Successful interdisciplinary treatment of renal cell carcinoma with tumour thrombus into inferior vena cava using multimodal protocol and organ-extending R0 resection in rare horseshoe kidney and doubled right organ

Abstract

This is the first case ever reported showing a combination of renal cell carcinoma (RCC) with tumour thrombus into inferior vena cava (IVC), horseshoe kidney and doubled right kidney that was successfully treated. Even in advanced tumour lesions of the kidney, curative treatment is a feasible and safe option by using interdisciplinary cooperation and expertise. However, this requires an adequate diagnostic work-up to clarify resectability and optimal perioperative and postoperative care, and also advanced surgical skills exhausting all potential options for complete tumour resection in a centre of excellence. Achieving R0 resection with a reasonable risk-benefit ratio for the patient, which should be the primary aim, can distinctly improve survival chances as published cases in literature have indicated. RCC-derived IVC tumour thrombus as an extra-renal tumour manifestation by continuous intravascular tumour growth (also classified as secondary IVC tumour lesion) can be considered no serious contraindication to aim for curative surgery.

Background

We present a rare case of combined renal cell carcinoma (RCC) with inferior vena cava (IVC) tumour thrombus in a horseshoe kidney with doubled right organ. This case shows the successful interdisciplinary cooperation of urologist and vascular surgeons in a complex and advanced tumour disease.

Case presentation

A 64-year-old man was transferred to our institution after right transabdominal tumour nephrectomy in a regional hospital 15 days since diagnostic work-up had revealed a rare horseshoe kidney with simultaneous doubled right organ and ureter fissus (figure 1) and also an RCC at the right kidney. Patient’s medical history was unremarkable except arterial hypertension for years and bilateral inguinal hernia after former herniotomy on the right side. Apart from a palpable tumour mass in the right abdomen, there were no further signs and symptoms. The initial CT scan revealed a tumour lesion of the right kidney (diameter 11 cm) suspicious for infiltration of the right psoas muscle. It also showed enlarged lymph nodes at the para-aortic site (also increased in number) but no suspicion of metastases within organs such as liver, lung and bones.

Figure 1.

Preoperative ureteropyelography with doubled right renal pelvis and ureter fissus in a horseshoe kidney.

On admission, there was an incomplete RCC resection status indicated by R1 at the parenchymal transection site and R2 within the stump of the left renal vein, with remaining tumour manifestation (thrombus) within the IVC of a horseshoe kidney, as well as lymph node metastases in the former resection area, in particular, assessed by a postoperative control CT scan of the abdomen. Histopathological investigation had revealed a clear cell carcinoma up to 11 cm in diameter (tumour stage, pT3a pNx pMx L0 V1 G2).

Clinical examination revealed a patient in good physical condition with no abdominal wound complication after former surgical intervention. Prostate was enlarged with no further pathological finding. The following laboratory parameters were elevated: creatinine, 154 µmol/litre; platelet count, 639 gpt/litre.

Investigations

For planning of a surgical re-intervention, in particular for (i) appropriate re-staging of the current tumour manifestations, (ii) assessment of vascular involvement and (iii) short-term follow-up with regard to residual left kidney, residual tumour lesions and lymph nodes, an abdominal angiographic multi-slice CT scan was performed. It showed, in addition to the reported findings of the initial scan (see above):

necrosis at the renal parenchyma resection area,

retroperitoneal and interaortocaval lymphadenopathy (indicated by enlarged lymph nodes),

precise tumour site of the IVC thrombus—namely, proximally to the former confluence of the right renal vein up to the pancreas,

no tumour detection at the confluence of the hepatic veins

no hepatic or pulmonary metastases (figure 2A,B).

Figure 2.

CT: residual horseshoe kidney after right nephrectomy with a necrotic area at the isthmus region and inferior vena cava tumour thrombus in the coronar (A) and transversal scans (B).

