Analysis of multicatheter interstitial brachytherapy: Accelerated partial breast irradiation in a retrospective cohort of early-stage breast cancer patients.

PURPOSE: To determine cardiac dose received by patients treated with high dose rate interstitial brachytherapy. Patients with early-stage, node negative breast cancer can be treated using multi-catheter interstitial brachytherapy accelerated partial breast irradiation (MIB-APBI), with the benefit of reduced treatment volumes and favorable toxicity. METHODS AND MATERIALS: We conducted a retrospective review of left-sided breast cancer patients treated using MIB-APBI at our institution since 2014. The mean heart dose (MHD) was calculated using the Oncentra 3.2 planning system. The minimum distance between the planning target volume (PTVeval) and heart contour was measured manually. FINDINGS: 81 patients were included. The upper outer quadrant was the most common site. The MHD was 97.8 cGy (EQD2a/b=2) (range 22-229 cGy). MHD significantly correlated with the closest distance between PTVeval and heart contour (correlation coefficient -0.823, p <0.001); size of PTVeval (cc) and quadrant location did not. CONCLUSIONS: Appropriately selected women with early-stage, low-risk, left-sided breast cancer who received MIB-APBI had acceptable MHD. There was a strong correlation between the distance of PTVeval and MHD. Quadrant breast tumor is in cannot be used as a surrogate for MHD in brachytherapy. Our findings contribute to the growing evidence of the utility and safety of MIB-APBI.

A Precise Approach for Radiotherapy of Breast Cancer.

Radiotherapy is an integral part of the multidisciplinary management of breast cancer (BC). There have been multiple recent advances in the delivery of radiotherapy, reviewed with a critical discussion of the evidence from trials investigating adjuvant ultra-hypofractionation and partial breast irradiation for early-stage BC, and the locoregional management of lymph nodes in locally advanced BC. Multiple precision medicine-based approaches have been developed as prognostic and/or predictive for BC patients and identifying biomarkers of radioresistance could help identify patients that may benefit from dose-escalated radiotherapy or radiosensitizers. Radiotherapy after breast reconstruction is an area of current controversy in the field, and we evaluated the decision-making considerations in this situation. The oligometastatic state is an emerging field for many cancer sites based on recent trials investigating ablative radiotherapy for oligometastatic BC. This chapter is an overview of radiotherapy for BC, with a focus on recent advances in early-stage, locally advanced, and oligometastatic disease.

Stereotactic body radiotherapy to treat breast cancer oligometastases: A systematic review with meta-analysis.

OBJECTIVES: Stereotactic ablative radiotherapy (SABR) has been reported to be an effective treatment for oligometastatic disease from different primary cancer sites. Here we assess the effectiveness and safety of SABR for oligometastatic breast cancer patients by performing a meta-analysis. METHODS: Following PRISMA and MOOSE guidelines, a systematic review and meta-analysis was performed. Eligible studies were identified on Medline, Embase, Cochrane Library, and annual meetings proceedings from 1990 to June 2021. A meta-regression analysis was performed to assess if there was a correlation between moderator variables and outcomes, and a p-value <0.05 was considered significant. RESULTS: Ten studies met criteria for inclusion, comprising 467 patients and 653 treated metastases. The 1- and 2-year local control rates were 97% (95% CI 95-99%), and 90% (95% CI 84-94%), respectively. Overall survival (OS) was 93% (95% CI 89-96%) at 1 year, 81% (95% CI 72-88%) at 2 years. The rate of any grade 2 or 3 toxicity was 4.1 % (95% CI 0.1-5%), and 0.7% (0-1%), respectively. In the meta-regression analysis, only prospective design (p = 0.001) and bone-only metastases (p = 0.01) were significantly associated with better OS. In the subgroup analysis, the OS at 2y were significantly different comparing HER2+, HR+/HER2(-) and triple negative breast cancer 100%, 86% and 32%, p = 0.001. For local control outcomes, hormone receptor status (p = 0.01) was significantly associated on meta-regression analysis. CONCLUSION: SABR for oligometastatic breast cancer is safe and associated with high rates of local control. Longer follow-up of existing data and ongoing prospective trials will help further define the role of this management strategy.

Electromagnetic (EM) catheter path tracking in ultrasound-guided brachytherapy of the breast.

PURPOSE: To evaluate a novel navigation system for breast brachytherapy, based on ultrasound (US)-guided catheter needle implantations followed by electromagnetic (EM) tracking of catheter paths. METHODS: Breast phantoms were produced, containing US-visible tumors. Ultrasound was used to localize the tumor pose and volume within the phantom, followed by planning an optimal catheter pattern through the tumor using navigation software. An electromagnetic (EM)-tracked catheter needle was used to insert the catheters in the desired pattern. The inserted catheters were visualized on a post-implant CT, serving as ground truth. Electromagnetic (EM) tracking and reconstruction of the inserted catheter paths were performed by pulling a flexible EM guidewire through each catheter, performed in two clinical brachytherapy suites. The accuracy of EM catheter tracking was evaluated by calculating the Hausdorff distance between the EM-tracked and CT-based catheter paths. The accuracy and clinical feasibility of EM catheter tracking were also evaluated in three breast cancer patients, performed in a separate experiment room. RESULTS: A total of 71 catheter needles were implanted into 12 phantoms using US guidance and EM navigation, in an average ± SD time of 8.1 ± 2.9 min. The accuracy of EM catheter tracking was dependent on the brachytherapy suite: 2.0 ± 1.2 mm in suite 1 and 0.6 ± 0.2 mm in suite 2. EM catheter tracking was successfully performed in three breast brachytherapy patients. Catheter tracking typically took less than 5 min and had an average accuracy of 1.7 ± 0.3 mm. CONCLUSION: Our preliminary results show a potential role for US guidance and EM needle navigation for implantation of catheters for breast brachytherapy. EM catheter tracking can accurately assess the implant geometry in breast brachytherapy patients. This methodology has the potential to evaluate catheter positions directly after the implantation and during the several fractions of the treatment.

