Practical Radiation Oncology最新文献

Background: Bevacizumab has been demonstrated to have superior efficacy in the treatment of cerebral radiation necrosis (CRN), but its high cost may exacerbate the disease burden. This study aimed to assess the cost-effectiveness of bevacizumab in comparison to corticosteroids for treating CRN from the US payers' perspective.

Methods: Decision tree models were constructed to simulate the process of bevacizumab and corticosteroids in CRN short-term and long-term therapy. Critical clinical data were derived from the NCT01621880 trial. Costs and utility values were obtained from the US official websites and published literature. The main outcomes were total costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratio (ICER). One-way and probabilistic sensitivity analyses were performed to assess the robustness of the models.

Results: In the short-term and long-term models, bevacizumab added 0.11 (0.46 vs 0.35) and 0.16 (0.54 vs 0.38) QALYs compared with corticosteroids therapy, with corresponding incremental costs of $12,351 and $23,253, respectively. The resultant ICERs were $112,987/QALY and $150,245/QALY for short-term and long-term treatment, respectively. The one-way sensitivity analysis indicated that utility value of nonrecurrence status, body weight, and bevacizumab price per cycle were the most influential factors for ICER of both models. At the willingness-to-pay threshold of $150,000/QALY in the United States, the probabilities of bevacizumab being cost-effective for CRN short and long-term treatment were 63.9% and 49%, respectively.

Conclusions: Compared with corticosteroids, bevacizumab is an economical alternative for CRN short-term treatment from the US payers' perspective, whereas long-term therapy draws an opposite conclusion.

Vulvar cancer, though rare, poses significant challenges in diagnosis and treatment due to its histopathological complexities and nuances. This paper reviews key aspects of the management of vulvar cancer, focusing on histopathological diagnosis, margin status interpretation, lymph node involvement assessment, and ongoing clinical trials.

In oncology, "survival curves" frequently appear in journal articles and meeting presentations. The most common labels on survival curves are overall survival, relapse-free survival, progression-free survival, distant metastasis-free survival, and local and/or regional control. Unfortunately, consistency in the definition of an event differs between authors for the same prescribed survival analyses. Furthermore, the quality of survival curves can be greatly impacted by the methodology used for endpoint selection. This paper will briefly explain widely used names and event endpoints for survival analyses in a way that will help radiation oncologists consistently present and interpret experimental findings that influence clinical practice decisions.

Oropharyngeal cancer (OphC) is extremely rare during pregnancy, although its incidence is expected to increase in the years to come. Any delay in treatment can heavily affect cancer control and survival. Information regarding radiation therapy during pregnancy and long-term pediatric outcomes is lacking. In this article, we discuss a case of OphC in a pregnant woman, treated with surgery and radiation therapy, offering also an updated review with respect to the limited current evidence of the feasibility and clinical results of radiation therapy during pregnancy. A 39-year-old pregnant woman (through assisted fertilization) with locally advanced OphC underwent surgery and subsequent radiation therapy. A special fetal shielding device and a modified planning optimization strategy were used to reduce the dose to the fetus as much as possible. Phantom and in vivo dosimetry were performed to estimate the dose to the fetus and the related risks, according to International Commission on Radiological Protection (ICRP) publication 90. Thanks to the actions taken, the mean dose to the fetus was estimated to be around 50 mSv. A healthy baby was born at 33 weeks of gestation + 6 days. After a 10-year follow-up, the patient is in complete remission, and her 16-year-old daughter is healthy with good school performance. Adjuvant radiation therapy in OphC during pregnancy may be optimized to reduce the dose to the fetus, and the measures taken represent a realistic option to ensure the mother and baby's health.

Purpose: To generate a map of local recurrences after neoadjuvant chemotherapy and radiation (total neoadjuvant therapy or TNT) followed by surgical resection for pancreatic ductal adenocarcinoma (PDAC). Such recurrence patterns will serve to inform radiation treatment planning volumes that should be given in the neoadjuvant setting.

Methods: Locoregional recurrences following TNT followed by surgery treated between 2009-2022 were radiologically identified. Recurrences were individually segmented using MIM software and complied in a single base scan. All contour compilations were used to create a threshold contour encompassing 80% of recurrences among all patients, head only, and body/tail only. The distance between organs at risk and the threshold contour were measured to design an optimal clinical target volume (CTV) contour for patients treated with TNT. Recurrence patterns were also compared to existing adjuvant guidelines to assess coverage.

