Occult Cancer Research Articles

Radiological features of screening-detected and interval breast cancers and subsequent survival in Eastern Finnish women.

Interval breast cancers are diagnosed between scheduled screenings and differ in many respects from screening-detected cancers. Studies comparing the survival of patients with interval and screening-detected cancers have reported differing results. The aim of this study was to investigate the radiological and histopathological features and growth rates of screening-detected and interval breast cancers and subsequent survival. This retrospective study included 942 female patients aged 50-69years with breast cancers treated and followed-up at Kuopio University Hospital between January 2010 and December 2016. The screening-detected and interval cancers were classified as true, minimal-signs, missed, or occult. The radiological features were assessed on mammograms by one of two specialist breast radiologists with over 15years of experience. A χ2 test was used to examine the association between radiological and pathological variables; an unpaired t test was used to compare the growth rates of missed and minimal-signs cancers; and the Kaplan-Meier estimator was used to examine survival after screening-detected and interval cancers. Sixty occult cancers were excluded, so a total of 882 women (mean age 60.4 ± 5.5years) were included, in whom 581 had screening-detected cancers and 301 interval cancers. Disease-specific survival, overall survival and disease-free survival were all worse after interval cancer than after screening-detected cancer (p < 0.001), with a mean follow-up period of 8.2years. There were no statistically significant differences in survival between the subgroups of screening-detected or interval cancers. Missed interval cancers had faster growth rates (0.47% ± 0.77%/day) than missed screening-detected cancers (0.21% ± 0.11%/day). Most cancers (77.2%) occurred in low-density breasts (< 25%). The most common lesion types were masses (73.9%) and calcifications (13.4%), whereas distortions (1.8%) and asymmetries (1.7%) were the least common. Survival was worse after interval cancers than after screening-detected cancers, attributed to their more-aggressive histopathological characteristics, more nodal and distant metastases, and faster growth rates.

Occult Breast Cancer Presenting as Sternum Pain.

Bone metastasis has been reported in up to 70% of patients with advanced breast cancer. A total of 55.76% of skeletal metastases in women were derived from breast cancer. However, patients with bone metastasis from an occult primary breast cancer are a rare subset of patients. Here, we present the case of a 38-year-old woman who had sternum pain for 4 months. A whole-body PET-CT scan revealed that the FDG uptake of both the sternum and internal mammary node was significantly increased. The final diagnosis of occult breast cancer was established by immunohistochemical (IHC) staining, which is of great significance for identifying the origin of a metastatic tumor despite no visualized lesions of mammary glands.

Anaerobic gram-negative rod bacteremia as a marker of gastrointestinal cancer in Japanese patients: a single-center retrospective study.

Gram-negative rod (GNR) bacteremia has been suggested as a clinical marker of occult cancer; however, no studies are available in this regard in the Japanese population. Here, we investigated the risk factors for gastrointestinal cancer with GNR bacteremia. Patients with GNR bacteremia admitted to St. Luke's International Hospital between January 2011 and July 2021 were included. The clinical data of patients with and without cancer, 1 year before and after GNR bacteremia diagnosis, were compared. Univariate analysis was performed using χ2 and Fisher's exact tests for categorical variables and the Mann-Whitney U test for continuous variables, while multivariable analysis was performed using logistic regression analysis, and a P of <0.05 was considered statistically significant. Of 2,296 GNR bacteremia-positive patients, 96 were associated with gastrointestinal cancer, and univariate analysis showed significant differences between the gastrointestinal cancer and comparison groups in terms of mean body mass index (BMI; 20.5 vs. 21.8 kg/m2), Enterobacterales detection (64.6% vs. 81.3%), and anaerobic GNR detection (24.0% vs. 8.5%). Thirty-five (36%) and 61 (64%) patients had upper and lower gastrointestinal cancer, respectively. There were 23 patients with anaerobic GNR bacteremia related to 24 strains (upper and lower gastrointestinal cancer, 5 and 18 cases, respectively). Multivariate analysis identified anaerobic GNR [odds ratio, 3.440; 95% confidence interval (CI): 2.085-5.675, P<0.001] as a significant risk factor for cancer. Anaerobic GNR in blood cultures may be a risk factor for gastrointestinal cancer. Therefore, it is necessary consider cancer workup, such as endoscopy, for patients with anaerobic GNR bacteremia.

