scholarly journals Utilization of PET-CT in target volume delineation for three-dimensional conformal radiotherapy in patients with non-small cell lung cancer and atelectasis

2013 ◽  
Vol 8 ◽  
Author(s):  
Li-Jie Yin ◽  
Xiao-Bin Yu ◽  
Yan-Gang Ren ◽  
Guang-Hai Gu ◽  
Tian-Gui Ding ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Target Volume Delineation ◽  
Target Delineation ◽  
Volume Delineation ◽  
Pet Ct ◽  
Treatment Plans ◽  
Three Dimensional Conformal Radiotherapy ◽  
Nsclc Patients

Background: To investigate the utilization of PET-CT in target volume delineation for three-dimensional conformal radiotherapy in patients with non-small cell lung cancer (NSCLC) and atelectasis. Methods: Thirty NSCLC patients who underwent radical radiotherapy from August 2010 to March 2012 were included in this study. All patients were pathologically confirmed to have atelectasis by imaging examination. PET-CT scanning was performed in these patients. According to the PET-CT scan results, the gross tumor volume (GTV) and organs at risk (OARs, including the lungs, heart, esophagus and spinal cord) were delineated separately both on CT and PET-CT images. The clinical target volume (CTV) was defined as the GTV plus a margin of 6-8 mm, and the planning target volume (PTV) as the GTV plus a margin of 10-15 mm. An experienced physician was responsible for designing treatment plans PlanCT and PlanPET-CT on CT image sets. 95% of the PTV was encompassed by the 90% isodose curve, and the two treatment plans kept the same beam direction, beam number, gantry angle, and position of the multi-leaf collimator as much as possible. The GTV was compared using a target delineation system, and doses distributions to OARs were compared on the basis of dose-volume histogram (DVH) parameters. Results: The GTVCT and GTVPET-CT had varying degrees of change in all 30 patients, and the changes in the GTVCT and GTVPET-CT exceeded 25% in 12 (40%) patients. The GTVPET-CT decreased in varying degrees compared to the GTVCT in 22 patients. Their median GTVPET-CT and median GTVPET-CT were 111.4 cm3 (range, 37.8 cm3-188.7 cm3) and 155.1 cm3 (range, 76.2 cm3-301.0 cm3), respectively, and the former was 43.7 cm3 (28.2%) less than the latter. The GTVPET-CT increased in varying degrees compared to the GTVCT in 8 patients. Their median GTVPET-CT and median GTVPET-CT were 144.7 cm3 (range, 125.4 cm3-178.7 cm3) and 125.8 cm3 (range, 105.6 cm3-153.5 cm3), respectively, and the former was 18.9 cm3 (15.0%) greater than the latter. Compared to PlanCT parameters, PlanPET-CT parameters showed varying degrees of changes. The changes in lung V20, V30, esophageal V50 and V55 were statistically significant (Ps< 0.05 for all), while the differences in mean lung dose, lung V5, V10, V15, heart V30, mean esophageal dose, esophagus Dmax, and spinal cord Dmax were not significant (Ps> 0.05 for all). Conclusions: PET-CT allows a better distinction between the collapsed lung tissue and tumor tissue, improving the accuracy of radiotherapy target delineation, and reducing radiation damage to the surrounding OARs in NSCLC patients with atelectasis.

FDG-PET/CT Imaging for Staging and Target Volume Delineation in Preoperative Conformal Radiotherapy of Rectal Cancer

2008 ◽  
Vol 70 (5) ◽  
pp. 1423-1426 ◽  
Author(s):  
Maria Chiara Bassi ◽  
Lucia Turri ◽  
Gianmauro Sacchetti ◽  
Gianfranco Loi ◽  
Barbara Cannillo ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Fdg Pet ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Ct Imaging ◽  
Target Volume Delineation ◽  
Volume Delineation ◽  
Pet Ct ◽  
Fdg Pet Ct

scholarly journals Assessment of the dosimetric consequences of prostate movement through rectal distension for patients receiving 3DCRT

2011 ◽  
Vol 10 (3) ◽  
pp. 147-158 ◽  
Author(s):  
D.J. Redding ◽  
C.M. Bragg
Keyword(s):  
Ct Scan ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Dose Delivery ◽  
Rectal Distension ◽  
Median Reduction ◽  
Treatment Plans ◽  
Three Dimensional Conformal Radiotherapy

