**4. Other techniques**

per continuitatem, but most likely it is a sign of haematogenous metastasis with poor prog‐ nosis. On the other side the safety of imaging by using CT is at 97%. The likelihood of adre‐ nal metastasis in small T1 tumours is less than 1% [22]. After Robson in the 1960s described a survival benefit for patients that had a standard adrenalectomy [5], were not detected in subsequent studies [23]. The indication for removal of the adrenal gland is given in case of a very large renal tumour, an upper pole tumour and a suspected metastasis in the adrenal

Lymphadenectomy: For a long time conducting a regional lymphadenectomy (paraaortic/ paracaval) was an important part of the nephrectomy. The improved survival times when performing a lymphadenectomy were proven in part by the work of Robson. Especially in view of conversion of patients to small asymptomatic renal tumours, the removal of the ipsi‐ lateral lymph nodes is critical discussed similarly to the adrenalectomy. Though diagnosti‐ cally useful, the value of the hilar ipsilateral lymphadenectomy due to few studies regarding their prognostic significance remains unclear. The therapeutic benefit has not been proven. Interestingly in autopsy studies it was proven that the result of lymph node metastasis usu‐

Renal vein thrombus and vena cava thrombus: A special feature of the renal cell carcinoma is the tendency of ingrowth into the venous system. A tumour thrombus in the vena cava is found in about 4-10% of all cases, a tumour thrombus with growth up into the right atrium in 0.4% of all cases. Surgical removal of the thrombus should be sought in principle. The sur‐ gical procedure must be scheduled in this case depending on the extent of the thrombus.

Renal vein thrombi are removed by clamping the junction into the vena cava, thrombi of the vena cava below the diaphragm by a cavotomy. If there is an expansion beyond the hepatic hilum the use of a heart-lung machine is necessary. If there is an expansion to the right atrium the use of extracorporal circulation is required. An important aspect in the planning and implementation of these procedures is the interdisciplinary collaboration be‐ tween urologists and cardiac surgeons. The prognosis of patients with a tumour throm‐ bus after a successfully carried out surgery is not dependent on the size and extent of the thrombus, but the metastasis stage. After thrombectomy in a non-metastastic stage 5-year tumour specific survival rates up to nearly 70% can be achieved [24]. However almost half of all patients with an extensive vena cava thrombus at diagnosis show lymphatic or hae‐

Bilateral renal tumours: The incidence of synchronous bilateral renal tumours is at 1.6-6%. In principle a two-stage procedure is desirable, where initially the smaller and unifocal tumour can be treated in terms of a partial nephrectomy, with the aim to avoid dialysis in case a

gland (preoperative imaging studies or intraoperative finding).

ally shows an occult distant metastasis.

80 Renal Tumor

Level I:Infiltration of the renal vein

matogenous metastasis.

Level II:Infiltration of the infrahepatic vena cava Level III:Infiltration of the intrahepatic vena cava Level IV:Infiltration of the suprahepatic vena cava

subsequent contralateral nephrectomy is required.

Energy ablative therapy: The energy ablative method is based on tissue destruction by using cold or heat. Especially cryoablation (CA) and radiofrequency ablation (RFA) are to be men‐ tioned. There are percutaneous and laparoscopic techniques available. Essentially the indi‐ cation for performing the energy ablative method is limited to palliative situations or as an alternative for high-risk patients with small, conveniently located renal tumours. Potential benefits represent mainly the reduced morbidity and the possibility of treating multimorbid patients in an outpatient setting. The problem is, among other things, the increased risk of local recurrence [25].

LESS/NOTES: After establishing laparoscopic and robot-supported methods now further developments of the methodology in terms of a reduction of the required trocars (LESS = Laparoscopic Single Site Surgery) and the use of so-called "natural orifices" (NOTES = Natu‐ ral Orifice Translumenal Endoscopic Surgery) take place. Concerning this matter so far how‐ ever there are only casuistics and small case series available.
