Detection Of Pelvic Nodes Research Articles

FAOT-Net: A 1.5-Stage Framework for 3D Pelvic Lymph Node Detection With Online Candidate Tuning.

Accurate and automatic detection of pelvic lymph nodes in computed tomography (CT) scans is critical for diagnosing lymph node metastasis in colorectal cancer, which in turn plays a crucial role in its staging, treatment planning, surgical guidance, and postoperative follow-up of colorectal cancer. However, achieving high detection sensitivity and specificity poses a challenge due to the small and variable sizes of these nodes, as well as the presence of numerous similar signals within the complex pelvic CT image. To tackle these issues, we propose a 3D feature-aware online-tuning network (FAOT-Net) that introduces a novel 1.5-stage structure to seamlessly integrate detection and refinement via our online candidate tuning process and takes advantage of multi-level information through the tailored feature flow. Furthermore, we redesign the anchor fitting and anchor matching strategies to further improve detection performance in a nearly hyperparameter-free manner. Our framework achieves the FROC score of 52.8 and the sensitivity of 91.7% with 16 false positives per scan on the PLNDataset. Code will be available at: github.com/SCUsomebody/FAOT-Net/.

Hotspots and frontiers in PSMA research for prostate cancer: a bibliometric and visualization analysis over the past 20 years

BackgroundProstate-specific membrane antigen (PSMA)-targeted imaging and therapy have significantly changed the management of patients with prostate cancer (PCa) at different disease stages. This advancement has attracted the attention of scholars, leading to a prolific output of scholarly publications. This study comprehensively outlines the knowledge framework associated with PSMA-based diagnosis and treatment of PCa through the application of bibliometric analysis, and discusses the potential research trends and foci.MethodsArticles and reviews related to PSMA for prostate cancer from 2003 to 2022 were retrieved from Web of Science Core Collection. VOSviewer, Citespace, and R-bibliometrix were primarily employed to execute and visually represent co-authorship, co-citation, and co-occurrence analysis of countries, institutions, authors, references and keywords in this field.ResultsA total of 3830 papers were included. The papers on the field of PSMA-based PCa therapy and imaging had been continuously increased since 2003, but the rate has slowed from 2020. The United States made the largest contribution in this field, in terms of publications 997 (26.03%), H-index (110) and total citations (53,167 times). We identified the most productive institution were Technical University of Munich, and Australian institutions had become very active in recent years. Journal of Nuclear Medicine was the most prominent journal in this field. Professors Matthias Eiber and Martin G Pomper made great achievements, while Ali Afshar-Oromieh was the most co-cited author. According to the result of keywords and topics analysis, “ga-68 labeled psma ligand”, “radiation dosimetry” and “HBED-CC” were major research areas in the near future, while "Extended pelvic lymph node dissection" was considered to be the future research foci.ConclusionsThe field of psma-based PCa therapy and imaging is in the stage of vigorous development and has a bright prospect. The United States and Germany have achieved outstanding results in this area, while Australia has recently developed rapidly. It is foreseeable that more research foci will be lied in the early detection of pelvic lymph nodes and the multimodal imaging-guided surgery.

Different imaging techniques to detect pelvic lymph nodes affection in patients with gynecological cancers. A comparative study

Objectives: Pelvic lymph nodes affection is a common finding in patients with gynecological cancers and it has an important effect on prognosis and survival of the patients. The ultimate goal was to compare different radiological techniques used for detection of pelvic lymph nodes in patients with gynecological cancers, comparison between ultrasound, computerized tomography and magnetic resonance imaging in relation to operative and histopathological findings. Patients and Methods: The study included 300 patients with gynecological cancers treated surgically. Assessment of pelvic lymph nodes metastasis using ultrasound, CT, MRI and clinical intra-operative examinations. Correlations between the results of pelvic lymph nodes affection techniques and the final histopathological examination were done. Results: The study included 300 cases with operable gynecological cancers; 162 of them were with endometrial cancer, 129 of them were with ovarian cancer and 9 of them were with cervical cancer. Sensitivity of Ultrasound examination for malignant pelvic lymph nodes detection was 61.5 %, specificity of CT was 92.2%, accuracy of MRI was 63.3% and sensitivity, specificity and accuracy of clinical intra-operative assessment was 83%, 77% & 81 % respectively. Conclusion: Clinical intra-operative pelvic lymph nodes assessment is the most sensitive tool to detect pathologically enlarged lymph nodes in comparison to ultrasound, CT and MRI, while MRI is the most specific tool.

