Principal component analysis modeling of Head-and-Neck anatomy using daily Cone Beam-CT images.

PURPOSE: To model Head-and-Neck anatomy from daily Cone Beam-CT (CBCT) images over the course of fractionated radiotherapy using principal component analysis (PCA). METHODS AND MATERIALS: Eighteen oropharyngeal Head-and-Neck cancer patients, treated with volumetric modulated arc therapy (VMAT), were included in this retrospective study. Normal organs, including the parotid and submandibular glands, mandible, pharyngeal constrictor muscles (PCMs), and spinal cord were contoured using daily CBCT image datasets. PCA models for each organ were developed for individual patients (IP) and the entire patient cohort/population (PP). The first 10 principal components (PCs) were extracted for all models. Analysis included cumulative and individual PCs for each organ and patient, as well as the aggregate organ/patient population; comparisons were made using the root-mean-square (RMS) of the percentage predicted spatial displacement for each PC. RESULTS: Overall, spatial displacement prediction was achieved at the 95% confidence level (CL) for the first three to four PCs for all organs, based on IP models. For PP models, the first four PCs predicted spatial displacement at the 80%-89% CL. Differences in percentage predicted spatial displacement between mean IP models for each organ ranged from 2.8% ± 1.8% (1st PC) to 0.6% ± 0.4% (4th PC). Differences in percentage predicted spatial displacement between IP models vs the mean IP model for each organ based on the 1st PC were <12.9% ± 6.9% for all organs. Differences in percentage predicted spatial displacement between IP and PP models based on all organs and patients for the 1st and 2nd PC were <11.7% ± 2.2%. CONCLUSION: Tissue changes during fractionated radiotherapy observed on daily CBCT in patients with Head-and-Neck cancers, were modeled using PCA. In general, spatial displacement for organs-at-risk was predicted for the first 4 principal components at the 95% confidence levels (CL), for individual patient (IP) models, and at the 80%-89% CL for population-based patient (PP) models. The IP and PP models were most predictive of changes in glandular organs and pharyngeal constrictor muscles, respectively.

Recommended patient-reported core set of symptoms to measure in head and neck cancer treatment trials.

We identified a standard core set of patient-reported symptoms and health-related quality-of-life (HRQOL) domains to be assessed in head and neck (H&N) cancer clinical trials. The core symptom and HRQOL domain scores were used to guide recommendations by a working group of experts as part of a National Cancer Institute Symptom Management and HRQOL Clinical Trials Planning Meeting. A PubMed search was conducted using the search terms of "health-related quality of life" and "head & neck cancer," limited to publications from January 1, 2000, to December 31, 2010. Fifty-four articles were used to guide the choice of recommendations. Twenty-nine symptoms and nine domains were identified, from which 12 H&N-specific core symptoms and HRQOL domains were recommended: swallowing, oral pain, skin changes, dry mouth, dental health, opening mouth/trismus, taste, excess/thick mucous/saliva, shoulder disability/motion, voice/hoarseness, social domain, and functional domain. This core set of 12 H&N-specific, patient-reported symptoms and HRQOL domains should be assessed in future H&N cancer clinical trials.

Symptom clusters in patients with head and neck cancer receiving concurrent chemoradiotherapy.

OBJECTIVES: This study is to identify symptom clusters for head and neck (HNC) patients treated with concurrent chemoradiotherapy. PATIENTS AND METHODS: A secondary data analysis of 684 HNC patients treated on the Radiation Therapy Oncology Group (RTOG) 0129 trial comparing different RT fractionation schedules with concurrent chemotherapy was used to examine clusters. Treatment-related symptoms were measured by clinicians at three time-points during and after chemoradiotherapy using the National Cancer Institute Common Toxicity Criteria v2.0. Exploratory factor analysis was applied to identify symptom clusters, which was further verified by confirmatory factor analysis. Coefficients of congruence and alpha coefficients were employed to examine generalizability of cluster structures over different time-points and in different subgroups. RESULTS: Two clusters were identified. The HNC specific cluster is composed of radiodermatitis, dysphagia, radiomucositis, dry mouth, pain, taste disturbance, and fatigue. The gastrointestinal (GI) cluster involves nausea, vomiting, and dehydration. With the exception of patients 65years old or older, diagnosed with larynx cancer, or with stage III cancer, the two clusters were generalizable to different subgroups defined by age, gender, race, education, marital status, history of tobacco use, treatments, primary sites, disease stages, and tube feedings, as well as to the three symptom assessment time-points. CONCLUSIONS: The data provides preliminary support for two stable clusters in patients with HNC. These findings may serve to inform the symptom management in clinical practice. Moreover, the findings necessitate future research to examine the generalizability of identified clusters in the late symptom phase or other treatment modalities, and to understand the underlying biological mechanism.

Transoral resection of pharyngeal cancer: summary of a National Cancer Institute Head and Neck Cancer Steering Committee Clinical Trials Planning Meeting, November 6-7, 2011, Arlington, Virginia.

Recent advances now permit resection of many pharyngeal tumors through the open mouth, an approach that can greatly reduce the morbidity of surgical exposure. These transoral techniques are being rapidly adopted by the surgical community and hold considerable promise. On November 6-7, 2011, the National Cancer Institute sponsored a Clinical Trials Planning Meeting to address how to further investigate the use of transoral surgery, both in the good prognosis human papillomavirus (HPV)-initiated oropharyngeal cancers, and in those with HPV-unrelated disease. The proceedings of this meeting are summarized.