Detection Of New Lesions Research Articles

Diagnostic and therapeutic considerations in patients with bilateral diffuse uveal melanocytic proliferation.

This review aims to summarize the current knowledge concerning the clinical features, diagnostic work-up, and therapeutic approach of bilateral diffuse uveal melanocytic proliferation (BDUMP). A meticulous literature search was performed in the PubMed database. A supplementary search was made in Google Scholar to complete the collected items. Our search strategy utilized the following keywords: "bilateral diffuse uveal melanocytic proliferation", "BDUMP", and "Paraneoplastic Syndrome". Articles were considered based on their relevance, with the search spanning publications up to 2023. Studies were excluded if they did not contribute pertinent information or lacked methodological rigor. A critical appraisal of included studies was conducted, assessing study design, sample size, methodology, and potential bias, ensuring a thorough and transparent review process. BDUMP is a rare and potentially sight-threatening condition characterized by the bilateral proliferation of melanocytes within the uvea. BDUMP is typically observed in middle-aged or elderly individuals and is often associated with an underlying malignancy, most commonly of gastrointestinal origin. BDUMP is frequently misdiagnosed as a benign nevus or choroidal metastasis, leading to delayed diagnosis and treatment. The ophthalmic symptoms and signs typically precede the diagnosis of a systemic malignancy, emphasizing the crucial role of ophthalmologists in the recognition of BDUMP. Several diagnostic modalities can aid in the diagnosis of BDUMP, including ophthalmic examination, imaging studies such as optical coherence tomography, fluorescein angiography, and indocyanine green angiography, and biopsy of the uveal tissue. Treatment of BDUMP is directed towards the underlying malignancy and may include chemotherapy, radiotherapy, or surgical resection. Additionally, strict monitoring with regular follow-ups may contribute to the detection of new lesions and the reduction in the size of existing ones. BDUMP can be considered a potential biomarker in the management of malignancies, especially when the primary underlying tumor has not been detected. Further research is needed to better understand the pathogenesis of BDUMP and its association with malignancy.

Association between SPECT/CT total tumor volume (TTV) and new lesions (NLs) in early cycles of 177Lu-PSMA-617 (LuPSMA) and progression-free and overall survival (PFS and OS) in men with metastatic castration-resistant prostate cancer (mCRPC).

40 Background: LuPSMA is a newly established treatment in patients with mCRPC, but PSA and survival outcomes vary widely, and predictors of treatment responses are needed. LuPSMA delivers radiation to tumor tissues that can also be imaged with SPECT/CT which provides semiquantitative estimates of TTV and identification of NLs. This study investigates the use of SPECT/CT in early cycles to predict LuPSMA outcomes. Methods: Between June and December 2022, mCRPC patients who initiated the 2nd cycle of LuPSMA with SPECT/CT 24 hours post-treatment were retrospectively reviewed. We evaluated associations between TTV and the appearance of NLs at the start of the 2nd or 3rd cycle with PFS and OS using Cox regression analysis. NLs were classified as non-PSMA-avid with no or low uptake (< liver) with corresponding findings on CT and PSMA-avid (uptake > liver). All analyses were adjusted for change in PSA relative to baseline. Results: Sixty-six mCRPC patients (median age, 73.5) received a median of 4 (IQR: 3-5) cycles of LuPSMA. Median follow-up starting at 2nd cycle was 26 weeks (IQR: 21-36) with 47/66 (71%) alive at the time of the analysis. A reduction of ≥50% in PSA (PSA50) was noted in 33/66 (50%) patients. Changes in PSA and TTV at 2nd and 3rd cycle were apparently concordant in 50/66 (76%) and 42/51 (82%) and were significantly correlated (r= 0.55 and 0.56, both p<0.001). Patients with higher absolute TTV adjusted for PSA change at 2nd cycle had worse PFS and OS (HR=1.3 and 2.26) with consistent results at 3rd cycle (Table). NLs were detected in 13/66 (7/13 PSMA-avid, 6/13 non-PSMA-avid) and 7/51 patients (5/7 PSMA-avid, 2/7 non-PSMA-avid) at 2nd and 3rd cycle, respectively. Patients with NLs at 2nd cycle had higher risks of progression and death (HR=4.53 and 6.28). Conclusions: Higher SPECT/CT TTV at 2nd and 3rd cycle and detection of NLs at 2nd cycle were associated with higher risks of progression and death. Although changes in PSA and TTV were correlated, absolute SPECT/CT TTV in early cycles provided a complementary ability to predict outcomes of LuPSMA. [Table: see text]

Toward automating RECIST 1.1: Improving AI new lesion detection with longitudinal image data.

