclusion. Eighty-seven patients were randomly divided into training (n = 61) and internal test sets (n = 26) and an additional 25 patients were used as the external validation set. Clinical parameters, including age, tumor size, molecularsubtype, clinical TNM stage, and laboratory findings were collected. Radiomics features were extracted from preoperative PET/CT images. Least absolute shrinkage and selection operators were applied to shrink feature size and build a predictive radiomics signature. Univariate and multivariate Cox proportional hazards models and Kaplan-Meier analysis were used to assess the association of rad-score and clinical parameter with PFS. Nomograms were constructed to visualize survival prediction. C-index and calibration curve were used to evaluate nomogram performance.

Results

Eleven radiomics features were selected to generate rad-score. The clinical model comprised three parameters: clinical M stage, CA125, and pathological N stage. Rad-score and clinical-model were significantly associated with PFS in the training set (P< 0.01) but not the test set. The integrated clinical-radiomics (ICR) model was significantly associated with PFS in both the training and test sets (P< 0.01). The ICR model nomogram had a significantly higher C-index than the clinical model and rad-score in the training and test sets. The C-index of the ICR model in the external validation set was 0.754 (95% confidence interval, 0.726–0.812). PFS significantly differed between the low- and high-risk groups stratified by the nomogram (P = 0.009). The calibration curve indicated the ICR model provided the greatest clinical benefit.

Conclusion

The ICR model, which combined clinical parameters and preoperative 18F-FDG PET/CT imaging, was able to independently predict PFS in breast cancer patients and was superior to the clinical model alone and rad-score alone.

Classifying Breast Cancer Metastasis Based on Imaging of Tumor Primary and Tumor Biology

The molecular classification of breast cancer has allowed for a better understanding of both prognosis and treatment of breast cancer. Imaging of the different molecular subtypes has revealed that biologically different tumors often exhibit typical features in mammography, ultrasound, and MRI. Here, we introduce the molecular classification of breast cancer and review the typical imaging features of each subtype, examining the predictive value of imaging with respect to distant metastases.

Lung Nodules Missed in Initial Staging of Breast Cancer Patients in PET/MRI-Clinically Relevant?

Simple Summary

Image-based primary staging in women with newly-diagnosed breast cancer is important to exclude distant metastases, which affect up to 10% of women. The increasing implementation of [¹⁸F]FDG-PET/MRI as a radiation-saving primary staging tool bears the risk of missing lung nodules. Thus, chest CT serves as the diagnostic of choice for the detection and classification of pulmonary nodules. The aim of this study was the evaluation of the clinical relevance of missed lung nodules at initial staging of breast cancer patients in [¹⁸F]FDG-PET/MRI compared with CT. We demonstrated in an homogeneous population of 152 patients that all patients with newly-diagnosed breast cancer and clinically-relevant lung nodules were detected at initial [¹⁸F]FDG-PET/MRI staging. However, due to the lower sensitivity of MRI in detecting lung nodules, a small proportion of clinically-relevant lung nodules were missed. Thus, a supplemental low-dose chest CT after neoadjuvant therapy should be considered for backup.

Abstract

Purpose: The evaluation of the clinical relevance of missed lung nodules at initial staging of breast cancer patients in [¹⁸F]FDG-PET/MRI compared with CT. Methods: A total of 152 patients underwent an initial whole-body [¹⁸F]FDG-PET/MRI and a thoracoabdominal CT for staging. Presence, size, shape and location for each lung nodule in [¹⁸F]FDG-PET/MRI was noted. The reference standard was established by taking initial CT and follow-up imaging into account (a two-step approach) to identify clinically-relevant lung nodules. Patient-based and lesion-based data analysis was performed. Results: No patient with clinically-relevant lung nodules was missed on a patient-based analysis with MRI VIBE, while 1/84 females was missed with MRI HASTE (1%). Lesion-based analysis revealed 4/96 (4%, VIBE) and 8/138 (6%, HASTE) missed clinically-relevant lung nodules. The average size of missed lung nodules was 3.2 mm ± 1.2 mm (VIBE) and 3.6 mm ± 1.4 mm (HASTE) and the predominant location was in the left lower quadrant and close to the hilum. Conclusion: All patients with newly-diagnosed breast cancer and clinically-relevant lung nodules were detected at initial [¹⁸F]FDG-PET/MRI staging. However, due to the lower sensitivity in detecting lung nodules, a small proportion of clinically-relevant lung nodules were missed. Thus, supplemental low-dose chest CT after neoadjuvant therapy should be considered for backup.

