[Whole view of the immune microenvironment of biliary tract cancer]

Biliary tract cancer is a group of malignancies which originate from biliary epithelium, and adenocarcinoma is the main pathological type. Although surgical resection is the only radical treatment strategy, most biliary tract cancer patients are diagnosed at locally advanced stage or with distant metastasis. Biliary tract cancer is highly resistant to the conventional chemoradiotherapy and the emerging immunotherapy including immune checkpoint inhibitors, owing to the suppressive immune microenvironment. In a whole view, this paper discussed the anti-tumor and tumor-promoting immune responses of the various immune cells and stromal cells in the immune microenvironment of biliary tract cancer, as well as their correlation with prognosis. The understanding of the whole view of immune microenvironment in biliary tract cancer patients could further inform the design of clinical trials of immunotherapy or combination therapy.

Identification of novel characteristic biomarkers and immune infiltration profile for the anaplastic thyroid cancer via machine learning algorithms

PURPOSE

Anaplastic thyroid cancer (ATC) is a rare and lethal malignant cancer. In recent years, the application of molecular-driven targeted therapy and immunotherapy has markedly improved the prognosis of ATC. This study aimed to identify characteristic genes for ATC diagnosis and revealed the role of ATC characteristic genes in drug sensitivity and immune cell infiltration.

METHODS

We downloaded ATC RNA-sequencing data from the GEO database. Following the combination and normalization of the dataset, we first divided the combined datasets into the training cohort and the validation cohort. We identified differentially expressed genes (DEGs) in ATC by differential expression analysis in the training cohort. We used two machine learning algorithms, least absolute shrinkage and selection operator (LASSO) and support vector machine-recursive feature elimination (SVM-RFE) to identify ATC characteristic genes. The CIBERSORT algorithm was performed to calculate the abundance of various immune cells in ATC. Finally, we validated the expression of ATC characteristic genes by quantitative RT-PCR (RT-qPCR) in ATC cell lines and immunohistochemistry (IHC).

RESULTS

A total of 425 DEGs were identified in the training cohort, including 240 upregulated genes and 185 downregulated genes. Four ATC characteristic genes (ADM, PXDN, MMP1, and TFF3) were identified, and their diagnostic value was validated in the validation cohort (AUC in ROC analysis > 0.75). We established a practical gene expression-based nomogram to accurately predict the probability of ATC. We also found that ATC characteristic biomarkers are associated with the tumor immune microenvironment and drug sensitivity.

CONCLUSION

ADM, PXDN, MMP1, and TFF3 might serve as potential ATC diagnostic biomarkers and may be helpful for ATC molecular targeted therapy and immunotherapy.

Short- and long-term outcomes of laparoscopic versus open pelvic exenteration for locally advanced rectal cancer: a single-center propensity score matching analysis

BACKGROUND

Research on short-term outcomes and long-term oncological results of laparoscopic pelvic exenteration (LPE) for locally advanced rectal cancer (LARC) is still limited. The purpose of this study was to compare the outcomes of LPE and open pelvic exenteration (OPE).

METHODS

Between January 2010 and December 2019, consecutive LARC patients who underwent radical pelvic exenteration at Peking University First Hospital were enrolled. Groups were matched at a 1:1 ratio using propensity score matching. The primary endpoints were 3 year overall survival (OS) and disease-free survival (DFS). The secondary endpoints were postoperative short-term outcomes.

