Perfusion Scanning's for Kidney Tumors
Condition: Kidney Cancer
MeSH terms: Kidney Neoplasms
Study type: Observational

Summary: 
      To investigate the ability of perfusion CT/US-scanning to facilitate recognition of different
      tumour sub-types in small renal masses less than 7 cm by non-invasive imagining technology.
    

Detailed description: 
      The number of diagnoses of renal cell carcinoma has increased over the past two decades
      because of the incidental detection of small renal tumours resulting from increased use of
      computed tomography [1,2]. There are distinct subtypes of renal cell carcinoma (RCC), and the
      biological aggressiveness and prognoses for these subtypes have been documented. Clear-cell
      RCC is the most common RCC subtype, followed by papillary RCC, chromophobe RCC and
      unclassified RCC. Collecting duct carcinoma is a rare and highly malignant type of RCC.
      Although most enhancing renal masses in adults are RCC, a significant percentage are benign
      (commonly oncocytoma), and these benign tumours cannot be distinguished from malignant
      tumours based on our standard imaging technology alone.

      Benign primary renal masses include simple renal cysts, psuedotumours, angiomyolipomas,
      oncocytomas, juxtaglomerular tumours, multilocular cystic nephromas, mesoblastic nephromas
      and papillary adenomas. In a recent surgical series of 228 patients who underwent partial or
      radical nephrectomy with lesions ≤4 cm, 26.3% were benign [3]. The relatively high percentage
      of patients with benign renal cortical neoplasms who undergo surgery highlights the
      importance of new diagnostic technology in avoiding over-treatment.

      Ultrasound (US) and CT scanning guided biopsy is the most commonly used method to diagnosis
      RCC. The sensitivity of biopsy for small masses (≤3 cm) is lower than for large masses [4].
      Sensitivity is limited by false-negative results, which are due to a failure to properly
      target a small mass or the presence of impossible-to-differentiate benign from malignant
      cells due to insufficient cells, morphological overlap or cellular heterogeneity. Non
      diagnostic biopsy is not necessary benign, as repeated biopsy reveals malignancy diagnosis in
      the majority[5]. There is no radiologic criteria consistent with oncocytoma because of a lack
      of sensitivity and specificity [6]. MR-scanning and CT-scanning are not feasible diagnostic
      methodologies for oncocytoma because of the possibility of overlapping results from
      oncocytoma and RCC [7].

      Hypotheses: To investigate the ability of perfusion CT/US-scanning to facilitate recognition
      of different tumour sub-types in small renal masses less than 7 cm by non-invasive imagining
      technology.

      Purpose: To recognize different subtype's renal tumor by non invasive scanning. Design: A
      descriptive study
    

Observational model: Cohort
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        the cohort will be selected from department of urology, Roskilde Hospital