Magnetic resonance-guided interstitial therapy for vaginal recurrence of endometrial cancer.
OBJECTIVE
To evaluate the feasibility and to describe the acute toxicity of a real-time intraoperative magnetic resonance (MR)-image guided interstitial approach to treating vaginal recurrence of endometrial cancer.


METHODS
From February 2004 to April 2005, 10 patients with recurrent endometrial cancer underwent MR-guided interstitial brachytherapy. Parameters evaluated included needle placement, dose-volume histograms (DVH), and complications.


RESULTS
Magnetic resonance-image guidance resulted in accurate needle placement. Tumor DVH values included median volume, 47 cc; V100, 89%; V150, 61%; V200, 38%; D90, 71 Gy; and D100, 60 Gy. DVH of organs at risk resulted in a median D2cc of external beam and brachytherapy dose (% of brachytherapy prescription): bladder, 75Gy(3) (88%); rectum, 70Gy(3) (87%); and sigmoid, 56Gy(3) (41%). All patients experienced either a Grade 1 or 2 acute toxicity related to the radiation; only 1 patient had Grade 3 toxicity. No toxicities were attributable to the use of MR guidance.


CONCLUSIONS
Real-time MR guidance during the insertion of interstitial needles reduces the likelihood of an inadvertent insertion of the needles into the bladder and the rectum. Three-dimensional dosimetry allows estimation of the dose to organs at risk. Toxicities are limited.
Viswanathan
Akila N
AN
Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA. aviswanathan@partners.org
Cormack
Robert
R
Holloway
Caroline L
CL
Tanaka
Cynthia
C
O'Farrell
Desmond
D
Devlin
Phillip M
PM
Tempany
Clare
C
D000368:Aged; D000369:Aged, 80 and over; D001918:Brachytherapy / Q000009:adverse effects / Q000379:methods*; D012809:Colon, Sigmoid / Q000293:injuries / Q000473:pathology; D016889:Endometrial Neoplasms / Q000532:radiotherapy / Q000601:surgery; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010865:Pilot Projects; D011446:Prospective Studies; D011879:Radiotherapy Dosage; D012007:Rectum / Q000293:injuries / Q000473:pathology; D001743:Urinary Bladder / Q000293:injuries / Q000473:pathology; D014625:Vaginal Neoplasms / Q000532:radiotherapy* / Q000556:secondary*