Preoperative chemoradiotherapy for locally advanced rectal adenocarcinoma: A dosimetric comparison of intensity-modulated radiation therapy (IMRT) with three-dimensional conformal radiotherapy (3D-CRT).

2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 615-615
Author(s):  
C. T. Tao ◽  
L. M. Scala ◽  
H. Gee ◽  
D. Lim ◽  
B. Padilla ◽  
...  
Keyword(s):  
Small Bowel ◽  
Organs At Risk ◽  
Locally Advanced ◽  
Rectal Adenocarcinoma ◽  
Conformal Radiotherapy ◽  
Preoperative Chemoradiotherapy ◽  
Dosimetric Comparison ◽  
Pelvic Malignancies ◽  
Femoral Heads ◽  
3D Crt

615 Background: Small bowel and bladder toxicities (bleeding, obstruction, perforation, and stricture) are rare but serious late complications of pelvic radiotherapy (RT) related to dose received by these organs. IMRT has been used effectively in other pelvic malignancies (prostate and gynecologic) to decrease the dose to normal tissues when compared to 3D-CRT. Few studies have examined the use of IMRT in rectal cancer to assess whether a similar dose reduction is feasible. Methods: Eight consecutively treated patients with T2/T3 and N0/N1 rectal adenocarcinoma underwent 5-FU based neoadjuvant chemo-RT using 7-field sliding-window IMRT between 2008 and 2010. Retrospectively, conventional 4-field 3D-CRT plans were generated for dosimetric comparison with IMRT treatment plans. Planning target volumes included the gross tumor, rectum, peri-rectal tissues, pre-sacral space, and common and internal iliac lymphatics. Organs at risk included small bowel (contoured as all small bowel identified on the planning CT plus a 1 cm symmetrical expansion), bladder, and femoral heads. Small bowel, bladder, and femoral head mean doses and volumes receiving 45 Gy (V45) were compared between conventional and IMRT plans, respectively. Paired Student's t-test was used for statistical analysis. Results: Mean prescription dose was 52.9 ± 3.3 Gy. Compared to 3D-CRT, IMRT plans had an 11% lower mean dose delivered to the bladder (38.2 ± 4.5 Gy vs 43.1 ± 1.9 Gy, p = 0.028) and 24% lower mean dose to the small bowel (24.0 ± 2.9 Gy vs 31.7 ± 7.7 Gy, p = 0.014). IMRT plans also had a 55% lower bladder V45 (27 ± 19% vs 61 ± 22%, p = 0.0077) and a 96% lower small bowel V45 (1 ± 0% vs 21± 20%, p = 0.021). The femoral heads received a nonsignificant higher mean dose (19.2 ± 3.9 Gy vs 16.6 ± 3.0 Gy, p = 0.069). Conclusions: Small bowel and bladder volume receiving 45 Gy and mean dose were significantly lower using IMRT compared with 3D-CRT planning. More stringent volumetric planning constraints may be necessary to further reduce the dose to the femoral heads. Further study is warranted to examine the clinical benefit of these dosimetric findings. No significant financial relationships to disclose.

Multimodality treatment of locally advanced penile cancer: A contemporary dosimetric comparison and case presentation.

2012 ◽  
Vol 30 (5_suppl) ◽  
pp. 346-346
Author(s):  
John A. Cox ◽  
Jaipreet S. Suri ◽  
Bagi RP Jana ◽  
Eduardo Orihuela ◽  
Jared D. Sturgeon ◽  
...  
Keyword(s):  
Small Bowel ◽  
Penile Cancer ◽  
Organs At Risk ◽  
Combined Modality Therapy ◽  
Locally Advanced ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiation Therapy ◽  
Multimodality Treatment ◽  
Dosimetric Comparison ◽  
Grade Ii

