How stringent or flexible are you with concurrent chemotherapy and radiation starting on the same day in the definitive CRT setting for HN patients?

I am OK with RT starting a day or two after chemo, usually we may need some extra time planning and doing the vsim, shouldn't really be a big deal with RT starting a little after since the chemo is a sensitizer and it will already be in the patients system when we start RT

Although we make every attempt to start C1 with the first day of RT and this is achievable in the vast majority of patients, I don’t mind C1 delivered within a day or 2 after starting RT. We avoid starting C1 before RT.

I was burned once after starting RT the morning before chemo and then the patient's labs were subpar and the medical oncologist decided not to start chemo for a week. I now request that the patient has chemo infusing prior to starting RT - or at a minimum has labs and is cleared to start by med onc ...

There is no data to guide the answer to this question. We do not start chemotherapy before radiation. If the patient cannot tolerate radiation the first day (claustrophobia, medical event, etc), we cancel the chemotherapy as well. Sometimes we start RT on a W/Th/F and the chemotherapy will start the...