Introduction: Liposarcomas are the most common of all sarcomas. A well-differentiated liposarcoma can transform into a dedifferentiated liposarcoma with myogenic, osteo- or chondrosarcomatous heterologous differentiation. Genomic amplification of MDM2 gene is then characteristic. Treatment usually involves surgical resection to radically remove the tumor. Other treatments such as chemotherapy and radiotherapy may also be used. Case report: A 60-year-old patient was admitted to the hospital for surgical treatment of a left renal mass. The true location of the tumor was discovered only intraoperatively. The lesion was completely removed laparoscopically with preservation of the capsule. Genomic amplification of MDM2 gene was confirmed. One and a half years after surgery, despite the removal of the tumor without the surrounding margin of healthy tissue, the patient remains without recurrence. Conclusion: Dedifferentiated liposarcoma with osteosarcomatous differentiation is a sporadic case and may occur in various locations of the retroperitoneal space, also mimicking a renal tumor. The laparoscopic technique is a safe surgical treatment for tumors of unclear origin. Removal of dedifferentiated liposarcoma with osteosarcomatous differentiation tumor with preservation of the lesion capsule without maintaining a margin of healthy tissue also allows for long-term cure. Precise immunohistochemical and molecular studies may have an impact on the effectiveness of further treatment and the prognosis of the patient. A patient after surgical treatment of liposarcoma requires constant outpatient follow-up for the reason of the high risk of local and distant recurrence.

Renal and perirenal abscesses are very rare in children. They can be present as an acute emergency condition or insidiously as a chronic disease. The diagnosis is not so obvious, and it is a big challenge, especially when it can simulate a kidney tumor. The treatment can be conservative, preferably with targeted antibiotics, or surgical, consisting primarily of drainage. This publication aims to present a clinical case in which both diagnosis and treatment were a big challenge for the entire treatment team. A 10-year-old male patient was admitted to the hospital because of mild abdominal pain and a temperature of 37.5 °C. The symptoms lasted for a week. In the computed tomography (CT), the lesion’s dimensions were 11.1 × 8.2 × 25 cm, and inflammation, abscess, cyst, and abdominal tumor have been suggested. The decision about surgical treatment was made. An enormous abscess near the right kidney was localized. The patient’s condition stabilized after surgery. Unfortunately, due to persistent purulent reservoirs, a second laparotomy was necessary. During the extensive diagnostic cystourethrography performed, vesicoureteral reflux was visualized. In conclusion, though a perinephric abscess is very rare in children, it should be taken into consideration in patients with non-specific abdominal symptoms. The imaging using ultrasound and CT scan with contrast enhancement is crucial to recognize and properly treat the condition. In terms of a small abscess, the only antimicrobial treatment using antibiotics of a broad spectrum can be considered. However, the drainage of an abscess, either percutaneous or open, should be used. For the large abscess, the open drainage seems to be a primary method of treatment. The importance of cooperation in a multidisciplinary team is crucial, as the diagnosis and treatment of underlying causes are essential.

The International Neuroblastoma Risk Group Staging System (INRGSS) is based on the age of patients and preoperative imaging, with attention paid to whether the primary tumor is affected by one or more of specific image-defined risk factors (IDRFs). This publication presents a 2.5-year-old boy with neuroblastoma who had an accidental ligation of the celiac trunk during tumor resection. The consequences of this complication were pancreatic and spleen ischemia and necrosis, ischemia, and perforation of the common bile duct, gallbladder, stomach, and duodenum. The aim of this publication was to highlight the great role of the radiologist in determining the indications for neuroblastoma tumor removal, especially with current vascular IDRFs, and to show how the radiologist’s insightful approach can save the patient from irreversible complications.

Melanocytic nevi, commonly known as moles, are benign skin lesions that often occur in children and adolescents. Overall, they are less common in children compared to adults. Understanding the diagnosis and management of melanocytic nevi and risk factors for melanoma development is crucial for their early detection and appropriate treatment. This paper presents children’s most common melanocytic nevi, including their epidemiology, morphology, diagnostic methods, and treatment.

Testicular and scrotal abnormalities can occur in children, adolescents, and adults. The lesions, often accompanied by pain and swelling/enlargement of the scrotum, can cause anxiety in patients and their parents. Regardless of age, proper diagnosis is based on adequate anamnesis and physical examination. Color Doppler ultrasound is the first-line test in the differential process of testicular and scrotal diseases. Testicular and scrotal lesions require differentiation for benign and malignant processes as well as therapeutic management, including urgent surgical intervention. The aim of this paper is to present the most common causes of testicular and scrotal abnormalities in pediatric and adult patients and to outline the symptoms and diagnostic and therapeutic management.

Background and Aim: Pediatric surgery requires high precision and safety due to children's unique anatomy and physiology. Innovations that enhance surgical precision, reduce operative time, and improve postoperative outcomes are invaluable. Indocyanine green (ICG), a near‐infrared fluorescent dye, has received significant attention for its potential to address these needs. The study aimed to describe applications of ICH in pediatric surgery in Poland, provide evidence to support integration of ICG into pediatric surgical practice and evaluate the safety and feasibility of ICG.Methods: Data were collected from the medical records of 136 patients undergoing surgical treatment in four leading pediatric surgical clinical centers in Poland. There are four main groups of surgical procedures: oncological, gastrointestinal, urological and lymphatic. Calculations were performed using Statistica 13 by TIBCO and PQStat v. 1.8.6.120 by PQStat Software. Additionally, descriptive statistics were performed.Results: The efficacy and safety of ICG were confirmed in the entire study group. No complications were reported with the use of the indocyanine green. Exhaustive descriptive statistics presented key information on the use of ICG for each of the studied groups.Conclusions: The study validates the efficacy and safety of ICG fluorescence imaging in pediatric surgery. By enhancing surgical precision and improving postoperative outcomes, ICG represents a significant advancement in pediatric surgical care. The establishment of standardized protocols and the emphasis on specialized training will be key to maximizing the benefits of ICG.