Two radiotherapeutic techniques after modified radical mastectomy for breast cancer: A dosimetric study / 医学研究生学报

Objective The aim of this study was to search for a better individualized clinical radiotherapy scheme for breast cancer patients after modified radical mastectomy by comparing the dosimetric data on the radiotherapeutic techniques of three-dimensional conformal radiation therapy (3D-CRT) and volumetric modulated arc therapy (VMAT). Methods This retrospective study included 77 cases of breast cancer treated by modified radical mastectomy followed by radiotherapy in Hebei General Hospital from November 2015 to February 2019. According to the radiotherapeutic techniques used, we divided the patients into a 3D-CRT (n = 54) and a VMAT group (n = 23), Using the dose-volume histogram, we evaluated the dose parameters of the clinical target volume (CTV) and the organs at risk (OAR). Results Compared with the patients in the 3D-CRT group, those in the VMAT group showed significantly decreased V110% ([12.14 ± 14.03]% vs [7.18 ± 6.36]%, P < 0.05), increased conformity index (0.62 ± 0.11 vs 0.66 ± 0.09, P < 0.05), reduced ipsilateral lung dose ([1308.42 ± 276.49] vs [1114.34 ± 233.71] cGy, P < 0.05), V5 (P < 0.05) and V10 (P < 0.05), and elevated contralateral breast dose (P < 0.05) and V5 in those with left breast cancer ([63.49 ± 17.49]% vs [76.97 ± 11.81]%, P = 0.028). Conclusion VMAT can effectively reduce the average dose and the dose in the low-dose area of the ipsilateral lung of the breast cancer patient after modified radical mastectomy. VMAT and 3D-CRT each have its own advantages for specific patients.

Benefit of volumetric-modulated arc therapy over three-dimensional conformal radiotherapy for stage I-II extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in the stomach: a dosimetric comparison

PURPOSE: To retrospectively analyze dosimetric parameters of volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiotherapy (3D-CRT) delivered to extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma) to find out advantages of VMAT and conditions for definite benefits of VMAT. MATERIALS AND METHODS: Fifty patients with stage I-II gastric MALT lymphoma received VMAT (n = 14) or 3D-CRT (n = 36) between December 2005 and April 2018. Twenty-seven patients were categorized according to whether the planning target volume (PTV) overlaps kidney(s). Dosimetric parameters were analyzed by dose-volume histogram. RESULTS: Radiation dose to the liver was definitely lower with VMAT in terms of mean dose (p = 0.026) and V15 (p = 0.008). The V15 of the left kidney was lower with VMAT (p = 0.065). For those with PTV overlapping kidney(s), the left kidney V15 was significantly lower with VMAT. Furthermore, the closer the distance between the PTV and kidneys, the less the left kidney V15 with VMAT (p = 0.037). Delineation of kidney(s) by integrating all respiratory phases had no additional benefit. CONCLUSIONS: VMAT significantly increased monitor units, reduced treatment time and radiation dose to the liver and kidneys. The benefit of VMAT was definite in reducing the left kidney V15, especially in geometrically challenging conditions of overlap or close separation between PTV and kidney(s).

Observation on effect of 3D-CRT combined with DC-CIK cell in treatment of recurrent smell cell carcinoma in high altitude regions / 重庆医学

Objective To investigate the effect of 3‐dimensonal conformal radiotherapy (3D‐CRT ) combined with dendritic cell‐cytokine induced kill (DC‐CIK) cell in the treatment of recurrent small cell lung carcinoma (SCLC) in high altitude regions ,and its influence on VEGF and NSE .Methods Eighty‐five patients with recurrent SCLC in the tumor radiotherapy department of the Qinghai Provincial Fifth People′s Hospital from May 2012 to April 2014 were selected and divided into the control group(41 cases) and observation group(44 cases) according to the random number table .The two groups were respectively treated by 3D‐CRT treat‐ment and 3D‐CRT combined with DC‐CIK treatment cell .The curative effect ,incidence rate of adverse reactions ,levels of VEGF and NSE ,changes of liver and renal function indexes in the two groups were compared before and after treatment .Results The ef‐fective rate and sickness control rate of the observation group were 65 .9% and 79 .5% respectively ,which were higher than those in the control group ,and the differences were statistically significant (P0 .05) .The levels of liver and renal function indexes had no statistically significant differences between before and after treatment(P>0 .05) .Conclusion 3D‐CRT combined with DC‐CIK cell in the treatment of recurrent SCLC in high altitude regions has more obvious curative effect ,moreover has no obvious influence on radiotherapeutic adverse reactions ,and liver and renal functions .