Triple-negative occult breast cancer: A case report

The phenomenon of occult breast cancer represents a rare scenario raising crucial questions regarding its clinical presentation, diagnosis, and timely treatment. The therapeutic challenge can become even more difficult in the specific case of triple-negative breast cancer. This article presents the case report of a patient who had a palpable axillary nodule during a routine gynecological exam. A core needle biopsy confirmed that the patient had metastatic ductal carcinoma of mammary origin, which was triple-negative. Despite several diagnostic procedures, there was no evidence of a primary tumor in the breast clinically or in imaging studies. The patient underwent neoadjuvant chemotherapy with satisfying outcomes and later, to radical surgery therapy regardless of the feasibility of receiving a conservative treatment.

High-resolution diffusion-weighted MRI plus mammography for detecting clinically occult breast cancers in women with dense breasts

PurposeTo compare the performance of mammography, high-resolution DW-MRI, DCE-MRI, and their combinations in detecting clinically occult breast cancer in women with dense breasts. Method544 breasts from 281 consecutive asymptomatic women with dense breasts were retrospectively identified. They underwent breast MRI for preoperative evaluation of breast cancers (n = 214) or as supplemental screening (n = 67) including DCE-MRI and DW-MRI (b values, 0 and 1000 sec/mm2; in-plane resolution, 1.1 × 1.1 mm2 and 1.3 × 1.3 mm2; section thickness, 3 mm), in addition to mammography. Three readers independently reviewed each examination on a per-breast basis. Histopathology and at least two year of imaging follow-up served as the gold standard. The sensitivities and specificities of different imaging modalities were compared using McNemar test. Results230 of 544 breasts (42 %) had malignant lesions. The sensitivity of DW-MRI was higher than that of mammography (77.0 % vs 57.9 %; adjusted p < 0.001), but lower than that of DCE-MRI (84.8 %; adjusted p = 0.014). The specificity of DW-MRI was comparable to those of mammography (98.1 % vs 99.1 %; adjusted p > 0.999) and DCE-MRI (97.1 %; adjusted p > 0.999). DW-MRI plus mammography had a comparable sensitivity and specificity to those of DCE-MRI plus mammography (88.6 % vs 90.9 % and 97.1 % vs 96.2 %; adjusted p > 0.999 for both). ConclusionsHigh-resolution DW-MRI had a sensitivity higher than mammography and lower than DCE-MRI. Nevertheless, DW-MRI plus mammography showed a comparable sensitivity and specificity to DCE-MRI plus mammography for detecting clinically occult cancers in women with dense breasts.

Isolated metastasis to the scalp in occult breast cancer: a clinical case

Isolated metastasis to the scalp in occult breast cancer: a clinical case

Cancer screening in hospitalized ischemic stroke patients: a multicenter study focused on multiparametric analysis to improve management of occult cancers.

