Computed Diffusion-Weighted Images of Rectal Cancer: Image Quality, Restaging, and Treatment Response after Neoadjuvant Therapy.

BACKGROUND: Computed diffusion-weighted images (cDWI) of random b value could be derived from acquired DWI (aDWI) with at least two different b values. However, its comparison between aDWI and cDWI images in locally advanced rectal cancer (LARC) patients after neoadjuvant therapy (NT) is needed. PURPOSE: To compare the cDWI and aDWI in image quality, restaging, and treatment response of LARC after NT. STUDY TYPE: Retrospective. POPULATION: Eighty-seven consecutive patients. FIELD STRENGTH/SEQUENCE: 3.0 T/DWI. ASSESSMENT: All patients underwent two DWI sequences, including conventional acquisition with b = 0 and 1000 s/mm2 (aDWIb1000 ) and another with b = 0 and 700 s/mm2 on a 3.0-T MR scanner. The images of the latter were used to compute the diffusion images with b = 1000 s/mm2 (cDWIb1000 ). Four radiologists with 3, 4, 14, and 25 years of experience evaluated the images to compare the image quality, TN restaging performance, and treatment response between aDWIb1000 and cDWIb1000 . STATISTICAL TESTS: Interclass correlation coefficients, weighted κ coefficient, paired Wilcoxon, and McNemar or Fisher test were used. A significance level of 0.05 was used. RESULTS: The cDWIb1000 images were superior to the aDWIb1000 ones in both subjective and objective image quality. In T restaging, the overall diagnostic accuracy of cDWIb1000 images was higher than that of aDWIb1000 images (57.47% vs. 49.43%, P = 0.289 for the inexperienced radiologist; 77.01% vs. 63.22%, significant for the experienced radiologist), with better sensitivity in determining ypT0-Tis tumors. Additionally, it increased the sensitivity in detecting ypT2 tumors for the inexperienced radiologist and ypT3 tumors for the experienced radiologist. N restaging and treatment response were found to be similar between two sequences for both radiologists. DATA CONCLUSION: Compared to aDWIb1000 images, the computed ones might serve as a wise approach, providing comparable or better image quality, restaging performance, and treatment response assessment for LARC after NT. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2.

PSMA PET/CT: joint EANM procedure guideline/SNMMI procedure standard for prostate cancer imaging 2.0.

Here we aim to provide updated guidance and standards for the indication, acquisition, and interpretation of PSMA PET/CT for prostate cancer imaging. Procedures and characteristics are reported for a variety of available PSMA small radioligands. Different scenarios for the clinical use of PSMA-ligand PET/CT are discussed. This document provides clinicians and technicians with the best available evidence, to support the implementation of PSMA PET/CT imaging in research and routine practice.

How reliable is restaging MRI after neoadjuvant therapy in rectal cancer?

BACKGROUND: Despite the pivotal role of magnetic resonance imaging (MRI) in rectal cancer staging and evaluation, the reliability of restaging MRI after neoadjuvant therapy is still debatable. This study aimed to assess the accuracy of restaging MRI by comparing post-neoadjuvant MRI findings with those of the final pathology. METHODS: This study was a retrospective review of the medical records of adult rectal cancer patients who had restaging MRI following neoadjuvant therapy and prior to rectal cancer resection in a NAPRC-certified rectal cancer centre between 2016 and 2021. The study compared findings of preoperative, post-neoadjuvant MRI with final pathology relative to T stage, N stage, tumour size, and circumferential resection margin (CRM) status. RESULTS: A total of 126 patients were included in the study. We found fair concordance (kappa -0.316) for T stage between restaging MRI and pathology report, and slight concordance for N stage and CRM status (kappa -0.11, kappa = 0.089, respectively). Concordance rates were lower for patients following total neoadjuvant treatment (TNT) or with a low rectal tumour. In total, 73% of patients with positive N pathology status had negative N status in the restaging MRI. Sensitivity and specificity regarding positive CRM in post-neoadjuvant treatment MRI were 45.45% and 70.4%, respectively. CONCLUSION: We found low concordance levels between restaging MRI and pathology regarding TN stage and CRM status. Concordance levels were even lower for patients after TNT regimen and with a low rectal tumour. In the era of TNT and watch-and-wait approach, we should not rely solely on restaging MRI to make post-neoadjuvant treatment decisions.