Results: A database of 484 patients managed with TNT for PDAC was queried. While locoregional recurrences were rare in this cohort, we identified eighty patients with either isolated locoregional or simultaneous local and distant recurrences. Patients with diagnostic imaging at the time of recurrence were identified. The majority of recurrences were partially in the field of published contouring guidelines or volumetric expansions off of vessels, and volumetric coverage was low for all. Common areas of recurrence include the aortico-diaphragmatic junction, retro-pancreatic duodenal nodal basin, and the region to the right of the superior mesenteric artery. A novel set of proposed neoadjuvant contours was designed to cover the central-most 80% of recurrences.

Conclusions: This is the largest collection of local/regional PDAC recurrences from a cohort of patients treated exclusively with TNT. Patterns of local/regional recurrence using TNT in PDAC vary significantly from those patients with PDAC treated with a surgery-first approach. Novel contouring guidelines presented herein can help to ensure optimal coverage of high risk regions and avoid reliance on the current adjuvant guidelines to guide treatment planning.

Purpose: This study quantifies intrafraction motion in surface-guided radiation therapy (SGRT) for breast cancer and considers the need for individualized intrafraction motion measures when calculating planning target volume (PTV) margins.

Methods and materials: SGRT was used to assess intrafraction motion in consecutive patients according to (1) site irradiated (whole-breast/chest wall vs whole-breast/chest wall + regional lymph nodes) and (2) the use of deep inspiration breath hold versus free breathing. Intrafraction motion variation was evaluated throughout the treatment course for all cases. Associations between intrafraction motion and patient-specific characteristics were explored. The usefulness of individualized intrafraction motion measures for PTV margin determination was considered.

Results: One hundred two patients undergoing 1360 fractions were included. On a population level, average intrafraction motion was less than 0.4 mm and 0.2 degrees for translational and rotational directions, respectively, with 95th percentiles <1.2 mm and 0.6 degrees, respectively. No clinically meaningful differences in intrafraction motion were observed according to the site irradiated or the use of deep inspiration breath hold. Consistency in intrafraction motion was noted for all patients throughout the treatment course. No clinically meaningful associations were found between intrafraction motion and patient-specific characteristics such as age, seroma volume, PTV volume, and mean body volume.

Conclusions: Intrafractional deviations with SGRT, using manufacturer-recommended regions of interest, are minimal, do not vary substantially for different treatment techniques or patient-specific characteristics, and remain constant throughout the treatment course. A universal intrafraction motion measure may be sufficient for calculating PTV margins. Further validation studies are needed to evaluate the impact of region of interest size and coverage.

Continuous glucose monitors (CGMs) are an increasingly prevalent electronic medical device used by patients with diabetes, offering several advantages over "finger sticks." There is a resulting rise in patients with CGMs seen in radiation oncology clinics. Manufacturers specify that CGMs should not be exposed to radiation (both diagnostic and therapeutic) due to the risk of device damage, creating challenges for patients and providers. We present a workflow for the management of CGMs in radiation oncology patients, beginning with systematic screening by providers and staff. We propose options for CGM management together with the device prescriber, including removal of the CGM or keeping it in place with periodic finger sticks to confirm the accuracy and offer guidance to radiation oncology providers and staff.

Purpose: To evaluate the outcome of partial breast reirradiation (re-PBI) with intensity modulated radiation therapy using a hypofractionated scheme for breast cancer (BC) local relapse (LR) operated on with repeat breast-conservative surgery.

Methods and materials: Intensity modulated radiation therapy-based re-PBI was performed using either helical or step-and-shoot modality to deliver 37.05 Gy in 13 fractions in 2.5 weeks. Cumulative incidence of second LR, toxicity, disease-free survival (DFS), BC-specific survival, and overall survival were evaluated.

Results: Between May 2012 and May 2021, 70 patients had re-PBI. The median follow-up (FU) was 6.3 years (quartiles 1-3, 4.0-8.1.). The median age at first LR was 62 years. The median primary BC first LR interval was 12.4 years (range, 1.6-26.7 years). Luminal A-like first LR accounted for 41% of the cases, and the median size was 0.8 cm. During FU, 18 (26%) patients showed a subsequent event: 3 second LRs (corresponding to an 8-year cumulative rate of 4%), 3 regional nodal recurrences, 7 distant metastases, and 5 other primary tumors. At 8 years, DFS, BC-specific survival, and overall survival were 76%, 90%, and 90%, respectively. At multivariate analysis, grade 3 and extensive intraductal components were independent predictors for DFS. For 51 and 46 patients, chronic toxicity and cosmesis were evaluated, respectively: 4% had grade 3 fibrosis, and cosmesis was deemed good/excellent in just >60% of the cases.

Conclusions: Re-PBI after repeat breast-conservative surgery represents a feasible alternative to mastectomy with regard to local control, showing an acceptable toxicity profile. A long-term FU is crucial to better understand the pattern of relapse and consolidate the position of re-PBI in clinical practice.