Mini-review: Evaluation and Management of Retroperitoneal Masses in Patients with Testicular Cancer.

Testicular germ cell tumours (GCTs) account for the majority of testicular malignancies. Seminomas and nonseminomas differ in prognosis and management strategies. While cisplatin-based chemotherapy has significantly improved survival rates, identification of residual masses after chemotherapy is crucial for determining further treatment and survival. For seminomas, spontaneous resolution of residual masses occurs in a significant percentage of cases. Fluorodeoxyglucose positron emission tomography (FDG PET) is recommended for evaluation of residual masses after chemotherapy. Retroperitoneal lymph node dissection (RPLND) offers therapeutic benefits but is challenging because of an increase in desmoplasia after chemotherapy. For nonseminomas, residual masses are common after chemotherapy, with surgical resection necessary for masses larger than 1 cm. FDG PET has limited utility, and timely surgical intervention is crucial for favourable outcomes. Teratoma, if left unresected, can lead to serious complications, including growing teratoma syndrome, malignant transformation, and late relapse. Extraretroperitoneal residual masses, particularly those containing teratoma, are associated with poorer prognosis. Surgical resection remains the mainstay treatment, with significantly higher progression-free and recurrence-free survival rates for fibrosis/necrosis in comparison to teratoma or viable cancer. Understanding the characteristics and management of residual masses after chemotherapy is paramount for optimising treatment strategies and improving patient outcomes in testicular GCT. PATIENT SUMMARY: We reviewed treatment options for patients with testicular cancer who still have tumour tissue in the lower abdomen after chemotherapy. Surgical removal of the tumour is the main option; removal of lymph nodes can also help, but may be difficult because of tissue reactions to chemotherapy. Survival rates differ according to the tumour type and are lower for tumours beyond the lower abdomen.

The value of contrast-enhanced ultrasound in differentiating benign from malignant retroperitoneal masses.

OBJECTIVES: To evaluate the value of contrast-enhanced ultrasound (CEUS) perfusion patterns in the differentiation of benign and malignant retroperitoneal masses (RMs). METHODS: Between 2006 and 2023, 122 consecutive patients with an RM visualizable by B-mode US were investigated additionally with CEUS. On CEUS, the extent of enhancement (classified as marked, reduced, or absent) and the homogeneity of enhancement (HE; classified as homogeneous or inhomogeneous) were evaluated. Subsequently, the malignancy rate according to CEUS perfusion patterns was determined. RESULTS: On CEUS, marked enhancement was significantly more frequently associated with malignancy than with benignity (p < 0.0001, Fisher's exact test). All lesions with no enhancement were benign. Regarding HE, there was no significant difference between benign and malignant lesions (p = 0.07, Fisher's exact test). CONCLUSION: On CEUS, marked enhancement in an RM may be indicative of a malignant lesion. Furthermore, absent enhancement can be considered to be an indication of benignity. The use of CEUS can be helpful in the evaluation of the malignancy of retroperitoneal masses.

Overview of F18-FDG uptake patterns in retroperitoneal pathologies: imaging findings, pitfalls, and artifacts.

INTRODUCTION: Retroperitoneum can be the origin of a wide variety of pathologic conditions and potential space for disease spread to other compartments of the abdomen and pelvis. Computed tomography (CT) and magnetic resonance imaging (MRI) are often the initial imaging modalities to evaluate the retroperitoneal pathologies, however given the intrinsic limitations, F18-FDG PET/CT provides additional valuable metabolic information which can change the patient management and clinical outcomes. We highlight the features of retroperitoneal pathologies on F18-FDG PET/CT and the commonly encountered imaging artifacts and pitfalls. The aim of this review is to characterize primary and secondary retroperitoneal pathologies based on their metabolic features, and correlate PET findings with anatomic imaging. CONCLUSION: Retroperitoneal pathologies can be complex, ranging from oncologic to a spectrum of non-oncologic disorders. While crosse-sectional imaging (CT and MRI) are often the initial imaging modalities to localize and characterize pathologies, metabolic information provided by F18-FDG PET/CT can change the management and clinical outcome in many cases.

Masas retroperitoneales en el período perinatal / Retroperitoneal masses in the perinatal period

Objetivo: identificar las causas más frecuentes de masa retroperitoneal durante el período fetal y neonatal e ilustrar los hallazgos imagenológicos basados en los resultados obtenidos de nuestra experiencia. Material y método: estudio retrospectivo observacional de las causas de masas retroperitoneales en recién nacidos (RN). Se analizaron historias clínicas y hallazgos radiológicos y ultrasonográficos de 487 neonatos a los que se les había realizado ecografía abdominal entre enero de 2008 y diciembre de 2009. Se seleccionaron 47 RN con diagnóstico de lesión retroperitoneal, respetando los siguientes criterios: Inclusión: pacientes con diagnóstico ecográfico prenatal de masa intraabdominal retroperitoneal y neonatos que presentaron al examen físico masa abdominal palpable y fueron estudiados con diferentes técnicas de diagnóstico por imagen. Exclusión: neonatos con patología abdominal gastrointestinal e intraperitoneal. Resultados: del total de pacientes (n =47), 42 presentaron masas de origen renal (89%) y 5 retroperitoneal extrarrenal (11%). Las patologías prevalentes fueron hidronefrosis con 36 casos (76%) y displasia renal multiquística con 4 (9%). Se registró un caso de nefroma mesoblástico congénito y 1 con enfermedad poliquística autosómica recesiva. Se detectaron 3 RN con hemorragia suprarrenal (6%) y 2 con neuroblastoma (4%). Conclusión: la incidencia de Masas Retroperitoneales en la población estudiada fue del 9,65%, coincidente con la bibliografía. El presente trabajo destaca el valor del US prenatal, importante para definir conducta obstétrica, y la coordinación entre la ecografía pre y posnatal para lograr una mayor aproximación al diagnóstico. El rol fundamental de la TC para definir conducta quirúrgica en el nefroma mesoblástico congénito y para estadificación en los casos de neuroblastoma.

Purpose: To identify the most frequent causes of retroperitoneal mass during the fetal and neonatal period, and to illustrate the imaging findings based on our experience. Material and Methods: Retrospective study about the etiology of retroperitoneal masses in newborns based on x-ray analysis, ultrasound and clinical findings of 487 infants who underwent abdominal ultrasound between January 2008 and December 2009. A total of 47 newborns with a diagnosis of retroperitoneal mass were selected. Patients with prenatal ultrasound diagnosis of intraabdominal retroperitoneal mass and those with palpable abdominal mass on their physical examination in the neonatal period were included in this sample. Infants with gastrointestinal and intraperitoneal abdominal pathology were excluded. Results: Of all the study patients (n= 47), 42 had renal masses (89%), and 5 retroperitoneal extrarenal masses (11%). Among the former, the prevalent diseases were hydronephrosis in 36 cases (76%), and multicystic renal dysplasia in 4 (9%). Moreover, there was only 1 case of congenital mesoblastic nephroma, and 1 case of autosomal recessive polycystic disease. Among the latter, there were 3 infants with adrenal hemorrhage (6%), and 2 with neuroblastoma (4%). Conclusion: The incidence of perinatal retroperitoneal masses in the studied population was 9.65%, in agreement with the literature. It highlights the importance of prenatal US to define the obstetric behavior and the coordination between pre- and postnatal ultrasound in order to achieve the best diagnostic approach. In our casuistic, a diagnosis was reached through US in 94% of the cases. CT plays a crucial role in both defining the surgical procedure in congenital mesoblastic nephroma and staging neuroblastomas.