3D-conformal-intensity modulated radiotherapy with compensators for head and neck cancer: clinical results of normal tissue sparing

BACKGROUND: To investigate the potential of parotic gland sparing of intensity modulated radiotherapy (3D-c-IMRT) performed with metallic compensators for head and neck cancer in a clinical series by analysis of dose distributions and clinical measures. MATERIALS AND METHODS: 39 patients with squamous cell cancer of the head and neck irradiated using 3D-c-IMRT were evaluable for dose distribution within PTVs and at one parotid gland and 38 patients for toxicity analysis. 10 patients were treated primarily, 29 postoperatively, 19 received concomittant cis-platin based chemotherapy, 20 3D-c-IMRT alone. Initially the dose distribution was calculated with Helax (® )and photon fluence was modulated using metallic compensators made of tin-granulate (n = 22). Later the dose distribution was calculated with KonRad (® )and fluence was modified by MCP 96 alloy compensators (n = 17). Gross tumor/tumor bed (PTV 1) was irradiated up to 60–70 Gy, [5 fractions/week, single fraction dose: 2.0–2.2 (simultaneously integrated boost)], adjuvantly irradiated bilateral cervical lymph nodes (PTV 2) with 48–54 Gy [single dose: 1.5–1.8]). Toxicity was scored according the RTOG scale and patient-reported xerostomia questionnaire (XQ). RESULTS: Mean of the median doses at the parotid glands to be spared was 25.9 (16.3–46.8) Gy, for tin graulate 26 Gy, for MCP alloy 24.2 Gy. Tin-granulate compensators resulted in a median parotid dose above 26 Gy in 10/22, MCP 96 alloy in 0/17 patients. Following acute toxicities were seen (°0–2/3): xerostomia: 87%/13%, dysphagia: 84%/16%, mucositis: 89%/11%, dermatitis: 100%/0%. No grade 4 reaction was encountered. During therapy the XQ forms showed °0–2/3): 88%/12%. 6 months postRT chronic xerostomia °0–2/3 was observed in 85%/15% of patients, none with °4 xerostomia. CONCLUSION: 3D-c-IMRT using metallic compensators along with inverse calculation algorithm achieves sufficient parotid gland sparing in virtually all advanced head and neck cancers. Since the concept of lower single (and total) doses in the adjuvantly treated volumes reduces acute morbidity 3D-c-IMRT nicely meets demands of concurrent chemotherapy protocols

Imaging in Radiation Oncology: A Perspective

This paper reviews the integration of imaging and radiation oncology, and discusses challenges and opportunities for improving the practice of radiation oncology with imaging

Intensity-modulated radiation therapy: emerging cancer treatment technology

The use of intensity-modulated radiation therapy (IMRT) is rapidly advancing in the field of radiation oncology. Intensity-modulated radiation therapy allows for improved dose conformality, thereby affording the potential to decrease the spectrum of normal tissue toxicities associated with IMRT. Preliminary results with IMRT are quite promising; however, the clinical data is relatively immature and overall patient numbers remain small. High-quality IMRT requires intensive physics support and detailed knowledge of three-dimensional anatomy and patterns of tumour spread. This review focuses on basic principles, and highlights the clinical implementation of IMRT in head and neck and prostate cancer

Safety considerations for IMRT: Executive summary

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/98742/1/MPH005067.pd

Ipsilateral irradiation for well lateralized carcinomas of the oral cavity and oropharynx: results on tumor control and xerostomia

<p>Abstract</p> <p>Background</p> <p>In head and neck cancer, bilateral neck irradiation is the standard approach for many tumor locations and stages. Increasing knowledge on the pattern of nodal invasion leads to more precise targeting and normal tissue sparing. The aim of the present study was to evaluate the morbidity and tumor control for patients with well lateralized squamous cell carcinomas of the oral cavity and oropharynx treated with ipsilateral radiotherapy.</p> <p>Methods</p> <p>Twenty consecutive patients with lateralized carcinomas of the oral cavity and oropharynx were treated with a prospective management approach using ipsilateral irradiation between 2000 and 2007. This included 8 radical oropharyngeal and 12 postoperative oral cavity carcinomas, with Stage T1-T2, N0-N2b disease. The actuarial freedom from contralateral nodal recurrence was determined. Late xerostomia was evaluated using the European Organization for Research and Treatment of Cancer QLQ-H&N35 questionnaire and the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 3.</p> <p>Results</p> <p>At a median follow-up of 58 months, five-year overall survival and loco-regional control rates were 82.5% and 100%, respectively. No local or contralateral nodal recurrences were observed. Mean dose to the contralateral parotid gland was 4.72 Gy and to the contralateral submandibular gland was 15.30 Gy. Mean score for dry mouth was 28.1 on the 0-100 QLQ-H&N35 scale. According to CTCAE v3 scale, 87.5% of patients had grade 0-1 and 12.5% grade 2 subjective xerostomia. The unstimulated salivary flow was > 0.2 ml/min in 81.2% of patients and 0.1-0.2 ml/min in 19%. None of the patients showed grade 3 xerostomia.</p> <p>Conclusion</p> <p>In selected patients with early and moderate stages, well lateralized oral and oropharyngeal carcinomas, ipsilateral irradiation treatment of the primary site and ipsilateral neck spares salivary gland function without compromising loco-regional control.</p