The reciprocal promotion of cancer and stroke occurs due to changes in shared risk factors, such as metabolic pathways and molecular targets, creating a "vicious cycle." Cancer plays a direct or indirect role in the pathogenesis of ischemic stroke (IS), along with the reactive medical approach used in the treatment and clinical management of IS patients, resulting in clinical challenges associated with occult cancer in these patients. The lack of reliable and simple tools hinders the effectiveness of the predictive, preventive, and personalized medicine (PPPM/3PM) approach. Therefore, we conducted a multicenter study that focused on multiparametric analysis to facilitate early diagnosis of occult cancer and personalized treatment for stroke associated with cancer. Admission routine clinical examination indicators of IS patients were retrospectively collated from the electronic medical records. The training dataset comprised 136 IS patients with concurrent cancer, matched at a 1:1 ratio with a control group. The risk of occult cancer in IS patients was assessed through logistic regression and five alternative machine-learning models. Subsequently, select the model with the highest predictive efficacy to create a nomogram, which is a quantitative tool for predicting diagnosis in clinical practice. Internal validation employed a ten-fold cross-validation, while external validation involved 239 IS patients from six centers. Validation encompassed receiver operating characteristic (ROC) curves, calibration curves, decision curve analysis (DCA), and comparison with models from prior research. The ultimate prediction model was based on logistic regression and incorporated the following variables: regions of ischemic lesions, multiple vascular territories, hypertension, D-dimer, fibrinogen(FIB), and hemoglobin(Hb). The area under the ROC curve (AUC) for the nomogram was 0.871 in the training dataset and 0.834 in the external test dataset. Both calibration curves and DCA underscored the nomogram's strong performance. The nomogram enables early occult cancer diagnosis in hospitalized IS patients and helps to accurately identify the cause of IS, while the promotion of IS stratification makes personalized treatment feasible. The online nomogram based on routine clinical examination indicators of IS patients offered a cost-effective platform for secondary care in the framework of PPPM. The online version contains supplementary material available at 10.1007/s13167-024-00354-8.

Occult cancer in patients with unprovoked venous thromboembolism: A nested case-control study.

Detecting occult cancer in patients with unprovoked venous thromboembolism (VTE) remains a significant challenge. Our objective was to investigate the potential predictive role of coagulation-related biomarkers in the diagnosis of occult malignancies. We conducted a nested case-control study with a 1-year prospective cohort of 214 patients with unprovoked VTE, with a focus on identifying occult cancer. At the time of VTE diagnosis, we measured various biomarkers, including soluble P-selectin (sP-selectin), dimerized plasmin fragment D (D-dimer), platelets, leukocytes, hemoglobin, total extracellular vesicles (EVs), EVs expressing tissue factor on their surface (TF+EVs), and EVs expressing P-selectin on their surface (Psel+EVs) in all participants. We observed statistically significant increased levels of sP-selectin (P = .015) in patients with occult cancer. Despite an increase in Psel+EVs, TF+EVs, D-dimer, and platelets within this group, however, no significant differences were found. When sP-selectin exceeded 62 ng/mL and D-dimer surpassed 10,000 µg/L, the diagnosis of occult cancer demonstrated a specificity of up to 91% (95% CI, 79.9%-96.7%). The combination of sP-selectin and D-dimer can be a valuable biomarker in detecting occult cancer in patients with unprovoked VTE. Further research is necessary to ascertain whether easily measurable biomarkers such as sP-selectin and D-dimer can effectively distinguish between patients who have VTE with and without hidden malignancies.

Systematic review and meta-analysis of studies comparing baseline D-dimer level in stroke patients with or without cancer: Strength of current evidence.

D-dimer levels are increased in stroke and cancer. Cancer patients are at a higher risk of stroke. However, the evidence is unclear if high D-dimer in stroke patients can suggest the diagnosis of concomitant cancer or the development of stroke in a cancer patient. The objective is to assess the evidence available on the baseline D-dimer level in stroke patients with and without cancer. We conducted the systematic review and meta-analysis using the Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched PUBMED, Cochrane, ScienceDirect, and Scopus for potentially eligible articles published till June 2023. All the review steps were iterative and done independently by two reviewers. The Newcastle-Ottawa scale tool was used to assess the quality of included studies for case control and cohort studies and the Agency for Healthcare Research and Quality tool for cross-sectional studies. The qualitative synthesis is presented narratively, and quantitative synthesis is shown in the forest plot using the random effects model. I2 of more than 60% was considered as high heterogeneity. The searches from all the databases yielded 495 articles. After the study selection process, six papers were found eligible for inclusion in the qualitative and quantitative synthesis. In the present systematic review, 2651 patients with ischemic infarcts are included of which 404 (13.97%) patients had active cancer while 2247 (86.02%) did not. The studies included were of high quality and low risk of bias. There were significantly higher baseline D-dimer levels in stroke patients with cancer than in non-cancer patients with a mean difference of 4.84 (3.07-6.60) P < 0.00001. D-dimer is a simple and relatively non-expensive biomarker that is increased to significant levels in stroke patients, who have cancer and therefore may be a tool to predict through screening for active or occult cancer in stroke patients.

