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Dysphagia in head and neck cancer patients following intensity modulated radiotherapy (IMRT)
Evangelia Peponi, Christoph Glanzmann, Bettina Willi, Gerhard Huber, Gabriela Studer
Radiation Oncology , 2011, DOI: 10.1186/1748-717x-6-1
Abstract: 82 patients with stage III/IV squamous cell carcinoma of the larynx, oropharynx, or hypopharynx, who underwent successful definitive (n = 63, mean dose 68.9Gy) or postoperative (n = 19, mean dose 64.2Gy) simultaneous integrated boost (SIB) -IMRT either alone or in combination with chemotherapy (85%) with curative intent between January 2002 and November 2005, were evaluated retrospectively. 13/63 definitively irradiated patients (21%) presented with a total gross tumor volume (tGTV) >70cc (82-173cc; mean 106cc). In all patients, a laryngo-pharyngeal midline sparing contour outside of the PTV was drawn. Dysphagia was graded according subjective patient-reported and objective observer-assessed instruments. All patients were re-assessed 12 months later. Dose distribution to the swallowing structures was calculated.At the re-assessment, 32-month mean post treatment follow-up (range 16-60), grade 3/4 objective toxicity was assessed in 10%. At the 32-month evaluation as well as at the last follow up assessment mean 50 months (16-85) post-treatment, persisting swallowing dysfunction grade 3 was subjectively and objectively observed in 1 patient (1%). The 5-year local control rate of the cohort was 75%; no medial marginal failures were observed.Our results show that sparing the swallowing structures by IMRT seems effective and relatively safe in terms of avoidance of persistent grade 3/4 late dysphagia and local disease control.Limited data are available on the long term swallowing function in intensity modulated radiotherapy (IMRT) treated patients at risk for dysphagia [1-3].We aimed to evaluate the objective and subjective long term swallowing function, and to relate dysphagia to the radiation dose delivered to the critical anatomical structures in our consecutively IMRT (+/- chemotherapy) treated head and neck cancer patients.We focused on serious subjective as well as objective symptoms (grade 3/4 late effects).A total of 82 out of 96 eligible patients 'at risk' for dy
Intensity Modulated Radiotherapy (IMRT) and Fractionated Stereotactic Radiotherapy (FSRT) for children with head-and-neck-rhabdomyosarcoma
Stephanie E Combs, Wolfgang Behnisch, Andreas E Kulozik, Peter E Huber, Jürgen Debus, Daniela Schulz-Ertner
BMC Cancer , 2007, DOI: 10.1186/1471-2407-7-177
Abstract: We treated 19 children with head-and-neck rhabdomyosarcoma with FSRT (n = 14) or IMRT (n = 5) as a part of multimodal therapy. Median age at the time of radiation therapy was 5 years (range 2–15 years). All children received systemic chemotherapy according to the German Soft Tissue Sarcoma Study protocols.Median size of treatment volume for RT was 93,4 ml. We applied a median total dose of 45 Gy (range 32 Gy – 54 Gy) using a median fractionation of 5 × 1,8 Gy/week (range 1,6 Gy – 1,8 Gy).The median time interval between primary diagnosis and radiation therapy was 5 months (range 3–9 months).After RT, the 3- and 5-year survival rate was 94%. The 3- and 5-year actuarial local control rate after RT was 89%.The actuarial freedom of distant metastases rate at 3- and 5-years was 89% for all patients.Radiotherapy was well tolerated in all children and could be completed without interruptions > 4 days. No toxicities >CTC grade 2 were observed. The median follow-up time after RT was 17 months.IMRT and FSRT lead to excellent outcome in children with head-and-neck RMS with a low incidence of treatment-related side effects.Rhabdomyosarcoma (RMS) is the most common soft tissue sarcoma entity in children [1]. The most common sites of RMS in children are the head and neck region (35%), the genitourinary tract (35%) and the extremities (17%) [2]. The orbit is the primary site in about 10% of these tumors, the most common localization in the head and neck area is parameningeal, including the nasopharynx, the paranasal sinuses, the middle ear and mastoid and the infratemporal fossa/pterygopalatine space [2-8]. Most children are younger than 10 years of age (72%) [9].Modern therapy protocols comprise of surgical resection, chemotherapy and radiotherapy (RT). However, RT in children is commonly applied cautiously with respect to early and late side effects [10-14].With modern RT techniques such as Intensity Modulated Radiotherapy (IMRT) and Fractionated Stereotactic Radiotherapy (FSRT)
The technical feasibility of an image-guided intensity-modulated radiotherapy (IG-IMRT) to perform a hypofractionated schedule in terms of toxicity and local control for patients with locally advanced or recurrent pancreatic cancer  [cached]
Son Seok,Song Jin,Choi Byung,Kang Young-nam
Radiation Oncology , 2012, DOI: 10.1186/1748-717x-7-203
