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Indeterminate Renal Mass

Variant: 1   Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US abdomen with IV contrast Usually Appropriate O
MRI abdomen without and with IV contrast Usually Appropriate O
CT abdomen without and with IV contrast Usually Appropriate ☢☢☢☢
US kidneys retroperitoneal May Be Appropriate O
MRI abdomen without IV contrast May Be Appropriate O
CT abdomen with IV contrast May Be Appropriate ☢☢☢
CT abdomen without IV contrast May Be Appropriate ☢☢☢
CTU without and with IV contrast May Be Appropriate ☢☢☢☢
Arteriography kidney Usually Not Appropriate ☢☢☢
Radiography intravenous urography Usually Not Appropriate ☢☢☢
Image-guided biopsy renal mass Usually Not Appropriate Varies
MRU without and with IV contrast Usually Not Appropriate O

Variant: 2   Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US abdomen with IV contrast Usually Appropriate O
US kidneys retroperitoneal Usually Appropriate O
MRI abdomen without IV contrast Usually Appropriate O
CT abdomen without IV contrast May Be Appropriate ☢☢☢
Arteriography kidney Usually Not Appropriate ☢☢☢
Radiography intravenous urography Usually Not Appropriate ☢☢☢
Image-guided biopsy renal mass Usually Not Appropriate Varies
MRI abdomen without and with IV contrast Usually Not Appropriate O
MRU without and with IV contrast Usually Not Appropriate O
CT abdomen with IV contrast Usually Not Appropriate ☢☢☢
CT abdomen without and with IV contrast Usually Not Appropriate ☢☢☢☢
CTU without and with IV contrast Usually Not Appropriate ☢☢☢☢

Variant: 3   Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
Procedure Appropriateness Category Relative Radiation Level
US abdomen with IV contrast Usually Appropriate O
MRI abdomen without and with IV contrast Usually Appropriate O
US kidneys retroperitoneal May Be Appropriate O
MRI abdomen without IV contrast May Be Appropriate O
CT abdomen without IV contrast May Be Appropriate ☢☢☢
Arteriography kidney Usually Not Appropriate ☢☢☢
Radiography intravenous urography Usually Not Appropriate ☢☢☢
Image-guided biopsy renal mass Usually Not Appropriate Varies
MRU without and with IV contrast Usually Not Appropriate O
CT abdomen with IV contrast Usually Not Appropriate ☢☢☢
CT abdomen without and with IV contrast Usually Not Appropriate ☢☢☢☢
CTU without and with IV contrast Usually Not Appropriate ☢☢☢☢

Panel Members
Summary of Literature Review
Introduction/Background
Special Imaging Considerations
Initial Imaging Definition

Initial imaging is defined as imaging at the beginning of the care episode for the medical condition defined by the variant. More than one procedure can be considered usually appropriate in the initial imaging evaluation when:

  • There are procedures that are equivalent alternatives (i.e., only one procedure will be ordered to provide the clinical information to effectively manage the patient’s care)

OR

  • There are complementary procedures (i.e., more than one procedure is ordered as a set or simultaneously wherein each procedure provides unique clinical information to effectively manage the patient’s care).
Discussion of Procedures by Variant
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
A. Arteriography Kidney
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
B. CT Abdomen
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
C. CTU
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
D. Image-Guided Biopsy Adrenal Gland
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
E. MRI Abdomen
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
F. MRU
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
G. Radiography Intravenous Urography
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
H. US Abdomen with IV Contrast
Variant 1: Indeterminate renal mass. No contraindication to either iodinated CT contrast or gadolinium-based MR intravenous contrast. Initial imaging.
I. US Kidneys Retroperitoneal
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
A. Arteriography Kidney
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
B. CT Abdomen
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
C. CTU
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
D. Image-Guided Biopsy Adrenal Gland
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
E. MRI Abdomen
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
F. MRU
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
G. Radiography Intravenous Urography
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
H. US Abdomen with IV Contrast
Variant 2: Indeterminate renal mass. Contraindication to both iodinated CT and gadolinium-based MR intravenous contrast. Initial imaging.
I. US Kidneys Retroperitoneal
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
A. Arteriography Kidney
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
B. CT Abdomen
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
C. CTU
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
D. Image-Guided Biopsy Adrenal Gland
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
E. MRI Abdomen
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
F. MRU
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
G. Radiography Intravenous Urography
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
H. US Abdomen with IV Contrast
Variant 3: Indeterminate renal mass. Contraindication only to iodinated CT intravenous contrast. Initial imaging.
I. US Kidneys Retroperitoneal
Summary of Recommendations
Supporting Documents

The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.

For additional information on the Appropriateness Criteria methodology and other supporting documents, please go to the ACR website at https://www.acr.org/Clinical-Resources/Clinical-Tools-and-Reference/Appropriateness-Criteria.

Gender Equality and Inclusivity Clause
The ACR acknowledges the limitations in applying inclusive language when citing research studies that predates the use of the current understanding of language inclusive of diversity in sex, intersex, gender, and gender-diverse people. The data variables regarding sex and gender used in the cited literature will not be changed. However, this guideline will use the terminology and definitions as proposed by the National Institutes of Health.
Appropriateness Category Names and Definitions

Appropriateness Category Name

Appropriateness Rating

Appropriateness Category Definition

Usually Appropriate

7, 8, or 9

The imaging procedure or treatment is indicated in the specified clinical scenarios at a favorable risk-benefit ratio for patients.

May Be Appropriate

4, 5, or 6

The imaging procedure or treatment may be indicated in the specified clinical scenarios as an alternative to imaging procedures or treatments with a more favorable risk-benefit ratio, or the risk-benefit ratio for patients is equivocal.

May Be Appropriate (Disagreement)

5

The individual ratings are too dispersed from the panel median. The different label provides transparency regarding the panel’s recommendation. “May be appropriate” is the rating category and a rating of 5 is assigned.

Usually Not Appropriate

1, 2, or 3

The imaging procedure or treatment is unlikely to be indicated in the specified clinical scenarios, or the risk-benefit ratio for patients is likely to be unfavorable.
Relative Radiation Level Information
References
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Disclaimer

The ACR Committee on Appropriateness Criteria and its expert panels have developed criteria for determining appropriate imaging examinations for diagnosis and treatment of specified medical condition(s). These criteria are intended to guide radiologists, radiation oncologists and referring physicians in making decisions regarding radiologic imaging and treatment. Generally, the complexity and severity of a patient’s clinical condition should dictate the selection of appropriate imaging procedures or treatments. Only those examinations generally used for evaluation of the patient’s condition are ranked.  Other imaging studies necessary to evaluate other co-existent diseases or other medical consequences of this condition are not considered in this document. The availability of equipment or personnel may influence the selection of appropriate imaging procedures or treatments. Imaging techniques classified as investigational by the FDA have not been considered in developing these criteria; however, study of new equipment and applications should be encouraged. The ultimate decision regarding the appropriateness of any specific radiologic examination or treatment must be made by the referring physician and radiologist in light of all the circumstances presented in an individual examination.