e13545 Background: Automating RECIST 1.1 would offer benefits in speed, consistency, and cost of clinical trial imaging reads. Detection of new lesions is subjective and a common source of reader adjudication. Current AI lesion detection typically uses single timepoint images. The use of temporal data in AI is a rapidly evolving field in non-medical applications and new lesion detection in response assessment may benefit from longitudinal multi timepoint images. We explore the impact of longitudinal image input to deep neural networks for new lesion detection; as a proof of concept, we compare single vs dual timepoint input in new liver lesion detection in CT. Methods: We utilized CT images from two public datasets: 1) diseased liver (DL), a subset of DeepLesion (doi: 10.1117/1.JMI.5.3.036501), and 2) healthy liver (HL) from potential liver donors (Med Image Anal 69 (2021) 101950).. Due to the lack of a publicly available longitudinal image dataset with new lesions, we simulated (“sim”) a longitudinal study by registering HL scans (sim healthy baseline) with DL scans (sim follow up with new lesion) and selecting well-paired images using mutual information. From each pair of scans, we select one positive (with new lesion on follow up) and one negative (without lesion on follow up) 6x6cm image patch from within the liver, creating a dataset of 3296 patches with a balanced number of pos/neg samples. We trained two deep neural networks to classify the presence of a new liver lesion: 1) a conventional single timepoint model (ST) trained on DL patches only, i.e. using the follow up scan only, and 2) an experimental dual-timepoint model (DT) trained on patch pairs from DL-HL paired scans. We used 5-fold cross validation and paired t tests to compare model AUC and accuracy. Results: Of 10,594 CT studies (4,427 patients, pts) in DeepLesion, we paired 1648 DL scans (946 pts with liver lesions) with one of 20 registered HL scans (20 pts). The DT model outperformed the ST model, increasing AUC from 0.914 ± 0.002 to 0.929 ± 0.005 (p=0.040), with similar trends in accuracy (dataset split, Table 1). Conclusions: The DT model outperformed the ST model in the detection of new liver lesions, suggesting preliminary the benefit of multi-timepoint input to a deep neural network using sim longitudinal data. The use of longitudinal image data to improve interval change detection is a step towards automating radiologic response assessment in clinical trials. We plan to extend this work to automate new lesion detection in real clinical trial longitudinal images. Results (bold) are reported on test set across 5 folds. N image patches (ST) or patch pairs (DT). [Table: see text]

Evaluation of the Statistical Detection of Change Algorithm for Screening Patients with MS with New Lesion Activity on Longitudinal Brain MRI.

Identification of new MS lesions on longitudinal MR imaging by human readers is time-consuming and prone to error. Our objective was to evaluate the improvement in the performance of subject-level detection by readers when assisted by the automated statistical detection of change algorithm. A total of 200 patients with MS with a mean interscan interval of 13.2 (SD, 2.4) months were included. Statistical detection of change was applied to the baseline and follow-up FLAIR images to detect potential new lesions for confirmation by readers (Reader + statistical detection of change method). This method was compared with readers operating in the clinical workflow (Reader method) for a subject-level detection of new lesions. Reader + statistical detection of change found 30 subjects (15.0%) with at least 1 new lesion, while Reader detected 16 subjects (8.0%). As a subject-level screening tool, statistical detection of change achieved a perfect sensitivity of 1.00 (95% CI, 0.88-1.00) and a moderate specificity of 0.67 (95% CI, 0.59-0.74). The agreement on a subject level was 0.91 (95% CI, 0.87-0.95) between Reader + statistical detection of change and Reader, and 0.72 (95% CI, 0.66-0.78) between Reader + statistical detection of change and statistical detection of change. The statistical detection of change algorithm can serve as a time-saving screening tool to assist human readers in verifying 3D FLAIR images of patients with MS with suspected new lesions. Our promising results warrant further evaluation of statistical detection of change in prospective multireader clinical studies.

Same-day comparative protocol PET/CT-PET/MRI [68 Ga]Ga-DOTA-TOC in paragangliomas and pheochromocytomas: an approach to personalized medicine

BackgroundPET/MRI is an emerging imaging modality which enables the evaluation and quantification of biochemical processes in tissues, complemented with accurate anatomical information and low radiation exposure. In the framework of theragnosis, PET/MRI is of special interest due to its ability to delineate small lesions, adequately quantify them, and therefore to plan targeted therapies. The aim of this study was to validate the diagnostic performance of [68 Ga]Ga-DOTA-TOC PET/MRI compared to PET/CT in advanced disease paragangliomas and pheochromocytomas (PGGLs) to assess in which clinical settings, PET/MRI may have a greater diagnostic yield.MethodsWe performed a same-day protocol with consecutive acquisition of a PET/CT and a PET/MRI after a single [68 Ga]Ga-DOTA-TOC injection in 25 patients. Intermodality agreement, Krenning Score (KS), SUVmax (Standard Uptake Value), target-to-liver-ratio (TLR), clinical setting, location, and size were assessed.ResultsThe diagnostic accuracy with PET/MRI increased by 14.6% compared to PET/CT especially in bone and liver locations (mean size of new lesions was 3.73 mm). PET/MRI revealed a higher overall lesion uptake than PET/CT (TLR 4.12 vs 2.44) and implied an upward elevation of the KS in up to 60% of patients. The KS changed in 30.4% of the evaluated lesions (mean size 11.89 mm), in 18.4% of the lesions it increased from KS 2 on PET/CT to a KS ≥ 3 on PET/MRI and 24.96% of the lesions per patient with multifocal disease displayed a KS ≥ 3 on PET/MR, that were not detected or showed lower KS on PET/CT. In 12% of patients, PET/MRI modified clinical management.ConclusionsPET/MRI showed minor advantages over conventional PET/CT in the detection of new lesions but increased the intensity of SSRs expression in a significant number of them, opening the door to select which patients and clinical settings can benefit from performing PET/MRI.

