Use Of Helical Tomotherapy Research Articles

Dose delivery accuracy on helical tomotherapy for 4-dimensional tumor motion - a phantom study.

BackgroundThe advances in image guidance and capability of highly conformal dose deliveries made possible the use of helical tomotherapy (HT) for lung cancer treatment. To determine the effect of respiratory motion on the delivered dose in HT, film dosimetry using a dynamic phantom was performed. This was a phantom study to determine the effect of motion on the delivered dose in HT.Materials and methods4D computed tomography (4DCT) was acquired for various target motions of CIRS dynamic phantom (CIRS Inc., Norfolk, USA) with 2.5cm diameter spherical target of volume 8.2 cc moving in the COS4 motion pattern. AveIP images and treatment plans were generated in the HT planning system. Target excursions during treatment delivery were changed in the superior-inferior, anteroposterior and lateral directions. The breathing cycle time was varied from 4 to 5 sec. and also the delivery interruptions were introduced. A film was exposed for each delivery and gamma analysis was performed.ResultsThe gamma pass rate (GPR) with 3%, 2 mm criteria for the target motion in the S-I direction showed a significant reduction from 97.5% to 54.4% as the motion increased from 3 mm to 8 mm (p = 0.03). For the target motion in S-I = 8 mm, L-R = A-P = 3 mm, the percentage decrease in the GPR was 74% (p = 0.001) for three interruptions.ConclusionThe ITV based approach in HT is ideal for a shallow breathing situation when the tumor excursions were confined to 5 mm in the S-I and 3 mm in L-R and A-P directions.

Gonadal-sparing total body irradiation with the use of helical tomotherapy for nonmalignant indications.

The aim was to demonstrate the feasibility and technique of gonadal sparing total body irradiation (TBI) with helical tomotherapy. Total body irradiation is a common part of the conditioning regimen prior to allogeneic stem cell transplantation. Shielding or dose-reduction to the gonads is often desired to preserve fertility, particularly in young patients undergoing transplant for non-malignant indications. Helical tomotherapy (HT) has been shown to be superior to traditional TBI delivery for organ at risk (OA R) doses and dose homogeneity. We present two representative cases (one male and one female) to illustrate the feasibility of this technique, each of whom received 3Gy in a single fraction prior to allogeneic stem cell transplant for benign indications. The planning target volume (PTV) included the whole body with a subtraction of OA Rs including the lungs, heart, and brain (each contracted by 1cm) as well as the gonads (testicles expanded by 5 cm and ovaries expanded by 0.5 cm). For the male patient we achieved a homogeneity index of 1.35 with a maximum and median planned dose to the testes of 0.53 Gy and 0.35 Gy, respectively. In-vivo dosimetry demonstrated an actual received dose of 0.48 Gy. For the female patient we achieved a homogeneity index of 1.13 with a maximum and median planned dose to the ovaries of 1.66 Gy and 0.86 Gy, respectively. Gonadal sparing TBI is feasible and deliverable using HT in patients with non-malignant diseases requiring TBI as part of a pre-stem cell transplant conditioning regimen.

Mycosis fungoides, insights in the latest therapy options and the possibility of a promising use of helical tomotherapy

Mycosis fungoides, insights in the latest therapy options and the possibility of a promising use of helical tomotherapy

Total marrow irradiation (TMI) combined with treosulfan and fludarabine conditioning regimen for chemosensitive advanced multiple myeloma (MM) patients undergoing matched allogeneic stem-cell transplantation: First results of a phase I/II prospective monocentric study (TrRaMM TMI).

e19019Background: Recent data support the use of Helical Tomotherapy to deliver radiation to target tissues, such as bone marrow, sparing vital organs in an effort to reduce toxicities. We report t...

The use of helical tomotherapy in the treatment of early stage breast cancer: indications, tolerance, efficacy-a single center experience.

