Accuracy and efficiency of respiratory gating comparable to deep inspiration breath hold for pancreatic cancer treatment.

PURPOSE: Deep inspiration breath hold (DIBH) and respiratory gating (RG) are widely used to reduce movement of target and healthy organs caused by breathing during irradiation. We hypothesized that accuracy and efficiency comparable to DIBH can be achieved with RG for pancreas treatment. METHODS AND MATERIALS: Twenty consecutive patients with pancreatic cancer treated with DIBH (eight) or RG (twelve) volumetric modulated arc therapy during 2017-2019 were included in this study, with radiopaque markers implanted near or in the targets. Seventeen patients received 25 fractions, while the other three received 15 fractions. Only patients who could not tolerate DIBH received RG treatment. While both techniques relied on respiratory signals from external markers, internal target motions were monitored with kV X-ray imaging during treatment. A 3-mm external gating window was used for DIBH treatment; RG treatment was centered on end-expiration with a duty cycle of 40%, corresponding to an external gating window of 2-3 mm. During dose delivery, kV images were automatically taken every 20◦ or 40◦ gantry rotation, from which internal markers were identified. The marker displacement from their initial positions and the residual motion amplitudes were calculated. For the analysis of treatment efficiency, the treatment time of every session was calculated from the motion management waveform files recorded at the treatment console. RESULTS: Within one fraction, the displacement was 0-5 mm for DIBH and 0-6 mm for RG. The average magnitude of displacement for each patient during the entire course of treatment ranged 0-3 mm for both techniques. No statistically significant difference in displacement or residual motion was observed between the two techniques. The average treatment time was 15 min for DIBH and 17 min for RG, with no statistical significance. CONCLUSIONS: The accuracy and efficiency were comparable between RG and DIBH treatment for pancreas irradiation. RG is a feasible alternative strategy to DIBH.

Intrafraction tumor motion during deep inspiration breath hold pancreatic cancer treatment.

PURPOSE: Beam gating with deep inspiration breath hold (DIBH) has been widely used for motion management in radiotherapy. Normally it relies on some external surrogate for estimating the internal target motion, while the exact internal motion is unknown. In this study, we used the intrafraction motion review (IMR) application to directly track an internal target and characterized the residual motion during DIBH treatment for pancreatic cancer patients through their full treatment courses. METHODS AND MATERIALS: Eight patients with pancreatic cancer treated with DIBH volumetric modulated arc therapy in 2017 and 2018 were selected for this study, each with some radiopaque markers (fiducial or surgical clips) implanted near or inside the target. The Varian Real-time Position Management (RPM) system was used to monitor the breath hold, represented by the anterior-posterior displacement of an external surrogate, namely reflective markers mounted on a plastic block placed on the patient's abdomen. Before each treatment, a cone beam computed tomography (CBCT) scan under DIBH was acquired for patient setup. For scan and treatment, the breath hold reported by RPM had to lie within a 3 mm window. IMR kV images were taken every 20° or 40° gantry rotation during dose delivery, resulting in over 5000 images for the cohort. The internal markers were manually identified in the IMR images. The residual motion amplitudes of the markers as well as the displacement from their initial positions located in the setup CBCT images were analyzed. RESULTS: Even though the external markers indicated that the respiratory motion was within 3 mm in DIBH treatment, significant residual internal target motion was observed for some patients. The range of average motion was from 3.4 to 7.9 mm, with standard deviation ranging from 1.2 to 3.5 mm. For all patients, the target residual motions seemed to be random with mean positions around their initial setup positions. Therefore, the absolute target displacement relative to the initial position was small during DIBH treatment, with the mean and the standard deviation 0.6 and 2.9 mm, respectively. CONCLUSIONS: Internal target motion may differ from external surrogate motion in DIBH treatment. Radiographic verification of target position at the beginning and during each fraction is necessary for precise RT delivery. IMR can serve as a useful tool to directly monitor the internal target motion.

Assessment of Patients With Prostate Cancer and Their Understanding of the International Prostate Symptom Score Questionnaire.

