scholarly journals Analysis of the Influence of Peripheral Anatomical Changes for CBCT-Guided Prostate Cancer Radiotherapy

2021 ◽  
Vol 20 ◽  
pp. 153303382110163
Author(s):  
Yingjie Zhang ◽  
Xiangbin Zhang ◽  
Jing Li ◽  
Liang Zeng ◽  
Xuetao Wang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cone Beam Ct ◽  
Target Position ◽  
The Body ◽  
Target Dose ◽  
Body Contour ◽  
Volume Variation ◽  
Rectal Volume ◽  
The Mean ◽  
Rectal Filling

Purpose: To analyze the influence of the bladder and rectum filling and the body contour changes on the prostate target dose. Methods: A total of 190 cone-beam CT (CBCT) image data sets from 16 patients with prostate cancer were used in this study. Dose reconstruction was performed on the virtual CT generated by the deformable planning CT. Then, the effects of the bladder filling, rectal filling, and the patient’s body contour changes of the PCTV1 (the prostate area, B1) and PCTV2 (the seminal vesicle area, B2) on the target dose were analyzed. Correlation analysis was performed for the ratio of bladder and rectal volume variation and the variation of the bladder and rectal dose. Results: The mean Dice coefficients of B1, B2, bladder, and rectum were 0.979, 0.975, 0.888 and 0.827, respectively, and the mean Hausdorff distances were 0.633, 1.505, 2.075, and 1.533, respectively. With the maximum volume variations of 142.04 ml for the bladder and 40.50 ml for the rectum, the changes of V100, V95, D2, and D98 were 1.739 ± 1.762 (%), 0.066 ± 0.169 (%), 0.562 ± 0.442 (%), and 0.496 ± 0.479 (%) in PCTV1 and 1.686 ± 1.051 (%), 0.240 ± 0.215 (%), 1.123 ± 0.925 (%), and 0.924 ± 0.662 (%) in PCTV2, respectively. With a 10% increase in the volume of the bladder and rectum, the V75, V70, and V65 of rectum increased at 0.73 (%), 0.71 (%), and 1.18 (%), and the V75, V70, and V65 of bladder changed at −0.21 (%), −0.32 (%), and −0.39 (%), respectively. Conclusion: Significant correlations were observed between the volume variation and the dose variation of the bladder and rectum. However, when a bladder and rectal filling protocol was adopted, the target dose coverage can be effectively ensured based on CBCT guidance to correct the prostate target position.

Probiotics for Rectal Volume Variation During Radiation Therapy for Prostate Cancer

2013 ◽  
Vol 87 (4) ◽  
pp. 646-650 ◽  
Author(s):  
Yongkan Ki ◽  
Wontaek Kim ◽  
Jiho Nam ◽  
Donghyun Kim ◽  
Juhye Lee ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Radiation Therapy ◽  
Volume Variation ◽  
Rectal Volume

scholarly journals Risk Factors for Prostate Cancer Patients Among Gezira State-Central of Sudan

1970 ◽  
Vol 12 (4) ◽  
Author(s):  
Fatima A Hamad ◽  
And D. O. Abuidris
Keyword(s):  
Prostate Cancer ◽  
Risk Factors ◽  
Family History ◽  
Cancer Patients ◽  
The Body ◽  
Control Group ◽  
Education Levels ◽  
Male Patients ◽  
The Mean ◽  
Disease Family