RESULTS

There were 144 patients (68 males and 76 females, median age 58.5 [range 27.0-86.0] years). After matching, patients were stratified into LPE (n = 48) and OPE (n = 48) groups (LPE: 24 males and 24 females, median age 57.0 [range 27.0-81.0] years; OPE: 26 males and 22 females, median age 58.0[range 36.0-80.0] years). There were no significant differences on baseline data between the two groups. Compared with the OPE group, the LPE group had a significantly lower estimated blood loss (200 vs 500 ml, p = 0.003), less overall postoperative complications (12/48 vs 25/48, p = 0.006), less surgical site infection (8/48 vs 20/48, p = 0.007), shorter length of stay (12 vs. 15 days, p = 0.005), but similar operative time (344 vs. 360 min, p = 0.493). The pathological R0 resection rate (98.0% vs. 93.7%, p = 0.610), 3 year local recurrence (18.4% vs. 23.5, p = 0.140), 3 year OS (74.6% vs. 65.5%, p = 0.290) and 3-year DFS (60.0% vs. 50.3%, p = 0.208) were similar between the two groups. Shorter distance from anal verge (HR = 0.92, p = 0.042), (y) pT4b (HR = 2.45, p = 0.023), (y)pN1-2 (HR = 2.42, p = 0.004) and positive CRM (HR = 6.23, p = 0.004) were independent prognostic risks for 3 year DFS.

CONCLUSIONS

LPE can be performed safely and has certain short-term advantages over OPE, most notably less blood loss and surgical site infection. However, LPE does not improve long-term oncological outcomes.

Recent RhIG Administration Does Not Interfere with the Rosette Test

Introduction/Objective

Administration of Rh immune globulin (RhIG) is indicated mid-gestation (28 weeks) and after delivery to prevent Rh D sensitization in Rh D negative women. Women with sporadic prenatal care may not receive the first dose at 28 weeks, and may end up receiving their first dose closer to delivery. The rosette test (RT) is a rapid screen for fetomaternal hemorrhage (FMH) that uses an IgM anti-D antibody to detect fetal Rh D positive red blood cells (RBC) in maternal circulation. It is not currently known if or how recent administration of RhIG prior to performance of a RT may interfere with RBC agglutination and test results.

Methods/Case Report

To approximate mixing of fetal Rh D positive RBC with maternal Rh D negative RBC during FMH, 2% volume of Rh D positive RBC from fetal cord and adult donor samples were spiked into Rh D negative RBC. These mixtures were then incubated with a physiologic concentration of RhIG to occupy all Rh D antigen sites on the Rh D positive cells prior to performing the RT.

Results (if a Case Study enter NA)

Addition of Rh D positive RBC and RhIG to Rh D negative RBC did not affect rosette formation. Rh D negative cells had 0 rosettes/LPF. Rh D negative cells spiked with 2% Rh D positive adult donor and fetal cord RBC by volume produced an average of 9.8 rosettes/LPF (SD: 2.8) and 11.2 (SD: 3.3), respectively. Addition of a physiologic concentration of RhIG to the spiked Rh D positive adult donor and fetal cord RBC produced an average of 13.0 rosettes/LPF (SD: 2.5) and 11.2 rosettes/LPF (SD: 2.6), respectively.

Conclusion

Incubation of Rh D positive RBCs with physiologic concentration of RhIG does not affect the rosette test. Clinicians and laboratorians should be reassured that the rosette test continues to be an accurate way to quantitate FMH after recent RhIG administration.

Combining tau-PET and fMRI meta-analyses for patient-centered prediction of cognitive decline in Alzheimer’s disease

Background

Tau-PET is a prognostic marker for cognitive decline in Alzheimer’s disease, and the heterogeneity of tau-PET patterns matches cognitive symptom heterogeneity. Thus, tau-PET may allow precision-medicine prediction of individual tau-related cognitive trajectories, which can be important for determining patient-specific cognitive endpoints in clinical trials. Here, we aimed to examine whether tau-PET in cognitive-domain-specific brain regions, identified via fMRI meta-analyses, allows the prediction of domain-specific cognitive decline. Further, we aimed to determine whether tau-PET-informed personalized cognitive composites capture patient-specific cognitive trajectories more sensitively than conventional cognitive measures.

