Comprehensive Prostate Fluid-Based Spectral Libraries for Enhanced Protein Detection in Urine.

Biofluids contain molecules in circulation and from nearby organs that can be indicative of disease states. Characterizing the proteome of biofluids with DIA-MS is an emerging area of interest for biomarker discovery; yet, there is limited consensus on DIA-MS data analysis approaches for analyzing large numbers of biofluids. To evaluate various DIA-MS workflows, we collected urine from a clinically heterogeneous cohort of prostate cancer patients and acquired data in DDA and DIA scan modes. We then searched the DIA data against urine spectral libraries generated using common library generation approaches or a library-free method. We show that DIA-MS doubles the sample throughput compared to standard DDA-MS with minimal losses to peptide detection. We further demonstrate that using a sample-specific spectral library generated from individual urines maximizes peptide detection compared to a library-free approach, a pan-human library, or libraries generated from pooled, fractionated urines. Adding urine subproteomes, such as the urinary extracellular vesicular proteome, to the urine spectral library further improves the detection of prostate proteins in unfractionated urine. Altogether, we present an optimized DIA-MS workflow and provide several high-quality, comprehensive prostate cancer urine spectral libraries that can streamline future biomarker discovery studies of prostate cancer using DIA-MS.

Fructose malabsorption and fructan malabsorption are associated in patients with irritable bowel syndrome.

BACKGROUND: Food malabsorption and intolerance is implicated in gastrointestinal symptoms among patients with irritable bowel syndrome (IBS). Key triggers include fructose and fructan. Prior studies examined fructose and fructan malabsorption separately in IBS patients. None have concurrently assessed both within the same patient group. We aimed to investigate the association between fructose and fructan malabsorption in the same patients with IBS using hydrogen breath testing (HBT). METHODS: We retrospectively identified patients with IBS who underwent fructose and fructan HBTs and abstracted their results from the electronic medical record. Fructose and fructan HBTs were performed by administering a 25 g fructose solution or 10 g fructan solution, followed by breath hydrogen readings every 30 min for 3 h. Patients were positive for fructose or fructan malabsorption if breath hydrogen levels exceeded 20 ppm. RESULTS: Of 186 IBS patients, 71 (38.2%) were positive for fructose malabsorption and 91 (48.9%) were positive for fructan malabsorption. Of these patients, 42 (22.6%) were positive for fructose malabsorption and fructan malabsorption. Positive fructose HBT readings were significantly associated with positive fructan HBT readings (p = 0.0283). Patients positive for fructose malabsorption or fructan malabsorption had 1.951 times higher odds of testing positive for the other carbohydrate. CONCLUSIONS: Our results reveal a clinically significant association between fructose malabsorption and fructan malabsorption in patients with IBS. Fructan malabsorption should be assessed in patients with fructose malabsorption, and vice versa. Further studies are required to identify the mechanisms underlying our findings.

Urethra contouring on computed tomography urethrogram versus magnetic resonance imaging for stereotactic body radiotherapy in prostate cancer.

Accurate urethra contouring is critical in prostate SBRT. We compared urethra contouring on CT-urethrogram and T2-weighted MRI. The dice similarity coefficient, Jaccard index, Hausdorff distance and mean distance to agreement were evaluated. All four metrics indicate better agreement and less variability in urethra contouring on CT-urethrogram, compared to T2-weighted MRI.

Randomized Trial of Concomitant Hypofractionated Intensity Modulated Radiation Therapy Boost Versus Conventionally Fractionated Intensity Modulated Radiation Therapy Boost for Localized High-Risk Prostate Cancer (pHART2-RCT).

