Case presentation
A 66-year-old female with a past medical history of hypertension, hyperlipidemia, hypothyroidism initially presented to the outpatient clinic with complaints of fatigue, generalized weakness, and unintentional weight loss of 10 pounds over three months. She was found to have anemia, and iron with vitamin D supplements was started. The patient was noted to have worsening of her symptoms with nausea, abdominal/flank pain. She also reported insomnia, bilateral pedal edema, loss of appetite, abdominal bloating, and abdominal fullness despite small portions of food. Colonoscopy was done, which was unremarkable.
A computed tomography (CT) scan of the abdomen and pelvis with oral and intravenous (IV) contrast showed large complex mixed attenuation partly solid and cystic mass, occupying the majority of mid to lower half of the left kidney measuring up to 11.6 cm into 10.7 cm in trans-axial dimension and up to 10.2 cm craniocaudal as shown in (Figure 1A). There was a contiguous extension of this mass-like structure into the renal hilum and across the left renal vein with a marked expansion of the left renal vein to approximately 3.5 cm in diameter with continued extension into the massively dilated inferior vena cava measuring up to 4.7 cm in diameter. Within the inferior vena cava, there was a filling defect tracking superiorly to the cavo-atrial junction, partially protruding into the right atrium and showing extension into the right hepatic vein. There was a hypodensity in the distal inferior vena cava progress to bilateral common iliac veins and external iliac veins (Figure 1B). A significant enlargement of the azygous vein, likely representing a collateral blood flow, was also noted. However, there was also a patent periphery to the inferior vena cava, probably representing venous flow around the tumor tissue itself. Associated hepatic congestion, venous collateral formation, ascites, and edema were also found on imaging (Figure 1A).
Physical examination was remarkable for tachycardia to 112 beats per minute, relative hypotension with a blood pressure of 94/52 mm of Hg, abdominal distension, left-sided abdominal pain, flank tenderness with fullness, and a palpable mass. Laboratory parameters were within normal range.
The patient was started on intravenous heparin infusion due to a high risk of pulmonary embolism and transferred to the intensive care unit (ICU) for close monitoring. The oncology, interventional radiology (IR), cardiology, and surgery consults were requested. An echocardiogram of the heart showed a left ventricular ejection fraction of 71%. The right atrial cavity was normal in size. A mass was protruding into the right atrium, measuring up to 2.8 cm into 3.1 cm extending into the right atrium from the inferior vena cava (Figure 2). Ultrasound-guided paracentesis was done, and fluid was negative for malignant cells. Chest X-Ray (CXR) showed normal cardiac shadow with small bilateral pleural effusions. Image-guided biopsy of the left renal mass was done, and histopathology showed renal cell carcinoma favoring clear cell type with strong affinity for cluster of differentiation-10 (CD10), cytokeratin-7 (CK7), and Vimentin (Figure 3). The tumor was categorized as left-sided renal cell carcinoma stage III (cT3cN0M0) by an Oncologist. Treatment began with a long-term therapeutic dose of lovenox and dual immunotherapy with ipilimumab and nivolumab. She was not a candidate for surgical and interventional radiology (IR) guided interventions due to hepatic vein thrombus and the extensive nature of thrombus.