Vitamin D deficiency and graft-versus-host disease in hematopoietic stem cell transplant population.

Vitamins are the organic compounds that have long been known to play a significant role in our body by functioning as hormones and antioxidants. Vitamin D, a fat-soluble vitamin, is the main regulator of calcium hemostasis in our body. At the same time, it is also known to show its potential effects on the immune system by modulating the differentiation, activation, and proliferation of T and B lymphocytes. The immunomodulatory properties of vitamin D are also known to have a crucial role in the prevention and treatment of graft-versus-host disease. Patients undergoing hematopoietic stem cell transplantation are particularly at risk of vitamin D deficiency. This review article expands our understanding of vitamin D, its immunomodulatory effects, and its role in prevention and treatment of graft-versus-host disease.

Multi-Institutional Experience of Stereotactic Ablative Radiation Therapy for Stage I Small Cell Lung Cancer.

PURPOSE: For inoperable stage I (T1-T2N0) small cell lung cancer (SCLC), national guidelines recommend chemotherapy with or without conventionally fractionated radiation therapy. The present multi-institutional cohort study investigated the role of stereotactic ablative radiation therapy (SABR) for this population. METHODS AND MATERIALS: The clinical and treatment characteristics, toxicities, outcomes, and patterns of failure were assessed in patients with histologically confirmed stage T1-T2N0M0 SCLC. Kaplan-Meier analysis was used to evaluate the survival outcomes. Univariate and multivariate analyses identified predictors of outcomes. RESULTS: From 24 institutions, 76 lesions were treated in 74 patients (median follow-up 18 months). The median age and tumor size was 72 years and 2.5 cm, respectively. Chemotherapy and prophylactic cranial irradiation were delivered in 56% and 23% of cases, respectively. The median SABR dose and fractionation was 50 Gy and 5 fractions. The 1- and 3-year local control rate was 97.4% and 96.1%, respectively. The median disease-free survival (DFS) duration was 49.7 months. The DFS rate was 58.3% and 53.2% at 1 and 3 years, respectively. The median, 1-year, and 3-year disease-specific survival was 52.3 months, 84.5%, and 64.4%, respectively. The median, 1-year, and 3-year overall survival (OS) was 17.8 months, 69.9%, and 34.0% respectively. Patients receiving chemotherapy experienced an increased median DFS (61.3 vs 9.0 months; P=.02) and OS (31.4 vs 14.3 months; P=.02). The receipt of chemotherapy independently predicted better outcomes for DFS/OS on multivariate analysis (P=.01). Toxicities were uncommon; 5.2% experienced grade ≥2 pneumonitis. Post-treatment failure was most commonly distant (45.8% of recurrence), followed by nodal (25.0%) and "elsewhere lung" (20.8%). The median time to each was 5 to 7 months. CONCLUSIONS: From the findings of the largest report of SABR for stage T1-T2N0 SCLC to date, SABR (≥50 Gy) with chemotherapy should be considered a standard option.

The KRAS-Variant and Cetuximab Response in Head and Neck Squamous Cell Cancer: A Secondary Analysis of a Randomized Clinical Trial.