Purposeto evaluate our experience in terms of local control, survival, adverse effects in patients treated by adjuvant helical tomotherapy (HT) for breast cancer (BC).ResultsWe studied 179 consecutive patients with 194 treated breasts with adjuvant HT. Median follow-up was 38.1 months. Median age was 53 years. Chemotherapy was administered to 83% of patients. All 133 hormone receptor positive tumours received hormonal therapy. As concurrent treatment, apart from trastuzumab monotherapy, 6 patients received systemic therapy concomitant to RT. The HT was generally well tolerated with mostly grade 1 and 2 skin reactions and esophagitis. Only 3% grade III early skin reactions. At last follow-up, there were 2 local recurrences, 1 regional lymph node (LN) recurrence and 6 with metastatic progression. The 5-year progression-free survival was 90.5% (95% CI 84.2–97.3).Materials and MethodsA retrospective study of all patients treated by HT between 2009 and 2015 was done. Patients excluded were those with: breast implants, advanced or metastatic BC, recurrent disease. All patients received breast+/-boost or chest wall irradiation and most received with LN irradiation. Dose constraints for organs at risk were defined using optimization scale developed in our Department. Evaluation of early and late toxicity was done using Common Terminology Adverse Criteria Events v.4.0.ConclusionsHT can be used for a well selected group of breast cancer as bilateral tumours, complex anatomy and target volumes where the conventional radiation therapy techniques cannot ensure an optimal dose distribution. Longer follow-up is necessary to confirm and validate these results.

Imaging findings associated with nasopharyngeal amyloidosis in an Arabian stallion

SummaryA 3‐year‐old Arabian stallion presented for imaging and further work‐up of nasal discharge and respiratory stridor secondary to nasal amyloidosis. Thickening of the nasal mucosa with heterogeneous attenuation of the affected tissues was identified on CT images. The nasal mucosa, mucosa of the arytenoid cartilages, and regional lymph nodes were hypointense on T2 and T1 MRI images with moderate, patchy contrast enhancement. Biopsy and histopathology of the nasal mucosa, mucosa of the arytenoid cartilages and regional lymph nodes confirmed the original diagnosis of amyloidosis. Six fractions of helical tomotherapy did not provide significant improvement in respiratory effort, and permanent tracheostomy was performed. Haemorrhagic nasal discharge and mucosal plaques in the nasal cavity, pharynx, larynx, and trachea worsened over a 19‐month interim. This paper offers the first description of the CT and MRI findings of nasopharyngeal amyloidosis in a horse, and the first description of the use of helical tomotherapy in an equine patient.

EP-2388: Use of helical tomotherapy for local treatment in metastatic breast cancer: single center experience

EP-2388: Use of helical tomotherapy for local treatment in metastatic breast cancer: single center experience

EP-1316: The use of Helical Tomotherapy in early stage breast cancer: indications, tolerance, efficacy

EP-1316: The use of Helical Tomotherapy in early stage breast cancer: indications, tolerance, efficacy

Use of helical tomotherapy in locally advanced and/or metastatic breast cancer for locoregional treatment.

Helical tomotherapy (HT) is a new promising tool whose use remains to be studied. This work assesses its impact for local irradiation in terms of side effects, as well as tumour control in locally advanced (LABC) and metastatic breast cancer (MBC). We retrospectively reviewed data of 66 patients with LABC and MBC. Patients received standard fractionated radiotherapy by HT, with or without concurrent systemic treatment. The median age was 60 years (28-77). The median follow-up of the population was 35.9 months (10.6-95.8). For 91% of patients, HT was concomitant with systemic treatments. Three patients experienced grade 3 skin toxicity and all had concurrent 5FU-vinorelbine. One patient who was receiving concurrent treatment with trastuzumab-pertuzumab had a decreased left ventricular ejection fraction by 14%. No late cardiac or lung toxicity was observed. A clinical benefit was observed in 75% of cases. At 2 months after HT, we observed tumour regression in 7/8 patients, as following: 1 complete, 4 partial responses, and 2 stable disease. The median survival for MBC group was 64.4 months (42.6-65.8) and 21.1 (6.1-36.1) months for LABC. This study suggests that the use of HT is well tolerated and feasible with a multimodal strategy that includes concurrent systemic treatments for patients with LABC and MBC. Advances in knowledge: The survival of LABC and MBC increases and new safe tools are needed to determine optimal strategies of treatment. To our knowledge, this is the first paper describing the use of HT for this population.

Techniques d’irradiation mammaire complexe : radiothérapie conformationelle tridimensionnelle mono-isocentrique et nomothérapie hélicoïdale

PurposeTo evaluate the dosimetric contribution of helical tomotherapy for breast cancers compared with conformal radiotherapy in mono-isocentric technique. Patients and methodFor 23 patients, the dosimetric results in mono-isocentric 3D conformational radiotherapy did not satisfy the constraints either of target volumes nor organs at risk. A prospective dosimetric comparison between mono-isocentric 3D conformational radiotherapy and helical tomotherapy was therefore carried out. ResultsThe use of helical tomotherapy showed a benefit in these 23 patients, with either an improvement in the conformity index or homogeneity, but with an increase in low doses. Of the 23 patients, two had pectus excavatum, five had past thoracic irradiation and two required bilateral irradiation. The other 14 patients had a combination of morphology and/or indication of lymph node irradiation. For these patients, helical tomotherapy was therefore preferred to mono-isocentric 3D conformational radiotherapy. ConclusionsTomotherapy appears to provide better homogeneity and tumour coverage. This technique of irradiation may be justified in the case of morphological situations such as pectus exavatum and in complex clinical situations. In other cases, conformal radiotherapy in mono-isocentric technique remains to be favoured.