Purpose: The International Prostate Symptom Score (IPSS) is a widely used tool for evaluating patient-reported lower urinary tract symptoms. In this study, we assessed patients with prostate cancer and their understanding of IPSS questions. Methods and Materials: Consecutive patients with prostate cancer (N = 144) self-completed an online IPSS questionnaire within 1 week before their visit at our radiation oncology clinic. At the visit, a nurse reviewed each IPSS question to ensure the patient understood it and then verified the patient's answer. Preverified and nurse-verified scores were recorded and analyzed for discrepancies. Results: Complete concordance between preverified and nurse-verified responses to individual IPSS questions existed for 70 men (49%). In terms of overall IPSS score, 61 men (42%) had a lower or improved IPSS after nurse verification, and 9 men (6%) had a higher or worse IPSS. Before verification, patients overstated their symptoms of frequency, intermittency, and incomplete emptying. As a result of the nurse verification, 4 of 7 patients with IPSS in the severe range (20-35) were recategorized to the moderate range (8-19). Sixteen percent of patients whose preverified IPSS were in the moderate range were recategorized after nurse verification to the mild range (0-7). Treatment option eligibility changed for 10% of patients after nurse verification. Conclusions: Patients frequently misunderstand the IPSS questionnaire, leading them to respond in ways that do not accurately reflect their symptoms. Clinicians should verify patient understanding of the IPSS questions, particularly when using the score to determine eligibility for treatments.

ACR Appropriateness Criteria® postoperative adjuvant therapy in non-small cell lung cancer.

Therapeutic options for postoperative adjuvant treatment for patients with non-small cell lung cancer (NSCLC) continue to evolve, and may include postoperative radiotherapy (PORT) and chemotherapy, alone or in combination. The use of platinum-based adjuvant chemotherapy has been demonstrated to confer an improvement in overall survival in patients with completely resected, stage N1 or N2 NSCLC, in several randomized trials and 2 meta-analyses. Consideration may also be given to adjuvant chemotherapy in patients with node-negative NSCLC, when the primary tumor is >4 cm, based on subset analyses of recent prospective studies. The precise role of PORT is less well defined. Older randomized studies indicated that the toxicity of PORT outweighed the potential improvement in local control, but studies using more modern radiation techniques show significantly reduced toxicity, inferring that select patients may benefit. Relative indications for PORT include the presence of mediastinal lymph nodes, positive surgical margins, and considerations with regard to the extent and type of resection. This study by the lung cancer expert panel of the American College of Radiology summarizes the recent evidence-based literature that addresses the use of postoperative adjuvant radiotherapy and chemotherapy in patients with NSCLC, illustrated with clinical scenarios. The sequencing of radiotherapy and chemotherapy is discussed, along with issues regarding radiotherapy dose and fractionation, and the appropriate use of intensity modulated radiation therapy and particle therapy.

ACR Appropriateness Criteria® on Induction and Adjuvant Therapy for Stage N2 Non-Small-Cell Lung Cancer: expert panel on radiation oncology-lung.

"The American College of Radiology seeks and encourages collaboration with other organizations on the development of the ACR Appropriateness Criteria through society representation on expert panels. Participation by representatives from collaborating societies on the expert panel does not necessarily imply society endorsement of the final document."

ACR Appropriateness Criteria: nonsurgical treatment for non-small-cell lung cancer: good performance status/definitive intent.

The optimal strategy for the non-surgical definitive treatment of patients with good performance status non-small cell lung cancer (mostly with locally advanced disease) has dramatically evolved over time. This article presents evidence-based data to review this literature. Several decades ago, the standard treatment for most stage III inoperable NSCLC was definitive radiation therapy alone. Randomized trials have since shown superior results with sequential chemotherapy and radiation, and more recently with concurrent chemoradiation, the current standard of care. Studies suggest a limited role for induction or adjuvant systemic therapy in addition to concurrent chemoradiation. The role of altered radiation fractionation techniques, such as hyperfractionation for locally advanced disease or hypofractionation for early stage disease is also discussed. More recently, the application of more advanced radiation techniques has been explored, including intensity modulated radiation therapy (IMRT) and proton beam radiation. Finally, various case variants are presented as examples of state-of-the-art treatment approaches.

ACR appropriateness criteria on nonsurgical treatment for non-small-cell lung cancer: poor performance status or palliative intent.

