a 47 yr old Ca breast , post bcs pt is Her 2 neu +ve , post sx she has taken 6 cycles CT(FEC) , it took around 3.5 months .Now she is being planned for RT. but the qs is should we start herceptin along with RT or to wait for RT completion or start herceptin before RT? If we give herceptin first then RT will be delayed further . Is this much gap between SX and RT OK?
To answer part of your question there is no evidence per se to contraindicate concurrent adminstration of trastuzumab with radiation therapy except in patients receiving IMN radiation. I came across the following studies:
1. Belkacémi Y, Gligorov J, Ozsahin M, Marsiglia H, De Lafontan B, Laharie-Mineur H, et al. Concurrent trastuzumab with adjuvant radiotherapy in HER2-positive breast cancer patients: acute toxicity analyses from the French multicentric study. Annals of Oncology [Internet]. 2008 [cited 16:13:21];Available from: http://annonc.oxfordjournals.org/content/early/2008/03/15/annonc.mdn029.abstract
2. Halyard MY, Pisansky TM, Dueck AC, Suman V, Pierce L, Solin L, et al. Radiotherapy and Adjuvant Trastuzumab in Operable Breast Cancer: Tolerability and Adverse Event Data From the NCCTG Phase III Trial N9831. Journal of Clinical Oncology. 2009 Jun 1;27(16):2638 -2644. Available from: http://jco.ascopubs.org/content/27/16/2638.abstract
The two articles have analysed the toxicity in a cohort given trastuzumab concurrently with RT. The first study is particularly pertinent for your patient. While skin and esophageal toxicity were not significantly increased, but the cardiac function is reduced more. So I would exercise caution if doing IMN radiation. Radiation pneumonitis is not significantly increased either. In addition this interesting rat model study also suggests there is little increase in late radiation pneumonitis. It is important to stress here that the first study was having a retrospective design for RT data collection. The 2nd study did not allow use of IMN (2% received it though) and though prospective was not designed to answer the question of increase/decrease toxicity with use of trastuzumab and herceptin.
However there are several pertinent issues that the authors of the 1st article pointed out with respect to concurrent use of Trastuzumab and RT in breast cancer patient with IMN reported by shaffer et al in a letter to the editor. The letter is available here and gives a nice highlight of the pertinent issues with shaffer's study which did show no increase in cardiotoxicity with the use of Trastuzumab concurrent with RT.
Hi Sayan, Could you give us more details like her stage, histology and coexisting comorbidities etc?
Hi Sayan,
Chemo and Radiation sequencing has always been an area of debate. Many institutions go by there own policies and many a times wait-times and patient convenience is also taken into account.
We do NOT give Trastuzumab to our patients concurrent with RT, mainly becoz we do not know much about the toxicity profile of these patients. I dont know if other members of the group have tried it and what is the toxicity profile of there patients ?
thanks santamda. early operable , infil ductal ca.no co morbidity. post BCS,
Hi! In my practice, I do give my radiation with herceptin and I am yet to encounter any increased acute effects.Late effects vs decrease in disease control due to delay-I plump for radiation.No IMN so far.CT based planning for all.