A 65-year-old woman with no personal history of interest was admitted with a high fever of 1 week's duration with no apparent source, for which reason a thoracoabdominal CT scan was performed, showing a large mass (9x8x7 cm) in the right upper pole of the kidney, in close contact with the liver. She reported no other symptoms except pain and functional impotence in the left lower limb for months of evolution, followed up by the Neurosurgery Department and diagnosed, after CT scan of the spine and Nuclear Magnetic Resonance Imaging (NMR), with degenerative pathology, stenosis of the L4-L5 canal and spondyloarthrosis. She did not present constitutional syndrome or abdominal pain.

Physical examination revealed a soft and depressible abdomen, globular, without palpation of masses or megaliths. No pain on examination. Bilateral renal perfusion was negative.
Laboratory tests showed no alterations in biochemistry with liver profile, total proteins and calcium in normal range. Haemoglobin count was 9.4 g/dL and 22,500 leukocytes (N: 72.9%). Haemostasis without findings. Sterile blood cultures and urine cultures <10,000UFC/ml.
Broad-spectrum antibiotic and antipyretic treatment was started, despite which the patient presented daily febrile peaks with clinical repercussions in the form of asthenia.
In view of the CT findings, an MRI scan was performed, confirming a solid mass in the right upper pole measuring 14x10x10 cm in diameter, with great signal heterogeneity and necrosis inside. The lesion extends upwards towards the liver with signs of hepatic infiltration. The right renal vein and vena cava are free. There are retrocaval adenopathies, pleural effusion and diaphragmatic thickening.

Given the liver involvement, the case was discussed with the General and Digestive Surgery Department, who agreed to perform a multislice CT scan to determine more accurately the level of involvement of this organ and to plan the surgical intervention. A heterogeneous mass with a necrotic appearance and a maximum diameter of 11 cm was observed in the upper half of the right kidney with no plane of separation of the postero-superior segments of the right hepatic lobe, with contiguous involvement of the same.

Following renal embolisation, surgery was performed by means of supra- and infra-umbilical median laparotomy. Examination showed renal tumour infiltrating the liver (segment VII) and diaphragm, with pathological lymphadenopathies in the renal hilum and free peritoneal fluid with no evidence of peritoneal implants. Samples of peritoneal fluid were taken for culture, cytology and gram negative results. Right radical nephrectomy was performed, including en bloc the VII hepatic segment, right adrenal and portion of the diaphragm. Cholecystectomy and lymphadenectomy.
Pathological analysis revealed conventional type renal cell cancer of high cytological grade (Fuhrman grade 4), with foci of sarcomatoid transformation and extensive areas of tumour necrosis. Two satellite nodules on the peritoneal surface of the diaphragm and metastasis in a lymph node in the renal hilum. No involvement of the renal venous or excretory system or the adrenal gland. Stage pT4G3N1 according to UICC.
After a satisfactory postoperative period with a progressive decrease in leukocytosis, oral chemotherapy treatment with angiogenesis inhibitors was started. The second control CT scan performed two months after the operation showed right pleural effusion with basal and posterior pleural nodular lesions. The cytology of the pleural fluid was compatible with adenocarcinoma.