Margins for BCC

[napoleondynamite]

I have a pt with BCC just above her right eyebrow (maybe 1.5cm away).

In residency, we treated facial lesions slowly (60/30) and 2cm margin.

Two questions:

1) Curious what fractionation schedule others would use - there a million ways to do this. I lean toward 60/30 for cosmesis. Anyone for a much shorter regimen?

2) Are 2cm margins really necessary? Is there any slam-dunk data on this?? In her case, she'd lose an eyebrow if I use margins that big.

I don't treat skin much anymore, so welcome any criticisms and advice!

---

Members don't see this ad.

 

[Cancerdancer]

NCCN guidelines are reasonable and give you some defense.
For BCC < 2 cm they suggest margins of 1-1.5 cm; 64/32, 55/20, 50/15, or even 35/5.
I've done them all; in general I think the 15 fraction schedule is a nice middle ground, but have no problem using 5 fraction for the nursing home patient.

 

[medgator]

I generally do 55/20 unless the patient has wound healing issues or cosmesis concerns in which case it's 64/32.

60/30 is a post op dose per nccn

 

[Palex80]

There are some data allowing you to model margin based on the exact BCC histology. If this is an infiltrative tumor, safety margins should be that big. If however it's not infiltrative, you could possibly keep tighter margins.
Surgical series show low recurrence rates of <5% in tumors smaller than 2cm of diameter resected with a margin of 5mm.

I've always wondered if we should treat lesions like this with one volume only or if we should cone down at some point. When using wide margins of 2 cm we are treating microscopic disease with the same dose as we treat macroscopic disease, which is not smart probably. Perhaps something like 36/3 with a wider margin followed by 18/3 "boost" to the macrscopic tumor with a small "PTV-margin" would be a better way to do this.

 

[seper]

does 2 cm refer to block margin for electron field?

 

[napoleondynamite]

does 2 cm refer to block margin for electron field?

Yes, to block edge

 

[napoleondynamite]

NCCN guidelines are reasonable and give you some defense.
For BCC < 2 cm they suggest margins of 1-1.5 cm; 64/32, 55/20, 50/15, or even 35/5.
I've done them all; in general I think the 15 fraction schedule is a nice middle ground, but have no problem using 5 fraction for the nursing home patient.

Ashamed to admit I didn't check the NCCN guidelines..had no idea they have such a detailed radiation section for skin. Thanks - should have been obvious - but helpful!

 

[napoleondynamite]

I generally do 55/20 unless the patient has wound healing issues or cosmesis concerns in which case it's 64/32.

60/30 is a post op dose per nccn

Interesting. We always did 60/30. I've never done 64/32, but admittedly, I haven't treated a ton of skin in my career. You probably plan these every day though! lol

 

[medgator]

Interesting. We always did 60/30. I've never done 64/32, but admittedly, I haven't treated a ton of skin in my career. You probably plan these every day though! lol

I'll go 15 fractions (or less in the right pt as cancerdancer alluded to above) if it's away from the face, but in the face, I stick to 20 or 32, preferably 20.