comparing AI'S
 

Hello all,

I have a question about the AI'S. I was on arimidix for two yrs but changed because of terrible joint pain and then Femara and it gave me constant diarrhea and now the onc has switched me to aromasin. While I was leaving the onc's office the nurse suggested I should try to stay on one medication since it would be more helpful in preventing a recurrance. I don't think this is true as long as I'm taking one or the other but I plan to ask my onc next visit. But what I was wondering is how the drugs compare with each other. Any info would be helpful. Thanks...

Re: comparing AI'S
 

Melissa,

They belong to the same class of drugs accoding to the description I found in Wikipedia:

http://en.wikipedia.org/wiki/Aromatase_inhibitors

For detailed drug description, try the National Library of Medicine's website:

Arimidex® see Anastrozole

Femara® see Letrozole

Re: comparing AI'S
 

Dear Melissa

There is currently a trial comparing the three AIs in early bc. There have been some very,very small studies comparing them to women who have metastatic disease. In one of these studies, Femara was slightly better but the study population was so small it wasn't statistically significant. You need a huge population.

That said, the best one is the one that gives you the most tolerable side effects (if any). So if Aromisin is the best, great - but if you feel worse than you did on Femara, then maybe switch back.

Try taking the drug at night right before bed. It might help with some of the side effects which might be worse in the first 7-8 hours you are on it and you would be fast asleep.

Re: comparing AI'S
 

I've been on Femara since January 1, 2010 - Like Becky suggests, I take it at night. So far my side effects haven't been too bad - stiffness, hip pain, fatigue.
It is the first AI my onc. put me on, and I will probably continue.

all the best
caya

Re: comparing AI'S
 

I have been having SE from Femara and my onc suggested I try switching to another AI. She has no problem with which one.
The bigger question might be why your onc's nurse would suggest that switching can cause recurrance when it has no basis in fact. She should not be dispensing misinformation.

Re: comparing AI'S
 

Who knows..maybe switching around will one day be found to be the better option. The only things I've come across comparing them is that one researcher recently told me femara reduced aromatase/estrogen the most. Years ago, I read somethng that suggested steroidal AI (Aromasin) might be better against Her2. But I have not seen anything since. For whatever reason, I do seem to see more info bandied about regarding Femara. That can be helpful since there is more research about synergizing combinations with Femara.

Maybe your Vitamin D level could be part of the side effects issue:

Cancer Nurs. 2009 Mar-Apr;32(2):143-50.
Vitamin D insufficiency and musculoskeletal symptoms in breast cancer survivors on aromatase inhibitor therapy.

Waltman NL, Ott CD, Twiss JJ, Gross GJ, Lindsey AM.
College of Nursing, University of Nebraska Medical Center, Lincoln, NE, USA.
Breast cancer survivors (BCSs) on aromatase inhibitor (AI) therapy often experience musculoskeletal symptoms (joint pain and stiffness, bone and muscle pain, and muscle weakness), and these musculoskeletal symptoms may be related to low serum levels of vitamin D. The primary purpose of this pilot exploratory study was to determine whether serum levels of 25-hydroxyvitamin D (25[OH]D) concentration were below normal (<30 ng/mL) in 29 BCSs on AI therapy and if musculoskeletal symptoms were related to these low vitamin D levels. The mean (SD) serum 25(OH)D level was 25.62 (4.93) ng/mL; 86% (n = 25) had levels below 30 ng/mL. Patients reported muscle pain in the neck and back, and there was a significant inverse correlation between pain intensity and serum 25(OH)D levels (r = -0.422; P < .05 [2 tailed]). This sample of BCSs taking AIs had below normal levels of serum 25(OH)D despite vitamin D supplements. This is one of the few studies to document a significant relationship between vitamin D levels and muscle pain in BCSs on AI therapy. Findings from this pilot study can be used to inform future studies examining musculoskeletal symptoms in BCSs on AI therapy and relationships with low serum levels of vitamin D.

PMID: 19125120 [PubMed - indexed for MEDLINE]


More on Vitamin D and the best tests HERE


Maybe calcium or a bisphosphonate would help:

Clin Breast Cancer. 2009 Feb;9(1):34-8.
Aromatase inhibitor-related musculoskeletal symptoms: is preventing osteoporosis the key to eliminating these symptoms?

