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Benign Renal Tumors

Vitaly Margulis; Jose A. Karam; Surena F. Matin; Christopher G. Wood

Questions

1.The most accurate imaging study to characterize a renal mass is:

a.intravenous pyelography.

b.ultrasonography.

c.computed tomography (CT) with and without contrast enhancement.

d.magnetic resonance imaging (MRI).

e.renal arteriography.

2.A hyperdense renal cyst may also be termed a:

a.probable malignancy.

b.Bosniak II cyst.

c.Bosniak III cyst.

d.Bosniak IV cyst.

e.probable angiomyolipoma.

3.The primary indication for fine-needle aspiration of a renal mass is which suspected clinical diagnosis?

a.Renal cell carcinoma

b.Renal oncocytoma

c.Renal adenoma

d.Renal metastasis

e.Renal angiomyolipoma

4.All of the following statements are TRUE about renal cysts EXCEPT:

a.They are the most common benign renal lesions found in the kidney.

b.They are best characterized using the Bosniak criteria to assess risk that the patient harbors a malignancy.

c.They are best imaged using ultrasound to allow classification with the Bosniak criteria.

d.They can harbor internal septa, calcifications, and internal debris and still be considered benign according to the Bosniak classification.

e.They rarely require treatment.

5.Which of the following is TRUE about renal adenoma?

a.There is uniform agreement regarding the clinical and pathologic classification of renal adenoma.

b.Recent studies suggest that renal adenoma may be a premalignant precursor of papillary renal cell carcinoma (RCC).

c.They are most common in young females.

d.They can be high grade or low grade, as long as they are smaller than 3 cm.

e.They are usually of clear cell histology but can also be found with chromophobe and papillary cells.

6.A diagnosis of renal adenoma:

a.can be made primarily on the basis of histologic criteria.

b.can be rendered only if tumor is smaller than 1 cm.

c.is commonly made at autopsy.

d.requires specific immunohistochemical staining.

e.can be confirmed by electron microscopy.

7.A healthy 62-year-old man is scheduled to undergo surgery for a 3.0-cm enhancing renal mass; CT shows it to be interpolar, exophytic, and with a central stellate scar. Which of the following best describes the most appropriate surgical strategy?

a.A radical nephrectomy with adrenalectomy

b.A radical nephrectomy without adrenalectomy

c.Renal exploration with biopsy and intraoperative frozen section analysis determining radical versus partial nephrectomy

d.Renal exploration and partial nephrectomy with intraoperative frozen section analysis of histology (if malignant, a radical nephrectomy)

e.Partial nephrectomy

8.A 48-year-old woman with a history of seizure disorder presents with recurrent gross hematuria and left flank pain. Abdominal CT shows a large left perinephric hematoma associated with a 3.0-cm left renal angiomyolipoma. There are also multiple right renal angiomyolipomas ranging in size from 1.5 to 6.5 cm. The next best step in management of the left renal lesion is:

a.selective embolization.

b.radical nephrectomy.

c.observation.

d.partial nephrectomy.

e.laparoscopic exposure and renal cryoablation.

9.Which of the following statements is TRUE regarding multiloculated cystic nephromas?

a.They are complex cystic lesions that are typically classified as Bosniak II.

b.They are malignant 2% to 5% of the time.

c.They are more common in men than in women.

d.They are characterized by bimodal age distribution.

e.They are readily differentiated from RCC on the basis of appropriate

imaging studies.

.Metanephric adenoma is differentiated from RCC based on all the following features EXCEPT:

a.female predominance.

b.benign clinical course.

c.specific pattern on immunostain marker panel.

d.characteristic appearance on MRI.

e.peak incidence in the fifth decade of life.

.Which of the following would be considered diagnostic for renal angiomyolipoma?

a.Hyperechoic pattern on ultrasonography

b.Enhancement of more than 30 Hounsfield units (HU) on CT

c.Small area of less than − 20 HU on nonenhanced CT

d.Aneurysmal changes on renal arteriogram

e.Positive signal on T2-weighted images of MRI

.Which of the following features is typically required for the diagnosis of renal adenoma in a clinical setting?

a.Tumor size smaller than 3 cm

b.Low to moderate grade

c.Papillary architecture

d.Nonconventional histology

e.Noncentral location

.Which of the following tumors is most likely to be a malignant RCC? a. A 2.5-cm hyperechoic complex cyst, with no enhancement after

intravenous administration of a contrast agent

b.A 6.0-cm complex cyst with four thin septa

c.A 5.0-cm cyst with thin, curvilinear calcification

d.An 11-cm cyst with water density and a homogeneous nature

e.A 3.0-cm tumor with fat associated with calcification

.A reliable finding for the diagnosis of renal oncocytoma is:

a.trisomy of chromosomes 7 and 17.

b.a central, stellate scar on CT.

c.a spoke-wheel pattern on renal angiography.

d.multiple mitochondria on electron microscopy.

e.a hypervascular pattern.

.A distinctive finding for renal angiomyolipoma is:

a.positive staining for vimentin.

b.a unique cytokeratin expression pattern.

c.positive staining for human melanoma black-45.

d.multiple microsomes on electron microscopy.

e.occasional aneuploidy.

.All of the following statements accurately describe mixed epithelial and stromal tumors of the kidney EXCEPT:

a.There is a female predilection.

b.They are associated with estrogen replacement therapy in women or with androgen ablation therapy in men.

c.Radiologic diagnostic criteria exist for reliable differentiation from RCC.

d.Nephron sparing with partial nephrectomy when technically feasible is appropriate.

e.A benign clinical course is expected.

.A 44-year-old man undergoes left laparoscopic partial nephrectomy for a 2-cm exophytic renal mass. Final pathologic review reveals intersecting fascicles of smooth muscle with no evidence of hypercellularity, pleomorphism, or mitotic activity. Surgical margins are negative. The next step in management is:

a.complete radical nephrectomy.

b.adjuvant chemotherapy.

c.adjuvant targeted therapy.

d.observation.

e.retroperitoneal external-beam radiation therapy.