Purpose: To investigate the potential dosimetric benefits from four-dimensional computed tomography (4DCT) compared with three-dimensional computed tomography (3DCT) in radiotherapy treatment planning for external-beam partial breast irradiation (EB-PBI).
Patients And Methods: 3DCT and 4DCT scan sets were acquired for 20 patients who underwent EB-PBI. The volume of the tumor bed (TB) was determined based on seroma or surgical clips on 3DCT images (defined as TB3D) and the end inhalation (EI) and end exhalation (EE) phases of 4DCT images (defined as TBEI and TBEE, respectively).
This study aimed to evaluate the efficacy, toxicity and tolerability of simultaneous modulated accelerated radiation therapy (SMART)-intensity modulated radiotherapy (IMRT) plus cisplatin and 5-fluorouracil (5-FU) chemotherapy for patients with advanced nasopharyngeal cancer (NPC). Forty-five patients with stage II-IV NPC, determined by the American Joint Committee on Cancer system, were treated with prescribed doses of 72 Gy total to the gross tumor volume, 60 Gy to the clinical target volume and metastatic nodal station, and 54 Gy to the clinically-negative neck region. Before radiotherapy, two cycles of cisplatin (30 mg/m(2)/day on days 1-3) plus 5-FU (400 mg/m(2)/day on days 1-5) were delivered every three weeks for two cycles.
View Article and Find Full Text PDFObjective: To explore the dosimetric variance in forward intensity modulated radiotherapy (IMRT) based on 4D CT and 3D CT after breast conserving surgery.
Methods: Seventeen patients after breast conserving surgery underwent 3D CT simulation scans followed by respiration-synchronized 4D CT simulation scans at free breathing state. The treatment plan constructed using the end inspiration (EI) scan was then copied and applied to the end expiration (EE), and 3D scans and dose distribution were calculated separately.
Dosimetric differences were investigated among single and dual arc RapidArc and fixed-field intensity-modulated radiotherapy (f-IMRT) treatment plans for whole pelvic irradiation of lymph nodes. A total of 12 patients who had undergone radical surgery for cervical cancer and who had demonstrated multiple pelvic lymph node metastases were treated with radiotherapy. For all 12 cases, 7-field IMRT, single-arc RapidArc and dual-arc RapidArc were applied with 6 MV and 15 MV X-ray energies.
View Article and Find Full Text PDFObjective: To measure the intrafraction displacement of the mediastinal metastatic lymph nodes of non-small cell lung cancer (NSCLC) based on four-dimensional computed tomography (4D-CT), and to provide the basis for the internal margin of metastatic mediastinal lymph nodes.
Methods: Twenty-four NSCLC patients with mediastinal metastatic lymph nodes confirmed by contrast enhanced CT (short axis diameter ≥ 1 cm) were included in this study. 4D-CT simulation was carried out during free breathing and 10 image sets were acquired.
We investigated the dosimetric differences among volumetric-modulated arc radiotherapy (RapidArc, RA) plans designed for various target volumes in hepatocellular carcinoma (HCC). Ten HCC patients underwent 3D-CT scanning at free breathing (FB), 3D-CT at end inspiration hold (EIH) assisted by an Active Breathing Coordinator (ABC), and 4D-CT scanning. Gross tumor volumes (GTVs) were manually contoured on CT images.
View Article and Find Full Text PDFObjectives: The purpose of this study was to evaluate the geometric accuracy of thoracic anatomic landmarks as target surrogates of intrapulmonary tumors for manual rigid registration during image-guided radiotherapy (IGRT).
Methods: Kilovolt cone-beam computed tomography (CBCT) images acquired during IGRT for 29 lung cancer patients with 33 tumors, including 16 central and 17 peripheral lesions, were analyzed. We selected the "vertebrae", "carina", and "large bronchi" as the candidate surrogates for central targets, and the "vertebrae", "carina", and "ribs" as the candidate surrogates for peripheral lesions.
Background And Purpose: To compare positional and volumetric differences of planning target volumes (PTVs) based on axial three-dimensional CT (3DCT) and four-dimensional CT (4DCT) for the primary tumor of non-small cell lung cancer (NSCLC).
Materials And Methods: Twenty-eight patients with NSCLC underwent 3DCT and 4DCT scans of the thorax during normal free breathing. PTV(vector) was defined on 3DCT using the individual tumor motion vector measured by 4DCT accounting for tumor motion; PTV(4D) was defined on all phases of 4DCT images.
Background: The lung functional status could be displayed on lung perfusion images. With the images, the radiotherapy plans of lung cancer could be guided to more optimized. This study aimed to assess quantitatively the impact of incorporating functional lung imaging into 3-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiation therapy (IMRT) planning for non-small cell lung cancer (NSCLC).
View Article and Find Full Text PDFObjective: To compare the combined FDG PET/CT with PET alone in the detection of lymph node metastasis (LNM) for esophageal carcinoma patient.
Methods: From November 2003 to August 2005, 35 patients with esophageal carcinoma underwent FDG PET/CT before esophagectomy and lymph node (LN) dissection. The patients who had history of previous anticancer treatment or diabetes mellitus and inflammatory lung diseases as well as being inoperable for medical reasons were excluded.
Zhonghua Zhong Liu Za Zhi
January 2006
Objective: To investigate the impact of PET/CT on the clinical staging, target volume delineation and precise radiotherapy (PAR) planning for patients with non-small cell lung cancer (NSCLC).
Methods: PET/CT scanning was performed in 58 histologically proven NSCLC patients for radical radiotherapy or surgery. The clinical staging of all patients was determined by PET/CT according to 1997 World Health Organization (WHO) staging system.