Optimization of follow-up MRI protocol for malignant neoplasms of the female pelvis

Introduction. MRI is widely used to follow-up malignant neoplasms of the female pelvis. Aim. To optimize the use of MRI sequences for follow-up of female patients with malignant pelvic neoplasms. Materials and methods. Retrospective analysis of female pelvic MRI has been performed on 1.5 T MR scanner. This study includes 530 protocols. Results. The authors describe different protocols for assessment and differential diagnosis of recurrence, postradiation and postoperative changes. It includes applicable sequences, axis and the structure which require evaluation. In all cases, dynamic follow-up has to include analysis of patient's previous studies, anamnesis, previous treatment, as well as the end of chemotherapy and radiotherapy. All of the above, combined with the oncologist's treatment of choice determines the objective of this study. Nowadays, MRI is the method which most accurately characterizes postoperative and postradiation structural changes. MRI is useful in detection of pelvic lymph nodes. The role of MRI has high potential in assessing the effectiveness of chemotherapy and radiation therapy. Conclusion. In order to make the optimal scan protocol, follow-up of malignant neoplasms of the pelvic organs in women require the use of clinical and anamnestic data along with the results of patient's previous studies. The combined use of various sequences and techniques can improve the diagnostic significance of pelvic MRI at follow-up. Contrast enhancement has additional role in diagnostics of recurrent of pelvic organs in women. The use of different contrast enhancement techniques has proven effective in case of postradiation and postoperative complications.

Current and Emerging Clinical Applications of PSMA PET Diagnostic Imaging for Prostate Cancer.

Prostate-specific membrane antigen (PSMA) is highly expressed on most prostate cancer (PCa) cells, and several PSMA ligands for PET imaging are now available worldwide. 68Ga-PSMA-11 has already received U.S. Food and Drug Administration and European Medicines Agency approval, and use of PSMA PET is currently suggested by several international guidelines for investigating PCa in different clinical settings. In primary PCa, PSMA PET has been shown to be superior to cross-sectional imaging for the detection of pelvic lymph nodes and distant metastases with subsequent clinical management changes. Additionally, it might also have a role in intraprostatic tumor localization, especially when combined with multiparametric MRI. In a setting of PCa recurrence, higher detection rates have been observed than for any other available imaging techniques, especially at low prostate-specific antigen values. Furthermore, PSMA PET consistently led to a shift in clinical management, thus increasing the proportion of radiotherapy, surgery, or other focal therapies at the expense of systemic options or no treatment. In oligometastatic disease after radical surgery, PSMA PET may be relevant in guiding a metastasis-directed therapy approach, as preliminary data seem to suggest a benefit in terms of progression-free survival after treatment of PSMA PET-positive lesions. As a staging and gatekeeping technique, PSMA PET represents a reliable whole-body imaging procedure in combination with second-line therapy of castration-resistant PCa, as well as being pivotal when assessing patients eligible for radioligand therapy such as 177Lu-PSMA. This critical review aims at providing a comprehensive overview of the latest literature on the current or emerging main indications, as well as a general outlook on the recommended interpretation criteria for PSMA PET imaging.