PURPOSE: The aim of this work is to report on the results of a phase 2 randomized trial of moderately hypofractionated (MH) versus conventionally fractionated (CF) radiation therapy to the prostate with elective nodal irradiation. METHODS AND MATERIALS: This was a single-center, prospective, phase 2 randomized study. Patients with high-risk disease (cT3, prostate-specific antigen level >20 ng/mL, or Gleason score 8-10) were eligible. Patients were randomized to either MH using a simultaneous integrated boost (68 Gy in 25 fractions to prostate; 48 Gy to pelvis) or CF (46 Gy in 23 fractions with a sequential boost to the prostate of 32 Gy in 16 fractions), with long-term androgen deprivation therapy. The primary endpoint was grade ≥2 acute gastrointestinal (GI) and genitourinary (GU) toxicity (Common Terminology Criteria for Adverse Events version 3.0). Secondary endpoints included late GI and GU toxicity, quality of life, and oncologic outcomes. RESULTS: One-hundred eighty patients were enrolled; 90 were randomized to and received MH and 90 to CF. The median follow-up was 67.4 months. Seventy-five patients (41.7%) experienced a grade ≥2 acute GI and/or GU toxicity, including 34 (37.8%) in the MH and 41 (45.6%) in the CF arms, respectively (P = .29). Late grade ≥2 GI (P = .07) and GU (P = .25) toxicity was not significantly different between arms; however, late grade ≥3 GI toxicity was worse in the MH group (P = .01). There were no statistically significant quality-of-life differences between the 2 treatments. There were no statistically significant differences observed in cumulative incidence of biochemical failure (P = .71) or distant metastasis (P = .31) and overall survival (P = .46). CONCLUSIONS: MH to the prostate and pelvis with androgen deprivation therapy for men with high-risk localized prostate cancer was not significantly different than CF with regard to acute toxicity, quality of life, and oncologic efficacy. However, late grade ≥3 GI toxicity was more common in the MH arm.

The readability of online patient education materials on maxillomandibular advancement surgery.

STUDY OBJECTIVES: Maxillomandibular advancement (MMA) is an effective surgical option for patients suffering from obstructive sleep apnea (OSA). As a relatively new treatment option, patients may turn to the Internet to learn more. However, online patient education materials (OPEMs) on MMA may be written at a higher literacy level than recommended for patients. The aim of this study was to analyze the readability of OPEMs on MMA. METHODS: A Google search of "maxillomandibular advancement" was performed, and the first 100 results were screened. Websites that met eligibility criteria were analyzed for their readability using the Automated Readability Index (ARI), Coleman-Liau Index (CLI), Flesch-Kincaid Grade Level (FKGL), Gunning Fog (GF), and Simple Measure of Gobbledygook (SMOG) and compared to the recommended sixth-grade reading level using one-tailed t tests. Readability scores were compared based on the type of website, including hospitals/universities or physician clinics, using ANOVA tests. RESULTS: The mean (SD) for ARI, CLI, FKGL, GF, and SMOG was 11.91 (2.43), 13.42 (1.81), 11.91 (2.06), 14.32 (2.34), and 13.99 (1.56), respectively. All readability scores were significantly higher than a sixth-grade reading level (p < 0.001). After comparing readability scores between different website types (university/hospital, clinic, and other), there was no statistical difference found. CONCLUSIONS: The available OPEMs on MMA surgery for OSA are above the recommended sixth-grade reading level. Identifying and reducing the gap between the reading levels of OPEMs and the reading level of the patient are needed to encourage a more active role, informed decisions, and better patient satisfaction.

Spatial subsetting enables integrative modeling of oral squamous cell carcinoma multiplex imaging data.

Oral squamous cell carcinoma (OSCC), a prevalent and aggressive neoplasm, poses a significant challenge due to poor prognosis and limited prognostic biomarkers. Leveraging highly multiplexed imaging mass cytometry, we investigated the tumor immune microenvironment (TIME) in OSCC biopsies, characterizing immune cell distribution and signaling activity at the tumor-invasive front. Our spatial subsetting approach standardized cellular populations by tissue zone, improving feature reproducibility and revealing TIME patterns accompanying loss-of-differentiation. Employing a machine-learning pipeline combining reliable feature selection with multivariable modeling, we achieved accurate histological grade classification (AUC = 0.88). Three model features correlated with clinical outcomes in an independent cohort: granulocyte MAPKAPK2 signaling at the tumor front, stromal CD4+ memory T cell size, and the distance of fibroblasts from the tumor border. This study establishes a robust modeling framework for distilling complex imaging data, uncovering sentinel characteristics of the OSCC TIME to facilitate prognostic biomarkers discovery for recurrence risk stratification and immunomodulatory therapy development.

The SGLT2 inhibitor canagliflozin suppresses growth and enhances prostate cancer response to radiotherapy.

