- 59-year old female, never smoker
3/4/2013: diagnosed with stage 4 NSCLC Adenocarcinoma EGFR+, 4 brain mets (1.7cm, 1.3cm, 2mm, 2mm), 3.5cm lung nodule
3/19/2013: Cyber Knife (all mets resolved within a few short months)
4/19/2013: Tarceva 150mg
11/21/2013: VATS lobectomy
3/10/2014: Tarceva 100mg
9/5/2014: new 2mm brain met
11/19/2014: now 4mm brain met treated with Cyber Knife. Resolved in a few months.
12/21/2014: Tarceva 75mg
10/9/2015: two 4mm brain mets, per radiation oncologist it is recurrence on the two smallest 2mm brain mets treated with Cyber Knife back in March 2013.
- NED from the neck down since VATS (11/2013). (Live cancer cells were found in 9 out of 30 mediastinal lymph nodes after VATS.)
- No other health issues. Working full time as a high school math teacher.
- CEA monitored three times: 1.5, 1.7, 1.6
- Guardant liquid biopsy (99.52% no mutations/.48% NF1)
Questions:
1. What is the possibility someone can develop necrosis on two very small brain mets 31 months after Cyber a Knife treatment?
2. Would a PET/CT help distinguish between necrosis and progression?
3. If progression is confirmed, being that I cannot have Cyber Knife in the same spots twice, I have been seen for the possibility of future treatment with LITT (Laser Interstitial Thermal Therapy). Is LITT considered experimental treatment? What are the pros and cons of LITT treatment? What are the risks?
4. Can lung cancer spread in the brain from one area to another, or does it only spread in the brain from traveling from another part of the body below the neck?
5. Can very small brain mets be left alone as long as they do not grow, especially if they are too small to treat with LITT?
Your response will be greatly appreciated?
Faith
Reply # - October 26, 2015, 08:37 AM
Hi Faith,
Hi Faith,
Radiation necrosis can develop over time (I've heard 6-24 months quoted) so it's possible in this case. PET/CT would not be much help, especially the PET component, since normal brain activity causes uptake and the entire brain lights up on the scan. Dr. Loiselle has said "Radiation necrosis is diagnosed pathologically – that is by biopsy and microscopic examination, although there are MRI findings suggestive of radiation necrosis." - http://cancergrace.org/radiation/2008/07/30/wbrt-review/ (Comments about radiation necrosis by both Dr. Goldberg and Dr. Loiselle can be found near the bottom of the Responses section).
LITT has not been discussed here, but is currently under study; its efficacy and risks have not been established, although as with any new technology you will find plenty of hype about it online.
The process of metastasis (in this case to and within the brain) is not fully understood. It can spread to the brain from other parts of the body, and once it has, new mets may form at any time. So although visible metastases may be treated with focal radiation, there may remain individual cancer cells already in the brain.
Especially in a situation in which it may be unclear whether these lesions represent cancer or necrosis, if the lesions are asymptomatic close observation with follow-up imaging at relatively short intervals may be suggested by your medical team.
JimC
Forum moderator
Reply # - October 26, 2015, 06:37 PM
Dear JimC:
Dear JimC:
I can't thank you enough for your quick and detailed response.
I particularly appreciate the opportunity to learn that necrosis can develop many months after treatment. However, I would like to ask you the following:
1. Is there a difference when a radiologist describes a problem area in the brain as a focus of enhancement vs a cortical nodule of enhancement?
2. One of the 4mm nodules of enhancement (supposedly, one of the 2mm lesions previously treated with CK in March 2013) is reported as having a small associated focus of vasogenic edema. The other one is not. With this description, is there still a chance we are dealing with radiation necrosis?
3. In your response, you state that Dr. Loiselle, says: "...there are MRI findings suggestive of radiation necrosis." Can you or Dr. Loiselle elaborate a little more on this?
Thank you in advance and take care!
Faith
Reply # - October 27, 2015, 04:59 AM
Hi Faith,
Hi Faith,
In answer to your questions:
1. I don't think there's really a difference between using the words "focus" and "nodule" in this context. And adding the term "cortical" just makes it clear that it is in the brain and not somewhere else in the head (since the MRI images the entire head, not just the brain).
2. Vasogenic edema can occur as a result of either necrosis or recurrence, so that notation in the report does not favor either diagnosis.
3. From what I've read, radiologists can use a factor known as lesion quotient to determine the nature of the enhancement. In one study of 32 lesions, the lesion quotient was greater than 0.6 in recurrent tumor and less than 0.3 in four out of five cases of radiation necrosis. http://pubs.rsna.org/doi/full/10.1148/rg.325125002
JimC
Forum moderator
Reply # - October 27, 2015, 05:37 PM
Wow, Jim, this is great
Wow, Jim, this is great information... very interesting, indeed!
I can't thank you enough.
May the incredible service you and others provide in this forum come back to you all in the form of health, peace, and happiness!
Faith