Total Skin Treatment with Helical Arc Radiotherapy.

For widespread cutaneous lymphoma, such as mycosis fungoides or leukemia cutis, in patients with acute myeloid leukemia (AML) and for chronic myeloproliferative diseases, total skin irradiation is an efficient treatment modality for disease control. Total skin irradiation aims to homogeneously irradiate the skin of the entire body. However, the natural geometric shape and skin folding of the human body pose challenges to treatment. This article introduces treatment techniques and the evolution of total skin irradiation. Articles on total skin irradiation by helical tomotherapy and the advantages of total skin irradiation by helical tomotherapy are reviewed. Differences among each treatment technique and treatment advantages are compared. Adverse treatment effects and clinical care during irradiation and possible dose regimens are mentioned for future prospects of total skin irradiation.

Case report: Stereotactic body radiation therapy with 12 Gy for silencing refractory ventricular tachycardia.

Background: Encouraging results have been reported for the treatment of ventricular tachycardia (VT) with stereotactic body radiation therapy (SBRT) with 25 Gy. SBRT with 12 Gy for refractory VT was designed to reduce long-term cardiac toxicity. Methods: Stereotactic body radiation therapy-VT simulation, planning, and treatment were performed using standard techniques. A patient was treated with a marginal dose of 12 Gy in a single fraction to the planning target volume (PTV). The goal was for at least ≥ 95% of the PTV to be covered by at least 95% of 12 Gy radiation. Results: From April 2021 through June 2022, a patient with refractory VT underwent treatment. The volume for PTV was 65.8 cm3. The mean radiation dose administered to the heart (the heart volume excluding the PTV) was 2.2 Gy. No acute or late toxicity was observed after SBRT. Six months after SBRT, the patient experienced new monomorphic right ventricular outflow tract (RVOT) VT. Interestingly, the substrate of the left ventricular basal to middle posteroseptal wall before SBRT was turned into scar zones with a local voltage < 0.5 mV. Catheter ablation to treat RVOT VT was performed, and the situation remains stable to date. Conclusion: This study reports the first patient with refractory VT successfully treated with 12.0 Gy SBRT, suggesting that 12 Gy is a potential dose to treat refractory VT. Further investigations and enrollment of more patients are warranted to assess the long-term efficacy and side effects of this treatment.

Integrating 18 F-FDG PET/CT with lung dose-volume for assessing lung inflammatory changes after arc-based radiotherapy for esophageal cancer: A pilot study.

OBJECTIVE: The incidence of radiation pneumonitis (RP) has a highly linear relationship with low-dose lung volume. We previously established a volume-based algorithm (VBA) method to improve low-dose lung volume in radiotherapy (RT). This study assessed lung inflammatory changes by integrating fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) with VBA for esophageal cancer patients undergoing arc-based RT. METHODS: Thirty esophageal cancer patients received 18 F-FDG PET/CT imaging pre-RT and post-RT were included in a retrospective pilot study. We fused lung doses and parameters of PET/CT in RT planning. Based on VBA, we used the 5Gy isodose curve to define high-dose (HD) and low-dose (LD) regions in the lung volume. We divided patients into non-RP (nRP) and RP groups. The maximum, mean standardized uptake value (SUVmax, SUVmean), global lung glycolysis (GLG), mean lung dose (MLD) and V5-30 in lungs were analyzed. Area under the curve values were utilized to identify optimal cut-off values for RP. RESULTS: Eleven patients in the nRP group and 19 patients in the RP group were identified. In 30 RP lungs, post-RT SUVmax, SUVmean and GLG of HD regions showed significant increases compared to values for pre-RT lungs. There were no significant differences in values of 22 nRP lungs. Post-RT SUVmax and SUVmean of HD regions, MLD, and lung V5 and V10 in RP lungs were significantly higher than in nRP lungs. For detecting RP, the optimal cut-off values were post-RT SUVmax > 2.28 and lung V5  > 47.14%. CONCLUSION: This study successfully integrated 18 F-FDG PET/CT with VBA to assess RP in esophageal cancer patients undergoing RT. Post-RT SUVmax > 2.28 and lung V5  > 47.14% might be potential indicators of RP.

Cardiac Function after Modern Radiation Therapy with Volumetric Modulated Arc Therapy or Helical Tomotherapy for Advanced Left-Breast Cancer Receiving Regional Nodal Irradiation.