Improving the detection of new lesions in multiple sclerosis with a cascaded 3D fully convolutional neural network approach.

Longitudinal magnetic resonance imaging (MRI) has an important role in multiple sclerosis (MS) diagnosis and follow-up. Specifically, the presence of new lesions on brain MRI scans is considered a robust predictive biomarker for the disease progression. New lesions are a high-impact prognostic factor to predict evolution to MS or risk of disability accumulation over time. However, the detection of this disease activity is performed visually by comparing the follow-up and baseline scans. Due to the presence of small lesions, misregistration, and high inter-/intra-observer variability, this detection of new lesions is prone to errors. In this direction, one of the last Medical Image Computing and Computer Assisted Intervention (MICCAI) challenges was dealing with this automatic new lesion quantification. The MSSEG-2: MS new lesions segmentation challenge offers an evaluation framework for this new lesion segmentation task with a large database (100 patients, each with two-time points) compiled from the OFSEP (Observatoire français de la sclérose en plaques) cohort, the French MS registry, including 3D T2-w fluid-attenuated inversion recovery (T2-FLAIR) images from different centers and scanners. Apart from a change in centers, MRI scanners, and acquisition protocols, there are more challenges that hinder the automated detection process of new lesions such as the need for large annotated datasets, which may be not easily available, or the fact that new lesions are small areas producing a class imbalance problem that could bias trained models toward the non-lesion class. In this article, we present a novel automated method for new lesion detection of MS patient images. Our approach is based on a cascade of two 3D patch-wise fully convolutional neural networks (FCNNs). The first FCNN is trained to be more sensitive revealing possible candidate new lesion voxels, while the second FCNN is trained to reduce the number of misclassified voxels coming from the first network. 3D T2-FLAIR images from the two-time points were pre-processed and linearly co-registered. Afterward, a fully CNN, where its inputs were only the baseline and follow-up images, was trained to detect new MS lesions. Our approach obtained a mean segmentation dice similarity coefficient of 0.42 with a detection F1-score of 0.5. Compared to the challenge participants, we obtained one of the highest precision scores (PPVL = 0.52), the best PPVL rate (0.53), and a lesion detection sensitivity (SensL of 0.53).

Image registration and appearance adaptation in non-correspondent image regions for new MS lesions detection.

Manual detection of newly formed lesions in multiple sclerosis is an important but tedious and difficult task. Several approaches for automating the detection of new lesions have recently been proposed, but they tend to either overestimate the actual amount of new lesions or to miss many lesions. In this paper, an image registration convolutional neural network (CNN) that adapts the baseline image to the follow-up image by spatial deformations and simulation of new lesions is proposed. Simultaneously, segmentations of new lesions are generated, which are shown to reliably estimate the real new lesion load and to separate stable and progressive patients. Several applications of the proposed network emerge: image registration, detection and segmentation of new lesions, and modeling of new MS lesions. The modeled lesions offer the possibility to investigate the intensity profile of new lesions.

Effect of routine intracerebral completion angiography on outcomes after transcarotid artery revascularization

ObjectiveCompletion cerebral angiography (CCA) after transcarotid artery revascularization (TCAR) has been used to identify distal embolization after stenting and serve as a measure of intraoperative quality control. Nevertheless, no general evidence has been reported regarding the benefit of performing routine CCA. The aim of the present study was to evaluate the potential risks and benefits of routine CCA. MethodsWe retrospectively reviewed the Vascular Quality Initiative database for TCAR from 2016 to 2021. The patients were divided into two groups: those with no CCA performed and those with CCA performed. The primary outcome was in-hospital stroke or death. The secondary outcomes included stroke, death, myocardial infarction, and a return to the operating room (RTOR). Clinically relevant and statistically significantly variables on univariable analysis were added to a logistic regression model clustered by center identifier. ResultsA total of 18,155 patients who had undergone TCAR were identified, of whom 11,607 (63.7%) had undergone routine CCA. The patients with routine CCA were more likely to have contralateral carotid occlusion and to have received general anesthesia. After adjusting for potential confounders, we found no differences in the risk of stroke/death (adjusted odds ratio [aOR], 1.03; 95% confidence interval [CI], 0.8-1.3; P = .820), stroke/transient ischemic attack (TIA; aOR, 1.00; 95% CI, 0.8-1.3; P = .998), stroke (aOR, 1.1; 95% CI, 0.8-1.4; P = .452), death (aOR, 0.98; 95% CI, 0.6-1.6; P = .953), myocardial infarction (aOR, 0.78; 95% CI, 0.5-1.2; P = .240), or RTOR (aOR, 1.5; 95% CI, 0.6-3.8; P = .412) between patients who had undergone CCA and those who had not. A subanalysis of the patients with new occlusions detected by CCA (69 patients [0.6%]; 19 not treated and 50 treated) indicated a higher risk of stroke/death for the patients with treated new occlusions (aOR, 7.1; 95% CI, 2.9-17.3; P < .001) and stroke/TIA (aOR, 5.8; 95% CI, 2.3-14.7; P < .001) than for the patients who had not undergone CCA. However, no differences were found in stroke/death (aOR, 3.3; 95% CI, 0.37-29.5; P = .283) or stroke/TIA (aOR, 3.1; 95% CI, 0.3-29.4; P = .327) for patients with nontreated new occlusions compared with patients who had not undergone CCA. ConclusionsIn the present retrospective study, routine performance of CCA was not beneficial, with no significant differences in in-hospital stroke or death detected. The detection of new lesions on CCA was rare. Moreover, identifying new occlusions using CCA was associated with higher odds of stroke or death when these new lesions were treated. Further studies are needed to define the etiology of the worse outcomes for patients undergoing intervention for lesions discovered using CCA and delineate the optimal timing for further imaging and intervention.

