In a 66‑year‑old woman, does the MRI demonstrate a 2.4 cm nodule in the left kidney, and what is the appropriate management?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: February 5, 2026View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

No 2.4 cm Nodule on Left Kidney Identified

The MRI report explicitly states "No focal lesions in the left kidney," meaning there is no 2.4 cm nodule present in the left kidney. 1

What the MRI Actually Shows

Right Kidney Findings

The imaging identified two distinct lesions in the right kidney only:

  • 10 mm T1 hyperintense lesion in the superior pole: T1 bright, T2 dark, no enhancement → classified as Bosniak 2 hemorrhagic/proteinaceous cyst 1
  • 8 mm fat-containing lesion in the lower pole lateral cortex: shows signal loss on opposed-phase imaging → consistent with angiomyolipoma 1

Left Kidney Status

  • Completely normal with no hydronephrosis and no focal lesions of any size 1

Management of the Identified Right Kidney Lesions

For the 10 mm Bosniak 2 Hemorrhagic Cyst

No follow-up imaging is required. 1, 2

  • Bosniak 2 cysts (including hemorrhagic/proteinaceous cysts ≤30 mm) are classified as benign findings highly likely (ONCO-RADS category 2) 1
  • The American College of Radiology guidelines state that Bosniak I and II cysts require no further follow-up 2

For the 8 mm Angiomyolipoma

No follow-up imaging is required. 1

  • Angiomyolipomas are classified as benign findings highly likely (ONCO-RADS category 2) 1
  • The presence of macroscopic fat (demonstrated by signal loss on opposed-phase imaging) indicates a benign angiomyolipoma with virtual certainty 1
  • Small angiomyolipomas <1 cm pose minimal risk and do not require surveillance 1

Clinical Pitfall to Avoid

Do not confuse the 10 mm measurement (1.0 cm) with 2.4 cm. The report describes millimeter-sized lesions, not centimeter-sized masses. There is no 2.4 cm lesion anywhere in either kidney on this MRI. 1

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Management of Small Renal Lesions Identified on Imaging

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.