Radiation-Induced Sarcomas of the Head and Neck : A Systematic Review

Introduction As a result of the increased use of radiotherapy (RT) and improved long-term overall survival of patients with cancers of the head and neck (HN), the frequency of radiation-induced sarcomas of the head and neck (RISHN) may be increasing. The main objective of this systematic review was to determine the existing evidence on the frequency, treatment, and outcome of RISHN. Methods Using PRISMA guidelines we conducted a systematic review of the literature published from 2000 to 2020. Results Our review includes data of 560 patients from 64 articles. The total frequency of RISHNs among the reviewed series was 0.15%. The most frequent location of the primary tumor treated by RT was the nasopharynx. The mean RT dose used was 62 Gy, mean latency interval between irradiation and occurrence of RISHN was 11.1 years, and the most common RISHN location was the sinonasal region. Osteosarcoma was the principal histology, followed by fibrosarcoma. Surgery was the most frequently applied treatment modality. Of all patients with RISHN, 40.7% died of this disease after a mean interval of 13.9 months. Conclusions Notwithstanding the increased use of RT, the number of reported RISHNs has not increased substantially during the past two decades. Surgery with wide margins forms the best therapeutic option for these cases, but the outcome remains poor.Peer reviewe

Unilateral versus bilateral nodal irradiation:Current evidence in the treatment of squamous cell carcinoma of the head and neck

Cancers of the head and neck region often present with nodal involvement. There is a long-standing convention within the community of head and neck radiation oncology to irradiate both sides of the neck electively in almost all cases to include both macroscopic and microscopic disease extension (so called elective nodal volume). International guidelines for the selection and delineation of the elective lymph nodes were published in the early 2000s and were updated recently. However, diagnostic imaging techniques have improved the accuracy and reliability of nodal staging and as a result, small metastases that used to remain undetected and were thus in the past included in the elective nodal volume, will now be included in high-dose volumes. Furthermore, the elective nodal areas are situated close to the parotid glands, the submandibular glands and the swallowing muscles. Therefore, irradiation of a smaller, more selected volume of the elective nodes could reduce treatment-related toxicity. Several researchers consider the current bilateral elective neck irradiation strategies an overtreatment and show growing interest in a unilateral nodal irradiation in selected patients. The aim of this article is to give an overview of the current evidence about the indications and benefits of unilateral nodal irradiation and the use of SPECT/CT-guided nodal irradiation in squamous cell carcinomas of the head and neck

Outcome in recurrent head neck cancer treated with salvage-IMRT

BACKGROUND: Recurrent head neck cancer (rHNC) is a known unfavourable prognostic condition. The purpose of this work was to analyse our rHNC subgroup treated with salvage-intensity modulated radiation therapy (IMRT) for curable recurrence after initial surgery alone. Patients Between 4/2003-9/2008, 44 patients with squamous cell rHNC were referred for IMRT, mean/median 33/21 (3-144) months after initial surgery. None had prior head neck radiation. 41% underwent definitive, 59% postoperative IMRT (66-72.6Gy). 70% had simultaneous chemotherapy. METHODS: Retrospective analysis of the outcome following salvage IMRT in rHNC patients was performed. RESULTS: After mean/median 25/21 months (3-67), 22/44 (50%) patients were alive with no disease; 4 (9%) were alive with disease. 18 patients (41%) died of disease. Kaplan Meier 2-year disease specific survival (DSS), disease free survival (DFS), local and nodal control rates of the cohort were 59/49/56 and 68%, respectively. Known risk factors (advanced initial pTN, marginal initial resection, multiple recurrences) showed no significant outcome differences. Risk factors and the presence of macroscopic recurrence gross tumor volume (rGTV) in oral cavity patients vs others resulted in statistically significantly lower DSS (30 vs 70% at 2 years, p=0.03). With respect to the assessed unfavourable outcome following salvage treatment, numbers needed to treat to avoid one recurrence with initial postoperative IMRT have, in addition, been calculated. CONCLUSION: A low salvage rate of only ~50% at 2 years was found. Calculated numbers of patients needed to treat with postoperative radiation after initial surgery, in order to avoid recurrence and tumor-specific death, suggest a rather generous use of adjuvant irradiation, usually with simultaneous chemotherapy

The influence of pre-radiation salivary flow rates and radiation dose on parotid salivary gland dysfunction in patients receiving radiotherapy for head and neck cancers

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72238/1/j.1754-4505.1998.tb00913.x.pd