Is There a Role for Biomarkers in Surveillance of Pancreatic Neuroendocrine Neoplasms in Von Hippel-Lindau Disease?

Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by the development of multi-organ neoplasms. Among the manifestations of VHL are pancreatic neuroendocrine neoplasms (panNENs). In order to detect these lesions in a timely manner, patients are enrolled in a surveillance program, in accordance with the several existing VHL guidelines. However, these guidelines remain unclear about the role of biomarkers in diagnosing panNENs, despite the benefits a biomarker may offer regarding early detection of new lesions, thereby possibly limiting radiation exposure, and improving quality of life. The aim is to determine which biomarkers might be available in VHL patients and to assess their clinical relevance in diagnosing panNENs in VHL patients.We searched the databases of PubMed/Medline, Embase, and Web of Science to identify relevant articles. Seven studies assessing the diagnostic or prognostic value of biomarkers were included. The results from these studies were conflicting. Since no evident association between VHL-related panNENs and biomarkers was established in studies with larger study populations, currently biomarkers do not play a significant role in early detection or follow-up for panNENs in VHL patients. The absence of evidence underscores the need for specific research to address this unmet need.

Health Economic Impact of Software-Assisted Brain MRI on Therapeutic Decision-Making and Outcomes of Relapsing-Remitting Multiple Sclerosis Patients-A Microsimulation Study.

Aim: To develop a microsimulation model to assess the potential health economic impact of software-assisted MRI in detecting disease activity or progression in relapsing-remitting multiple sclerosis (RRMS) patients. Methods: We develop a simulated decision analytical model based on a hypothetical cohort of RRMS patients to compare a baseline decision-making strategy in which only clinical evolution (relapses and disability progression) factors are used for therapy decisions in MS follow-up, with decision-making strategies involving MRI. In this context, we include comparisons with a visual radiologic assessment of lesion evolution, software-assisted lesion detection, and software-assisted brain volume loss estimation. The model simulates clinical (EDSS transitions, number of relapses) and subclinical (new lesions and brain volume loss) disease progression and activity, modulated by the efficacy profiles of different disease-modifying therapies (DMTs). The simulated decision-making process includes the possibility to escalate from a low efficacy DMT to a high efficacy DMT or to switch between high efficacy DMTs when disease activity is detected. We also consider potential error factors that may occur during decision making, such as incomplete detection of new lesions, or inexact computation of brain volume loss. Finally, differences between strategies in terms of the time spent on treatment while having undetected disease progression/activity, the impact on the patient’s quality of life, and costs associated with health status from a US perspective, are reported. Results: The average time with undetected disease progression while on low efficacy treatment is shortened significantly when using MRI, from around 3 years based on clinical criteria alone, to 2 when adding visual examination of MRI, and down to only 1 year with assistive software. Hence, faster escalation to a high efficacy DMT can be performed when MRI software is added to the radiological reading, which has positive effects in terms of health outcomes. The incremental utility shows average gains of 0.23 to 0.37 QALYs over 10 and 15 years, respectively, when using software-assisted MRI compared to clinical parameters only. Due to long-term health benefits, the average annual costs associated with health status are lower by $1500–$2200 per patient when employing MRI and assistive software. Conclusions: The health economic burden of MS is high. Using assistive MRI software to detect and quantify lesions and/or brain atrophy has a significant impact on the detection of disease activity, treatment decisions, health outcomes, utilities, and costs in patients with MS.