Molecular Imaging Assessment of Hormonally Sensitive Breast Cancer: An Appraisal of 2-[18F]-Fluoro-2-Deoxy-Glucose and Newer Non-2-[18F]-Fluoro-2-Deoxy-Glucose PET Tracers

Hormone-sensitive breast cancer, which demonstrates hormone receptor positivity, accounts for approximately 75% of newly diagnosed breast cancer. 2-[18F]-Fluoro-2-deoxy-glucose is the nonspecific radiotracer of glucose metabolism as opposed to specific receptor based tracers like 16α-[18F]-fluoro-17β-estradiol and [18F]-fluoro-furanyl-norprogesterone, which provide essential information about receptor status in the management of hormonally active malignancies. The complementary information provided by (a) 2-[18F]-fluoro-2-deoxy-glucose imaging for staging and prognostication along with (b) analyzing the hormonal receptor status with receptor-based PET imaging in breast cancer can optimize tumor characterization and influence patient management.

FDG-PET/CT for Primary Staging and Detection of Recurrence of Breast Cancer

Breast cancer is the most frequent cancer diagnosed in women worldwide. Accurate baseline staging is necessary to plan optimal breast cancer management. Early detection and staging of recurrence are also essential for optimal therapeutic management. Hybrid FDG-PET/CT imaging offers high sensitivity in detecting extra axillary lymph nodes and distant metastases. Although FDG-PET/CT has some limitations for low proliferative tumors, low-grade tumors and for well-differentiated luminal breast cancer, PET/CT is useful for the initial staging of breast cancer, regardless of tumor phenotype (luminal, triple negative, or HER2+) and of tumor grade. Although FDG-PET/CT performs better for invasive ductal carcinoma (invasive carcinoma of no specific subtype), it is also helpful for staging invasive lobular carcinomas. At initial staging, FDG-PET/CT becomes very useful for staging from clinical stage IIB (T2N1 or T3N0). FDG-PET/CT could be useful in patients with clinical stage IIA (T1N1 or T2N0), but there is not enough strong evidence to recommend routine use in this subgroup. For clinical stage I (T1N0) patients, FDG-PET/CT offers no added value. In patients with recurrent breast cancer, FDG-PET/CT is more effective than conventional imaging in detecting locoregional or distant recurrence, whether suspected by clinical examination, conventional imaging, or elevation of a tumor marker (CA 15.3 or CEA). PET/CT is effective even in the presence of normal tumor markers. PET/CT is also a powerful imaging modality for performing a whole-body workup of a known recurrence and for determining whether or not the recurrence is isolated.

A role of FDG-PET/CT for response evaluation in metastatic breast cancer?

Breast cancer prognosis is steadily improving due to early detection of primary cancer in screening programs and revolutionizing treatment development. In the metastatic setting, therapy improvements render breast cancer a chronic disease. Although FDG-PET/CT has emerged as a highly accurate method for staging metastatic breast cancer, there has been no change in response evaluation methods for decades. FDG-PET/CT has proven high prognostic values in patients with metastatic breast cancer when using quantitative PET methods. It has also shown a higher predictive value than conventional CT when applying the respective response evaluation criteria, RECIST and PERCIST. Response categorization using FDG-PET/CT is more sensitive in detecting progressive and regressive disease, while conventional imaging such as CT and bone scintigraphy deem stable disease more often. These findings reflect the higher accuracy of FDG-PET/CT for response evaluation in this patient group. But does the higher accuracy of FDG-PET/CT translate into a patient benefit when implementing it for monitoring response to palliative treatment? We have evidence of survival benefit from a retrospective study indicating the superiority of using FDG-PET/CT compared with conventional imaging for response evaluation in metastatic breast cancer patients. The survival benefit seems to result from earlier detection of progression with FDG-PET/CT than conventional imaging, leading to an earlier change in treatment with potentially better efficacy of the subsequent treatment line. FDG-PET/CT can be used semiquantitatively as suggested in PERCIST. However, we still need to improve clinically applicable methods based on neural network modeling to better integrate the quantitative information in a smart and standardized way, enabling relevant comparability between scans, patients, and institutions. Such innovation is warranted to support imaging specialists in diagnostic response assessment. Prospective multicenter studies analyzing patients' survival, quality of life, societal and patient costs of replacing conventional imaging with FDG-PET/CT are needed before firm conclusions can be drawn on which type of scan to recommend in future clinical guidelines.

Imaging for Radiation Planning in Breast Cancer

Radiation therapy is an integral component of the treatment of breast cancer. The indications and type of radiation therapy vary depending on disease invasiveness and stage. Imaging is the cornerstone for radiation therapy planning. While conventional imaging with CT remains the primary modality for radiation treatment planning locally in the breast, molecular imaging with [¹⁸F]FDG-PET/CT identifies additional occult disease that may help alter the local radiation therapy plan or treat oligometastatic disease. The ultimate effects on long-term outcomes remain to be determined. This article reviews the role of imaging in radiation planning for breast cancer.

