Keywords: Cancer, CEST & MT

Motivation: Tumor budding (TB) is an important additional prognostic factor for patients with colorectal cancer (CRC).

Goal(s):  Accurate TB assessment before surgery can help guide clinical decisions and improve patient prognosis.

Approach: This study explored the feasibility of amide proton transfer-weighted (APTw) MR imaging in assessing TB grade in patients with rectal cancer (RC).

Results: We found that RC lesions with high-grade TB had higher APTw 90^th percentile values than low-grade TB.

Impact: APTw MRI may be beneficial for implementing more accurate personalized treatment and improving tumor prognosis.

Keywords: Cancer, Elastography, Liver, microvascular invasion, biomechanics

Motivation: In hepatocellular carcinoma (HCC), microvascular invasion (MVI), an indicator for tumor aggressiveness, is identified typically through post-resection pathology examination. Currently, non-invasive methods for assessing tumor aggressiveness are lacking. 

Goal(s): Our objective is to discover a non-invasive imaging biomarker for evaluating the presence/absence of MVI.

Approach: The alterations induced by the tumor, such as MVI, can modify the tissue architecture and, consequently, its mechanical properties. Magnetic resonance elastography at 40Hz was performed in 44 HCC patients who had liver resection.

Results: Peritumoral tissue phase angle accurately distinguish patients with/without MVI, indicative for aggressiveness. These results correlate with higher tumor differentiation in patients without MVI.

Impact: This clinical study introduces the phase angle as a new biomarker for gauging HCC aggressiveness whereby enabling patient stratification.

Keywords: Cancer, Cancer

Motivation: Distinct histopathological types are closely related to the prognosis of advanced gastric cancer. Adverse histopathological status (AHS) is linked to poor gastric cancer outcomes. Extra-dimensional volumetric interpolated breath-hold examination (XD-VIBE) offers high temporal and spatial resolution while allowing free breathing.

Goal(s): To improve the assessment of AHS, we explored the potential for XD-VIBE to improve DCE imaging. 

Approach: We evaluated the associations of quantitative DCE MRI parameters (e.g., Ktrans, Ve, and Kep) with AHS. 

Results: Using XD-VIBE, quantitative DCE MRI parameters allowed non-invasive assessment of AHS and helped to optimize treatment strategies for advanced gastric cancer.

Impact: In this single-institution study, quantitative DCE MRI features demonstrated promise as markers of AHS in advanced gastric cancer. These features could provide added prognostic value and identify patients who may benefit from adjuvant therapy.

Keywords: Digestive, Cancer

Motivation: Orthogonal axial images (OAI), which may improve staging performance, had been ignored in previous studies about gastric cancer (GC) T-staging using MRI.

Goal(s): To assess the value of MR OAI in GC preoperative T-staging.

Approach: Diagnostic performance metrics, over- and understaging fractions, overall accuracy (compared by McNemar test) for MRI lacking or incorporating OAI and MDCT were quantified referring to pathological T-stage.

Results: The overall accuracy was significantly higher for MRI with OAI than those without OAI, while marginally better than MDCT. Both MRI with OAI and MDCT exhibited superior staging performance than MRI without OAI.

Impact: By incorporating orthogonal axis images, MRI exhibited diagnostic performance marginally better than MDCT in preoperative T-staging of gastric cancer, thereby offering a superior, non-invasive and radiation-free protocol to determine prognosis and guide appropriate treatment strategies.

Keywords: Treatment Response, Cancer

Motivation: Neoadjuvant immunotherapy (nIT) combined with standard chemotherapy is the innovative treatment for esophageal squamous cell carcinoma (ESCC). Some patients may not respond to nIT.

Goal(s): To investigate the value of DWI-derived parameters for the assessment of pathologic response and detection of minimal residual cancer cell (MRC) to nIT.

Approach: The patient population was a sub-cohort from the clinical trial (ClinicalTrials.gov ID: NCT02611700). The pathological response evaluation according to the TRG system proposed by AJCC. DWI-derived parameters including ADC, D, D* and f.

Results: ΔADC and ΔD values were highlighting in assessment of pathologic response and detection of MRC to nIT.

Impact: Nowadays, evaluation of the response to neoadjuvant therapy for cancer mainly relies on the measurement of tumor size according to RECIST. Pseudo-progression with immunotherapy is often observed.  fMRI techniques can quantify therapy-induced changes before anatomic variation in tumor size.

Keywords: Cancer, Data Analysis

Motivation: Accurate prediction of disease-free survival (DFS) of rectal cancer patients has substantial influences on treatment planning.

Goal(s): To explore the value of ADC and T2W images in predicting DFS for rectal cancer patients.

Approach: Radiomics models using features extracted from ADC and T2W were built and evaluated.

