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e24082 Background: Palliative radiation therapy (PRT) is underutilized in the United States, in part due to misconceptions among patients and other providers about its risks, benefits, and indications. Empowered patients, who are more knowledgeable about how radiation can alleviate cancer-induced symptoms, may facilitate more appropriate and timely use of PRT. In this pilot study patient-directed educational material describing PRT was developed and used among patients being treated in medical oncology and palliative care clinics. The hypothesis is that most patients will gain new knowledge from educational content about PRT, and perceive it as useful in their care. Materials/Methods: A 1-page educational handout was developed to convey general information about the purpose, logistics, benefits, risks, and common indications for PRT. Patients undergoing treatment for a metastatic solid tumor were invited to participate during their regular clinic visit. Patients who chose to participate read the handout, and then completed a multiple choice questionnaire assessing how much they learned from the handout (nothing vs. little vs. lots), whether the information in the handout was useful (no vs. somewhat vs. very), as well as other questions. Responses were anonymous. There was no follow-up with participants. Descriptive statistics are reported, with Fisher’s Exact Test used to compare subgroups of patients. Results: A total of 70 patients from 1 palliative care physician and 4 medical oncologists participated between June – December 2021. Sixty-five patients (89%) felt they learned from the handout (38% learned “lots”) and 69 (94.5%) felt the information was useful (53% “very useful”). Twenty-one patients (28.8%) learned that PRT can help with symptom relief, 55 (75%) learned that PRT can be delivered in a course of 5 treatments or less, and 43 patients (59%) learned that PRT usually has few side effects. Furthermore, 16 (22%) felt they currently had symptoms not being treated well enough, and 34 (47%) felt they currently had symptoms that radiation might help with. Most patients felt more comfortable bringing symptoms to a medical oncologist’s (n = 57, 78%) or radiation oncologist’s (n = 51, 70%) attention after reading the handout. Forty-one patients (56.2%) reported a prior visit with a radiation oncologist, but this did not impact their responses related to learning from the handout ( p< 0.001) or finding the handout useful ( p< 0.001). Conclusions: Patient-directed educational material about PRT provided outside of a radiation oncology department was perceived by patients as improving their knowledge, and adding value in their care, independent of their prior exposure to a radiation oncologist. Further research will evaluate the impact of the educational material on referral patterns.

11050 Background: Industry partnerships offer financial incentives, prestige, and can facilitate career advancement in oncology. However, not all physicians may have equal access to these opportunities. We hypothesized that physicians who are underrepresented in the medical oncology workforce based on race, ethnicity, and gender receive less industry funding. Methods: All US medical oncologists (MOs) who received ≥1 industry research payment between 2016 and 2020 according to the Open Payments database were included in this retrospective study. Information extracted from Open Payments included MO’s name, institution, research payments (i.e. funding for a research project where the physician is a Principle Investigator), and general payments (i.e. fees not associated with research, such as consulting and travel fees). Additional web searches were conducted using institutional websites, NPPES NPI registry, LinkedIn, Doximity, Scopus, and NIH RePORTER to determine each MO’s race, ethnicity, sex, academic rank, degrees, h-index, institutional NIH research funding rank, and individual receipt of NIH funding. Log-linear regression was performed to identify associations of both industry and general payment data. Results: Of 7,542 physicians meeting inclusion criteria, 69% were male, 65% White, 29% Asian, 2% Black, and 4% Hispanic, which is comparable to the American Medical Association Physician Masterfile figures for MO. The median sum research payment and general payment was $134,857 and $11,537 per physician respectively. Significantly higher mean research payments were associated with an MS (+72%; P = 0.003) or PhD degree (+30%; P = 0.009), h-index (+3%; P < 0.001), top 50 institution rank by NIH funding (+44%; P < 0.001), and associate professor rank (+95%; P < 0.001). Significantly lower mean research payment were observed for Black physicians (-36%; P = 0.022) and those with non-academic affiliation (-47%; P < 0.001). No significant association was observed between sex and research payment. Significantly higher mean general payments were associated with male sex (+46%; P < 0.001), MS degree (+171%; P < 0.001), h-index (+2%; P < 0.001), and Asian race (+72%; P < 0.001). Significantly lower mean general payments were associated with an affiliation with a non-academic practice (-31%; P = 0.012). Conclusions: Black physicians received smaller sums of industry research payments compared to White physicians. Female sex was associated with decreased general payments compared to male sex. Further exploring the underlying mechanisms determining access to industry payments may help facilitate greater equity and inclusivity in oncology.

