Accelerated partial breast irradiation: Current evidence and future developments.

Whole breast irradiation after breast-conserving surgery for early breast cancer has become one of the standard treatment modes for breast cancer and yields the same effect as radical surgery. Accelerated partial breast irradiation (APBI) as a substitute for whole breast irradiation for patients with early breast cancer is a hot spot in clinical research. APBI is characterised by simple high-dose local irradiation of the tumour bed in a short time, thus improving convenience for patients and saving costs. The implementation methods of APBI mainly include brachytherapy, external beam radiation therapy, and intraoperative radiotherapy. This review provides an overview of the clinical effects and adverse reactions of the main technologies of APBI and discusses the prospects for the future development of APBI.

Incidence, Characteristics and Survival Rates of Bladder Cancer after Rectosigmoid Cancer Radiation.

BACKGROUND: Historical external beam radiation therapy (EBRT) for rectosigmoid cancer (RCa) predisposed patients to an increased risk of secondary bladder cancer (BCa). However, no contemporary radiotherapy studies are available. We addressed this knowledge gap. MATERIALS AND METHODS: Within the Surveillance, Epidemiology, and End Results database (2000-2020), we identified non-metastatic RCa patients who either underwent radiotherapy (EBRT+) or did not (EBRT-). Cumulative incidence plots and multivariable competing risk regression models (CRR) were fitted to address rates of BCa after RCa. In the subgroup of BCa patients, the same methodology addressed BCa-specific mortality (BCSM) according to EBRT exposure status. RESULTS: Of the 188,658 non-metastatic RCa patients, 54,562 (29%) were EBRT+ vs. 134,096 (73%) who were EBRT-. In the cumulative incidence plots, the ten-year BCa rates were 0.7% in EBRT+ vs. 0.7% in EBRT- patients (p = 0.8). In the CRR, EBRT+ status was unrelated to BCa rates (multivariable HR: 1.1, p = 0.8). In the subgroup of 1416 patients with BCa after RCa, 443 (31%) were EBRT+ vs. 973 (69%) who were EBRT-. In the cumulative incidence plots, the ten-year BCSM rates were 10.6% in EBRT+ vs. 12.1% in EBRT- patients (p = 0.7). In the CRR, EBRT+ status was unrelated to subsequent BCSM rates (multivariable HR: 0.9, p = 0.9). CONCLUSION: Although historical EBRT for RCa predisposed patients to higher BCa rates, contemporary EBRT for RCa is not associated with increased subsequent BCa risk. Moreover, in patients with BCa after RCa, exposure to EBRT does not affect BCSM.

Fundamentals and recent advances in the evaluation and management of medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) is a rare primary neuroendocrine thyroid carcinoma that is distinct from other thyroid or neuroendocrine cancers. Most cases of MTC are sporadic, although MTC exhibits a high degree of heritability as part of the multiple endocrine neoplasia syndromes. REarranged during Transfection (RET) mutations are the primary oncogenic drivers and advances in molecular profiling have revealed that MTC is enriched in druggable alterations. Surgery at an early stage is the only chance for cure, but many patients present with or develop metastases. C-cell-specific calcitonin trajectory and structural doubling times are critical biomarkers to inform prognosis, extent of surgery, likelihood of residual disease, and need for additional therapy. Recent advances in the role of active surveillance, regionally directed therapies for localized disease, and systemic therapy with multi-kinase and RET-specific inhibitors for progressive/metastatic disease have significantly improved outcomes for patients with MTC.

Unexpected change in hydrogel spacer volume during external-beam radiation therapy.