Diagnostic PET/CT for detecting malignant lymph nodes in patients with cervical cancer Stage IB1

Background: After initial diagnosis of cervical cancer, patients are staged and clinically evaluated with PET/CT in order to assess disease extent. Patients with Stage IB1 disease usually undergo definitive surgery. The present authors’ objective was to evaluate the diagnostic value of PET/CT in cervical cancer Stage IB1. Materials and Methods: By searching the Danish Gynecological Database (DGCD) the authors identified 144 patients treated for cervical cancer Stage IB1 from 2012-2015 at Rigshospitalet, University Hospital Copenhagen, Denmark. Patients who underwent a PET/CT scan and either definitive surgery or diagnostic laparoscopy were included for further analysis. Results: One hundred forty patients had a PET/CT scan and results were available for 136 patients, six of which had suspicious lymph nodes; three patients did not have metastases and three patients did. One hundred thirty patients did not have suspicious lymph nodes on PET/CT. Histological results were available for 106 of these patients and 97 of these did not have metastases and nine patients did. Out of all the 12 patients with metastatic lymph nodes, 11 had pelvic, none had para-aortic disease, and data regarding localization was missing for the last patient. Regarding PET/CT detection of pelvic lymph nodes, the sensitivity was 25%, specificity 97%, positive predictive value 50%, and negative predictive value 92%. Conclusion: The sensitivity and positive predictive value of PET/CT in cervical cancer Stage IB1 patients were low. PET/CT cannot replace surgical lymphadenectomy and histologic examination in these patients.

The Accuracy of Integrated [(18)F] Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Detection of Pelvic and Para-aortic Nodal Metastasis in Patients with High Risk Endometrial Cancer.

Lymph nodal (LN) metastasis is the most important prognostic factor in high-risk endometrial cancer. However, the benefit of routine lymphadenectomy in endometrial cancer is controversial. This study was conducted to assess the accuracy of [18F] fluorodeoxyglucose-positron emission tomography/computed tomography ([18F] FDG-PET/CT) in detection of pelvic and para-aortic nodal metastases in high-risk endometrial cancer. 20 patients with high-risk endometrial carcinoma underwent [18F] FDG-PET/CT followed by total abdominal hysterectomy, bilateral salpingo-oophorectomy and systematic pelvic lymphadenectomy with or without para-aortic lymphadenectomy. The findings on histopathology were compared with [18F] FDG-PET/CT findings to calculate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [18F] FDG-PET/CT. The pelvic nodal findings were analyzed on a patient and nodal chain based criteria. The para-aortic nodal findings were reported separately. Histopathology documented nodal involvement in two patients (10%). For detection of pelvic nodes, on a patient based analysis, [18F] FDG-PET/CT had a sensitivity of 100%, specificity of 61.11%, PPV of 22.22%, NPV of 100% and accuracy of 65% and on a nodal chain based analysis, [18F] FDG-PET/CT had a sensitivity of 100%, specificity of 80%, PPV of 20%, NPV of 100%, and accuracy of 80.95%. For detection of para-aortic nodes, [18F] FDG-PET/CT had sensitivity of 100%, specificity of 66.67%, PPV of 20%, NPV of 100%, and accuracy of 69.23%. Although [18F] FDG-PET/CT has high sensitivity for detection of LN metastasis in endometrial carcinoma, it had moderate accuracy and high false positivity. However, the high NPV is important in selecting patients in whom lymphadenectomy may be omitted.

Observer variation of magnetic resonance imaging and diffusion weighted imaging in pelvic lymph node detection