Evolving Clinical Cancer Radiotherapy: Concerns Regarding Normal Tissue Protection and Quality Assurance

Radiotherapy, which is one of three major cancer treatment methods in modern medicine, has continued to develop for a long period, more than a century. The development of radiotherapy means allowing the administration of higher doses to tumors to improve tumor control rates while minimizing the radiation doses absorbed by surrounding normal tissues through which radiation passes for administration to tumors, thereby reducing or removing the incidence of side effects. Such development of radiotherapy was accomplished by the development of clinical radiation oncology, the development of computers and machine engineering, the introduction of cutting-edge imaging technology, a deepened understanding of biological studies on the effects of radiation on human bodies, and the development of quality assurance (QA) programs in medical physics. The development of radiotherapy over the last two decades has been quite dazzling. Due to continuous improvements in cancer treatment, the average five-year survival rate of cancer patients has been close to 70%. The increases in cancer patients' complete cure rates and survival periods are making patients' quality of life during or after treatment a vitally important issue. Radiotherapy is implemented in approximately 1/3 to 2/3s of all cancer patients; and has improved the quality of life of cancer patients in the present age. Over the last century, as a noninvasive treatment, radiotherapy has unceasingly enhanced complete tumor cure rates and the side effects of radiotherapy have been gradually decreasing, resulting in a tremendous improvement in the quality of life of cancer patients.

Dosimetric evaluation and clinical outcome in post-operative patients of carcinoma vulva treated with intensity-modulated radiotherapy.

BACKGROUND: To compare dosimetric parameters of intensity‑modulated radiation therapy (IMRT) with 3D conformal radiotherapy (3DCRT) in post‑operative patients of vulvar cancer and to assess clinical outcome and toxicity with IMRT. MATERIALS AND METHODS: A total of 8 post‑operative patients of vulvar cancer were treated with IMRT. All patients were also planned by 3DCRT for comparison with IMRT. The two plans were compared in terms of conformity index, homogeneity index, tumor control probability (TCP) and normal tissue complication probability (NTCP) for the planning target volume and organs at risk (OAR). RESULTS: IMRT resulted in significantly lesser doses to rectum, bladder, bowel and femoral head as compared with 3DCRT plans. Mean conformity and homogeneity indices were better and within range with IMRT. The TCP was comparable between the two treatment plans and NTCP for rectum, bladder, bowel and femoral head was significantly less with IMRT as compared with 3DCRT. Treatment was well‑tolerated and none of the patients developed Grade 3 or higher toxicity. CONCLUSION: IMRT yielded superior plans with respect to target coverage, homogeneity and conformality while lowering dose to adjacent OAR as compared with 3DCRT. Thus, IMRT offers a reduction in NTCP while maintaining TCP.

A margin from the clinic target volume to the planning target volume for esophagus carcinoma / 实用医学杂志

Objective To measure the setup errors and organ movements of patients with esophagus carcinoma during radiotherapy and find a reasonable margin from the clinic target volume (CTV) to the planning target volume (PTV). Methods (1) Set-up veri cation: Forty-two cases of untreated esophageal cancer were enrolled into this study. The physicist firstly made the planning according to the doctor requests and ensured the best distribution at the target. Thereafter, the 0° and 90° digitally reconstructed radiograph (DRR) was transmitted to the iView GT workshop. Meanwhile, two copies of cross-cut electronic portal image (EPI) were required before radiotherapy. Two doctors confirmed the variance of the osteal mark from the EPI and DRR,and output a 3D direction (left to right, superior to inferior, anterior to posterior) of the setup errors through the iView GT software. (2)Breathing motion:Ten cases of untreated esophageal cancer were enrolled into this study.Three distinct breathing levels were deflned: FB (free breathing), EBH (expiration with breath-held) and IBH (inspiration with breath-held). We gave the treatment planning in FB, then by moving the isocenter to EBH and IBH, we recalculated the dose distribution without changing the field angle, shape and weighing (Mus). Displacements were analyzed at four points (anterior, posterior, right lateral and left lateral) and five levels of target (upper, quarter, isocenter, three-quarter and lower). Results (1) The systematic setup errors were -0.23 cm, -0.02 cm and -0.06 cm, and the random errors were 0.44 cm, 0.45 cm and 0.44 cm at the direction of left to right(LR), superior to inferior (SI), anterior to posterior(AP), respectively. (2) The organ movements were 0.3 cm, 0.6cm and 0.3cm at the LR, SI, AP, respectively. Conclusions As an alternative, the root-sum-of-squares of set-up error and organ motion are suggested by σtot=√ (σITV2+σSM2). The CTV to PTV margins are 0.8cm left to right, 0.78cm superior to inferior, 0.5cm anterior to posterior.