BACKGROUND: Protecting cardiac function in patients with advanced left-breast cancer receiving radiation therapy (RT) with regional nodal irradiation (RNI) is an important issue. Modern RT techniques can limit cardiac exposure. The aim of this study was to explore the association be-tween cardiac dose and cardiac function. METHODS: Between 2017 and 2020, we retrospectively reviewed left-breast cancer patients who received adjuvant RT, including RNI with either volumetric-modulated arc therapy (VMAT) or helical tomotherapy (HT). Left ventricular ejection fraction (LVEF) was assessed by echocardiography before RT and 1 year after RT to detect any early deterioration in cardiac systolic function. RESULTS: A total of 30 eligible patients were enrolled. The median follow-up time from the initiation of RT was 3.9 years (range 0.6-5 years). Seventeen patients received VMAT, and the other 13 patients received HT. The median RT dose was 55 Gray (Gy), and the mean heart dose was 3.73 Gy (range 1.95-9.36 Gy). The median LVEF before and after RT was 68% and 68.5%, respectively. No obvious deterioration was found. There was no association between cardiac dose (mean heart dose, V5-V30) and LVEF (change in values or post-RT). CONCLUSIONS: For left-breast cancer patients undergoing RT with RNI, VMAT, or HT can be used to limit cardiac exposure. Cardiac function as evaluated by LVEF revealed no obvious deterioration after RT in our patients, and no association was found between cardiac dose and LVEF in those treated with either VMAT or HT in early cardiac surveillance.

Planning evaluation of a novel volume-based algorithm for personalized optimization of lung dose in VMAT for esophageal cancer.

Radiotherapy treatment planning (RTP) is time-consuming and labor-intensive since medical physicists must devise treatment plans carefully to reduce damage to tissues and organs for patients. Previously, we proposed the volume-based algorithm (VBA) method, providing optimal partial arcs (OPA) angle to achieve the low-dose volume of lungs in dynamic arc radiotherapy. This study aimed to implement the VBA for esophageal cancer (EC) patients and compare the lung dose and delivery time between full arcs (FA) without using VBA and OPA angle using VBA in volumetric modulated arc therapy (VMAT) plans. We retrospectively included 30 patients diagnosed with EC. RTP of each patient was replanned to 4 VMAT plans, including FA plans without (FA-C) and with (FA + C) dose constraints of OARs and OPA plans without (OPA-C) and with (OPA + C) dose constraints of OARs. The prescribed dose was 45 Gy. The OARs included the lungs, heart, and spinal cord. The dose distribution, dose-volume histogram, monitor units (MUs), delivery time, and gamma passing rates were analyzed. The results showed that the lung V5 and V10 in OPA + C plans were significantly lower than in FA + C plans (p < 0.05). No significant differences were noted in planning target volume (PTV) coverage, lung V15, lung V20, mean lung dose, heart V30, heart V40, mean heart dose, and maximal spinal cord dose between FA + C and OPA + C plans. The delivery time was significantly longer in FA + C plans than in OPA + C plans (237 vs. 192 s, p < 0.05). There were no significant differences between FA + C and OPA + C plans in gamma passing rates. We successfully applied the OPA angle based on the VBA to clinical EC patients and simplified the arc angle selection in RTP. The VBA could provide a personalized OPA angle for each patient and effectively reduce lung V5, V10, and delivery time in VMAT.

Modern Rotational Radiation Techniques with Volumetric Modulated Arc Therapy or Helical Tomotherapy for Optimal Sparing of the Lung and Heart in Left-Breast Cancer Radiotherapy Plus Regional Nodal Irradiation: A Comparative Dosimetric Analysis.