Aim Conventional MRI and the recently developed diffusion weighted imaging (DWI) technique both are being used for the detection of pelvic lymph node metastasis in gynaecologic cancers. Little is known about the reproducibility of DWI. This study assesses the reproducibility of pelvic lymph node detection by conventional MRI and DWI. Materials and methods 17 patients with gynaecological malignancies eligible for curative surgery were selected as population of interest. They had undergone preoperative conventional MRI and DWI on a 3.0 T MR scanner. All images were evaluated by two experienced radiologists. Inter- and intra-observer agreements were assessed, and whether lymph node size and region were related to reproducibility. Differences were tested by Chi-square statistics. Results The reproducibility ranged between 42% and 65% for the two observers and for the two imaging tests, conventional MRI and DWI. Higher percentages of agreement were found for larger lymph nodes, i.e. for long as well as short axis diameter exceeding 5 mm. Also, agreement was better for lymph nodes in the external iliac region and the obturator region compared to detection of lymph nodes in the common iliac area. Results for the newer technique, DWI, were comparable to the results of the more conventional MRI sequences. Conclusion Reproducibility of MRI and DWI in the detection of pelvic lymph nodes in patients with a gynaecological malignancy was similar. For lymph nodes exceeding 5 mm in both long and short axis diameter the agreement was considerably better than for smaller nodes.

Detection and Evaluation of Pelvic Lymph Nodes in Patients With Gynecologic Malignancies Using Body Diffusion-Weighted Magnetic Resonance Imaging

In this study, the potential in detecting and evaluating pelvic lymph node metastases on body diffusion-weighted (DW) images was evaluated in patients with gynecologic malignancies. This study included 18 patients with gynecologic malignancy who underwent magnetic resonance imaging in the pelvis using a 1.5-T superconductive magnet. The identification of pelvic nodes on only T2-weighted (T2W) axial images and on DW axial images in addition to T2W axial images was examined and compared. Moreover, we measured and calculated a short-axis diameter, a long-axis diameter, and a ratio of short- and long-axis diameter of nodes on the T2W images and the apparent diffusion coefficient (ADC) values of the nodes on the DW images. These results were compared with histopathologic results. First, 136 (40%) of 340 dissected nodes were identified on T2W images, and 249 (73%) of 340 dissected nodes were identified on DW images in addition to T2W images. Second, the differences in the short-axis diameter, the long-axis diameter, and the ratio of short- and long-axis diameter on T2W images between metastatic and nonmetastatic nodes were not significant. The differences in the ADC values between metastatic and nonmetastatic nodes were not significant. Body DW images are useful in detection of pelvic lymph nodes in patients with gynecologic malignancy. However, the measurement of ADC values does not contribute to a diagnosis of metastatic nodes.

Detection of pelvic lymph node micrometastasis in stage IA2–IB2 cervical cancer by immunohistochemical analysis

Objective. The objectives of this study were to (1) determine the incidence of lymph node micrometastasis in cervical cancer by immunohistochemical analysis and (2) determine if the presence of micrometastasis is a poor prognostic feature in early cervical cancer. Methods. We retrospectively reviewed the medical records of 62 patients who underwent radical hysterectomy and lymphadenectomy for FIGO stage IA2–IB2 cervical cancer at Stanford University Hospital from 1990 to 2000. Forty-nine patients with negative lymph nodes were identified. A total of 976 formalin-fixed paraffin-embedded pelvic lymphadenectomy specimens were serially sectioned and stained with anti-cytokeratin antibodies AE1 and AE1/CAM5.2. Results. Six patients had stage IA2 disease, 37 had stage IB1, and 6 had IB2. The mean age of the patients was 44 years (range, 24–76). Seventy-one percent had squamous cell carcinomas, 22% had adenocarcinomas, and 6% had other types. Lymph node micrometastases were immunohistochemically detected in 4 of the 49 (8.1%) patients, comprising 4 of 976 (0.41%) pelvic lymph nodes examined. Twelve of 45 (15.6%) patients with negative nodes had lymph-vascular space invasion (LVSI) whereas 3 of 4 (75%) patients with micrometastases had LVSI. At a mean follow-up time of 39.4 months, 2 of 4 (50%) patients with micrometastasis had recurrent disease, while 3 of 45 (6.7%) patients without micrometastasis developed recurrent disease. Conclusions. These preliminary data suggest that immunohistochemical detection of pelvic lymph nodes is more frequent in patients with LVSI and may identify patients needing adjuvant chemoradiation.