Is there utility for fluorine-18-fluorodeoxyglucose positron-emission tomography scan before surgery in breast cancer? A 15-year overall survival analysis

BACKGROUND

The prognostic value of preoperative fluorine-18-fluorodeoxyglucose positron-emission tomography (¹⁸F-FDG PET) scan for determining overall survival (OS) in breast cancer (BC) patients is controversial.

AIM

To evaluate the OS predictive value of preoperative PET positivity after 15 years.

METHODS

We performed a retrospective search of the Universitair Ziekenhuis Brussel patient database for nonmetastatic patients who underwent preoperative PET between 2002-2008. PET positivity was determined by anatomical region of interest (AROI) findings for breast and axillary, sternal, and distant sites. The prognostic role of PET was examined as a qualitative binary factor (positive vs negative status) and as a continuous variable [maximum standard uptake value (SUVmax)] in multivariate survival analyses using Cox proportional hazards models. Among the 104 identified patients who received PET, 36 were further analyzed for the SUVmax in the AROI.

RESULTS

Poor OS within the 15-year study period was predicted by PET-positive status for axillary (P = 0.033), sternal (P = 0.033), and combined PET-axillary/sternal (P = 0.008) nodes. Poor disease-free survival was associated with PET-positive axillary status (P = 0.040) and combined axillary/sternal status (P = 0.023). Cox models confirmed the long-term prognostic value of combined PET-axillary/sternal status [hazard ratio (HR): 3.08, 95% confidence interval: 1.42-6.69]. SUVmax of ipsilateral breast and axilla as continuous covariates were significant predictors of long-term OS with HRs of 1.25 (P = 0.048) and 1.54 (P = 0.029), corresponding to relative increase in the risk of death of 25% and 54% per SUVmax unit, respectively. In addition, the ratio of the ipsilateral axillary SUVmax over the contralateral axillary SUVmax was the most significant OS predictor (P = 0.027), with 1.94 HR, indicating a two-fold relative increase of mortality risk.

CONCLUSION

Preoperative PET is valuable for prediction of long-term survival. Ipsilateral axillary SUVmax ratio over the uninvolved side represents a new prognostic finding that warrants further investigation.

Incidental liver lesions on baseline breast MRI: Outcomes on subsequent abdominal imaging

PURPOSE

To examine outcomes of incidental liver lesions on baseline breast magnetic resonance imaging (MRI) that were further evaluated with dedicated abdominal imaging.

METHODS

Consecutive breast MRI reports from 2011 to 2016 were retrospectively reviewed to identify incidental liver lesions. Only patients without prior breast MRI, without prior abdominal imaging, and with subsequent abdominal imaging were included. Patient demographics, breast MRI indication, and final liver lesion diagnosis were recorded.

RESULTS

Of 131 women (mean age 53.8 years), 94/131 (71.8%) underwent breast MRI for extent of disease evaluation, 25/131 (19.1%) for high-risk screening, 11/131 (8.4%) for implant evaluation, and 1/131 (0.8%) for problem-solving. Of 131 liver lesions (6-80 mm), 117/131 (89.3%) were deemed benign on subsequent abdominal imaging; 10/131 (7.6%) probably benign; and 4/131 lesions (3.1%) were confirmed breast cancer metastases. Metastatic liver lesions identified on breast MRI were more likely for women with a current diagnosis of breast cancer than for women without a current diagnosis of breast cancer: 4.3% vs 0%. Similarly, metastatic liver lesions identified on breast MRI were more likely for those with a higher prognostic stage (2 or 3) vs a lower prognostic stage (0 or 1) or no current breast cancer: 11.1% vs 0%.

CONCLUSION

Baseline breast MRIs showing incidental liver lesions showed unsuspected liver metastases only in women with a current diagnosis of clinical stage 2 or 3 breast cancer. This suggests breast MRI indication and clinical staging of current breast cancer, if present, can help plan management and decisions to obtain follow-up of liver lesions.

Impact on the long-term prognosis of FDG PET/CT in luminal-A and luminal-B breast cancer

PURPOSE

The aim of the present study was to explore the prognostic role of 2- deoxy-2-[18F]fluoro-D-glucose PET (FDG PET)/CT in recurrent luminal A and luminal B breast cancer.

MATERIALS AND METHODS

From two institutional databases, we retrospectively retrieved data about breast cancer patients undergoing FDG PET/CT between 2011 and 2018 for the assessment of recurrency. Molecular subtypes of breast cancer were defined based on the expression of estrogen, progesterone, human epidermal growth factor receptor 2 (HER2)-b receptors and proliferation index. Overall survival (OS, intended as the time from PET/CT and the time of death) was registered for each patient, by checking the medical charts. Parametric and survival analyses were computed.

