Evaluation of a blood miRNA/mRNA signature to follow-up Lu-PRRT therapy for G1/G2 intestinal neuroendocrine tumors.

Background: 177Lu-oxodotreotide peptide receptor therapy (LuPRRT) is an efficient treatment for midgut neuroendocrine tumors (NETs) of variable radiological response. Several clinical, biological, and imaging parameters may be used to establish a relative disease prognosis but none is able to predict early efficacy or toxicities. We investigated expression levels for mRNA and miRNA involved in radiosensitivity and tumor progression searching for correlations related to patient outcome during LuPRRT therapy. Methods: Thirty-five patients received LuPRRT for G1/G2 midgut NETs between May 2019 and September 2021. Peripheral blood samples were collected prior to irradiation, before and 48 h after the second and the fourth LuPRRT, and at 6-month follow-up. Multiple regression analyses and Pearson correlations were performed to identify the miRNA/mRNA signature that will best predict response to LuPRRT. Results: Focusing on four mRNAs and three miRNAs, we identified a miRNA/mRNA signature enabling the early identification of responders to LuPRRT with significant reduced miRNA/mRNA expression after the first LuPRRT administration for patients with progressive disease at 1 year (p < 0.001). The relevance of this signature was reinforced by studying its evolution up to 6 months post-LuPRRT. Moreover, nadir absolute lymphocyte count within the first 2 months after the first LuPRRT administration was significantly related to low miRNA/mRNA expression level (p < 0.05) for patients with progressive disease. Conclusion: We present a pilot study exploring a miRNA/mRNA signature that correlates with early hematologic toxicity and therapeutic response 12 months following LuPRRT. This signature will be tested prospectively in a larger series of patients.

Breakthrough of Hypoxia Limitation by Tumor-Targeting Photothermal Therapy-Enhanced Radiation Therapy.

Purpose: To address the problem of suboptimal reactive oxygen species (ROS) production in Radiation therapy (RT) which was resulted from exacerbated tumor hypoxia and the heterogeneous distribution of radiation sensitizers. Materials and Methods: In this work, a novel nanomedicine, designated as PLGA@IR780-Bi-DTPA (PIBD), was engineered by loading the radiation sensitizer Bi-DTPA and the photothermal agent IR780 onto poly(lactic-co-glycolic acid) (PLGA). This design leverages the tumor-targeting ability of IR780 to ensure selective accumulation of the nanoparticles in tumor cells, particularly within the mitochondria. The effect of the photothermal therapy-enhanced radiation therapy was also examined to assess the alleviation of hypoxia and the enhancement of radiation sensitivity. Results: The PIBD nanoparticles exhibited strong capacity in mitochondrial targeting and selective tumor accumulation. Upon activation by 808 nm laser irradiation, the nanoparticles effectively alleviated local hypoxia by photothermal effect enhanced blood supplying to improve oxygen content, thereby enhancing the ROS production for effective RT. Comparative studies revealed that PIBD-induced RT significantly outperformed conventional RT in treating hypoxic tumors. Conclusion: This design of tumor-targeting photothermal therapy-enhanced radiation therapy nanomedicine would advance the development of targeted drug delivery system for effective RT regardless of hypoxic microenvironment.

The predictors of lymphopenia and its effects on survival in locally advanced esophageal squamous cell carcinoma.

To investigate the impact of the effective radiation dose to immune cells (EDIC) and gross tumor volume (GTV) on lymphopenia and survival in patients with locally advanced esophageal squamous cell carcinoma (LAESCC). Between January 2013 and December 2020, 272 LAESCC patients were treated with definitive radiotherapy in two institutions. Based on radiation doses to the lungs, heart, and body region scanned, EDIC was calculated as an equal uniform dose to the total blood considering blood flow and fraction effect. The radiotherapy plan was used to calculate the GTVs. Lymphopenia was graded based on the lowest lymphocyte count during RT. The overall survival (OS), progress-free survival (PFS), and local recurrence-free survival (LRFS) were analyzed statistically. The lowest lymphocyte count was significantly correlated with EDIC (r= -0.389, p < .001) and GTV (r= -0.211, p < .001). Lymphopenia, EDIC, and GTV are risk factors for patients with ESCC. In a Kaplan-Meier analysis with EDIC and GTV as stratification factors, lymphopenia was not associated with OS in the EDIC>12.9 Gy group (p = .294)and EDIC ≤ 12.9 Gy group, and it was also not associated with OS in GTV>68.8 cm3 group (p = .242) and GTV ≤ 68.8 cm3 group(p = .165). GTV and EDIC had an impact on the relationship between lymphopenia and OS in patients with LAESCC undergoing definitive RT. Poorer OS, PFS, and LRFS are correlated with lymphopenia, higher EDIC, and larger GTV.