IMPORTANCE: There is a significant need to find biomarkers of response to radiotherapy and cetuximab in locally advanced head and neck squamous cell carcinoma (HNSCC) and biomarkers that predict altered immunity, thereby enabling personalized treatment. OBJECTIVES: To examine whether the Kirsten rat sarcoma viral oncogene homolog (KRAS)-variant, a germline mutation in a microRNA-binding site in KRAS, is a predictive biomarker of cetuximab response and altered immunity in the setting of radiotherapy and cisplatin treatment and to evaluate the interaction of the KRAS-variant with p16 status and blood-based transforming growth factor ß1 (TGF-ß1). DESIGN, SETTING, AND PARTICIPANTS: A total of 891 patients with advanced HNSCC from a phase 3 trial of cisplatin plus radiotherapy with or without cetuximab (NRG Oncology RTOG 0522) were included in this study, and 413 patients with available samples were genotyped for the KRAS-variant. Genomic DNA was tested for the KRAS-variant in a CLIA-certified laboratory. Correlation of the KRAS-variant, p16 positivity, outcome, and TGF-ß1 levels was evaluated. Hazard ratios (HRs) were estimated with the Cox proportional hazards model. MAIN OUTCOMES AND MEASURES: The correlation of KRAS-variant status with cetuximab response and outcome, p16 status, and plasma TGF-ß1 levels was tested. RESULTS: Of 891 patients eligible for protocol analyses (786 male [88.2%], 105 [11.2%] female, 810 white [90.9%], 81 nonwhite [9.1%]), 413 had biological samples for KRAS-variant testing, and 376 had plasma samples for TGF-ß1 measurement. Seventy patients (16.9%) had the KRAS-variant. Overall, for patients with the KRAS-variant, cetuximab improved both progression-free survival (PFS) for the first year (HR, 0.31; 95% CI, 0.10-0.94; P = .04) and overall survival (OS) in years 1 to 2 (HR, 0.19; 95% CI, 0.04-0.86; P = .03). There was a significant interaction of the KRAS-variant with p16 status for PFS in patients treated without cetuximab. The p16-positive patients with the KRAS-variant treated without cetuximab had worse PFS than patients without the KRAS-variant (HR, 2.59; 95% CI, 0.91-7.33; P = .07). There was a significant 3-way interaction among the KRAS-variant, p16 status, and treatment for OS (HR, for KRAS-variant, cetuximab and p16 positive, 0.22; 95% CI, 0.03-1.66; HR for KRAS-variant, cetuximab and p16 negative, 1.43; 95% CI, 0.48-4.26; HR for KRAS-variant, no cetuximab and p16 positive, 2.48; 95% CI, 0.64-9.65; and HR for KRAS-variant, no cetuximab and p16 negative, 0.61; 95% CI, 0.23-1.59; P = .02). Patients with the KRAS-variant had significantly elevated TGF-ß1 plasma levels (median, 23 376.49 vs 18 476.52 pg/mL; P = .03) and worse treatment-related toxic effects. CONCLUSIONS AND RELEVANCE: Patients with the KRAS-variant with HNSCC significantly benefit from the addition of cetuximab to radiotherapy and cisplatin, and there is a significant interaction between the KRAS-variant and p16 status. Elevated TGF-ß1 levels in patients with the KRAS-variant suggests that cetuximab may help these patients by overcoming TGF-ß1-induced suppression of antitumor immunity. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00265941.

Quality of Life and Performance Status From a Substudy Conducted Within a Prospective Phase 3 Randomized Trial of Concurrent Accelerated Radiation Plus Cisplatin With or Without Cetuximab for Locally Advanced Head and Neck Carcinoma: NRG Oncology Radiation Therapy Oncology Group 0522.

PURPOSE: To analyze the quality of life (QOL) and performance status (PS) (secondary outcome) in patients with stage III to IV head and neck cancer (HNC) enrolled on a prospective randomized phase 3 trial comparing radiation-cisplatin without cetuximab (CIS) or with cetuximab (CET/CIS). The QOL hypothesis proposed a between-arm difference in Functional Assessment of Cancer Therapy-Head and Neck (FACT-HN) total score of ≥10% of the instrument range from baseline to 1 year. METHODS AND MATERIALS: Patients who gave consent to the QOL/PS study completed the FACT-HN, Performance Status Scale for HNC (PSS-HN), and EuroQol (EQ-5D) at baseline through to 5 years. The pretreatment QOL/PS scores were correlated with outcome and p16 status in patients with oropharyngeal cancer (OPC). RESULTS: Of 818 analyzable patients, the 1-year change from baseline score for FACT-HN total was -0.41 (CIS arm) and -5.11 (CET/CIS arm) (P=.016), representing a 3.2% between-arm change of the FACT-HN total score. The mean EQ-5D index and PSS-HN scores were not significantly different between arms. The p16-positive OPC patients had significantly higher baseline and 1-year scores for PSS-HN, FACT-HN total, physical and functional subscales, and 2-years for the EQ-5D index compared with p16-negative OPC patients. Higher pretreatment PSS-HN diet, PSS-HN eating, FACT-HN, and EQ-5D index scores were associated with better overall survival (OS) and progression-free (PFS) survival on multivariate analysis. Higher baseline FACT-HN total, functional, physical subscale, and EQ-5D index scores were associated with improved OS and PFS in p16-positive OPC patients but not in p16-negative and non-OPC patients. CONCLUSION: There was no clinically meaningful difference in QOL/PS between arms. The p16-positive OPC patients had significantly higher QOL/PS than did p16-negative patients. Pretreatment QOL/PS is a significant independent predictor of outcome in locally advanced HNC.

