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Date of last update: 10/09/2017.

Forum Name: Miscellaneous Nephrology Topics

Question: Mass Suspicious for Malignancy midpole of left kidney

 kmakifl - Thu Aug 19, 2010 7:41 pm

my symptoms beginning Saturday, was dark urine, no pain. Sunday clear urine, no pain. Monday bright red gross hematuria, no pain. Monday afternoon, pain between rib cage and pelvic area, gross hematuria and clear urine; no pain while urinating. Monday evening, pain increase with nausea and vomiting. Non-contrast CT indicates renal mass.

Tuesday, no pain and clear urine. Wednesday, pain and CT with and without contrast confirms enlarged left kidney and renal vein, no contrast in left kidney. This morning, MRI with and without contrast. left kidney has complex mass involving midpole of left kidney with heterogeneous enhancing character. 6h x 6w x 5.6 cm anterior - posterior dimension, mass suspicious for malignancy mid pole left kidney. Urologist does not believe bleeding is from mass.

GFR at 58 non-African, 71 African am, BUN @ 17 and creatinine @ 1.

Thanks for you advice.
 Dr.M.Aroon kamath - Sun Aug 29, 2010 4:36 am

User avatar Hi,
With the advent of the newer imaging techniques, an increasing number of renal asymptomatic renal 'masses' are being detected. Based on the size of these lesions, the fraction of solid renal masses that are likely to be benign are as follows.
< 1 cm - 46.3%
1 to < 2 cm - 22.4%
2 to < 3 cm - 22%
3 to < 4 cm - 19.9%
4 to < 5 cm - 9.9%
5 to < 6 cm - 13.0%.
(Frank I et al. (2003) Solid renal tumors: an analysis of pathological features related to tumor size. J Urol 170: 2217–2220).

Larger kidney masses (greater than 7cm or about 3.5 inches) are more commonly malignant tumors. Indeed, > 90% of these growths are likely to be malignant in nature.

Difficulty arises at times in differentiating "high attenuation" renal cysts (hyperdense or hemorrhagic) and renal cell carcinomas. High attenuation indicates that the a renal lesion that has an attenuation greater than that of simple fluid (ie, −20 to +20 Hounsfield units) on a single phase of enhancement CT(with only portal venous phase images). This dilemma may be sorted out by using additional imaging studies such as ultrasonography (US), multiphase CT, or magnetic resonance (MR) imaging. Internal heterogeneity of the lesion also favors a diagnosis of a renal cell carcinoma. Bleeding into a renal cyst is sometimes very difficult to exclude, as fresh blood clot has an attenuation of 60–80 HU. Your urologist, in all probability, would discuss with the radiologist before planning further management.
Best wishes!

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