PURPOSE: To reduce the rectal radiation dose during local radiation therapy of prostate cancer, a hydrogel spacer is typically implanted between the prostate and rectum. However, the spacer volume can change during external beam radiation therapy (EBRT). Therefore, we used magnetic resonance imaging (MRI) to determine changes in the spacer volume during EBRT and analyzed the data to identify patient factors influencing this change. MATERIALS AND METHODS: A hydrogel spacer was implanted in each enrolled patient diagnosed with prostate cancer (n = 22, age = 69-86 years) for EBRT with a total dose of 70 Gy over 35 fractions. T2-weighted MRI images were acquired before (median = 8 days) and during EBRT, when the radiation dose of 48 Gy (median) was given at 55 days (median) after implantation. MRI images were used to determine the spacer volume as well as the maximum and minimum distances between the prostate and anterior wall of the rectum at the middle height of the prostate. Scatterplots were created to determine whether correlations existed between changes in the spacer volume and these two distances, while uni- and multivariate analyses were conducted to determine if the spacer volume change was influenced by the following patient factors: age, body mass index, estimated glomerular filtration rate, and visceral fat areas at the umbilical and femoral head positions. RESULTS: The spacer volume increased in all 22 patients, with the smaller spacer volume before EBRT increasing by a larger amount during EBRT. This increase in the spacer volume was unaffected by other patient factors. However, it correlated with the change in the maximum distance between the prostate and anterior wall of the rectum. CONCLUSION: To avoid adverse changes in the rectal radiation dose during EBRT, hydrogel spacer volume should be monitored, especially if the pre-EBRT volume is small.

Revolutionizing Brain Tumor Care: Emerging Technologies and Strategies.

Glioblastoma multiforme (GBM) is one of the most aggressive forms of brain tumor, characterized by a daunting prognosis with a life expectancy hovering around 12-16 months. Despite a century of relentless research, only a select few drugs have received approval for brain tumor treatment, largely due to the formidable barrier posed by the blood-brain barrier. The current standard of care involves a multifaceted approach combining surgery, irradiation, and chemotherapy. However, recurrence often occurs within months despite these interventions. The formidable challenges of drug delivery to the brain and overcoming therapeutic resistance have become focal points in the treatment of brain tumors and are deemed essential to overcoming tumor recurrence. In recent years, a promising wave of advanced treatments has emerged, offering a glimpse of hope to overcome the limitations of existing therapies. This review aims to highlight cutting-edge technologies in the current and ongoing stages of development, providing patients with valuable insights to guide their choices in brain tumor treatment.

Short-course Radiotherapy for Airway Stenting in Malignant Airway Obstruction: A Case Report and Literature Review.

Background: Malignant airway obstruction (MAO) secondary to tumor growth occurs in nearly a third of patients with lung cancer and portends a very poor prognosis if untreated. Treatment options include bronchoscopic intervention with tumor debulking, stent placement, endobronchial brachytherapy, or palliative radiotherapy. Case Report: This is a report of a 74-year-old woman with a medical history of metastatic lung adenocarcinoma, hospitalized for dyspnea, hemoptysis, and chest pain with a radiographic finding of MAO on chest X-ray and computed tomography. Patient underwent radiation with a total dose of 13 Gy in two once-weekly fractions of 6.5 Gy per fraction. Three days after the end of radiation treatment, chest X-ray showed a completely right lung re-expansion without atelectasis. Two weeks after radiotherapy treatment, the patient was discharged from hospital without pulmonary symptoms. Conclusion: A different fractionation with a lower equivalent dose in 2 Gy fraction compared to literature data showed efficacy in resolving MAO with excellent local control in the first three months of follow-up.

TEAM participation in the irradiation of IROC phantoms for cooperative group clinical trials.

The participation of radiation oncology team members in the irradiation of Imaging and Radiation Oncology Core (IROC) phantom for cooperative group clinical trials is essential to comply with the latest quality management philosophy. Medical dosimetrists are expected to develop treatment plans for the irradiation of IROC phantoms. For advanced treatment techniques, such as three-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and volumetric-modulated arc therapy (VMAT), the irradiation of the IROC phantoms serves as quality audit. If successful, the irradiation processes demonstrate that the institution has the knowledge of the protocol, and has the appropriate equipment to comply with the protocol requirements. This article describes three IROC phantoms used for credentialing external beam photon beam therapy, delivered using conventional medical linear accelerators, to the medical dosimetry community. Guidance and strategies for the development of treatment plans are discussed. Our institutional irradiation of the three IROC phantoms, delivered using the Truebeam medical linear accelerator, resulted in consistent dose accuracy to within ±1%. The participation of the team members may reduce the overall published failing rate stated to be about one-third of all participating institutions.