Changes in Non-Small Cell Lung Cancer Tumor Location Secondary to Gastric Distension, Implications in the Context of Stereotactic Body Radiation Therapy.

OBJECTIVE: Stereotactic body radiation therapy (SBRT) facilitates highly conformal dose distributions to a targe tumor volume. Accurate tumor localization is extremely important, and lung tumors pose a unique challenge due to respiratory motion. Patients are required to fast before PET/CT but not before CT simulation and daily treatment, introducing potential variability from gastric distension. METHODS: A case was reviewed involving a patient with early-stage NSCLC which was simulated and treated with SBRT. PET/CT performed while fasting showed an isolated left lower lobe lesion. Following CT simulation, CT and PET/CT images were superimposed for comparison and treatment planning. RESULTS: Tumor location variation was apparent following image superimposition. Simulation CT showed significant gastric distension compared to PET/CT. The patient was resimulated while fasting, resulting in accurate and reproducible tumor localization for treatment planning. CONCLUSIONS: Gastric distension can alter tumor location and treatment volumes for radiotherapy planning, possibly resulting in inaccurate treatment administration.

Late Effects of Radiation Therapy in Pediatric Cancer Survivors.

The overall survival rates of many pediatric cancers continue to improve with each decade due to new advances in therapy. As this trend continues, the focus and importance of minimizing acute and long-term toxicity associated with treatment is paramount. While significant research regarding many of the late responses of normal tissues associated with radiation exposure has been established, future endeavors must be directed toward the identification of therapy related factors including radiation total dose, dose rate, exposure, and target treatment volumes. Awareness of short and long-term health risks of these patients is important and careful follow-up of long-term survivors is essential. In this report, we review some selected late adverse effects including the development of secondary malignancies, cardiotoxicity, physiological changes to glandular tissue, hormonal and reproductive changes to germ cells, and neurocognitive changes. Furthermore, we compared the differences regarding late effects of normal tissues associated with the use of proton versus photon radiotherapy, a topic that has received a great deal of attention in pediatric cancer and is increasing in utilization in the United States and world-wide.

Acupuncture-Like Transcutaneous Electrical Nerve Stimulation Versus Pilocarpine in Treating Radiation-Induced Xerostomia: Results of RTOG 0537 Phase 3 Study.

PURPOSE AND OBJECTIVES: This report presents the analysis of the RTOG 0537 multicenter randomized study that compared acupuncture-like transcutaneous stimulation (ALTENS) with pilocarpine (PC) for relieving radiation-induced xerostomia. METHODS AND MATERIALS: Eligible patients were randomized to twice-weekly 20-minute ALTENS sessions for 24 sessions during 12 weeks or PC (5 mg 3 times daily for 12 weeks). The primary endpoint was the change in the University of Michigan Xerostomia-Related Quality of Life Scale (XeQOLS) scores from baseline to 9 months from randomization (MFR). Secondary endpoints included basal and citric acid primed whole salivary production (WSP), ratios of positive responders (defined as patients with ≥20% reduction in overall radiation-induced xerostomia symptom burden), and the presence of adverse events based on the Common Terminology Criteria for Adverse Events version 3. An intention-to-treat analysis was conducted. RESULTS: One hundred forty-eight patients were randomized. Only 96 patients completed the required XeQOLS and were evaluable at 9 MFR (representing merely 68.6% statistical power). Seventy-six patients were evaluable at 15 MFR. The median change in the overall XeQOLS in ALTENS and PC groups at 9 and 15 MFR were -0.53 and -0.27 (P=.45) and -0.6 and -0.47 (P=.21). The corresponding percentages of positive responders were 81% and 72% (P=.34) and 83% and 63% (P=.04). Changes in WSP were not significantly different between the groups. Grade 3 or less adverse events, mostly consisting of grade 1, developed in 20.8% of patients in the ALTENS group and in 61.6% of the PC group. CONCLUSIONS: The observed effect size was smaller than hypothesized, and statistical power was limited because only 96 of the recruited 148 patients were evaluable. The primary endpoint-the change in radiation-induced xerostomia symptom burden at 9 MFR-was not significantly different between the ALTENS and PC groups. There was significantly less toxicity in patients receiving ALTENS.

