Cardiovascular Complications of Cranial and Neck Radiation

Lauric acid-based thermosensitive delivery system for the treatment of head and neck squamous cell carcinoma

Traditional treatments for head and neck squamous cell carcinoma (HNSCC) such as surgery, radiation therapy, and chemotherapy, often have severe side effects. Local delivery of chemotherapeutic agents can be a promising approach to minimise systemic toxicity and improve efficacy. Lauric acid (LA), was explored as a novel injectable thermosensitive drug reservoir as a depot for sustained release of anticancer drugs to treat HNSCC. LA was characterised in terms of melting temperature and gelation time. The efficacy of LA-based drug formulations was tested in vitro in a HNSCC cell line and in vivo in a mouse model of HNSCC. LA was modified to have a melting point of 38.5 °C and a gelation time of 40 s at 37.5 °C, rendering it suitable for injection at body temperature. LA- based doxorubicin (DOXO) formulation showed slow release with a maximum of 18% release after 3 days. The in vitro study showed that LA enhanced the cytotoxic effect of DOXO. LA combined with DOXO prevented tumour progression and LA alone significantly reduced the original tumour volume compared to the untreated control group. These findings confirmed that LA can function as practical carrier for the local delivery of chemotherapeutics and provides a safe and simple strategy for the delivery of hydrophobic anticancer drugs and warrant further testing in clinical trials.

Effect of radiotherapy on cardiac-specific death in patients with non-malignant tumors of central nervous system and related clinical features

Importance

Cardiac-specific death from radiation caused by radiation therapy (RT) in patients with malignant tumors has received extensive attention, however, little is known regarding the potential cardiotoxic effects of RT in patients with non-malignant tumors.

Objectives and methods

In this study, we used the SEER data to explore the incidence of post-radiation cardiovascular complications in patients with non-malignant tumors of central nervous system (CNS), and identify the influencing factors of cardiac-specific death.

Results

Ultimately 233, 306 patients were included (97.8% of patients had brain tumors and 2.2% had spinal cord tumors). For patients with non-malignant tumors of CNS, RT {yes (odds ratio [OR] 0.851, 95% confidence interval [CI] 0.774–0.936, p = 0.001, before propensity score matching (PSM); OR 0.792, 95% CI 0.702–0.894, p < 0.001, after PSM) vs. no} was associated with lower risk of cardiac-specific death, other clinical features affecting cardiac death similar to those in patients with non-malignant tumors of CNS receiving RT. For patients with non-malignant tumors of CNS receiving RT, female, married status, Hispanic ethnicity, surgery, and tumor site (brain exclude nerve and endocrine, nervous system) were associated with lower risks of cardiac-specific death, while earlier year of diagnosis, older age of diagnosis, Black, larger tumor and bilateral tumor were risk factors for cardiac-specific death.

Conclusions

Our study shows the influencing factors for cardiac-specific death in patients with non-malignant tumors of CNS, and found RT is associated with lower risk of cardiac-specific death. These results can facilitate the identification of patients with non-malignant tumors of CNS who can benefit from RT while avoiding cardiovascular events. In addition, this study helps to enhance the clinical use of RT in these populations, especially in patients who may have impaired cardiac function due to CNS tumors.

Application of deep learning to auto-delineation of target volumes and organs at risk in radiotherapy

The technological advancement heralded the arrival of precision radiotherapy (RT), thereby increasing the therapeutic ratio and decreasing the side effects from treatment. Contour of target volumes (TV) and organs at risk (OARs) in RT is a complicated process. In recent years, automatic contouring of TV and OARs has rapidly developed due to the advances in deep learning (DL). This technology has the potential to save time and to reduce intra- or inter-observer variability. In this paper, the authors provide an overview of RT, introduce the concept of DL, summarize the data characteristics of the included literature, summarize the possible challenges for DL in the future, and discuss the possible research directions.

Vasculometabolic effects in patients with congenital growth hormone deficiency with and without GH replacement therapy during adulthood

PURPOSE

To evaluated the metabolic profiles and vascular properties in congenital growth hormone (GH) deficiency (GHD) and its replacement in adults.

PATIENTS AND METHODS

Cross-sectional study conducted in a single tertiary center for pituitary diseases. Eighty-one adult subjects were divided into three groups: (1) 29 GHD patients with daily subcutaneous GH replacement therapy (GHRT) during adulthood; (2) 20 GHD patients without GHRT during adulthood and (3) 32 controls. Only patients with adequate adherence to others pituitary hormone deficiencies were included. Anthropometric parameters, body composition by dual-energy X-ray absorptiometry, metabolic profiles and vascular properties (carotid intima media thickness, pulse wave velocity and flow-mediated dilation) were compared among the groups.