Advances in treatment of radiation of non-small-cell lung cancer in the 15th World Conference on Lung Cancer / 肿瘤研究与临床

The 15th World Conference on Lung Cancer (WCLC) received about 210 abstracts on radiotherapy.These abstracts covered many realms,including the efficacy,safety,evaluation methods and dose fractionation study of stereotactic body radiotherapy (SBRT) on early stage non-small-cell lung cancer (NSCLC); control studies of high and standard radiation dose,different chemotherapy regimens and whether combined cetuximab in concurrent radiochemotherapy on locally advanced NSCLC clinical significance of postoperative 3D-conformal radiotherapy (3D-CRT) for patients with p Ⅲ A-N2 NSCLC after complete resection; the efficacy and safety of TKIs in combination with whole brain radiation therapy (WBRT) in NSCLC patients with multiple brain metastases,as well as the influence of EGFR mutation status on the curative effect.Besides,there are many reports about radiotherapy protection,toxicity,efficacy,prognosis and life quality assessment.

Comparison of 3D conformal radiotherapy with conventional radiotherapy in gliomas on dosimetry and prognosis / 重庆医学

Objective In contrast to conventional radiotherapy ,analyze the dosimetry and prognosis of 3D conformal radiothera-py in the treatment of gliomas with different pathological stages .Methods 97 patients with gliomas were selected ,and divided into two groups as conventional radiotherapy group (CR group) and 3D conformal radiotherapy group(3D group) .analyzed the influence of different radiotherapy to the gliomas in the same pathological stage .Compared the dosimetry differences between these two radio-therapies .Results There was no obvious differences in 3 year survival rate between CR group and 3D group at low grade gliomas . But 3D group had better 3 year survival rate than CR group at high grade gliomas .And 3D group had lower rate of relevant sequel after radiotherapy .3D group had higher conformal index (CI) and average dosage of radiation than CR group .Conclusion 3D radio-therapy has better dosimetry and conformal index than conventional radiotherapy ,especially has better prognosis in high grade glio-mas and lower rate of relevant sequel after radiotherapy .

Radioterapia de intensidad modulada (imrt) / Intensity modulation radiation therapy (imrt)

La radioterapia es un tratamiento efectivo en el manejo del cáncer. Es responsable de mejorar significativamente el control locorregional, la supervivencia global y la calidad de vida en múltiples tumores. Históricamente, sin embargo, sus complicaciones agudas y crónicas han reducido estos beneficios. La incorporación de la computación a la radioterapia ha permitido el desarrollo de diversas técnicas de tratamiento, incluyendo la radioterapia conformada 3D (3D-CRT) y la intensidad modulada (IMRT). Éstas permiten aumentar la dosis tumoral protegiendo los tejidos sanos, con un potencial aumento en el control del tumor y reducción de las complicaciones agudas y crónicas asociadas. Múltiples estudios prospectivos y retrospectivos han evaluado los beneficios de la IMRT en distintos tumores primarios. Hasta ahora sus principales indicaciones son cáncer de próstata y de cabeza y cuello. En otras localizaciones se han obtenido mejorías dosimétricas significativas. Se requiere mayor seguimiento para conocer los resultados clínicos tardíos de esta tecnología.