BACKGROUND: For advanced breast cancer with lymph node involvement, adjuvant radiotherapy (RT) with regional nodal irradiation (RNI) has been indicated to reduce cancer recurrence and mortality. However, an extensive RT volume is associated with normal organ exposure, which increases the toxicity and affects patient outcomes. Modern arc RT techniques can improve normal organ sparing compared with conventional techniques. The aim of this study was to explore the optimal technique for left-breast RT with RNI. METHODS: We retrospectively reviewed patients receiving RT with RNI for left-breast cancer. We used modern arc RT techniques with either volumetric-modulated arc therapy (VMAT) or helical tomotherapy (HT) with a novel block technique, and compared differences in dosimetry parameters between the two groups. Subgroup analysis of RNI with or without internal mammary node (IMN) volume was also performed. RESULTS: A total of 108 eligible patients were enrolled between 2017 and 2020, of whom 70 received VMAT and 38 received HT. The median RT dose was 55 Gy. No significant differences were found regarding the surgery, RT dose, number of fractions, target volume, and RNI volume between the VMAT and HT groups. VMAT reduced the heart mean dose more than HT (3.82 vs. 5.13 Gy, p < 0.001), as well as the cardiac parameters of V5-V20, whole-lung mean dose, lung parameters of V5-V20, and contralateral-breast and esophagus mean dose. In the subgroup analysis of RNI with IMNs, the advantage of VMAT persisted in protecting the heart, lung, contralateral breast, and esophagus. HT was beneficial for lowering the thyroid mean dose. For RNI without IMN, VMAT improved the low-dose exposure of the heart and lung, but HT was similar to VMAT in terms of heart, whole-lung, and contralateral-breast mean dose. CONCLUSIONS: For patients with left-breast cancer receiving adjuvant RT with RNI, VMAT reduced the exposure dose to the heart, lung, contralateral breast, and esophagus compared with HT. VMAT was superior to HT in terms of normal organ sparing in the patients who underwent RNI with IMN irradiation. Considering the reduction in normal organ exposure and potential toxicity, VMAT is the optimal technique for patients receiving RNI when deep inspiration breath-hold is not available.

Volume-based algorithm of lung dose optimization in novel dynamic arc radiotherapy for esophageal cancer.

This study aims to develop a volume-based algorithm (VBA) that can rapidly optimize rotating gantry arc angles and predict the lung V5 preceding the treatment planning. This phantom study was performed in the dynamic arc therapy planning systems for an esophageal cancer model. The angle of rotation of the gantry around the isocenter as defined as arc angle (θA), ranging from 360° to 80° with an interval of 20°, resulting in 15 different θA of treatment plans. The corresponding predicted lung V5 was calculated by the VBA, the mean lung dose, lung V5, lung V20, mean heart dose, heart V30, the spinal cord maximum dose and conformity index were assessed from dose-volume histogram in the treatment plan. Correlations between the predicted lung V5 and the dosimetric indices were evaluated using Pearson's correlation coefficient. The results showed that the predicted lung V5 and the lung V5 in the treatment plan were positively correlated (r = 0.996, p < 0.001). As the θA decreased, lung V5, lung V20, and the mean lung dose decreased while the mean heart dose, V30 and the spinal cord maximum dose increased. The V20 and the mean lung dose also showed high correlations with the predicted lung V5 (r = 0.974, 0.999, p < 0.001). This study successfully developed an efficient VBA to rapidly calculate the θA to predict the lung V5 and reduce the lung dose, with potentials to improve the current clinical practice of dynamic arc radiotherapy.

Cone-beam CT image quality improvement using Cycle-Deblur consistent adversarial networks (Cycle-Deblur GAN) for chest CT imaging in breast cancer patients.

Cone-beam computed tomography (CBCT) integrated with a linear accelerator is widely used to increase the accuracy of radiotherapy and plays an important role in image-guided radiotherapy (IGRT). For comparison with fan-beam computed tomography (FBCT), the image quality of CBCT is indistinct due to X-ray scattering, noise, and artefacts. We proposed a deep learning model, "Cycle-Deblur GAN", combined with CycleGAN and Deblur-GAN models to improve the image quality of chest CBCT images. The 8706 CBCT and FBCT image pairs were used for training, and 1150 image pairs were used for testing in deep learning. The generated CBCT images from the Cycle-Deblur GAN model demonstrated closer CT values to FBCT in the lung, breast, mediastinum, and sternum compared to the CycleGAN and RED-CNN models. The quantitative evaluations of MAE, PSNR, and SSIM for CBCT generated from the Cycle-Deblur GAN model demonstrated better results than the CycleGAN and RED-CNN models. The Cycle-Deblur GAN model improved image quality and CT-value accuracy and preserved structural details for chest CBCT images.

Tomotherapy as an Alternative Irradiative Treatment for Complicated Keloids.