346 Background: There is a paucity of data on the optimal therapy for locally advanced penile cancer (PC). However, advances in other HPV associated neoplasms utilizing combined modality therapy (CMT) have been encouraging. We describe the management of advanced PC with such an approach. Methods: The patient presented following partial penectomy and inguinal dissection with T2N3 disease and extra-capsular extension (ECE). In a multi-disciplinary setting, it was decided to treat him post-operatively with concurrent chemoradiation. CT data sets were used for dosimetric comparison of critical structures (small bowel, rectum, bladder, scrotum, testes, bone marrow, skin, bowel, and femoral heads) and plans were generated using conventional penile fields (3D), Intensity Modulated Radiation Therapy (IMRT), and Volumetric Modulated Arc Therapy (VMAT), minimizing dose to organs at risk while optimizing treatment dose. Results: The patient was treated with IMRT (45 Gy to penile stump, pelvic and inguinal nodes (INs) with a 9 Gy boost to left INs and 15 Gy boost to right INs, due to ECE) and weekly Cisplatin (20 mg/m2). IMRT gave similar coverage and avoidance of normal structures compared to VMAT but with lower mean scrotal dose ( IMRT 27.0 Gy , VMAT 29.9 Gy, 3D 45.6 Gy). There was no >grade II toxicities, with grade II scrotal edema and moist desquamation of bilateral inguinal folds, not requiring treatment breaks. Acute RT toxicities had near resolution at 1 month. The IMRT and VMAT plans vs. the 3D plan had lower mean doses to the normal structures. 3D planning had unacceptable max doses to femoral head (62 Gy) and scrotum (55 Gy). Small bowel, V15Gy ≤ 150 cc was achieved by all plans. Dose homogeneity was improved for IMRT/VMAT vs. 3D planning (max dose 119%). Conclusions: This is one of the first comparisons of contemporary radiation techniques in the multimodality setting of PC. We demonstrate that utilizing IMRT concurrently with Cisplatin is feasible and well tolerated suggesting it a reasonable strategy to obtain durable local control, without which the prognosis is uniformly dismal. Larger studies are warranted to explore this contemporary CMT approach to locally advanced PC.

Dosimetric comparison of 3-dimensional conformal radiotherapy (3D-CRT) and volumetric-modulated arc therapy (VMAT) in locally advanced cancer cervix

2020 ◽  
pp. 1-8
Author(s):  
Animesh Agrawal ◽  
Rahat Hadi ◽  
Satyajeet Rath ◽  
Avinav Bharati ◽  
Madhup Rastogi ◽  
...  
Keyword(s):  
De Novo ◽  
Abdominal Cavity ◽  
Locally Advanced ◽  
Volumetric Modulated Arc Therapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Conformity Index ◽  
Dosimetric Comparison ◽  
Arc Therapy ◽  
3D Crt

Abstract Introduction: Dosimetric advantages of volumetric-modulated arc therapy (VMAT) over three-dimensional conformal radiotherapy (3D-CRT) are not established in a head-on comparison of a uniform group of locally advanced carcinoma of the cervix (LACC). Therefore, we conducted a dosimetric comparison of these two techniques in LACC patients. Materials and methods: Computed tomography (CT) data of histologically proven de novo LACC, including Stage IIB–IIIB and earlier stages deemed inoperable, were included in this prospective observational dosimetric study. Planning was initially done by 3D-CRT technique (dose of 45–50·4 Gy @ 1·8–2 Gy/# was used in the actual treatment), followed by VMAT planning and appropriate dosimetric comparisons were done in 39 cases. Results: For planning target volume coverage, D95, D98 and D100 (p < 0·0001 for all parameters) and V95 and V100 (p = 0·002 and <0·0001, respectively) were significantly improved with VMAT. The conformity index (CI) was significantly better with VMAT (p = 0·03), while 3D-CRT had a significantly better homogeneity index (HI)(p = 0·003). Dose to the urinary bladder was significantly reduced with VMAT compared to 3D-CRT for V20–V50, except V10. The doses to the rectum and abdominal cavity were significantly reduced with VMAT compared to 3D-CRT plans for all parameters (V10–V50). The number of organs at risks (OARs) for which constraints were met was higher with VMAT plans than with 3D-CRT plans, with at least four out of the five OARs protected in 46·1 versus 5·1% and all constraints achieved in 15·4% versus none. Conclusion: We conclude that in dosimetric terms, VMAT is superior to 3D-CRT for LACC.

scholarly journals Pediatric craniospinal irradiation with a short partial-arc VMAT technique for medulloblastoma tumors in dosimetric comparison

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Gerhard Pollul ◽  
Tilman Bostel ◽  
Sascha Grossmann ◽  
Sati Akbaba ◽  
Heiko Karle ◽  
...  
Keyword(s):  
At Risk ◽  
Low Dose ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Volumetric Modulated Arc Therapy ◽  
Conformal Radiotherapy ◽  
Dosimetric Comparison ◽  
Pediatric Medulloblastoma ◽  
Treatment Plans ◽  
3D Crt