Utility of Short Initial MRI Brain in Brain Metastases Patients Treated With Stereotactic Radiosurgery

The optimal timing of interval MRI surveillance following stereotactic radiosurgery (SRS) to detect most new lesions while asymptomatic and treatable by additional radiosurgery is unknown. As frequent MRI follow-up is an important patient burden and contributor to cost of care for brain metastases, we aimed to characterize the utility of early initial post-treatment MRI brain surveillance and to identify patient characteristics that might be used to risk-stratify patients who may benefit from early surveillance scans.An IRB-approved retrospective single-institution cohort of patients with brain metastases treated with frameless SRS was analyzed. Baseline demographics, treatment characteristics, and timing of follow-up MRI findings were reviewed in the electronic medical record. Fisher's exact test and Pearson's Chi-square test were used to compare proportions. Mann-Whitney-U test was used to compare continuous variables.One hundred consecutive patients treated from January 2018 - March 2020 were included, with plan for 6-week follow-up MRI post-treatment. Thirteen lacked follow-up MRI brain, leaving 87 for analysis. Median time to MRI was 6.7 weeks, with 78% of scans obtained less than 8 weeks post-SRS. Twenty-four (28%) patients had findings concerning for new or progressive disease on follow-up MRI. Nine were symptomatic. Of the 24, ten (42%) received SRS, 1 (8%) received whole brain radiotherapy (WBRT), 1 (4%) received surgery, 1 (4%) started systemic therapy, 7 received a short interval MRI scan, and 3 (12%) went to hospice. Of the 10 who received SRS, 3 were symptomatic, 6 had lesions ≥ 5 mm, and all 10 had lesions ≥ 5 mm. Of the 7 recommended for short interval MRI, 1 received SRS, 1 received WBRT, and 5 had no further evidence of disease progression, resuming routine surveillance. Comparing patients with suspicious findings to those with stable disease on follow-up MRI, there was a statistically significant difference (Table) in the distribution of histology (P = 0.02) and performance status (P = 0.047), but no difference in number of lesions, extra-cranial disease control, prior receipt of SRS, or use of targeted therapy or immune checkpoint inhibitors.A small but significant number of brain metastases patients treated with SRS may have additional therapy based on initial short interval surveillance MRI scans. Further investigation in larger cohorts may help identify patient characteristics that predispose to benefit from short interval MRI scans, and determine the value of earlier detection of new lesions compared with a longer interval to first scan.

P14.92 Combination of Tumor Treating Fields and CCNU chemotherapy as valuable option for the treatment of unresectable progressive glioblastoma: A case presentation

Abstract BACKGROUND Tumor Treating Fields (TTFields) are low intensity (1–3 V/cm) alternating electric fields with an intermediate frequency of 100–300 kHz. TTFields in addition to temozolomide (TMZ) after radiochemotherapy according to Stupp significantly increased progression-free survival (PFS), overall survival (OS) and long-term survival rates in patients with newly diagnosed glioblastoma (GBM) in the multicenter phase 3, EF-14 trial. Post-hoc analysis of the trial revealed that TTFields in combination with second-line therapy after first recurrence significantly prolonged OS compared to second-line therapy alone. We here report on a GBM patient with partial resection showing regressive volume of unresected, previously progressive tumor under combination therapy of TTFields and second-line CCNU chemotherapy. MATERIAL AND METHODS In November 2018, MRI of a 59-year-old female patient revealed a large heterogeneous space-occupying lesion in the left occipital region with clearly contrast-enhanced margin, perifocal edema and two smaller contrast-enhancing lesions in the splenium corporis callosi and right of the trigonum suboccipitale. While the tumor in the left occipital region was completely resected, lesions in the right hemisphere remained unresected. Histopathology identified MGMT-promoter methylated GBM. The patient received concomitant radiochemotherapy followed by adjuvant TMZ. However, after three cycles, the unresected tumor progressed, TMZ was exchanged by procarbazine/CCNU and TTFields therapy was initiated. After two cycles, chemotherapy was changed to only CCNU due to further progression while TTFields therapy was continued. RESULTS One year after diagnosis, MRI showed no contrast-enhancing tissue in the resection cavity and regressive perifocal edema while lesions in the right hemisphere remained stable. Under tolerable hematotoxicity CCNU was continued together with TTFields, to which the patient showed high adherence far beyond the suggested threshold of 75%. Control examination in February 2020 reported regressive tumor volume in the right hemisphere under CCNU/TTFields therapy. Until January 2021, the tumor regressed even further without the detection of new lesions. The patient is currently continuing CCNU together with TTFields, achieving an average usage of 84% over the last twelve months. CONCLUSION In the presented case, the combination of TTFields and CCNU was feasible and safe in progressive GBM. The patient showed radiological response and local tumor regression under the combination therapy, whereas the tumor had previously progressed under chemotherapy alone. In conclusion, the addition of TTFields to chemotherapy is a valuable treatment option to improve clinical and radiological outcome of patients with progressive GBM. This example of TTFields use in clinical practice encourages its use beyond tumor progression.