[The impact of restaging transurethral resection on recurrence and progression free survival in patients with T1 high grade bladder cancer]. / Résultats et impacts d'une résection de réévaluation dans le traitement des carcinomes urothéliaux de vessie pT1G3 : étude observationnelle.

INTRODUCTION: Restaging transurethral resection (re-TUR) of high grade T1 bladder cancer (HGT1-BC) is recommended but the impact in terms of recurrence-free survival (RFS) and progression-free survival (PFS) is discussed. The objective of this study was to evaluate our practice of re-TUR for these tumors and its impact on overall survival (OS), RFS and PFS. MATERIALS AND METHODS: A retrospective observational study was conducted between 2010 and 2020. The inclusion criteria was the presence of newly diagnosed HGT1-BC. Patients with incomplete resection, suspicion of infiltrating tumor, upper tract urothelial cancer, or metastatic disease were ineligible. Two groups were defined : Group 1 with re-TUR and Group 2 without re-TUR. RFS and PFS were evaluated. RESULTS: A total of 78 patients were included, including 50 (64,1%) in group 1. There were no significant differences between the two groups. The mean time to re-TUR was 8 weeks and 60% residual tumor was found. Initial under-staging was found in 12% of cases. RFS and PFS were significantly better in Group 1 (P=0.0019; P=0,02). No significant were found between the groups in OS and specific survival (SS). CONCLUSION: Performing a re-TUR for high grade T1 bladder tumors allows detection of residual tumor and decreases the risk of under-evaluation. It is associated with a significant improvement in RFS and PFS with no impact on OS and SS.

Role of 18F-fluorodeoxyglucose positron-emission tomography/computed tomography in restaging of adrenocortical carcinoma.

Background: The objective was to retrospectively evaluate the contribution of fluorodeoxyglucose [18F] positron emission tomography/computed tomography (18FDG-PET/CT) to the re-staging of adrenocortical carcinoma (ACC). Materials and methods: A total of 16 patients (10 males and 6 females), who underwent adrenalectomy due to adrenocortical carcinoma and 18FDG-PET/CT scan to re-stage the tumor between July 2007 and April 2013, were included in the present study. The mean age was 53.37 ± 13.91 years (min: 30, max: 74) The patients were required to fast for six hours prior to scanning, and whole-body PET scanning from the skull base to the upper thighs was performed approximately 1 h after the intravenous injection of 555 MBq of F-18 FDG. Whole body CT scanning was performed in the cranio-caudal direction. FDG-PET images were reconstructed using CT data for attenuation correction. Suspicious recurrent or metastatic lesions were confirmed by histopathology or clinical follow-up. Results: Sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18FDG-PET/CT were 100%, 83.3%, 90.9%, 83.3%, and 93.7%, respectively. Conclusion: 18FDG-PET/CT detects local recurrence and/or distant metastases with high accuracy in the re-staging of operated adrenocortical carcinoma. It is considered that the procedure could play an important role in treatment decision after the operation and post-operative follow-up and could influence the entire decision-making process.

Establishment and validation of nomograms for predicting mesorectal lymph node staging and restaging.

BACKGROUND: Preoperative determination of lymph node (LN) status is crucial in treatment planning for rectal cancer. This study prospectively evaluated the risk factors for lymph node metastasis (LNM) at staging and restaging based on a node-by-node pairing between MRI imaging findings and histopathology and constructed nomograms to evaluate its diagnostic value. METHODS: From July 2021 to July 2022, patients with histopathologically verified rectal cancer who underwent MRI before surgery were prospectively enrolled. Histological examination of each LN status in the surgical specimens and anatomical matching with preoperative imaging. Taking histopathological results as the gold standard, federating clinical features from patients and LN imaging features on MRI-T2WI. Risk factors for LN metastasis were identified by multivariate logistic regression analysis and used to create a nomogram. The performance of the nomograms was assessed with calibration plots and bootstrapped-concordance index and validated using validation cohorts. RESULTS: A total of 500 target LNs in 120 patients were successfully matched with node-by-node comparisons. A total of 353 LNs did not receive neoadjuvant therapy and 147 LNs received neoadjuvant chemoradiotherapy (neoCRT). Characterization of LNs not receiving neoadjuvant therapy and multivariate regression showed that the short diameter, preoperative CEA level, mrT-stage, border contour, and signal intensity were associated with a high risk of LN metastasis (P < 0.05). The nomogram predicted that the area under the curve was 0.855 (95% CI, 0.794-0.916) and 0.854 (95% CI, 0.727-0.980) in the training and validation cohorts, respectively. In the neoadjuvant therapy group, short diameter, ymrT-stage, internal signal, and MRI-EMVI were associated with LN positivity (P < 0.05), and the area under the curves using the nomogram was 0.912 (95% CI, 0.856-0.968) and 0.915 (95% CI, 0.817-1.000) in two cohorts. The calibration curves demonstrate good agreement between the predicted and actual probabilities for both the training and validation cohorts. CONCLUSION: Our nomograms combined with preoperative clinical and imaging biomarkers have the potential to improve the prediction of nodal involvement, which can be used as an essential reference for preoperative N staging and restaging of rectal cancer.