The aim of this study was to investigate the treatment of complicated keloids with helical tomotherapy (HT) and electron beam radiotherapy. From July 2018 to September 2018, 11 patients with 23 keloid lesions treated with HT were enrolled. Additionally, 11 patients with 20 lesions treated with electron beam radiotherapy in the same period were enrolled. Patients in both groups were treated within 24 h after surgical excision of the keloid lesion with 13.5 Gy in three consecutive daily fractions. The median follow-up period was 15 months. The local control rate was 91.3% and 80% in the HT group and the electron beam group, respectively. No acute adverse effects were observed in either group, but most patients exhibited pigmentation. No radiation-induced cancer occurred in these patients up to the time of this report. Pain and pruritus improved for all patients and more obviously for three patients with complicated keloids treated with HT. The measured surface dose was 103.7-112.5% and 92.8-97.6% of the prescribed dose in the HT group and the electron beam group, respectively. HT can be considered an alternative in cases where it is not feasible to use multiple electron fields, due to encouraging clinical outcomes.

Helical tomotherapy with a complete-directional-complete block technique effectively reduces cardiac and lung dose for left-sided breast cancer.

OBJECTIVES: To evaluate the feasibility and optimal restricted angle of the complete-directional-complete block (CDCB) technique in helical tomotherapy (HT) by including regional nodal irradiation (RNI) with the internal mammary node (IMN) in left-sided breast cancer. METHODS: Ten left-sided breast cancer patients treated with 50 Gy in 25 fractions were compared with five-field intensity-modulated radiation therapy (5F-IMRT) and six types of HT plans. In the HT plans, complete block (CB), organ-based directional block (OBDB) and CDCB with different restricted angles were used. RESULTS: The conformity index (CI) between the CDCB0,10,15,20 and 5F-IMRT groups was similar. Compared to CB, OBDB and 5F-IMRT, CDCB20 resulted in a decreased ipsilateral mean lung dose. The low-dose region (V5) of the ipsilateral lung in OBDB (84.0%) was the highest among all techniques (p < 0.001). The mean dose of the heart in CB was significantly reduced (by 11.5-22.4%) compared with other techniques. The V30 of the heart in CDCB20 (1.9%) was significantly lower than that of CB, OBDB and 5F-IMRT. Compared to the mean dose of the left anterior descending (LAD) artery of 5F-IMRT (27.0 Gy), CDCB0, CDCB10, CDCB15, CDCB20 and OBDB reduced the mean dose effectively by 31.7%, 38.3%, 39.6%, 42.0 and 56.2%, respectively. Considering the parameters of the organs-at-risk (OARs), CDCB10,15,20 had higher expectative values than the other techniques (p = 0.01). CONCLUSIONS: HT with the CDCB technique is feasible for treating left-sided breast cancer patients. The CDCB10-20 techniques not only achieved similar planning target volume coverage, homogeneity and dose conformity but also allowed better sparing of the heart and bilateral lungs. ADVANCES IN KNOWLEDGE: For left-sided breast cancer patients whose RNI field includes the IMN, heart avoidance is an important issue. The CDCB technique achieved good PTV coverage, homogeneity and dose conformity and allowed better sparing of the mean dose of the lung, the LAD artery, and the heart and reduced the V30 of the heart.

Simultaneous integrated boost with helical arc radiotherapy of total skin (HEARTS) to treat cutaneous manifestations of advanced, therapy-refractory cutaneous lymphoma and leukemia - dosimetry comparison of different regimens and clinical application.

BACKGROUND: Helical irradiation of the total skin (HITS) was modified as simultaneous integrated boost (SIB)-helical arc radiotherapy of total skin (HEARTS) technique and applied to an acute myeloid leukemia (AML) patient with disseminated leukemia cutis. METHODS: The original HITS plan was revised for different regimens, i.e. HEARTS, low-dose HEARTS and SIB-HEARTS. The uniformity index (UI), conformity index (CI), and dose of organs at risk (OARs) were used to evaluate the plans. Additionally, the SIB-HEART (21/15 Gy) was delivered to the total skin and chloromas. RESULTS: No significant differences were observed for the CI and UI between HITS and HEARTS regimens. Compared with HITS, the reduced mean doses to various bone marrows ranged from 17 to 88%. The mean OARs doses for the head, chest and abdomen of a patient with AML treated with SIB-HEARTS (21/15 Gy) were 2.1 to 21.9 Gy, 1.8 to 7.8 Gy and 1.7 to 3.3 Gy, respectively. No severe adverse effects were noted except for grade 4 leukocytopenia and thrombocytopenia. CONCLUSION: HEARTS and different regimens reduced the dose to OARs and bone marrow while maintaining the uniformity and conformity. SIB-HEARTS deliveries different doses to the total skin and enlarged tumors simultaneously. TRIAL REGISTRATION: Retrospectively registered and approved by the Institutional Review Board of our hospital ( FEMH-106151-C ).