RESULTS

Waist-to-height ratio (WHR), body fat percentages and fat mass index (FMI) were lower in patients with GHRT than patients without GHRT during adulthood (0.49 ± 0.06 vs. 0.53 ± 0.06 p = 0.026, 30 ± 10 vs. 40 ± 11 p = 0.003 and 7.3 ± 4 vs. 10 ± 3.5 p = 0.041, respectively). In addition, association between longer GHRT and lower body fat percentage was observed (r =  - 0.326, p = 0.04). We found higher triglyceride (113.5 ± 62 vs. 78 ± 36, p = 0.025) and lower HDL cholesterol (51 ± 17 vs. 66 ± 23, p = 0.029) levels in patients without GHRT during adulthood in comparison to controls. No statistical differences were observed for vascular properties among the groups.

CONCLUSIONS

No differences in vascular properties were observed in congenital GHD adult patients with or without GHRT despite patients without GHRT had an unfavorable body composition. GHRT currently remains an individualized decision in adults with GHD and these findings bring new insight into the treatment and follow-up of these patients.

Combinatorial drug therapy in cancer - New insights

Cancer can arise due to mutations in numerous pathways present in our body and thus has many alternatives for getting aggravated. Due to this attribute, it gets difficult to treat cancer patients with monotherapy alone and has a risk of not being eliminated to the full extent. This necessitates the introduction of combinatorial therapy as it employs cancer treatment using more than one method and shows a greater success rate. Combinatorial therapy involves a complementary combination of two different therapies like a combination of radio and immunotherapy or a combination of drugs that can target more than one pathway of cancer formation like combining CDK targeting drugs with Growth factors targeting drugs. In this review, we discuss the various aspects of cancer which include, its causes; four regulatory mechanisms namely: apoptosis, cyclin-dependent kinases, tumor suppressor genes, and growth factors; some of the pathways involved; treatment: monotherapy and combinatorial therapy and combinatorial drug formulation in chemotherapy. The present review gives a holistic account of the different mechanisms of therapies and also drug combinations that may serve to not only complement the monotherapy but can also surpass the resistance against monotherapy agents.

Emerging Challenges of Radiation-Associated Cardiovascular Dysfunction (RACVD) in Modern Radiation Oncology: Clinical Practice, Bench Investigation, and Multidisciplinary Care

Radiotherapy (RT) is a crucial treatment modality in managing cancer patients. However, irradiation dose sprinkling to tumor-adjacent normal tissues is unavoidable, generating treatment toxicities, such as radiation-associated cardiovascular dysfunction (RACVD), particularly for those patients with combined therapies or pre-existing adverse features/comorbidities. Radiation oncologists implement several efforts to decrease heart dose for reducing the risk of RACVD. Even applying the deep-inspiration breath-hold (DIBH) technique, the risk of RACVD is though reduced but still substantial. Besides, available clinical methods are limited for early detecting and managing RACVD. The present study reviewed emerging challenges of RACVD in modern radiation oncology, in terms of clinical practice, bench investigation, and multidisciplinary care. Several molecules are potential for serving as biomarkers and therapeutic targets. Of these, miRNAs, endogenous small non-coding RNAs that function in regulating gene expression, are of particular interest because low-dose irradiation, i.e., 200 mGy (one-tenth of conventional RT daily dose) induces early changes of pro-RACVD miRNA expression. Moreover, several miRNAs, e.g., miR-15b and miR21, involve in the development of RACVD, further demonstrating the potential bio-application in RACVD. Remarkably, many RACVDs are late RT sequelae, characterizing highly irreversible and progressively worse. Thus, multidisciplinary care from oncologists and cardiologists is crucial. Combined managements with commodities control (such as hypertension, hypercholesterolemia, and diabetes), smoking cessation, and close monitoring are recommended. Some agents show abilities for preventing and managing RACVD, such as statins and angiotensin-converting enzyme inhibitors (ACEIs); however, their real roles should be confirmed by further prospective trials.

[Curing cancer and protecting the heart : Challenges in cardio-oncology in the era of modern tumor treatment]

Recent advances in the medical oncological treatment options for cancer have led to a clear improvement in the survival rate worldwide; however, many of the recently developed new drugs are directly or indirectly associated with cardiovascular side effects. Cardiovascular diseases are already the most frequent non-cancerous cause of death in tumor patients. Prevention, early detection of these complications, correct management and timely initiation of specific cardiac medical treatment are the key for an improvement of the cardiovascular prognosis. This article provides an overview and comprehensive summary of the possible cardiotoxic side effects of important oncological therapies and offers possible practical strategies with respect to risk stratification, cardiological follow-up care and management approaches for chemotherapy-induced left ventricular dysfunction.