Focal unspecific bone uptake on [18F]-PSMA-1007 PET: a multicenter retrospective evaluation of the distribution, frequency, and quantitative parameters of a potential pitfall in prostate cancer imaging.

PURPOSE: Improved logistics and availability led to a rapid increase in the use of [18F]-PSMA-1007 for prostate cancer PET imaging. Initial data suggests increased uptake in benign lesions compared to [68 Ga]-PSMA-11, and clinical observations found increased unspecific bone uptake (UBU). We therefore investigate the frequency and characteristics of UBU in [18F]-PSMA-1007 PET. METHODS: We retrospectively analyzed [18F]-PSMA-1007 PET scans from four centers for the presence of UBU, defined as a focal mild-to-moderate uptake (SUVmax < 10.0) not obviously related to a benign or malignant cause. If present, up to three leading UBUs were quantified (SUVmax), localized, and correlated to clinical parameters, such as age, PSA, injected dose, Gleason score, tumor size (T1-T4), and type of PET scanner (analog vs. digital). Additionally, clinical and imaging follow-up results and therapeutic impact were evaluated. RESULTS: UBUs were identified in 179 out of 348 patients (51.4%). The most frequent localizations were ribs (57.5%) and pelvis (24.8%). The frequency of UBUs was not associated with PSA, Gleason score, tumor size, age, or the injected [18F]-PSMA-1007 dose. UBUs were significantly more frequent in images obtained with digital PET/CT scans (n = 74, 82%) than analog PET/CT scans (n = 221, 40.3%) (p = .0001) but not in digital PET/MR (n = 53, 51%) (p = .1599). In 80 out of 179 patients (44.7%), the interpretation of UBUs was critical for therapeutic management and therefore considered clinically relevant. For 65 UBUs, follow-ups were available: three biopsies, three radiotherapies with PSA follow-up, and 59 cases with imaging. After follow-up, UBUs were still considered unclear in 28 of 65 patients (43%), benign in 28 (43%), and malignant in nine (14%) patients. CONCLUSION: UBUs occur in two-thirds of patients imaged with [18F]-PSMA-1007 PET/CT and are significantly more frequent on digital PET scanners than analog scanners. UBUs should be interpreted carefully to avoid over-staging.

Endobronchial ultrasound-guided transbronchial needle aspiration in patients with previously treated lung cancer.

PURPOSE: The sampling and accurate diagnosis of lymph nodes during the clinical history of lung cancer are essential for selecting the appropriate treatment strategies. This study aims to evaluate the feasibility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) in patients with previously treated lung cancer. METHODS: Patients who underwent EBUS-TBNA after treatment for lung cancer were retrospectively reviewed. We classified the patients into two groups; Group 1 (G1): Indicated to have a recurrence of new lesions after radical surgery or chemo/radiotherapy with a curative intent; and Group 2 (G2): Indicated to have residual tumor cells after undergoing primary treatment for chemo/radiotherapy or re-staging after induction therapy prior to surgery. RESULTS: Seventy previously treated lung cancer cases (G1, n = 52; G2, n = 18) were enrolled. Thirty-two cases (61.5%) had recurrent disease in G1, and 9 cases (50.0%) had nodal metastasis in G2. The diagnostic accuracy was 95.2% in G1 and 88.9% in G2. Twenty-four cases were examined for epidermal growth factor receptor (EGFR) mutations, and 9 (37.5%) cases had mutations, including two cases with a T790M mutation. Furthermore, in one case, a re-biopsy revealed that the initial adenocarcinoma had transformed into small cell lung cancer. CONCLUSION: Performing EBUS-TBNA during lung cancer treatment showed a high diagnostic yield. Samples obtained by EBUS-TBNA were helpful in determining when to perform repeat biomarker testing as well as for making pathological re-evaluations.