Assessing the Efficacy and Long-Term Outcomes of Surgical Intervention Versus Radiotherapy: A Comprehensive Systematic Review and Meta-Analysis of Prostate Cancer Treatment Modalities.

There is controversy regarding the most effective primary treatment of choice for prostate cancer (PCa) in terms of patient outcomes, such as surgery or radiotherapy (RT). This study evaluated the comparative efficacy and long-term outcomes of radical prostatectomy (RP) and RT for PCa treatment. A thorough literature review of relevant databases was conducted, focusing on academic and clinical studies published from 2019 onwards. The inclusion criteria included randomized controlled trials (RCTs) and other observational studies comparing survival outcomes in patients treated with surgery and RT. We followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines to provide an overview of the data. We selected 19 studies based on the inclusion criteria. Of the total 19 studies, 12 advocated RP as the preferred treatment to improve survival outcomes in patients with PCa. The results of our synthesis showed that prostate cancer-specific mortality (PCSM) was lower in patients treated with RT. The total effect size for the analysis was calculated as Z=1.19 (p-value=0.23). The heterogeneity in the studies was as follows: Tau2=0.09, Chi2=20.25, df=4, I2=80%. Moreover, overall survival (OS) was shown to be higher in patients who underwent prostatectomy. The combined effect for the analysis was found to be: HR=0.97 (0.93, 1.01). The total effect was calculated as Z=1.33 (p-value= 0.18). The heterogeneity was found to be Tau2=0.00, Chi2=1.33, df=2, and I2=0%. However, overall mortality (OM) was shown to be independent of the treatment modality. RT is the preferred strategy for PCa treatment, as it balances efficacy and long-term outcomes. Clinical decision-making should consider individual patient characteristics and future research should delve into specific subpopulations and long-term outcomes to further refine the treatment guidelines.

Gross Tumor and Intracranial Control Benefits with Fractionated Radiotherapy Compared with Stereotactic Radiosurgery for Patients with WHO Grade 2 Meningioma.

OBJECTIVE: Surgical resection is the mainstay of treatment for WHO grade 2 meningioma. Fractionated radiation therapy (RT) is frequently used after surgery, though many centers utilize stereotactic radiosurgery (SRS) for recurrence or progression. Herein, we report disease control outcomes from an institutional cohort with adjuvant fractionated RT versus salvage SRS. METHODS: We identified 32 patients from an institutional database with WHO grade 2 meningioma and residual/recurrent tumor treated with either SRS or fractionated RT. Patients were treated between 2007 and 2021 and had at least 1 year of follow-up. Kaplan-Meier estimators were used to determine gross tumor control (GTC) and intracranial control (IC). Univariate Cox proportional hazards models using biologically effective dose (BED) as a continuous parameter were used to assess for dose responses. RESULTS: With a median follow-up of 5.5 years, 13 patients (41%) received SRS to a recurrent or progressive nodule, 2 (6%) fractionated RT to a recurrent or progressive nodule, and 17 (53%) adjuvant fractionated RT following subtotal resection. Five-year GTC was higher with fractionated RT versus SRS (82% vs. 38%, P = 0.03). Five-year IC was also better with fractionated RT versus SRS (82% vs. 11%, P < 0.001). On univariate analysis, increasing BED10 was significantly associated with better GTC (P = 0.039); increasing BED3 was not (P = 0.82). CONCLUSIONS: In this patient cohort, GTC and IC were significantly higher in patients treated with adjuvant fractionated RT compared with salvage SRS. Increasing BED10 was associated with better GTC. Fractionated RT may provide a better therapeutic ratio than SRS for grade 2 meningiomas.

Differences in real-world outcomes by risk classification for localized prostate cancer patients after radiation therapy.