Impact of postoperative daily image-guided intensity-modulated radiotherapy on overall and local progression-free survival in patients with oral cavity cancer.

BACKGROUND: We compared the outcome of patients who received non-image-guided intensity-modulated radiotherapy (IMRT) with those who received helical tomotherapy (HT), a daily image-guided radiotherapy (IGRT), after surgery for oral cavity cancer (OCC). METHODS: During the period November 2006 to December 2013, a total of 152 postoperative OCC patients underwent either IMRT (n = 79) or daily IGRT (n = 73) 4 to 6 weeks after surgery. Patients in the IMRT group received 6 MV photon beams to 7 fields and those in the IGRT group received daily fractions of 1.8 or 2 Gy on five consecutive days. RESULTS: Patients who received daily IGRT had higher 5-year overall survival than those who received IMRT (87% versus 48%, p = 0.015). The local progression-free survival rate was also higher in patients who received IGRT (85% versus 58%, p = 0.006). More patients in the IGRT group completed the package of overall treatment time in ≤ 13 weeks and completed their course of radiation therapy in ≤ 8 weeks than patients in the IMRT group (89% versus 68%, p = 0.002; 84% versus 58%, p = 0.001), respectively. The rate of local failure in the primary tumor area was 24.0 % in the IMRT group and 6.8% in the IGRT group. Among patients with primary local failure, the marginal failure rate was 52.6% in the IMRT group and 0 % in the IGRT group. CONCLUSIONS: For patients with locally advanced OCC, postoperative IGRT results in better overall survival, better local progression-free survival, less marginal failure and shorter overall treatment time than postoperative non-image-guided IMRT.

Fan-shaped complete block on helical tomotherapy for esophageal cancer: a phantom study.

Radiation pneumonitis (RP) is a common complication for radiotherapy of esophageal cancer and is associated with the low dose irradiated lung volume. This study aims to reduce the mean lung dose (MLD) and the relative lung volume at 20 Gy (V 20) and at low dose region using various designs of the fan-shaped complete block (FSCB) in helical tomotherapy. Hypothetical esophageal tumor was delineated on an anthropomorphic phantom. The FSCB was defined as the fan-shaped radiation restricted area located in both lungs. Seven treatment plans were performed with nonblock design and FSCB with different fan angles, that is, from 90° to 140°, with increment of 10°. The homogeneous index, conformation number, MLD, and the relative lung volume receiving more than 5, 10, 15, and 20 Gy (V 5, V 10, V 15, and V 20) were determined for each treatment scheme. There was a substantial reduction in the MLD, V 5, V 10, V 15, and V 20 when using different types of FSCB as compared to the nonblock design. The reduction of V 20, V 15, V 10, and V 5 was 6.3%-8.6%, 16%-23%, 42%-57%, and 42%-66% for FSCB 90°-140°, respectively. The use of FSCB in helical tomotherapy is a promising method to reduce the MLD, V 20, and relative lung volume in low dose region, especially in V 5 and V 10 for esophageal cancer.

Left-sided whole breast irradiation with hybrid-IMRT and helical tomotherapy dosimetric comparison.

PURPOSE: Limited-tomotherapy and hybrid-IMRT treatment techniques were compared for reductions in ipsilateral and contralateral lung, heart, and contralateral breast radiation doses. METHODS AND MATERIALS: Thirty consecutively treated left-sided early-stage breast cancer patients were scheduled for lTomo and hIMRT. For the hIMRT plan conventional tangential-field and four-field IMRT plans were combined with different weightings in the prescribed dose. For the lTomo plan a geometrically limited arc was designed for the beamlet entrance. A D p of 50.4 Gy in 28 fractions was used for the PTV. The dose coverage, homogeneity index, conformity index of the target, and the dose volumes of critical structures were compared. RESULTS: Both modalities presented similar target coverage. The homogeneity and conformity were improved for lTomo with P < 0.001 and P = 0.006, respectively. In the lTomo plan a concave dose distribution was generated with significant dose reductions in both high and low dose regions for ipsilateral lung and heart (P < 0.001). Conclusions. lTomo plan can have similar dose coverage and better homogeneity and conformity to the target. By properly designing the directionally and completely blocked structure, lTomo plan was developed successfully in reducing doses to the healthy tissues for early-stage left-sided breast cancer radiotherapy.

