What does a LungRads Category 3 result on a low-dose computed tomography (CT) scan mean?

Understanding Lung-RADS Category 3 Results on Low-Dose CT Scan

A Lung-RADS Category 3 finding on a low-dose CT scan indicates a probably benign nodule with a low likelihood (1-2%) of becoming a clinically active cancer, but requires follow-up imaging in 6 months to ensure stability. 1

What Lung-RADS Category 3 Includes:

• Solid nodules measuring 6mm to <8mm in diameter 1
• Part-solid nodules with the solid component <6mm in diameter 1
• New solid nodules 4mm to <6mm in diameter 1
• New part-solid nodules <6mm in diameter 1
• Pure ground-glass nodules >30mm 1

Risk of Malignancy:

• Lung-RADS Category 3 nodules have approximately 1-2% probability of malignancy according to guidelines 1
• In real-world clinical practice, the actual cancer frequency in Category 3 nodules has been observed to be slightly higher at 3.9% 2
• This is still considered a low risk, but warrants appropriate follow-up 1

Recommended Management:

• Current guidelines recommend a follow-up chest CT scan 6 months after the nodule was identified 1
• For pure ground-glass nodules >30mm, a 6-month CT scan is recommended 1
• For part-solid nodules with solid component <6mm, a 6-month CT scan is recommended 1
• If the follow-up scan shows stability (no growth or concerning changes), then annual screening can resume 1

How to Explain to Patients:

1. Explain what was found:

   • "Your lung scan showed a small spot (nodule) that is most likely not cancer. These types of findings are common during lung screening." 1

2. Provide context about probability:

   • "These Category 3 findings have only about a 1-2% chance of being cancer. In other words, about 98-99% of the time, these findings turn out to be non-cancerous." 1

3. Explain the follow-up plan:

   • "To be safe, we recommend a follow-up scan in 6 months to make sure the nodule isn't growing or changing. Growth could indicate something more concerning that would need further evaluation." 1

4. Reassure but emphasize importance of follow-up:

   • "While we expect this to be benign (non-cancerous), it's important to complete the follow-up scan as recommended. Missing follow-up appointments could delay finding a cancer if one were present." 1

5. Address potential anxiety:

   • "It's normal to feel worried when hearing about a finding on your scan. However, these types of findings are very common in lung screening, and the vast majority turn out to be benign." 1

Important Considerations:

• Adherence to follow-up recommendations is crucial but often challenging in real-world practice 3
• Research shows that patients with Category 3 findings have higher adherence rates (53.8%) to follow-up recommendations compared to those with negative findings (Category 1-2) 3
• Former smokers show better adherence to follow-up recommendations than current smokers (50.0% vs 36.2%) 3
• Structured reporting systems like Lung-RADS help standardize management and reduce unnecessary additional testing 1

Common Pitfalls to Avoid:

• Causing unnecessary anxiety: Avoid alarming language while still emphasizing the importance of follow-up 1
• Minimizing the finding: While most Category 3 nodules are benign, follow-up is still essential 1
• Inconsistent follow-up intervals: Adhering to the recommended 6-month follow-up timing is important for proper assessment 1
• Missing the follow-up: Programs should develop strategies to maximize compliance with follow-up exams through reminders, education, and addressing barriers to returning for follow-up 1

By following these guidelines and communication strategies, healthcare providers can effectively manage Lung-RADS Category 3 findings while minimizing patient anxiety and ensuring appropriate follow-up care.