Flattening Filter-Free Volumetric-Modulated Arc Radiotherapy for Left-Sided Whole-Breast, Partial-Breast, and Postmastectomy Irradiations.

Purpose: Unflattened photon beams exhibit many benefits over traditional flattened beams for radiotherapy (RT), but comprehensive evaluations of dosimetric results and beam-on time using flattening filter-free (FFF) beams for all types of breast irradiations are still lacking. The purpose of this study was to investigate if FFF RT can maintain equal or better dose coverage than standard flattened-beam RT while reducing doses to organs at risk (OARs) and beam-on time for various types of breast cancer irradiations. Methods and Materials: FFF volumetric-modulated arc therapy (FFF-VMAT) and standard VMAT (STD-VMAT) treatment plans were created for 15 whole-breast irradiation (WBI) patients with 50 Gy/25 fractions, 13 partial-breast irradiation (PBI) patients with 38.5 Gy/10 fractions, and 9 postmastectomy irradiation (PMI) patients with 50 Gy/25 fractions. Planning target volume (PTV) coverage and dose to OARs were evaluated. Results: Both techniques produced clinically acceptable plans for all three types of irradiations. For WBI, FFF-VMAT plans exhibited similar PTV and OARs evaluation metrics as STD-VMAT. For PBI, FFF-VMAT plans showed significantly lower mean and maximum doses for ipsilateral and contralateral lungs, contralateral breast, and heart. For PMI, FFF-VMAT plans showed significantly lower mean dose and V5 for contralateral breast but significantly higher Dmean, Dmax, and V20 for ipsilateral lung and significantly higher Dmean, V22.5, and V30 for heart. FFF-VMAT techniques significantly reduced beam-on time than STD-VMAT for all cases. Conclusion: This work has shown that FFF beams are most beneficial for small-field irradiation such as PBI, and breast cancer patients could potentially benefit from the shortened beam-on time.

Comparison of conventional and advanced radiotherapy techniques for left-sided breast cancer after breast conserving surgery.

Whole breast radiotherapy (WBRT) after breast conserving surgery is the standard treatment to prevent recurrence and metastasis of early stage breast cancer. This study aims to compare seven WBRT techniques including conventional tangential, field-in-field (FIF), hybrid intensity-modulated radiotherapy (IMRT), IMRT, standard volumetric modulated arc therapy (STD-VMAT), noncoplanar VMAT (NC-VMAT), and multiple arc VMAT (MA-VMAT). Fifteen patients who were previously diagnosed with left-sided early stage breast cancer and treated in our clinic were selected for this study. WBRT plans were created for these patients and were evaluated based on target coverage and normal tissue toxicities. All techniques produced clinically acceptable WBRT plans. STD-VMAT delivered the lowest mean dose (1.1 ± 0.3 Gy) and the lowest maximum dose (7.3 ± 4.9 Gy) to contralateral breast, and the second lowest lifetime attributable risk (LAR) (4.1 ± 1.4%) of secondary contralateral breast cancer. MA-VMAT delivered the lowest mean dose to lungs (4.9 ± 0.9 Gy) and heart (5.5 ± 1.2 Gy), exhibited the lowest LAR (1.7 ± 0.3%) of secondary lung cancer, normal tissue complication probability (NTCP) (1.2 ± 0.2%) of pneumonitis, risk of coronary events (RCE) (10.3 ± 2.7%), and LAR (3.9 ± 1.3%) of secondary contralateral breast cancer. NC-VMAT plans provided the most conformal target coverage, the lowest maximum lung dose (46.2 ± 4.1 Gy) and heart dose (41.1 ± 5.4 Gy), and the second lowest LAR (1.8 ± 0.4%) of secondary lung cancer and RCE (10.5 ± 2.8%). MA-VMAT and NC-VMAT could be the preferred techniques for early stage breast cancer patients after breast conserving surgery.

Postmastectomy radiotherapy for left-sided breast cancer patients: Comparison of advanced techniques.

Postmastectomy radiotherapy (PMRT) has been shown to improve the overall survival for invasive breast cancer patients, and many advanced radiotherapy technologies were adopted for PMRT. The purpose of our study is to compare various advanced PMRT techniques including fixed-beam intensity-modulated radiotherapy (IMRT), non-coplanar volumetric modulated arc therapy (NC-VMAT), multiple arc VMAT (MA-VMAT), and tomotherapy (TOMO). Results of standard VMAT and mixed beam therapy that were published by our group previously were also included in the plan comparisons. Treatment plans were produced for nine PMRT patients previously treated in our clinic. The plans were evaluated based on planning target volume (PTV) coverage, dose homogeneity index (DHI), conformity index (CI), dose to organs at risk (OARs), normal tissue complication probability (NTCP) of pneumonitis, lifetime attributable risk (LAR) of second cancers, and risk of coronary events (RCE). All techniques produced clinically acceptable PMRT plans. Overall, fixed-beam IMRT delivered the lowest mean dose to contralateral breast (1.56 ± 0.4 Gy) and exhibited lowest LAR (0.6 ± 0.2%) of secondary contralateral breast cancer; NC-VMAT delivered the lowest mean dose to lungs (7.5 ± 0.8 Gy), exhibited lowest LAR (5.4 ± 2.8%) of secondary lung cancer and lowest NTCP (2.1 ± 0.4%) of pneumonitis; mixed beam therapy delivered the lowest mean dose to heart (7.1 ± 1.3 Gy) and exhibited lowest RCE (8.6 ± 7.1%); TOMO plans provided the most optimal target coverage while delivering higher dose to OARs than other techniques. Both NC-VMAT and MA-VMAT exhibited lower values of all OARs evaluation metrics compare to standard VMAT. Fixed-beam IMRT, NC-VMAT, and mixed beam therapy could be the optimal radiation technique for certain breast cancer patients after mastectomy.

