Assessment of three-dimensional setup errors in image-guided pelvic radiotherapy for uterine and cervical cancer using kilovoltage cone-beam computed tomography and its effect on planning target volume margins

• Published in: Journal of cancer research and therapeutics 2017-01, Vol.13 (1), p.131-136
• Main Authors: Patni, Nidhi, Burela, Nagarjuna, Pasricha, Rajesh, Goyal, Jaishree, Soni, Tej Prakash, Kumar, T Senthil, Natarajan, T
• Format: Article
• Language: English
• Subjects: Accuracy; Biopsy; Cancer therapies; Care and treatment; CAT scans; Cervical cancer; Cone-Beam Computed Tomography; Dose Fractionation; Endometrial cancer; Female; Humans; Medical imaging; Medication errors; Oncology; Patient Positioning; Patients; Pelvis - diagnostic imaging; Pelvis - pathology; Pelvis - radiation effects; Planning; Population; Radiation therapy; Radiotherapy; Radiotherapy Dosage; Radiotherapy Planning, Computer-Assisted; Radiotherapy, Image-Guided; Radiotherapy, Intensity-Modulated - methods; Research centers; Tomography; Tomography, X-Ray Computed; Uterine cancer; Uterine Cervical Neoplasms - diagnostic imaging; Uterine Cervical Neoplasms - pathology; Uterine Cervical Neoplasms - radiotherapy; Uterine Neoplasms - diagnostic imaging; Uterine Neoplasms - pathology; Uterine Neoplasms - radiotherapy
• ISSN: 0973-1482; 1998-4138
• DOI: 10.4103/0973-1482.199451

To achieve the best possible therapeutic ratio using high-precision techniques (image-guided radiation therapy/volumetric modulated arc therapy [IGRT/VMAT]) of external beam radiation therapy in cases of carcinoma cervix using kilovoltage cone-beam computed tomography (kV-CBCT). One hundred and five patients of gynecological malignancies who were treated with IGRT (IGRT/VMAT) were included in the study. CBCT was done once a week for intensity-modulated radiation therapy and daily in IGRT/VMAT. These images were registered with the planning CT scan images and translational errors were applied and recorded. In all, 2078 CBCT images were studied. The margins of planning target volume were calculated from the variations in the setup. The setup variation was 5.8, 10.3, and 5.6 mm in anteroposterior, superoinferior, and mediolateral direction. This allowed adequate dose delivery to the clinical target volume and the sparing of organ at risks. Daily kV-CBCT is a satisfactory method of accurate patient positioning in treating gynecological cancers with high-precision techniques. This resulted in avoiding geographic miss.