The aim of this study is to assess the risk factors for prostate cancer among Sudanese patients treated in National Cancer Institute (NCI), Gezira University, Wadmedani, Sudan. The study was performed on 268 prostate cancer patients, age ranging between 45-98 years. Similar number of 268 persons (age and sex matched) was used as control group .The study period was from May-2006 to December-2009. Data was collected from patients using a questionnaire which was filled in order to obtain information regarding: age, residence, tribe, education levels, occupation, marital status, stage of disease, family history and habits .The body mass index (BMI) was determined by anthropometrics measurements ( weight& height). Prostate cancer is the commonest cancer among male patients treated in the NCI. The mean age of patients was 72.2±9.25. Most of patients (73.9%) were over 66-years. Family history is positive in 18(6.7%) of the patients. Rural inhabitants were 79.8% of all cases. The disease is equally distributed among different tribes. The illiteracy among cases is 39.1%. The commonest occupation was farming (60.1%). Majority (90.7%) of the patients were married. Most cases (85.4%) presented with stage ІІІ and ІV. 73% of the patients had one or more of unhealthy habits (smoking, snuff and alcohol). the BMI was high in 6.9% of the patients. Risk factors for prostate cancer in the study area, which may appear to have a high significant effect, were: the age, education level, occupation, unhealthy habits and the BMI. ABSTRAK: Tujuan kajian ini dijalankan ialah untuk menilai faktor-faktor risiko untuk kanser prostat di kalangan pesakit-pesakit yang dirawat di Institut Kanser Kebangsaan (NCI), Universiti Gezira, Wadmedani, Sudan. Kajian dijalankan pada 268 pesakit kanser prostat, berumur di antara 45-98 tahun. Jumlah bilangan pesakit yang sama iaitu seramai 268 orang (sama umur dan jantina) telah digunakan sebagai kumpulan kawalan.Tempoh kajian ialah pada Mei 2006 sehingga Disember 2009. Data diperolehi daripada pesakit-pesakit dengan menggunakan boring soal selidik yang diisi untuk mendapatkan maklumat: umur, tempat tinggal, puak, taraf pendidikan, pekerjaan, status perkahwinan, peringkat penyakit, sejarah keluarga dan tabiat-tabiat. Indeks jisim badan (BMI) telah ditentukan melalui pengukuran antropometri (berat dan ketinggian). Kanser prostat ialah kanser yang paling banyak dihidapi pesakit-pesakit yang dirawat di NCI. Purata umur ialah 72.2±9.25. Kebanyakan pesakit (73.9%) berumurlebih 66 tahun. Sejarah keluarga ialah positif pada 18 (6.7%) pesakit. Penduduk luar bandar ialah 79.8% daripada keseluruhan jumlah kes. Penyakit ini terbahagi sama rata di antara puak-puak. Kadar buta huruf di antara kes-kes ialah 39.1%. Pekerjaan yang paling banyak ialah bertani (60.1%). Majoriti (90.7%) pesakit telah berkahwin. Kebanyakan kes-kes (85.4%) menghidapi peringkat III dan IV penyakit. 73% daripada jumlah pesakit mempunyai satu atau lebih tabiat yang kurang sihat (merokok, menghidu, dan alkohol). 6.9% pesakit mempunyai indeks jisim badan (BMI) yang tinggi. Faktor-faktor risiko untuk kanser prostat di dalam kawasan kajian yang menunjukkan kesan signifikan yang tinggi ialah: umur, taraf pendidikan, pekerjaan, tabiat-tabiat kurang sihat dan indeks jisim badan (BMI).

scholarly journals Are simple verbal instructions sufficient to ensure that bladder volume does not deteriorate prostate position reproducibility during spot scanning proton therapy?

BJR|Open ◽  
2021 ◽  
Author(s):  
Kentaro Nishioka ◽  
Kento Gotoh ◽  
Takayuki Hashimoto ◽  
Takashige Abe ◽  
Takahiro Osawa ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Proton Therapy ◽  
Bladder Volume ◽  
Fiducial Markers ◽  
Image Guided ◽  
Verbal Instructions ◽  
Spot Scanning ◽  
Prostate Motion ◽  
Rectal Volume ◽  
The Mean