RESULTS

Data of 179 patients were retrieved. Sixty-three patients had luminal A, 88 luminal B and 28 luminal B/He breast cancer. At the time of PET/CT scan, cancer antigen (CA) 15.3 levels was within the normal range in 119 patients, whereas it was increased in 60 patients. FDG PET/CT results were suggestive for disease recurrence in 114 (63.7%) patients. The median time lapse from the FDG PET/CT scan to the last clinical follow-up visit was 51 months (1-192 months). Patients with evidence of a PET/CT scan suggestive for disease recurrence showed a significantly shorter OS (P < 0.001) compared to patients with no PET/CT evidence of recurrence, in each subset of luminal breast cancer. Moreover, PET/CT was able to stratify the prognosis of patients independently from the level of tumor marker.

CONCLUSION

These data suggest that FDG PET/CT may be an attractive prognostic tool in recurrent breast cancer. Our study supports its prognostic role both in luminal A and B-type molecular subtypes, regardless of the CA 15.3 levels.

Breast cancer: initial workup and staging with FDG PET/CT

Purpose

Precise staging is needed to plan optimal management in breast cancer. 18F-fluorodeoxyglucose positron emission tomography coupled with computed tomography (FDG-PET/CT) offers high sensitivity in detecting extra axillary lymph nodes and distant metastases. This review aims to clarify in which groups of patients staging with FDG-PET/CT would be beneficial and should be offered. We also discuss how tumor biology and breast cancer subtypes should be taken into account when interpreting FDG-PET/CT scans.

Methods

We performed a comprehensive literature review and rigorous appraisal of research studies assessing indications for FDG-PET/CT in breast cancer. This assessment regarding breast cancer served as a basis for the recommendations set by a working group of the French Society of Nuclear Medicine, in collaboration with oncological societies, for developing good clinical practice recommendations on the use of FDG-PET/CT in oncology.

Results

FDG-PET/CT is useful for initial staging of breast cancer, independently of tumor phenotype (triple negative, luminal or HER2 +) and regardless of tumor grade. Considering histological subtype, FDG-PET/CT performs better for staging invasive ductal carcinoma, although it is also helpful for staging invasive lobular carcinomas. Based on the available data, FDG-PET/CT becomes useful for staging starting from clinical stage IIB. FDG-PET/CT is possibly useful in patients with clinical stage IIA (T1N1 or T2N0), but there is not enough strong data to recommend routine use in this subgroup. For clinical stage I (T1N0) patients, staging with FDG-PET/CT offers no added value.

Conclusion

FDG-PET/CT is useful for staging patients with breast cancer, starting from clinical stage IIB.

Impact of 18F-FDG PET, PET/CT, and PET/MRI on Staging and Management as an Initial Staging Modality in Breast Cancer: A Systematic Review and Meta-analysis

OBJECTIVES

We performed a systematic review and meta-analysis to evaluate the impact of 18F-FDG PET, PET/CT, and PET/MRI on staging and management during the initial staging of breast cancer.

METHODS

We searched the PubMed, Embase, Cochrane Library, and KoreaMed databases until March 2020 to identify studies that reported the proportion of breast cancer patients whose clinical stage or management were changed after PET scans. The proportion of changes was pooled using a random-effects model. Subgroup and metaregression analyses were performed to explore heterogeneity.

RESULTS

We included 29 studies (4276 patients). The pooled proportions of changes in stage and management were 25% (95% confidence interval [CI], 21%-30%) and 18% (95% CI, 14%-23%), respectively. When stage changes were stratified according to initial stage, the pooled proportions were 11% (95% CI, 3%-22%) in stage I, 20% (95% CI, 16%-24%) in stage II, and 34% (95% CI, 27%-42%) in stage III. The relative proportions of intermodality and intention-to-treat changes were 74% and 70%, respectively. Using metaregression analyses, the mean age and the proportion of initial stage III to IV and histologic grade II to III were significant factors affecting the heterogeneity in changes in stage or management.

CONCLUSIONS

Currently available literature suggests that the use of 18F-FDG PET, PET/CT, or PET/MRI leads to significant modification of staging and treatment in newly diagnosed breast cancer patients. Therefore, there may be a role for routine clinical use of PET imaging for the initial staging of breast cancer.