[18F]Fluciclovine PET/CT: joint EANM and SNMMI procedure guideline for prostate cancer imaging-version 1.0.

The aim of this guideline is to provide standards for the recommendation, performance, interpretation, and reporting of [18F]Fluciclovine PET/CT for prostate cancer imaging. These recommendations will help to improve accuracy, precision, and repeatability of [18F]Fluciclovine PET/CT for prostate cancer essentially needed for implementation of this modality in science and routine clinical practice.

Comparison between laparoscopy and laparotomy in the surgical re-staging of granulosa cell tumors of the ovary.

OBJECTIVE: To evaluate the role of laparoscopic (LPS) and laparotomic (LPT) re-staging in patients with incompletely surgically staged ovarian granulosa cell tumors (OGCT). METHODS: We conducted a medical chart retrospective analysis of all patients with sex cord stromal tumors (SCSTs) who were managed in our division between March 1994 and March 2017. After a complete review of surgical and pathological notes, patients with incomplete staging were restaged according to the FIGO guidelines. Statistical analysis was conducted using Statistical Package version 20.0 for Windows (SPSS, Inc., Chicago, Illinois). RESULTS: Out of a total of 170 patients SCSTs, 84 patients (49,5%) received primary surgery that included a hysterectomy; 86 patients (50,5%) underwent fertility-sparing surgery. Eighty-one patients (48%) with diagnosis of OGCT were incompletely surgically staged at another institution. We evaluated our results in terms of laparoscopic approach (56 patients) and open treatment (25 patients). Among the IA patient's group, 1 was upstaged to IIB stage and 2 to IIIB; among patients with IC stage, 1 was upstaged to IIA, 2 to IIB and 1 to IIIB stage. Adjuvant chemotherapy was given to the upstaged patients with final stage IIB-IIIC. No statistically significant difference between laparoscopy and open-surgery was detected in terms of upstaged patients after second surgery (p = 0,36). CONCLUSION: According to our series, laparoscopic restaging compared to the open approach seems to be a feasible and efficient technique to complete surgical staging in patients with GCTs incorrectly staged. Surgical restaging seems to upstage a considerable number of OGCT, mainly in the initial stage IC group of patients. However, the impact of restaging on final outcome and survival remains to be demonstrated.

Impact of time to second transurethral resection on oncological outcomes of patients with high-grade T1 bladder cancer treated with intravesical Bacillus Calmette-Guerin.

PURPOSE: To determine the impact of time to restaging transurethral resection (Re-TUR) on recurrence-free survival (RFS), progression-free survival (PFS), and cancer specific survival (CSS) of patients with high-grade T1 bladder cancer (BC) treated with intravesical Bacillus Calmette-Guerin (BCG). MATERIALS AND PATIENTS: Our prospectively maintained NMIBC databases were queried to identify patients with high-grade T1 BC who underwent Re-TUR before receiving intravesical BCG treatment (induction + 1-year maintenance). Patients were divided into three groups based on time to Re-TUR (group A: ≤ 6 weeks; group B: > 6-12 weeks; group C: > 12-18 weeks). Kaplan-Meier plots were used to estimate differences in RFS, PFS, and CSS. Multivariate Cox regression analysis was used to assess the impact of time to Re-TUR on oncological outcomes. RESULTS: Overall, 269 high-grade T1 BC patients were eligible for the analysis. Nineteen (7.1%) had concomitant CIS. Median follow-up was 49.3 (IQR 25-65) months. Kaplan-Meier plots showed no differences in RFS, PFS, and CSS between the three groups. Multivariate Cox regression analysis showed that Group B had a slightly better RFS, while the other outcomes were not affected by time to Re-TUR. CONCLUSIONS: This is the first study testing the role of time to Re-TUR in a homogeneous population of patients with high-grade T1 BC who received complete BCG treatment. The study challenged the concept the sooner the Re-TUR the better, since time to Re-TUR did not significantly affect oncological outcomes.