Radiotherapy is a non-invasive standard treatment for prostate cancer (PC). However, PC develops radio-resistance, highlighting a need for agents to improve radiotherapy response. Canagliflozin, an inhibitor of sodium-glucose co-transporter-2, is approved for use in diabetes and heart failure, but is also shown to inhibit PC growth. However, whether canagliflozin can improve radiotherapy response in PC remains unknown. Here, we show that well-tolerated doses of canagliflozin suppress proliferation and survival of androgen-sensitive and insensitive human PC cells and tumors and sensitize them to radiotherapy. Canagliflozin blocks mitochondrial respiration, promotes AMPK activity, inhibits the MAPK and mTOR-p70S6k/4EBP1 pathways, activates cell cycle checkpoints, and inhibits proliferation in part through HIF-1α suppression. Canagliflozin mediates transcriptional reprogramming of several metabolic and survival pathways known to be regulated by ETS and E2F family transcription factors. Genes downregulated by canagliflozin are associated with poor PC prognosis. This study lays the groundwork for clinical investigation of canagliflozin in PC prevention and treatment in combination with radiotherapy.

Dosimetric correlates of toxicities and quality of life following two-fraction stereotactic ablative radiotherapy (SABR) for prostate cancer.

PURPOSE: There is no evidence-based data to guide dose constraints in two-fraction prostate stereotactic ablative radiotherapy (SABR). Using individual patient-data from two prospective trials, we aimed to correlate dosimetric parameters with toxicities and quality of life (QoL) outcomes. MATERIALS AND METHODS: We included 60 patients who had two-fraction prostate SABR in the 2STAR (NCT02031328) and 2SMART (NCT03588819) trials. The prescribed dose was 26 Gy to the prostate+/-32 Gy boost to the dominant intraprostatic lesions. Toxicities and QoL data were prospectively collected using CTCAEv4 and EPIC-26 questionnaire. The outcomes evaluated were acute and late grade ≥ 2 toxicities, and late minimal clinical important changes (MCIC) in QoL domains. Dosimetric parameters for bladder, urethra, rectum, and penile bulb were evaluated. RESULTS: The median follow-up was 56 months (range: 39-78 months). The cumulative incidence of grade ≥ 2 genitourinary (GU), gastrointestinal (GI), and sexual toxicities were 62%, 3%, and 17% respectively in the acute setting (<3 months), and 57%, 15%, and 52% respectively in late setting (>6 months). There were 36%, 28%, and 29% patients who had late MCIC in urinary, bowel and sexual QoL outcomes respectively. Bladder 0.5 cc was significant predictor for late grade ≥ 2 GU toxicities, with optimal cut-off of 25.5 Gy. Penile bulb D5cc was associated of late grade ≥ 2 sexual toxicities (no optimal cut-off was identified). No dosimetric parameters were identified to be associated with other outcomes. CONCLUSION: Using real-life patient data from prospective trials with medium-term follow-up, we identified additional dose constraints that may mitigate the risk of late treatment-related toxicities for two-fraction prostate SABR.

Prostate Cancer Reshapes the Secreted and Extracellular Vesicle Urinary Proteomes.

Urine is a complex biofluid that reflects both overall physiologic state and the state of the genitourinary tissues through which it passes. It contains both secreted proteins and proteins encapsulated in tissue-derived extracellular vesicles (EVs). To understand the population variability and clinical utility of urine, we quantified the secreted and EV proteomes from 190 men, including a subset with prostate cancer. We demonstrate that a simple protocol enriches prostatic proteins in urine. Secreted and EV proteins arise from different subcellular compartments. Urinary EVs are faithful surrogates of tissue proteomes, but secreted proteins in urine or cell line EVs are not. The urinary proteome is longitudinally stable over several years. It can accurately and non-invasively distinguish malignant from benign prostatic lesions, and can risk-stratify prostate tumors. This resource quantifies the complexity of the urinary proteome, and reveals the synergistic value of secreted and EV proteomes for translational and biomarker studies.

Maxillomandibular Advancement Efficacy in Obstructive Sleep Apnea Patients With Class 2 Versus 3 Dentofacial Deformity.

