The CARTS study is a multicenter feasibility study, investigating the role of rectum saving surgery for distal rectal cancer. Patients with a clinical T1-3 N0 M0 rectal adenocarcinoma below 10 cm from the anal verge will receive neoadjuvant chemoradiation therapy (25 fractions of 2 Gy with concurrent capecitabine). Transanal Endoscopic Microsurgery (TEM) will be performed 8 - 10 weeks after the end of the preoperative treatment depending on the clinical response. Primary objective is to determine the number of patients with a (near) complete pathological response after chemoradiation therapy and TEM. Secondary objectives are the local recurrence rate and quality of life after this combined therapeutic modality. A three-step analysis will be performed after 20, 33 and 55 patients to ensure the feasibility of this treatment protocol. The CARTS-study is one of the first prospective multicentre trials to investigate the role of a rectum saving treatment modality using chemoradiation therapy and local excision. The CARTS study is registered at clinicaltrials.gov ( NCT01273051 )

OBJECTIVE. The purpose of this study was to evaluate the role of MRI in the diagnosis and differential diagnosis of urethral diverticula in symptomatic women. MATERIALS AND METHODS. Women referred for MRI at a single institution because of suspicion of urethral diverticula were included. All MRI examinations were independently evaluated by two radiologists and compared with patients' follow-up data. Sensitivity and specificity of MRI for urethral diverticula were calculated using surgery and clinical confirmation as the reference standards. Image quality of the urethra and periurethral region performed with the endoluminal coil was compared with the pelvic phased-array coil. RESULTS. From a study group of 60 patients (mean age, 44 years), 20 patients (33%) had urethral diverticula and 28 (47%) had an alternative diagnosis, of which 13 (46%) were visualized with MRI. In the remaining 12 patients (20%) no abnormalities were found. For urethral diverticula, MRI had both sensitivity and specificity of 100%. T...

Treatment planning of gastrointestinal stromal tumors (GISTs) includes distinguishing GISTs from other intra-abdominal tumors and GISTs’ molecular analysis. The aim of this study was to evaluate radiomics for distinguishing GISTs from other intra-abdominal tumors, and in GISTs, predict the c-KIT, PDGFRA, BRAF mutational status, and mitotic index (MI). Patients diagnosed at the Erasmus MC between 2004 and 2017, with GIST or non-GIST intra-abdominal tumors and a contrast-enhanced venous-phase CT, were retrospectively included. Tumors were segmented, from which 564 image features were extracted. Prediction models were constructed using a combination of machine learning approaches. The evaluation was performed in a 100 × random-split cross-validation. Model performance was compared to that of three radiologists. One hundred twenty-five GISTs and 122 non-GISTs were included. The GIST vs. non-GIST radiomics model had a mean area under the curve (AUC) of 0.77. Three radiologists had an AUC of 0.69, 0.76, and 0.84, respectively. The radiomics model had an AUC of 0.52 for c-KIT, 0.56 for c-KIT exon 11, and 0.52 for the MI. The numbers of PDGFRA, BRAF, and other c-KIT mutations were too low for analysis. Our radiomics model was able to distinguish GISTs from non-GISTs with a performance similar to three radiologists, but less observer dependent. Therefore, it may aid in the early diagnosis of GIST, facilitating rapid referral to specialized treatment centers. As the model was not able to predict any genetic or molecular features, it cannot aid in treatment planning yet.

Perianal fistulizing disease, commonly associated with Crohn’s disease, poses significant diagnostic and therapeutic challenges due to its complex anatomy and high recurrence rates. Radiological imaging plays a pivotal role in the accurate diagnosis, classification, and management of this condition. This article reviews the current radiological modalities employed in the evaluation of perianal fistulizing disease, including magnetic resonance imaging (MRI), endoanal ultrasound, and computed tomography (CT). MRI, recognized as the gold standard, offers superior soft tissue contrast and multiplanar capabilities, facilitating detailed assessment of fistula tracts and associated abscesses. CT, although less detailed than MRI, remains valuable in acute settings for detecting abscesses and guiding drainage procedures. This article discusses the advantages and limitations of each modality, highlights the importance of standardized imaging protocols, and underscores the need for interdisciplinary collaboration in the management of perianal fistulizing disease. Future directions include advancements in imaging techniques and the integration of artificial intelligence to enhance diagnostic accuracy and treatment outcomes.

OBJECTIVE. The purpose of this study was to assess the a priori chance that primary cystic lesions of the retrorectal space are malignant and to investigate MRI characteristics that indicate malignancy. MATERIALS AND METHODS. Patients referred to a center for colorectal surgery were recruited from 2000 to 2014. Lesions were proven by clinical assessment and histopathology. MRI was performed at 1.5 T with examinations evaluated by two radiologists. Interobserver agreement was assessed (Cohen kappa) and differences between malignant and benign lesions calculated (Fisher exact test). RESULTS. Twenty-eight patients (22 women, six men; age range, 18–70 years) with 31 lesions were included. Lesions were categorized as tailgut cysts (n = 16, 52%), teratomas (n = 9, 29%), lesions of colorectal origin (n = 4, 13%), or neurogenic lesions (n = 2, 6%). Five patients (18%) had malignant lesions. Colorectal lesions had the highest percentage of malignancy (3/4, 75%). A solid tissue component was found in all five (100%...

OBJECTIVE. The purpose of this study was to assess the diagnostic value of anorectal MRI in the care of patients with chronic anal and perianal pain but without findings of abnormalities in the clinical workup. MATERIALS AND METHODS. Patients referred from a tertiary department of colorectal surgery to the MRI unit with clinically occult chronic anal and perianal pain were included. MRI of the anorectum was performed with an endoanal or pelvic phased-array coil. The images from all examinations were read by two radiologists. MRI findings were correlated with clinical follow-up data. RESULTS. The study group (103 patients) was stratified into patients with no history of anorectal disease (n = 60) and those who had a history of surgery for anorectal disease (n = 43). MRI findings suggested the final diagnoses in 40 patients (39%). These diagnoses were 28 cases of suppurative lesions (27%), 11 cases of painful scarring of the anus (11%), and one case of metastasis to the sacrum (1%). Suppurative lesions were surgically proved with marked relief of pain after surgery. In the other patients the final diagnoses were 37 cases of levator ani syndrome (36%) and 26 cases of unspecified functional anorectal pain (25%). No MRI abnormalities were found in 33 of the patients with levator ani syndrome and 26 of the patients with unspecified anorectal pain. The two readers had very good agreement (κ = 0.92). The patients with a history of anorectal disease had significantly more MRI findings of abnormalities (60%) than did patients without a history of anorectal disease (23%). The positive predictive value of MRI was 91%, and the negative predictive value was 100%. CONCLUSION. In 39% of patients, MRI showed abnormalities that were clinically confirmed as the final diagnosis. Surgical treatment will especially benefit patients with suppurative lesions, resulting in relief of pain.