Results: Models built with ADC features and clinical variables achieved C-Index values of 0.675 and 0.768 over the internal and external test cohorts, respectively. Models built with T2W features and clinical variables achieved C-Index values of 0.724 and 0.747 over the internal and external test cohorts, respectively.

Impact: Both the shape features extracted from ADC maps and the first-order features extracted from T2W images demonstrated strong predictive power for DFS estimation, implying the potential of combination anatomical images with diffusion models to predict DFS in rectal cancer patients.

Keywords: Cancer, CEST & MT, Rectal Adenocarcinoma, APT, prognosis

Motivation: Improving the accuracy of imaging to assess prognostic factors in rectal adenocarcinoma.

Goal(s): Recognizing early rectal adenocarcinoma, assisting clinicians to achieve precision treatment.

Approach: Prospective enrollment of rectal adenocarcinoma patients without neoadjuvant therapy undergoing radical surgery for rectal cancer. Using their preoperative imaging data, investigate the correlation between APTw imaging and prognostic factors in rectal adenocarcinoma.

Results: APTw SI value are linked to T-stage and the presence of perineural invasion in rectal adenocarcinoma.

Impact: This study's results hold promise for the non-invasive identification of nerve invasion in rectal adenocarcinoma, offering a foundation for clinicians to pursue precise treatment strategies.

Keywords: Cancer, Tumor, colorectal cancer; microsatellite instability,DCE-MR, perfusion parameters,ADC

Motivation: To find an imaging method that can evaluate microsatellite status of colorectal cancer (CRC).

Goal(s): To investigate the value of DCE-MR perfusion parameters and ADC in predicting microsatellite instability of CRC. 

Approach: DCE-MR perfusion parameters, including Ktrans, Ve, kep, iAUC and ADC were compared between microsatellite instability (MSI) and microsatellite stability (MSS) CRC groups. Receiver operating characteristics (ROC) curve was drawn to evaluate diagnostic efficacy. 

Results: Univariable analysis revealed that kep had highest diagnostic accuracy (AUC, 0.890; sensitivity, 76.4%; specificity, 90.9%). The diagnostic accuracy of kep combined ADC was the greatest in multivariable analysis (AUC, 0.970; sensitivity, 90.0%; specificity, 100%).

Impact: The combination of DCE-MRI based kep value and DWI based ADC value can provide excellent diagnostic accuracy in non-invasively predicting microsatellite status. This study provides insight into potential application of multi-modality MRI in predicting patient with CRC.

Keywords: Cancer, Body, rectal cancer

Motivation: To improve the accuracy of rectal cancer staging via imaging techniques.

Goal(s): To explore the correlation between amide proton transfer (APT) imaging, intravoxel incoherent motion imaging (IVIM) quantitative parameters, and the pathological traits and prognostic markers of rectal adenocarcinoma.

Approach: Standard Magnetic resonance imaging (MRI), APT, and IVIM scans were performed on patients with suspected rectal cancer. Following this, APT and IVIM quantitative parameters were derived.

Results: Significant differences in D and D* values were observed across various T stages. However, no substantial variations in APT signal intensity (APTSI), D, D*, f were noted in different N stages, perineural invasion, and vascular invasion.

Impact: The research conducted has significant implications for the clinical staging of rectal cancer. By providing a more detailed and nuanced understanding of the disease's progression, it can aid in developing more precise and individualized treatment plans.

Keywords: Treatment Response, Tumor, complete response

Motivation: The existing evaluation system remains inadequate for assessing complete response(CR) to neoadjuvant therapy (NAT)  for locally advanced rectal cancer (LARC). There is a pressing need for more precise imaging evaluation methods. 

Goal(s): To investigate the added value of Amide Proton Transfer weighted (APTw) MRI in the evaluation of CR to NAT in patients with LARC.

Approach: Diagnosis performance of conventional assessment and APTw-added combined assessment was assessed by receiver operating characteristic curve (ROC) analysis. 

Results: Diagnostic efficiency in the evaluation of CR was significantly improved when APTw imaging was added to conventional evaluation, with AUC improved from 0.706 to 0.969

Impact: Superimposing the advantage of noninvasiveness, APTw imaging may have great application value in solving the clinical problem of diagnosing CR to NAT and provide additional valuable information for clinical decision making.

Keywords: Cancer, Diffusion/other diffusion imaging techniques

Motivation: The potential benefits of ultra-high b-value DWI have not yet been elucidated for clinical values of rectal cancer.

Goal(s): To evaluate image quality and lymph node metastasis in rectal cancer on multi-b value diffusion-weighted imaging (DWI_b1000, DWI_b2000 and DWI_b3000).