BACKGROUND: Limited real-world evidence exists on the long-term clinical outcomes of patients with localized prostate cancer (LPC) who received external beam radiation therapy (EBRT) as the initial treatment. This study evaluated clinical outcomes of US patients with high-risk LPC (HR-LPC) and low/intermediate-risk LPC (LIR-LPC) who received EBRT. METHODS: This retrospective study using Surveillance, Epidemiology, and End Results-Medicare linked data from 2012 to 2019 included patients ≥ 65 years old who received EBRT as initial therapy. Baseline patient characteristics were summarized, metastasis-free survival (MFS), overall survival, and time to initiation of advanced prostate cancer treatment were compared using Kaplan-Meier (KM) and adjusted Cox proportional hazard (PH) models. 5-year survival probabilities stratified by race/ethnicity (non-Hispanic [NH] White, NH Black, NH Asian, and Hispanic) were assessed. RESULTS: Of 11,313 eligible patients, 41% (n = 4600) had HR-LPC and 59% (n = 6713) had LIR-LPC. Patient characteristics for both groups were comparable, with mean age at EBRT initiation > 70 years, 86% white, and mean follow-up time >40 months. More patients in the HR-LPC than LIR-LPC groups (78% vs 34%) had concurrent androgen deprivation therapy use and for a longer duration (median 10.4 months vs. 7.4 months). A higher proportion of HR-LPC patients developed metastasis, died, or received advanced prostate cancer treatment. Adjusted Cox PH survival analyses showed significantly (p < 0.0001) higher risk of mortality (hazard ratios [HR], 1.57 [1.38, 2.34]), metastasis or death (HR, 1.97 [1.78, 2.17]), and advanced prostate cancer therapy use (HR, 2.57 [2.11, 3.14]) for HR-LPC than LIR-LPC patients. Within 5 years after the initial EBRT treatment, 18%-26% of patients with HR-LPC are expected to have died or developed metastasis. The 5-year MFS rate in the HR-LPC group was lower than the LIR-LPC group across all racial/ethnic subgroups. NH Black patients with HR-LPC had the highest all-cause mortality rate and lowest rate of receiving advanced prostate cancer treatment, compared to other racial/ethnic subgroups. CONCLUSIONS: This real-world study of clinical outcomes in patients with LPC treated with EBRT suggests substantial disease burden in patients with HR-LPC and highlights the need for additional treatment strategies to improve clinical outcomes in patients with HR-LPC.

Process failure mode and effects analysis for external beam radiotherapy: Introducing a literature-based template and a novel action priority.

PURPOSE: The first aim of the study was to create a general template for analyzing potential failures in external beam radiotherapy, EBRT, using the process failure mode and effects analysis (PFMEA). The second aim was to modify the action priority (AP), a novel prioritization method originally introduced by the Automotive Industry Action Group (AIAG), to work with different severity, occurrence, and detection rating systems used in radiation oncology. METHODS AND MATERIALS: The AIAG PFMEA approach was employed in combination with an extensive literature survey to develop the EBRT-PFMEA template. Subsets of high-risk failure modes found through the literature survey were added to the template where applicable. Our modified AP for radiation oncology (RO AP) was defined using a weighted sum of severity, occurrence, and detectability. Then, Monte Carlo simulations were conducted to compare the original AIAG AP, the RO AP, and the risk priority number (RPN). The results of the simulations were used to determine the number of additional corrective actions per failure mode and to parametrize the RO AP to our department's rating system. RESULTS: An EBRT-PFMEA template comprising 75 high-risk failure modes could be compiled. The AIAG AP required 1.7 additional corrective actions per failure mode, while the RO AP ranged from 1.3 to 3.5, and the RPN required 3.6. The RO AP could be parametrized so that it suited our rating system and evaluated severity, occurrence, and detection ratings equally to the AIAG AP. CONCLUSIONS: An adjustable EBRT-PFMEA template is provided which can be used as a practical starting point for creating institution-specific templates. Moreover, the RO AP introduces transparent action levels that can be adapted to any rating system.