FDG PET Hybrid Imaging.

Molecular imaging with positron emission tomography (PET) using tumour-seeking radiopharmaceuticals has gained wide acceptance in oncology with many clinical applications. The hybrid imaging modality PET/CT (computed tomography) allows assessing molecular as well as morphologic information at the same time. Therefore, PET/CT represents an efficient tool for whole-body staging and re-staging within one imaging modality. In oncology, the glucose analogue 18-F-fluorodeoxyglucose (FDG) is the most widely used PET/CT radiopharmaceutical in clinical routine. FDG PET and FDG PET/CT have been used for staging and re-staging of tumour patients in numerous studies. This chapter will discuss the use and the main indications of FDG PET/CT in oncology with special emphasis on lung cancer, lymphoma, head and neck cancer, melanoma and breast cancer (among other tumour entities). A review of the current literature is given with respect to primary diagnosis, staging and diagnosis of recurrent disease. Besides its integral role in diagnosis, staging and re-staging of disease in oncology, there is increasing evidence that FDG PET/CT can be used for therapy response assessment (possibly influencing therapeutic management and treatment planning) by evaluating tumour control, which will also be discussed in this chapter.

Limited Role for Routine Restaging After Neoadjuvant Therapy in Locally Advanced Rectal Cancer.

BACKGROUND: Although many patients with locally advanced rectal cancer undergo restaging imaging after neoadjuvant chemoradiotherapy and before surgery, the benefit of this practice is unclear. The purpose of this study was to examine the impact of reimaging on outcomes. MATERIALS AND METHODS: We performed a retrospective analysis of consecutive patients with stage 2 and 3 rectal adenocarcinoma treated with neoadjuvant chemoradiotherapy between May 2005 and April 2018. Patient and disease characteristics, imaging, treatment, and oncologic outcomes were compared between those who underwent restaging and those who went directly to surgery. Predictors of outcomes and cost effectiveness of restaging were determined. RESULTS: Of 224 patients, 146 underwent restaging. Six restaged patients had findings leading to a change in management. There was no difference in freedom from recurrence (P = 0.807) and overall survival (P = 0.684) based on restaging. Pretreatment carcinoembryonic antigen level >3 ng/mL (P = 0.010), clinical T stage 4 (P = 0.016), and pathologic T4 (P = 0.047) and N2 (P = 0.002) disease increased the risk of death, whereas adjuvant chemotherapy decreased the risk of death (P < 0.001) on multivariate analysis. Disease recurrence was lower with pelvic exenteration (P = 0.005) and in females (P = 0.039) and higher with pathologic N2 (P = 0.003) and N3 (P = 0.002) disease. The average cost of reimaging is $40,309 per change in management; however, $45 is saved per patient when downstream surgical costs are considered. CONCLUSIONS: Imaging restaging after neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer rarely changes treatment and does not improve survival. In a subset of patients at higher risk for worse outcome, reimaging may be beneficial.

Restaging [18F] fludeoxyglucose positron emission tomography/computed tomography scan in recurrent cutaneous squamous cell carcinoma: Diagnostic performance and prognostic significance.

BACKGROUND: There are no specific recommendations for [18F] fludeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) in assessing recurrent cutaneous squamous cell carcinoma (cSCC). OBJECTIVE: To evaluate FDG-PET/CT in recurrent cSCC. METHODS: FDG-PET/CT scans were retrospectively reviewed. Sites of abnormal uptake were noted and correlated with biopsy/histopathology studies, where available, and with follow-up imaging or clinical data in others. Comparison with available CT/magnetic resonance imaging was performed. The prognostic significance of PET/CT parameters was evaluated, and PET/CT-based change in management was recorded. RESULTS: A total of 115 FDG-PET/CT scans were analyzed in 100 consecutive patients with cSCC. Of these, 96 (84%) scans were positive for recurrence, and 25 showed distant metastases. PET/CT detected unsuspected disease sites in 39 of 115 scans (34%), locoregional disease in 14, distant metastases in 11, both locoregional disease and distant metastases in 8, additional local cutaneous disease in 5, and second malignancy in 1. Comparison of 78 PET/CT scans with available CT/magnetic resonance imaging showed 37 additional abnormalities on 23 PET/CT scans, predominantly including skin/subcutaneous lesions and nodes. PET/CT led to change in management in 28% of patients. On univariate/multivariate analysis, increased number of FDG-positive lesions and lung metastases on PET/CT was associated with increased risk of death/disease progression. LIMITATIONS: Retrospective study. CONCLUSIONS: FDG-PET/CT was sensitive in detecting recurrent disease in cSCC, led to change in management for 28% of patients, and proved to be of prognostic value.

