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Rarely Described Renal Malignancies Associated With Venous Tumor Thrombus

Background/Aim: Collecting duct carcinoma, epithelioid angiosarcoma and neuroendocrine/carcinoid tumor are uncommon renal malignancies, and their association with tumor thrombus extending into the inferior vena cava is extremely rare. Owing to the rarity of the above-mentioned malignancies and short follow-up of the cases published in the literature, the prognosis and clinical behavior of these tumors remains unclear. Up to date, the culprit of treatment is surgical management with radical nephrectomy, lymph node dissection, thrombectomy and vascular reconstruction if necessary. Patients and Methods: We herein describe in detail the first cases published of the above-mentioned renal malignancies associated with extensive inferior vena cava (IVC) thrombus, in which complex vascular reconstruction was performed. Results: Three male patients were identified as having collecting duct carcinoma, epithelioid angiosarcoma and neuroendocrine/carcinoid tumor with IVC involvement. Tumor thrombus levels were II, I and IIIc respectively. Patient ages were 42, 60 and 47 years and tumor sizes were 9.2, 10.9 and 3.7 cm correspondingly. Patient 2 underwent cavectomy, IVC replacement using polytetrafluoroethylene (Gore-Tex®) vascular graft and IVC filter deployment inside the graft. None of the patients developed any pulmonary emboli postoperatively. At the last follow-up, IVC graft for patient 2 remained patent. Conclusion: Owing to the rarity of the aforementioned malignancies and short follow-up of cases published in the literature, the prognosis and clinical behavior of these tumors remains unclear. Up to date, the culprit of treatment is surgical management with radical nephrectomy, lymph node dissection, thrombectomy and vascular reconstruction if necessary. Polytetrafluoroethylene (Gore-Tex) vascular grafts are an excellent and safe option for complex vascular reconstructions in patients with evidence of IVC invasion.