RADI-23. Exploring the optimal timing of routine initial surveillance MRI following treatment of brain metastases with stereotactic radiosurgery: a comparison of two approaches

PurposeTo measure the value of early initial surveillance MRI scans in patients with brain metastases undergoing stereotactic radiosurgery (SRS), as MRI scans are a significant cost and patient stressor.MethodsWe identified a retrospective cohort of patients with brain metastases treated with SRS and followed at a single institution with scheduled 6-week or 12-week initial surveillance MRI. Imaging interval was based on policy of different providers. Outcome measures included new/progressive lesions, salvage treatment, detection of new lesions before symptoms, and use of surgical resection.ResultsTwo hundred patients were included: 100 consecutive patients scanned with 6-week and 12-week imaging. Eighty-seven and 74 patients in each group had available follow-up imaging and were analyzed. Median time to MRI was 6.7 weeks and 13.5 (p<.001). No difference in primary site, prior SRS, number of treated brain metastases, or use of targeted therapy/immune checkpoint inhibitors was detected. A lower percentage of patients with 6-week MRI had controlled extracranial disease at initial treatment (30% vs 47%,p=.003). Twenty-eight percent with 6-week MRI had findings concerning for new/progressive disease, compared to 47% with 3-month MRI (p=0.01). Fifteen percent (10/87) with 6-week MRI underwent intervention (i.e. SRS, whole brain radiotherapy, or surgery) compared to 34% (20/74) with 12-week MRI (p=0.004). Of patients receiving SRS, a higher percentage had new/worsening neurologic symptoms (45% vs 30%) at follow-up although a lower percentage had new lesions >1cm (20% vs 50%) when discovered. One patient in each group underwent surgical salvage.ConclusionWhile shorter 6-week interval MRI surveillance post-SRS may detect new/progressive disease less frequently than 12-week MRI surveillance intervals, short interval MRI may be more likely to detect new/progressive lesions before symptoms develop. Surgical salvage was uncommon with either schedule. Further study may identify a high-risk subgroup who would benefit from early surveillance.

A novel total body digital photography smartphone application designed to detect and monitor skin lesions: a pilot study

&lt;p class="Body"&gt;Although some smartphone applications are designed for total body photography (TBP), few offer the specificity that enables self- as well as dermatologist-, detection of new lesions, or change in lesion color or in size as little as 1mm, on an ongoing basis. The aim of this study is to assess the sensitivity of a novel TBP application in the detection of changes to color and size of simulated skin lesions. Twenty-five subjects underwent one study visit. After baseline photography, new artificial markings were made or naturally occurring pigmented lesions located in any anatomical region were enhanced/enlarged, and a second matching set of photographs was then taken. From all 25 subjects, a total of 262 skin markings were evaluable. Of these, 241 (92%) were detected by the app, which resulted in an overall sensitivity of 92%. The high sensitivity establishes the app as capable of providing reliable self-TBP that allows detection and monitoring of new skin lesions or change in both size and color. This method greatly enhances the ability to accomplish ongoing self-monitoring and yet provides quality informing images to the dermatologist to assist in decision-making with the patient. &lt;/p&gt;

Does the Incremental Value of 123I-Metaiodobenzylguanidine SPECT/CT over Planar Imaging Justify the Increase in Radiation Exposure?

Planar scintigraphy with 123I-radiolabeled metaiodobenzylguanidine (123I-mIBG) is an important imaging modality to evaluate neuroblastoma. In recent years, Single Photon Emission Computed Tomography combined with Computed Tomography (SPECT/CT) has revolutionized nuclear medicine. Nevertheless, the addition of the CT has increased the patients' irradiation. We aimed to evaluate the incremental benefits of 123I-mIBG SPECT/CT over conventional planar imaging and to estimate the relative increase of radiation dose. We retrospectively evaluated the added value of 56 SPECT/CT performed in 40 children in terms of better characterization of the lesion and its locoregional extension, better lymph node staging, detection of new lesions, and elimination of false positives by a paired comparison between the planar images and the SPECT/CT ones. Then, we calculated the percentage contribution of the additional radiation of the CT in this hybrid imagery. In 88% (49 out of 56) of the examinations, SPECT/CT provided additional information, which was crucial in 20% of the cases. It allowed a better characterization of the lesion and its locoregional extension in 44 cases, a better lymph node staging in 28 cases, the detection of 33 new lesions, and the elimination of 9 false positives. The CT effective dose was significantly lower than the SPECT one. The average additional radiation exposure due to CT was 12% (4-23%). 123I-mIBG SPECT/CT has an undeniable added value that improves planar imaging interpretation and impacts patient management. These potential benefits would justify the low additional radiation induced by the CT.