Results of the study of factors predicting the risk of the development of grade III radiation-induced mucositis during radiation or chemoradiation therapy in patients with oral cavity and oropharynx cancer.

BACKGROUND: Today, a number of methods and ways of prevention and treatment of radiation- -induced mucositis of the oral cavity and oropharynx have been developed, but the represented approaches are still not effective enough. Therefore, to increase the effectiveness of the prevention and treatment of radiation-induced mucositis, it is necessary to approach this problem comprehensively and individually, and to evaluate the factors affecting the development of mucositis. MATERIALS AND METHODS: In this single-center prospective controlled non-randomized clinical trial, the results of clinical observation of the development of complications of radiation and chemoradiation therapy in 105 patients with a newly diagnosed squamous cell cancer of the oral cavity and oropharynx were analyzed. Factors affecting the risk of the development of grade III radiation-induced mucositis including the age, gender of the patients, their general condition before the treatment according to World Health Organisation scales, type of the treatment and its doses, additional use of immunotherapy with alpha/beta defensins, characteristic signs of the tumor process and all indices of the immune status of the patients before the treatment have been analyzed. RESULTS: The method of construction and analysis of one-factor logistic regression models, where 24 indices were analyzed as factorial features, showed that the reduction of the risk of the development of grade III radiation-induced mucositis is predicted by several factors: immunotherapy, gender, serum concentrations of IgG and IgA. A decrease (P < 0.001) in the risk of the development of grade III radiation-induced mucositis was revealed if immunotherapy with alpha/beta defensins (with a total dose of 40 mg) was included into the treatment scheme (relative odds (RO) 0.05; 95% reference interval (RI) 0.02-0.18), in comparison with patients of the groups where it was not present or this immune agent was used in a total dose of 60 mg (P = 0.001, RO 0.06; 95% RI 0.01-0.30). The next factorial sign was gender, namely the risk of the development of grade III radiation-induced mucositis was lower for men (P = 0.003; RO 0.15; 95% RI 0.04-0.53) compared to women. An increase (P = 0.024) in the risk of the development of grade III radiation-induced mucositis with an increase in the initial level of IgG serum concentration was revealed, (RO 1.08; 95% RI 1.01-1.16) for each 1 mg/mL, as well as an increase (P = 0.044) in the possibility of the appearance of grade III radiation-induced mucositis with an increase in the serum concentration of IgA (RO 1.23; 95% RI 1.01-1.50) for every 1 mg/mL also before the beginning of the treatment. Multifactorial analysis has also confirmed that the risk of the development of grade III radiation-induced mucositis increases (P = 0.008) with a high serum IgG concentration before the treatment or with an increase in this index during therapy (RO 1.13; 95% RI 1.03-1.09) for every 1 mg/mL (when standardized by other risk factors). It was determined that when standardizing according to other factors (gender, IgG level), the risk of the development of grade III radiation-induced mucositis in the use of the immune agent alpha/beta defensins in a total dose of 40 mg per course decreases (P < 0.001; RO 0.08; 95% RI 0.02-0.27) compared to patients with oral cavity and oropharynx cancer who were not treated with immunotherapy. The risk of the development of grade III radiation-induced mucositis also decreases (P = 0.001) in the use of immunotherapy in a higher dose, i.e. 60 mg per course (RO 0.03; 95% RI 0.004-0.24 compared to patients whose treatment did not include immunotherapy (when standardized by other factors). CONCLUSION: As a result of this controlled clinical study, some factors were determined in addition to the radiation as those affecting the risk of the development of grade III radiation-induced mucositis in patients with oral cavity and oropharynx cancer during special treatment. These factors comprise the inclusion of immunotherapy with alpha/beta defensins into the specific treatment; gender, and baseline levels of serum IgG and IgA concentrations suggest a pattern in which the higher the serum IgG and IgA concentrations are before the start of the treatment, the greater is the likelihood of severe radiation-induced mucositis degree during special therapy. The results of the study of humoral state of the immune system in patients with oral cavity and oropharynx cancer before the beginning of chemoradiation therapy can be used as prognostic risk factors for the development of severe gamma-irradiation-induced mucositis of the oropharyngeal area, as well as an indication for the use of immunotherapeutic agents (in particular, alpha/beta defensins) that are able to polarize the immune response towards type 1 T-helpers through their immunomodulatory action.