Methods

We included Alzheimer’s Disease Neuroimaging Initiative (ADNI) participants classified as controls (i.e., amyloid-negative, cognitively normal, n = 121) or Alzheimer’s disease-spectrum (i.e., amyloid-positive, cognitively normal to dementia, n = 140), plus 111 AVID-1451-A05 participants for independent validation (controls/Alzheimer’s disease-spectrum=46/65). All participants underwent baseline ¹⁸F-flortaucipir tau-PET, amyloid-PET, and longitudinal cognitive testing to assess annual cognitive changes (i.e., episodic memory, language, executive functioning, visuospatial). Cognitive changes were calculated using linear mixed models. Independent meta-analytical task-fMRI activation maps for each included cognitive domain were obtained from the Neurosynth database and applied to tau-PET to determine tau-PET signal in cognitive-domain-specific brain regions. In bootstrapped linear regression, we assessed the strength of the relationship (i.e., partial R²) between cognitive-domain-specific tau-PET vs. global or temporal-lobe tau-PET and cognitive changes. Further, we used tau-PET-based prediction of domain-specific decline to compose personalized cognitive composites that were tailored to capture patient-specific cognitive decline.

Results

In both amyloid-positive cohorts (ADNI [age = 75.99±7.69] and A05 [age = 74.03±9.03]), cognitive-domain-specific tau-PET outperformed global and temporal-lobe tau-PET for predicting future cognitive decline in episodic memory, language, executive functioning, and visuospatial abilities. Further, a tau-PET-informed personalized cognitive composite across cognitive domains enhanced the sensitivity to assess cognitive decline in amyloid-positive subjects, yielding lower sample sizes required for detecting simulated intervention effects compared to conventional cognitive endpoints (i.e., memory composite, global cognitive composite). However, the latter effect was less strong in A05 compared to the ADNI cohort.

Conclusion

Combining tau-PET with task-fMRI-derived maps of major cognitive domains facilitates the prediction of domain-specific cognitive decline. This approach may help to increase the sensitivity to detect Alzheimer’s disease-related cognitive decline and to determine personalized cognitive endpoints in clinical trials.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-022-01105-5.

A closed-loop recycling process for carbon fiber-reinforced polymer waste using thermally activated oxide semiconductors: Carbon fiber recycling, characterization and life cycle assessment

The objective of this study is to investigate the properties of recycled carbon fiber (rCF) and its environmental impact, with a specific focus on the energy consumption of the recycling process based on the use of thermally activated oxide semiconductors (TASC). The mechanical and surface properties of rCF obtained under the optimal process parameters were characterized. The life cycle assessment method was used to evaluate the environmental impact of a closed-loop recycling process for carbon fiber-reinforced polymer (CFRP) waste using TASC. The results indicated that the decomposition rate of resin was 95.5 %, and no carbonaceous solid was generated. The gaseous produced of the recycling process were mainly CO₂ and H₂O, and no liquid products were produced. The surface oxidation degree of rCF was relatively slight. COOH was generated on the surface of rCF, which was conducive to improving the interfacial adhesion viscosity with resin. The monofilament tensile strength of rCF was maintained above 97 %. Compared with landfill and incineration, CFRP waste recycling using TASC can make global warming potential, acidification potential and eutrophication potential reduced by 28 %, 32 %, and 25 %, respectively. Ozone layer depletion potential, human toxicity potential and terrestrial ecotoxicity potential in disposing CFRP waste using TASC were 30 %, 21 % and 41 % of that using pyrolysis, respectively. The energy consumption in carbon fiber recycling by TASC was only 23 % of that in virgin carbon fiber manufacturing. TASC is found to be a promising potential strategy for managing CFRP waste.

Blood pressure and clinical outcomes in patients with diabetes and stable coronary artery disease in THEMIS

Background

Various BP characteristics, e.g., systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse pressure (PP), as well as heart rate (HR) may affect the risk of both cardiovascular events and bleeding events. However, the exact way in which these characteristics and outcomes are associated among patients with diabetes and stable coronary artery disease (CAD) remains debated. Moreover, it is unknown whether the risks and benefits of intensified antiplatelet therapy in this patient population are affected by their baseline BP and HR.