AbstractPurpose: To investigate the dosimetric consequences of rectal distension at the time of the planning computed tomography (CT) scan and any resultant prostate movement on the planned dose delivery for patients receiving three-dimensional conformal radiotherapy (3DCRT) to the prostate.Methods and materials: 25 prostate cancer patients whose planning CT scan demonstrated a full rectum were rescanned after following a laxative protocol. Rectal dimensions on the two scans and 3DCRT treatment plans produced on each plan were compared. The dosimetric implications of changes in rectal size on the treatment plans and the delivered dose were determined. Statistical significance was evaluated with the Wilcoxon signed ranks test.Results: Significant differences in rectal size were found between the initial CT scan and the rescan. The corresponding median change in prostate position was 4.7 mm. The use of planning scans with a full rectum, that is unrepresentative of the rectum, during treatment causes significant reductions in planning target volume (PTV) minimum dose (median reduction 33.7%) and coverage by the 95% isodose (median reduction 3.7% of the PTV).Conclusion: Rectal distension on the initial planning scan can lead to significant PTV underdosage. Patients presenting with large initial rectal fillings must be rescanned in order to avoid a systematic underdosing of the PTV.

scholarly journals FDG-PET/CT imaging for staging and target volume delineation in conformal radiotherapy of anal carcinoma

2010 ◽  
Vol 5 (1) ◽  
Author(s):  
Marco Krengli ◽  
Maria E Milia ◽  
Lucia Turri ◽  
Eleonora Mones ◽  
Maria C Bassi ◽  
...  
Keyword(s):  
Fdg Pet ◽  
Anal Carcinoma ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Ct Imaging ◽  
Target Volume Delineation ◽  
Volume Delineation ◽  
Pet Ct ◽  
Fdg Pet Ct

scholarly journals FDG-PET/CT in the Radiotherapy Treatment Planning of Locally Advanced Anal Cancer: A Monoinstitutional Experience

2021 ◽  
Vol 11 ◽  
Author(s):  
Clelia Di Carlo ◽  
Maika di Benedetto ◽  
Lisa Vicenzi ◽  
Sara Costantini ◽  
Francesca Cucciarelli ◽  
...  
Keyword(s):  
Lymph Nodes ◽  
Anal Cancer ◽  
Dose Escalation ◽  
Locally Advanced ◽  
Target Volume ◽  
Target Volume Delineation ◽  
18Fdg Pet ◽  
Volume Delineation ◽  
Pet Ct ◽  
The Impact

AimsRadiotherapy with concurrent 5-fluorouracil/mitomycin-C based chemotherapy has been established as definitive standard therapy approach for anal cancer. Intensity Modulated Radiotherapy (IMRT) leads to a precise treatment of the tumor, allowing dose escalation on Gross Tumor Volume (GTV), with a surrounding healthy tissues sparing. Our study assessed the impact of 18-Fluorodeoxyglucose positron emission tomography (18FDG-PET/CT) on the radiotherapy contouring process and its contribution to lymphatic spread detection, resulting to a personalization of Clinical Target Volume (CTV) and dose prescription.MethodsThirty-seven patients, with histologically proven squamous cell carcinoma of the anal canal (SCCAC) were analyzed. All patients were evaluated with history and physical examination, trans-anal endoscopic ultrasound, pelvis magnetic resonance imaging (MRI), computed tomography (CT) scans of the chest, abdomen and pelvis and planning 18FDG-PET/CT. The GTV and CTV were drawn on CT, MRI and 18FDG-PET/CT fused images.ResultsThirty-four (91%) out of 37 patients presented lymph nodes involvement, in one or more areas, detected on 18FDG-PET/CT and/or MRI. The 18FDG-PET/CT showed positive lymph nodes not detected on MRI imaging (PET+, MRI−) in 14/37 patients (38%). In 14 cases, 18FDG-PET/CT allowed to a dose escalation in the involved nodes. The 18FDG-PET/CT fused images led to change the stage in 5/37(14%) cases: four cases from N0 to N1 (inguinal lymph nodes) and in one case from M0 to M1 (common iliac lymph nodes).ConclusionsThe 18FDG-PET/CT has a potentially relevant impact in staging and target volume delineation/definition in patients affected by anal cancer. In our experience, clinical stage variation occurred in 14% of cases. More investigations are needed to define the role of 18FDG-PET/CT in the target volume delineation of anal cancer.

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