Contemporary role of radiotherapy in the management of penile cancer.

Penile cancer is a rare clinical entity that contributes to significant patient morbidity and mortality. Human papilloma virus (HPV) plays an important role in the carcinogenesis of penile squamous cell carcinoma (SCC), is associated with improved clinical outcomes, and is predictive for response to treatment with chemotherapy and radiotherapy. Historically, treatment consisted of radical surgery with partial or total penectomy. While effective for local control, surgical resection can impart significant physical, psychological and sexual dysfunction for afflicted men. Organ preservation strategies offer significant quality of life advantages over standard surgery and can be utilized without compromising oncological control. As an alternative or adjunct to surgical resection, radiation therapy can be used for organ preservation strategies successfully in up to 70% of patients. A variety of treatment techniques can be employed depending on the location and burden of disease. Limited disease can be amenable to treatment with interstitial brachytherapy, surface mold plesiotherapy or external beam radiotherapy. For locally advanced presentations, or for patients not amenable to surgical resection, excellent clinical outcomes can be achieved using a combination of chemotherapy and radiation therapy. Here, we discuss the management of penile SCC using modern radiation therapy treatment techniques, the expected clinical outcomes for organ preservation, as well as the management of side-effects and toxicities. While large randomized trials are being developed, the management of penile cancer is informed from the management of other of other anogenital malignancies, which we also review.

Issues in Managing Hurthle Cell Carcinoma of Thyroid: A Case Report.

A 61-year-old woman noticed a right neck lump in October 2001. Fine needle aspiration showed follicular neoplasm, adenoma versus carcinoma. The ultrasound scan showed a solid mass of maximum dimension of 3.7 cm. She had a right thyroid lobectomy and isthmectomy in January 2002 (first surgery). The tissue specimen showed a 4.5 cm Hurthle cell carcinoma (HCC) with vascular invasion. There were no capsular invasion, extra-thyroidal extension, or margin involvement. A completion left lobectomy (second surgery) was performed two weeks later. Therefore the pathological stage is II (T3N0M0). She received adjuvant radioactive iodine ablation for residual thyroid tissue. By 2003, she developed local recurrence, which was resected (third surgery), followed by adjuvant external beam radiotherapy. Unfortunately, she developed further recurrence in the left main bronchus, as identified by Indium-111 Octreotide (Curium, Missouri, USA) and positron emission tomography-computed tomography PET-CT imaging in 2006. She underwent a left pneumonectomy (fourth surgery) in July 2006. In November 2007 she was found to have mediastinal recurrence which was treated with high-dose external beam radiotherapy. She initially responded but developed more local recurrence and a lung metastasis by 2011. She was treated with brivanib with ixabepilone, under a phase I clinical trial with mixed response. Her treatment was discontinued secondary to toxicity and she succumbed to her disease in 2012. This case report illustrates the natural history and clinical decision making for patients diagnosed with HCC of the thyroid. Specifically, we highlight the clinical issues surrounding the histopathological diagnosis, extent of surgical resection, radioiodine diagnostic imaging/ablative treatment, as well as external beam radiotherapy.

Piloting prostate cancer patient-reported outcomesin clinical practice.

PURPOSE: The expanded prostate cancer index composite-26 (EPIC-26) instrument is a validated research tool used for capturing patient-reported quality-of-life outcomes related to the domains of bowel, bladder, and sexual functioning for men undergoing curative treatment for prostate cancer. The purpose of this pilot study was to explore the perceptions and experiences of clinicians with using EPIC-26 in a clinical setting for patients receiving curative radiotherapy. METHODS: Ten clinicians reviewed EPIC-26 scores either before or during weekly clinical encounters with patients receiving curative radiation treatment for prostate cancer. After a period of 2 months, clinicians underwent individual semi-structured interviews where they were asked about their views on measuring patient-reported outcomes in practice, the value of EPIC-26, impressions on patient acceptability, and operational issues. RESULTS: There was a general willingness and acceptance by clinicians to use EPIC-26 for routine clinical practice. Clinician participants found EPIC-26 to be generally informative, and added value to the clinical encounter by providing additional information that was specific to prostate cancer patients. EPIC-26 was also felt to improve overall communication and provide additional insight into the patient experience. CONCLUSIONS: Our qualitative findings suggest that there may be a role for incorporating patient-reported outcome measure assessment tools like EPIC-26 routinely into clinical practice. However, further qualitative and quantitative research is required in order to assess the impact of patient-reported outcome information on communication, patient and clinician satisfaction, and how these and other related outcomes can be used for guiding treatment decision-making.