Detection Of Primary Tumor Research Articles

Phase II study of uPAR-PET/CT for staging of primary breast cancer in comparison with ultrasound and fine needle biopsies

Accurate initial staging of patients with breast cancer is essential for planning optimal treatment strategies. However, currently, no imaging modality is able to detect lymph node metastases preoperatively with sufficient reliability; therefore, the N status depends on the sentinel node procedure for ~ 70% of patients. In a prospective clinical trial of breast cancer patients, we compared head-to-head uPAR-PET/CT with current standard-of-care, ultrasound (US) and fine needle biopsy (FNB) as staging methods. Forty-nine patients (48 women and 1 man) with biopsy-proven early breast cancer underwent uPAR-PET/CT prior to surgery. All image data were analyzed by two separate teams, each consisting of a highly experienced certified specialist in nuclear medicine and a highly experienced certified specialist in radiology for visualization of primary tumor lesions and detection of lymph node and distant metastases. Histopathological assessment and verification of malignancy in the excised tissues (primary tumors and lymph nodes) were considered standard-of-truth. On a per patient basis, uPAR PET/CT demonstrated a sensitivity of 94% [CI: 83–99%] for detecting the primary tumor (both teams). For the detection of axillary lymph nodes the pooled sensitivity of uPAR PET/CT was 33.3% [CI: 16.5–54.0%], specificity 87.0% [CI: 66.4–97.2%] and accuracy 58.0% [CI: 43.2–71.8%]. In comparison, the standard-of-care preoperative clinical staging algorithm with US and FNB had a sensitivity of 41% [CI: 22–61%] and specificity of 100% [CI: 85–100%] for axillary lymph node metastases. We conclude that the results do not support the use of uPAR PET/CT for staging in breast cancer patients. However, the finding that 94% of primary tumors were uPAR-PET positive may be encouraging for pursuing uPAR theranostics in localized disease. Additionally, other potential applications, such as using uPAR-PET as a prognostic imaging biomarker of tumor aggressiveness, remain to be investigated.

Semantic Segmentation of the Prostate Based on Onefold and Joint Multimodal Medical Images Using YOLOv4 and U-Net

Magnetic Resonance Imaging is increasing in importance in prostate cancer diagnosis due to the high accuracy and quality of the examination procedure. However, this process requires a time-consuming analysis of the results. Currently, machine vision is widely used in many areas. It enables automation and support in radiological studies. Successful detection of primary prostate tumors depends on the effective segmentation of the prostate itself. At times, a CT scan may be performed; alternatively, MRI may be the selected option. The data always reach a bottleneck stage. This paper presents the effective training of deep learning models to segment the prostate based on onefold and multimodal medical images. This approach supports the computer-aided diagnosis (CAD) system for radiologists as the first step in cancer exams. A comparison of two approaches designed for prostate segmentation is described. The first combines YOLOv4, the object detection neural network, and U-Net for a semantic segmentation based on onefold modality MRI images. The second presents the same method trained on multimodal images—a CT and MRI mixed dataset. The learning process was carried out in a cloud environment using GPU cards. The experiments are based on data from 120 patients who have undergone MRI and CT examinations. Several metrics evaluated the trained models. In the prostate semantic segmentation process, better results were achieved by mixed MRI with CT datasets. The best model achieved the value of 0.9685 for the Sørensen–Dice coefficient for the threshold value of 0.6.

A case report of late detection of primary mediastinum herm cell tumor

Germ cell tumors are rare malignant neoplasms. Extragondal localization accounts for about 10% of all germ cell tumors, with up to 3% being mediastinal. The low incidence, along with a nonspecific clinical presentation, complicates initial diagnosis and leads to delays in diagnosis and the initiation of specific treatment. Primary care plays a crucial role in detecting such tumors and in patient routing. At the outpatient stage, the patient should be examined and referred to a specialized facility for specific treatment as quickly as possible. For differential diagnosis at the initial stages between mediastinal germ cell tumors and lymphoproliferative diseases, mediastinal sarcomas, thymomas, and others, monitoring tumor markers is necessary: alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (beta-HCG), and lactate dehydrogenase (LDH). When these markers are elevated and time is critical, it is permissible to start specialized antitumor treatment without histological confirmation.Currently, it is also important to consider the role of the new coronavirus infection, which complicates differential diagnosis at the initial stages. This article presents a clinical case of late detection of a germ cell tumor and attempts to conduct systemic therapy in the context of the disease’s complicated progression.