Treatment

Complete resection of residual RCC tumour lesions was achieved by repeated renal parenchyma resection at the former transection site, with right adrenalectomy and radical extended lymphadenectomy, including cavotomy at the renal pedicle IVC segment under total clamping below the hepatic confluence, removal of tumour thrombus, plus partial resection of IVC wall (figure 4A), and alloplastic patch plasty (Vascu-Guard, Vascutek, Hamburg, Germany; length 6 cm) (figure 3A, B) using successfully the interdisciplinary cooperation of urologists and vascular surgeons.

Figure 4.

Macroscopic appearance of the resected inferior vena cava wall (*) with tumour thrombus (A). Histology of the tumour thrombus of the right renal vein stump (B). Histology of the tumour thrombus of the IVC showing tumour cells of the renal cell carcinoma embedded in fibrin (C) (H&E stain) and partial fibrous organisation of the thrombus (D) (Elastica van Gieson stain).

Figure 3.

Intraoperative situs after cavotomy showing endocaval tumour lesion (A) and removal of the tumour thrombus, partial wall resection and patch plasty (B) (Vascu-Guard, Vascutek, Hamburg, Germany).

Outcome and follow-up

Histopathological examination of the surgical specimen revealed vital and necrotic parts of clear cell RCC at the former renal isthmus with infiltration of the adherent surrounding connective-tissue but tumour-free lateral resection margins. In addition, a thrombosis of the right renal vein stump with initiated fibrotic transformation and small infiltrations of the RCC in the wall of the vein were found (figure 4B). The IVC thrombus was classified as tumour thrombus of the clear cell RCC (figure 4C,D). Resection margins of IVC and interaortocaval as well as sub-hepatic lymph nodes were tumour-free (figure 4). Final tumour stage was assessed as follows: pT3b pN0 cM0 L0 V1 R0 G2.

Postoperative hospital stay was uneventful (intensive care unit 1 day/hospital stay 11 days). Only, postoperative renal function was characterised by slightly elevated values of the following laboratory parameters: creatinine 146 µmol/litre; creatinine clearance 45 ml/min.

By 6 months postoperatively, control thoracoabdominal CT scan did not reveal any suspicion for a tumour re-manifestation. Currently, after a postoperative follow-up time period of 8 months, there are no further health problems.

Discussion

The described patient’s course documents the successful interdisciplinary care and inter-institutional cooperation between urology and vascular surgery in the treatment of a rare exemplary case. It was characterised by a complex and advanced tumour growth of a clear cell RCC with IVC tumour thrombus in a horseshoe kidney plus a doubled right organ. Such combination of an uncommon clinical manifestation of a malignant renal tumour lesion with two further rare anatomic variants or malformations of the kidney is presented for the first time in the available English-speaking literature.

Horseshoe kidneys can be characterised as an anatomic variant—in particular, an embryological fusion of the lower poles with usually non-malformated ureters.

RCC takes the third position of urological malignant tumour lesions and can originate from epithelial cells of renal parenchyma. The clear cell carcinoma is the most common type (70%) whereas other types are chromophile and chromophobe carcinomas as well as the rare neuro-endocrine carcinoma. RCC may comprise approximately 3–5% of all neoplastic tumour lesions. The incidence has been increasing; there is a peak during the seventh decade of age.

In spite of advances in systemic treatment of RCC, primary complete tumour resection with tumour-free resection margins, as confirmed by histological investigation, is the only curative treatment in the T1/T2 stage. However, the reported 5-year survival of 86–96% and 60–67%, respectively, in this specific group of patients suggests a dependence on tumour stage according to the UICC classification. Interestingly, in T3b RCC, characterised by an additional tumour thrombus into IVC, which can be found in 5–10% of all patients with RCC, survival rate is substantially lower ranging from 36–59%.