OBJECTIVE: To compare the efficacy of maxillomandibular advancement (MMA) for patients with obstructive sleep apnea (OSA) with class 2 versus 3 dentofacial deformities (DFDs). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary sleep surgery center. METHODS: Patients with OSA and DFD class 2 versus 3 undergoing MMA at Stanford Sleep Surgery between 2014 and 2021 were matched by preoperative body mass index (BMI), age, and sex. Postoperative outcome was compared with polysomnography measures and patient-reported outcome measures (PROMs). RESULTS: Twenty-eight matched subjects, 14 in each deformity group were identified and assessed. The mean age (standard deviation) was 34.29 (10.21) and 33.86 (10.23) for classes 2 and 3, respectively. The apnea-hypopnea index (AHI) decreased from 43.42 (28.30) to 9.6 (5.29) (p < .001) and 37.17 (35.77) to 11.81 (15.74) (p = .042) in class 2 and 3 subjects, respectively. The oxygen desaturation index (ODI) changed from 30.48 (24.02) to 6.88 (3.39) (p = .024) and 11.43 (11.40) to 5.44 (7.96) (p = .85) in class 2 and 3 subjects, respectively. The Epworth sleepiness scale changed from 8.93 (5.28) to 3.91 (2.70) (p = .018) and 10.23 (4.38) to 4.22 (3.07) (p = .006) in class 2 and 3 subjects, respectively. CONCLUSION: Among age, sex, and BMI-matched subjects, MMA is equally effective in both dentofacial class 2 and 3 groups, both objectively and subjectively. Preoperatively, dentofacial class 2 patients with OSA presented with the more severe disease with higher AHI and ODI. Dentofacial class 3 patients with OSA may require additional attention to improve nasal function outcomes.

Native Mass Spectrometry Quantitation of α2-3-Linked N-Acetylneuraminic Acid Content of Prostate-Specific Antigen: An Accurate Liquid Biopsy for Clinically Significant Prostate Cancer.

Application of the prostate-specific antigen (PSA) test, which measures PSA levels in blood, is standard in prostate cancer (PCa) screening. However, because PSA levels may be elevated for reasons other than PCa, it leads to high rates of misdiagnosis and overtreatment. Recently, alteration in the N-glycan sialylation of PSA, specifically increased levels of α2-3-linked N-acetylneuraminic acid (α2-3-Neu5Ac or α2-3-sialic acid), was identified as a potential biomarker for clinically significant PCa. Here, we introduce a robust top-down native mass spectrometry (MS) approach, performed using a combination of α2-3-Neu5Ac-specific and nonspecific neuraminidases and employing center-of-mass monitoring (CoMMon), for quantifying the levels of α2-3-Neu5Ac as a fraction of total N-linked Neu5Ac present on PSA extracted from blood serum. To illustrate the potential of the assay for clinical diagnosis and disease staging of PCa, the percentages of α2-3-Neu5Ac on PSA (%α23PSA) in the serum of low-grade (International Society of Urological Pathology Grade Group/GG1), intermediate-grade (GG2), and high-grade (GG3,4,5) PCa individuals were measured. We observed a high sensitivity (85.5%) and specificity (84.6%) for discrimination of GG1 from clinically significant GG2-5 patients when using a %α23PSA test cut-off of 28.0%. Our results establish that the %α23PSA in blood serum PSA, which can be precisely measured in a non-invasive manner with our dual neuraminidase native MS/CoMMon assay, can discriminate between clinically significant PCa (GG2-5) and low-grade PCa (GG1). Such discrimination has not been previously achieved and represents an important clinical need. This assay could greatly improve the standard PSA test and serve as a valuable PCa diagnostic tool.

To Boost or Not to Boost: Pooled Analyses From 2-Fraction SABR Trials for Localized Prostate Cancer.

PURPOSE: Focal boost to dominant intraprostatic lesion (DIL) is an approach for dose escalation in prostate radiation therapy. In this study, we aimed to report the outcomes of 2-fraction SABR ± DIL boost. METHODS AND MATERIALS: We included 60 patients with low- to intermediate-risk prostate cancer enrolled in 2 phase 2 trials (30 patients in each trial). In the 2STAR trial (NCT02031328), 26 Gy (equivalent dose in 2-Gy fractions = 105.4 Gy) was delivered to the prostate. In the 2SMART trial (NCT03588819), 26 Gy was delivered to the prostate, with up to 32 Gy boost to magnetic resonance imaging-defined DIL (equivalent dose in 2-Gy fractions = 156.4 Gy). The reported outcomes included prostate-specific antigen (PSA) response (ie, <0.4 ng/mL) at 4 years (4yrPSARR), biochemical failure (BF), acute and late toxicities, and quality of life (QOL). RESULTS: In 2SMART, median DIL D99% of 32.3 Gy was delivered. Median follow-up was 72.7 months (range, 69.1-75.) in 2STAR and 43.6 months (range, 38.7-49.5) in 2SMART. The 4yrPSARR was 57% (17/30) in 2STAR and 63% (15/24) in 2SMART (P = 0.7). The 4-year cumulative BF was 0% in 2STAR and 8.3% in 2SMART (P = 0.1). The 6-year BF in 2STAR was 3.5%. For genitourinary toxicities, there were differences in grade ≥1 urinary urgency in the acute (0% vs 47%; P < .001) and late settings (10% vs 67%; P < .001) favoring 2STAR. For urinary QOL, no difference was observed in the acute setting, but lower proportion in 2STAR had minimal clinically important changes in urinary QOL score in the late setting (21% vs 50%; P = .03). There were no significant differences in gastrointestinal and sexual toxicities and QOL in both acute and late settings between the 2 trials. CONCLUSIONS: This study presents the first prospective data comparing 2-fraction prostate SABR ± DIL boost. The addition of DIL boost resulted in similar medium-term efficacy (in 4yrPSARR and BF), with impact on late urinary QOL outcomes.