Dosimetric and radiobiologic comparison of 3D conformal, IMRT, VMAT and proton therapy for the treatment of early-stage glottic cancer.

BACKGROUND: This study aims to compare dosimetrically and radiobiologically 3D conformal, intensity modulated radiation therapy (IMRT), RapidArc (RA) volumetric modulated arc therapy and proton therapy techniques for early-stage glottic cancer. METHODS: Ten patients were retrospectively selected. Photon treatment planning was performed using Eclipse External Beam Planning, and proton planning was performed using CMS Xio. The minimum, mean and maximum dose values for planning target volume (PTV), mean and maximum dose values for organ at risk, % of volume of PTV receiving at least 95% of the prescription dose, and D20, D50 and D90 of carotid arteries were compared. Biological response models of tumour control probabilities and normal tissue complication probabilities were calculated. RESULTS: IMRT, RA and proton plans versus three-dimensional conformal radiotherapy (3D-CRT) plans consistently provided superior PTV coverage and decreased mean dose to the thyroid and carotid arteries. CONCLUSION: All these three modalities showed superiority with less variation among themselves compared with 3D-CRT plans. Clinical investigation is warranted to determine if these treatment approaches will translate into a reduction in radiation therapy-induced toxicities.

Feasibility and implementation of a literature information management system for human papillomavirus in head and neck cancers with imaging.

This work examines the feasibility and implementation of information service-orientated architecture (ISOA) on an emergent literature domain of human papillomavirus, head and neck cancer, and imaging. From this work, we examine the impact of cancer informatics and generate a full set of summarizing clinical pearls. Additionally, we describe how such an ISOA creates potential benefits in informatics education, enhancing utility for creating enduring digital content in this clinical domain.

Intensity modulated radiation therapy (IMRT) for the treatment of unicentric Castlemans disease: a case report and review of the use of radiotherapy in the literature.

BACKGROUND: Surgical resection is considered standard therapy for cases of resectable unicentric Castleman's disease (UCD). Unresectable cases of UCD do not have a consensus regarding the optimal treatment approach, but have utilized steroids, observation, chemotherapy, and radiotherapy. Here we discuss a patient presentation of UCD treated with an advanced radiotherapy technique, IMRT. CASE REPORT: A 47 year old female was found to have an intra-thoracic posterior UCD and was determined not to be a good surgical candidate. She was referred for radiotherapy and was treated using IMRT to a total dose of 4320 cGy in 180 cGy fractions including a scheduled 10 day break. Following the break, the patient's treatment was replanned at which the initial treatment volume was reduced by 50.9% for the duration of the treatment course. Radiation Therapy Oncology Group (RTOG) grade III pneumonitis developed which was managed medically. Neither disease progression nor late effects have occurred. CONCLUSIONS: The use of IMRT and planned treatment break was successful in the treatment of a case of UCD, and should be considered for other unresectable cases.

Use of stereotactic body radiation therapy for medically inoperable multiple primary lung cancer.