Abstract TP225: Prevalence of Patent Foramen Ovale in Patients With Cancer-Related Stroke

Background and Purpose: Cancer increases the risk for acute ischemic stroke (AIS) and deep venous thrombosis. The role of paradoxical embolization as a stroke etiology in patients with cancer is uncertain. Our study investigated the relationship between cancer-related stroke and the presence of a patent foramen ovale (PFO). Methods: We included AIS patients hospitalized at our comprehensive stroke center between January 2015 and December 2020 with available PFO status as detected on transesophageal echocardiography. Active cancer, including cancer known at the time of stroke as well as occult cancer newly diagnosed within one year after stroke, were retrospectively identified. The association between PFO status and active cancer was assessed with multivariable logistic regression and reported using adjusted odds ratios (aOR) and their 95% confidence intervals (CI). Results: Among 2236 AIS patients (median age 68.3 years, female sex 36.4%), 103 (4.6%) had active cancer, of whom 24 (23%) were diagnosed with PFO. This included 32 patients (1.4%) with occult cancer, of whom 19% were diagnosed with PFO. Conversely, among 2133 AIS patients without active cancer, 774 were diagnosed with PFO (36%). In multivariable analysis (Fig 1), the absence of PFO was associated with active cancer (aOR 2.62, 95% CI 1.28-5.38). This association appeared stronger when patients older than 80 years of age were excluded (aOR 3.06, 95% CI 1.42 - 6.58) and persisted among patients with occult cancer at the time of AIS (aOR 5.39, 95% CI 1.18-24.74). Conclusions: In patients with AIS, PFO was diagnosed more commonly among patients without cancer than those with cancer. This might be due to cancer-related stroke being related to arterial coagulopathy rather than paradoxical emboli resulting from venous thrombi. Further studies are needed to confirm these findings and to assess the diagnostic role of PFO in patients with cancer and AIS.

Abstract 136: The Incidence of Newly Diagnosed Cancer After a First-Ever Episode of Cerebral Venous Thrombosis: A Registry- and Population-Based Cohort Study

Introduction: Active cancer is a known risk factor for cerebral venous thrombosis (CVT), but it is unknown whether CVT is also associated with occult cancer. We evaluated the incidence of newly diagnosed cancer after CVT. Methods: We performed a registry- and population-based cohort study using the Dutch hospital discharge registry. Patients admitted to any Dutch hospital between 1997 and 2020 with a first episode of CVT were identified using ICD-9 and ICD-10 codes. Patients with a history of cancer and patients diagnosed with cancer during admission for the index CVT were excluded. We calculated the cumulative incidence of cancer after CVT with death as a competing risk. Standardized incidence ratios (SIRs) were calculated relative to a control group matched by age, sex, and calendar year with data from the Netherlands Cancer Registry. Results: We identified 2649 patients, 1856 (70%) were women and the median age was 44 (IQR 31-56) years. Cancer was diagnosed in 119 patients during follow-up (median duration 4.7 [IQR 1.9-8.9] years), of which hematologic (24%) and gastrointestinal tract (20%) cancers were the most common. The cumulative incidence of cancer in the overall cohort was 5.9% (95%CI 4.8-7.2) after 10 years. The highest cumulative incidence after 10 years was observed in patients ≥50 years (10.5% [95%CI 7.9-13.4]) and in men (9.9% [95%CI 7.1-13.1]). Patients with CVT had an increased rate of cancer compared to controls during the entire follow-up, but the difference narrowed over time (SIR 3.4 [95%CI 2.4-4.5] at 1 year and 1.4 [1.1-1.7] at 10 years). The rate was increased in both patients younger than 50 (SIR 6.7 [95%CI 4.0-10.6] at 1 year and 1.7 [1.2-2.3] at 10 years) and older than 50 years (SIR 2.4 [95%CI 1.5-3.6] at 1 year and 1.2 [0.96-1.6] at 10 years), as well as in men (SIR 3.6 [95%CI 2.2-5.6] at 1 year and 1.7 [1.2-2.2] at 10 years) and women (SIR 3.2 [95%CI 2.0-4.8] at 1 year and 1.2 [0.9-1.6] at 10 years). Conclusion: Patients with CVT have an increased risk of cancer compared to peers from the general population, regardless of age group or sex. The absolute risk of cancer was highest in older patients and men, while the relative risk was highest in younger patients. These results support the need for further research on screening for occult cancer in patients with CVT.