There have been only approximately 200 cases with tumour lesions in horseshoe kidney(s) published in the literature.^1–7 Combined with a doubled renal pelvis, it is extremely rare and only five cases have been published.^8–12

IVC tumour thrombus of the advanced T3 RCC, requiring partial wall resection of IVC and patch plasty, was classified as stage II by STAEHLER, characterised by IVC tumour thrombus site below the influx segment of hepatic veins.¹³

Since tumour thrombus was partially adherent to the inner wall of IVC, it was impossible to avoid partial resection of the wall of the IVC to finally achieve R0 resection.

The rare cases of IVC-associated tumour lesions do not allow collecting extensive experiences. Therefore, the material with good vascular-surgical results and excellent handling in our hands, such as Dacron, is favoured for the patch plasty. Alternative materials can also be used, such as (heparin-coated) ePTFE, Vascuguard and autogenous vein.

In BOWER’s classification, an infiltrating RCC with tumour thrombus into IVC is a specific and separate entity of an IVC-associated tumour lesion.¹⁴

For surgical strategy according to KULAYAT, tumour expansion of level 2 (middle segment) was assessed (from confluence of renal veins to hepatic veins).^15,16

In this context, complete resection of the tumour mass is the only efficient treatment of choice for cure and needs to be possibly achieved in the primary approach to avoid tumour fragmentation as happened. For curative intention, it needs to be included in planning surgery because, as mentioned above, 5–10% of all patients with RCC have already developed a continuous tumour infiltration of the anatomically neighboured IVC or even a tumour thrombus into IVC.¹⁷ In these cases, complete tumour resection comprising nephrectomy and resection of tumour-infiltrated parts or segments of the IVC or IVC-associated tumour thrombus has to be the basic aim of surgical treatment if there are no distant metastases. Since there are surgical options to achieve R0 resection status in case of an IVC tumour thrombus but no distant metastases, this seems to be of no significant disadvantage for patient’s prognosis,^18–20 although there is no extensive experience on this subject. Again, the aim is, despite primarily advanced tumour growth, to achieve macro- and microscopically complete resection to provide the patient’s best outcome.

In addition, such complex and advanced findings are manageable by modern (vascular) surgical techniques and materials.^15,16,21,22 A subsequent, secondary, additive (adjuvant) or alternative medication with tyrosine kinase inhibitors can be considered a further therapeutic option according to novel and recent reports.^23,24

Despite the overall successful outcome, the initial treatment has to be critically discussed because of the only non-complete primary resection leading to remaining and residual tumour lesions in situ, including the fact that preoperatively IVC-associated tumour thrombus had not been diagnosed. This might have worsened the patient’s mid- or long-term prognosis.

Therefore, a diagnostically complete and conclusive preoperative imaging is essential for the assessment of tumour extension, surgical options and planning the specific approach as well as prognosis.

Preferably in advanced, complex and complicated tumour manifestations, diagnostic and primary treatment should be performed in a centre of excellence to achieve an optimal outcome by interdisciplinary cooperation of operative disciplines and adequate perioperative intensive care.

In conclusion, achieving R0 resection with a reasonable risk-benefit ratio for the patient, which should be the primary aim, can distinctly improve survival chances.

Learning points

• This is the first report in literature of a rare case with co-incidence of RCC, IVC thrombus, horseshoe kidney and doubled right organ.

• In advanced tumour lesions of the kidney, aiming for resection is feasible and necessary for cure by primarily using an interdisciplinary cooperation in diagnostic work-up and treatment in a centre of excellence.

• To prevent any unexpected intraoperative events and needs, advanced surgical skills or special technical equipment (eg, off-pump cardiopulmonary bypass) are favoured, leading to the fact that further surgical disciplines, such as heart or vascular surgery, are included in planning and performing surgery as well as in postoperative care.

• Cure of RCC with IVC thrombus is possible by radical surgery, which includes complete tumour nephrectomy as well as resection of the tumour thrombus of the IVC. In case of thrombus adherence within the IVC or (rare) tumour infiltration of the IVC, resection or partial replacement of the IVC is necessary.