Incidental clear-cell renal cell carcinoma with postop complication

Renal cell carcinoma (RCC) is thea malignancy of the renal tubular epithelium; with almost 50% of cases being incidentally discovered. RCC comprises about 2-3% of all malignancies and about 85% of all solid renal tumours. 2% of RCC cases are bilateral and 16-25% of cases are multi-centricmulticentric (in the same kidney). The usual age of presentation is 50 to 70 years and maleswith a male to femalesfemale ratio of affection is 2:1. Lesions usually arise in the renal poles (upper more than lower) and they appear as exophytic mass(s(es) that altersalter the renal contour. Most lesions are solid and of soft tissue density that is hyper-densehyperdense, iso-denseisodense or hypo-densehypodense to renal tissue, yet it may show haemorrhage, necrosis, fatty or fat and may be cysticcystic changes. It rarely calcifies (less than 10%) but the combination of fat and calcification suggests RCC rather than an angiomyolipoma.

The histopathological types of RCCs are: (1) Clear cell 70-80%, (2) Chromophil cell (papillary) 10-15%, (3) Granular cell 7%, (4) Chromophobe cell 5%, and (5) Spindle cell (sarcomatoid) 1-1.5%. Metastases may affect the lungs, liver, bone, adrenal glands, other kidney and brain. It has some association with von Hippel-Lindau * disease and tuberous sclerosis. TheAn RCC is asymptomatic in many cases and presentation with the classic triad of grossfrank haematuria, flank pain and palpable mass appears in less than 10<10% of cases ^{1 2,2}.

Multi-phasicMultiphasic CT is the best imaging tool to depict RCCs. This includes a pre-contrastprecontrast phase, arterial phase (15 secondss), cotico-medullarycorticomedullary phase (60 secondss), nephrgarphicnephrographic phase (&gt; 80 seconds;80 s) and excretory or pyelographic phase (2 to 5 minutes). The RCC lesions appearappears as an enhancing lesionslesion (increase of more than 20 HU to pre contrastcf. precontrast density) being hyper-densehyperdense to renal parenchyma in both nephrographic and pyelographic phases ¹ ²^1,2. Seldom Seldomly the lesion appears hypo-vascularis hypovascular (usually those of the papillary cell type) which may be mistaken for cysts ina cyst on all imaging tools)modalities ¹.

Lesions may infiltrate the renal vein or the calyces (where it may be mistaken for transitional cell carcinoma) and they may infiltrate surrounding muscles, diaphragm, colon as well as the IVC, liver, or right atrium in right sided lesions and pancreas, or spleen (in left sided lesions) ^{1 2,2}.

Although radical nephrectomy was considered for years the optimal treatment option, the results of numerous studies have demonstrated almost equivalent survival rates for patients who underwent radical nephrectomy and those who underwentvs. partial nephrectomy (or nephron sparing-sparing surgery) for small renal neoplasms so. Thus elective partial nephrectomy is now a valid treatment approach ^{1 2 4,2,4}. Partial nephrectomy or ablation (either by cryocryotherapy, radio-frequencyradiofrequency or microwaves) may be considered in lesions of small size and no extra renalextrarenal spread ^{1 2,2}. There is a limited role of chemotherapy and radiotherapy ¹. Now, partial nephrectomy and radical nephrectomy can both be carried out either by open or laparoscopic approaches ².

Vermooten back in 1950 was the first to suggest that localized RCC could successfully be excised while leaving a surrounding area of normal renal parenchyma ⁷⁶.

Common imaging findingfindings after surgery are: kidney displacement (posterior more than anterior), peri-nephricperinephric fat stranding, parenchymal defect, non-fat-containing post-operativepostoperative collection fat. Fat stranding is seen more inwith an open than in laparoscopic route. Collections are seen more in laparoscopic rather than open route, yet they resolve more rapidly with the open route. Occurrence and resolution of collection are not affected by age, sex, pre-operativepreoperative lesion size or location ³.

Changes like posterior kidney displacement and peri-nephricperinephric fat strands (when seen in imaging) were mentioned by some as a provemay provide evidence of previous renal surgery. Fatty packing done by the surgeon into the renal cortical defect afterpost partial nephrectomy may be mistaken afterwardslater for angiomyolipoma, and other haemostatic materials used in operation may show airgas bubbles and be mistaken for abscess ⁴.

Images revealed a few mm radio dense middle domainradiodense interpolar left renal stone.

An incidentally discovered 8 cm solid soft tissue density mass lesion is seen bulging from the upper pole of the right kidney. The right adrenal gland could beis clearly depicted. This mass shows a few small foci of calcification.

Images revealedreveal a few mm radio dense middle domaininterpolar left renal stone (green arrow).

An incidentally discovered 8 cm solid soft tissue density mass lesion is seen bulging from the upper pole of the right kidney. The right adrenal gland could beis clearly depicted (blue arrows). This mass shows a few small foci of calcification (red arrows).

Images revealed an upper pole right renal mass lesion showing low T1 signal, high T2 signal, and heterogeneous contrast enhancement with non enhancing-enhancing areas that likely represent breaking downnecrosis.  

An oval shaped encapsulated solid mass of about 7.5 X 5cmx 5 cm size.

On cut section, it showed heterogeneous appearance of mainly light yellow colour with multiple multiple areas of haemorrhage and necrosis.

There was no invasion of the renal capsule.

There is a 5 Xx 6 Xx 5 cm post-operativepostoperative fluid collection with peripheral enhancement seen posterior to the right kidney. This was aspirated under ultrasonographic guidance, culture and sensitivity tests were done and proper antibioticappropriate antibiotics were given.

A 1.5 cm left lower lobe lung nodule is newly developed.