Muslimani AA, Spiro TP, Chaudhry AA, Taylor HC, Jaiyesimi I, Daw HA.
Division of Clinical and Molecular Endocrinology, Cleveland Clinic Cancer, Cleveland, OH, USA. alaf73@yahoo.com
BACKGROUND: Aromatase inhibitors (AIs) are an effective treatment for postmenopausal women with hormone receptor-positive breast cancer. However, patients receiving AIs report a higher incidence of musculoskeletal symptoms and bone fractures; the mechanism and risk factors for this correlation are not well studied. The aim of this study was to correlate these musculoskeletal symptoms and bone fractures in patients receiving AIs with bone mineral density (BMD), previous tamoxifen use, and administration of calcium/bisphosphonate (Ca/Bis). PATIENTS AND METHODS: We reviewed charts of 856 patients with hormone receptor-positive nonmetastatic breast cancer seen at our institution between January 1999 and October 2007. A total of 316 patients met the inclusion criteria of treatment with one of the AIs for > or = 3 months and availability of a dualenergy X-ray absorptiometry (DEXA) during this treatment. Arthralgia, generalized bone pain and/or myalgia, bone fracture after beginning AIs, any tamoxifen treatment, and Ca/Bis therapy were recorded. RESULTS: Our study demonstrates a significant association between symptoms and DEXA-BMD results (P < .001). Similarly, the group receiving tamoxifen before AIs had fewer patients with arthralgia or generalized bone pain/myalgia or bone fracture (P < .001). Furthermore, the group receiving AIs plus Ca/Bis had more patients without musculoskeletal symptoms and had fewer fractures. Finally, the group receiving steroidal AIs compared with nonsteroidal AIs had more patients with arthralgia or generalized bone pain and/or myalgia, and bone fractures (P < .001). CONCLUSION: Patients on AIs who develop osteoporosis are at increased risk of musculoskeletal symptoms and bone fracture. Comedication with Ca/Bis reduces the likelihood for osteoporosis and musculoskeletal symptoms. Patients who received tamoxifen before AIs were less likely to develop AI-related musculoskeletal symptoms. We recommend that patients on AIs should be offered Ca/Bis to reduce the incidence of musculoskeletal symptoms and fracture, especially if patients are receiving steroidal AI and/or did not receive tamoxifen before AIs.

PMID: 19299238 [PubMed - indexed for MEDLINE]

Re: comparing AI'S
 

Rich - I am interested in your reserach - thank you for sharing - I have copied this and will dig thru later - but from what I have seen these are all post menapausal drugs. ....

Everything (well tons) of the things I have found on hormone therapy (chemically induced menopause as my oncologist explains it in Italian) however.... most all I've found on pre-menopausal women is that Her2 seems to be resistant to hormone therapy.

Does anyone have any information on this?

Curious - as I still have not done anything about hormone therapy and I'm coming up on my year anniversary of surgery.
thank you -------
Karen

Re: comparing AI'S
 

Yes..it does seem trickier in premeno her2 pos. At first glance, it might be sensible to combine Tamoxifen with Herceptin and Tykerb and EGCG (green tea) ..and metformin.

Re: comparing AI'S
 

Yes, however I have already done the chemo and am nearing (2 months) away from finishing Herceptin. I have to read up on the Metformin (don't know anything about it) but will do that reading and look into it.
You seem to be really savvy on combining treatments - thank you so much for posting here and sharing your findings.

I am doing lots holistically - so I am counting heavily on that to keep me from having the Her2 express again. Thankfully I was stage 1 and I found it early. Thank god the lump hurt - if not I would have been in a lot worse shape - as I would have had a hard time finding it - the mamogram probably wouldn't have caught it - as the dr. of x-rays here said it was in a bad spot and he had to work really hard to get a photo of the little bugger!

Thanks again! Your mom is lucky to have you on her team!!!!
Karen

Re: comparing AI'S
 

Thanks to everyone for the info. I guess we will have to wait for the head-to-head comparisons.

Yes, BonnieR, I agree. I was dumbstruck when the nurse said this to me. It made me feel as if she thinks I'm a whiner. I'm going to think on it, at least for a few days, before I respond to her. This is a weak area for me.

Karen - I'm not too logical but just because our cancer is Her2 does not mean that 100% of the cells are Her2. Some may only be PR or ER +. So maybe these cells didn't benefit from herceptin. Does this make sense? I think of it like a vein diagram, each cell may only have one marker or maybe some cells have all three markers. You can see from my history that my pathology report said 80% of my tumor was her2 so that made me wonder about the other 20%. By taking an AI I'm hoping to target any remaining cells that may be ER or PR +. And hoping herceptin targeted the her2's. At least this is what I tell myself.
Thanks again,

Re: comparing AI'S
 

Melissa,
My experience has been that I really had a lot of aches and pains with Arimidex so after 3 years I switched to Aromasin. Sometimes the bottom of my feet burn but over all I am quite satisfied and my oncologist is considering having me go into the after 5 year trial which I am willing to do as long as someone besides my insurance (Tri-Care For Life) and I pay for it. A 3 month supply costs almost $1200.00. My co-pay is only $27.00 but I am not sure Tri-care should have to pay for it if it is a trial!!
Love & Hugs,
Marlys
P.S. I am due to finish the five years in October.

Re: comparing AI'S
 

Melissa, are you sure the Femara is what is giving you the runs rather then another medication or supplement you might be on?
Femara gives me some joint stiffness at night when i am sleeping. I take it at night.