Kidney tumors biopsy

Pancreas. Typically, the pancreas is surrounded by various organs like the stomach, liver, transverse colon, kidney, or major vessels. In particular, needle biopsy of small suspect masses in the pancreatic head is therefore usually regarded as technically sophisticated, and CT guidance preferred instead of ultrasound (Fig. 37.5). For differentiation of the tumor from surrounding normal parenchyma or inflammation, a contrast-enhanced CT scan obtained in an arterial phase should generally be performed prior to the intervention. The most common access route is from an anterior approach and often... 

Kidney. Biopsies of the kidney are rarely performed because they are often interpreted as hemorrhagic or inconclusive, and most solid renal masses are surgically removed. Exceptional indications for biopsy are suggested lymphoma and metastasis to the kidney from another primary tumor, since these conditions are usually not treated surgically. The usual access route under GT guidance is posterior or lateral while the renal hilum should be avoided. 

Most renal masses can be characterized with high accuracy by noninvasive imaging alone, and a sohd non-fat-containing or complex renal mass should be considered a renal cell carcinoma until proven otherwise. Metas-tases to the kidney are usually small and multifocal or perinephric. Lymphomatous involvement of the kidneys also usually occurs in the setting of disseminated disease and is characterized by typical CT patterns like multiple small masses, spread from retroperitoneal disease, diffuse infiltration, and perinephric encasement. In a study by Lechevallier et al. (2000), CT-guided renal biopsy of 63 patients had an overall accuracy of 89%. Biopsy material was not sufficient for analysis in 15 patients (21%). Unsuccessful biopsy was related to lesion size biopsy was unsuccessful in 11 of 30 tumors (37%) of 3 cm or less, versus 4 of 43 (9%) of tumors greater than 3 cm. 

Systemic symptoms may also occur, such as hypocal-caemia. Occasionally, patients may have hypertension from the tumor affecting the rennin-angioten-sin pathway. RCC metastases most commonly affect the spine, proximal long bone, pelvis, ribs, sternum, and skull [3, 22, 23]. Since the kidney is comprised of mostly blood vessels, RCC is normally a hyper-vascular tumor. RCC metastases usually mimic the primary tumor in vascularity, being hypervascular in 65%-75% of patients, and bleeding extensively (even audibly) after a simple biopsy [3,8]. 

Partial nephrectomy is sometimes considered in unilateral WT when the child has contralateral non-functioning kidney or associated renal disease or associated predisposing syndrome (SIOP 2001). Nevertheless, partial nephrectomy is contraindicated in unilateral multifocal tumors, central location, involvement of more than 1/3 of kidney, preoperative tumor rupture or biopsy, infiltration of extra-renal structures, intra-abdominal metastases or lymph nodes, thrombosis of RV or I VC, involvement of calyces or hematuria (SIOP 2001). 

Fig. 24.14. Juvenile renal cell carcinoma in a 9-year-old girl presenting with abdominal pain. Enhanced CT scan shows a non-specific heterogeneous tumor of the left kidney. Relative small tumor size and patient age are suggestive criteria for renal cell carcinoma and must lead to a diagnostic biopsy...

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