Ultrasound-stimulated microbubbles enhanced vascular disruption in fractionated radiotherapy-treated tumours via ASMase activation.

Recent studies have indicated that radiotherapy affects tumour vasculature as well as tumour cells. The use of ultrasound-stimulated microbubbles (USMB) can potentially enhance the effects of radiotherapy through the activation of the acid sphingomyelinase [ASMase or sphingomyelin phosphodiesterase 1 (SMPD1)]-ceramide pathway. ASMase knockout (ASMase-/-) and wild-type (WT) mice bearing fibrosarcoma (MCA/129 tumour line) were treated with 10 Gy or 20 Gy in five fractions alongside or independently of USMB treatments. The results indicated that tumour responses to fractionated radiotherapy (fXRT) were enhanced when fXRT was coupled with USMB as part of the treatment regimen. Sphingosine-1-phosphate (S1P)-treated mice and ASMase-/- mice demonstrated radioresistance against fXRT alone, whereas only ASMase-/- mice showed radioresistance against fXRT treatment alone and when combined with USMB. Results indicated that in WT and S1P-treated cohorts, the use of USMB with fXRT enhanced the tumour response compared to use of USMB or fXRT alone. Although in WT and S1P-treated cohorts, there was enhanced vascular disruption, ASMase-/- cohorts demonstrated no significant vascular disruption, indicating the importance of ASMase in facilitating vascular changes in response to fXRT and USMB treatment.

Association of Backscattered Ultrasonographic Imaging of the Tongue With Severity of Obstructive Sleep Apnea in Adults.

Importance: Determining interventions to manage obstructive sleep apnea (OSA) depends on clinical examination, polysomnography (PSG) results, and imaging analysis. There remains the need of a noninvasive and cost-effective way to correlate relevant upper airway anatomy with severity of OSA to direct treatment and optimize outcome. Objective: To determine whether backscattered ultrasonographic imaging (BUI) analysis of the tongue is associated with severity of OSA in adults. Design, Setting, and Participants: In this prospective, single-center, diagnostic study of a consecutive series of patients (aged ≥18 years) at a sleep surgery clinic, the 89 included patients had a PSG within 3 years at the time of ultrasonography and BUI analysis between July 2020 and March 2022. Patients were excluded if body mass index had changed more than 10% since time of PSG. A standardized submental ultrasonographic scan with laser alignment was used with B-mode and BUI analysis applied to the tongue. The B-mode and BUI intensity were associated with the apnea-hypopnea index (AHI), a measure of severity of apnea from normal (no OSA) to severe OSA. Exposures: Ultrasonography and PSG. Main Outcomes and Measures: The main outcomes were BUI parameters and their association with AHI value. Results: Eighty-nine patients were included between July 2020 and March 2022. A total of 70 (78.7%) male patients were included; and distribution by race and ethnicity was 46 (52%) White participants, 22 (25%) Asian participants, and 2 (2%) African American participants, and 19 (21%) others. Median (IQR) age was 37.0 (29.0-48.3) years; median (IQR) BMI was 25.3 (23.2-29.8); and median (IQR) AHI was 11.1 (5.6-23.1) events per hour. At the middle to posterior tongue region, the 4 OSA severity levels explained a significant portion of the BUI variance (η2 = 0.153-0.236), and a significant difference in BUI values was found between the subgroups with AHI values of less than 15 (no OSA and mild OSA) and greater than or equal to 15 (moderate OSA and severe OSA) events per hour. The echo intensity showed no significant differences. The BUI values showed a positive association with AHI, with a Spearman correlation coefficient of up to 0.43. Higher BUI values remained associated with higher AHI after correction for the covariates of BMI and age. Conclusions and Relevance: In this prospective diagnostic study, standardized BUI analysis of the tongue was associated with OSA severity. With the practicality of ultrasonography, this analysis is pivotal in connecting anatomy with physiology in treatment planning for patients with OSA.