Unraveling the efficacy network: A network meta-analysis of adjuvant external beam radiation therapy methods after hepatectomy.

BACKGROUND: Primary liver cancer is a malignant tumor with a high recurrence rate that significantly affects patient prognosis. Postoperative adjuvant external radiation therapy (RT) has been shown to effectively prevent recurrence after liver cancer resection. However, there are multiple RT techniques available, and the differential effects of these techniques in preventing postoperative liver cancer recurrence require further investigation. AIM: To assess the advantages and disadvantages of various adjuvant external RT methods after liver resection based on overall survival (OS) and disease-free survival (DFS) and to determine the optimal strategy. METHODS: This study involved network meta-analyses and followed the PRISMA guidelines. The data of qualified studies published before July 10, 2023, were collected from PubMed, Embase, the Web of Science, and the Cochrane Library. We included relevant studies on postoperative external beam RT after liver resection that had OS and DFS as the primary endpoints. The magnitudes of the effects were determined using risk ratios with 95% confidential intervals. The results were analyzed using R software and STATA software. RESULTS: A total of 12 studies, including 1265 patients with hepatocellular carcinoma (HCC) after liver resection, were included in this study. There was no significant heterogeneity in the direct paired comparisons, and there were no significant differences in the inclusion or exclusion criteria, intervention measures, or outcome indicators, meeting the assumptions of heterogeneity and transitivity. OS analysis revealed that patients who underwent stereotactic body radiotherapy (SBRT) after resection had longer OS than those who underwent intensity modulated radiotherapy (IMRT) or 3-dimensional conformal RT (3D-CRT). DFS analysis revealed that patients who underwent 3D-CRT after resection had the longest DFS. Patients who underwent IMRT after resection had longer OS than those who underwent 3D-CRT and longer DFS than those who underwent SBRT. CONCLUSION: HCC patients who undergo liver cancer resection must consider distinct advantages and disadvantages when choosing between SBRT and 3D-CRT. IMRT, a RT technique that is associated with longer OS than 3D-CRT and longer DFS than SBRT, may be a preferred option.

Secondary bladder and colorectal cancer after treatments for prostate cancer: A population based study.

BACKGROUND: Prostate cancer (PCa) patients receiving radiotherapy may be predisposed to secondary malignancies. This study aimed to determine the association between PCa treatments, including radical prostatectomy (RP), external beam radiation therapy (EBRT), brachytherapy (BT) and androgen deprivation therapy (ADT); and secondary bladder and colorectal cancer. METHODS: A cohort study was constructed using Quebec administrative databases (Med-Echo and RAMQ). Included men were diagnosed and treated for PCa between 2000 and 2016. Patients with bladder or colorectal cancer prior to PCa were excluded. Follow-up ended at the earliest of the following: incidence of bladder or colorectal cancer, death, or December 31, 2016. EBRT, BT, EBRT+ADT, RP + ADT or ADT only were compared individually to RP. The incidence of secondary bladder and colorectal cancer were computed. Inverse probability of treatment weighting (IPTW) based on a propensity score was used to control for potential confounding. IPTW-Cox proportional hazards models were used. RESULTS: A significant association was found between secondary bladder cancer and EBRT (HR: 1.84, 95%CI: 1.60;2.13), and also EBRT+ADT (HR: 2.08, 95%CI: 1.67;2.56), but not with BT (HR: 1.36, 95%CI: 0.68;2.74). Secondary colorectal cancer was significantly associated to either EBRT (HR: 1.36, 95%CI: 1.21;1.53); or BT (HR: 2.46, 95%CI: 1.71;3.54). The association between ADT alone and both secondary cancers was also significant (HR: 1.98, 95%CI: 1.69;2.31 and HR: 1.69, 95%CI: 1.49;1.92, respectively). CONCLUSIONS: Compared to PCa patients undergoing RP, the secondary bladder cancer was associated with EBRT, ADT, alone or in combination. The secondary colorectal cancer was also associated with receiving either EBRT, BT or ADT.

