q's on XRT for skin cancer

[MOHS_01]

Friends,

I was wondering if you could help me out -- this info is not in any of our books. I would like to have a better idea of what to expect so that I can give the patients a better idea of what they can expect. Specifically, what can they expect as a total number of trips, would they lose their teeth, likelihood of xerostomia, should they expect necrosis with resulting wound care, etc.

A few different scenarios:

1. aggressive basal/squamous cell +/- perineural involvement, head & neck, believed to have negative margins.

2. same as above with positive (or questionable margins)

3. primary treatment of a tumor on the head and neck

Thanks in advance.

---

Members don't see this ad.

 

[xraydude]

I use RT routinely both in definitive treatment of head and neck skin cancers (both basal, squams), and adjuvantly for basal, squam and melanoma with high risk features (ie positive margins, nodes, PNI, etc).

Number of trips depends on lots of factors....I have treated definitively with basals and squams in as few as 4 treatments (32Gy/4fx) to as much as 60-66Gy/30-33 fractions. This depends on size of lesion, location, patient age, etc.

Typically RT for skin lesions is done with electrons which are superficially penetrating, so limited problem with the oral cavity. Certainly around the ear, if there are positive nodes, you may need to mix in photons to get more depth, and you can get some ipsilateral xerostomia, but you just spare the other size. I usually use intra-oral shielding to minimize dose to gums, teeth, so there should be no loss of those.

Typically the skin with erode during RT, but this will granulate in over the next few weeks to completely heal over. I don't ever see necrosis.

In your scenarios, I have used RT in the first often, particularly if the surgeon is concerned about the quality of the margin. PNI trumps it up for me, and in a poorly diff tumor that was invading deeply, I will often consider post op RT, though not always - it's a case by case basis.

Certainly, I give post op RT in situation #2.

For H&N cancer, I use RT alot w/ chemo - either definitively or post-op - it depends on the site, and situation.

Friends,

I was wondering if you could help me out -- this info is not in any of our books. I would like to have a better idea of what to expect so that I can give the patients a better idea of what they can expect. Specifically, what can they expect as a total number of trips, would they lose their teeth, likelihood of xerostomia, should they expect necrosis with resulting wound care, etc.

A few different scenarios:

1. aggressive basal/squamous cell +/- perineural involvement, head & neck, believed to have negative margins.

2. same as above with positive (or questionable margins)

3. primary treatment of a tumor on the head and neck

Thanks in advance.

 

[MOHS_01]

Thanks for the info. I wish that I could run across a review article / CME on the subject, but I have not been able to locate one yet.

 

[Palex80]

Several skin cancers can be dealt with using high-energy x-ray devices as well, for example with 100kV. You can try doing hypofractionation too, like 48 Gy with 3 Gy/d. Some consider even higher doses/day, although I am a bit sceptical about high doses/day in the head area, for cosmetic reasons.
Hypofractionation can be very helpful in treating older patiens (for example 90 year olds with tumors near the eyes or lips) or palliation for skin metastases (for example melanoma mets).

 

[G'ville Nole]

Several skin cancers can be dealt with using high-energy x-ray devices as well, for example with 100kV. You can try doing hypofractionation too, like 48 Gy with 3 Gy/d. Some consider even higher doses/day, although I am a bit sceptical about high doses/day in the head area, for cosmetic reasons.
Hypofractionation can be very helpful in treating older patiens (for example 90 year olds with tumors near the eyes or lips) or palliation for skin metastases (for example melanoma mets).

We will typically limit large volumes and treatments over cartilage to <3 Gy per day, for the reasons you mentioned and the risk of chondronecrosis w/ hypofx. Absolutely agree w/ hypofx for older patients w/ smaller lesions.