Approach: The image quality of three sets of DWI was measured by two radiologists independently. The radiomics model was trained on 70%, and tested on the remainder

Results: The DWI_b2000 exhibited excellent lesion conspicuity and was able to determine the outcome of of lymph node metastasis rectal with a predictive value of 0.728

Impact: The DWI_b2000 had great potential in improving detection of rectal cancer and was helpful to stratify the risk of lymph node metastasis of rectal cancer.

Keywords: Cancer, Digestive

Motivation: For the preoperative assessment of rectal cancer microcirculation use DCE ang IVIM.

Goal(s): To analyze the correlation between rectal cancer microvascular density, as indicated by CD34 immunohistochemistry, and quantitative parameters obtained from DCE and IVIM MRI.

Approach: Assess the correlation between quantitative imaging parameters from DCE and IVIM, and microvascular density.

Results: Significant differences in Ktrans and D values among different degrees of rectal cancer differentiation; furthermore, Ktrans, Kep, and D* values exhibited significant correlations with rectal cancer microvascular density, while Ve, D, and f did not show significant correlations.

Impact: The validation of the utility of non-invasive MRI techniques, particularly DCE and IVIM, assesses rectal cancer microcirculation, which can enhance early diagnosis and treatment planning for patients, ultimately improving the prognosis and management of rectal cancer.

Keywords: Treatment Response, Diffusion/other diffusion imaging techniques, Rectal Cancer

Motivation: Rectal cancer response assessment utilizes primarily T2 weighted and diffusion MRI. Reduced field of view diffusion has been shown to have higher imaqe quality and resolution than traditional EPI-based diffusion. 

Goal(s): We compare reduced field of view diffusion to mrTRG and sigmoidoscopy for assessment of clinical response.

Approach: 32 patient MRI were evaluated after treatment with short course radiation (30 Gy, 5 fractions), and FOLFOXIRI and assessed with mrTRG system, ADC on reduced field of view DWI, and sigmoidoscopy.

Results: Reduced field of view diffusion is highly accurate for assessment of clinical response nearly matching the performance of mrTRG and surpassing sigmoidoscopy.

Impact: Reduced field of view diffusion should be considered for use in clinical protocols assessing rectal cancer treatment response along with T2 weighted MRI and clinical assessment.

Keywords: Digestive, Cancer, Rectal cancer · Neoadjuvant chemoradiotherapy · Magnetic resonance imaging · Split scar sign · Complete response

Motivation: Patients with rectal cancer who have pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) are the best candidates to receive nonoperative management. An optimized method to identify these patients remains to be developed.

Goal(s): To measure the diagnostic performance of modified MRI-based split scar sign (mrSSS) score.

Approach: The sensitivity, specificity, and accuracy of modified mrSSS score, endoscopic gross type, and MRI-based tumor regression grading (mrTRG) score, in the prediction of pCR, were compared. The prognostic value was also studied.

Results: The modified mrSSS score had significantly higher sensitivity in predicting pCR. Patients with lower modified mrSSS scores had significantly longer disease-free survival.

Impact: The modified mrSSS score showed satisfactory interobserver agreement and higher sensitivity in predicting pCR after nCRT in patients with rectal cancer. The modified mrSSS score is also a predictor of disease-free survival.

Keywords: Screening, Hematologic, Proton density fat fraction

Motivation: PDFF quantification (PD-FFQ) with 6-point Dixon technique has a potential to assess hematopoietic ability assessment and diagnosis of aplastic anemia in adults.

Goal(s): The goal was to determine the capability of PD-FFQ with 6-point Dixon technique for diagnosis of aplastic anemia in adults.

Approach: Gender and age matched aplastic anemia patients and adults without aplastic anemia examined lumber MRI with PD-FFQ, and %CV and SD for vertebral bone marrow fat fraction were assessed and tested for differentiating two groups.

Results: When applied feasible threshold value, specificity of %CV was significantly higher than that of SD (p=0.03).  

Impact: Proton density fat fraction quantification (PD-FFQ) with 6-point Dixon technique has a potential for hematopoietic ability assessment and diagnosis of aplastic anemia in adults.

Keywords: fMRI Analysis, Segmentation

Motivation: By studying the application of ITSS ratio values measured under different threshold conditions, we hope to be able to quickly identify and predict abdominal tumors preoperatively. 

Goal(s): To explore the application value of automatic extraction of ITSS in abdominal tumors. 

Approach: Friedman The rank sum test was used to compare the differences of ITSS measurements under different threshold conditions.

Results: Under different threshold conditions, the ITSS ratios of uterine sarcoma, ovarian cystadenocarcinoma, hepatic vascular carcinoma and prostate cancer were respectively higher than those of degenerative uterine fibroids, ovarian cystadenomas, hepatic hemangioma and prostate hyperplasia. 

Impact: The automatic extraction of ITSS can effectively, quickly and subjectively predict the differential diagnosis of abdominal tumors under different threshold conditions, which has a good clinical application prospect.