A roadmap of craniofacial growth modification for children with sleep-disordered breathing: a multidisciplinary proposal.

Craniofacial modification by orthodontic techniques is increasingly incorporated into the multidisciplinary management of sleep-disordered breathing in children and adolescents. With increasing application of orthodontics to this clinical population it is important for healthcare providers, families, and patients to understand the wide range of available treatments. Orthodontists can guide craniofacial growth depending on age; therefore, it is important to work with other providers for a team-based approach to sleep-disordered breathing. From infancy to adulthood the dentition and craniofacial complex change with growth patterns that can be intercepted and targeted at critical time points. This article proposes a clinical guideline for application of multidisciplinary care with emphasis on dentofacial interventions that target variable growth patterns. We also highlight how these guidelines serve as a roadmap for the key questions that will influence future research directions. Ultimately the appropriate application of these orthodontic techniques will not only provide an important therapeutic option for children and adolescents with symptomatic sleep-disordered breathing but may help also mitigate or prevent its onset.

Changes in tongue morphology predict responses in pharyngeal patency to selective hypoglossal nerve stimulation.

STUDY OBJECTIVES: The major goal of the study was to determine whether changes in tongue morphology under selective hypoglossal nerve therapy for obstructive sleep apnea were associated with alterations in airway patency during sleep when specific portions of the hypoglossal nerve were stimulated. METHODS: This case series was conducted at the Johns Hopkins Sleep Disorders Center at Johns Hopkins Bayview Medical Center. Twelve patients with apnea implanted with a multichannel targeted hypoglossal nerve-stimulating system underwent midsagittal ultrasound tongue imaging during wakefulness. Changes in tongue shape were characterized by measuring the vertical height and polar dimensions between tongue surface and genioglossi origin in the mandible. Changes in patency were characterized by comparing airflow responses between stimulated and adjacent unstimulated breaths during non-rapid eye movement sleep. RESULTS: Two distinct morphologic responses were observed. Anterior tongue base and hyoid-bone movement (5.4 [0.4] to 4.1 [1.0] cm (median and [interquartile range]) with concomitant increases in tongue height (5.0 [0.9] to 5.6 [0.7] cm) were associated with decreases in airflow during stimulation. In contrast, comparable anterior hyoid movement (tongue protrusion from 5.8 [0.5] to 4.5 [0.9] cm) without significant increases in height (5.2 [1.6] to 4.6 [0.8] cm) were associated with marked increases in airflow during sleep. CONCLUSIONS: Tongue protrusion with preservation of tongue shape predicted increases in patency, whereas anterior movement with concomitant increases in height were associated with decreased pharyngeal patency. These findings suggest that pharyngeal patency can be best stabilized by stimulating lingual muscles that maintain tongue shape while protruding the tongue, thereby preventing it from prolapsing posteriorly during sleep. CITATION: Fleury Curado T, Pham L, Otvos T, et al. Changes in tongue morphology predict responses in pharyngeal patency to selective hypoglossal nerve stimulation. J Clin Sleep Med. 2023;19(5):947-955.

Nanotechnology and machine learning enable circulating tumor cells as a reliable biomarker for radiotherapy responses of gastrointestinal cancer patients.

A highly sensitive, circulating tumor cell (CTC)-based liquid biopsy was used to monitor gastrointestinal cancer patients during treatment to determine if CTC abundance was predictive of disease recurrence. The approach used a combination of biomimetic cell rolling on recombinant E-selectin and dendrimer-mediated multivalent immunocapture at the nanoscale to purify CTCs from peripheral blood mononuclear cells. Due to the exceptionally high numbers of CTCs captured, a machine learning algorithm approach was developed to efficiently and reliably quantify abundance of immunocytochemically-labeled cells. A convolutional neural network and logistic regression model achieved 82.9% true-positive identification of CTCs with a false positive rate below 0.1% on a validation set. The approach was then used to quantify CTC abundance in peripheral blood samples from 27 subjects before, during, and following treatments. Samples drawn from the patients either prior to receiving radiotherapy or early in chemotherapy had a median 50 CTC ml-1 whole blood (range 0.6-541.6). We found that the CTC counts drawn 3 months post treatment were predictive of disease progression (p = .045). This approach to quantifying CTC abundance may be a clinically impactful in the timely determination of gastrointestinal cancer progression or response to treatment.