Target volume for postoperative vaginal cuff brachytherapy in endometrial cancer

[Palex80]

Hello!

What is your target volume for for postoperative vaginal cuff brachytherapy in endometrial cancer (adjuvant, R0).
Do you treat the proximal half of 2/3 of the vagina? Do you use a firm cm-PTV (3?, 4?, 5? cm)?

ABS recommends half of the upper vagina and avoiding dose to the introitus, which seems logical. Does anyone know of any recurrence analysis? A colleague told me that in a recent ESTRO workshop it was suggested to treat only the upper 1/3 of the vagina, but I am a bit concerned...

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[deleted4401]

On CT, I contour out the upper 3cm of the vaginal cylinder. Then, I add a 0.5cm margin. Then, carve out any bowel that might overlap with the volume (typically, only superiorly). That's the CTV. CTV=PTV for brachytherapy, with the assumption that there is no setup error/motion, since it's fixated up there. 7Gy x 3 to 0.5cm if primary adjuvant therapy, 5 Gy x 2 to 0.5cm if after EBRT. Even though there is a volume, that's just for my eyes, the physicist seems to be just prescribing to the 0.5cm. That's what they did at UPMC with good results, and they do 100s a year.

 

[ShirleyT]

good question. actually i have not been doing CT-based planning for these patients, but i do place seeds in the vaginal apex to make sure the applicator is in correct position on plain films, then i prescribe 6 Gy x 5 to the vaginal surface for HDR alone.

 

[medgator]

Proximal 4-6 cm

I think some recommend treating a longer length for bad histologies (papillary serous etc)

 

[Palex80]

I have been treating the proximal two thirds of the vagina so far, measurung the vaginal length from the surgical scar to the introitus.

 

[Reaganite]

I have been treating the proximal two thirds of the vagina so far, measurung the vaginal length from the surgical scar to the introitus.

There does not seem to be any standard. It seems like a lot of places treat the upper half, but I know some facilities will treat any length vagina with ovoids alone. I've worked with one of the bigger names in gyn rad onc (a current oral board examiner) and she treated the upper half in most cases. I recently heard a lecture by Dr. Viswanathan from MGH and she stated that she will include the whole vagina (actually 1 cm short of introitus) for pap serous, clear cell, or when patient has LVSI. I had never heard LVSI as an indication to treat the whole vagina, but she said that in her own practice she has seen enough distal vaginal failures in patients with LVSI that she routinely includes most of the vagina in these cases.

 

[deleted4401]

Hmm... Never heard this about lvsi or high grade tumors.
Is there data? Good to know, though...

 

[medgator]

There does not seem to be any standard. It seems like a lot of places treat the upper half, but I know some facilities will treat any length vagina with ovoids alone. I've worked with one of the bigger names in gyn rad onc (a current oral board examiner) and she treated the upper half in most cases. I recently heard a lecture by Dr. Viswanathan from MGH and she stated that she will include the whole vagina (actually 1 cm short of introitus) for pap serous, clear cell, or when patient has LVSI. I had never heard LVSI as an indication to treat the whole vagina, but she said that in her own practice she has seen enough distal vaginal failures in patients with LVSI that she routinely includes most of the vagina in these cases.

I've seen a couple in practice (not my patients) where they had high-grade histology. A real bummer when they get a distal vaginal recurrence outside of your field/brachy Tx

 

[FractionJackson]

Any recs for the length/proportion of vagina to treat for post-op carcinosarcomas (HG)?
Dose/fractionation? What week into EBRT course do you begin interdigitating?

 

[Palex80]

Any recs for the length/proportion of vagina to treat for post-op carcinosarcomas (HG)?
Dose/fractionation? What week into EBRT course do you begin interdigitating?

We don't give brachytherapy as a boost after EBRT for adjuvant carcinosarcoma treatment, we stick to EBRT only. I am not aware of any trials showing, you should do brachytherapy for carcinosarcomas, so we usually give 50.4/1.8 to the pelvis only (+ boost if R1).

 

[medgator]

Any recs for the length/proportion of vagina to treat for post-op carcinosarcomas (HG)?
Dose/fractionation? What week into EBRT course do you begin interdigitating?

We don't give brachytherapy as a boost after EBRT for adjuvant carcinosarcoma treatment, we stick to EBRT only. I am not aware of any trials showing, you should do brachytherapy for carcinosarcomas, so we usually give 50.4/1.8 to the pelvis only (+ boost if R1).

I agree with Palex

 

[TarHeelRadOnc]

Agree. No adjuvant brachytherapy for carcinosarcoma unless cervix involvement or positive margin.

 

[FractionJackson]

much appreciated guys.

 

[deleted4401]

Is the recurrence pattern different for uterine carcinosarcoma? I've given combination just because they do so poorly and I figure I'll throw the kitchen sink at them.