Objectives: The purpose of this study is to investigate whether verbal instructions are sufficient for bladder volume (BV) control not to deteriorate prostate position reproducibility in image-guided spot scanning proton therapy (SSPT) for localized prostate cancer. Methods: A total of 268 treatment sessions in 12 consecutive prostate cancer patients who were treated with image-guided SSPT with fiducial markers were retrospectively analyzed. In addition to strict rectal volume control procedures, simple verbal instructions to void urine one hour before the treatment were used here. The BV was measured by a Bladder Scan just before the treatment and the prostate motion was measured by intraprostatic fiducial markers and two sets of X-ray fluoroscopy images. The correlation between the BV change and prostate motion was assessed by linear mixed-effects models and systematic and random errors according to the reproducibility of the BV. Results: The mean absolute BV change during treatment was from −98.7 to 86.3 ml (median 7.1 ml). The mean absolute prostate motion of the patients in the left-right direction was −1.46 to 1.85 mm, in the cranial-caudal direction it was −6.10 to 3.65 mm, and in the anteroposterior direction −1.90 to 5.23 mm. There was no significant relationship between the BV change and prostate motion during SSPT. The early and late genitourinary and gastrointestinal toxicity was minimal with a minimum follow-up of 4.57 years. Conclusions: Simple verbal instructions about urination was suggested to be sufficient to control the BV not to impact on the prostate motion and clinical outcomes in image-guided SSPT. Careful attention to BV change is still needed when the seminal vesicle is to be treated. Advances in knowledge: Our data demonstrated that there was no apparent relationship between BV changes and prostate position reproducibility and simple verbal instruction about urination could be sufficient for image-guided SSPT.

Dosimetric variations for high-risk prostate cancer by VMAT plans due to patient’s weight changes

2019 ◽  
Vol 18 (4) ◽  
pp. 336-342
Author(s):  
David Miguel ◽  
Victor de la Llana ◽  
Daniel Martinez ◽  
Angel del Castillo ◽  
Delfín Alonso ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
High Risk ◽  
Region Of Interest ◽  
The Body ◽  
Weight Changes ◽  
Body Contour ◽  
High Risk Prostate Cancer ◽  
Gamma Index ◽  
Risk Prostate Cancer ◽  
The Impact

AbstractPurpose:The aim of this study is to investigate the impact of anatomical changes in prostate cancer patients on the target coverage when using 6 MV beams-VMAT therapy and to propose strategies that allow us to evaluate the dose or correct it by normalization without having to perform a new simulation.Methods and materials:Ten patients of high-risk prostate cancer were chosen for the study. All test plans were delivered using the same isocenter and monitor units as the original plan and compared against the original unedited plan. The expansion and contraction of body contours due to size changes was mimicked by increasing and decreasing the body contour with depths of −2, −1·5, …, 1·5, 2 cm, in the anterior, and both lateral directions of the patient. A total of 90 plans were evaluated, 9 for each patient. Dose-volume histogram statistics were extracted from each plan and normalized to prescription dose.Results:Weight changes resulted in considerable dose modifications to the target and critical structures. Plans were found to be varied with 2·9% ± 0·3% per cm SSD change for VMAT treatment with a correlation index close to one. Therefore, doses variations were linear to the changes of depth. Gamma index evaluation was performed for the 10 renormalized plans. All of them passed criteria of 3%/3 mm in at least 98.2% of points. Eight of them passed criteria in 99% points. Gamma index 4%/4 mm passed 100% points in all patients for the chosen region of interest.Conclusions:The dosimetry estimation presented in this study shows important data for the radiation oncology staff to justify whether a CT rescan is necessary or not when a patient experiences weight changes during treatment. Based on the results of our study, discrepancies between real dose and planned dose were >5% for 1·7 cm of difference in external contour in the anterior and both lateral directions of the patient.

Effect of ProSpare (PS), a rectal obturator, on inter- and intrafraction prostate motion and anorectal doses in prostate radiotherapy (RT).

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. e633-e633
Author(s):  
Julia Murray ◽  
Helen McNair ◽  
Emma Alexander ◽  
Tuathan O'Shea ◽  
Karen Thomas ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Controlled Trial ◽  
Cone Beam Ct ◽  
Prostate Radiotherapy ◽  
Intrafraction Motion ◽  
Prostate Motion ◽  
Gi Toxicity ◽  
Single Use ◽  
Rectal Filling ◽  
To Receive