68Ga-PSMA-11 PET-CT study in prostate cancer patients with biochemical recurrence and non-contributive 18F-Choline PET-CT: Impact on therapeutic decision-making and biomarker changes.

BACKGROUND: In this retrospective study, we investigated the impact of 68 Ga-PSMA-11 PET-CT (PSMA PET-CT) upon the treatment plan and therapeutic response obtained for Prostate Cancer (PCa) patients presenting an occult biochemical recurrence. METHODS: Forty-two patients with previously negative or doubtful 18F-Choline (FCH) were enrolled. PET images were recorded 1 h after injection of tracer. Only a few months after treatment ended, a PSA assay was requested to evaluate the therapeutic efficacy of the treatment based on PSMA results. RESULTS: PSMA-positive lesions were detected in 34/42 (80.9%) patients. Detection rates were 85.7% and 89.3% for serum PSA levels lower than 2 ng/mL, and >2 ng/mL, respectively. One hundred seventy-three lesions were detected: 132/173 in lymph nodes (76.3%), 22/173 as metastatic sites (bone or lung) (12.7%), and 19/173 in the prostate bed (10.9%). As a result of the PSMA PET-CT, therapeutic management changed in 31/42 patients (73.8%). With a follow-up of 4.9 ± 2.27 months, 32/42 (76.2%) PSA assays after treatment guided by PSMA PET-CT were collected. For 37.5% (12/32) of patients, the serum PSA level was lower than 0.2 ng/mL and a PSA decrease of over 50% in 8 (25.0%) other patients were obtained. CONCLUSION: Performing a PSMA PET-CT when FCH PET-CT was doubtful or negative allows the recurrence localization in more 80% of patients and this had a major clinical impact, as it resulted in treatment change in more than 70% of patients as well as a significant decrease in PSA levels in more than 60% of them.

Clinical utility of 68Ga-DOTATOC positron emission tomography/computed tomography for recurrent renal cell carcinoma.

PURPOSE: Positron emission tomography (PET)/computed tomography (CT) with 68Ga-labelled 1,4,7,10-tetraazacyclododecane-N,N',N″,N″'-tetraacetic acid-D-Phe1-Tyr3-octreotide (DOTATOC) has been accepted as a diagnostic imaging tool especially for patients with neuroendocrine tumours. However, its clinical usefulness for restaging of renal cell carcinoma (RCC) has not been fully investigated. This retrospective study was performed to elucidate the clinical value of PET/CT using 68Ga-DOTATOC in patients with known or suspected recurrent RCC. METHODS: We analysed 25 consecutive patients who underwent DOTATOC-PET/CT scans after surgery for RCC (23 clear cell, 1 papillary, 1 unclassified). PET/CT findings were reviewed and the detection rate was calculated on a patient and lesion basis. The detectability was compared in patients who also underwent PET/CT scans with 18F-fluorodeoxyglucose (FDG). Histopathological findings or clinical follow-up were used as the reference standard. RESULTS: Based on the final diagnosis, 76 recurrent or metastatic lesions were confirmed in this population. Of these lesions, 66 lesions in 22 patients were positive by DOTATOC-PET/CT. The patient-based and lesion-based sensitivity was 88% (22/25) and 87% (66/76), respectively. Twelve patients underwent both DOTATOC-PET/CT and FDG-PET/CT. The lesion-based sensitivity of DOTATOC was 74% (20/27), while that of FDG was 59% (16/27). Eight lesions were identified only by DOTATOC, but four lesions from papillary RCC were detected only by FDG. CONCLUSION: Our data indicate that DOTATOC-PET/CT would be useful for detecting recurrent foci in patients with clear cell RCC. DOTATOC-PET/CT and FDG-PET/CT are considered to have complementary roles.

The use of 68Ga-PET/CT PSMA in the staging of primary and suspected recurrent renal cell carcinoma.