Purpose

To assess the relationship between BP components (including HR) and cardiovascular and bleeding events, and to determine if the effects of ticagrelor vs. placebo varied across the BP and HR spectrum, in patients with diabetes and stable CAD.

Methods

THEMIS was a randomized, controlled trial in which 19,220 individuals ≥50 years of age with stable CAD and type 2 diabetes were randomized to receive either ticagrelor plus aspirin or placebo plus aspirin. Patients with a prior myocardial infarction or stroke, or already on dual antiplatelet therapy, were excluded. The primary efficacy outcome was a composite of cardiovascular death, myocardial infarction, or stroke. The primary safety outcome was TIMI major bleeding. We examined prognostic implications of BP components using 1) restricted cubic splines for the overall trends with outcomes; 2) Cox proportional-hazards regression models with predefined BP component intervals adjusted for demographic, clinical, and laboratory variables; and 3) Cox regression models for the effects of ticagrelor vs. placebo on outcomes across the spectrum of BP component values (test for interaction). THEMIS is registered at ClinicalTrials.gov (NCT01991795).

Results

Mean values of baseline BP components were similar between the two study groups. Median follow-up duration was 39.9 months (range 0–57), with 1554 primary efficacy events and 306 primary safety events occurring over the course of the study. All BP components (including HR) displayed various, independent relationships with the tested outcomes. For example, in adjusted spline models, SBP displayed non-linear relationships with the primary outcome, all-cause death, any bleeding, serious adverse events, and intracranial bleeding, and linear relationships with the remaining outcomes. Figure 1 shows the associations of each BP component with the primary efficacy outcome. BP components did not substantially modify the risks and benefits of ticagrelor vs. placebo for the tested outcomes.

Conclusions

BP components were independently associated with efficacy and safety outcomes in patients with stable CAD and type 2 diabetes. However, no important modification of BP components on the effect of ticagrelor vs. placebo was detected.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): AstraZeneca

Serum microRNA miR-491-5p/miR-206 Is Correlated with Poor Outcomes/Spontaneous Hemorrhagic Transformation after Ischemic Stroke: A Case Control Study

Background: It is unclear whether miR-491-5p, miR-206, miR-21-5p or miR-3123 are associated with functional outcomes and hemorrhagic transformation (HT) after acute ischemic stroke (AIS). In this study, we aimed to investigate the correlation between these four microRNAs and functional outcomes, as well as spontaneous HT after AIS; Methods: We included 215 AIS patients and retrospectively assayed for miR-21-5p, miR-206, miR-3123 and miR-491-5p levels in serum. Poor functional outcome was defined as a modified Rankin Scale score ≥ 3. Spontaneous HT referred to hemorrhage detected in follow-up brain imaging but not on admission, without reperfusion therapies. Logistic regression, generalized additive model and 2-piecewise regression model were used to explore the independent, non-linear correlation between miRNA expression levels and outcomes; Results: We included 215 AIS patients. Higher miR-491-5p level independently reduced the risk of poor functional outcomes at 1 year (OR 0.90, 95% CI 0.82–0.98, corrected p value = 0.044). Higher miR-206 level significantly increased the risk of spontaneous HT (OR 1.64, 95% CI 1.17–2.30, corrected p value = 0.016). There was a nonlinear correlation found between miR-491-5p level and 1 year outcome with an inflection point of 2.180, while an approximately linear correlation was observed with an inflection point of 2.037 between miR-206 level and spontaneous HT; Conclusions: Higher serum miR-491-5p level independently reduced risk of 1-year poor functional outcome of AIS patients. Higher serum miR-206 level independently increased the risk of spontaneous HT in AIS patients. These two miRNAs may be as the potential biomarkers for improving prognosis after AIS.