Radiation therapy is an effective treatment in cancer management. It is responsible for significant improvements in local/regional control, overall and cause-specific survival and better quality of life in many tumors. Nevertheless, in the past, acute and chronic radiation toxicity has reduced this benefits. The introduction of computer technologies to radiotherapy has allowed the development of various planning and treatment techniques, including 3D conformal radiotherapy (3D-CRT) and intensity modulation (IMRT), permiting to escalate tumor doses while protecting healthy tissues. This can improve tumor control and reduce acute and late complication rates associated with radiotherapy. Multiple prospective and retrospective studies have evaluated the benefits of IMRT in different primary tumors. Their main indications are head and neck and prostate cancer. In other locations, a significant dosimetric improvements of IMRT have been found, but longer follow-up is required to identify long term effects.

Analysis of short-term efficacy of 3D conformal radiotherapy for late-stage pancreatic cancer / 中华肝胆外科杂志

Objective To investigate the efficacy of 3D conformal radiotherapy for late-stage pancreatic cancer and determine relavent prognostic factors.Methods Fifty patients with advanced pancreatic cancer were divided into 3 groups according to treatment planning: palliative radiotherapy (group A) at 10.8-56 Gy, radiotherapy alone (group B) at 8-60.5 Gy and concurrent chemoradiother-apy (group C) at 10-64 Gy.All patients received 3D-conformal radiotherapy, and smaller multiple ports were used for palliative treatment whereas large fields including pancreatic tumors and adjacent lymph node drainage system were adopted in the beginning of radiotherapy.Concurrent chemotherapy with gemcitabine (200-600 mg/m~2) alone was used with weekly protocol.Results The duration of follow-up was 3-35 months.Forty three patients died during the follow-up for multiple metastasis, de-teriation, secondary infection and hemorrhage.Among the seven surviving patients, 3 received concur-rent radiotherapy, 3 radiotherapy alone and 1 palliative radiotherapy.Only 1 patient was alive in group A.However, the symtoms were relieved in 46% of the patients.The median survival time was 5.07 months whereas it was 4.33 months for patients received less than 45 Gy and 7.33 months for patients received 45 Gy or more.Three patients were alive in group B and the symptoms were relieved in 81% of the patients.The median survival time was 6.65 months whereas it was 4.36 months for patients received less than 45 Gy and 8.33 months for patients received 45 Gy or more.Three patients were a-live in group C and the symptoms were relieved in 89% of the patients.The median survival time was 9.89 months.One patient survived for 3 months after 8 Gy irradiation.The median survival time was 10.73 months for patients received 45 Gy or more.Conclusion 3D-conformal radiotherapy is safe and effective in treatment of advanced pancreatic cancer.The symptom relieving rate and median survival time seem to be related to patient's status, extent of disease, choice of treatment and irradiation dos-age.3D-confromal concurrent chemoradiotherapy leads to the longest survival time in some patients.

Evaluation of respiration-induced target volume motion in three-dimensional conformal radiotherapy(3D-CRT)for mid-thoracic esophageal carcinoma / 中华放射医学与防护杂志

Objective To evaluate the respiration-induced target volume motion in 3D-CRT for mid-thoracic esophageal carcinoma in order to guide the radiation oncologist to choose the expansion marginfor ITV.Methods Ten patients with mid-thoracic esophageal carcinoma were scanned by multi-spiral CTsimulator respectively in free breathing(FB),breath.hold after normal inspiration and expiration(IBH and EBH)with the same scanning range.Then the CT images of three series were transfefred to the treatmentplanning system.The target volume was outlined following the same standard.The motion of the centerpoint of GTV,the center point of each slice of GTV and the edge of the GTV in selected slice weremeasured respectively to obtain the comprehensive value of GTV motion。in order to find the appropriate IMvalue according to the 95％confidence interval of the GTV motion.Results①The GTV motion betweenIBH and EBH was(0.19±0.16)cm in the left.right direction,(0.54±0.19)cm in the cranial andcaudal irection.and(0.16±0.14)cm in anterior.posterior directions for the center of GTV,.For thecenter point of each slice of GTV.they ere(0.19±0.15)cm,(0.54±0.16)cm,(0.16±0.13)cm in three directions above.respectively.For the edge of the GTV in selected slice.they were(0.26±0.19)cm,(0.54±0.18)cm,(0.24±0.19)cm,respectively.The comprehensive value of GTV motion between IBH and EBH was(0.23±0.17)cm,(0.54±0.17)cm,(0.21±0.17)cm.respectively.The 95％confidence interval was 0.21-0.25 cm.0.53-0.56 cm and 0.19-0.22 cm in three directions.②The direction of GTV motion：No motion was noticed in 8.2％.while 73.3％to the right side and 18.5％to the left side in the left-right direction when IBH were compared with EBH.100％were moved to caudal in the the cranial and caudal direction[(0.54±0.17)cm].In the anterior-posterior direction,no motion was noticed in 8.2％,while 16.6％to the posterior and 75.2％to the anterior when IBH were compared with EBH.③The GTV motion was correlated with the vafiance of 1ung volumes in IBH-EBH(r=0.683,P=0.032)and not with GTV volume and length.Conclusions Respiration can induce target volume motion in 3 DCRT for mid-thoracic esophageal carcinoma.Compared to EBH.the GTV tends to move to the caudal,the anterior and the ight side in IBH.

