Athens, Greece (UroToday.com) Dr. Amlesh Seth gave an overview of the current treatment of renal cell carcinoma (RCC) with caval thrombus. Approximately 2-3% of all adult malignancies are RCC. Inferior vena cava (IVC) thrombus occurs in 4-10% of all RCCs. The thrombus can be localized to the renal vein, but can also reach up to the right atrium, without any involved lymph nodes or other systemic metastases.
When encountering an IVC thrombus as part of an RCC tumor, the workup of the patient should entail the following:
- Chest x-ray, liver function tests, ECG
- CT of the abdomen
- CT of the chest if there is suspicion for a level 4 thrombus reaching the heart
- Coronary angiography
- Doppler ultrasound the evening before the planned surgery
The surgical approach in this scenario can involve a midline, bilateral subcostal (Chevron), right thoracoabdominal, or long midline laparotomy / mid sternotomy surgical incision, according to the tumor thrombus level.
The first step once inside the abdomen should be to control the arterial supply of the kidney as early as possible. It is important to note that each kidney receives 10% of the cardiac output, and this increases significantly with a large renal tumor. There is also significant arteriovenous shunting that needs to be considered. The large renal tumor can result in venous obstruction, causing another vascular problem. Importantly, 25% of patients can have accessory renal arteries, which need to be found and controlled as well.
The tumor thrombus has distinct anatomic levels, as can be seen in Figure 1. These include the renal vein, infra-hepatic, intra-hepatic (>2 cm above and <2 cm below the confluence of the hepatic veins), supra-haptic, and intra-atrial.
Figure 1 – Tumor thrombus anatomic levels:
In infra-hepatic tumors, it is important to completely mobilize the tumor and leave it hanging on the IVC. It is important to control the IVC above and below the thrombus and control the opposite renal vein. Next, the lumbar veins in the field need to be ligated and once doing the actual cavotomy, it is imperative to keep it small. For left-sided tumors, arterial control of the right renal artery is required as well.
For intra-hepatic thrombus >2 cm below the hepatic vein confluence, the intra-hepatic IVC needs to be dissected. A well-defined plane needs to be developed between the IVC and the hepatic parenchyma. All tributaries from the liver into the anterior and lateral surface of the IVC need to be controlled. After this has been achieved, the same steps as for infra-hepatic thrombus need to be followed.
For intra-hepatic thrombus <2 cm below the hepatic vein confluence, complete mobilization of the liver is required. The IVC above the hepatic veins needs to be controlled as well. Lastly, cross-clamping of the IVC below the thrombus, opposite the renal vein, and using Pringle’s cross-clamping of portal structures.
In supra-hepatic thrombus, the intra-pericardial IVC needs to be controlled. For right-sided tumors, it is preferable to use a thoracoabdominal approach, while for left-sided tumors, a long midline laparotomy and mid sternotomy are better. If higher-level thrombus is present, the most commonly used technique is cold hypo-thermic circulatory arrest with exsanguination. The patient is put on cardio-pulmonary bypass and cooled to 18-20 degrees Celsius. The patient is then exsanguinated and the heart and lung machine is stopped. Blood supply to the central nervous system, coronary arterial supply, bronchial and upper limb arterial supply needs to be kept.
Lastly, when a distal bland thrombus is found (as opposed to a tumor thrombus), the IVC below the renal vein level needs to be ligated.
In conclusion, figure 2 summarizes the various treatment options according to the tumor thrombus level.
Figure 2 – Treatment of tumor thrombus in renal cell carcinoma:
Presented by: Amlesh Seth, MBBS, MS, MCH, Professor, Department of Urology, All India Institute Of Medical Sciences, India
Written by: Hanan Goldberg, MD, Urology Department, SUNY Upstate Medical University, Syracuse, New-York, USA @GoldbergHanan at the 39th Congress of the Société Internationale d'Urologie, SIU 2019, #SIUWorld #SIU2019, October 17-20, 2019, Athens, Greece