Rectal MRI

BACKGROUND: Standardized assessments of clinical complete response (cCR) to neoadjuvant chemoradiotherapy (nCRT) for rectal cancer have been established, but their utility and accuracy remain unclear. This study aimed to evaluate the clinical diagnostic value of rectal magnetic resonance imaging (MRI) and endorectal ultrasonography (ERUS) for the determination of cCRs after neoadjuvant immunotherapy and to investigate the concordance between cCR and pathological complete response (pCR)...

OBJECTIVE: To investigate the effectiveness of a multimodal deep learning model in predicting tumor budding (TB) grading in rectal cancer (RC) patients. MATERIALS AND METHODS: A retrospective analysis was conducted on 355 patients with rectal adenocarcinoma from two different hospitals. Among them, 289 patients from our institution were randomly divided into an internal training cohort (n = 202) and an internal validation cohort (n = 87) in a 7:3 ratio, while an additional 66 patients from another hospital constituted an external validation cohort...

We present a case report of a 73-year-old male patient with a complete clinical response following neoadjuvant radiochemotherapy of mid-rectal adenocarcinoma. The patient was initially diagnosed with stage IIIB microsatellite stable mid-rectal adenocarcinoma in February 2017. During restaging in June 2017, which included rectoscopy, endosonography, computed tomography and magnetic resonance imaging, a complete clinical response was observed. After appropriate consultation, a watch-and-wait strategy was chosen...

PURPOSE: This study assessed the feasibility of using three-dimensional (3D) models of intrapelvic vascular patterns constructed using computed tomography (CT) and magnetic resonance imaging (MRI) fusion data for preoperative planning in patients with locally recurrent rectal cancer. METHODS: Eleven patients scheduled for pelvic exenteration were included. The 3D fusion data of the intrapelvic vessels constructed using CT and MRI with true fast imaging with steady-state precession sequence (True FISP) were evaluated preoperatively...

BACKGROUND AND PURPOSE: Magnetic Resonance Imaging (MRI)-guided Stereotactic body radiotherapy (SBRT) treatment to prostate bed after radical prostatectomy has garnered growing interests. The aim of this study is to evaluate intra-fractional anatomic and dose/volume metric variations for patients receiving this treatment. MATERIALS AND METHODS: Nineteen patients who received 30-34 Gy in 5 fractions on a 0.35T MR-Linac were included. Pre- and post-treatment MRIs were acquired for each fraction (total of 75 fractions)...

Locally recurrent rectal cancer (LRRC) involving the lateral pelvic sidewall requires a complex approach to maximize the likelihood of R0 resection, which is the only predictor of survival. The purpose of this report is to describe a novel technique to resect a localized lateral pelvic sidewall LRRC. A 63-year-old male patient was referred for a 15-mm LRRC near the right internal iliac vessels. Endoscopic ultrasound and magnetic resonance imaging excluded any involvement of the pelvic colon or residual rectum...

BACKGROUND: Detection of grade 3-4 extra mural venous invasion (mrEMVI) on magnetic resonance imaging (MRI) is associated with an increased distant metastases (DM)-rate. This study aimed to determine the impact of different grades of mrEMVI and their disappearance after neoadjuvant therapy. METHODS: A Dutch national retrospective cross-sectional study was conducted, including patients who underwent resection for rectal cancer in 2016 from 60/69 hospitals performing rectal surgery...

Endoanal ultrasound (EAUS) is a valuable imaging modality for the evaluation of anal and perianal pathologies. It provides detailed information about the anatomy and physiology of the anorectal region and has been used in pre-and post-operative settings of anorectal pathologies. EAUS is not only useful in the evaluation of benign pathologies but also in loco-regional staging of anal and rectal tumors. EAUS has several advantages over MRI, including reduced cost, better patient tolerance, and improved scope of application in patients with contraindications to MRI...

PURPOSE: Residual lymph node metastases (RLNM) remained a great concern in the implementation of organ-preserving strategies and led to poor prognosis in locally advanced rectal cancer (LARC). In this study, we aimed to identify the clinicopathological factors correlated with RLNM in LARC patients with ypT0-2 after neoadjuvant chemoradiotherapy (NCRT). METHODS: We retrospectively analyzed 417 patients histologically diagnosed middle-low LARC after NCRT and total mesorectal excision (TME), whose pathological staging was ypT0-2...

BACKGROUND: With the continuous development of deep learning algorithms in the field of medical images, models for medical image processing based on convolutional neural networks have made great progress. Since medical images of rectal tumors are characterized by specific morphological features and complex edges that differ from natural images, achieving good segmentation results often requires a higher level of enrichment through the utilization of semantic features. PURPOSE: The efficiency of feature extraction and utilization has been improved to some extent through enhanced hardware arithmetic and deeper networks in most models...