Prediction model of radiotherapy outcome for Ocular Adnexal Lymphoma using informative features selected by chemometric algorithms.

BACKGROUND: Ocular Adnexal Lymphoma (OAL) is a non-Hodgkin's lymphoma that most often appears in the tissues near the eye, and radiotherapy is the currently preferred treatment. There has been a controversy regarding the prognostic factors for systemic failure of OAL radiotherapy, the thorough evaluation prior to receiving radiotherapy is highly recommended to better the patient's prognosis and minimize the likelihood of any adverse effects. PURPOSE: To investigate the risk factors that contribute to incomplete remission in OAL radiotherapy and to establish a hybrid model for predicting the radiotherapy outcomes in OAL patients. METHODS: A retrospective chart review was performed for 87 consecutive patients with OAL who received radiotherapy between Feb 2011 and August 2022 in our center. Seven image features, derived from MRI sequences, were integrated with 122 clinical features to form comprehensive patient feature sets. Chemometric algorithms were then employed to distill highly informative features from these sets. Based on these refined features, SVM and XGBoost classifiers were performed to classify the effect of radiotherapy. RESULTS: The clinical records of from 87 OAL patients (median age: 60 months, IQR: 52-68 months; 62.1% male) treated with radiotherapy were reviewed. Analysis of Lasso (AUC = 0.75, 95% CI: 0.72-0.77) and Random Forest (AUC = 0.67, 95% CI: 0.62-0.70) algorithms revealed four potential features, resulting in an intersection AUC of 0.80 (95% CI: 0.75-0.82). Logistic Regression (AUC = 0.75, 95% CI: 0.72-0.77) identified two features. Furthermore, the integration of chemometric methods such as CARS (AUC = 0.66, 95% CI: 0.62-0.72), UVE (AUC = 0.71, 95% CI: 0.66-0.75), and GA (AUC = 0.65, 95% CI: 0.60-0.69) highlighted six features in total, with an intersection AUC of 0.82 (95% CI: 0.78-0.83). These features included enophthalmos, diplopia, tenderness, elevated ALT count, HBsAg positivity, and CD43 positivity in immunohistochemical tests. CONCLUSION: The findings suggest the effectiveness of chemometric algorithms in pinpointing OAL risk factors, and the prediction model we proposed shows promise in helping clinicians identify OAL patients likely to achieve complete remission via radiotherapy. Notably, patients with a history of exophthalmos, diplopia, tenderness, elevated ALT levels, HBsAg positivity, and CD43 positivity are less likely to attain complete remission after radiotherapy. These insights offer more targeted management strategies for OAL patients. The developed model is accessible online at: https://lzz.testop.top/.

Focal radiotherapy boost to MR-visible tumor for prostate cancer: a systematic review.

PURPOSE: The FLAME trial provides strong evidence that MR-guided external beam radiation therapy (EBRT) focal boost for localized prostate cancer increases biochemical disease-free survival (bDFS) without increasing toxicity. Yet, there are many barriers to implementation of focal boost. Our objectives are to systemically review clinical outcomes for MR-guided EBRT focal boost and to consider approaches to increase implementation of this technique. METHODS: We conducted literature searches in four databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline. We included prospective phase II/III trials of patients with localized prostate cancer underdoing definitive EBRT with MR-guided focal boost. The outcomes of interest were bDFS and acute/late gastrointestinal and genitourinary toxicity. RESULTS: Seven studies were included. All studies had a median follow-up of greater than 4 years. There were heterogeneities in fractionation, treatment planning, and delivery. Studies demonstrated effectiveness, feasibility, and tolerability of focal boost. Based on the Phoenix criteria for biochemical recurrence, the reported 5-year biochemical recurrence-free survival rates ranged 69.7-100% across included studies. All studies reported good safety profiles. The reported ranges of acute/late grade 3 + gastrointestinal toxicities were 0%/1-10%. The reported ranges of acute/late grade 3 + genitourinary toxicities were 0-13%/0-5.6%. CONCLUSIONS: There is strong evidence that it is possible to improve oncologic outcomes without substantially increasing toxicity through MR-guided focal boost, at least in the setting of a 35-fraction radiotherapy regimen. Barriers to clinical practice implementation are addressable through additional investigation and new technologies.

