1. Brain imaging prior to lung cancer resection
Dr A Addeo
Bristol Cancer Institute
Bristol 23/05/17

2. Background
Consider MRI or CT of the head in patients selected for treatment with curative intent, especially in stage III disease. [new 2011]
Offer patients with features suggestive of intracranial pathology, CT of the head followed by MRI if normal, or MRI as an initial test. [new 2011]
NICE 2011; Lung Cancer: Diagnosis and Management CG121
Hudson et al; 2015; Clinical radiology;

3. Methods List of patients generated from pathology database
Search of ICE, including OpenNet for brain imaging
When patient out of area additional local searches undertaken in Bath, Cheltenham and Gloucester for brain imaging
Documentation of whether brain metastases present
Documentation of date of radiological diagnosis with brain metastases and size.
Data subset created of patients with brain metastases identified and further analysis undertaken (see figure)
Data analysis using Microsoft Excel
Poster presentation at BTOG, awating publication on ecancer journal online

4. Results (1)
585 patients underwent lung resection between Jan 2012 and December 2014
471 with accessible radiology records
24 (5%) patients had radiological evidence of brain metastases
5 diagnosed concurrently with primary tumour and treated radically
1 patient dual malignancies with brain metastases from bowel cancer

5. Results (2)
18 patients with radiological evidence of brain metastases that presented after their primary lung surgery
Appearance of brain metastases by days post resection
Date of metastases not available in one patient
Mean
371 days
Range
days
Median
295 days

6. Results (3) 4/18 (23%) presented within 6-12 months of resection
2 no evidence of systemic relapse
1 received SRS and is alive
1 no information available
2 local and nodal relapse
Both died after palliative chemotherapy
5/18 (28%) presented within 6 months of resection
1 received SRS but died of pneumonia 1/12 later
1 no outcome available
3 no information available
2 died
1 alive

7. To determine if the brain metastasis might have been detectable on a preoperative MRI brain we estimated how large a metastasis would have been at the time of surgery.
We calculated the change in diameter of lesions over time using this volume doubling time (rounded to 60 days)
We plotted the change in diameter over time of 2 mm and 5 mm diameter lesions and then plotted the maximum tumour diameter measured on the diagnostic scan against the number of days after surgery that the imaging was performed and the data of surgery was time 0.
Yoo, B.-H. Nam, H.-S. Yang, S.H. Shin, J.S. Lee, S.H. Lee Growth rates of metastatic brain tumors in non small cell lung cancer Cancer, 113 (5) (2008), pp. 1043–1047

8. Brain mts detectable if MRI preop done

9. Results (4) 18 pts (3.8%) developed brain mts after surgery
15/18 (83%) developed neurological symptoms within 2 years form surgery
Using cut off MRI 5 mm, 12/18 patients (66%) would have been diagnosed at time 0 (surgery)
Using cut off MRI 2 mm, 14/18 patients (78%) would have been diagnosed at time 0 (surgery)

10. Results (5)
Overall patients had 5.0% (24/471) chance of having radiological evidence of brain metastases at some point
3.8% (18/471) chance of developing radiological evidence of brain metastases after surgery
2% (9/471) of patients had radiological evidence of brain metastases within 12 months of their surgery
1% (5/471) of patients had radiological evidence of brain metastases within 6 months of their surgery
Staging at diagnosis: 4 stage IA, 1 IB, 2 stage IIA, 4 stage IIB ad 7 Stage IIIA.

11. Limitations
Only 471 over 585 patients information available. Nearly 20% of the case couldn’t b analysed because imagines were imported only temporary
Impossible make any real assessment on OS or predict if by detecting brain mts preop in our study the OS would have been better. We now that detecting and treating oligometastic disease could improve OS though.
The calculation of the growth curves is a ,although based on the best evidence in the literature, as assumed exponential growth.

12. Conclusion
The incidence of brain mts in our case study is in line with other similar studies. (5%)
The vast majority of them occurs within the first 2 years 15/18 (78%)
Likely that if we had used MRI preop with 2 or 5 mm cut off 14/15 (93%) and 12/15 (80%) would have been detectable at the time of surgery.
No correlation between brain mts and staging in our study.

13. Conclusion bis
Given our finding and previous similar experience brain MRI preop could detect brain mts upfront in the vast majority of the patients
MRI brain should be performed as part of the staging before radical lung surgery.
Cost effect analysis is warranted prior to implementation in routine clinical practice.