Given COVID-19, is there a good hypofractionated regimen for postmastectomy radiation for locally advanced breast cancer?

In light of COVID-19, we offer 2.66 x 16 PMRT with comprehensive RNI. This regimen is under study in ALLIANCE A221505, commonly known as RT-CHARM. Primary endpoint is reconstruction complications at 2 years. We discuss with reconstructed patients (most all will take if offered). Routinely given to unreconstructed patients.

Most important constraints:

Lung V18Gy ≤35%, DMax<115%, MHD< 3Gy, Heart V22.5Gy<10% if left side patient

Also accruing is the FABREC study in immediate reconstruction, using both 16 and 15 fraction regimens

Most PMRT studies allow up to 12 weeks time between last chemo (i.e. adjuvant chemotherapy) or last surgery in the neoadjuvant setting. Instead of starting patients during the height of the pandemic, we offer ER+ patients ...

I break these cases down into 3 groups of locally advanced:

1. Intact breast

2. Mastectomy without reconstruction

3. Mastectomy with reconstruction

For #1 and #2, I am routinely offering hypofractionation to the breast/chest wall and RNI to 40 Gy/15 fractions.

For #3, I agree with @Dr. First Last above and discuss treatment per RT CHARM hypofractionated arm, discussing to patients that we don't have a large amount of randomized data with follow-up.