6485 Unilateral Adrenal Metastasis From Unknown Primary Carcinoma Mimicking Primary Adrenocortical Carcinoma

Abstract Disclosure: S. Watanabe: None. S. Suzuki: None. K. Ishiwata: None. Y. Yamazaki: None. H. Sasano: None. K. Yokote: None. Background: Adrenal metastasis from carcinomas of the lung, breast, and melanoma are observed. However, isolated adrenal metastasis with unknown primary carcinoma origin has been rare, and the diagnosis is challenging. We encountered a case of unilateral adrenal tumor clinically diagnosed as non-functional primary adrenocortical carcinoma, but found to be a metastatic tumor on postoperative pathology. Clinical Case: A 68-year-old man was referred to our hospital for examination of an 8mm right adrenal incidentaloma. He underwent hormone therapy for prostate cancer four years ago, and the condition is in remission with no recurrence signs. Follow-up CT revealed that the adrenal tumor rapidly enlarged from 8 mm to 36 mm within six months, and its mean attenuation value was 38 HU. MRI showed that the adrenal tumor had a low signal intensity on T1 and a high signal on T2. At the same time, there is mediastinal lymphadenopathy and a 9-mm nodule in the lower lobe of the right lung, which was considered benign from the stable condition. FDG-PET/CT showed FDG uptake only in the right adrenal tumor (maximum standardized uptake value of 21.39). [1]23I-MIBG scintigraphy did not show any accumulations. The serum and urinary adrenal hormones were all within normal limits. Notably, tumor markers such as prostate-specific antigen (PSA), carcinoembryonic antigen (CEA), α-fetoprotein (AFP), and cancer antigen 19-9 (CA 19-9) were all within normal ranges. Therefore, we clinically suspected non-functional primary adrenocortical carcinoma, and the laparoscopic right adrenalectomy was performed. The resected right adrenal lesion was encapsulated and measured 79×54×22 mm. On histological analysis, the nodule comprised tumor cells with eosinophilic cytoplasm, and abundant tissue infiltrating lymphocytes. Immunohistochemical studies revealed that the tumor was not of adrenal origin due to negative steroidogenic factor-1 (SF-1) and inhibin alpha staining. From these results, the adrenal tumor was diagnosed as adrenal metastasis from unknown primary carcinoma. The tumor cells were positive for cytokeratin19, CEA, and thyroid transcription factor-1 but negative for PSA, p63, cytokeratin 5/6, insulinoma-associated protein-1, and synaptophysin. Genetically, the adrenal tumor harbored genomic abnormalities in CDKN2A, TP53, NF1, PBRM1, and KEAP1 genes. Conclusion: Isolated adrenal metastasis without a detectable primary tumor is rare but should be considered a differential diagnosis in the case of an enlarged, non-functioning adrenal tumor. Adrenalectomy or tumor biopsy may be actively considered to diagnose and determine the optimal course of treatment. Presentation: 6/3/2024