PURPOSE: The role of 68Ga-PSMA PET/CT in the staging of prostate cancer is well known. PSMA is also overexpressed in the neovasculature of other tumours including renal cell carcinoma (RCC), suggesting there may be a role for the use of 68Ga-PSMA PET/CT. Thus far, there has been limited literature documenting the use of 68Ga-PSMA PET/CT in the investigation and management decisions of RCC. METHODS: This was a retrospective case series of patients who received a 68Ga-PSMA PET/CT scan for staging or restaging of RCC between July 2016 and December 2018. Primary outcome measure was to identify whether 68Ga-PSMA PET/CT changed management compared to standard diagnostic CT imaging. Analysis was based on four categories: (1) identification of new disease, (2) refuting disease on CT imaging, (3) identification of synchronous primaries, and (4) concordance with CT imaging. RESULTS: 38 68Ga-PSMA PET/CT scans met inclusion criteria. Primary staging scans were performed in 16 patients, of which 75% showed avid primary lesions, with the majority of clear cell subtype. Management was changed in 43.8% of patients. CT agreed with 68Ga-PSMA PET/CT in 37.5% of cases. Restaging scans were performed in 22 patients. 40.9% of patients had management changed by results of 68Ga- PSMA PET/CT. CT agreed with 68Ga- PSMA PET/CT in 36.4% of cases. Management was predominantly changed due to the identification of new sites of suspected metastases, as well as the detection of synchronous primaries. CONCLUSIONS: 68Ga-PSMA PET/CT directly changed management in 42.1% of cases. Strongest detection rates occurred in those patients with clear cell RCC. The results of this study suggest there may be merit in the use of the modality in the staging of RCC. Further analysis, both with respect to histological confirmation, efficacy and cost-benefit, is required to determine whether there is a role for routine 68Ga-PSMA PET/CT imaging.

Role of Positron Emission Tomography Imaging in Metabolically Active Renal Cell Carcinoma.

PURPOSE OF REVIEW: The clinical role of fluorine-18 fluoro-2-deoxyglucose (FDG)-positron emission tomography (PET) in renal cell carcinoma (RCC) is still evolving. Use of FDG PET in RCC is currently not a standard investigation in the diagnosis and staging of RCC due to its renal excretion. This review focuses on the clinical role and current status of FDG PET and PET/CT in RCC. RECENT FINDINGS: Studies investigating the role of FDG PET in localized RCC were largely disappointing. Several studies have demonstrated that the use of hybrid imaging PET/CT is feasible in evaluating the extra-renal disease. A current review of the literature determines PET/CT to be a valuable tool both in treatment decision-making and monitoring and in predicting the survival in recurrent and metastatic RCC. PET/CT might be a viable option in the evaluation of RCC, especially recurrent and metastatic disease. PET/CT has also shown to play a role in predicting survival and monitoring therapy response.

Restaging the axilla after neo-adjuvant chemotherapy for breast cancer: Predictive factors for residual metastatic lymph node disease with negative imaging findings.

To evaluate predictive factors for residual metastatic axillary lymph node (ALN) disease in patients with negative imaging findings after neo-adjuvant chemotherapy (NAC) for breast cancer. From January 2011 to December 2015, 206 patients underwent imaging including ultrasonography, MRI, and PET/CT for restaging the axilla after NAC. Data collected included preoperative information regarding histologic grade, hormone receptor (HR) status, and human epidermal growth factor receptor 2 (HER2) status. Multivariate logistic regression analysis was performed to compare patients with and without residual metastatic ALN disease among patients who showed negative imaging findings after NAC. Of the 181 and 25 patients with initially node-positive and node-negative disease, 131 (72.4%) and 23 (92.0%), respectively, showed negative imaging findings after NAC. Among these 131 and 23 patients, 53 (40.5%) and two patients (8.7%), respectively, had residual metastatic ALN disease. Low to moderate tumor grade (odds ratio [OR] = 5.2, P = 0.009), positive HR status (OR = 6.6, P = 0.003), and negative HER2 status (OR = 2.6, P = 0.048) were associated with residual metastatic ALN disease. Low to moderate histologic grade, positive HR status, and negative HER2 status may serve as predictors of residual metastatic ALN disease in patients with negative imaging findings after NAC for breast cancer.