We have implemented and validated an algorithm for three-dimensional positron emission tomography transmission-to-computed tomography registration in the chest, using mutual information as a similarity criterion. Inherent differences in the two imaging protocols produce significant nonrigid motion between the two acquisitions. A rigid body deformation combined with localized cubic B-splines is used to capture this motion. The deformation is defined on a regular grid and is parameterized by potentially several thousand coefficients. Together with a spline-based continuous representation of images and Parzen histogram estimates, our deformation model allows closed-form expressions for the criterion and its gradient. A limited-memory quasi-Newton optimization algorithm is used in a hierarchical multiresolution framework to automatically align the images. To characterize the performance of the method, 27 scans from patients involved in routine lung cancer staging were used in a validation study. The registrations were assessed visually by two expert observers in specific anatomic locations using a split window validation technique. The visually reported errors are in the 0- to 6-mm range and the average computation time is 100 min on a moderate-performance workstation.

2-deoxy-2[(18)F]fluoro-D-glucose-positron emission tomography (FDG-PET) imaging can be registered with CT images and can potentially improve neck staging sensitivity and specificity in patients with head and neck squamous cell cancer. The intent of this study was to examine the use of registered FDG-PET/CT imaging to guide head and neck intensity modulated radiotherapy (IMRT) planning.Twenty patients with squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx underwent FDG-PET and contrast-enhanced CT imaging of the head and neck before neck dissection surgery. Combined FDG-PET/CT images were created by use of a nonrigid image registration algorithm. All IMRT plans were theoretical and were not used for treatment. We prescribed 66 Gy in 30 fractions to FDG-avid CT abnormalities and nodal zones directly involved with disease, without prophylactic coverage of uninvolved neck levels. Matched CT-guided IMRT plans designed according to the specifications of Radiation Therapy Oncology Group (RTOG) H-0022 were available for comparison. We investigated the feasibility of FDG-PET/CT-directed IMRT dose escalation in five patients with FDG-avid disease located away from critical normal structures. After 66 Gy, FDG-avid disease with 0.5-cm margins was boosted in 220 cGy increments until dose-limiting criteria were reached.Elimination of prophylactic coverage to FDG-PET/CT-negative neck levels markedly reduced mean dose (Dmean) to the contralateral parotid gland (p.001) and Dmean to the laryngeal cartilage (p = .001). No FDG-PET/CT-directed plan missed pathologically verified nodal disease. During the dose escalation exercise, we successfully increased the dose to 95% of the planning target volume (PTV95%) to a mean of 7490 cGy (range, 7153-8098 cGy).We demonstrate early proof of the principle that FDG-PET/CT-guided IMRT planning can selectively target and intensify treatment of head and neck disease while reducing critical normal tissue doses. Routine clinical use of such planning should not be engaged until the accuracy of FDG-PET/CT is fully validated. Future directions, including refinement of treatment to gross disease and radiologically uninvolved neck nodal levels, are discussed.