Head-to-Head Comparison of the Diagnostic Performance of FDG PET/CT and FDG PET/MRI in Patients With Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND. The available evidence on the use of FDG PET/MRI performed using an integrated system in patients with cancer has grown substantially. OBJECTIVE. The purpose of this study was to perform a systematic review and meta-analysis comparing the diagnostic performance of FDG PET/CT and FDG PET/MRI in patients with cancer. EVIDENCE ACQUISITION. MEDLINE, Embase, and the Cochrane Database of Systematic Reviews were searched for studies reporting a head-to-head comparison of the diagnostic performance of FDG PET/CT and FDG PET/MRI in patients with cancer from July 1, 2015, to January 25, 2023. The two modalities' diagnostic performance was summarized, stratified by performance end point. For end points with sufficient data, a meta-analysis was performed using bivariate modeling to produce summary estimates of pooled sensitivity and specificity. For the remaining end points, reported performance in individual studies was recorded. EVIDENCE SYNTHESIS. The systematic review included 29 studies with a total of 1656 patients. For patient-level detection of regional nodal metastases (five studies), pooled sensitivity and specificity for PET/MRI were 88% (95% CI, 74-95%) and 92% (95% CI, 71-98%), respectively, and for PET/CT were 86% (95% CI, 70-94%) and 86% (95% CI, 68-95%). For lesion-level detection of recurrence and/or metastases (five studies), pooled sensitivity and specificity for PET/MRI were 94% (95% CI, 78-99%) and 83% (95% CI, 76-88%), respectively, and for PET/CT were 91% (95% CI, 77-96%) and 81% (95% CI, 72-88%). In individual studies not included in the meta-analysis, PET/MRI in comparison with PET/CT showed staging accuracy in breast cancer of 98.0% versus 74.5% and in colorectal cancer of 96.2% versus 69.2%; sensitivity for primary tumor detection in cervical cancer of 93.2% versus 66.2%; and sensitivity, specificity, and accuracy for lesion-level liver metastasis detection of 91.1-98.0% versus 42.3-71.1%, 100.0% versus 83.3-98.6%, and 96.5-98.2% versus 44.7-86.7%, respectively. In three studies, management was more commonly impacted by information from PET/MRI (5.2-11.1%) than PET/CT (0.0-2.6%). CONCLUSION. PET/MRI showed comparable or superior diagnostic performance versus PET/CT across a range of cancers and end points. CLINICAL IMPACT. The findings help to identify clinical settings where PET/MRI may provide clinical benefit for oncologic evaluation. TRIAL REGISTRATION. Prospective Register of Systematic Reviews CRD42023433857.

Detection rate of gastrin-releasing peptide receptor (GRPr) targeted tracers for positron emission tomography (PET) imaging in primary prostate cancer: a systematic review and meta-analysis.

The gastrin-releasing peptide receptor (GRPr) has gained recognition as a promising target for both diagnostic and therapeutic applications in a variety of human cancers. This study aims to explore the primary tumor detection capabilities of [68Ga] Ga-GRPr PET imaging, specifically in newly diagnosed intra-prostatic prostate cancer lesions (PCa). Following PRISMA-DTA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy Studies) guidelines, a systematic literature search was conducted using the Medline, Embase, Scopus, and Web of Science databases. Data regarding patient characteristics and imaging procedure details-including the type of radiotracer used, administered activity, image acquisition time, scanner modality, criteria, and detection rate of index test-were extracted from the included studies. The pooled patient-and lesion-based detection rates, along with their corresponding 95% confidence intervals (CI), were calculated using a random effects model. The final analysis included 9 studies involving 291 patients and 350 intra-prostatic lesions with [68Ga] Ga-GRPr PET imaging in primary PCa. In per-patient-based analysis of [68Ga] Ga-GRPr PET imaging, the pooled detection rates of overall and patients with Gleason score ≥ 7 were 87.09% (95% CI 74.98-93.82) and 89.01% (95% CI 68.17-96.84), respectively. In per-lesion-based analysis, the pooled detection rate [68Ga] Ga-GRPr PET imaging was 78.54% (95% CI 69.8-85.29). The pooled detection rate mpMRI (multiparametric magnetic resonance imaging) in patient-based analysis was 91.85% (95% CI 80.12-96.92). The difference between the detection rates of the mpMRI and [68Ga] Ga-GRPr PET imaging was not statistically significant (OR 0.90, 95% CI 0.23-3.51). Our findings suggest that [68Ga] Ga-GRPr PET imaging has the potential as a diagnostic target for primary PCa. Future research is needed to determine the effectiveness of [68Ga] Ga-GRPr PET in delivering additional imaging data and guiding therapeutic decisions.

