Hi,
Has anyone ever used irinotecan as part of the nsclc treatments? I was told it has higher response rate in Asian. Is it true?
Can irinotecan be used along with lung radiation? The tumor is at lease 10cm now with high concerning for invasion of the pericardium. Recently he has asthma like wheezing and heart palpitations. we ask for local radiation on the lung tumor to reduce the size and symptoms. First, the oncologist didn't agree and thought that is not necessary. Finally, I got her to say okay on radiation, but she will hold the chemo at least 4 weeks after lung radiation. She wants to check if radiation works/shrinks the tumor before starting chemo. She said if using both at the same time, we will not know which one is actually working. I want to know if it is typical practice to avoid chemo during radiation. Can radiation be done in-between the irinotecan?
She also wants me to find research papers to show her irinotecan is better than taxol before prescribing irinotecan for my dad. (She prefers taxol. She said that is standard of care treatments). I have a hard time finding those data (most of them require me to pay to access). Can anyone help me on this?
Thanks,
Kkh
Reply # - March 2, 2017, 05:41 AM
Hi Kkh,
Hi Kkh,
Irinotecan is a drug that is used primarily in small cell lung cancer (SCLC), but much less commonly in NSCLC. It has some activity in that setting, but usually would not be a leading choice, especially in a pre-treated patient who has not previously used a taxane such as taxol or docetaxel.
As far as holding chemotherapy around the time of radiation, Dr. West has noted:
"...chemotherapy drugs differ in how much they sensitize cancer cells (and normal tissues) to radiation. Some drugs, like cisplatin and etoposide, can be given at full doses and provide the right amount of radiosensitization. Taxol (paclitaxel) and Taxotere (docetaxel) can be given with radiation, but the doses must be reduced substantially, to a level that would not be considered as effective at fighting micrometastases as full doses. Gemcitabine is an incredibly potent radiosensitizer and is not considered safe in combination with radiation for lung cancer." - http://cancergrace.org/lung/2010/08/22/introduction-to-locally-advanced…
When a chemo drug which is a strong radiosensitizer is used in conjunction with radiation, it increases the effective dose of the radiation. Although that may seem like a good idea to help kill cancer cells effectively, radiation doses are set at amounts that will kill cancer cells without causing too much damage to healthy cells. Effectively increasing the radiation dose by using a radiosensitizing chemo drug will result in more damage to normal cells and increase the side effects of radiation. And administering radiation in between doses of chemotherapy does not provide enough separation in time to avoid those negative effects.
JimC
Forum moderator
Reply # - March 2, 2017, 07:41 AM
Hi JimC,
Hi JimC,
The regimen irinotecan and avastin is actually recommended by Stanford oncologist. She also wants my dad to get radiation to shrink the main lung tumor too (because it is too big that invading the pericardium). All of these are banned by his kaiser oncologist because she prefers go by standard of care treatment (taxol will be the next line of treatment). I just don't like when she said standard of care. That is old school style. Now cancer patients should be treated individually base on patient's condition, concurrent med, ethnicity, and gene mutation.
Irinotecan is a potent radiosensitizing agent.
I don't have access to medical research articles online unless I pay out of pocket to get the permission to read, but these are what I found so far:
1. https://meetinglibrary.asco.org/content/149149-156
2. https://www.researchgate.net/publication/281749146
3. https://www.ncbi.nlm.nih.gov/pubmed/12375796
That is why I come here to ask for help.
Kkh
Reply # - March 2, 2017, 08:24 AM
Hi kkh,
Hi kkh,
Thank you for pointing us to those references. The first refers to the use of irinotecan to treat brain metastases in NSCLC, which has been tried over the years with some success. In that regard it might be an option to try to treat your dad's LMC, where it may have activity. The thinking would be to use an agent which isn't necessarily the best-proven choice for NSCLC but which does have activity in that setting, in order to treat the disease in the lung, while possibly successfully treating the LMC. There isn't clear evidence that it will do so, but it is an option which is quite reasonable under the circumstances.
The other two links, which also provide interesting results, are based on small Phase I and II studies, so although those results appear promising, they have not been proven effective in a larger, randomized Phase III study. That doesn't mean it's not an option, but there are many proposed treatments which appear promising in early trials but do not hold up on further testing. As long as the still-experimental nature of the regimen is clear to the patient, then it certainly represents a reasonable path to take.
Being a potent radiosensitizer, it would likely be necessary to separate its use from that of radiation, to avoid potent side effects.
Good luck with whichever regimen is pursued.
JimC
Forum moderator
Reply # - March 2, 2017, 09:17 AM
JimC,
JimC,
Thanks for prompt response. Is it possible to ask any inputs from Dr. West?
Thanks,
Kkh