Occult breast cancer: Unusually detected by left para sternal adenopathy

Occult breast cancer: Unusually detected by left para sternal adenopathy

Abstract B022: A platform to characterize hepatic immunity reveals variation in hepatic infiltration of tumor expanded T cells in “localized” PDAC

Abstract Even in its earliest stages, pancreatic ductal adenocarcinoma (PDAC) is an essentially incurable disease due to the presence of disseminated, yet radiographically occult cancer cells in the setting of an otherwise “localized” primary tumor. The vast majority (~80%) of patients who undergo curative-intent surgery develop liver metastases, often within six months of surgery, and these hepatic metastases dominate survival outcomes, even in the presence of multisite recurrence. What drives hepatic organotropism remains unknown, in large part due to the exclusion of “normal” liver tissue from PDAC biobanking programs. While recent work in animal models suggests that suppression of the hepatic immune microenvironment may facilitate metastatic progression, confirmatory studies in human patients are lacking, due to a paucity of relevant model systems. To address this deficit, we developed an experimental pipeline to profile hepatic immunity at single-cell resolution vis-à-vis the peripheral and intratumoral immune compartments. We hypothesized that this platform could be leveraged to identify tissue- and patient-specific immunophenotypes associated with hepatic recurrence prior to the development of overt metastases. Patients with localized PDAC at Duke University were enrolled in an IRB-approved (Pro00108288) biobanking program to obtain multisegment liver biopsies, primary tumor specimen, and peripheral blood at the time of curative-intent resection. Immune (CD45+) cells were sorted following enzymatic digestion (tissues) or Ficoll separation (blood) and single-cell gene expression and T cell receptor libraries were created. Data was processed using CellRanger and aligned, filtered, and normalized using R. In total, we identified 32 unique immune cell populations conserved across patients, with both shared and site-specific cell types identified in the T cell, B cell, NK cell, and myeloid compartments. Additionally, we identified expanded T cell clones within the tumor microenvironment and traced a subset of these clonotypes to the premetastatic liver. These tumor-expanded T cells (TTE cells) presumably arise from recognition of a specific tumor antigen, which then instigates activation and proliferation of the clone. Notably, we identified a subset of our patients without known liver metastases who nonetheless demonstrated hepatic infiltration of TTE cells. While the significance of these hepatic TTE cells is still unclear, we hypothesize that this is evidence of a primed immune response to tumor antigens already present in the liver at the time of surgery. This experimental platform has now been implemented within an ongoing window-of-opportunity trial (NCT05634720) testing neoadjuvant hepatic artery chemotherapy in patients undergoing resection of localized PDAC. The correlative scientific objectives will focus on quantifying the variation of hepatic TTE infiltration across patients, determining the function and activation state of hepatic TTE cells, and testing the association between hepatic TTE cell infiltration and clinical outcomes. Citation Format: Elishama N. Kanu, Ashley A. Fletcher, Jiayin Bao, Austin M. Eckhoff, Karrie Comatas, Tao Wang, Bin-Jin Hwang, Michael E. Lidsky, Sabino Zani, Dan G. Blazer, Peter J. Allen, Zhicheng Ji, Daniel P. Nussbaum, Erika J. Crosby. A platform to characterize hepatic immunity reveals variation in hepatic infiltration of tumor expanded T cells in “localized” PDAC [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Pancreatic Cancer; 2023 Sep 27-30; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(2 Suppl):Abstract nr B022.