Second Malignancy Probabilities in Patients With Breast Cancer Treated With Conventional Versus Hypofractionated External Beam Radiation Therapy in the Adjuvant Setting.

AIMS: For women with breast cancer, seminal studies have shown that adjuvant hypofractionated external beam radiation therapy (hEBRT) maintains similar outcomes and may reduce overall costs compared with conventionally fractionated external beam radiation therapy (cEBRT). However, it is unclear whether hEBRT may be associated with differential risk of development of radiation-induced second malignancies compared with cEBRT. Because the occurrence of second malignancies is small, large databases may improve our understanding of the relative risk of second malignancies between hEBRT and cEBRT. MATERIALS AND METHODS: Using the National Cancer Database, we carried out a retrospective cohort analysis of women diagnosed with non-metastatic, stage 0-III breast cancer from 2004 to 2017. All patients had a lumpectomy or mastectomy and a follow-up time of at least 60 months after diagnosis. The probability of second malignancies in women receiving adjuvant cEBRT or hEBRT was compared using multivariable logistic regression adjusting for sociodemographic, geographical, clinical and treatment factors, allowing for relative (but not absolute) comparison of second malignancy risk. Temporal sensitivity analyses stratified by year of diagnosis and length of follow-up time were also conducted. RESULTS: Of the 125 228 women in our study, 115 576 (92.3%) received cEBRT and 9652 (7.71%) received hEBRT. The median age of the cohort was 60 (interquartile range 51-68) years at diagnosis and the median follow-up time was 99.61 (interquartile range 77.5-128.49) months. Upon adjusting for sociodemographic and clinical factors, patients who received hEBRT had no difference in relative risk than patients who received cEBRT (odds ratio 0.937, 95% confidence interval 0.869-1.010, P = 0.091). In analyses stratified by year of diagnosis, and stratified by length of follow-up, there was no difference in second malignancy probability between patients who completed hEBRT and patients who completed cEBRT. CONCLUSIONS: In this analysis of over 120 000 women with non-metastatic breast cancer, hEBRT was not associated with different odds of developing second malignancies compared with cEBRT. Our findings may inform patient counselling in the choice of radiation regimens for breast cancer and further support the safety of hypofractionated regimens for breast cancer.

The contest between internal and external-beam dosimetry: The Zeno's paradox of Achilles and the tortoise.

Radionuclide therapy, also called molecular radiotherapy (MRT), has come of age, with several novel radiopharmaceuticals being approved for clinical use or under development in the last decade. External beam radiotherapy (EBRT) is a well-established treatment modality, with about half of all oncologic patients expected to receive at least one external radiation treatment over their disease course. The efficacy and the toxicity of both types of treatment rely on the interaction of radiation with biological tissues. Dosimetry played a fundamental role in the scientific and technological evolution of EBRT, and absorbed doses to the target and to the organs at risk are calculated on a routine basis. In contrast, in MRT the usefulness of internal dosimetry has long been questioned, and a structured path to include absorbed dose calculation is missing. However, following a similar route of development as EBRT, MRT treatments could probably be optimized in a significant proportion of patients, likely based on dosimetry and radiobiology. In the present paper we describe the differences and the similarities between internal and external-beam dosimetry in the context of radiation treatments, and we retrace the main stages of their development over the last decades.

[Personalized approach to anaplastic thyroid carcinoma]. / Personalisiertes Vorgehen beim anaplastischen Schilddrüsenkarzinom.

