What treatment volumes and dose do you use for postoperative soft tissue sarcoma of the scalp with negative margins?

While there is institutional variation in practice, our standard has been to extend extremity/trunk paradigms to the head and neck region, including the scalp. For negative margins for a scalp sarcoma, we typically use margins of 3-3.5 cm for CTV for the first course and then 1.5-2 cm CTV for the conedown. (I will note that if it is a cutaneous angiosarcoma we are treating, we often add larger margins.) Unless imaging showed concern of involvement of the underlying skull, I do not include the skull itself in the CTV. Hence, the volume looks like a "pancake" along the scalp. Also, important to note that sometimes we do not have preoperative imaging to know where the preoperative GTV was located. In those cases, I best approximate by using th...