Survival outcomes and failure patterns for oropharyngeal cancers treated with simultaneous integrated boost in intensity modulated radiotherapy (SIB-IMRT) and concurrent chemotherapy.

BACKGROUND: Intensity modulated radiotherapy (IMRT) has become a standard radiotherapy treatment delivery option owing to the advantages it offers in terms of target coverage and organ sparing. Furthermore, the ability to introduce different fractionation for different targets lets us deliver higher doses to the high-risk areas and lower doses to the elective volumes at the same sitting, referred to as simultaneous integrated boost (SIB). In the current study, we intended to retrospectively analyze the clinical outcomes and patterns of the failure of oropharyngeal cancers treated with SIB-IMRT and concurrent chemotherapy at our centre and analyze the factors contributing to poorer outcomes. MATERIAL AND METHODS: Data of oropharyngeal cancer patients treated with SIB-IMRT and concurrent chemotherapy were retrieved from the institutional database. Patient demographic details, histopathological features, staging, treatment details, failure patterns and outcomes were documented. All potential factors were evaluated for outcomes. Radiation was delivered by using the SIB-IMRT technique. High-risk planning target volume (PTV) received 66 Gy in 2.2 Gy/fraction, intermediate and low-risk PTV received 60 Gy and 54 Gy, respectively. Primary endpoint was to assess local control (LC), regional control (RC) and loco-regional control (LRC) rates and secondary end point was to evaluate the survival outcomes - overall survival (OS) and cancer-specific mortality. All survival analyzes were performed using the Kaplan-Meier method. RESULTS: A total of 169 cases were included in the final analysis. The median age was 55 years (range 20-78) with 95.3% males. The base of tongue was the most common primary site. Around 54% cases were node negative with 38% patients having stage IV disease. The local control rates for N0 vs. N+ cases were 74.1 vs. 62.3% (P = 0.046), respectively. Similarly, the 4-year RC rates for N0 vs. N+ cases were 94.4 vs. 83.5% (P = 0.024), respectively. On multivariate analysis, only 4-year RC rates showed significant difference between the two (P = 0.039). No differences were found between T stages in LRC and OS. The 4-year LRC rates for stages 1, 2 vs. 3, 4 were non-significant (69.2 vs. 66.3%; P = 0.178). The 4-year OS rate was 81.3%. The 4-year LC and LRC rates were 67.8 and 89.5%, respectively. There were 54 local and 17 regional failures. The median time to failure was 13 months (range 3.6-82.9). CONCLUSION: SIB-IMRT provides comparable outcomes for oropharyngeal cancers. OS and loco-regional recurrences were significantly worse for nodal positive disease.

Transcriptomic response of prostate cancer cells to carbon ion and photon irradiation with focus on androgen receptor and TP53 signaling.

BACKGROUND: Radiotherapy is essential in the treatment of prostate cancer. An alternative to conventional photon radiotherapy is the application of carbon ions, which provide a superior intratumoral dose distribution and less induced damage to adjacent healthy tissue. A common characteristic of prostate cancer cells is their dependence on androgens which is exploited therapeutically by androgen deprivation therapy in the advanced prostate cancer stage. Here, we aimed to analyze the transcriptomic response of prostate cancer cells to irradiation by photons in comparison to carbon ions, focusing on DNA damage, DNA repair and androgen receptor signaling. METHODS: Prostate cancer cell lines LNCaP (functional TP53 and androgen receptor signaling) and DU145 (dysfunctional TP53 and androgen receptor signaling) were irradiated by photons or carbon ions and the subsequent DNA damage was assessed by immuno-cytofluorescence. Furthermore, the cells were treated with an androgen-receptor agonist. The effects of irradiation and androgen treatment on the gene regulation and the transcriptome were investigated by RT-qPCR and RNA sequencing, followed by bioinformatic analysis. RESULTS: Following photon or carbon ion irradiation, both LNCaP and DU145 cells showed a dose-dependent amount of visible DNA damage that decreased over time, indicating occurring DNA repair. In terms of gene regulation, mRNAs involved in the TP53-dependent DNA damage response were significantly upregulated by photons and carbon ions in LNCaP but not in DU145 cells, which generally showed low levels of gene regulation after irradiation. Both LNCaP and DU145 cells responded to photons and carbon ions by downregulation of genes involved in DNA repair and cell cycle, partially resembling the transcriptome response to the applied androgen receptor agonist. Neither photons nor carbon ions significantly affected canonical androgen receptor-dependent gene regulation. Furthermore, certain genes that were specifically regulated by either photon or carbon ion irradiation were identified. CONCLUSION: Photon and carbon ion irradiation showed a significant congruence in terms of induced signaling pathways and transcriptomic responses. These responses were strongly impacted by the TP53 status. Nevertheless, irradiation mode-dependent distinct gene regulations with undefined implication for radiotherapy outcome were revealed. Androgen receptor signaling and irradiations shared regulation of certain genes with respect to DNA-repair and cell-cycle.