BACKGROUND: Anaplastic thyroid carcinoma (ATC) represents the rarest but most aggressive tumor entity of the thyroid gland. In this respect, the treatment of advanced ATC has rapidly evolved in recent years. Recently, new personalized forms of treatment that address the somatic mutational status of the tumor have been increasingly used. The aim of this article is to provide an overview of current molecular-based and personalized treatment options for ATC. METHODS: A current literature search was performed with a focus on personalized molecular-based treatment options for ATC. RESULTS: The majority of patients suffering from ATC have an advanced tumor disease at the time of initial diagnosis. Despite multimodal treatment approaches consisting of surgery, external beam radiation therapy (EBRT) and chemotherapy (CTX), the prognosis of ATC is still poor. Accordingly, the focus of innovative treatment approaches is on molecular-based, individualized tumor therapy, including in particular BRAFV600E and multikinase inhibitors. The potential of the latter seems to lie particularly in combination therapy with immune checkpoint inhibitors. These treatment options can be used in both adjuvant and neoadjuvant settings. Neoadjuvant treatment of advanced ATC can achieve a potentially resectable treatment setting and improve the poor prognosis of affected patients; however, larger prospective and randomized studies on these combination therapies are currently pending. CONCLUSION: The focus of future treatment approaches for ATC will be on individualized, molecular-based tumor therapy. In particular, the neoadjuvant use of these therapies may change the paradigm of ATC surgery as locally advanced as well as metastatic carcinomas can be converted to a potentially resectable status and made amenable to surgery.

Previous external beam radiation therapy for pelvic malignancy increases complications of total hip arthroplasty.

INTRODUCTION: External beam radiation therapy (EBRT) has known effects on bone health. No large database studies have looked at the effects of pelvic EBRT on total hip arthroplasty (THA) outcomes. The purpose of this study was to evaluate 90-day and long-term (>2 years) complication rates following THA in patients with a history of pelvic malignancy and EBRT. METHODS: Patients were retrospectively identified using a national insurance claims database. Subjects who underwent THA for osteoarthritis or avascular necrosis were included if they had at least 2-year follow-up and were stratified into 3 cohorts: (1) prior pelvic malignancy diagnosis (prostate, cervical, uterine, ovarian, or rectal) and EBRT (Group A); (2) prior malignancy diagnosis but no EBRT (Group B); and (3) neither prior malignancy diagnosis nor EBRT (Group C). Univariate and multivariate analyses were conducted to evaluate for an association between prior EBRT and the incidence of 90-day and 2-year complication rates using chi-square, student t-tests, and logistic regression analyses where appropriate. RESULTS: 671,554 patients met the inclusion criteria. Group A had higher odds of all-cause revision, septic revision, and loosening with revision after 2 years when compared to Group C and Group B (p < 0.001). Group A subjects had higher rates of 90-day deep vein thrombosis, sepsis, and stroke (p < 0.001) than groups B and C. CONCLUSIONS: Prior EBRT for pelvic malignancy was associated with significantly increased rates of all-cause revision, septic revision, and loosening as well as 90-day medical complications.

Upper limit of radiation treatment portals in rectal cancer: is it wise to keep using bony landmarks in the present era of 3D conformal treatment?

Background: This study aimed to compare the levels of L5-S1 interspace and the bifurcation of common iliac vessels on simulation images of rectal cancer patients to evaluate the adequacy of superior borders in conventional 2D planning for covering internal iliac vessels. Materials and methods: Simulation images of 236 rectal cancer patients who received neoadjuvant chemoradiation and surgery were analyzed. The images were retrieved from the radiation treatment database and included delineations of L5-S1 interspace and common iliac vessel bifurcation. Distances between these landmarks were measured. Results: Among the 236 patients, the majority had the common iliac artery bifurcation positioned above the L5-S1 interspace. Specifically, 78.3% of patients had the right common iliac bifurcation above L5-S1 interspace, with an average distance of 2.02 cm. For the left common iliac artery, 77.11% of patients had the bifurcation above L5-S1 interspace, with an average distance of 1.99 cm. Notably, there were cases where the bifurcations were not at the same level. Conclusion: Using the L5-S1 junction as the upper border of the treatment portal may result in missing proximal nodes at risk of metastases. However, further research is needed to determine the significance of failures above the L5-S1 interspace for justifying the inclusion of the common iliac artery bifurcation in the treatment portal.