Clinical Outcomes after Transcatheter Aortic Valve Replacement in Cancer Survivors Treated with Ionizing Radiation

BACKGROUND

Improved cancer survival in patients treated with thoracic ionizing radiation (XRT) has resulted in unanticipated surge of aortic stenosis. Transcatheter aortic valve replacement (TAVR) has revolutionized the management of severe aortic stenosis. However, long-term clinical outcomes in radiation-exposed cohorts undergoing TAVR are unknown. We compared the all-cause mortality and major adverse cardiac events (MACE) in patients with prior chest XRT (C-XRT) undergoing TAVR.

METHODS

This is an observational cohort study in subjects who underwent TAVR for symptomatic severe aortic stenosis from 2012 to 2017 in a tertiary care referral center. We examined the all-cause mortality and MACE using cox proportional hazard analysis to identify the clinical predictors of survival in the cohort of patients who had a history of prior C-XRT for malignancy.

RESULTS

Of the 610 patients who underwent TAVR for symptomatic severe aortic stenosis, 75 had prior C-XRT. The majority of C-XRT patients had prior breast cancer (44%) followed by Hodgkin's lymphoma (31%), with the median time from XRT to TAVR of 19.0 years. During a mean follow up of 17.1 months after TAVR, all-cause mortality was 17%. Those with prior C-XRT had higher all-cause mortality (XRT: 29%; non-XRT:15%, p<0.01) and MACE (XRT: 57%; non-XRT: 27%, p<0.001) after TAVR. Patients with prior XRT had a higher incidence of atrial fibrillation (XRT: 48 %; non-XRT: 2.4%, p<0.01) and high-grade heart block (XRT: 20%; non-XRT: 9.1%, p=0.007) requiring pacemaker implant after TAVR. On multivariate cox proportional hazard analysis, prior XRT (HR: 2.07, p=0.003), poor renal function (HR: 1.29, p<0.001) and post-operative anemia requiring transfusion (HR: 1.16, p:0.001) were the strongest predictors of reduced survival.

CONCLUSIONS

Cancer survivors with prior C- XRT have higher incidence of all-cause mortality and MACE after TAVR. Careful patient selection and follow-up strategies are needed to improve outcomes.

Silencing of XRCC4 increases radiosensitivity of triple-negative breast cancer cells

Background: Radiotherapy is an important locoregional treatment, and its effect on triple-negative breast cancer (TNBC) needs to be enhanced. The aim of the present study was to investigate the potential effects of XRCC4 on radiosensitivity of TNBC. Methods: The RNAi technique was implemented to establish the TNBC stable cell line with XRCC4 knockdown. MTT assay was used to detect the effect of XRCC4 knockdown on cell proliferation. Western blot and immunohistochemistry assays were employed to identify protein expression. Colony assay was performed to detect the effect of XRCC4 knockdown on the colony formation ability of TNBC cells with radiation treatment. Comet assay was conducted to evaluate the influence of XRCC4 silencing on DNA repair activity in ionizing radiation. In addition, we performed a survival analysis based on data in TCGA database. Results: XRCC4 knockdown by lentivirus-mediated shRNA had no significant effect on proliferation of TNBC cells. Knockdown of XRCC4 could substantially increase the sensitivity of TNBC cells to ionizing radiation. The DNA damage level was detected to be increased in the XRCC4 knockdown group, indicating there was a significant repair delay in the XRCC4-deleted cells. Clinical sample analysis exhibited that there were various XRCC4 expression in different patients with TNBC. Moreover, survival analysis showed that high expression of XRCC4 was significantly associated with poor progression-free survival after radiotherapy in TNBC patients. Conclusion: Our findings suggest that XRCC4 knockdown sensitizes TNBC cells to ionizing radiation, and could be considered as a novel predictor of radiosensitivity and a promising target for TNBC.

Cardiovascular effects of radiation therapy

Radiation therapy (RT) plays a prominent role in the treatment of many cancers. With increasing use of RT and high overall survival rates, the risks associated with RT must be carefully considered. Of these risks, the cardiovascular and autonomic toxicities have been of significant concern. In fact, cardiovascular disease is the leading cause of nonmalignancy-related death in cancer survivors. The manifestations of radiation induced cardiac injury include the acute toxicities of myopericarditis and late toxicities including constrictive pericarditis, restrictive cardiomyopathy, coronary artery disease, valvular heart disease, heart failure, and conduction abnormalities. Neck and cranial RT have also been associated with significant long-term toxicities including accelerated occlusive carotid artery disease, autonomic dysfunction due to baroreceptor damage, and development of metabolic syndromes due to damage to the hypothalamic-pituitary axis. The clinical manifestations of radiation induced disease may not present until several years following the delivery of radiation. We review the adverse effects of RT on these organ systems and discuss risk reduction strategies that may effectively mitigate some of these adverse outcomes.