Diagnostic Performance of F18-FDG PET/CT in Male Breast Cancers Patients

INTRODUCTION

F18-FDG PET/CT is the most important hybrid imaging used in the diagnostic, staging, follow-up, and treatment evaluation response in cancer patients. However, it is well-known that in breast cancer the use of F18-FDG is not included in the first line protocol of initial diagnostic, both in female and male breast cancer patients. F18-FDG PET/CT is a valuable tool to provide information on extra-axillary lymph node involvement, distant metastases, and other occult primary cancers. This study assesses F18-FDG PET/CT systemic staging in male patients with diagnosed breast cancer and determines detection rates for unsuspected distant metastases and synchronous malignancies.

METHODS

We analyzed a number of 170 male patients with breast cancer, seen between 2000-2020, in a tertiary center. From this group, between 2013-2020 a number of 23 patients underwent F18-FDG PET/CT. Rates of upstaging were determined for each case and the detection of other primary malignancies was analyzed.

RESULTS

Median age of male breast cancer group was 61.3 y (range, 34-85 y), most had intraductal carcinoma (82.4%) and unsuspected distant metastases, which increased patient stage to IV, observed in 27%. In 4 out 23 patients (17.4%), F18-FDG PET/CT identified synchronous cancers (2 prostate cancers, 1 thyroid and 1 colon cancer).

CONCLUSION

F18-FDG PET/CT is a valuable tool to provide information on extra-axillary lymph node involvement, distant metastases, and other occult primary cancers. Baseline F18-FDG PET/CT has a substantial impact on the initial staging and on clinical management in male breast patients and should be considered for use in newly diagnosed patients.

Value of pretreatment 18F-FDG PET/CT in prognosis and the reflection of tumor burden: a study in pediatric patients with newly diagnosed neuroblastoma

Fluorine-18 fluorodeoxyglucose (18F-FDG) PET/CT has been commonly used in pediatric patients with newly diagnosed neuroblastoma (NB) for diagnosis. We retrospectively reviewed 40 pediatric patients with newly diagnosed NB who underwent 18F-FDG PET/CT. Clinicopathological factors and metabolic parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on PET/CT were evaluated as predictive factors for progression-free survival (PFS) and overall survival (OS) by univariate and multivariate analysis. Spearman rank correlation analyses were used to estimate the correlations between clinical factors and PET findings. The mean follow-up after 18F-FDG-PET/CT was 32.9 months. During the follow-up period 15 (37.5%) patients experienced progression, and 9 (22.5%) died. MTV (P=0.001) and TLG (p=0.004) remained significant predictive factors for tumor progression, along with lactate dehydrogenase (LDH), neuron-specific enolase (NSE) and bone metastasis. Univariate analysis showed that bone metastasis, LDH (>1064 IU/L), NSE (>364.4 ug/L), MTV (>191 cm3) and TLG (>341.41 g) correlated with PFS, and LDH (>1064 IU/L), NSE (>364.4 ug/L) and MTV (>191 cm³) correlated with OS (p<0.05). In multivariate analysis, MTV and bone metastasis were independent prognostic factors for PFS (p=0.001 and 0.023, respectively), and MTV remained the only independent prognostic factor for OS (p= 0.004). We also found that there were correlations between semiquantitative PET/CT parameters and clinical features in NB. Our results suggested that 18F-FDG PET/CT was a useful tool to predictive progression and to reflect tumor burden for patients with NB.

Prospective evaluation of whole-body MRI and 18F-FDG PET/MRI in N and M staging of primary breast cancer patients

OBJECTIVES

To evaluate and compare the diagnostic potential of whole-body MRI and whole-body 18F-FDG PET/MRI for N and M staging in newly diagnosed, histopathologically proven breast cancer.

MATERIAL AND METHODS

A total of 104 patients (age 53.4 ± 12.5) with newly diagnosed, histopathologically proven breast cancer were enrolled in this study prospectively. All patients underwent a whole-body 18F-FDG PET/MRI. MRI and 18F-FDG PET/MRI datasets were evaluated separately regarding lesion count, lesion localization, and lesion characterization (malignant/benign) as well as the diagnostic confidence (5-point ordinal scale, 1-5). The N and M stages were assessed according to the eighth edition of the American Joint Committee on Cancer staging manual in MRI datasets alone and in 18F-FDG PET/MRI datasets, respectively. In the majority of lesions histopathology served as the reference standard. The remaining lesions were followed-up by imaging and clinical examination. Separately for nodal-positive and nodal-negative women, a McNemar chi2 test was performed to compare sensitivity and specificity of the N and M stages between 18F-FDG PET/MRI and MRI. Differences in diagnostic confidence scores were assessed by Wilcoxon signed rank test.