Efficacy and Safety of Reirradiation with Stereotactic Body Radiation Therapy for Locally Recurrent Pancreatic Adenocarcinoma

AIMS

The purpose of this study was to report on outcomes of a cohort of patients who were treated with reirradiation with stereotactic body radiation therapy (SBRT) for locally recurrent pancreatic adenocarcinoma.

MATERIALS AND METHODS

Patients treated with SBRT reirradiation for locally recurrent pancreatic adenocarcinoma from December 2009 to April 2020 were included in the study. Descriptive statistics were used to record patient demographics, tumour and treatment characteristics. Kaplan-Meier analysis was used to evaluate overall survival, local progression-free survival (LPFS), distant metastasis-free survival and progression-free survival (PFS).

RESULTS

In total, 27 patients were included in the study. The median follow-up time from local recurrence was 19.7 months (range 4.2-43.1 months). Most patients received five-fraction SBRT (26/27, 96%). The median overall survival after local recurrence treatment was 18.3 months (range 3.0-42.6 months), with 6-month, 1-year and 2-year overall survival rates of 88.5%, 73.1% and 33.6%. The median LPFS after local recurrence treatment was 16.2 months (range 2.3-33.6 months), with 6-month, 1-year and 2-year LPFS rates of 95.8%, 62.9% and 27.2%. Peri-SBRT chemotherapy improved LPFS (median 17.5 versus 8.5 months; P = 0.010) and overall survival (median 19.3 versus 5.5 months; P = 0.049). Tumours ≤ 3 cm in the greatest dimension showed better local control (median LPFS 19.2 versus 10.2 months; P = 0.130). There was one case (4%) of acute grade 3 pain and one case (4%) of late grade 3 gastrointestinal toxicity.

CONCLUSIONS

Reirradiation with five-fraction SBRT is safe, but local control remains suboptimal. Patients with smaller tumours experienced improved outcomes, as did patients whose treatment plan included the administration of peri-SBRT chemotherapy.

[Efficacy and prognostic analysis of 125I brathytherapy combined with chemotherapy for pediatric parameningeal rhabdomyosarcoma]

Objective: To analyze the efficacy and prognostic factors in children with parameningeal rhabdomyosarcoma (PMRMS) treated by ¹²⁵I brachytherapy combined with chemotherapy. Methods: A retrospective analysis of the clinical data of 33 pediatric patients treated with ¹²⁵I brachytherapy combined with chemotherapy in Peking University Stomatological Hospital from July 2013 to October 2018 was carried out to analyze the efficacy and prognostic factors. Results: Among the 33 patients, 19 were males and 14 were females; the median age was 4 years old (1-12 years old). There were 17 cases with embryonic type, 9 cases with alveolar type, and 7 with undifferentiated type; 26 cases with original PMRMS, and 7 cases with recurrent PMRMS. The tumors occurred in subtemporal-mastoid area in 15 patients, while nasopalatine-paranasal area in 6 cases, and parapharyngeal-submandibular area in 12 cases. There were 28 patients in IRS Ⅲ, and 5 patients in IRS Ⅳ. As for the risk level, 28 cases were in the middle-risk group and 5 cases in the high-risk group. The median follow-up time was 52 months. The 1, 3, and 5-year local control rates were 87.9%, 58.6%, and 49.9%, and the 1, 3, and 5-year survival rates were 93.8%, 60.5%, and 47.5%, respectively. The 5-year local control rate and 5-year survival rate of 12 patients with the tumor in the parapharyngeal-submandibular area were 91.7% and 100%, respectively. The 5-year local control rate and 5-year survival rate of the 6 patients with tumor in the nasopalatine-paranasal area were both 83.3%. The 3-year local control rate and 3-year survival rate of the 15 patients with tumor in the subtemporal-mastoid area were 17.5% and 21.4%. The multivariate survival analysis using Cox proportional risk regression model showed that the tumor located in the subtemporal-mastoid area was an independent risk factor affecting the 5-year overall survival rate (HR=38.40, 95%CI: 4.87-302.52, P=0.001). Within 3 months after ¹²⁵I seed implantation, the incidence of acute radiotherapy adverse reactions in all patients was 84.8% (28/33). Twenty-one patients (63.6%) had a grade 1 acute radiotherapy reaction, and 7 cases (21.2%) had a grade 2 acute radiotherapy reaction. No acute radiotherapy adverse reactions of grade 3 or 4 occurred. Three months after ¹²⁵I seed implantation, the adverse reactions were significantly alleviated, and no adverse reactions of grade 3 or above such as skin ulcer or salivary gland fibrosis occurred, and no serious cranio-maxillofacial deformities occurred. Conclusions: ¹²⁵I seed brachytherapy combined with chemotherapy has a definite clinical effect in the treatment of children with parameningeal rhabdomyosarcoma. The prognosis of rhabdomyosarcoma in the parapharyngeal-submandibular area and nasopalatine-paranasal area is better than that in the subtemporal-mastoid area.

