Create
Learn
Share

CC Jan 2016 Incidental renal mass

rename
echoecho's version from 2016-02-16 13:37

Section

Question Answer
Define incidental renal mass?designates a lesion (solid, cystic, inflammatory) identified on an imaging study not specifically looking for renal pathology
With the increasing number of scans ordered to evaluate for nephrolithiasis, abdominal pain and low back pain, providers are faced with the dilemma of whether or not an incidental renal mass requires further evaluation, as ___% to ___% of scans find renal lesions?13; 27
Most lesions are _____ _____ _____?benign simple cysts
List other possible nonmalignant etiologies?1) postinfectious inflammation 2) infarction 3) angiomyolipoma (macroscopic fat without calcifications) 4) oncocytomas 5) traumatic hematoma
True incidental renal masses are typically _______ (symptomatic vs. asymptomatic)?asymptomatic
On close questioning, patients may report vague symptoms of what?1) flank or abdominal pain 2) rarely, hematuria
Inflammatory lesions due to an infectious etiology almost always are accompanied by what symptoms?fever, chills or urinary irritation
Patients with ______ symptomatic lesions have worse prognoses than asymptomatic individuals?malignant
More than _____% of patients currently diagnosed with renal cell carcinoma are discovered via an incidental scan?70
What imaging study is the most appropriate test for evaluating an indeterminate renal mass (one that cannot be confidently diagnosed as benign or malignant at the time of discovery?thin-section, 3 phase CT abdominal scan with and without contrast
What is the rating by the American Colleg of Radiology (ACR) Appropriateness Criteria, although it also results in the highest exposure of radiation?9/9
*** Define enhancing solid masses seen after administration of contrast material during thin section 3-phase, renal CT?lesions having increased density ( > 15-20 Hounsfield units)
*** What % of the above patients (having enhancing solid masses identified during above imaging) have a malignancy and should be referred immediately for definitie therapy?80
What other imaging study is also appropriate (ACR rating 8/8)?multiphase magnetic resonance imaging (MRI) with and without gadolinium
Is MRI without contrast appropriate? Why or why not?no; because it can't characterize renal masses other than simple cysts and angiomyolipomas
Why are masses < 1.5 cm difficult to assess on CT?density and enhancement are difficult to determine in a mass that small
US exam may be prefereed as an initial test of choice in what patient types?1) when a patient can't lie flt for a CT scan 2) when there is impaired renal function 3) when there is an allergy to IV contrast
List the characteristics of a simple benign cyst found on ultrasound that does not require further radiologic evaluation?1)spherical or ovoid shape 2) absence of internal echoes 3) presence of a thin, smooth wall that is separate from the surrounding parenchyma 4) enhancement of the posterior wall
Who developed a system for classifying cystic renal masses?Bosniak
What imaging study guides management of above Bosniak classification of cystic renal masses?CT scan
What class have the highest risk of malignancy?class IV lesions
What variability using the system does exist?interobserver variability (one study showed that a second reader upgraded 16% of benign Class I/II lesions to Class III/IV
List the categories under Bosniak's classification of cystic renal masses?I, II, IIF, III, IV
List the radiographic features of Bosniak classification of cystic renal masses (category I)?1) simple benign cysts 2) smooth round or oval symmetric shape 3) unilocular with uniform density of water 4) have no perceptible wall 5) have no enhancement on radiographs taken after administration of contrast 6) density is < 20 HU when unenhanced
List the radiographic features of Bosniak classification of cystic renal masses (category II)?1) probable benign simple cysts < 3 cm that are mildly complex 2) few hairline thin septations < 2 mm 3) minimal calcification 4) infected cysts 5) high density cysts ( > 20 HU when unenhanced
List the radiographic features of Bosniak classification of cystic renal masses (category II F)?1) probable benign cysts > 3 cm with greater complexity 2) thicker calcifications 4) multiple septations with some thickening 5) no soft tissue component enhancement with contrast
List the radiographic features of Bosniak classification of cystic renal masses (category III)?1) complex cysts 2) malignant features such as thick, irregular calcifications, irregular borders, multilocular form, thickened or enhancing septa > 2 mm, uniform wall thickening or small, nonenhancing nodules
List the radiographic features of Bosniak classification of cystic renal masses (category IV)?1) malignant cystic masses 2) appearance of these lesion is due to necrosis and liquefaction of solid tumor or a tumor growing in the wall 3) heterogeneous with shaggy appearance, thickened walls or enhancing nodules
What is the likelihood of malignancy in Bosniak Classification of cystic renal masses (category I)?0-1.7%
What is the likelihood of malignancy in Bosniak Classification of cystic renal masses (category II)?0-14%
What is the likelihood of malignancy in Bosniak Classification of cystic renal masses (category II F)?18-25%
What is the likelihood of malignancy in Bosniak Classification of cystic renal masses (category III)?33-60%
What is the likelihood of malignancy in Bosniak Classification of cystic renal masses (category IV)?67-100%
What is the management of Bosniak Classification of cystic renal masses (category I)?Renal CT if symptomatic
What is the management of Bosniak Classification of cystic renal masses (category II)? Renal CT if symptomatic
What is the management of Bosniak Classification of cystic renal masses (category II F)?Renal CT at 6 and 12 months then annually for following 5 years
What is the management of Bosniak Classification of cystic renal masses (category III)?Renal CT/MRI and surgical evaluation
What is the management of Bosniak Classification of cystic renal masses (category IV)?Renal CT/MRI and surgical evaluation
*** Class I and II renal masses are treated as what?benign (no further imaging or evaluation is required
*** Class II F masses are often rescanned at ____ months, then yearly for ____ years?6; 5
Class IV renal masses are clearly what? and require what?malignant; surgical treatment
Class IV masses < 4 cm (clinical T1a) usually are treated with what?partial nephrectomy
Class IV masses > 4 cm (clinical T1b) usually are treated with what?radical nephrectomy
Classes III renal masses are more heterogenous group and who should interpret this group?a radiologist with experience interpreting renal CT scans
Class III lesions are suspicious for what (vast majority) and need what?a biopsy or minimally-invasive (lap) excision
If there is possible infection, what may be considered?needle biopsy
What imaging study may be used to further characterize class III lesions?MRI with and without contrast
What should be used to differentiate benign from malignant renal lesions?rate of growth
About what % of patients with malignant lesions < 4 cm have metastases at presentation?5
One study showed that ___% of malignant masses had no significant interval size change, nor did ___% of benign masses changes on serial exams?83%; 89%
*** Management in patients with limited life expectancy such as elderly patients and those with multiple comorbidities should be _______?individualized
*** Small, solid lesions (< 3-4 cm) that have a lower rate of high-grade histology than larger lesions may be managed using what?1) imaging surveillance OR 2) an active intervention like radiofrequency ablation or cryoablation
*** SUMMARY = Are true incidental renal masses typically asymptomatic or symptomatic?asymptomatic
*** SUMMARY = What imaging study is the most appropriate test for evaluating an indeterminate renal mass (one that can't be confidently diagnosed as benign or malignant at the time of discovery)?thin-section, 3-phase CT abdominal scan with and without contrast
*** SUMMARY = Renal lesions that meet criteria for simple benign cysts on ultrasound do not require further radiologic evaluation. Lists this criteria?1) spherical shape 2) ovoid shape 3) absence of internal echoes 4) presence of a thin, smooth wall that is separate from the surrounding parenchyma 5) enhancement of the posterior wall
memorize