PURPOSE: To evaluate the outcomes of post-neoadjuvant chemoradiation (NACTRT) wait-and-watch Strategy (WWS) in distal rectal cancers. MATERIALS AND METHODS: All consecutive patients from December 2012 to 2019 diagnosed with distal rectal tumors (T2-T4 N0-N+) having a complete or near-complete response (cCR or nCR, respectively) post-NACTRT and wishing for the non-surgical treatment option of WWS were included in this study. Patients were observed with 3 monthly magnetic resonance imaging (MRIs), sigmoidoscopies, and digital rectal examination for 2 years and 6 monthly thereafter...

Multiple myeloma (MM) and bone metastases are both common malignant tumors of the skeleton that share similar clinical manifestations and radiological features. The development of MM following rectal cancer surgery is relatively rare in clinical practice and is easily misdiagnosed as bone metastasis. The present study reported on a patient with MM and postoperative rectal cancer. A 65-year-old man had been diagnosed with low rectal cancer (poorly differentiated, T3N1M0) 10 years prior and underwent curative treatment at that time...

BACKGROUND: Paragangliomas of the urinary tract are exceptionally uncommon, and sporadic case reports of primary paraganglioma of the prostate have been reported in the literature. METHODS: Systematic research in PubMed/Medline and Scopus databases concerning primary prostatic paraganglioma was performed by two independent investigators. RESULTS: This analysis included 25 adult males, with a mean age of 49.8 ± 22.4 years. 32% of included patients had a history of hypertension...

Treatment response assessment of rectal cancer patients is a critical component of personalized cancer care and it allows to identify suitable candidates for organ-preserving strategies. This pilot study employed a novel multi-omics approach combining MRI-based radiomic features and untargeted metabolomics to infer treatment response at staging. The metabolic signature highlighted how tumor cell viability is predictively down-regulated, while the response to oxidative stress was up-regulated in responder patients, showing significantly reduced oxoproline values at baseline compared to non-responder patients (p-value < 10-4 )...

The aim of this study was to determine the most appropriate sedation protocol for a standing magnetic resonance imaging (MRI) examination in horses, comparing continuous rate infusions (CRIs) of detomidine and romifidine combined with a single bolus of morphine. Sixteen horses referred for standing low-field open-magnet MRI were randomly assigned to one of two sedation protocols. The horses were premedicated with 0.03 mg/kg of intramuscular acepromazine, and those animals belonging to Group D received an intravenous (IV) loading dose of detomidine (0...

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Background Detection of extranodal extension (ENE) at pathology is a poor prognostic indicator for rectal cancer, but whether ENE can be identified at pretreatment MRI is, to the knowledge of the authors, unknown. Purpose To evaluate the performance of pretreatment MRI in detecting ENE using a matched pathologic reference standard and to assess its prognostic value in patients with rectal cancer. Materials and Methods This single-center study included a prospective development data set consisting of participants with rectal adenocarcinoma who underwent pretreatment MRI and radical surgery (December 2021 to January 2023)...

PURPOSE: To investigate the predictive factors of pathologic complete response (pCR) in locally advanced rectal cancer (LARC) patients who had been treated with neoadjuvant chemoradiation (nCRT). METHODS AND MATERIALS: For this retrospective study, 53 LARC patients (37 males and 16 females; age range 25 to 79 years) were selected. Clinical characteristics, baseline mrTNM staging, MR gross tumor volumes (GTV), and pCR were evaluated. The diagnostic accuracy of GTV for predicting pCR was calculated...

PURPOSE: Non-invasive methods for predicting pathological complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) can provide distinct leverage in the management of patients with locally advanced rectal cancer (LARC). This study aimed to investigate whether including the golden-angle radial sparse parallel (GRASP) dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) perfusion parameter (Ktrans ), in addition to tumor regression grading (TRG) and apparent diffusion coefficient (ADC) values, can improve the predictive ability for pCR...

OBJECTIVE: To measure inter-reader agreement and identify associated factors in interpreting complete response (CR) on magnetic resonance imaging (MRI) following chemoradiotherapy (CRT) for rectal cancer. MATERIALS AND METHODS: This retrospective study involved 10 readers from seven hospitals with experience of 80-10210 cases, and 149 patients who underwent surgery after CRT for rectal cancer. Using MRI-based tumor regression grading (mrTRG) and methods employed in daily practice, the readers independently assessed mrTRG, CR on T2-weighted images (T2WI) denoted as mrCRT2W , and CR on all images including diffusion-weighted images (DWI) denoted as mrCRoverall ...