Clinical effectiveness, toxicity, and failure patterns of helical tomotherapy for postoperative oral cavity cancer patients.

BACKGROUND: The outcome of postoperative high- and intermediate-risk oral cavity cancer (OCC) patients receiving helical tomotherapy (HT) remains limited. MATERIALS AND METHODS: Between November 2006 and November 2012, 53 postoperative high- and intermediate-risk OCC patients treated with HT were enrolled. RESULTS: The 4-year locoregional, local, and regional control rates were 66%, 76.4%, and 94.3%, respectively. The 4-year locoregional control rates of oral tongue and buccal mucosa cancer were 88.3% and 37.1%, respectively (P=0.012). Eleven (20.8%) patients experienced locoregional failure. In-field failure occurred in six of 53 (11.3%) in the primary area and three of 53 (5.7%) in the regional lymph-node area. No marginal failure was noted. Two of 53 (3.8%) experienced out-of-field failure. The rates of grade 3 dermatitis, mucositis, and dysphagia were 11%, 34%, and 13%, respectively. No grade 3 xerostomia was noted. Grade 2 xerostomia was 33% at month 6 and declined to 0 at month 48. A rate of 56% of grade 2 trismus at month 6 was noted, and declined to around 30% after 2 years. No grade 3 trismus was noted after 2 years. CONCLUSION: HT as a postoperative modality provided satisfying results, especially for xerostomia and trismus, and was impressive in high- and intermediate-risk OCC patients receiving postoperative HT.

Predicting the severity and prognosis of trismus after intensity-modulated radiation therapy for oral cancer patients by magnetic resonance imaging.

To develop magnetic resonance imaging (MRI) indicators to predict trismus outcome for post-operative oral cavity cancer patients who received adjuvant intensity-modulated radiation therapy (IMRT), 22 patients with oral cancer treated with IMRT were studied over a two-year period. Signal abnormality scores (SA scores) were computed from Likert-type ratings of the abnormalities of nine masticator structures and compared with the Mann-Whitney U-test and Kruskal-Wallis one-way ANOVA test between groups. Seventeen patients (77.3%) experienced different degrees of trismus during the two-year follow-up period. The SA score correlated with the trismus grade (r = 0.52, p<0.005). Patients having progressive trismus had higher mean doses of radiation to multiple structures, including the masticator and lateral pterygoid muscles, and the parotid gland (p<0.05). In addition, this group also had higher SA-masticator muscle dose product at 6 months and SA scores at 12 months (p<0.05). At the optimum cut-off points of 0.38 for the propensity score, the sensitivity was 100% and the specificity was 93% for predicting the prognosis of the trismus patients. The SA score, as determined using MRI, can reflect the radiation injury and correlate to trismus severity. Together with the radiation dose, it could serve as a useful biomarker to predict the outcome and guide the management of trismus following radiation therapy.

Helical irradiation of the total skin with dose painting to replace total skin electron beam therapy for therapy-refractory cutaneous CD4+ T-cell lymphoma.

A 36-year-old woman was diagnosed with a therapy-refractory cutaneous CD4+ T-cell lymphoma, T3N0M0B0, and stage IIB. Helical irradiation of the total skin (HITS) and dose painting techniques, with 30 Gy in 40 fractions interrupted at 20 fractions with one week resting, 4 times per week were prescribed. The diving suit was dressed whole body to increase the superficial dose and using central core complete block (CCCB) technique for reducing the internal organ dose. The mean doses of critical organs of head, chest, and abdomen were 2.1 to 29.9 Gy, 2.9 to 8.1 Gy, and 3.6 to 15.7 Gy, respectively. The mean dose of lesions was 84.0 cGy. The dosage of left side pretreated area was decreased 57%. The tumor regressed progressively without further noduloplaques. During the HITS procedure, most toxicity was grade I except leukocytopenia with grade 3. No epitheliolysis, phlyctenules, tumor lysis syndrome, fever, vomiting, dyspnea, edema of the extremities, or diarrhea occurred during the treatment. HITS with dose painting techniques provides precise dosage delivery with impressive results, sparing critical organs, and offering limited transient and chronic sequelae for previously locally irradiated, therapy-refractory cutaneous T-cell lymphoma.