Autoantibodies Against Bestrophin in Non-Paraneoplastic Acute Exudative Polymorphous Vitelliform Maculopathy.

Acute exudative polymorphous vitelliform maculopathy (AEPVM) has recently been identified as a paraneoplastic manifestation of various cancers. Yet, the first reported cases of AEPVM in the literature were reported in seemingly healthy individuals. It is not clear whether those individuals harbored unidentified mutations or occult cancers, or truly represented a separate subset of AEPVM. Here, we report two cases of mutation-negative, autoantibody-positive non-paraneoplastic AEPVM. We present multimodal ocular imaging to demonstrate the presentation of this subset of AEPVM. [Ophthalmic Surg Lasers Imaging Retina 2024;55:51-54.].

Thrombocytopenia as first presentation of occult breast cancer. First case described

Occult breast carcinoma is very rare and will appear initially as metastatic with undetectable primary breast tumor. This is the first case described in the literature with thrombocytopenia as first clinical symptom.

Obesity-Associated Breast Cancer: Analysis of Risk Factors and Current Clinical Evaluation.

Several studies show that a significantly stronger association is obvious between increased body mass index (BMI) and higher breast cancer incidence. Additionally, obese and postmenopausal women are at higher risk of all-cause and breast cancer-specific mortality compared with non-obese women with breast cancer. In this context, increased levels of estrogens, excessive aromatization activity of the adipose tissue, overexpression of pro-inflammatory cytokines, insulin resistance, adipocyte-derived adipokines, hypercholesterolemia, and excessive oxidative stress contribute to the development of breast cancer in obese women. Genetic evaluation is an integral part of diagnosis and treatment for patients with breast cancer. Despite trimodality therapy, the four-year cumulative incidence of regional recurrence is significantly higher. Axillary lymph nodes as well as primary lesions have diagnostic, prognostic, and therapeutic significance for the management of breast cancer. In clinical setting, because of the obese population primary lesions and enlarged lymph nodes could be less palpable, the diagnosis may be challenging due to misinterpretation of physical findings. Thereby, a nomogram has been created as the "Breast Imaging Reporting and Data System" (BI-RADS) to increase agreement and decision-making consistency between mammography and ultrasonography (USG) experts. Additionally, the "breast density classification system," "artificial intelligence risk scores," ligand-targeted receptor probes," "digital breast tomosynthesis," "diffusion-weighted imaging," "18F-fluoro-2-deoxy-D-glucose positron emission tomography," and "dynamic contrast-enhanced magnetic resonance imaging (MRI)" are important techniques for the earlier detection of breast cancers and to reduce false-positive results. A high concordance between estrogen receptor (ER) and progesterone receptor (PR) status evaluated in preoperative percutaneous core needle biopsy and surgical specimens is demonstrated. Breast cancer surgery has become increasingly conservative; however, mastectomy may be combined with any axillary procedures, such as sentinel lymph node biopsy (SLNB) and/or axillary lymph node dissection whenever is required. As a rule, SLNB-guided axillary dissection in breast cancer patients who have clinically axillary lymph node-positive to node-negative conversion following neoadjuvant chemotherapy is recommended, because lymphedema is the most debilitating complication after any axillary surgery. There is no clear consensus on the optimal treatment of occult breast cancer, which is much discussed today. Similarly, the current trend in metastatic breast cancer is that the main palliative treatment option is systemic therapy.

