Exploratory Analysis of the Role of Radiomic Features in the Differentiation of Oncocytoma and Chromophobe RCC in the Nephrographic CT Phase.

In diagnostic imaging, distinguishing chromophobe renal cell carcinomas (chRCCs) from renal oncocytomas (ROs) is challenging, since they both present similar radiological characteristics. Radiomics has the potential to help in the differentiation between chRCCs and ROs by extracting quantitative imaging. This is a preliminary study of the role of radiomic features in the differentiation of chRCCs and ROs using machine learning models. In this retrospective work, 38 subjects were involved: 19 diagnosed with chRCCs and 19 with ROs. The CT nephrographic contrast phase was selected in each case. Three-dimensional segmentations of the lesions were performed and the radiomic features were extracted. To assess the reliability of the features, the intraclass correlation coefficient was calculated from the segmentations performed by three radiologists with different degrees of expertise. The selection of features was based on the criteria of excellent intraclass correlation coefficient (ICC), high correlation, and statistical significance. Three machine learning models were elaborated: support vector machine (SVM), random forest (RF), and logistic regression (LR). From 105 extracted features, 41 presented an excellent ICC and 6 were not highly correlated with each other. Only two features showed significant differences according to histological type and machine learning models were developed with them. LR was the better model, in particular, with an 83% precision.

Gynaecological Causes of Acute Pelvic Pain: Common and Not-So-Common Imaging Findings.

In female patients, acute pelvic pain can be caused by gynaecological, gastrointestinal, and urinary tract pathologies. Due to the variety of diagnostic possibilities, the correct assessment of these patients may be challenging. The most frequent gynaecological causes of acute pelvic pain in non-pregnant women are pelvic inflammatory disease, ruptured ovarian cysts, ovarian torsion, and degeneration or torsion of uterine leiomyomas. On the other hand, spontaneous abortion, ectopic pregnancy, and placental disorders are the most frequent gynaecological entities to cause acute pelvic pain in pregnant patients. Ultrasound (US) is usually the first-line diagnostic technique because of its sensitivity across most common aetiologies and its lack of radiation exposure. Computed tomography (CT) may be performed if ultrasound findings are equivocal or if a gynaecologic disease is not initially suspected. Magnetic resonance imaging (MRI) is an extremely useful second-line technique for further characterisation after US or CT. This pictorial review aims to review the spectrum of gynaecological entities that may manifest as acute pelvic pain in the emergency department and to describe the imaging findings of these gynaecological conditions obtained with different imaging techniques.

Pilot Study for the Assessment of the Best Radiomic Features for Bosniak Cyst Classification Using Phantom and Radiologist Inter-Observer Selection.

Since the Bosniak cysts classification is highly reader-dependent, automated tools based on radiomics could help in the diagnosis of the lesion. This study is an initial step in the search for radiomic features that may be good classifiers of benign-malignant Bosniak cysts in machine learning models. A CCR phantom was used through five CT scanners. Registration was performed with ARIA software, while Quibim Precision was used for feature extraction. R software was used for the statistical analysis. Robust radiomic features based on repeatability and reproducibility criteria were chosen. Excellent correlation criteria between different radiologists during lesion segmentation were imposed. With the selected features, their classification ability in benignity-malignity terms was assessed. From the phantom study, 25.3% of the features were robust. For the study of inter-observer correlation (ICC) in the segmentation of cystic masses, 82 subjects were prospectively selected, finding 48.4% of the features as excellent regarding concordance. Comparing both datasets, 12 features were established as repeatable, reproducible, and useful for the classification of Bosniak cysts and could serve as initial candidates for the elaboration of a classification model. With those features, the Linear Discriminant Analysis model classified the Bosniak cysts in terms of benignity or malignancy with 88.2% accuracy.

Renal Angiomyolipoma: A Diagnostic and Therapeutic Challenge.

BACKGROUND: Angiomyolipomas (AML) represent less than 10% of renal tumours. They are most often detected incidentally during imaging tests, but there are several histological variants that pose difficulties in the radiological differential diagnosis. Their identification should allow the loss of renal parenchyma due to embolization or radical surgery to be prevented. METHODS: Retrospective study of patients undergoing kidney surgery with post-surgical pathological diagnosis of AML at the Álvaro Cunqueiro Hospital (2016-2021). Patients with a radiological diagnosis of AML who underwent surgery based on clinical criteria were excluded. RESULTS: 18 patients were registered, allowing for the assessment of 18 renal tumours. All of the cases were diagnosed incidentally. Preoperative radiological diagnosis was: 9 lesions suggestive of renal cell carcinoma (RCC) (50%), 7 cases suggestive of RCC vs. AML (38.9%) and 2 lesions suggestive of AML vs. retroperitoneal liposarcoma (11.1%). Histological variants of AML were found in 61.1% of cases (n = 11). The most widely used surgical technique was partial nephrectomy, in 66.67% of cases. CONCLUSIONS: The radiological differential diagnosis of AML, and particularly its variants, with malignant lesions have important limitations either due to the predominance or scarcity of any of the AML components. Some cases can also pose difficulties at the histological level. This fact highlights the importance of the specialization of uroradiologists and uropathologists and the performance of kidney-sparing therapeutic techniques.