Analysis of PIK3CA mutations in the primary and recurrent tumors of hormone receptor positive/human epidermal growth factor receptor 2 negative breast cancer.

Our aim was to compare the PIK3CA mutation status in matched primary and recurrent tumors of hormone receptor positive/human epidermal growth factor receptor 2 negative (HR+/HER2-) breast cancer (BC) to gain insight into the optimization of patient selection and detection time for PIK3CA-targeted therapy. The data were from 3035 patients with BC diagnosed at the Breast Disease Center, Peking University First Hospital, between January 2008 and December 2017. Matched primary and recurrent samples were profiled using amplification-refractory mutation system-polymerase chain reaction covering 11 mutational hotspots in PIK3CA. PIK3CA mutations were detected in 54.3% primary tumors and 48.6% corresponding recurrences. PIK3CA mutation was detected in 37.5% cases in the locoregional recurrent group and 40.0% of distant metastasis, without a statistical difference. Besides, PIK3CA mutations were concordant in 88.6% of the matched pairs. For patients treated with neoadjuvant chemotherapy, 100% concordance was observed. However, PIK3CA mutation was neither correlated with clinicopathological features nor associated with clinical outcomes. Mutations in PIK3CA in HR+/HER2- BC generally progressed to recurrent tumors. The high concordance rate of PIK3CA mutation status between primary tumors and corresponding recurrences suggests that the detection of primary tumors could be a substitute approach when recurrent samples are not easily obtainable.

ASO Visual Abstract: Primary Tumour Detection in Carcinoma of Unknown Primary with Transoral Robotic Surgery (TORS) Tongue Base Mucosectomy-A Meta-analysis.

ASO Visual Abstract: Primary Tumour Detection in Carcinoma of Unknown Primary with Transoral Robotic Surgery (TORS) Tongue Base Mucosectomy-A Meta-analysis.

Deep learning-based detection of primary bone tumors around the knee joint on radiographs: a multicenter study.

Most primary bone tumors are often found in the bone around the knee joint. However, the detection of primary bone tumors on radiographs can be challenging for the inexperienced or junior radiologist. This study aimed to develop a deep learning (DL) model for the detection of primary bone tumors around the knee joint on radiographs. From four tertiary referral centers, we recruited 687 patients diagnosed with bone tumors (including osteosarcoma, chondrosarcoma, giant cell tumor of bone, bone cyst, enchondroma, fibrous dysplasia, etc.; 417 males, 270 females; mean age 22.8±13.2 years) by postoperative pathology or clinical imaging/follow-up, and 1,988 participants with normal bone radiographs (1,152 males, 836 females; mean age 27.9±12.2 years). The dataset was split into a training set for model development, an internal independent and an external test set for model validation. The trained model located bone tumor lesions and then detected tumor patients. Receiver operating characteristic curves and Cohen's kappa coefficient were used for evaluating detection performance. We compared the model's detection performance with that of two junior radiologists in the internal test set using permutation tests. The DL model correctly localized 94.5% and 92.9% bone tumors on radiographs in the internal and external test set, respectively. An accuracy of 0.964/0.920, and an area under the receiver operating characteristic curve (AUC) of 0.981/0.990 in DL detection of bone tumor patients were for the internal and external test set, respectively. Cohen's kappa coefficient of the model in the internal test set was significantly higher than that of the two junior radiologists with 4 and 3 years of experience in musculoskeletal radiology (Model vs. Reader A, 0.927 vs. 0.777, P<0.001; Model vs. Reader B, 0.927 vs. 0.841, P=0.033). The DL model achieved good performance in detecting primary bone tumors around the knee joint. This model had better performance than those of junior radiologists, indicating the potential for the detection of bone tumors on radiographs.