e633 Background: PS is a single use, self-insertable endorectal device designed as a daily image-guidance tool for prostate cancer RT. Rectal filling is a significant factor in prostate motion. We investigated the effect of PS on inter- and intrafraction prostate motion and its effect on anorectal dosimetry. Methods: 19 patients with localized prostate cancer were randomized to receive prostate RT with PS either in the 1st or 2nd half of treatment. For each patient two planning CT scans were acquired, without and with PS. Contours were delineated by one physician and planned with a forward multi-segment technique to a dose of 74Gy/37F. Dose surface histograms were created (VODCA). In all patients, 3 electromagnetic transponders (EM) were implanted into the prostate and daily online image-guided RT was performed using either cone-beam CT (Elekta) or Calypso–based localization with tracking. Interfraction systematic (Σ) and random (σ) errors were estimated for bone matching without and with PS using EM position as reference. CTV-PTV margins were generated using the Van Herk formula. In-house code was used to analyse intrafraction motion recorded by Calypso of the EM centroid in the RL, SI and AP planes for individual fractions. A 2-way ANOVA test (SPSS v22) was used to determine if PS had an effect on maximal intrafraction prostate displacement. Results: See Table. Conclusions: PS affects the dosimetric pattern to the anal canal and rectum and this may impact GI toxicity. Also, PS stabilizes the prostate, which could enable reduced planning margins. PS will now be assessed in post-prostatectomy RT within a randomized controlled trial, POPS. Clinical trial information: 11814. [Table: see text] [Table: see text] [Table: see text]

Preoperative and Postoperative Management of the Body Contour Patient

1996 ◽  
Vol 16 (4) ◽  
pp. 218-223
Author(s):  
R. Rohrich ◽  
P. B. Fodor ◽  
J. J. Petry ◽  
P. Vash
Keyword(s):  
Postoperative Management ◽  
The Body ◽  
Body Contour

The Y-shaped trabecular bone structure in the odontoid process of the axis: a CT scan study in 54 healthy subjects and biomechanical considerations

2019 ◽  
Vol 30 (5) ◽  
pp. 585-592 ◽  
Author(s):  
Nicola Montemurro ◽  
Paolo Perrini ◽  
Vittoriano Mangini ◽  
Massimo Galli ◽  
Andrea Papini
Keyword(s):  
Ct Scan ◽  
Healthy Subjects ◽  
Bone Structure ◽  
Cone Beam Ct ◽  
Odontoid Process ◽  
Trabecular Structure ◽  
Anatomical Entity ◽  
Significant Difference ◽  
Axial Ct ◽  
The Mean

OBJECTIVEOdontoid process fractures are very common in both young and geriatric patients. The axial trabecular architecture of the dens appears to be crucial for physiological and biomechanical function of the C1–2 joint. The aim of this study is to demonstrate the presence of a Y-shaped trabecular structure of the dens on axial CT and to describe its anatomical and biomechanical implications.METHODSFifty-four C2 odontoid processes in healthy subjects were prospectively examined for the presence of a Y-shaped trabecular structure at the odontocentral synchondrosis level with a dental cone beam CT scan. Length, width, and axial area of the odontoid process were measured in all subjects. In addition, measurements of the one-third right anterior area of the Y-shaped structure were taken.RESULTSThe Y-shaped trabecular structure was found in 79.6% of cases. Length and width of the odontoid process were 13.5 ± 0.6 mm and 11.2 ± 0.9 mm, respectively. The mean area of the odontoid process at the odontocentral synchondrosis was 93.5 ± 4.3 mm2, whereas the mean one-third right anterior area of the odontoid process at the same level was 29.3 ± 2.5 mm2. The mean area of the odontoid process and its length and width were similar in men and women (p > 0.05). No significant difference was found in the mean area of the odontoid process in people older than 65 years (94 ± 4.2 mm2) compared to people younger than 65 years (93.3 ± 4.4 mm2; p > 0.05).CONCLUSIONSThe authors identified a new anatomical entity, named the Y-shaped trabecular structure of the odontoid process, on axial CT scans. This structure appears to be the result of bone transformation induced by the elevated dynamic loading at the C1–2 level. The presence of the Y-shaped structure provides new insights into biomechanical responses of C2 under physiological loading and traumatic conditions.

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