Pediatric craniospinal irradiation with conventional technique or helical tomotherapy: impact of age and body volume on integral dose.

The use of helical tomotherapy (HT) for craniospinal irradiation (CSI) in pediatric patients remains an issue of discussion. In this study, we evaluated the integral dose (ID) to organs at risk (OARs) and to the whole body delivered with conventional 3-dimensional conformal radiotherapy (3D-CRT) and HT for pediatric patients and made a comparison according to different whole body volumes. We selected 10 pediatric patients with different body volumes and of different ages undergoing CSI. Plans for 3D-CRT and HT were developed for each patient. The ID to OARs and to the whole body were compared and statistical analyses were performed to determine differences. We noticed that variations of ID depend on the different anatomical location of the organs relatively to the target, with lower ID to OARs opposed to the target and increased ID to lateral organs: ID tomotherapy/3D-CRT ratio was higher in lungs, kidneys, and mammary region, while it was lower in heart, liver, thyroid, and esophagus. The ID of the body increased with large volumes both in HT and in 3D-CRT plans, but in tomotherapy plans ID increased significantly more with large volumes than with small ones. While there are no differences in using tomotherapy or 3D-CRT with small body volumes, we found a difference with large volumes (≥20,000 mL vs ≤20,000 mL). Therefore, for very small patients, the use of intensity-modulated radiotherapy provided with tomotherapy to reduce the dose to OARs can be reconsidered.

Radiation pneumonitis in non-small-cell lung cancer patients treated with helical tomotherapy.

In this study, we investigated the incidence of radiation pneumonitis (RP) in non-small-cell lung cancer (NSCLC) patients undergoing helical tomotherapy (HT) and the clinical and dosimetric factors associated with it. We analyzed data from the treatment protocols of 62 NSCLC patients. The median total radiation dose was 64 Gy (range 57.6-66 Gy) at 1.8-2.2 Gy/fraction. Thirty-four of these patients underwent HT alone and 28 underwent HT in combination with chemotherapy. Treatment-related pneumonitis was graded according to the Common Terminology Criteria for Adverse Events, version 3.0. We found that RP grades 1, 2, 3 and 5 occurred in 29 (46.8%), 23 (37.1%), 8 (12.9%), and 2 (3.2%) patients, respectively. Using univariate analyses, we found that a grade ≥3 RP was associated with poor performance status (PS), age, planning target volume, mean lung dose, and relative V5through V25, in increments of 5 Gy (P < 0.005). We determined that PS and V5V15were the most significant factors associated with grade ≥3 RP using multivariate analysis. We found that poor PS and V5-V15 were the risk factors associated with grade ≥3 RP in NSCLC patients treated with HT. Thus, for NSCLC patients treated with HT, the volume of total lung with low-dose region (V5-V15) should be carefully regulated and the use of HT should be restricted in patients with Eastern Cooperative Oncology Group ≥2.

Helical tomotherapy in head and neck cancer: a European single-center experience.

We report on a retrospective analysis of 147 patients with early and locoregionally advanced squamous cell head and neck cancer (SCCHN) treated with helical tomotherapy (HT). Included were patients with SCCHN of the oral cavity (OC), oropharynx (OP), hypopharynx (HP), or larynx (L) consecutively treated in one radiotherapy center in 2008 and 2009. The prescribed HT dose was 60-66 Gy in the postoperative setting (group A) and 66-70 Gy when given as primary treatment (group B). HT was given alone, concurrent with systemic therapy (ST), that is, chemotherapy, biotherapy, or both, and with or without induction therapy (IT). Acute and late toxicities are reported using standard criteria; locoregional failure/progression (LRF), distant metastases (DM), and second primary tumors (SPT) were documented, and event-free survival (EFS) and overall survival (OS) were calculated from the start of HT. Group A patients received HT alone in 22 cases and HT + ST in 20 cases; group B patients received HT alone in 17 cases and HT + ST in 88 cases. Severe (grade ≥ 3) acute mucosal toxicity and swallowing problems increased with more additional ST. After a median follow-up of 44 months, grade ≥2 late toxicity after HT + ST was approximately twice that of HT alone for skin, subcutis, pharynx, and larynx. Forty percent had grade ≥2 late xerostomia, and 29% had mucosal toxicity. At 3 years, LRF/DM/SPT occurred in 7%/7%/17% and 25%/13%/5% in groups A and B, respectively, leading to a 3-year EFS/OS of 64%/74% and 56%/63% in groups A and B, respectively. The use of HT alone or in combination with ST is feasible and promising and has a low late fatality rate. However, late toxicity is nearly twice as high when ST is added to HT.