INTRODUCTION: To review outcomes of medically inoperable patients treated with stereotactic body radiation therapy (SBRT) for multiple primary lung cancer (MPLC). METHODS: We retrospectively reviewed the charts of 10 patients (21 lesions) treated with SBRT for synchronous (seven), metachronous (one) or synchronous/metachronous lung cancers. All patients were male, medically inoperable and had a median age of 66 years. Eight patients had bilateral disease and two had unilateral disease. All patients had a histological diagnosis in at least one of the two lesions and four patients (44.4%) had both lesions biopsied. There were 18 T1 lesions and three T2 lesions. SBRT was in three fractions of 20 Gy or five fractions of 11-12 Gy to each lesion. RESULTS: Mean and median follow up were 18.8 and 15.5 months, respectively. At analysis, six patients (60.0%) are alive, and five of these living patients (83.3%) have no evidence of disease recurrence or progression. Four patients (44.4%) developed distant metastatic disease. Twenty lesions (95.2%) achieved in-field local control. No patients experienced acute pulmonary complications and only two patients (22.2%) experienced late grade I lung toxicity as per the Radiation Therapy Oncology Group toxicity criteria. CONCLUSION: SBRT for MPLC in medically inoperable patients is a safe, feasible and effective treatment approach.

The efficacy of radiation therapy in the treatment of Graves' orbitopathy.

PURPOSE: To review our institutional outcomes of patients treated with radiation therapy (RT) for Graves' orbitopathy (GO), assess the role of orbital reirradiation, and identify prognostic factors of complete response (CR). METHODS AND MATERIALS: This is a retrospective review of 211 patients who presented with a diagnosis of GO and received RT between January 2000-2010. RT dose was 20 Gy in 10 fractions. Patient median age was 51 years (range, 15-84 years), median follow-up was 11 months (range, 1-88 months). Patient symptoms included any combination of proptosis (90.9%), extraocular muscle dysfunction (78.9%), soft tissue signs (68.4%), and diplopia (58.4%). Corticosteroids were used as first-line therapy in 20.6% of patients. Among those who achieved either CR or partial response (PR), prognostic factors were evaluated. RESULTS: Stabilization of disease without recurrence was clinically achieved overall in 202 patients (96.7%). At the completion of RT, 176 patients (84.2%) reported a symptomatic improvement of pretreatment symptoms. CR of GO symptoms was achieved using multiple treatment modalities, including RT by 93 patients (44.5%), of which 32 patients received RT only. Corticosteroids were discontinued in 97.8% of patients who received them as initial therapy. Surgical intervention following radiotherapy was required for 144 (68.9%) of all patients. Fourteen patients received orbital reirradiation for persistent or recurrent symptoms. Five of these achieved a CR, and the other nine achieved disease stabilization but retained persistent ocular symptoms. Long-term side effects of RT included dry eyes (12%). Of the prognostic factors we investigated, only gender predicted CR, which was less common in men (33.9%) than in women (49.7%) p = 0.0471. CONCLUSIONS: Orbital radiation for GO is an established treatment modality for patients. Orbital reirradiation is beneficial for patients who do not respond to initial RT or experience symptom recurrence without an apparent risk of increased morbidity.

The role of radiotherapy for T4 non-melanoma skin carcinoma.

INTRODUCTION: To review outcomes of patients treated with radiotherapy (RT) for T4 non-melanoma skin cancer (NMSC). METHODS: A retrospective chart review was performed of 21 patients who received RT for T4 NMSC from 2004 to 2010. Outcomes of treatment efficacy, RT technique and patient morbidity were analysed. Twelve patients (57.1%) were treated definitively without prior treatment, five (23.8%) were recurrent lesions and four (19.1%) were treated postoperatively. Ten patients (47.6%) had evidence of bony erosion at presentation, and four (19.1%) had nodal disease. Intensity-modulated radiotherapy (IMRT), three-dimensional conformal RT and electron treatment were included RT techniques. RESULTS: Median follow-up was 12 months (range, 5-48 months). Twelve patients (57.1%) following RT required no further treatment and had no disease recurrence. Three patients (14.3%) required salvage treatment and are disease-free following all treatment. Tumours treated initially or postoperatively had improved control rates following RT compared with recurrent lesions (58.3% and 100% vs. 20%). Sixty percent of patients treated with IMRT achieved local control following RT, and 80% were disease-free following surgical salvage treatment. Squamous cell carcinoma (SCC) histology, presence of bony erosion and/or nodal disease was associated with a higher incidence of disease recurrence. CONCLUSIONS: Patients presenting with untreated lesions, smaller tumour volumes (<70 cm(3)) postoperatively, basal cell histology and absence of bone erosion or nodal disease have improved local control and outcomes. Basal cell carcinoma and SCC should be staged and treated as two separate disease entities. The use of IMRT for advanced skin cancer warrants further investigation.