Purpose Image localization of head-and-neck squamous cell carcinoma lags behind current techniques to deliver a precise radiation dose with intensity-modulated radiotherapy. This pilot study prospectively examined the use of registered 18-F-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT for preradiotherapy staging of the neck. Methods and materials Sixty-three patients with squamous cell carcinoma of the oral cavity, oropharynx, larynx, or hypopharynx were enrolled into an institutional FDG-PET imaging protocol between September 2000 and June 2003. Of these patients, 20 went on to immediate neck dissection surgery and were studied further. Of these 20, 17 (85%) had American Joint Committee on Cancer Stage III or IV disease. All patients underwent preoperative FDG-PET and contrast-enhanced CT of the head and neck. FDG-PET/CT images were created using a nonrigid image registration algorithm developed at the University of Washington. Alternate primary and nodal gross tumor volumes were contoured with radiotherapy treatment planning software, blinded to each other and to the pathology results. One set of volumes was designed with CT guidance alone and the other with the corresponding FDG-PET/CT images. Neck dissection specimens were subdivided into surgical nodal levels intraoperatively, and the histopathologic findings were correlated with the CT and FDG-PET/CT nodal level findings. Results FDG-PET/CT detected 17 of 17 heminecks and 26 of 27 nodal zones histologically positive by dissection (100% and 96% sensitivity, respectively). The nodal level staging sensitivity and specificity for FDG-PET/CT was 96% (26 of 27) and 98.5% (68 of 69), respectively. FDG-PET/CT correctly detected nodal disease in 2 patients considered to have node-negative disease by CT alone. Agreement between the imaging results and pathology findings was stronger for FDG-PET/CT (κ 0.95, 95% confidence interval 0.82–0.99) than for CT alone (κ 0.81, 95% confidence interval 0.63–0.91; p = 0.06 by two-sided McNemar's testing). Conclusion These early findings suggest that FDG-PET/CT is superior to CT alone for geographic localization of diseased neck node levels. Confirmatory trials to substantiate the accuracy of FDG-PET/CT neck staging should be prioritized.

As the transition toward total digital image acquisition continues, radiology is transcending the current standard of two-dimensional (2-D) cross-sectional anatomic imaging to more complex models. Among these are three-dimensional (3-D) anatomic images, constructed either from a synthesis of traditional 2-D data sets, or directly from volumetrically acquired data. However, current trends are moving beyond mere anatomic imaging to include physiological data once mainly obtained via nuclear medicine. Recent magnetic resonance pulse sequences, in addition to Doppler and harmonic ultrasound methods, are providing insight into blood flow, oxygenation, and metabolite concentrations non-invasively. Through image registration techniques, these data (even from differing modalities) are being assembled into 2-D and 3-D "fusion" images that promise to revolutionize diagnosis. Furthermore, with improvements in miniaturization, reliability, speed, built-in intelligence, and ease of use, these new developments are finding their way into use by nonspecialists. For instance, a new hand-held ultrasound unit will likely become a common tool among emergency medical teams, military medical teams, and in NASA's manned space program. Portable computed tomography (CT) scanners are already being used in the operating room. The increasing sophistication of imaging instruments will bring about a complementary increase in ease of use for both scanning and data interpretation, bringing diagnostic imaging and therapeutic capabilities closer to the patient, rather than the converse.

We have designed, implemented, and validated an algorithm capable of 3D PET-CT registration in the chest, using mutual information as a similarity criterion. Inherent differences in the imaging protocols produce significant non-linear motion between the two acquisitions. To recover this motion, local deformations modeled with cubic B-splines are incorporated into the transformation. The deformation is defined on a regular grid and is parameterized by potentially several thousand coefficients. Together with a spline-based continuous representation of images and Parzen histogram estimates, the deformation model allows for closed-form expressions of the criterion and its gradient. A limited-memory quasi-Newton optimization package is used in a hierarchical multiresolution framework to automatically align the images. To characterize the performance of the algorithm, 27 scans from patients involved in routine lung cancer screening were used in a validation study. The registrations were assessed visually by two observers in specific anatomic locations using a split window validation technique. The visually reported errors are in the 0-6mm range and the average computation time is 100 minutes.