Use of Helical TomoTherapy for the Focal Hypofractionated Treatment of Limited Brain Metastases in the Initial and Recurrent Setting.

Background: Whole-brain radiation therapy (WBRT), stereotactic radiosurgery (SRS), or both are commonly employed in the treatment of limited brain metastases in the initial or recurrent setting. Hypofractionated partial volume irradiation is also employed, however, published experience using helical TomoTherapy (HT) for this purposes is limited. We reviewed our institutional experience to assess patient selection factors, fractionation scheme, and outcomes associated with this technique.Methods: A retrospective chart review was performed to evaluate patients treated with partial volume hypofractionated HT-based IMRT for brain metastases at our institution.Results: Thirteen patients (7M/6F, median age 62, median KPS 90) with a limited (1–9) number of brain metastases in the primary or recurrent setting were identified. Primary malignancies included colorectal (3), NSCLC (5), RCC (1), breast (1), melanoma (1), uterine (1), and ovarian (1). The median time from initial diagnosis to brain metastases was 20.7 months (range 0–61.3). Treatment was delivered to intact metastases in six patients, to a single resection cavity in six patients, and to both in one patient. A total of 27 lesions were treated. The median number of intact metastases treated was two (range 1–9). Previous treatments included WBRT (5), WBRT + SRS (3), SRS alone (1), and none (4). The most common fractionation schemes were 25 Gy in five fractions and 27.5 Gy in five fractions to each lesion. At a median of 6 months follow up (range 1.26–20.13) after TomoTherapy, 10 patients were deceased, 2 were alive, and 1 was lost to follow up. Systemic progression occurred in seven patients and intracranial progression occurred in five. The median intracranial progression free survival and overall survival after TomoTherapy was 6.3 months. Freedom from local failure for treated lesions was 71% and 59% at 6 and 12 months.Conclusion: TomoTherapy-based hypofractionated radiotherapy to a limited number of metastatic lesions is associated with acceptable intracranial disease control and survival outcomes and represents a viable treatment option in the primary and recurrent setting for select patients.

Is dose escalation achievable for esophageal carcinoma?

AimTo investigate the feasibility of dose escalation using rapid arc (RA) and Helical Tomotherapy (HT) for patients with upper, middle and distal esophageal carcinomas, even for large tumor volumes. BackgroundIn esophageal cancer, for patients with exclusive radio-chemotherapy, local disease control remains poor. Planning study with dose escalation was done for two sophisticated modulated radiotherapy techniques: Rapid arc against Tomotherapy. Materials and methodsSix patients treated with a RA simultaneous integrated boost (SIB) of 60Gy were re-planned for RA and HT techniques with a SIB dose escalated to 70Gy. Dose volume histogram statistics, conformity indices and homogeneity indices were analyzed. For a given set of normal tissue constraints, the capability of each treatment modality to increase the GTV dose to 70Gy was investigated. ResultsEither HT or VMAT may be used to escalate the dose delivered in esophageal tumors while maintaining the spinal cord, lung and heart doses within tolerance. Adequate target coverage was achieved by both techniques. Typically, HT achieved better lung sparing and PTV coverage than did RA. ConclusionsDose escalation for esophageal cancer becomes clinically feasible with the use of RA and HT. This promising result could be explored in a carefully controlled clinical study which considered normal tissue complications and tumor control as endpoints.

Poster — Thur Eve — 15: Improvements in the stability of the tomotherapy imaging beam

Use of helical TomoTherapy based MVCT imaging for adaptive planning requires the image values (HU) to remain stable over the course of treatment. In the past, the image value stability was suboptimal, which required frequent change to the image value to density calibration curve to avoid dose errors on the order of 2–4%. The stability of the image values at our center was recently improved by stabilizing the dose rate of the machine (dose control servo) and performing daily MVCT calibration corrections. In this work, we quantify the stability of the image values over treatment time by comparing patient treatment image density derived using MVCT and KVCT. The analysis includes 1) MVCT ‐ KVCT density difference histogram, 2) MVCT vs KVCT density spectrum, 3) multiple average profile density comparison and 4) density difference in homogeneous locations. Over two months, the imaging beam stability was compromised several times due to a combination of target wobbling, spectral calibration, target change and magnetron issues. The stability of the image values were analyzed over the same period. Results show that the impact on the patient dose calculation is 0.7% +− 0.6%.