Comparison characteristic visibility of the lesions with automated whole breast ultrasound and handheld breast ultrasound in screening situation

Background: Screening mammography and additional ultrasound are effective in detecting occult cancer. We know that handheld breast ultrasound (HHUS) depends on the operator. In comparison, automated whole breast ultrasound (ABUS) decreases these disadvantages of ultrasound procedures and can increase its sensitivity to cancer detection rates, but the results showed such studies, especially masses’ characteristics, are different. Our study wants to evaluate the features of the lesions in all aspects of the masses by using ABUS compared to HHUS to increase overall interpretation confidence. Objective: Comparison of visible breast lesions between ABUS and HHUS. Materials and Methods: Retrospective analysis was conducted with 168 screening mammography cases, the undergoing ABUS and HHUS interpreted as the detected lesion, mass characteristic and BI-RADS between October 2017 to May 2018. The investigator reviewed the pathologic or the 2-year follow-up from hand-held ultrasound results. The agreement measurements were assessed, using SD, ICC, percent agreement and Cohen kappa coefficient. Results: Comparison of the mass's details between two radiologists by using ABUS, ICCs for the location and individual size of the lesion had good reliability. Localization (κ = 0.81) and BI-RADS (κ = 0.82) showed almost perfect agreement showing substantial agreement for mass margin (κ = 0.78), moderate agreement for mass shape (κ = 0.48) as well as 95% agreement for mass orientation. Intra-rater reliability between two modalities also revealed concordance in both radiologists in important ways for breast mass interpretation. Conclusion: ABUS can detect lesions, give accurate locations, certain mass size and a few characteristics, is acceptable for screening and monitor detected lesions.

Methods for improving colorectal cancer annotation efficiency for artificial intelligence-observer training.

Missing occult cancer lesions accounts for the most diagnostic errors in retrospective radiology reviews as early cancer can be small or subtle, making the lesions difficult to detect. Second-observer is the most effective technique for reducing these events and can be economically implemented with the advent of artificial intelligence (AI). To achieve appropriate AI model training, a large annotated dataset is necessary to train the AI models. Our goal in this research is to compare two methods for decreasing the annotation time to establish ground truth: Skip-slice annotation and AI-initiated annotation. We developed a 2D U-Net as an AI second observer for detecting colorectal cancer (CRC) and an ensemble of 5 differently initiated 2D U-Net for ensemble technique. Each model was trained with 51 cases of annotated CRC computed tomography of the abdomen and pelvis, tested with 7 cases, and validated with 20 cases from The Cancer Imaging Archive cases. The sensitivity, false positives per case, and estimated Dice coefficient were obtained for each method of training. We compared the two methods of annotations and the time reduction associated with the technique. The time differences were tested using Friedman's two-way analysis of variance. Sparse annotation significantly reduces the time for annotation particularly skipping 2 slices at a time (P < 0.001). Reduction of up to 2/3 of the annotation does not reduce AI model sensitivity or false positives per case. Although initializing human annotation with AI reduces the annotation time, the reduction is minimal, even when using an ensemble AI to decrease false positives. Our data support the sparse annotation technique as an efficient technique for reducing the time needed to establish the ground truth.

RWD91 Hospital Efficiency Impact of Spectral CT Versus Conventional CT in Diagnosis of Patients Suspected of Occult Cancer in the UK

RWD91 Hospital Efficiency Impact of Spectral CT Versus Conventional CT in Diagnosis of Patients Suspected of Occult Cancer in the UK

The Novel Use of Magtrace in Chest Masculinizing Transgender Top Surgery

Summary: Chest masculinization is the most common surgery performed in transgender men, and although incidence of occult cancer is lower than in cis-gender women receiving mastectomy or reduction mammoplasties, the incidence of high-risk lesions is comparable. In patients with concerns for occult malignancy, Magtrace is a nonradioactive tracer available to assist management for its delayed sentinel lymph node mapping capabilities. We present the first case report using Magtrace before masculinizing mastectomies in a transgender man.