RESULTS

MRI determined the N stage correctly in 78 of 104 (75%) patients with a sensitivity of 62.3% (95% CI: 0.48-0.75), a specificity of 88.2% (95% CI: 0.76-0.96), a PPV (positive predictive value) of 84.6% % (95% CI: 69.5-0.94), and a NPV (negative predictive value) of 69.2% (95% CI: 0.57-0.8). Corresponding results for 18F-FDG PET/MRI were 87/104 (83.7%), 75.5% (95% CI: 0.62-0.86), 92.2% (0.81-0.98), 90% (0.78-0.97), and 78.3% (0.66-0.88), showing a significantly better sensitivity of 18F-FDG PET/MRI determining malignant lymph nodes (p = 0.008). The M stage was identified correctly in MRI and 18F-FDG PET/MRI in 100 of 104 patients (96.2%). Both modalities correctly staged all 7 patients with distant metastases, leading to false-positive findings in 4 patients in each modality (3.8%). In a lesion-based analysis, 18F-FDG PET/MRI showed a significantly better performance in correctly determining malignant lesions (85.8% vs. 67.1%, difference 18.7% (95% CI: 0.13-0.26), p < 0.0001) and offered a superior diagnostic confidence compared with MRI alone (4.1 ± 0.7 vs. 3.4 ± 0.7, p < 0.0001).

CONCLUSION

18F-FDG PET/MRI has a better diagnostic accuracy for N staging in primary breast cancer patients and provides a significantly higher diagnostic confidence in lesion characterization than MRI alone. But both modalities bear the risk to overestimate the M stage.

Progress and Future Trends in PET/CT and PET/MRI Molecular Imaging Approaches for Breast Cancer

Breast cancer is a major disease with high morbidity and mortality in women worldwide. Increased use of imaging biomarkers has been shown to add more information with clinical utility in the detection and evaluation of breast cancer. To date, numerous studies related to PET-based imaging in breast cancer have been published. Here, we review available studies on the clinical utility of different PET-based molecular imaging methods in breast cancer diagnosis, staging, distant-metastasis detection, therapeutic and prognostic prediction, and evaluation of therapeutic responses. For primary breast cancer, PET/MRI performed similarly to MRI but better than PET/CT. PET/CT and PET/MRI both have higher sensitivity than MRI in the detection of axillary and extra-axillary nodal metastases. For distant metastases, PET/CT has better performance in the detection of lung metastasis, while PET/MRI performs better in the liver and bone. Additionally, PET/CT is superior in terms of monitoring local recurrence. The progress in novel radiotracers and PET radiomics presents opportunities to reclassify tumors by combining their fine anatomical features with molecular characteristics and develop a beneficial pathway from bench to bedside to predict the treatment response and prognosis of breast cancer. However, further investigation is still needed before application of these modalities in clinical practice. In conclusion, PET-based imaging is not suitable for early-stage breast cancer, but it adds value in identifying regional nodal disease and distant metastases as an adjuvant to standard diagnostic imaging. Recent advances in imaging techniques would further widen the comprehensive and convergent applications of PET approaches in the clinical management of breast cancer.

Baseline staging imaging for distant metastasis in women with stages I, II, and III breast cancer

Background

In Ontario, there is no clearly defined standard of care for staging for distant metastasis in women with newly diagnosed and biopsy-confirmed breast cancer whose clinical presentation is suggestive of early-stage disease. This guideline addresses baseline imaging investigations for women with newly diagnosed primary breast cancer who are otherwise asymptomatic for distant metastasis.

Methods

The medline and embase databases were systematically searched for evidence from January 2000 to April 2019, and the best available evidence was used to draft recommendations relevant to the use of baseline imaging investigation in women with newly diagnosed primary breast cancer who are otherwise asymptomatic. Final approval of this practice guideline was obtained from both the Staging in Early Stage Breast Cancer Advisory Committee and the Report Approval Panel of the Program in Evidence-Based Care.

Recommendations

These recommendations apply to all women with newly diagnosed primary breast cancer (originating in the breast) who have no symptoms of distant metastasis Staging tests using conventional anatomic imaging [chest radiography, liver ultrasonography, chest-abdomen-pelvis computed tomography (ct)] or metabolic imaging modalities [integrated positron-emission tomography (pet)/ct, integrated pet/magnetic resonance imaging (mri), bone scintigraphy] should not be routinely ordered for women newly diagnosed with clinical stage i or stage ii breast cancer who have no symptoms of distant metastasis, regardless of biomarker status. In women newly diagnosed with stage iii breast cancer, baseline staging tests using either anatomic imaging (chest radiography, liver ultrasonography, chest-abdomen-pelvis ct) or metabolic imaging modalities (pet/ct, pet/mri, bone scintigraphy) should be considered regardless of whether the patient is symptomatic for distant metastasis and regardless of biomarker profile.