High-dose Radiotherapy Using Helical Tomotherapy for Vertebral Metastasis: Early Clinical Outcomes and Cord Dose Specification

For several decades, radiotherapy has been widely used to treat metastatic vertebral tumors. This study was designed to assess the feasibility and early clinical outcomes of high-dose radiotherapy to treat such tumors, using helical tomotherapy. Between June 2009 and December 2011, 51 sites in 36 patients were treated with high-dose radiotherapy using helical tomotherapy for vertebral metastasis. Treatment outcomes and dosimetric analyses of spinal cord were retrospectively evaluated. Median follow-up was 11.5 months (range, 6-34.6) for surviving patients. The median total dose and the number of fractions in the primary helical tomotherapy arm were 2700 cGy and 3 fractions, respectively. Actuarial 6-month local control rates were 85.7%, and symptomatic vertebral compression fractures developed in five patients after a median of 4.2 (range, 2.9-5.7) months. Among 13 patients with 19 metastatic sites who showed pre-treatment impairment in neurologic function, five patients (with seven sites) in whom symptoms were mild showed improvement in neuronal function. The median pre-treatment pain visual analog scale score of 7 decreased to a median of 3 after helical tomotherapy (P < 0.001) at a median of 1 month (range, 0.5-3.2) of follow-up. No significant morbidity developed during follow-up except for one grade 3 esophagitis. The use of helical tomotherapy to treat metastatic vertebral tumors appears to be both safe and reliable in terms of local tumor control and early pain relief. Local progression and the risk of compression fracture in patients with pre-existing spinal instability remain the principal factors of limiting improved clinical and functional outcomes. Optimal dose-fractionation schemes and appropriate patient selection are required to achieve better outcomes with high-dose radiotherapy using helical tomotherapy.

Feasibility of tomotherapy-based image-guided radiotherapy for small cell lung cancer

Background: To assess the tolerance of patients with small cell lung cancer undergoing chemoradiation with tomotherapy-based image-guided radiotherapy (IGRT).Materials and Methods: A retrospective review of the toxicity profile for nine patients with small cell lung cancer of the limited stage who underwent chemoradiation delivered with helical tomotherapy (HT) has been conducted.Results: Acute grade 3–4 hematologic and esophagitis toxicities developed in two and three patients respectively. One patient developed a pulmonary embolism during radiotherapy. Seven patients had weight loss ranging from 0 to 30 pounds (median: 4 pounds). Three patients had treatment breaks ranging from 2 to 12 days. At a median follow-up of 11 months (range: 2–24 months), no patients developed any radiation related toxicities such as grade 3–4 pneumonitis or other long-term complications. The median survival was estimated to be 15 months. There were two local recurrences, three mediastinal recurrences, and six distant metastases.Conclusion: Grade 3–4 toxicities remained significant during chemoradiation when radiation was delivered with tomotherapy-based IGRT. However, the absence of grade 3–4 pneumonitis is promising and the use of HT needs to be investigated in future prospective studies.

Feasibility and Outcome of Helical Tomotherapy for Irradiation in Pediatric Patients with Pineoblastoma

Pineoblastoma is an extremely rare primary tumor occurring in the pineal gland and belongs to the supratentorial primitive neuroectodermal tumors [1,2]. Intensive multimodality treatment that combines surgery, craniospinal irradiation (CSI), and chemotherapy is needed for this uncommon disease. CSI still remains one of the most technically challenging processes in radiation therapy (RT) planning and delivery because of the need to irradiate a very large and complex shaped target volume uniformly. There is a growing concern regarding treatment-related side effects and is the clinical motivation for investigating sophisticated emerging RT techniques to reduce doses to non-target tissues to ameliorate toxicity [3]. Consequently, several strategies have been proposed to limit the radiation-induced toxicity, such as the use of helical tomotherapy (HT) [4,5].

Preliminary Results of the Use of Helical Tomotherapy (HT) in Advanced Nonmelanoma Skin Cancers

To provide an accurate evaluation of efficiency and tolerance (early and late cosmetic results) of HT on different kinds of non-melanoma skin tumors, including basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (CSC), Merkel cell carcinoma (MCC) and adnexal carcinoma (AC).