Two-Step Digital Follow-up of Patients at High Risk for Melanoma: a Retrospective Analysis of 152 Patients

BackgroundDigital dermoscopy (DD) has been found to improve the accuracy of melanoma diagnosis in high-risk patients. A 2-step approach combining DD and total-body photography (TBP) can facilitate the detection of new lesions or early macroscopic changes in existing lesions. ObjectivesThe aim of this study was to determine the number of biopsies needed to diagnose melanoma and to describe the clinical and dermoscopic characteristics of melanoma diagnosed in patients with pigmented lesions under follow-up with DD and TBP. Patients and methodsRetrospective study of 152 patients with a high risk of melanoma who were followed using a 2-step digital approach at Hospital del Mar in Barcelona, Spain, between 2002 and 2016. We analyzed the characteristics of pigmented lesions excised after macroscopic changes were detected by periodic DD and TBD. ResultsBiopsy results of 99 lesions (84 dysplastic nevi, 13 melanomas, and 2 compound melanocytic nevi) showed a ratio of benign melanocytic lesions to melanomas of 1:6.6. The mean Breslow thickness was 0.19mm. Macroscopic changes were significantly more common in melanomas than in melanocytic nevi (P = .018). Dermoscopic findings associated with melanoma were asymmetric growth and focal structural changes (P < .001). The specific features associated with a diagnosis of melanoma were asymmetry (P < .001), a reverse pigment network (P = .011), atypical globules (P = .011), and polymorphous vessels (P = .045). ConclusionsTBP follow-up is a useful tool for the early diagnosis of melanoma. In our series, 50% of melanomas diagnosed during digital follow-up were detected by observation of a new lesion via TBP mapping or macroscopic changes in an existing lesion. Dermoscopic follow-up is essential in patients at high risk for melanoma as both melanocytic nevi and melanoma show a range of specific dermoscopic features, and a diagnosis of melanoma can only be based on a record of changes in the appearance of lesions during follow-up.

Seguimiento digitalizado combinado en población con alto riesgo de desarrollar un melanoma maligno: análisis retrospectivo de 152 pacientes

BackgroundDigital dermoscopy (DD) has been found to improve the accuracy of melanoma diagnosis in high-risk patients. A 2-step approach combining DD and total-body photography (TBP) can facilitate the detection of new lesions or early macroscopic changes in existing lesions. ObjectivesThe aim of this study was to determine the number of biopsies needed to diagnose melanoma and to describe the clinical and dermoscopic characteristics of melanoma diagnosed in patients with pigmented lesions under follow-up with DD and TBP. Patients and methodsRetrospective study of 152 patients with a high risk of melanoma who were followed using a 2-step digital approach at Hospital del Mar in Barcelona, Spain, between 2002 and 2016. We analyzed the characteristics of pigmented lesions excised after macroscopic changes were detected by periodic DD and TBD. ResultsBiopsy results of 99 lesions (84 dysplastic nevi, 13 melanomas, and 2 compound melanocytic nevi) showed a ratio of benign melanocytic lesions to melanomas of 1:6.6. The mean Breslow thickness was 0.19 mm. Macroscopic changes were significantly more common in melanomas than in melanocytic nevi (P = 0.018). Dermoscopic findings associated with melanoma were asymmetric growth and focal structural changes (P < 0.001). The specific features associated with a diagnosis of melanoma were asymmetry (P < 0.001), a reverse pigment network (P = 0.011), atypical globules (P = 0.011), and polymorphous vessels (P = 0.045). ConclusionsTBP follow-up is a useful tool for the early diagnosis of melanoma. In our series, 50% of melanomas diagnosed during digital follow-up were detected by observation of a new lesion via TBP mapping or macroscopic changes in an existing lesion. Dermoscopic follow-up is essential in patients at high risk for melanoma as both melanocytic nevi and melanoma show a range of specific dermoscopic features, and a diagnosis of melanoma can only be based on a record of changes in the appearance of lesions during follow-up.

A fully convolutional neural network for new T2-w lesion detection in multiple sclerosis.

Longitudinal magnetic resonance imaging (MRI) has an important role in multiple sclerosis (MS) diagnosis and follow-up. Specifically, the presence of new T2-w lesions on brain MR scans is considered a predictive biomarker for the disease. In this study, we propose a fully convolutional neural network (FCNN) to detect new T2-w lesions in longitudinal brain MR images. One year apart, multichannel brain MR scans (T1-w, T2-w, PD-w, and FLAIR) were obtained for 60 patients, 36 of them with new T2-w lesions. Modalities from both temporal points were preprocessed and linearly coregistered. Afterwards, an FCNN, whose inputs were from the baseline and follow-up images, was trained to detect new MS lesions. The first part of the network consisted of U-Net blocks that learned the deformation fields (DFs) and nonlinearly registered the baseline image to the follow-up image for each input modality. The learned DFs together with the baseline and follow-up images were then fed to the second part, another U-Net that performed the final detection and segmentation of new T2-w lesions. The model was trained end-to-end, simultaneously learning both the DFs and the new T2-w lesions, using a combined loss function. We evaluated the performance of the model following a leave-one-out cross-validation scheme. In terms of the detection of new lesions, we obtained a mean Dice similarity coefficient of 0.83 with a true positive rate of 83.09% and a false positive detection rate of 9.36%. In terms of segmentation, we obtained a mean Dice similarity coefficient of 0.55. The performance of our model was significantly better compared to the state-of-the-art methods (p<0.05). Our proposal shows the benefits of combining a learning-based registration network with a segmentation network. Compared to other methods, the proposed model decreases the number of false positives. During testing, the proposed model operates faster than the other two state-of-the-art methods based on the DF obtained by Demons.