Biopsy of the facial nerve in slow-onset facial palsy

IntroductionPrimary squamous cell carcinoma of the parotid gland typically presents as a palpable, often painless mass. Peripheral facial palsy as the only sign of malignant neoplasia is rare. In these cases, the diagnosis is regularly confirmed by radiological imaging followed by surgical exploration and biopsy. However, if there is no detection of malignant lesions and no evidence of a tumor, the reluctance to take a biopsy of an unremarkable nerve can lead to misdiagnoses.Case reportA 40-year-old female patient without medical history presented to our clinic with a complete right-sided peripheral facial palsy that had slowly progressed for 2.5 years. All other otorhinolaryngological examination findings were within normal limits. Magnetic resonance imaging examination of the head and neck and 18-fluorodeoxyglucose positron emission tomography showed unremarkable results. We proceeded with surgical exploration, which revealed no evidence of a tumor and an externally completely unremarkable facial nerve. A biopsy from the main trunk area of the nerve revealed an infiltration by a squamous cell carcinoma. Total parotidectomy with resection and reconstruction of the facial nerve and neck dissection was performed. Considering the absence of a primary tumor and other tumor formations the diagnosis of a completely regressive primary squamous cell carcinoma of the parotid gland was confirmed.ConclusionIn conclusion, in the case of slow-onset peripheral facial palsy that persists without signs of recovery, a gadolinium-enhanced MRI should be performed. If imaging is unremarkable and there is no primary tumor detection along the course of the facial nerve, a surgical exploration with biopsy of the facial nerve is necessary.

Primary Tumour Detection in Carcinoma of Unknown Primary with Transoral Robotic Surgery (TORS) Tongue Base Mucosectomy: A Meta-analysis.

Head and neck carcinoma of unknown primary (CUP) represents a challenging diagnostic process when standard work-up fails to identify the primary tumour site. The aim of this systematic review and meta-analysis was to evaluate the diagnostic utility and complication profile of transoral robotic surgery (TORS) tongue base mucosectomy (TBM) in the management of CUP. An electronic database search was performed in the EMBASE, MEDLINE, PubMed and Cochrane databases. A meta-analysis of proportions was performed to obtain an estimate of the overall proportion for the detection and complication rates. Nine studies representing 235 patients with CUP who had TORS TBM were included in the final analysis. The overall pooled tumour detection rate was 66.2% [95% confidence interval (CI) 56.1-75.8]. The incidence of tumour detection in human papilloma virus (HPV)-positive cases (81.5%, 95% CI 60.8-96.4) was significantly higher than HPV-negative cases (2.3%, 95% CI 0.00-45.7). Weighted overall complication rate was 11.4% (95% CI 7.2-16.2). The majority were grade I or II (80%) according to the Clavien-Dindo classification. This meta-analysis suggests TORS to be safe and effective in localising the primary tumour site in patients with CUP. While the current data supports the use of TORS in patients who are HPV positive, larger numbers of HPV-negative cases are required to determine the true diagnostic effect with TORS before any valid conclusions can be inferred in this particular subgroup. Further research should focus on high quality prospective trials with stringent methodological work-up to minimise heterogeneity and allow for more accurate statistical analysis.

TMVP1448, a novel peptide improves detection of primary tumors and metastases by specifically targeting VEGFR-3

Lymphangiogenesis at primary tumor and draining lymph nodes plays a pivotal role in tumor metastasis, which has been demonstrated to be regulated by the vascular endothelial growth factor receptor 3 (VEGFR-3) pathway. However, the effect of molecular imaging peptides, which specifically bind VEGFR-3, in tracing tumors remains unclear. We prepared a novel peptide, TMVP1448, with high-affinity to VEGFR-3. The dissociation constant (KD) of TMVP1448 with VEGFR-3 was 7.07 ×10‐7 M. In vitro cellular assay showed that TMVP1448 could bind specifically with VEGFR-3. Near infrared imaging results showed that Cy7-TMVP1448 was able to accurately trace primary and metastatic cancers, and PET/CT results showed that [68Ga]Ga-DOTA-TMVP1448 was superior to commonly used radiotracers 18F-FDG. Additionally, no significant negative effect of TMVP1448 was found in mice. Our results suggested that TMVP1448 had great potential for future clinical applications in fluorescence imaging and nuclear imaging of tumors.