Patient Repositioning Reveals a Malignant Pleura Effusion Initially Mistaken as a Bone Metastasis on 18FDG PET/CT

A 70-year-old woman with breast cancer underwent F-FDG PET/CT for restaging. An FDG-avid focus corresponding to a rib on CT images was identified and interpreted as suggestive of an osseous metastasis. A PET/CT-guided biopsy was planned with the patient in prone position. Prone images demonstrated the FDG focus "moved" to the anterior chest and corresponding to pleural fluid. The diagnosis was altered from osseous metastases to pleural malignancy, and the bone biopsy was not performed. This case not only emphasizes the sensitivity of PET in the detection of malignancy, but also highlights the difficulty localizing small, mobile, FDG-avid foci.

18F-FES PET/CT Influences the Staging and Management of Patients with Newly Diagnosed Estrogen Receptor-Positive Breast Cancer: A Retrospective Comparative Study with 18F-FDG PET/CT

PURPOSE

We compared the clinical value of 16a-18F-fluoro-17b-estradiol (¹⁸F-FES) positron emission tomography (PET)/computed tomography (CT) and ¹⁸F-fluoro-2-deoxy-D-glucose (¹⁸F-FDG) PET/CT and investigated whether and how ¹⁸F-FES PET/CT affects the implemented management of newly diagnosed estrogen receptor positive breast cancer patients.

MATERIALS AND METHODS

We retrospectively analyzed 19 female patients newly diagnosed with immunohistochemistry-confirmed estrogen receptor (ER)-positive breast cancer who underwent ¹⁸F-FES and ¹⁸F-FDG PET/CT within 1 week in our center. The sensitivity of ¹⁸F-FES and ¹⁸F-FDG in diagnosed lesions were compared. To investigate the definite clinical impact of ¹⁸F-FES on managing patients with newly diagnosed ER positive breast cancer, we designed two kinds of questionnaires. Referring physicians completed the first questionnaire based on the ¹⁸F-FDG report to propose the treatment regime, and the second was completed immediately after reviewing the imaging report of ¹⁸F-FES to indicate intended management changes.

RESULTS

In total, 238 lesions were analyzed in 19 patients with newly diagnosed ER-positive breast cancer. Lesion detection was achieved in 216 sites with ¹⁸F-FES PET and in 197 sites with ¹⁸F-FDG PET/CT. These results corresponded to sensitivities of 90.8% for ¹⁸F-FES versus 82.8% for ¹⁸F-FDG PET/CT in diagnosed lesions. Thirty-five physicians were given the questionnaires referring to the treatment strategy, with 27 of them completing both questionnaires. The application of ¹⁸F-FES in addition to ¹⁸F-FDG PET/CT changed the management in 26.3% of the 19 patients with newly diagnosed ER-positive breast cancer.

CONCLUSION

Performing ¹⁸F-FES PET/CT in newly diagnosed ER-positive breast cancer patients increases the value of diagnosis equivocal lesions and treatment management compared with ¹⁸F-FDG PET/CT.

IMPLICATIONS FOR PRACTICE

This study investigated whether 16a-18F-fluoro-17b-estradiol (¹⁸F-FES) positron emission tomography (PET)/computed tomography (CT) affects the clinical management of patients with newly diagnosed estrogen receptor (ER)-positive breast cancer. Physicians completing two questionnaires comparing the clinical impact of 18F-FES and 18F-FDG on individual management plans in patients with newly diagnosed ER-positive breast cancer confirmed that 18F-FES scans led to change in management in 26.3% of the 19 patients with newly diagnosed ER positive breast cancer. This retrospective study indicates the potential impact of 18F-FES PET/CT on intended management of patients with newly diagnosed estrogen receptor positive breast cancer in comparison to 18F-fluoro-2-deoxy-D-glucose PET/CT.

Diagnostic efficacy of PET/CT in bone tumors

Clinical value of PET/CT (positron emission tomography/computed tomography) in the diagnosis of malignant bone tumors (BT) was investigated. Fifty-four patients with BT were first diagnosed by ordinary CT and then by PET/CT. The diagnostic efficacy outcomes and diagnosis of malignant BT by clinical stage of the two methods for BT were observed and recorded, and the diagnostic value of PET/CT in the diagnosis of BT was evaluated. There were 14 cases of benign BT patients, 15 cases of stage I, 10 cases of stage II and 15 cases of stage III in malignant BT patients. The diagnostic coincidence rate of PET/CT was 92.59% and the diagnostic coincidence rate of CT was 72.22%, which showed that the diagnostic coincidence rate of PET/CT was significantly higher than that of CT (P<0.05). The sensitivity, negative predictive value and positive predictive value of PET/CT were 95.00, 85.71 and 95.00%, respectively, which were higher than those of CT (P<0.05). CT and PET/CT were used for the clinical staging and pathological diagnosis of malignant BT; the results showed that the diagnostic accuracy of PET/CT in the clinical stages of malignant BT was also significantly higher than that of CT (P<0.05). The diagnostic efficacy of PET/CT in BT is better than that in CT. PET/CT can diagnose the pathological properties of BT more accurately, and can also effectively diagnose the clinical stage of malignant BT and provide clinical diagnostic basis for follow-up procedures.

