Side Effects Of Chemotherapy - Cumulative?

My mom was diagnosed with stage IV adenocarcinoma in January of 2008.  She has a very large tumor in her right lung, lesions on both adrenal glands as well as a small lesion in her brain.  She has undergone radiation to her entire brain as well as three cycles of carboplatin and taxol.  She tolerated all of these treatments very well.  Unfortunately, so did her cancer.

As a second line of treatment, her oncologist put her on Alimta.  We were told that the side effects for this particular type of chemotherapy are minimal.  She tolerated the first two cycles very well; however, the last two cycles have been horrible.  She is in a lot of pain and is incredibly weak.  She also has neurological symptoms - she is incredibly forgetful, confused, etc.  She mixes up names of people frequently.  Since she tolerated the first cycles of Alimta so well, my fear is that it is the progression of her cancer causing these symptoms and not the chemotherapy.

Can the side effects of chemotherapy be cumulative?  In other words, are they more likely to occur and/or occur to a greater degree with each subsequent cycle?  I am searching for any reasons that may help to explain why she has gotten progressively and rapidly worse other than the progression of the cancer.  We have a CT scan, MRI, etc. as well as a second opinion at Sloan-Kettering coming up in a couple of weeks.  Any feedback from anyone who has undergone a similar situation would be very much appreciated!  Thank you!

 ~Mandi : )

i to have stage 4 lung cancer . my first 2 teatments of taxol & simvastan were awful, every side effect possible . then they put me on alimta for the most part (5 traetments it's shrinking 2 of the 3 tumors

my side effects have been minamil . mostly fatigue .

i try to eat as much as i can to keep up my stenght & rest , nutrition is imported

alimta comes to me with better results than other treatments .

but i have heard its different with some people .

all i can advise is to battle ,keep as strong as you can, and know that it will get better but it won't come easy. god bless our care givers , mine take s a lot of abuse at times from me , but there are those good days which i relish mor e & more . every body is different it takes time i think.

keep up your fight, it is winnable ........jim (2 yr survivor)