Clinical application of a GPU-accelerated monte carlo dose verification for cyberknife M6 with Iris collimator.

PURPOSE: To apply an independent GPU-accelerated Monte Carlo (MC) dose verification for CyberKnife M6 with Iris collimator and evaluate the dose calculation accuracy of RayTracing (TPS-RT) algorithm and Monte Carlo (TPS-MC) algorithm in the Precision treatment planning system (TPS). METHODS: GPU-accelerated MC algorithm (ArcherQA-CK) was integrated into a commercial dose verification system, ArcherQA, to implement the patient-specific quality assurance in the CyberKnife M6 system. 30 clinical cases (10 cases in head, and 10 cases in chest, and 10 cases in abdomen) were collected in this study. For each case, three different dose calculation methods (TPS-MC, TPS-RT and ArcherQA-CK) were implemented based on the same treatment plan and compared with each other. For evaluation, the 3D global gamma analysis and dose parameters of the target volume and organs at risk (OARs) were analyzed comparatively. RESULTS: For gamma pass rates at the criterion of 2%/2 mm, the results were over 98.0% for TPS-MC vs.TPS-RT, TPS-MC vs. ArcherQA-CK and TPS-RT vs. ArcherQA-CK in head cases, 84.9% for TPS-MC vs.TPS-RT, 98.0% for TPS-MC vs. ArcherQA-CK and 83.3% for TPS-RT vs. ArcherQA-CK in chest cases, 98.2% for TPS-MC vs.TPS-RT, 99.4% for TPS-MC vs. ArcherQA-CK and 94.5% for TPS-RT vs. ArcherQA-CK in abdomen cases. For dose parameters of planning target volume (PTV) in chest cases, the deviations of TPS-RT vs. TPS-MC and ArcherQA-CK vs. TPS-MC had significant difference (P < 0.01), and the deviations of TPS-RT vs. TPS-MC and TPS-RT vs. ArcherQA-CK were similar (P > 0.05). ArcherQA-CK had less calculation time compared with TPS-MC (1.66 min vs. 65.11 min). CONCLUSIONS: Our proposed MC dose engine (ArcherQA-CK) has a high degree of consistency with the Precision TPS-MC algorithm, which can quickly identify the calculation errors of TPS-RT algorithm for some chest cases. ArcherQA-CK can provide accurate patient-specific quality assurance in clinical practice.

Localized fine-tuning and clinical evaluation of deep-learning based auto-segmentation (DLAS) model for clinical target volume (CTV) and organs-at-risk (OAR) in rectal cancer radiotherapy.