Total marrow irradiation as part of autologous stem cell transplantation for Asian patients with multiple myeloma.

To compare the outcomes of melphalan 200 mg/m² (HDM200) and 8 Gy total marrow irradiation (TMI) delivered by helical tomotherapy plus melphalan 140 mg/m² (HDM140 + TMI 8 Gy) in newly diagnosed symptomatic multiple myeloma (MM) Asian patients. Between 2007 and 2010, nine consecutive myeloma patients who were scheduled to undergo autologous stem cell transplantation (ASCT) were studied. The patients received three cycles of vincristine-adriamycin-dexamethasone (VAD) regimen as induction chemotherapy, and if they had a partial response, peripheral blood stem cells were collected by dexamethasone-etoposide-cyclophosphamide-cisplatin (DECP). In arm A, six patients received the HDM200. In arm B, three patients received HDM140 + TMI 8 Gy. In arm B, the neutropenic duration was slightly longer than in arm A (P = 0.048). However, hematologic recovery (except for neutrophils), transfusion requirement, median duration of hospitalization, and the dose of G-CSF were similar in both arms. The median duration of overall survival and event-free survival was similar in the two arms (P = 0.387). As a conditioning regiment, HDM140 + TMI 8 Gy provide another chance for MM Asian patients who were not feasible for HDM200.

Head and neck irradiation modulates pharmacokinetics of 5-fluorouracil and cisplatin.

BACKGROUND: 5-fluorouracil (5-FU) and cisplatin (CDDP) are used to enhance radiotherapy (RT) effect for head and neck (HN) cancers. However, the effect of local RT on systemic chemotherapeutics remains unclear. Here, we evaluated the influence of HN irradiation on the pharmacokinetics (PK) of 5-FU and CDDP in rats as experimental model. METHODS: The radiation dose distributions of HN cancer patients were determined for the low dose areas, which are generously deposited around the target volume. Two Gy and 0.5 Gy RT were selected. Single-fraction radiation was delivered to the HN of Sprague-Dawley rats. 5-FU at 100 mg/kg or CDDP at 5 mg/kg was intravenously infused 24 hours after radiation. RESULTS: Radiation at 2 Gy reduced the area under the plasma concentration vs. time curve (AUC) of 5-FU and CDDP by 16% and 29% compared to non-irradiated controls, respectively. This was accompanied by incremental total plasma clearance values. Intriguingly, low dose radiation at 0.5 Gy resulted in a similar pharmacokinetic profile, with a 17% and 33% reduction in the AUC of 5-FU and CDDP, respectively. The changes in AUC of bile, which increases with RT, were opposite to AUC of plasma for both drugs. CONCLUSIONS: The local HN RT could modulate systemic PK of 5-FU and CDDP in rats. This unexpected RT-PK phenomena may provide a reference for adjustment of drug administration and is worthy of further investigation. TRIAL REGISTRATION: ClinicalTrials.gov ID NCT01755585 and NCT01609114.

An attempted substitute study of total skin electron therapy technique by using helical photon tomotherapy with helical irradiation of the total skin treatment: a phantom result.

An anthropomorphic phantom was used to investigate a treatment technique and analyze the dose distributions for helical irradiation of the total skin (HITS) by helical tomotherapy (HT). Hypothetical bolus of thicknesses of 0, 10, and 15 mm was added around the phantom body to account for the dose homogeneity and setup uncertainty. A central core structure was assigned as a "complete block" to force the dose tangential delivery. HITS technique with prescribed dose (D p ) of 36 Gy in 36 fractions was generated. The radiochromic EBT2 films were used for the dose measurements. The target region with 95.0% of the D p received by more than 95% of the PTV was obtained. The calculated mean doses for the organs at risk (OARs) were 4.69, 3.10, 3.20, and 2.94 Gy for the lung, heart, liver, and kidneys, respectively. The measurement doses on a phantom surface for a plan with 10 mm hypothetical bolus and bolus thicknesses of 0, 1, 2, and 3 mm are 89.5%, 111.4%, 116.9%, and 117.7% of D p , respectively. HITS can provide an accurate and uniform treatment dose in the skin with limited doses to OARs and is safe to replace a total skin electron beam regimen.