Radiation therapy (RT) plays a major role in the definitive treatment of patients with non-small-cell lung cancer who are unable to tolerate surgery. Radiation therapy alone is used primarily for early-stage (stages I and II) patients. Higher doses of RT (>65 Gy) seem to improve outcomes, and modern techniques such as stereotactic body RT have been very promising. For patients with locally advanced disease (stages IIIA and IIIB), concurrent chemotherapy and RT remains the standard of care. However, many patients cannot tolerate the regimen because of its toxicity. Sequential chemotherapy followed by RT is used in these situations. Radiation therapy alone is used for the rare patient who cannot tolerate the use of any chemotherapy because of comorbid conditions. Palliative external-beam RT is useful for patients with metastatic disease, causing symptoms such as dyspnea, cough, hemoptysis, postobstructive pneumonia, and pain. Hypofractionation has been attempted as a means to provide more rapid and convenient symptom relief, but results from clinical trials are conflicting on whether it is an improvement over standard palliative fractionation. Endobronchial brachytherapy provides relief for patients with endobronchial lesions causing obstruction or hemoptysis. Palliative chemotherapy improves survival and quality of life in patients with metastatic disease compared with best supportive care. Chemotherapy also improves outcomes as a second-line and third-line treatment for patients in whom previous regimens have failed. Biologic therapies such as erlotinib and bevacizumab have been incorporated into every phase of chemotherapy with good results.

Ovarian repositioning in pediatric cancer patients: Flexible techniques accommodate pelvic radiation fields.

Treatments for childhood cancer and consequent long-term survival rates continue to improve. As the success of these therapies advances, premature ovarian failure and sterility have become an increasingly evident long-term morbidity. Abdominal and pelvic radiation have been specifically shown to induce early menopause and decreased fertility. In order to minimize radiation injury, we utilized novel techniques to reposition ovaries in two girls with pelvic tumors prior to initiation of pelvic radiation. One girl with a sacral Ewing sarcoma underwent laparoscopic anterior suspension of the ovaries, using a simple and easily reversible technique. The second patient, who underwent hysterectomy for a recurrent uterine rhabdomyosarcoma, underwent widely lateral and cephalad repositioning of the ovaries. Both procedures were well tolerated, with no significant morbidity. In both cases the ovaries were moved well beyond the planned radiation field. We propose that open or laparoscopic ovarian repositioning in children is a simple, flexible, and reversible option to reduce radiation injury to the ovaries in pediatric cancer patients.

Rapid prototyping technique for creating a radiation shield.

Radiation therapy for the treatment of head and neck skin cancer poses challenges because of the inherently uneven tissue topography of the face and the need to protect surrounding unaffected tissues. The use of a customized radiation shield that combines tissue-equivalent bolus material with protective material addresses these issues. This article describes a technique using rapid prototyping to design and fabricate an extraoral radiation shield. This innovative application provides an expedient, standardized approach for delivering radiotherapy to the face, which is not only more comfortable for the patient, but allows more precise treatment delivery.

RT-PCR for PSA as a prognostic factor for patients with clinically localized prostate cancer treated with radiotherapy.

OBJECTIVES: To study prospectively the prognostic significance of the reverse transcriptase-polymerase chain reaction (RT-PCR) assay for patients with prostate cancer treated definitively with external beam radiotherapy. The RT-PCR assay for prostate-specific antigen (PSA) has been used to detect circulating prostate cancer cells in the serum of patients with prostate cancer. METHODS: In prospective fashion, serum RT-PCR testing was performed before and/or after definitive therapy, with the results scored as positive or negative. The results were analyzed for 161 patients, and the RT-PCR result was correlated with the treatment outcome. RESULTS: The median follow-up was 29 months. The pretreatment RT-PCR result was not predictive of biochemical relapse-free survival (bRFS) or clinical disease-free survival (DFS). Of 25 patients with T3-T4 tumors, those with a negative pretreatment RT-PCR result had better bRFS and a trend was noted toward better DFS compared with those with a positive result. Among patients with Gleason score 8 to 10 tumor who underwent pretreatment testing (n = 19), those with a negative RT-PCR result had better bRFS and DFS compared with those with a positive result. A trend toward better bRFS was seen for patients with negative versus positive post-treatment RT-PCR results. The DFS was better for patients with negative versus positive post-treatment RT-PCR results. CONCLUSIONS: RT-PCR, when obtained before radiotherapy, may be predictive of outcome for patients with more advanced stages or higher Gleason scores. Post-treatment testing predicted for clinical relapse. Additional study is needed before RT-PCR is used regularly in clinical practice.