Prospective clinical trial of positron emission tomography/computed tomography image-guided intensity-modulated radiation therapy for cervical carcinoma with positive para-aortic lymph nodes.
OBJECTIVE
To describe a more aggressive treatment technique allowing dose escalation to positive para-aortic lymph nodes (PALN) in patients with cervical cancer, by means of positron emission tomography (PET)/computed tomography (CT)-guided intensity-modulated radiation therapy (IMRT). Here, we describe methods for simulation and planning of these treatments and provide objectives for target coverage as well as normal tissue sparing to guide treatment plan evaluation.


METHODS
Patients underwent simulation on a PET/CT scanner. Treatment plans were generated to deliver 60.0 Gy to the PET-positive PALN and 50.0 Gy to the PALN and pelvic lymph node beds. Treatment plans were optimized to deliver at least 95% of the prescribed doses to at least 95% of each target volume. Dose-volume histograms were calculated for normal structures.


RESULTS
The plans of 10 patients were reviewed. Target coverage goals were satisfied in all plans. Analysis of dose-volume histograms indicated that treatment plans involved irradiation of approximately 50% of the bowel volume to at least 25.0 Gy, with less than 10% receiving at least 50.0 Gy and less than 1% receiving at least 60.0. With regard to kidney sparing, approximately 50% of the kidney volume received at least 16.0 Gy, less than 5% received at least 50.0 Gy, and less than 1% received at least 60.0 Gy.


CONCLUSIONS
We have provided treatment simulation and planning methods as well as guidelines for the evaluation of target coverage and normal tissue sparing that should facilitate the more aggressive treatment of cervical cancer.
Esthappan
Jacqueline
J
Department of Radiation Oncology, Washington University School of Medicine, St Louis, MO 63110, USA. esthappan@radonc.wustl.edu
Chaudhari
Summer
S
Santanam
Lakshmi
L
Mutic
Sasa
S
Olsen
Jeffrey
J
Macdonald
Dusten M
DM
Low
Daniel A
DA
Singh
Anurag K
AK
Grigsby
Perry W
PW
D000328:Adult; D001011:Aorta / Q000000981:diagnostic imaging; D001027:Aortography; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008207:Lymphatic Metastasis; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D011881:Radiotherapy, Computer-Assisted / Q000379:methods; D020266:Radiotherapy, Conformal; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome; D002583:Uterine Cervical Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy* / Q000556:secondary