Role of FDG PET /CT In Detection of Primary Tumors in Patients with Bone Metastasis of Unknown Origin

Role of FDG PET /CT In Detection of Primary Tumors in Patients with Bone Metastasis of Unknown Origin

The role of machine learning in detecting primary brain tumors in Saudi pediatric patients through MRI images

Background and aimBrain tumors are defined as the uncontrollable growth of cells. They are known as the leading cause of death among pediatric patients. Artificial Intelligence is considered as one of the techniques used to improve radiology departments. Magnetic Resonance Imaging (MRI) is a key tool in detecting brain tumors. Medical images can be challenging and time-consuming for radiologists, particularly in the case of pediatric patients where the tumors may be small and difficult to detect. This study aims to explore the role of AI and measure the accuracy of AI methods in detecting primary brain tumors in pediatric patients by using MRI images. MethodologyA retrospective and analytical study was conducted, MRI images of pediatric patients with primary brain tumors were acquired from the Picture Archives and Communication System (PACS) of the radiology department at King Abdullah Specialist Children Hospital (KASCH). This study continues a total of (6435) MR images, this dataset was divided and expressed in different subsets, 70% of the images were trained (4493 in total) for model accuracy evaluation, and the rest which is 30% (1942) were tested images contains three types of primary brain tumors, glioma, Primitive Neuro-Ectodermal Tumors and pituitary tumors. Moreover, this dataset also contains normal images. Image classification and detection have been done by using Machine Learning algorithms which are coded in Python programming language. ResultsAfter applying Machine Learning algorithms on MRI images, Artificial Neural Network method resulted in an accurate detection of pediatric primary brain tumors and matched the radiologist's report. ConclusionNew Artificial Intelligence techniques applied in the imaging department have increased the information obtained from images to improve the accuracy of diagnosis along with radiologist's reports which will aid in better management of the patient's condition.

Role of FDG PET /CT in Detection of Primary Tumors in Patients with Bone Metastasis of Unknown Origin

Role of FDG PET /CT in Detection of Primary Tumors in Patients with Bone Metastasis of Unknown Origin

Superiority of 18F-FAPI-42 PET/CT in the detection of primary tumor and management of appendiceal neoplasm to 18F-FDG PET/CT and CE-CT

BackgroundIn the present study, we investigated the value of 18F-fibroblast-activation protein inhibitor (FAPI) positron emission tomography/computed tomography (18F-FAPI-42 PET/CT) to preoperative evaluations of appendiceal neoplasms and management for patients.MethodsThis single-center retrospective clinical study, including 16 untreated and 6 treated patients, was performed from January 2022 to May 2023 at Southern Medical University Nanfang Hospital. Histopathologic examination and imaging follow-up served as the reference standard. 18F-FAPI-42 PET/CT was compared to 18F-fluorodeoxyglucose (18F-FDG) PET/CT and contrast-enhanced CT (CE-CT) in terms of maximal standardized uptake value (SUVmax), diagnostic efficacy and impact on treatment decisions.ResultsThe accurate detection of primary tumors and peritoneal metastases were improved from 28.6% (4/14) and 50% (8/16) for CE-CT, and 43.8% (7/16) and 85.0% (17/20) for 18F-FDG PET/CT, to 87.5% (14/16) and 100% (20/20) for 18F-FAPI-42 PET/CT. Compared to 18F-FDG PET/CT, 18F-FAPI-42 PET/CT detected more regions infiltrated by peritoneal metastases (108 vs. 43), thus produced a higher peritoneal cancer index (PCI) score (median PCI: 12 vs. 5, P < 0.01). 18F-FAPI-42 PET/CT changed the intended treatment plans in 35.7% (5/14) of patients compared to CE-CT and 25% (4/16) of patients compared to 18F-FDG PET/CT but did not improve the management of patients with recurrent tumors.ConclusionsThe present study revealed that 18F-FAPI-42 PET/CT can supplement CE-CT and 18F-FDG PET/CT to provide a more accurate detection of appendiceal neoplasms and improved treatment decision making for patients.