Renal Angiomyolipoma: A Diagnostic and Therapeutic Challenge

Background: Angiomyolipomas (AML) represent less than 10% of renal tumours. They are most often detected incidentally during imaging tests, but there are several histological variants that pose difficulties in the radiological differential diagnosis. Their identification should allow the loss of renal parenchyma due to embolization or radical surgery to be prevented. Methods: Retrospective study of patients undergoing kidney surgery with post-surgical pathological diagnosis of AML at the Álvaro Cunqueiro Hospital (2016–2021). Patients with a radiological diagnosis of AML who underwent surgery based on clinical criteria were excluded. Results: 18 patients were registered, allowing for the assessment of 18 renal tumours. All of the cases were diagnosed incidentally. Preoperative radiological diagnosis was: 9 lesions suggestive of renal cell carcinoma (RCC) (50%), 7 cases suggestive of RCC vs. AML (38.9%) and 2 lesions suggestive of AML vs. retroperitoneal liposarcoma (11.1%). Histological variants of AML were found in 61.1% of cases (n = 11). The most widely used surgical technique was partial nephrectomy, in 66.67% of cases. Conclusions: The radiological differential diagnosis of AML, and particularly its variants, with malignant lesions have important limitations either due to the predominance or scarcity of any of the AML components. Some cases can also pose difficulties at the histological level. This fact highlights the importance of the specialization of uroradiologists and uropathologists and the performance of kidney-sparing therapeutic techniques (AU)

MRI of female genital tract congenital anomalies: European Society of Urogenital Radiology (ESUR) guidelines.

OBJECTIVE: To develop imaging guidelines for the MR work-up of female genital tract congenital anomalies (FGTCA). METHODS: These guidelines were prepared based on a questionnaire sent to all members of the European Society of Urogenital Radiology (ESUR) Female Pelvic Imaging Working Group (FPI-WG), critical review of the literature and expert consensus decision. RESULTS: The returned questionnaires from 17 different institutions have shown reasonable homogeneity of practice. Recommendations with focus on patient preparation and MR protocol are proposed, as these are key to optimised examinations. Details on MR sequences and planning of uterus-orientated sequences are provided. CONCLUSIONS: The multiplanar capabilities and soft tissue resolution of MRI provide superb characterisation of the wide spectrum of findings in FGTCA. A standardised imaging protocol and method of reporting ensures that the salient features are recognised, contributing to a correct diagnosis and classification of FGTCA, associated anomalies and complications. These imaging guidelines are based on current practice among expert radiologists in the field and incorporate up to date information regarding MR protocols and essentials of recently published classification systems. KEY POINTS: • MRI allows comprehensive evaluation of female genital tract congenital anomalies, in a single examination. • A dedicated MRI protocol comprises uterus-orientated sequences and vaginal and renal evaluation. • Integration of classification systems and structured reporting helps in successful communication of the imaging findings.

Endometrial Cancer MRI staging: Updated Guidelines of the European Society of Urogenital Radiology.

OBJECTIVES: To update the 2009 ESUR endometrial cancer guidelines and propose strategies to standardize image acquisition, interpretation and reporting for endometrial cancer staging with MRI. METHODS: The published evidence-based data and the opinion of experts were combined using the RAND-UCLA Appropriateness Method and formed the basis for these consensus guidelines. The responses of the experts to 81 questions regarding the details of patient preparation, MR imaging protocol, image interpretation and reporting were collected, analysed and classified as "RECOMMENDED" versus "NOT RECOMMENDED" (if at least 80% consensus among experts) or uncertain (if less than 80% consensus among experts). RESULTS: Consensus regarding patient preparation, MR image acquisition, interpretation and reporting was determined using the RAND-UCLA Appropriateness Method. A tailored MR imaging protocol and a standardized report were recommended. CONCLUSIONS: These consensus recommendations should be used as a guide for endometrial cancer staging with MRI. KEY POINTS: • MRI is recommended for initial staging of endometrial cancer. • MR imaging protocol should be tailored based on the risk of lymph node metastases. • Myometrial invasion is best assessed using combined axial-oblique T2WI, DWI and contrast-enhanced imaging. • The mnemonic "Clinical and MRI Critical TEAM" summarizes key elements of the standardized report.

Stromal prostatic sarcoma: a rare tumor with rare clinical and imaging presentation.

Adult prostatic stromal sarcoma is a rare malignant tumor. The main presenting symptom is urinary retention secondary to bladder outlet obstruction. Prostatic Specific Antigen level can be normal. Imaging features show a prostate mass with or without pelvic organ invasion depending on the aggressiveness of the tumor. We present a patient with prostatic stromal sarcoma who debuted with urinary obstruction, leukocytosis and neutrophilia, prostate enlargement, and hypodense prostate areas on CT images, simulating prostatitis with abscess formation.