Abstract: Background The purpose of this study was to evaluate the technical feasibility of an image-guided intensity modulated radiotherapy (IG-IMRT) using involved-field technique to perform a hypofractionated schedule for patients with locally advanced or recurrent pancreatic cancer. Methods From May 2009 to November 2011, 12 patients with locally advanced or locally recurrent pancreatic cancer received hypofractionated CCRT using TomoTherapy Hi-Art with concurrent and sequential chemotherapy at Seoul St. Mary’s Hospital, the Catholic University of Korea. The total dose delivered was 45 Gy in 15 fractions or 50 Gy in 20 fractions. The target volume did not include the uninvolved regional lymph nodes. Treatment planning and delivery were performed using the IG-IMRT technique. The follow-up duration was a median of 31.1 months (range: 5.7-36.3 months). Results Grade 2 or worse acute toxicities developed in 7 patients (58%). Grade 3 or worse gastrointestinal and hematologic toxicity occurred in 0% and 17% of patients, respectively. In the response evaluation, the rates of partial response and stable disease were 58% and 42%, respectively. The rate of local failure was 8% and no regional failure was observed. Distant failure was the main cause of treatment failure. The progression-free survival and overall survival durations were 7.6 and 12.1 months, respectively. Conclusion The involved-field technique and IG-IMRT delivered via a hypofractionated schedule are feasible for patients with locally advanced or recurrent pancreatic cancer.
Inverse planned stereotactic intensity modulated radiotherapy (IMRT) in the treatment of incompletely and completely resected adenoid cystic carcinomas of the head and neck: initial clinical results and toxicity of treatment
MW Münter, D Schulz-Ertner, H Hof, A Nikoghosyan, A Jensen, S Nill, P Huber, J Debus
Radiation Oncology , 2006, DOI: 10.1186/1748-717x-1-17
Abstract: 25 patients with huge ACC in different areas of the head and neck were treated. At the time of radiotherapy two patients already suffered from distant metastases. A complete resection of the tumor was possible in only 4 patients. The remaining patients were incompletely resected (R2: 20; R1: 1). 21 patients received an integrated boost IMRT (IBRT), which allow the use of different single doses for different target volumes in one fraction. All patients were treated after inverse treatment planning and stereotactic target point localization.The mean folllow-up was 22.8 months (91 – 1490 days). According to Kaplan Meier the three year overall survival rate was 72%. 4 patients died caused by a systemic progression of the disease. The three-year recurrence free survival was according to Kaplan Meier in this group of patients 38%. 3 patients developed an in-field recurrence and 3 patient showed a metastasis in an adjacent lymph node of the head and neck region. One patient with an in-field recurrence and a patient with the lymph node recurrence could be re-treated by radiotherapy. Both patients are now controlled. Acute side effects >Grade II did only appear so far in a small number of patients.The inverse planned stereotactic IMRT is feasible in the treatment of ACC. By using IMRT, high control rates and low side effects could by achieved. Further evaluation concerning the long term follow-up is needed. Due to the technical advantage of IMRT this treatment modality should be used if a particle therapy is not available.Adenoid cystic carcinomas of the head and neck are a unique kind of tumour deriving from cells of the major and minor salivary glands, they account for 25% of all malignant salivary gland tumours in different series. Although ACCs are the most common histological type of tumours in the minor salivary glands with a total of 55% [1] they account for only about 10–15% of all parotid gland malignancies. ACCs can be shown to be unique for various reasons: first
The role of intensity-modulated radiotherapy in head and neck cancer  [cached]
Bhide S,Kazi R,Newbold K,Harrington K
Indian Journal of Cancer , 2010,
Abstract: Intensity-modulated radiotherapy (IMRT) has been a significant technological advance in the field of radiotherapy in recent years. IMRT allows sparing of normal tissue while delivering radical radiation doses to the target volumes. The role of IMRT for parotid salivary gland sparing in head and neck cancer is well established. The utility of IMRT for pharyngeal constrictor muscle and cochlear sparing requires investigation in clinical trials. The current evidence supporting the use of IMRT in various head and neck subsites has been summarized. Sparing of organs at risk allows for dose-escalation to the target volumes, taking advantage of the steep dose-response relationship for squamous cell carcinomas to improve treatment outcomes in advanced head and neck cancers. However, dose-escalation could result in increased radiation toxicity (acute and late), which has to be studied in detail. The future of IMRT in head and neck cancers lies in exploring the use of biological imaging for dose-escalation using targeted dose painting.
