Diagnostic dilemmas. Rare case of renal angiosarcoma

Abstract

Introduction. Renal hemangioma is an uncommon benign tumor that poses challenges in differential diagnosis as renal cancer is sometimes misdiagnosed as this condition. Primary renal angiosarcoma (RA) is an exceedingly rare and highly aggressive neoplasm, known for its high histological similarity to hemangioma. Case description. A 58-year-old male with BMI- 43 kg/m2, presented with persistent dull pain in the right side of the waist region. A pelvic CT scan revealed an abnormal mass in the right kidney measuring 20,5 x 17,2 x 15,4 cm suggesting renal cell carcinoma. Nephrectomy was performed. Postoperative histological analysis confirmed the diagnosis of renal hemangioma. Three months after the procedure, the patient reported weight loss of 15 kg per 6 weeks with recurrent abdominal and right pain. The blood test demonstrated anemia. A follow-up CT scan revealed ascites, and multiple metastatic lesions in the lungs, liver, and peritoneum. The previous histological sample was re-evaluated due to suspicion of malignancy. Based on the findings of the CT scan and the histological examination, the diagnosis of renal angiosarcoma was confirmed. Preoperatively, approximately three liters of ascitic fluid were drained and a diagnostic laparoscopy was performed. The diagnostic surgery revealed active bleeding from the greater omentum, liver, and mesentery. The surgical treatment option was rejected. Four days after initiating conservative treatment, the patient died. Summary. Primary RA is an exceptionally rare tumor prone to misdiagnosis. The diagnosis of RA heavily relies on the use of immunohistochemistry. Conclusions. The treatment of choice for RA typically involves radical nephrectomy with adjuvant therapy such as radiation and chemotherapy. Despite the initial treatment strategies, challenges in subsequent management of the condition remain unresolved. Due to its rarity, there is a lack of standardized management protocols for RA.