Comparison of 68 Ga-FAPI-04 PET/CT with 18 F-FDG PET/CT for diagnosis and staging of gastric and colorectal cancer.

The objective of this study is to evaluate the effectiveness of 68 Ga-FAPI-04 PET/computed tomography (CT) for the diagnosis of primary and metastatic gastric cancer and colorectal cancer lesions as compared with 18 F-FDG PET/CT. Fifty-nine patients who underwent both 18 F-FDG and 68 Ga-FAPI-04 for initial staging or restaging were enrolled. Histopathological findings and clinical imaging follow-up were used as the reference standard. The diagnostic performance and TNM staging of the two tracers were calculated and compared. The maximum standardized uptake value (SUV max ), tumour-to-mediastinal blood pool ratio (TBR) (lesions SUV max /ascending aorta SUV mean ), and tumour-to-normal liver parenchyma ratio (TLR) (lesions SUV max /liver SUV mean ) of primary and metastatic lesions between two imaging modalities were measured and compared using the Wilcoxon signed-rank test and paired t -test. The two imaging agents are comparable for the detection of primary tumors. The sensitivity of 68 Ga-FAPI-04 PET/CT was higher than that of 18 F-FDG PET/CT for detecting lymph node metastases, peritoneal metastases, liver metastases, and bone metastases. In the patient-based analysis, the TLR for all lesions was significantly higher with 68 Ga-FAPI-04 PET/CT than with 18 F-FDG PET/CT (all P < 0.05). The accuracy (92.2 vs. 70.3%, P = 0.002) and sensitivity of 68 Ga-FAPI-04 were significantly higher than that of 18 F-FDG (78.6 vs. 71.4%, P = 0.011) in determining the lymph node status. 68 Ga-FAPI-04 has a higher accuracy in staging ( P = 0.041), which is mainly due to the ability of distant metastases detection. 68 Ga-FAPI-04 PET/CT may be superior in evaluating the diagnostic efficiency and staging accuracy of gastric and colorectal cancer.

European clinical practice guidelines for the definition, diagnosis, and treatment of oligometastatic esophagogastric cancer (OMEC-4)

IntroductionThe OligoMetastatic Esophagogastric Cancer (OMEC) project aims to provide clinical practice guidelines for the definition, diagnosis, and treatment of esophagogastric oligometastatic disease (OMD). MethodsGuidelines were developed according to AGREE II and GRADE principles. Guidelines were based on a systematic review (OMEC-1), clinical case discussions (OMEC-2), and a Delphi consensus study (OMEC-3) by 49 European expert centers for esophagogastric cancer. OMEC identified patients for whom the term OMD is considered or could be considered. Disease-free interval (DFI) was defined as the time between primary tumor treatment and detection of OMD. ResultsModerate to high quality of evidence was found (i.e. 1 randomized and 4 non-randomized phase II trials) resulting in moderate recommendations. OMD is considered in esophagogastric cancer patients with 1 organ with ≤ 3 metastases or 1 involved extra-regional lymph node station. In addition, OMD continues to be considered in patients with OMD without progression in number of metastases after systemic therapy. 18F-FDG PET/CT imaging is recommended for baseline staging and for restaging after systemic therapy when local treatment is considered. For patients with synchronous OMD or metachronous OMD and a DFI ≤ 2 years, recommended treatment consists of systemic therapy followed by restaging to assess suitability for local treatment. For patients with metachronous OMD and DFI > 2 years, upfront local treatment is additionally recommended. DiscussionThese multidisciplinary European clinical practice guidelines for the uniform definition, diagnosis and treatment of esophagogastric OMD can be used to standardize inclusion criteria in future clinical trials and to reduce variation in treatment.

