Joshua A. Asper

Parathyroid carcinoma: A 22-year experience

Because parathyroid carcinoma is rare, clear consensus is not available regarding the optimal management of patients with this condition. Treatment strategies generally derive from clinical and anecdotal experiences. We report our experience with this entity.

Measuring head and neck cancer symptom burden: The development and validation of the M. D. Anderson symptom inventory, head and neck module

The aim of this study was to develop and validate a symptom inventory for patients with head and neck cancer and to assess the occurrence and severity of symptoms, the overall symptom burden, and the interference the symptoms cause in daily life.

Is concurrent chemoradiation the treatment of choice for all patients with Stage III or IV head and neck carcinoma

Many patients with small primary tumors of the oropharynx have AJCC Stage III/IV disease on the basis of lymphadenopathy. In the current retrospective study, the authors hypothesized that these patients have high rates of locoregional control when treated with radiotherapy, either alone or combined with neck surgery, and may not require concurrent chemotherapy.

IMPORTANCE OF PATIENT EXAMINATION TO CLINICAL QUALITY ASSURANCE IN HEAD AND NECK RADIATION ONCOLOGY

When quality assurance programs in clinical radiation oncology focus mainly on the technical aspects of treatment, they tend to underplay questions of therapeutic process and outcome. We determined the value of clinical peer review in radiation therapy for head and neck cancer that involved head and neck examination.

The effect of dental artifacts, contrast media, and experience on interobserver contouring variations in head and neck anatomy

Objectives:To investigate interobserver variability in the delineation of head-and-neck (H&N) anatomic structures on CT images, including the effects of image artifacts and observer experience. Methods:Nine observers (7 radiation oncologists, 1 surgeon, and 1 physician assistant) with varying levels of H&N delineation experience independently contoured H&N gross tumor volumes and critical structures on radiation therapy treatment planning CT images alongside reference diagnostic CT images for 4 patients with oropharynx cancer. Image artifacts from dental fillings partially obstructed 3 images. Differences in the structure volumes, center-of-volume positions, and boundary positions (1 SD) were measured. In-house software created three-dimensional overlap distributions, including all observers. The effects of dental artifacts and observer experience on contouring precision were investigated, and the need for contrast media was assessed. Results:In the absence of artifacts, all 9 participants achieved reasonable precision (1 SD ≤3 mm all boundaries). The structures obscured by dental image artifacts had larger variations when measured by the 3 metrics (1 SD = 8 mm cranial/caudal boundary). Experience improved the interobserver consistency of contouring for structures obscured by artifacts (1 SD = 2 mm cranial/caudal boundary). Conclusions:Interobserver contouring variability for anatomic H&N structures, specifically oropharyngeal gross tumor volumes and parotid glands, was acceptable in the absence of artifacts. Dental artifacts increased the contouring variability, but experienced participants achieved reasonable precision even with artifacts present. With a staging contrast CT image as a reference, delineation on a noncontrast treatment planning CT image can achieve acceptable precision.

Impact of changes to the American Joint Committee on Cancer T classification on outcome prediction in patients with oropharyngeal cancer

The efficacy of the current 6th edition of the American Joint Committee on Cancer (AJCC) tumor staging criteria in improving outcome prediction for patients with oropharyngeal cancer was analyzed.

TU‐C‐ValB‐08: Modeling Dose Delivery Accuracy of IMRT Head‐And‐Neck Cancer Treatment

Purpose: To evaluate the impact of internal organ variations on IMRT treatments of head‐and‐neck cancers using different daily alignment techniques. Method and Materials: Eleven head‐and‐neck cancer patients were imaged twice weekly during their course of treatment (141 CT scans total) using an integrated CT‐linear accelerator (EXaCT, Varian Oncology Systems). The clinical IMRT plans were copied onto the daily CTimages. The plans were aligned with (1) the daily marked isocenter using three radio‐opaque markers (BBs) and (2) bone alignment, using in‐house software to align the cervical vertebrae. Daily dose distributions were mapped from the daily CTimages onto the planning CTimage with an in‐house deformable image registration algorithm. Cumulative dose‐volume histograms from the planning CTimage were analyzed.Results: The differences in the clinical target volumes (CTV) gEUD between the planned and delivered doses (with BB or bone alignment) were typically ⩽1Gy; therefore the differences in target coverage were most likely clinically insignificant. However, the alignment method did have a statistically significant impact on the percentage‐volume of the CTV at the prescription dose. Neither BB alignment nor bone alignment maintained the planned coverage (average=98.2%), which was reduced to 95.6% with bone alignment (p=0.000) and 94.3% with BB alignment (p=0.000). BB alignment significantly increased the average percentage‐volume receiving ⩾25Gy above the original plan for the ipsilateral (59.6% vs. 51.4%, p=0.003) and contralateral (42.0% vs. 36.4%, p=0.016) parotid glands. The parotid gland gEUD increased by more than 5Gy in 35% of BB alignments and 15% of bone alignments. However, there was no statistically significant difference between BB and bone alignments in parotid dose received. Conclusions: The differences in CTV coverage between bone and BB alignment were statistically significant but small. Bone alignment more closely reproduced the planned parotid dose than BB alignment, although both gave higher dose than the original plan.