Current stage IV adenocarcinoma lung cancer patient diagnosed in June 2012 with mets in spine, lymph nodes and multiple ( 8+) brain mets. EGFR positive with exon 19 deletion. Treated first line with Tarceva 150 mg thru Nov 2012, 75 mg thereafter. Scans since Sept 2012 show lung, spine and lymph node tumors greatly reduced, minimal uptake on Pet scans. Brain mets also show significantly diminished size and activity. Latest scan in May 2013 shows no progression.
Due to severe side effects oncologist has recommended dosage reduction to 25 mg. Does this reduced dosage increase the lilehood for progression of brain mets, even when primary and other mets remain progression free?.
Does taking time off from Tarceva-up to six weeks-increase the likehood of progression of brain mets?
Does taking time off from Tarceva increase the risk of acquiring resistance once treatment is resumed?
Reply # - May 24, 2013, 12:11 PM
Reply To: Stage Iv lung cancer with brain Mets treated with
Hello Mike, Welcome to Grace. I'm very sorry you are in this lousy situation but I'm sure we will be able to help you come to a clearer understanding of your choices. Not that anything with this disease is clear cut.
Unfortunately there is no data that can answer you questions. At this time there are only judgement calls from the ones closest to the case.
What is known is that people do better, live longer and with better quality of life, when treatment doesn't cause significant side effects.
Your last concern about quicker acquired resistance (AR) from a treatment break is hopefully wrong. Actually some oncologists are hoping for the opposite and often allow treatment breaks in order to prolong tarceva's efficacy.
There just isn't enough known about tarceva and brain mets to say for sure but your thinking is right. Less may effect how well tarceva may work on those mets.
However if the side effects are so significant your oncologist wants you on less that is certainly reason to consider other options.
WBR, whole brain radiation is the other option. There is much written on the subject here and I suggest you do some reading perhaps start here on our "General Cancer Info" tab. Select "radiation oncology" use the drop down menu on the right and select "brain radiation" or click the link I pasted.
http://cancergrace.org/radiation/category/brain-radiation/
With a lower dose you will have a chance to feel quite well while keeping the cancer at bay for some time to come and if the brain mets begin to grow WBR can be used to take care of them.
I hope this is a good start to an answer. Let us know,
Janine
forum moderator
Reply # - May 24, 2013, 09:08 PM
Reply To: Stage Iv lung cancer with brain Mets treated with
It's great to hear about how well controlled your cancer has been on treatment thus far.
Janine's exactly right. There's no evidence to say that people responding well on an EGFR tyrosine kinase inhibitor but requiring dose reductions do any worse than other people. Because Tarceva (erlotinib) even at full dose doesn't get into the central nervous system to any significant degree, I would infer that there is no significant decrease in efficacy with a dose reduction. And there's no evidence to suggest that dose reductions for side effects lead to earlier development of acquired resistance.
None of these questions has been addressed in actual clinical trials, however.
Good luck.
-Dr. West
Reply # - May 26, 2013, 04:45 AM
Reply To: Stage Iv lung cancer with brain Mets treated with
Thank you Dr West and Janine for your quick responses. Your link to brain radiation was quite informative although I hope and pray that my brain mets remain under control.
It seems that at this point in my treatment it is a struggle between risk and reward-a better quality of life vs progression of the cancer.
I understand that the median progression free period for those patients being treated first line with Tarceva with EGFR positive 19 exon deletion is approx 9-11 months, which I have now passed. Are there any statistics as to how long Tarceva continues to work for those patients who have exceeded that milestone? I have seen anedotal reports of 4 + yrs but what is the most likely time frame ?
Regarding stopping the Tarceva for a period ot time in order to allow my body to heal from the side effects- is there any optimal period? Although my oncologist has suggested stopping for up to six weeks he acknowledged that there is a likehood that the cancer will begin to progress in approx 1 month, although any progression should start very gradually.However, I have read that a sizable minority of patients (approx 25% ??) exhibit what is called a "flare up", or rapid progression,of the cancer. Is this correct ? And does a "flare up" reduce the likehood that the Tarceva will continue to work at the lower dosage once treatment is resumed.
Thank you again for your responses and kind thoughts.
Reply # - May 26, 2013, 11:10 AM
Reply To: Stage Iv lung cancer with brain Mets treated with
six weeks seems like a long time to be off tarceva to heal from its side effects. There are many people who stop for days though and feel better. You're right about the possible flair up though I'm not sure about the percentages, that would be a guess because I don't of any studies that would determine it.
As for how long you could benefit from tarceva there are many people who have been on the drug for well over a year and into 4 and 5 years. The 9-11 month is a median figure that is just a number found by calculating all the hundreds of numbers in a study. While easier said than done it's best to forget that number and focus on your success.
Your questions are quite normal and much has been written on the subjects. Our forums are a great place to kick around to find lots of good quality info. Here's a link to our EGFR tki forum. http://cancergrace.org/forum/cancer-treatments-symptom-management/egfr-…
Reply # - May 26, 2013, 06:49 PM
Reply To: Stage Iv lung cancer with brain Mets treated with
There's no way to estimate how long someone will continue to respond if they've passed 9-11 months. I'd estimate that about 10% respond for more than two years, so it's not rare but relatively uncommon to see someone respond for several years.
We do typically expect to see progression within a couple of months of stopping, so most commonly we give people just 1-2 weeks off of an EGFR inhibitor, bringing down the dose as needed to get to a point where people can stay on it for a long period of time. It's also true that the risk of "flare" or rebound progression is somewhere in the range of 20-25%, and that's dramatic progression that can even lead to hospitalization or death within 2 weeks off of the EGFR inhibitor. You can read more about that here:
http://cancergrace.org/lung/2012/06/19/chemo-with-or-without-ongoing-eg…
Good luck.
-Dr. West