Finger touching combined X-ray-guided percutaneous nephrolithotomy in 640 cases: an 8-years' experience

OBJECTIVE

We aimed to evaluate the safety and efficacy of finger touching combined X-ray-guided percutaneous nephrolithotomy, and the feasibility of avoiding damage in medical staff caused by X-ray.

PATIENTS AND METHODS

From January 2013 to December 2020, 640 cases of percutaneous nephrolithotomy were performed through the 18-24-F channel. Among those cases, 22 (3.4%) cases were double-sided kidney stones surgeries, 294 (45.8%) cases were on the right side and 324 (50.5%) cases were on the left side. The targeted renal calyceal puncture was carried out under the combined guidance of the doctor's finger and X-ray. We assessed the X-ray exposure time of patients and doctors, average number of punctures, postoperative hospitalization, calculus removal rates, and complications.

RESULTS

The average number of punctures was 2.8 ± 1.4. Average X-ray exposure time during procedure: 2.8 s (range: 2-8 s). Average surgical time: 106.5 ± 49.4 min. Postoperative hospitalization: 6.8 ± 4.2 d. Average reduced hemoglobin level: 5.9 g/day. Stone-free rate 4 weeks after surgeries: 95.6%. Patients with upper ureteral calculi: 395 cases (61.72%). The calculus residual rate of patients with staghorn renal calculi or multiple renal calculi complementary treatments was 82.9%, including 0 patients who received shock wave lithotripsy, 2 cases of repeated percutaneous nephrolithotomy (PCNL), and 18 cases of ureteroscopy. Postoperative placement of renal drainage tube occurred in 52 cases. As for complications, no perirenal infection occurred, two severe bleeding complication cases occurred, and one case of colon perforation occurred.

CONCLUSIONS

Finger touching combined X-ray-guided percutaneous nephrolithotomy in patients with renal calculus is safe and can accurately guide the puncture without radiation hazards. The placement of a renal drainage tube was beneficial to reduce renal effusion, hematocele, and infections.

A turn-on NIR fluorescence sensor for gossypol based on Yb-based metal-organic framework

The development of analytical method for selective and sensitive detection of gossypol (Gsp), an extraction from the cotton plants, is important but still challenging in food safety and medical field. Herein, we reported a turn-on near infrared (NIR) fluorescence detection strategy for Gsp based on a metal-organic framework (MOF), QBA-Yb, which was prepared from 4,4'-(quinolone-5, 8-diyl) benzoate with Yb(NO₃)₃·5H₂O by solvothermal synthesis. The Gsp acted as another "antenna" to sensitize the luminescence of Yb³⁺, leading to the turn-on NIR emission upon 467 nm excitation. As Gsp concentration increased, the NIR emission at 973 nm enhanced gradually, thus enabling highly sensitive Gsp detection in a turn-on way. The experiment and theoretical calculation results revealed the presence of strong hydrogen bonds between Gsp molecules and the MOF skeleton. The developed QBA-Yb probe showed excellent characteristics for detection of Gsp molecules, accompanied by wide linear range (5-160 μg/mL), low detection limit (0.65 μg/mL) and short response time (within 10 min). We have further demonstrated that the QBA-Yb probe was successfully applied for the determination of Gsp in real samples of cottonseeds.