BACKGROUND AND PURPOSE: Various deep learning auto-segmentation (DLAS) models have been proposed, some of which have been commercialized. However, the issue of performance degradation is notable when pretrained models are deployed in the clinic. This study aims to enhance precision of a popular commercial DLAS product in rectal cancer radiotherapy by localized fine-tuning, addressing challenges in practicality and generalizability in real-world clinical settings. MATERIALS AND METHODS: A total of 120 Stage II/III mid-low rectal cancer patients were retrospectively enrolled and divided into three datasets: training (n = 60), external validation (ExVal, n = 30), and generalizability evaluation (GenEva, n = 30) datasets respectively. The patients in the training and ExVal dataset were acquired on the same CT simulator, while those in GenEva were on a different CT simulator. The commercial DLAS software was first localized fine-tuned (LFT) for clinical target volume (CTV) and organs-at-risk (OAR) using the training data, and then validated on ExVal and GenEva respectively. Performance evaluation involved comparing the LFT model with the vendor-provided pretrained model (VPM) against ground truth contours, using metrics like Dice similarity coefficient (DSC), 95th Hausdorff distance (95HD), sensitivity and specificity. RESULTS: LFT significantly improved CTV delineation accuracy (p < 0.05) with LFT outperforming VPM in target volume, DSC, 95HD and specificity. Both models exhibited adequate accuracy for bladder and femoral heads, and LFT demonstrated significant enhancement in segmenting the more complex small intestine. We did not identify performance degradation when LFT and VPM models were applied in the GenEva dataset. CONCLUSIONS: The necessity and potential benefits of LFT DLAS towards institution-specific model adaption is underscored. The commercial DLAS software exhibits superior accuracy once localized fine-tuned, and is highly robust to imaging equipment changes.

Peptide Conjugated Boron Neutron Capture Therapy for Enhanced Tumor Targeting.

A cutting-edge non-invasive cancer treatment method called boron neutron capture therapy (BNCT) allows for the removal of cancerous tumor cells with the least possible damage to healthy tissue. It involves the exposure of cancer cells with low-energy thermal neutrons, boron-10 (10B) cellular uptake causes cancer cell death by producing alpha particles and recoiling lithium-7 (7 Li) nuclei. Despite positive outcomes from clinical trials conducted all around the world, these substances have relatively limited tumor selectivity or low boron content per molecule. The development of new boron delivery agents with more selectivity and enhanced boron loading would advance this technique and promote its use in clinics as a primary cancer treatment. As peptide-binding cell surface receptors are typically overexpressed on cancer cells, they can be seen as interesting targets for targeted tumor therapy. The attachment of meta-carboranes to peptide conjugates that target tumor cells specifically by their overexpressed receptors may be a method to get around these problems. A state-of-the-art overview of current developments in the application of BNCT for cancer targeted therapy via peptide conjugation is the goal of this review.

Risk factors for nausea and vomiting requiring the daily administration of 5-HT3 receptor antagonists in radiotherapy combined with temozolomide for high-grade glioma.

Radiotherapy combined with temozolomide (TMZ+RT) is the primary treatment for high-grade glioma. TMZ is classified as a moderate emetic risk agent and, thus, supportive care for nausea and vomiting is important. In Nagoya University Hospital, all patients are treated with a 5-hydroxy-tryptamine 3 receptor antagonist (5-HT3RA) for the first 3 days. The daily administration of 5-HT3RA is resumed after the 4th day based on the condition of patients during TMZ+RT. Therefore, the present study investigated risk factors for nausea and vomiting in patients requiring the daily administration of 5-HT3RA. Patients with high-grade glioma who received TMZ+RT between January 2014 and December 2019 at our hospital were included. Patients were divided into two groups: a control group (patients who did not resume 5-HT3RA) and resuming 5-HT3RA group (patients who resumed 5-HT3RA after the 4th day), and both groups were compared to identify risk factors for nausea and vomiting during TMZ+RT. There were 78 patients in the control group (68%) and 36 in the resuming 5-HT3RA group (32%). A multivariate analysis of patient backgrounds in the two groups identified age <18 years, PS 2 or more, and occipital lobe tumors as risk factors for nausea and vomiting. Nausea and vomiting were attenuated in 30 patients (83%) in the resuming 5-HT3RA group following the resumption of 5-HT3RA. The results obtained highlight the importance of extracting patients with these risk factors before the initiation of therapy and the early resumption or daily administration of 5-HT3RA according to the condition of each patient.

Long-term disease-free survival after MIBG therapy for metastatic pheochromocytoma.

Pheochromocytomas are rare tumours originating in chromaffin cells, representing 0.1%-1% of all secondary hypertension cases. The majority are benign and unilateral, characterised by the production of catecholamines and other neuropeptides. Mainly located in the adrenal gland, they are more frequent between the third and fifth decades of life. Iodine-131 metaiodobenzylguanidine (131I-MIBG), a radiopharmaceutical agent used for scintigraphic localisation of pheochromocytomas, has been employed to treat malignant pheochromocytomas since 1983 in a few specialised centres around the world. We reviewed our clinical experience in one such case of a young lady who presented with history of abdominal pain, headache and lower back pain. On evaluation, ultrasonography revealed a right adrenal mass and elevated urine vanillylmandelic acid levels. Following surgical resection and histopathological confirmation of pheochromocytoma, MIBG scintigraphy revealed osseous metastases and hence, she underwent 131I-MIBG therapy.