Dose-Escalated Hypofractionated Intensity-Modulated Radiotherapy in High-Risk Carcinoma of the Prostate: Outcome and Late Toxicity  [PDF]
David Thomson,Sophie Merrick,Ric Swindell,Joanna Coote,Kay Kelly,Julie Stratford,James Wylie,Richard Cowan,Tony Elliott,John Logue,Ananya Choudhury,Jacqueline Livsey
Prostate Cancer , 2012, DOI: 10.1155/2012/450246
Abstract: Background. The benefit of dose-escalated hypofractionated radiotherapy using intensity-modulated radiotherapy (IMRT) in prostate cancer is not established. We report 5-year outcome and long-term toxicity data within a phase II clinical trial. Materials and Methods. 60 men with predominantly high-risk prostate cancer were treated. All patients received neoadjuvant hormone therapy, completing up to 6 months in total. Thirty patients were treated with 57?Gy in 19 fractions and 30 patients with 60?Gy in 20 fractions. Acute and 2-year toxicities were reported and patients followed longitudinally to assess 5 year outcomes and long-term toxicity. Toxicity was measured using RTOG criteria and LENT/SOMA questionnaire. Results. Median followup was 84 months. Five-year overall survival (OS) was 83% and biochemical progression-free survival (bPFS) was 50% for 57?Gy. Five-year OS was 75% and bPFS 58% for 60?Gy. At 7 years, toxicity by RTOG criteria was acceptable with no grade 3 or above toxicity. Compared with baseline, there was no significant change in urinary symptoms at 2 or 7 years. Bowel symptoms were stable between 2 and 7 years. All patients continued to have significant sexual dysfunction. Conclusion. In high-risk prostate cancer, dose-escalated hypofractionated radiotherapy using IMRT results in encouraging outcomes and acceptable late toxicity. 1. Introduction Dose-escalated radiotherapy improves local and biochemical disease control in localised prostate cancer [1–4]. However, this is at the expense of increased late normal tissue toxicity and overall treatment time [3–6].There is increasing evidence that the α/β ratio for prostate cancer may be low [7–9], and in one analysis of nearly 6000 patients the calculated α/β ratio was 1.4 [10]. This suggests that a hypofractionated regimen should be biologically advantageous. A shortened overall treatment time also provides benefits in terms of patient acceptability and health economics [11]. Our group has previously published data on patients treated with 50?Gy in 16 daily fractions (equivalent total dose of 66?Gy, assuming an α/β ratio for prostate cancer of 1.5) [12]. However, the biochemical outcome for patients with intermediate or high risk disease was inferior to dose-escalated series using 2?Gy per fraction [13]. This finding was replicated in a later study using low-dose hypofractionated radiotherapy [14]. Although there is evidence for improved bPFS with increasing doses of radiotherapy, no overall survival benefit has yet been demonstrated. Indeed, the MRC RT01 study showed equivalent overall
Integral dose to the carotid artery in intensity modulated radiotherapy of carcinoma nasopharynx: Extended field IMRT versus split-field IMRT  [cached]
Bahl A,Basu K.S.J.,Sharma D,Rath G
Journal of Cancer Research and Therapeutics , 2010,
Abstract: Aim : To evaluate the integral dose to carotid vessels in extended field intensity modulated radiotherapy (IMRT) (including the lower neck nodes in IMRT field) and split field IMRT (using separate single anterior field to treat lower neck nodes) in cancer nasopharynx. Materials and Methods : Dosimetric data from 10 patients of carcinoma nasopharynx, undergoing IMRT, were evaluated in this prospective study. The carotid vessels were contoured from sternoclavicular joints upto the base of skull. IMRT plans were generated for all patients with extended field and split field IMRT techniques using nine coplanar beams with 6 MV photons. A dose of 70 Gy to planning target volume (PTV) 70Gy , 59.4 Gy to PTV 59.4Gy and 54 Gy to PTV 54Gy was delivered in 33 fractions. The dose constraints were similar for both the techniques. The integral dose to the carotid arteries was calculated as the mean dose times the volume (mean dose Χ volume) in units of liter-gray. Results : The mean dose to the carotid vessels in the extended field IMRT was 63.88 ± 0.97 Gy (mean dose ± SD) and it was 64.43 ± 0.73 Gy for the split field technique. The integral dose in the extended field versus split field technique was 0.29 ± 0.0207 and 0.32 ± 0.0213 liter-gray, respectively. The difference was statistically significant (P < 0.013). Conclusions : Extended field IMRT delivers a slightly lower integral dose to carotid arteries in treatment of cancer nasopharynx while maintaining good dose homogeneity to the PTV 54Gy and can be preferred over split field radiotherapy.