A single-institution, randomized, pilot study evaluating the efficacy of gabapentin and methadone for patients undergoing chemoradiation for head and neck squamous cell cancer.

BACKGROUND: The objective of the current study was to compare the safety and efficacy between 2 analgesic regimens for patients with head and neck cancer (HNC) undergoing definitive chemoradiation (CRT). METHODS: The current study was a prospective, single-institution, 2-arm, randomized pilot study. Patients with American Joint Committee on Cancer seventh edition stage II to stage IV squamous cell carcinoma of the head and neck who were undergoing CRT were randomized to either arm 1, which entailed high-dose gabapentin (2700 mg daily) with the institutional standard of care (hydrocodone and/or acetaminophen progressing to fentanyl as needed), or arm 2, which comprised low-dose gabapentin (900 mg daily) with methadone. The primary endpoints were safety and toxicity. Secondary endpoints were pain, opioid requirement, and quality of life (QOL). Differences between the treatment arms at multiple time points were compared using a generalized linear mixed regression model with Sidak correction. RESULTS: A total of 60 patients (31 in arm 1 and 29 in arm 2) were enrolled from April 2015 to August 2017. There was no difference between the treatment arms with regard to adverse events or serious adverse events. Pain was not found to be different between the treatment arms. More patients in arm 1 did not require an opioid during treatment (42% vs 7%; P = .002). Patients in arm 2 experienced significantly better QOL outcomes across multiple domains, including overall health (P = .05), physical functioning (P = .04), role functioning (P = .01), and social functioning (P = .01). CONCLUSIONS: High-dose prophylactic gabapentin increased the percentage of patients who required no opioid during treatment. Methadone may improve QOL compared with a regimen of short-acting opioids and fentanyl. However, pain was found to significantly worsen throughout treatment regardless of treatment arm, necessitating further studies to identify a more optimal regimen.

Dosimetric comparison of deep-inspiration breath-hold and free-breathing treatment delivery techniques for left-sided breast cancer using 3D surface tracking.

INTRODUCTION: While radiation therapy has been shown to increase local control and overall survival for breast cancer, late cardiac toxicity remains a concern. Morbidity and mortality have been shown to increase proportionally to the mean heart dose. Deep inspiration breath-hold (DIBH) can reduce heart dose compared to free-breathing (FB) by increasing the heart-to-chest wall distance, especially in left-sided breast cancer. We present our clinical experience with DIBH in left breast and chest-wall irradiation using 3D optical surface tracking. MATERIALS & METHODS: 29 patients were treated with DIBH using a surface tracking system that provides a real time 3D surface image of the patient. Comparisons of maximum and mean heart dose, heart-chest wall separation, and the percentage of lung volume that receives 20 or more Gy (V20) between the DIBH and hypothetical FB treatment plans were conducted with the Student's t-test. Correlation coefficients were also calculated for heart-chest wall separation, heart volume, and lung volume. RESULTS: Comparing DIBH and FB plans showed a decrease in mean and maximum heart doses in all patients. Individual mean heart doses decreased by an average of 1.12 Gy, and the average mean heart dose for DIBH plans was significantly lower than corresponding FB plans (1.02 vs. 2.12 Gy; p < 0.0001). Maximum heart dose decreased by an average of 11.88 Gy and was significantly lower in DIBH versus FB plans (28.33 vs. 43.7 Gy; p = 0.0001). The average difference in heart to chest-wall separation between DIBH and FB images was 2.41 cm. DIBH left lung volume and measured increases in volume on inspiration inversely correlated with maximum heart dose (R = 0.39) and left lung V20 (R = 0.32). CONCLUSIONS: DIBH with 3D surface tracking can significantly benefit patients with left sided disease by limiting the mean and maximum heart dose. DIBH appears to viably reduce heart dose for left-breast cancer patients and thus potentially reduce long-term complications without prolonging treatment delivery.

Minimally invasive rib-sparing video-assisted thoracoscopic surgery resections with high-dose-rate intraoperative brachytherapy for selected chest wall tumors.