[Local recurrence after radical prostatectomy and salvage radiotherapy]. / Recidiva local después de la prostatectomía radical y radioterapia de rescate.

OBJECTIVE: To evaluate the efficacy of radiotherapy to the prostatic bed in patients with biochemical recurrence prostate cancer after radical prostatectomy. METHODS: We analyse the outcomes of 292 patients who underwent radical prostatectomy for localized prostate cancer T1-T2 between January 1992 and June 2003, with an average follow-up of 36 months (range 6 months to 12 years). We detected biochemical recurrence (PSA > 0.20 ng/ml) in 75 (26%) patients. 75 patients with biochemical recurrence, 9 (12%) were diagnosed of local recurrence by the following criteria: a) First PSA obtained 6 weeks after radical prostatectomy < 0.20 ng/ml. b) Time to biochemical recurrence > 6 months. c) Prostate specific antigen doubling time > 6 months. d) Prostate specific antigen velocity after radical prostatectomy < 0.75 ng/ml/year. e) Prostate specific antigen level after radical prostatectomy < 2.5 ng/ml. The 9 patients diagnosed of local recurrence received an average dose of 56.42 Gy to the prostate bed. RESULTS: Of all 9 patients with local recurrence, 8(88.8%) have complete response with a mean follow-up of 30 months (12-36 months). The time between the radiotherapy and the response, in patients with complete response, was lower than 3 months in 7 patients and 12 months in 1 patient. Significant adverse effects associated to radiotherapy were not observed. CONCLUSIONS: Salvage radiotherapy may be beneficial in selected patients with local recurrence. The characteristics of prostate specific antigen elevation are useful in distinguishing men with local recurrence from those with distant metastases.

Recidiva local después de la prostatectomía radical y radioterapia de rescate / Local recurrence after radical prostatectomy and salvage radiotherapy

OBJETIVO: Evaluar la eficacia de laradioterapia en el lecho prostático en pacientes concáncer de próstata y fracaso bioquímico después de laprostatectomía radical.MÉTODOS: Analizamos los resultados de 292 pacientesa los que se le practicó prostatectomía radical porcancer de próstata localizado T1-T2, entre Enero de1992 y Junio de 2003, con un seguimiento medio de36 meses(rango 6 meses a 12 años). Se detecta fracasobioquímico(PSA > 0.20 ng/ml) en 75(26%)pacientes. De los 75 pacientes con fracaso bioquímico,9(12%) se diagnosticó de recidiva local siguiendolos siguientes criterios: a/ Primer PSA obtenido a las 6semanas de la intervención 6 meses. c/ Tiempo deduplicación del PSA > 6 meses. d/ Velocidad de PSAdespués de la prostatectomía radical <0.75/ng/ml/año. e/ Nivel de PSA después de laprostatectomía radical < 2.5 ng/ml. Los 9 pacientesdiagnosticados de recidiva local reciben una dosismedia de 56.42 Gy en el lecho prostático.RESULTADOS: De los 9 pacientes diagnosticados derecidiva local, en 8(88.8%) se obtuvo una respuestacompleta durante una mediana de seguimiento de 30meses(12-36 meses). El tiempo entre la radioterapia yla respuesta, en los pacientes con respuesta completa,fue inferior a los 3 meses en 7 pacientes y a 12 mesesen 4 pacientes. No se observaron efectos adversosimportantes secundarios a la radioterapia.CONCLUSIONES: La radioterapia de rescate puedeser beneficiosa en un seleccionado grupo de pacientescon recidiva local. La cinética del PSA después de laprostatectomía radical es útil para distinguir las recidivaslocales de las metástasis a distancia

OBJETIVE: To evaluate the efficacy ofradiotherapy to the prostatic bed in patients withbiochemical recurrence prostate cancer after radicalprostatectomy.METHODS: We analyse the outcomes of 292 patientswho underwent radical prostatectomy for localizedprostate cancer T1-T2 between January 1992 and June2003, with an average folow-up of 36 months (range6 months to 12 years). We detected biochemical recurrence(PSA > 0.20 ng/ml) in 75(26%) patients. 75 patientswith biochemical recurrence, 9 (12 %) were diagnosedof local recurrence by the following criteria: a) First PSAobtained 6 weeks after radicalprostatectomy 6 months. c) Prostate specific antigen doublingtime > 6 months. d) Prostate specific antigen velocityafter radical prostatectomy < 0.75 ng/ml/year. e)Prostate specific antigen level after radical prostatectomy< 2.5 ng/ml. The 9 patients diagnosed of local recurrencereceived an average dose of 56.42 Gy to the prostatebed.RESULTS: Of all 9 patients with local recurrence,8(88.8%) have complete response with a mean followupof 30 months (12-36 months). The time between theradiotherapy and the response, in patients with completeresponse, was lower than 3 months in 7 patients and12 months in 1 patient. Significant adverse effectsassociated to radiotherapy were not observed.CONCLUSIONS: Salvage radiotherapy may be beneficialin selected patients with local recurrence. The characteristicsof prostate specific antigen elevation are useful indistinguishing men with local recurrence from those withdistant metastases