Abstract Background This study aimed to contrast four different irradiation methods for pediatric medulloblastoma tumors in a dosimetric comparison regarding planning target volume (PTV) coverage and sparing of organs at risk (OARs). Methods In sum 24 treatment plans for 6 pediatric patients were realized. Besides the clinical standard of a 3D-conformal radiotherapy (3D-CRT) treatment plan taken as a reference, volumetric modulated arc therapy (VMAT) treatment plans (“VMAT_AVD” vs. “noAVD” vs. “FullArc”) were optimized and calculated for each patient. For the thoracic and abdominal region, the short partial-arc VMAT_AVD technique uses an arc setup with reduced arc-length by 100°, using posterior and lateral beam entries. The noAVD uses a half 180° (posterior to lateral directions) and the FullArc uses a full 360° arc setup arrangement. The prescription dose was set to 35.2 Gy. Results We identified a more conformal dose coverage for PTVs and a better sparing of OARs with used VMAT methods. For VMAT_AVD mean dose reductions in organs at risk can be realized, from 16 to 6.6 Gy, from 27.1 to 8.7 Gy and from 8.0 to 1.9 Gy for the heart, the thyroid and the gonads respectively, compared to the 3D-CRT treatment method. In addition we have found out a superiority of VMAT_AVD compared to the noAVD and FullArc trials with lower exposure to low-dose radiation to the lungs and breasts. Conclusions With the short partial-arc VMAT_AVD technique, dose exposures to radiosensitive OARS like the heart, the thyroid or the gonads can be reduced and therefore, maybe the occurrence of late sequelae is less likely. Furthermore the PTV conformity is increased. The advantages of the VMAT_AVD have to be weighed against the potentially risks induced by an increased low dose exposure compared to the 3D-CRT method.

Helical Tomotherapy Significantly Reduces Dose to Normal Tissues When Compared to 3D-CRT for Locally Advanced Rectal Cancer

2009 ◽  
Vol 8 (5) ◽  
pp. 379-385 ◽  
Author(s):  
Pavan M. Jhaveri ◽  
Bin S. Teh ◽  
Arnold C. Paulino ◽  
Mindy J. Smiedala ◽  
Bridget Fahy ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Small Bowel ◽  
Normal Tissue ◽  
Helical Tomotherapy ◽  
Locally Advanced ◽  
Advanced Rectal Cancer ◽  
Locally Advanced Rectal Cancer ◽  
High Dose ◽  
Femoral Heads ◽  
3D Crt

Combined modality treatment (neoadjuvant chemoradiotherapy followed by surgery) for locally advanced rectal cancer requires special attention to various organs at risk (OAR). As a result, the use of conformal dose delivery methods has become more common in this disease setting. Helical tomotherapy is an image-guided intensity modulated delivery system that delivers dose in a fan-beam manner at 7 degree intervals around the patient and can potentially limit normal tissue from high dose radiation while adequately treating targets. In this study we dosimetrically compare helical tomotherapy to 3D-CRT for stage T3 rectal cancer. The helical tomotherapy plans were optimized in the TomoPlan system to achieve an equivalent uniform dose of 45 Gy for 10 patients with T3N0M0 disease that was at least 5cm from the anal verge. The GTV included the rectal thickening and mass evident on colonoscopy and CT scan as well as with the help of a colorectal surgeon. The CTV included the internal iliac, obturator, and pre-sacral lymphatic chains. The OAR that were outlined included the small bowel, pelvic bone marrow, femoral heads, and bladder. Anatom-e system was used to assist in delineating GTV, CTV and OAR. These 10 plans were then duplicated and optimized into 3-field 3D-CRT plans within the Pinnacle planning system. The V[45], V[40], V[30], V[20], V[10], and mean dose to the OAR were compared between the helical tomotherapy and 3D-CRT plans. Statistically significant differences were achieved in the doses to all OAR, including all volumes and means except for V[10] for the small bowel and the femoral heads. Adequate dosimetric coverage of targets were achieved with both helical tomotherapy and 3D-CRT. Helical tomotherapy reduces the volume of normal tissue receiving high-dose RT when compared to 3D-CRT treatment. Both modalities adequately dose the tumor. Clinical studies addressing the dosimetric benefits are on-going.