BACKGROUND: By avoiding chest wall resection, iridium-192 (Ir-192) high-dose-rate (HDR) intraoperative brachytherapy (IOBT) and video-assisted thoracoscopic surgery (VATS) might improve outcomes for high-risk patients requiring surgical resection for pulmonary malignancy with limited pleura and/or chest wall involvement. METHODS AND MATERIALS: Seven patients with non-small cell lung cancer involving the pleura or chest wall underwent VATS pulmonary resections combined with HDR IOBT. After tumor extraction, an Ir-192 source was delivered via a Freiburg applicator to intrathoracic sites with potential for R1-positive surgical margins. The number of catheters, dwell position along each catheter, prescription depth, and dose were customized based on clinical needs. RESULTS: Six patients had pT3N0M0 non-small cell lung cancers. A seventh case was a recurrent sarcomatoid carcinoma. One case required conversion to open thoracotomy for pneumonectomy with en bloc chest wall resection. There were no intraoperative complications and average operative time was 5.8 hours. Five of seven patients without transmural chest wall involvement underwent rib-sparing resection. Four of the 6 patients treated with VATS and IORT remain alive in follow-up without evidence of local recurrence (median follow-up, 25 months). Noted toxicities were recurrent postoperative pneumothorax, pleural effusion with persistent chest wall pain, avid fibrosis at 2 years of follow-up, and a late traumatic rib fracture. CONCLUSIONS: HDR IOBT with Ir-192 via VATS is technically feasible and safe for intrathoracic disease with pleural and/or limited chest wall involvement. Short-term morbidity associated with chest wall resection may be reduced. Additional study is required to define long-term benefits.

Single-fraction stereotactic body radiation therapy for sinonasal malignant melanoma.

BACKGROUND: A rare head and neck disease that may benefit from definitive or palliative stereotactic body radiation therapy (SBRT) is sinonasal malignant melanoma. These tumors can be very aggressive and often lead to severe epistaxis and significant mass effect. Results from only a handful of head and neck sinonasal malignant melanoma treated with SBRT are available in the current literature. METHODS: The following reports on 2 cases of sinonasal malignant melanoma that recurred postoperatively and were subsequently treated at Roswell Park with SBRT. Both were treated with a single fraction of 15 Gy. RESULTS: Nearly instant relief of their chronic epistaxis and complete responses were seen in both patients. One patient is alive and free of disease 7 years after radiation. CONCLUSION: These patients with sinonasal malignant melanoma achieved symptomatic relief of severe bleeding and airway issues from single-fraction SBRT. SBRT should be considered as a treatment option in patients with unresectable sinonasal malignant melanoma.

Radiation for bone metastases.

PURPOSE OF REVIEW: To synopsize the current state-of-the-art for radiation and treatment of painful bone metastases with a focus on prostate cancer. RECENT FINDINGS: Although external beam radiation has long been known to palliate painful bone metastatic disease for patients with prostate cancer, new studies continue to evolve in this area. Data from randomized studies over the past decade emphasize that palliation can be achieved with single-fraction radiation strategies. Despite these data, and various supportive national and international guidelines, single-fraction regimens are relatively underutilized in the USA as compared with other countries. In addition to external beam radiation, beta-emitting isotopes are also effective as systemic agents for the palliation of painful bone metastases. New alpha-emitters such as Alpharadin (radium-223) are under current development but remain unproven at this time and recent data indicate that this agent can prolong survival in patients with advanced prostate cancer. SUMMARY: Radiation in various forms is highly effective for palliation of pain associated with bone metastases.

Socially responsible medical education: innovations and challenges in a minority setting.

CONTEXT: Distributed medical education sites help train, recruit and retain doctors, notably in rural and isolated areas, by providing education and training in these areas and adapting their curriculum to meet the host community's health needs. OBJECTIVES: The Centre de Formation Médicale du Nouveau Brunswick (CFMNB; New Brunswick Medical Education Centre) was established by a partnership between two academic institutions, the Université de Sherbrooke (University of Sherbrooke), situated in the province of Quebec, and the Université de Moncton (University of Moncton), situated in the province of New Brunswick, in Canada. The CFMNB is specifically targeting a minority community (Acadians). Working to establish a high-quality medical education programme, the CFMNB has also set community objectives to meet not only the health needs of this population, but also its social and economic needs. METHODS: This paper describes the overall objectives of this project, which are: to reduce the gap between community needs and academic institutional needs; to address ethno-cultural and language differences in a defined minority population, and to develop collaboration between the partners involved, including government and community entities which are often perceived as operating in isolation from one another. We also describe why and how the CFMNB developed community-focused objectives and the challenges that came with these innovations, and present lessons from the experience that may be relevant to other sites interested in the social responsibility of medical schools. CONCLUSIONS: The CFMNB has produced interesting work and innovations in the field of social responsibility and has encountered many challenges. Continuing interaction between medical education, health research and health services to better address the needs of the population has been established. The information obtained by this process has been used to build a strategic plan for the CFMNB in order to ensure that it is socially responsive and has significant generalisable features.

18FDG PET in oncology: the best and the worst (Review).

The clinical added-value of 18F-fluoro-2-deoxy-D-glucose positron emission tomography (18FDG PET) in the management of oncology patients is increasingly documented. In the present review, we discuss both the benefits and the limitations of 18FDG PET in different cancers. Considering the literature data and our own experience, we also indicate the best clinical approach to optimize the use of metabolic imaging in oncology.