67 Appraisal of Follow-up Protocols and Outcomes of High Risk Pancreatic Cancer Surveillance Programs: A Systematic Review and Meta-Analysis

INTRODUCTION: Individuals with familial or genetic predisposition are at high risk of pancreatic cancer (PC) and undergo screening. After baseline imaging, these high-risk individuals (HRIs) undergo regular follow-up through cross-sectional imaging, endoscopic ultrasound (EUS), or a combination of these modalities. The follow-up of HRIs is largely based on guidelines, and the evidence and consensus for optimal imaging modality and screening intervals are scarce. The current study is the first systematic review appraising various follow-up strategies among HRIs screened for PC for the detection of new lesions and progression of preexisting abnormalities. METHODS: Prospective studies on PC surveillance were analyzed to determine the imaging intervals and predominant modality-Cross sectional imaging: CT or MRI, or Combined EUS and cross sectional imaging. The outcomes of interest included incidence of new lesions where baseline was normal and progression of screen-prevalent lesions, defined as pre-existing abnormalities at baseline imaging. Follow-up was quantified as per 1000 patient-years (pt-yrs). A random effect model was used to calculate cumulative effect measures. The systematic review was performed in adherence with PRISMA guidelines and a preregistered protocol (Figure 1). RESULTS: 9 uncontrolled studies with 1438 subjects and 6274 pt-yrs of follow-up were analyzed; protocols included cross-sectional imaging (n = 4,4709 pt-yrs), or combined-EUS and cross sectional imaging (n = 5,1565 pt-yrs). HRIs with normal baseline were screened every 12 months, pooled radiologic incidence of 24.74 per 1000 pt-yrs [8.44–48.60, P &lt; 0.01] and diagnostic rate of advanced pathology of 1.06 per 1000 pt-yrs [0–3.99, P &lt; 0.08] (Figure 2). HRIs with screen-prevalent lesions were followed every 3–6 months and longer when stable, with cumulative progression rate of 19.47 per 1000 pt-yrs [1.05–52.98, P &lt; 0.01], and that of advanced pathology-1.54 per 1000 pt-yrs [0–7.55, P &lt; 0.01] (Figure 3). Subgroup analysis showed no significant difference in radiologic incidence or progression or in the histologic diagnosis of advanced pathologies between cross-sectional and combined follow-up protocols. CONCLUSION: Surveillance protocols exhibited significantly higher radiologic than histologic diagnostic rates. Though heterogeneity existed between studies, there was no significant difference in the diagnostic rates of incidence or progression between protocols employing predominately cross-sectional vs combined protocols of cross-sectional imaging and EUS.

Anal High-Grade Squamous Intraepithelial Lesions in Pharmacologically Immunocompromised Patients Followed in a Referral Center.

Information is lacking regarding anal/perianal precancerous lesions in referral cohorts of pharmacologically immunocompromised patients. The aim of this study is to evaluate the prevalence of anal/perianal high-grade squamous intraepithelial lesions in a referral cohort of patients on immunomodulator/immunosuppressive medications, who were assessed and followed with high-resolution anoscopy. This is a retrospective study. This study was conducted in a single anal neoplasia service from January 2012 to June 2017. Patients on chronic immunomodulator/immunosuppressive medications were included. Cases of concomitant immunosuppression due to HIV infection were excluded, and immunosuppression due to chemotherapy was not considered for this analysis. High-resolution anoscopy was performed. The primary outcome measured was the prevalence of anal/perianal high-grade squamous intraepithelial lesions in a referral cohort of pharmacologically immunocompromised patients. Fifty-four patients were included, of whom 40 were women (74%), with a mean age of 48 ± 17 years. A total of 232 high-resolution anoscopy examinations were performed in this cohort. At the first evaluation, 28 patients (52%) were diagnosed with anal and/or perianal high-grade squamous intraepithelial lesions (including 2 cases of perianal squamous cell carcinoma); 11 cases (20%) were new diagnoses. Ten of 46 patients (22%) with follow-up developed a new lesion (high-grade/cancer) during a median follow-up period of 17 (interquartile range, 6-28) months. Overall, 37 patients (69%) in our cohort had anal/perianal high-grade squamous intraepithelial lesions ever diagnosed (including previous history, first visit, and follow-up); 5 patients had perianal squamous cell carcinoma. At our center, 6% of the new referrals were known to be pharmacologically immunocompromised patients. The retrospective nature of this study, the heterogeneity of the cohort, and the absence of human papillomavirus testing were limitations of this study. The presence of anal and/or perianal high-grade squamous intraepithelial lesions or cancer detected by high-resolution anoscopy in this referral population was high, and the detection of new lesions suggests that long-term follow-up is needed. Patients on immunomodulator/immunosuppressive drugs represented only a small percentage of the new referrals to our center. See Video Abstract at http://links.lww.com/DCR/A748.