Evidence for improved pathologic complete response (PCR) rate after preoperative chemoradiotherapy with 5-FU/oxaliplatin (5FU/OX) for rectal cancer

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 3567-3567 ◽  
Author(s):  
C. M. Dolinsky ◽  
N. N. Mahmoud ◽  
R. Mick ◽  
W. Sun ◽  
R. W. Whittington ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Retrospective Study ◽  
Residual Disease ◽  
Locally Advanced ◽  
Pathologic Complete Response ◽  
Rectal Adenocarcinoma ◽  
Preoperative Chemoradiotherapy ◽  
Malignant Cells ◽  
Long Term Outcomes

3567 Background: The use of preoperative chemoradiotherapy (chemo/RT) with 5-FU for locally advanced rectal cancer has increased dramatically. The addition of oxaliplatin (OX) to preoperative 5-FU may be a more active regimen than 5-FU alone. This retrospective study was undertaken to describe clinical outcomes in patients (pts) with rectal cancer treated with 5FU/OX or 5-FU alone. Methods: Between 11/90 and 4/05, 114 pts with rectal adenocarcinoma underwent preoperative chemo/RT at the University of Pennsylvania. Chemotherapy consisted of 5FU/OX in 36 (32%) pts and 78 (68%) pts received 5-FU. All pts received preoperative RT (median dose 5040 cGy). The two groups were balanced in terms of demographic and tumor related factors including tumor size, stage and distance from the anal verge. Median follow-up from preoperative chemo/RT was 24 months (range 2–125 months). A total of 105 (92%) pts had surgical resections; 61 (58%) with LAR, 44 (42%) with APR. PCR was defined as either no evidence of viable malignant cells in specimen or scattered, isolated malignant cells without gross residual disease. Non-surgical pts were counted as treatment failures. Results: The PCR rate was 36.1% (95% CI 20.4–51.8%) in 5FU/OX pts and 12.8% (95% CI 5.4–20.2%) in 5-FU pts. The probability of observing 13 PCRs in 36 5FU/OX pts if the actual PCR rate was 15% is equal to 0.001. Rates of any grade III/IV toxicity were similar between each regimen (20% 5FU/OX vs. 17% 5FU). Long term outcomes (2yr rate±SE) of local control, freedom from distant failure and progression-free survival in 23 pts who achieved a PCR were: 100%, 94%±6% and 94%±6%, respectively. In 85 pts with gross residual disease, these rates were: 87%±5, 77%±5% and 71%±6%, respectively. Conclusion: In this retrospective study, patients receiving 5FU/OX with radiation had a higher rate of PCR than those receiving 5FU alone. Overall, a PCR may lead to improved long-term outcomes. A prospective randomized trial to test superiority of the 5FU/OX regimen is warranted. [Table: see text]

Clinical outcomes of IMRT versus 3D-CRT in preoperative chemoradiotherapy for locally advanced rectal cancer (LARC) treated in a community setting.

2015 ◽  
Vol 33 (15_suppl) ◽  
pp. e17756-e17756
Author(s):  
Gustavo Ferraris ◽  
Maria Fernanda Diaz Vazquez ◽  
Jorge Palazzo ◽  
Sharon Salenius ◽  
Steven E. Finkelstein ◽  
...  
Keyword(s):  
Rectal Cancer ◽  
Clinical Outcomes ◽  
Locally Advanced ◽  
Community Setting ◽  
Advanced Rectal Cancer ◽  
Preoperative Chemoradiotherapy ◽  
Locally Advanced Rectal Cancer ◽  
3D Crt

scholarly journals Comparison between Intensity-Modulated Radiotherapy and Three-Dimensional Conformal Radiotherapy for Their Effectiveness in Esophageal Cancer Treatment: A Retrospective Single Institution Study

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Xing-hua Bai ◽  
Jun Dang ◽  
Zhi-qin Chen ◽  
Zheng He ◽  
Guang Li
Keyword(s):  
Esophageal Cancer ◽  
Radiation Therapy ◽  
Locally Advanced ◽  
Three Dimensional ◽  
Intensity Modulated Radiotherapy ◽  
Conformal Radiotherapy ◽  
Intensity Modulated ◽  
Three Dimensional Conformal Radiotherapy ◽  
3D Crt