Gene expression in Lucilia sericata (Diptera: Calliphoridae) larvae exposed to Pseudomonas aeruginosa and Acinetobacter baumannii identifies shared and microbe-specific induction of immune genes

Antibiotic resistance is a continuing challenge in medicine. There are various strategies for expanding antibiotic therapeutic repertoires, including the use of blow flies. Their larvae exhibit strong antibiotic and antibiofilm properties that alter microbiome communities. One species, Lucilia sericata, is used to treat problematic wounds due to its debridement capabilities and its excretions and secretions that kill some pathogenic bacteria. There is much to be learned about how L. sericata interacts with microbiomes at the molecular level. To address this deficiency, gene expression was assessed after feeding exposure (1 h or 4 h) to two clinically problematic pathogens: Pseudomonas aeruginosa and Acinetobacter baumannii. The results identified immunity-related genes that were differentially expressed when exposed to these pathogens, as well as non-immune genes possibly involved in gut responses to bacterial infection. There was a greater response to P. aeruginosa that increased over time, while few genes responded to A. baumannii exposure, and expression was not time-dependent. The response to feeding on pathogens indicates a few common responses and features distinct to each pathogen, which is useful in improving the wound debridement therapy and helps to develop biomimetic alternatives.

Utilizing phenotypic characteristics of metastatic brain tumors to improve the probability of detecting circulating tumor DNA from cerebrospinal fluid in non-small-cell lung cancer patients: development and validation of a prediction model in a prospective cohort study

Background

Circulating tumor DNA (ctDNA) in cerebrospinal fluid (CSF) has become a promising surrogate for genomic profiling of central nervous system tumors. However, suboptimal ctDNA detection rates from CSF limit its clinical utility. Thus precise screening of suitable patients is needed to maximize the clinical benefit.

Patients and methods

Between February 2017 and December 2020, 66 newly diagnosed non-small-cell lung cancer (NSCLC) patients with brain parenchymal metastases were prospectively enrolled as a training cohort and 30 additional patients were enrolled as an external validation cohort. CSF samples and matched primary tumor tissues were collected before treatment and subjected to next-generation sequencing (NGS). The imageological characteristics of patients’ brain tumors were evaluated by radiologists using enhanced magnetic resonance imaging images. The clinical and imageological characteristics were evaluated by complete subsets regression, Akaike information criteria, and Bayesian information criteria methods to establish the prediction model. A nomogram was then built for CSF ctDNA detection prediction.

Results

The somatic mutation detection rate of genes covered by our targeted NGS panel was significantly lower in CSF ctDNA (59.09%) than tumor tissue (91.84%). The T_size (diameter of the largest intracranial lesion) and LVD_min (minimum lesion–ventricle distance for all intracranial lesions) were significantly associated with positive CSF ctDNA detection, and thus, were selected to establish the prediction model, which achieved an area under the ROC curve (AUC) of 0.819 and an accuracy of 0.800. The model’s predictive ability was further validated in the independent external cohort (AUC of 0.772, accuracy of 0.767) and by internal cross-validation. The CSF ctDNA detection rate was significantly improved from 58.18% (32/55) to 81.81% (27/33) in patients after model selection (P = 0.022).

Conclusions

This study developed a regression model to predict the probability of detecting CSF ctDNA using the phenotypic characteristics of metastatic brain lesions in NSCLC patients, thus, maximizing the benefits of CSF liquid biopsies.

•

Intracranial tumor size and distance to nearest ventricle were significantly correlated with positive CSF ctDNA detection.

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A prediction model incorporating T_size and LVD_min was developed and validated to evaluate the odds of CSF ctDNA positivity.

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The CSF ctDNA detection rate was significantly improved in patients after model selection.