18F-FDG PET/CT for Systemic Staging of Newly Diagnosed Breast Cancer in Men

¹⁸F-FDG PET/CT has demonstrated substantial value in systemic staging of newly diagnosed breast cancer in women. However, it is not known whether breast cancer in male patients benefits similarly. This study assesses ¹⁸F-FDG PET/CT systemic staging in patients with newly diagnosed male breast cancer and determines detection rates for unsuspected distant metastases stratified by pre-PET/CT stage. Methods: In this Institutional Review Board-approved retrospective study, our Health Care Information System was screened for stage I-III male patients with breast cancer who underwent ¹⁸F-FDG PET/CT before systemic or radiation therapy from 2004 to 2017. Initial stage was determined by mammography, ultrasound, or surgery. ¹⁸F-FDG PET/CT was evaluated to identify unsuspected extraaxillary regional nodal and distant metastases, and a post-PET/CT stage was determined. Rates of upstaging to stage IV were determined for each initial stage. Results: During the 14-y period, 10,124 unique patients underwent ¹⁸F-FDG PET/CT for breast cancer at our institution. Of these, 106 patients were men, and 39 of these patients were imaged at initial staging and met the inclusion criteria. Median age was 62 y (range, 31-90 y), most had ductal carcinoma (95%), and most were estrogen receptor-positive (97%). In 7 of 39 patients (18%), ¹⁸F-FDG PET/CT identified previously unsuspected distant metastases, which increased patient stage to IV. This included 3 of 19 (16%) initial stage IIB patients and 4 of 12 (33%) initial stage III patients. ¹⁸F-FDG PET/CT also detected an unsuspected synchronous lymphoma in 1 patient. Conclusion: ¹⁸F-FDG PET/CT revealed previously unsuspected distant metastases in 16% of male patients with pre-PET/CT stage IIB breast cancer and 33% of those with stage III breast cancer. These rates are comparable to previously published upstaging rates in female patients. ¹⁸F-FDG PET/CT demonstrates value for systemic staging of male patients with breast cancer and should be considered for use in newly diagnosed patients, particularly those with stage IIB and III disease.

Trends in oncologic hybrid imaging

Hybrid imaging plays a central role in the diagnosis and management of a wide range of malignancies at all stages. In this article, we review the most pertinent historical developments, emerging clinical applications of novel radiotracers and imaging technologies, and potential implications for training and practice. This includes an overview of novel tracers for prostate, breast, and neuroendocrine tumors, assessment of tumor heterogeneity, the concept of image-guided ‘biologically relevant dosing’, and theranostic applications. Recent technological advancements, including time-of-flight PET, PET/MRI, and ‘one-minute whole-body PET’, are also covered. Finally, we discuss how these rapidly evolving applications might affect current training curricula and how imaging-derived big data could be harnessed to the benefit of our patients.

Preoperative [18]fluorodeoxyglucose-positron emission tomography/computed tomography in early stage breast cancer: Rates of distant metastases

AIM

To investigate rates of distant metastases (DM) detected with [18]fluorodeoxyglucose-positron emission tomography/computed tomography (18FDG-PET/CT) in early stage invasive breast cancer.

METHODS

We searched the English language literature databases of PubMed, EMBASE, ISI Web of Knowledge, Web of Science and Google Scholar, for publications on DM detected in patients who had 18FDG-PET/CT scans as part of the staging for early stages of breast cancer (stage I and II), prior to or immediately following surgery. Reports published between 2011 and 2017 were considered. The systematic review was conducted according to the PRISMA guidelines.

RESULTS

Among the 18 total studies included in the analysis, the risk of DM ranged from 0% to 8.3% and 0% to 12.9% for stage I and II invasive breast cancer, respectively. Among the patients with clinical stage II, the rate of occult metastases diagnosed by 18FDG-PET/CT was 7.2% (range, 0%-19.6%) for stage IIA and 15.8% (range, 0%-40.8%) for stage IIB. In young patients (< 40-year-old), 18FDG-PET/CT demonstrated a higher prevalence of DM at the time of diagnosis for those with aggressive histology (i.e., triple-negative receptors and poorly differentiated grade).

CONCLUSION

Young patients with poorly differentiated tumors and stage IIB triple-negative breast cancer may benefit from 18FDG-PET/CT at initial staging to detect occult DM prior to surgery.