What is the recommended timing for repeat imaging after lung cancer resection?

From the Guidelines

After lung cancer resection, patients should undergo surveillance imaging annually after the first 2 years. This recommendation is based on the American Society of Clinical Oncology (ASCO) guideline for lung cancer surveillance after definitive curative-intent therapy 1. The guideline suggests that there is no proven clinical benefit to tailoring the surveillance strategy based on the stage at presentation.

Surveillance Strategy

The surveillance strategy should include:

• Annual surveillance imaging after the first 2 years
• CT surveillance (every 6 months for the first 2 years, then annually) to identify locoregional-only recurrences and second primary lung cancers
• The initial post-operative baseline CT scan should be obtained within 3 months after surgery
• Imaging should include a contrast-enhanced CT scan of the chest and upper abdomen to evaluate both the surgical site and potential areas of metastasis

Rationale

The rationale behind this strategy is that it allows for early detection of recurrence or new primary lung cancers, which are most common within the first two years following resection. Although more frequent imaging may detect asymptomatic recurrences earlier, this does not translate into a survival benefit in the available studies 1. The panel determined that biannual imaging for the first 2 years rather than 3 years was indicated based on the limited body of evidence combined with patient factors, resource availability, and expert opinion.

Key Considerations

Some key considerations include:

• High-risk patients may benefit from more frequent imaging at 3-month intervals, while lower-risk patients might follow the 6-month schedule
• PET-CT scans are not routinely recommended for surveillance unless there are specific concerns about recurrence
• Patients should also receive clinical evaluations with their imaging to assess for symptoms that might indicate recurrence
• The potential benefit of surveillance imaging is modestly stronger than potential harm in this high-risk patient population 1

From the Research

Timing of Repeat Imaging after Lung Cancer Resection

The optimal timing for repeat imaging after lung cancer resection is not explicitly stated in the provided studies. However, the studies suggest the importance of surveillance imaging in detecting recurrence and guiding treatment decisions.

• The study by 2 compared the diagnostic value of positron emission tomography (PET) and PET/computed tomography (CT) with conventional imaging techniques for detecting lung cancer recurrence, but did not specify the optimal timing for repeat imaging.
• The study by 3 found that surveillance PET/CT did not result in improved survival or decreased time to detection of recurrence in stage III non-small-cell lung cancer patients treated with definitive radiation, but the study did not investigate the optimal timing for repeat imaging.
• The study by 4 found that PET/CT results significantly correlated with recurrence in pathologic stage I lung cancers, and that patients with high maximum standardized uptake values (SUVs) and lymphovascular invasion were more likely to have recurrence, but the study did not specify the optimal timing for repeat imaging.
• The study by 5 found that PET scanning was effective in detecting and following the progression of recurrent lung cancer, and that retreatment of patients with asymptomatic recurrent tumor based on PET evidence resulted in absent or decreased FDG activity, but the study did not investigate the optimal timing for repeat imaging.
• The study by 6 discussed the role of postoperative radiation therapy (PORT) in patients with locally advanced resected non-small-cell lung cancer, but did not provide guidance on the optimal timing for repeat imaging after lung cancer resection.

Factors Influencing the Timing of Repeat Imaging

Several factors may influence the timing of repeat imaging after lung cancer resection, including:

• The stage and type of lung cancer
• The presence of lymphovascular invasion or other high-risk features
• The patient's overall health and performance status
• The results of previous imaging studies
• The availability of effective treatment options for recurrence

However, the provided studies do not provide clear guidance on the optimal timing for repeat imaging after lung cancer resection. Further research is needed to determine the best approach to surveillance imaging in this patient population.