Baylor University Medical Center Proceedings July 2017 - 328

Figure 2. MRI of the abdomen and pelvis showing a renal mass (arrow) in the
right kidney, as seen on (a) cross-section and (b) coronal section.

A multidisciplinary team recommended right nephrectomy
as an option to both exclude malignancy and remove the source
of hematuria. Right nephrectomy was performed successfully,
with no complications. The renal tissue sent for biopsy showed
a 7 cm mass extending into the renal pelvis. The tumor was
T2N0M0, grade 2, clear cell RCC. The surgery was curative
for the patient's tumor stage, and the patient was successfully
anticoagulated, with no further hematuria during the hospital
stay and following outpatient visits.
DISCUSSION
RCC is the most common type of kidney cancer in adults,
responsible for approximately 90% to 95% of cases. Clear cell
carcinoma is the most common type, representing about 70% of
all RCC (2). Other neoplasms are transitional cell carcinoma of
the renal pelvis, sarcoma, lymphoma, and Wilm's tumor. In an
early stage, RCC presents mostly with nonspeciﬁc symptoms such
as anorexia, tiredness, weight loss, or fever of unknown origin
(3)-making early diagnosis diﬃcult. The classic clinical triad of
hematuria, ﬂank pain, and a palpable ﬂank mass occurs in only
5% to 10% of cases and often indicates a more advanced stage
of the disease (4). Volpe et al proposed that the RCC incidence
has increased mainly due to the widespread use of cross-sectional
328

imaging; most renal tumors are detected incidentally as small,
asymptomatic masses. This study indicated an incidental detection rate of approximately 48% to 66%, while that rate was only
7% to 13% in the 1970s (5). Most renal lesions are benign simple
cysts, requiring no further workup. However, any solid renal mass
or mixed solid and cystic mass should be considered malignant
until proven otherwise and warrants further evaluation (6).
The standard evaluation of patients with suspected RCC
includes urinalysis with cytology, chest x-ray, and CT scan of
the abdomen and pelvis. RCC is generally a vascular tumor,
and angiography was a common investigation to assess vascularity preoperatively. However, angiography is not routinely used
anymore due to the availability of less-invasive options such as
spiral CT scan or dynamic magnetic resonance angiography.
The combination of renal ultrasound and CT scan is more
sensitive for the diagnosis and gives suﬃcient information for
surgical intervention (7, 8). Furthermore, the diagnostic and
staging value of angiography is limited compared to CT scan.
Angiography still retains its usefulness in exceptional situations
where interventional arteriography needs to be done, such as
for acute hemorrhage or embolization of potentially bleeding
tumors (8). MRI as a diagnostic tool is sometimes required
when indeterminate lesions are located or when a hyperattenuating renal mass is seen on CT scan (9, 10), as was the case in
our patient. This case should raise the level of awareness of the
possibility of false-negative results of renal ultrasound or CT
scan that warrants an MRI.
For the diagnosis of RCC, an image-guided renal mass
biopsy is safe, reliable, and accurate. It changes clinical management in many cases by avoiding nephrectomy or other surgical options (11). Insuﬃcient tissue size and sampling error
along with smaller masses and masses with internal necrosis
have been implicated in false-negative biopsy results (12). In
our patient, it was concluded that due to the central necrosis
and location of the mass, it was technically diﬃcult to take
adequate biopsy samples, which resulted in the false-negative
biopsy results that necessitated a nephrectomy due to the high
suspicion of malignancy.
Anticoagulation on currently recommended therapeutic
levels rarely causes hematuria, and further workup, including
MRI, appears warranted for persistent hematuria, even if renal
ultrasound and CT scan are both negative for a renal mass.
1. Davis R, Jones JS, Barocas DA, Castle EP, Lang EK, Leveillee RJ,
Messing EM, Miller SD, Peterson AC, Turk TM, Weitzel W; American Urological Association. Diagnosis, evaluation and follow-up of
asymptomatic microhematuria (AMH) in adults: AUA guideline. J Urol
2012;188(6 Suppl):2473-2481.
2. Cheville JC, Lohse CM, Zincke H, Weaver AL, Blute ML. Comparisons
of outcome and prognostic features among histologic subtypes of renal
cell carcinoma. Am J Surg Pathol 2003;27(5):612-624.
3. Choyke PL, Amis ES Jr, Bigongiari LR, Bluth EI, Bush WH Jr, Fritzsche
P, Holder L, Newhouse JH, Sandler CM, Segal AJ, Resnick MI, Rutsky
EA. Renal cell carcinoma staging. ACR appropriateness criteria. Radiology
2000;215(Suppl):721-725.
4. Luciani LG, Cestari R, Tallarigo C. Incidental renal cell carcinoma-age
and stage characterization and clinical implications: study of 1092 patients
(1982-1997). Urology 2000;56(1):58-62.

Baylor University Medical Center Proceedings

Volume 30, Number 3

Table of Contents for the Digital Edition of Baylor University Medical Center Proceedings July 2017