Linear accelerator based intracranial and extracranial stereotactic radiation therapy at the University of Oklahoma.

PURPOSE: Review our institutional outcomes with linear accelerator based stereotactic radiation therapy at the University of Oklahoma. METHODS: We retrospectively reviewed all patients treated in our department with linear accelerator based stereotactic radiation therapy since we implemented this modality in 2008. Thirty-seven patients have been treated with a mean follow-up of 8.3 months. Seventeen patients had tumors near critical structures; ten had treatment sites not suited for gamma knife therapy. Outcomes are reviewed for efficacy and toxicity. RESULTS: Acute and long term complications reported are minimal. Stabilization of treatment sites was achieved in 96% of patients on follow-up imaging. Thirteen patients (35%) have died, of which eleven died to systemic disease progression outside of the treatment site. No treatment related deaths occurred. CONCLUSIONS: Stereotactic radiation therapy is a successful treatment modality to achieve local disease control with minimal toxicity. We plan to expand its use and applications in the future.

The efficacy of radiotherapy in the treatment of orbital pseudotumor.

PURPOSE: To review institutional outcomes for patients treated with external-beam radiotherapy (EBRT) for orbital pseudotumor. METHODS AND MATERIALS: This is a single-institution retrospective review of 20 orbits in 16 patients diagnosed with orbital pseudotumor that received EBRT at the University of Oklahoma, Department of Radiation Oncology. Treated patients had a median follow-up of 16.5 months. RESULTS: Fifteen patients (93.7%) were initially treated with corticosteroids. Eight had recurrence after steroid cessation, six were unable to taper corticosteroids completely or partially, and one experienced progression of symptoms despite corticosteroid therapy. Fourteen patients (87.5%) initially responded to radiotherapy indicated by clinical improvement of preradiation symptoms and/or tapering of corticosteroid dose. Mean EBRT dose was 20 Gy (range, 14-30 Gy). Thirteen patients (81.2%) continued to improve after radiation therapy. Patient outcomes were complete cessation of corticosteroid therapy in nine patients (56.3%) and reduced corticosteroid dose in four patients (25%). Radiotherapy did not achieve long-term control for three patients (18.7%), who still required preradiation corticosteroid dosages. Three patients received retreatment(s) of four orbits, of which two patients achieved long-term symptom control without corticosteroid dependence. One patient received retreatment to an orbit three times, achieving long-term control without corticosteroid dependence. No significant late effects have been observed in retreated patients. CONCLUSIONS: Radiotherapy is an effective treatment for acute symptomatic improvement and long-term control of orbital pseudotumor. Orbital retreatment can be of clinical benefit, without apparent increase in morbidity, when initial irradiation fails to achieve complete response.

Radiotherapy in treatment of carcinoma of the parotid gland, an approach for the medically or technically inoperable patient.