Comparison of Ga-68 PSMA PET/CT and Multiparametric MRI for Initial Detection and Staging of Prostate Cancer

Abstract Background Multiparametric magnetic resonance imaging (mpMRI) is widely used for the evaluation of prostate cancer and is known to have better accuracy. Gallium-68 prostate-specific membrane antigen (Ga-68 PSMA) is a radiotracer that shows high localization in prostate cancer cells. Purpose The purpose of this study was to assess the sensitivity and utility of Ga-68 PSMA positron emission tomography/computed tomography (PET/CT) in comparison with mpMRI as a noninvasive imaging technique for the initial diagnosis and locoregional staging of prostate cancer using transrectal ultrasound (TRUS)-guided biopsy as gold standard. Materials and Methods This prospective observational study conducted from August 2017 to April 2020 evaluated 60 men (n = 60) with biopsy-proven prostate carcinoma. They underwent mpMRI and Ga-68 PSMA PET/CT scans within 14 days with TRUS biopsy being gold standard. T staging of disease, N staging of lymph nodes within the pelvis, and M staging of lesions in pelvic bones (within the imaging field of mpMRI) were compared using PSPP version 1.0.1 statistical software. Results All 60 men with a mean age of 69.9 ± 9.35 years showed Ga-68 PSMA avid disease, whereas 55 were detected by mpMRI. The sensitivity in detection of prostate lesions (with 95% confidence interval) was 99.08% for Ga-68 PSMA PET/CT and 84.40% for mpMRI. Ga-68 PSMA PET/CT detected greater number of patients with regional lymph nodal involvement (19/60) as compared with mpMRI (12/60). Ga-68 PSMA PET/CT showed PSMA avid pelvic skeletal lesions in nine patients, whereas mpMRI detected pelvic lesions in six patients. In addition, four other patients showed extrapelvic skeletal lesions on Ga-68 PSMA PET/CT. Conclusion Ga-68 PSMA PET/CT has superior sensitivity in detection of primary prostate tumor, as compared with mpMRI. Both modalities correlate well in detection of seminal vesicle involvement. Ga-68 PSMA PET/CT outperformed mpMRI in detection of lymph nodal and skeletal metastases. Hence, Ga-68 PSMA PET/CT should be considered as first-line diagnostic modality for carcinoma prostate. Summary Statement: Ga-68 PSMA PET/CT shows superior diagnostic performance than mpMRI in the evaluation of prostate cancer.

Design of a New 99mTc-radiolabeled Cyclo-peptide as Promising Molecular Imaging Agent of CXCR4 Receptor: Molecular Docking, Synthesis, Radiolabeling, and Biological Evaluation.

C-X-C Chemokine receptor type 4 (CXCR4) is often overexpressed or overactivated in different types and stages of cancer disease. Therefore, it is considered a promising target for imaging and early detection of primary tumors and metastasis. In the present research, a new cyclo-peptide radiolabelled with 99mTc, 99mTc-Cyclo [D-Phe-D-Tyr-Lys (HYNIC)- D-Arg-2-Nal-Gly-Lys(iPr)], was designed based on the parental LY251029 peptide, as a potential in vivo imaging agent of CXCR4-expressing tumors. The radioligand was successfully prepared using the method of Fmoc solid-phase peptide synthesis and was evaluated in biological assessment. Molecular docking findings revealed high affinity (binding energy of -9.7 kcal/mol) and effective interaction of Cyclo [D-Phe- D-Tyr-Lys (HYNIC)-D-Arg-2-Nal-Gly-Lys(iPr)] in the binding pocket of CXCR4 receptor (PDB code: 3OE0) as well. The synthesized peptide and its purity were assessed by both reversed-phase high-performance liquid chromatography (RP-HPLC) and mass spectroscopy. High stability (95%, n = 3) in human serum and favorable affinity (Kd = 28.70 ± 13.56 nM and Bmax = 1.896 ± 0.123 fmol/mg protein) in the B16-F10 cell line resulted. Biodistribution evaluation findings and planar image interpretation of mice both showed high affinity and selectivity of the radiotracer to the CXCR4 receptors. Therefore, the findings indicate this designed radioligand could be used as a potential SPECT imaging agent in highly proliferated CXCR4 receptor tumors.