Although a large number of influential studies that have been conducted worldwide on locally advanced esophageal cancer (EC) have employed the treatment modality of three-dimensional conformal radiotherapy (3D-CRT), an advanced as well as highly conformal technology known as intensity-modulated radiotherapy (IMRT) has attracted increasing attention from the radiotherapy research community. This is because of the clear advantages of IMRT, including decrease in radiation dose that reaches critical cardiopulmonary organs. These two treatment modalities need to be investigated with regard to their effect on local control rate and patient survival. In addition, related clinical factors also need to be explored. Data from a total of 431 patients with locally advanced EC, who underwent radiation therapy between January 1, 2010 and December 31, 2013, were included in the present study. Two hundred and ninety-three patients received 3D-CRT, while 138 patients received IMRT. We constructed propensity score matches to make the two groups be comparable (136 patients in 3D-CRT group and 138 patients in IMRT group. Kaplan–Meier analysis was conducted to evaluate the endpoint of overall survival (OS). A Cox proportional hazards model was employed to analyze the relationship between the associated factors and the outcomes via univariate and multivariate approaches. The mean follow-up period was 36.2 months, and the median follow-up period was 23 months. For the IMRT group, the median OS was 31 months, and the 1-, 3-, and 5-year OS rates were 70.3%, 50.0%, and 42.8%, respectively, while for the 3D-CRT group, the median OS was 22 months, and the 1-, 3-, and 5-year OS rates were 63.2%, 41.0%, and 35.4%, respectively (p<0.05). The univariate analysis revealed that quit drinking, chemotherapy, and concurrent chemotherapy were significant risk factors for the prognosis of EC (p<0.05), as well as the radiation therapy technique used (p=0.052). The multivariate analysis indicated that chemotherapy and quit drinking were independent predictive factors for OS. OS is found to be significantly better in the IMRT group, compared with that of the 3D-CRT group. Even though these outcomes need further validation, IMRT should be considered preferentially as a therapeutic option for EC, in combination with chemotherapy and persuading patients to quit drinking.

Randomized phase II trial of preoperative chemoradiotherapy with or without cetuximab in locally advanced rectal adenocarcinoma.

2014 ◽  
Vol 32 (3_suppl) ◽  
pp. 537-537 ◽  
Author(s):  
A. David McCollum ◽  
Darren M. Kocs ◽  
Punit Chadha ◽  
Michael A. Monticelli ◽  
Thomas E. Boyd ◽  
...  
Keyword(s):  
Local Recurrence ◽  
Locally Advanced ◽  
Rectal Adenocarcinoma ◽  
Advanced Rectal Cancer ◽  
Preoperative Chemoradiotherapy ◽  
Locally Advanced Rectal Cancer ◽  
Preoperative Radiation ◽  
Pelvic Radiotherapy ◽  
Recurrence Rates ◽  
Grade 3

537 Background: Treatment for locally advanced rectal cancer (LARC) includes preoperative radiation concurrent with fluoropyrimidine chemotherapy (CRT). Local recurrence is a problem. Cetuximab is active in colorectal cancer and is effective with radiotherapy in other diseases. This study evaluated the pathologic response rate for LARC treated with preoperative chemoradiotherapy w/wo cetuximab. Methods: LARC (T3/4 or LN+, M0) pts were randomized to Arm1/Arm2. Arm 1 received standard pelvic radiotherapy (5040-5400cGy in daily fractions) with continuous infusional 5-FU (225mg/m2/day); Arm 2 received identical chemoradiotherapy + concurrent cetuximab (400mg/m2 initial dose) 1 week before pelvic radiotherapy, followed by 250mg/m2 weekly for the duration of chemoradiotherapy. After study treatment completion, pts were re-evaluated clinically and radiographically for clinical response. After 6-8 weeks, patients underwent surgical resection. The primary end point was pathologic CR (pCR), and secondary endpoints included ORR, RFS, OS, and local recurrence rates. Results: 139 pts were enrolled (Arm 1=69/Arm2=70); Arm1/Arm2 median age 61/55 yrs, and stage II and III 59%, 39%/40%, 60%. In 124 postsurgery pts, pCR occurred in 17 Arm 1 pts (28.3%, 95% CI 17.5-41.4) and 17 Arm 2 pts (26.6%, 95% CI 16.3-39.1); TRG postsurgery was similar between treatment arms (Table). Grade 3 and 4 toxicities were largely nonhematologic: diarrhea 16%/22%, rash 0%/12%, dehydration 5%/8%, mucositis 5%/6%. The 5-yr RFS for Arm1/Arm2 was 61%/65%, 5-yr OS was 66%/83%, local recurrence was 3%/4%. Conclusions: The addition of cetuximab to preoperative CRT for LARC was associated with increased but manageable toxicities. pCR rates were similar between treatment arms, as were survival statistics and local recurrence rates. No association was found between KRAS status and pCR. Clinical trial information: NCT00527111. [Table: see text]

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