Evaluation of respiration-induced dosimetric variance in three-dimensional conformal radiotherapy (3DCRT) for mid-thoracic esophageal carcinoma / 中华放射医学与防护杂志

Objective To evaluate the respiration-induced dosimetric variance in 3DCRT for midthoracic esophageal carcinoma, in order to guide the radiation oncologist to choose the expansion margin. Methods Ten patients with mid-thoracic esophageal carcinoma were scanned by multi-spiral CT simulator respectively in free breathing ( FB), breath-hold after normal inspiration and expiration ( IBH and EBH )with the same scanning range. Then the CT images of three series were transferred to the treatment planning system. The target volume was outlined following the same standard. Plan1 was designed in the images of FB and transported completely to the images of IBH and EBH as Plan2 and Plan3 respectively to observe the dosimetric variance in target volume. Results For GTV, there was a statistical difference only in V100 of the three plans ( H = 6.423, P = 0.040 ) and no significant difference was found in other indexes. For CTV, the V100 and V95 were better in Plan1 (F=3.992, P=0.030; H=9.920, P=0.007) and no significant difference was found in other indexes. While ()TV, the Dmin, V100 and V95 was better in Plan1 ( F = 3.677, P = 0.039; F = 4.539, P = 0.020; H = 6.846, P = 0.033 ) and no significant difference was found in other indexes. There were no significant differences in all the indexes for the spinal cord and lung in the three plans. Conclusions The change in dose distribution was not so much with the standard expansion. It can meet the needs of clinical treatment.

Positional Reproducibility and Effects of a Rectal Balloon in Prostate Cancer Radiotherapy

Despite the increasing use of the rectal balloon in prostate cancer radiotherapy, many issues still remain to be verified objectively including its positional reproducibility and relevance to treatment morbidity. We have developed a custom rectal balloon that has a scale indicating the depth of insertion and dilates symmetrically ensuring positional reproducibility. Fifty patients with prostate cancer treated by definitive 3D-conformal radiotherapy (3D-CRT) or intensity-modulated radiotherapy (IMRT) with rectal balloon were analyzed. Each of first five patients undergone computed tomography (CT) three times with a rectal balloon. The positional reproducibility was tested by Intraclass Correlation Coefficient (ICC) from the CT-to-CT fusion images. Planning variables and clinical acute toxicities were compared between when or not applying balloon. An ICC of greater than 0.9 in all directions revealed an excellent reproducibility of the balloon. Rectal balloon improved considerably the mean dose and V(45Gy)-V(65Gy) in plan comparison, and especially in 3D-CRT the rectal volume exposed to more than 60 Gy dropped from 41.3% to 19.5%. Clinically, the balloon lowered acute toxicity, which was lowest when both the balloon and IMRT were applied simultaneously. The rectal balloon carries excellent reproducibility and reduces acute toxicity in 3D-CRT and IMRT for prostate cancer.

Lack of the Difference in Outcome between N2 and N3 Non-Small Cell Lung Cancer Patients Treated with Concurrent Chemoradiotherapy; A Retrospective Analysis of 186 Patients