Lhermitte's Sign Developing after IMRT for Head and Neck Cancer  [PDF]
Dong C. Lim,Patrick J. Gagnon,Sophia Meranvil,Darryl Kaurin,Linda Lipp,John M. Holland
International Journal of Otolaryngology , 2010, DOI: 10.1155/2010/907960
Abstract: Background. Lhermitte's sign (LS) is a benign form of myelopathy with neck flexion producing an unpleasant electric-shock sensation radiating down the extremities. Although rare, it can occur after head and neck radiotherapy. Results. We report a case of Lhermitte's developing after curative intensity-modulated radiotherapy (IMRT) for a patient with locoregionally advanced oropharyngeal cancer. IMRT delivers a conformal dose of radiation in head and neck cancer resulting in a gradient of radiation dose throughout the spinal cord. Using IMRT, more dose is delivered to the anterior spinal cord than the posterior cord. Conclusions. Lhermitte's sign can develop after IMRT for head and neck cancer. We propose an anterior spinal cord structure, the spinothalamic tract to be the target of IMRT-caused LS.
Comparison of intensity modulated radiotherapy (IMRT) with intensity modulated particle therapy (IMPT) using fixed beams or an ion gantry for the treatment of patients with skull base meningiomas
Katsura Kosaki, Swantje Ecker, Daniel Habermehl, Stefan Rieken, Oliver J?kel, Klaus Herfarth, Jürgen Debus, Stephanie E Combs
Radiation Oncology , 2012, DOI: 10.1186/1748-717x-7-44
Abstract: Five patients originally treated with photon IMRT were selected for the study. Ion beams were chosen using a horizontal beam or an ion gantry. Intensity controlled raster scanning and the intensity modulated particle therapy mode were used for plan optimization. The evaluation included analysis of dose-volume histograms of the target volumes and organs at risk.In comparison with carbon and proton beams only with horizontal beams, carbon ion treatment plans could spare the OARs more and concentrated on the target volumes more than proton and photon IMRT treatment plans. Using only a horizontal fixed beam, satisfactory plans could be achieved for skull base tumors.The results of the case studies showed that using IMPT has the potential to overcome the lack of a gantry for skull base tumors. Carbon ion plans offered slightly better dose distributions than proton plans, but the differences were not clinically significant with established dose prescription concepts.Treatment of skull base tumors is a challenge for the radiation oncologist. Optimization of dose distributions to complex target volumes has been a main goal over the last decades, and modern photon techniques such as Intensity Modulated Radiotherapy (IMRT) have significantly improved treatment of base of skull tumors. Histological subtypes in the skull base region include highly malignant tumors such as high-grade hemangiopericytomas, squamous cell carcinomas or sarcomas, but also benign lesions, such as meningiomas. In these patients, high local doses for tumor control are also required, however, also sparing of normal tissue to prevent treatment-related side effects impairing quality of life is of high importance.Several publications reported comparison studies in the head and neck region and the central nervous system using proton or carbon ion therapy as well as conventional and/or IMRT [1-8]. In photon treatments, a gantry is standard today and is necessary to obtain good dose distributions and conformit
Time trial: A prospective comparative study of the time-resource burden for three-dimensional conformal radiotherapy and intensity-modulated radiotherapy in head and neck cancers  [cached]
Murthy Vedang,Gupta Tejpal,Kadam Avinash,Ghosh-Laskar Sarbani
Journal of Cancer Research and Therapeutics , 2009,
Abstract: Introduction: An ongoing institutional randomized clinical trial comparing three-dimensional conformal radiotherapy (3D CRT) and intensity-modulated radiotherapy (IMRT) provided us an opportunity to document and compare the time-manpower burden with these high-precision techniques in head and neck cancers. Materials and Methods: A cohort of 20 consecutive patients in the ongoing trial was studied. The radiotherapy planning and delivery process was divided into well-defined steps and allocated human resource based on prevalent departmental practice. Person-hours for each step were calculated. Results: Twelve patients underwent IMRT and eight patients had 3D CRT. The prerandomization steps (upto and including approval of contours) were common between the two arms, and expectedly, the time taken to complete each step was similar. The planning step was carried out postrandomization and the median times were similar for 3D CRT (312 min, 5.2 person-hours) and IMRT (325.6 min, 5.4 person-hours). The median treatment delivery time taken per fraction varied between the two arms, with 3D CRT taking 15.2 min (0.6 person-hours), while IMRT taking 27.8 min (0.9 person-hours) (P< 0.001). The total treatment time was also significantly longer in the IMRT arm (median 27.7 versus 17.8 person-hours, P< 0.001). The entire process of IMRT took 48.5 person-hours while 3D CRT took a median of 37.3 person-hours. The monitor units delivered per fraction and the actual "beam-on" time was also statistically longer with IMRT. Conclusions: IMRT required more person-hours than 3D CRT, the main difference being in the time taken to deliver the step-and-shoot IMRT and the patient-specific quality assurance associated with IMRT.
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