INTRODUCTION: Initial surgical resection is considered the standard of care for patients diagnosed with tumours involving the salivary glands. We reviewed our institutional outcomes of patients treated with initial radiation therapy (RT) for diagnosed carcinoma of the parotid gland. METHODS: This review examined seventeen patients that received RT as initial therapy for tumours involving the parotid gland. Fifteen patients had primary salivary gland cancer, and two patients had metastatic carcinoma to the parotid gland. Sixteen patients (94.1%) following surgical evaluation had operative risk of facial nerve impairment or sacrifice with initial surgery, four (23.5%) had clinical objective evidence of nerve involvement at evaluation, five (29.4%) were poor surgical candidates and three (17.6%) refused initial surgery. Primary tumour stages ranged T2-T4b, and disease stages ranged II-IVb. RT median dose was 70 Gy, and median follow-up was 12 months. RESULTS: Eleven patients (64.7%) achieved a clinical complete response (CR) to therapy. Of these CR patients eight (72.7%) received definitive RT and three (27.3%) underwent surgery following RT. Two surgical patients avoided facial nerve impairment while one required nerve sacrifice. The other six patients (35.3%) achieved an unfavourable response to RT and had unresectable or metastatic disease at follow-up. No long-term complications were reported. CONCLUSION: Initial radiation therapy for tumours involving the parotid gland is effective to achieve clinical CR, eliminate surgical resection for many patients, and decrease risk of facial nerve impairment or sacrifice for those patients requiring surgery following RT.

Quantitative evaluation of increase in surface dose by immobilization thermoplastic masks and superficial dosimetry using Gafchromic EBT film and Monte Carlo calculations.

PURPOSE: To investigate the increase in surface dose under immobilization thermoplastic masks by measurements and calculation in the build-up region using Gafchromic films and Monte Carlo simulation. MATERIALS AND METHODS: Surface doses were measured underneath three thermoplastic masks in open fields using 6 and 18 MV photon beams. These masks are used to immobilize patients for head and neck (H&N), pelvis and thoracic treatment. Gafchromic EBT films were placed on the top of the flat surface of a phantom partially underneath the mask and exposed in open 10 x 10 cm2 photon fields. The depth doses were calculated using BEAMnrc Monte Carlo code for water-equivalent film detectors with different layers of thickness ranging from 50 microm to 2.5 mm and compared with film measurements. RESULTS: Surface dose increased by a factor of 3 to 4 underneath the mask relative to the open areas and 6 MV beam delivers more skin dose than 18 MV. H&N mask increased surface dose by a factor of 3 using 18 MV and a factor of 4 using 6 MV. In addition, increase in surface dose depended on the type of the mask, the size of openings, and the amount of stretching performed during the mask preparation. The measured depth doses were compared with BEAMnrc Monte Carlo calculation for water-equivalent detectors using different sizes. The calculated depth dose depended significantly on the thickness of film detector and varies by more than 15% using layer thickness of 2.5 mm compared to 50 microm. Surface doses measured by Gafchromic EBT films agreed within 3% with the Monte Carlo calculations using a small detector layer of 50 microm. CONCLUSION: Thermoplastic masks used for patient immobilization can significantly increase skin doses by up to a factor of 4 more than that without the mask using 6 MV beams. The skin reactions resulting from thermoplastic masks should be monitored and corrective measures should be taken during treatment such as partially removing the mask over skin areas with complications and optimizing the skin dose in IMRT planning. Gafchromic EBT films provide accurate skin dosimetry which agrees within 3% with Monte Carlo calculations. Gafchromic EBT film makes an excellent tool for measuring depth doses in the buildup region and these data can be applied for treatment planning calculations and IMRT optimization.

Using an advanced radiation therapy technique for T4 squamous cell carcinoma of the face.

BACKGROUND: Patients with locally advanced skin cancer often present an uncommon and unique treatment challenge. Surgical resection and reconstruction with an acceptable cosmetic outcome is difficult for larger lesions with deep infiltration into subcutaneous tissues. Radiation therapy has been shown to be an effective treatment modality for advanced non-melanoma skin cancers, with cure rates ranging 50-100%. In this case report, we discuss the efficacy and outcome of treatment using an advanced radiation therapy technique to a large T4 squamous cell carcinoma of the face. MAIN OBSERVATIONS: The patient responded favorably to the advanced radiation treatment course, and achieved a clinical complete response to therapy. No further intervention was required. Advanced radiation therapy techniques offered treatment advantages that resulted in greater tumor dose escalation and minimizing of patient morbidity. CONCLUSIONS: Patients with advanced skin cancers of the head and neck should be considered for definitive radiation therapy using advanced treatment techniques. The use of definitive RT only for tumors deemed unresectable, or for inoperable patients at presentation deserves reconsideration. Further investigation is warranted.