PURPOSE: To evaluate the difference in the patterns of failure and treatment for the outcomes of concurrent chemoradiotherapy, between clinical stage N2 and N3, in locally advanced unresectable stage III non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Between 1993 and 2000, 186 patients with gross mediastinal node positive non-small cell lung cancer, received concurrent chemoradiation therapy. The median follow-up period was 13 months, ranging from 1 to 65 months. The patterns of failure and treatment of outcomes of N2 and N3 were retrospectively analyzed. RESULTS: There were 170 men and 16 women, with an approximate man : woman ratio of 10 : 1. The median age of the patients was 60 years, ranging from 37 to 76 years. The numbers of patients with N2 and N3 stages were 90 and 96, respectively. Supraclavicular node metastasis was seen in 39 patients. Progression free survival rates of the N2 and N3 stages were 58% and 45%, respectively. The overall survival rates of the N2 and N3 stages were 34% and 27%, respectively. There were no statistically significant differences in progression free and overall survival rates between the two groups. There were statistically significant differences in the overall and progression free survival rates in relation to the supraclavicular lymph node positivity. Locoregional failure within radiation fields was the major pattern of failure. CONCLUSION: There were no differences in the patterns of failure and treatment outcomes with concurrent chemoradiation treatment. However, in this study, patients with supraclavicular node metastasis were considered to have an incurable disease. Therefore, a further investigation of the treatment scheme will be required in these cases.

Comparison of conventional and conformal radiotherapy and different irradiation technique by 3D-TPS for esophageal carcinoma : a dosimetric study / 中国癌症杂志

Purpose:To obtain the optimum irradiation technique in different plans of conventional radiotherapy(2DRT)and conformal radiotherapy(3DCRT)and between different conformal radiotherapy techniques for esophageal carcinoma as compared by 3D-TPS.Methods:10 patients with esophageal carcinoma were enrolled in this study.The conventional treatment plan and four conformal technique plans were created for each patient.Plan 1 was the same as the 2DRT,plan 2 consisted of anterior and two posterior oblique fields,plan 3 consisted of posterior and two anterior oblique fields,plan 4 consisted of 2 dynamic arc fields.Different plans were compared using DVH.Results:①On average,PTV of 2DRT was the same as that of 3DCRT in DVH.The difference in maximum dose to spinal cord was obvious.The left lung dose in D_(mean)?D_(min)?V_(30) in 2DRT was significantly increased as compared to 3DCRT(P

Dose Planning of Forward Intensity Modulated Radiation Therapy for Nasopharyngeal Cancer using Compensating Filters / 대한방사선종양학회지

PURPOSE: To improve the local control of patients with nasopharyngeal cancer, we have implemented 3-D conformal radiotherapy and forward intensity modulated radiation therapy (IMRT) to used of compensating filters. Three dimension conformal radiotherapy with intensity modulation is a new modality for cancer treatments. We designed 3-D treatment planning with 3-D RTP (radiation treatment planning system) and evaluation dose distribution with tumor control probability (TCP) and normal tissue complication probability (NTCP). MATERIALS AND METHODS: We have developed a treatment plan consisting four intensity modulated photon fields that are delivered through the compensating filters and block transmission for critical organs. We get a full size CT imaging including head and neck as 3 mm slices, and delineating PTV (planning target volume) and surrounding critical organs, and reconstructed 3D imaging on the computer windows. In the planning stage, the planner specifies the number of beams and their directions including non-coplanar, and the prescribed doses for the target volume and the permissible dose of normal organs and the overlap regions. We designed compensating filter according to tissue deficit and PTV volume shape also dose weighting for each field to obtain adequate dose distribution, and shielding blocks weighting for transmission. Therapeutic gains were evaluated by numerical equation of tumor control probability and normal tissue complication probability. The TCP and NTCP by DVH (dose volume histogram) were compared with the 3-D conformal radiotherapy and forward intensity modulated conformal radiotherapy by compensator and blocks weighting. Optimization for the weight distribution was performed iteration with initial guess weight or the even weight distribution. The TCP and NTCP by DVH were compared with the 3-D conformal radiotherapy and intensitiy modulated conformal radiotherapy by compensator and blocks weighting. RESULTS: Using a four field IMRT plan, we have customized dose distribution to conform and deliver sufficient dose to the PTV. In addition, in the overlap regions between the PTV and the normal organs (spinal cord, salivary grand, pituitary, optic nerves), the dose is kept within the tolerance of the respective organs. We evaluated to obtain sufficient TCP value and acceptable NTCP using compensating filters. Quality assurance checks show acceptable agreement between the planned and the implemented MLC (multi-leaf collimator). CONCLUSION: IMRT provides a powerful and efficient solution for complex planning problems where the surrounding normal tissues place severe constraints on the prescription dose. The intensity modulated fields can be efficaciously and accurately delivered using compensating filters.