Evaluation of the effectiveness of picosecond KTP and fractional thulium lasers on pigmented-type periorbital dark circles.

OBJECTIVE: To determine the effectiveness of picosecond KTP in reducing peri-ocular dark circles caused mainly by excessive pigmentation and to compare Picosecond KTP with Thulium laser ability in reducing the intensity and extent of peri-ocular dark circles. MATERIALS AND METHODS: This split-face prospective study included twelve women with periorbital dark circles (pigmented or mixed-pigmented type). The left lower eyelid was treated using the PicoHi machine (HIRONIC Ltd), a full beam Q-switched Nd-YAG provided by KTP crystal (523 nm) at settings of 0.3 J/cm2, 5 mm, 5 Hz, and 300 Ps. Whereas the right lower eyelid was treated using the Lavieen machine (WON TECH Co., Ltd), a fractional Thulium laser (1927 nm) at setting 1320 mJ/cm2, 30 × 15 mm, 1500 microseconds. Patients received a series of 3 treatment sessions, given at 4-week intervals. RESULTS: The 532-nm full beam Q-switched KTP and fractional Thulium lasers were more likely to induce post-inflammatory hyperpigmentation rather than decrease the pigmentation. The risk is higher with a Q-switched KTP laser, which may be attributed to the skin tone of the participants. Nonetheless, some improvement in the pigmented type of PDCs, although not detected clinically, was documented by the VISIA software. CONCLUSION: No solid conclusion can be drawn from the results of the study. Picosecond KTP and Thulium lasers may have a role in reducing PDCs yet more studies should be performed in order to determine the exact impact these lasers have.

Progression in low-intensity ultrasound-induced tumor radiosensitization.

BACKGROUND: Radiotherapy (RT) is a widely utilized tumor treatment approach, while a significant obstacle in this treatment modality is the radioresistance exhibited by tumor cells. To enhance the effectiveness of RT, scientists have explored radiosensitization approaches, including the use of radiosensitizers and physical stimuli. Nevertheless, several approaches have exhibited disappointing results including adverse effects and limited efficacy. A safer and more effective method of radiosensitization involves low-intensity ultrasound (LIUS), which selectively targets tumor tissue and enhances the efficacy of radiation therapy. METHODS: This review summarized the tumor radioresistance reasons and explored LIUS potential radiosensitization mechanisms. Moreover, it covered diverse LIUS application strategies in radiosensitization, including the use of LIUS alone, ultrasound-targeted intravascular microbubble destruction, ultrasound-mediated targeted radiosensitizers delivery, and sonodynamic therapy. Lastly, the review presented the limitations and prospects of employing LIUS-RT combined therapy in clinical settings, emphasizing the need to connect research findings with practical applications. RESULTS AND CONCLUSION: LIUS employs cost-effective equipment to foster tumor radiosensitization, curtail radiation exposure, and elevate the quality of life for patients. This efficacy is attributed to LIUS's ability to utilize thermal, cavitation, and mechanical effects to overcome tumor cell resistance to RT. Multiple experimental analyses have underscored the effectiveness of LIUS in inducing tumor radiosensitization using diverse strategies. While initial studies have shown promising results, conducting more comprehensive clinical trials is crucial to confirm its safety and effectiveness in real-world situations.

Gold nanoparticle-enhanced radiotherapy: Dependence of the macroscopic dose enhancement on the microscopic localization of the nanoparticles within the tumor vasculature.

In gold nanoparticle-enhanced radiotherapy, intravenously administered nanoparticles tend to accumulate in the tumor tissue by means of the so-called permeability and retention effect and upon irradiation with x-rays, the nanoparticles release a secondary electron field that increases the absorbed dose that would otherwise be obtained from the interaction of the x-rays with tissue alone. The concentration of the nanoparticles in the tumor, number of nanoparticles per unit of mass, which determines the total absorbed dose imparted, can be measured via magnetic resonance or computed tomography images, usually with a resolution of several millimeters. Using a tumor vasculature model with a resolution of 500 nm, we show that for a given concentration of nanoparticles, the dose enhancement that occurs upon irradiation with x-rays greatly depends on whether the nanoparticles are confined to the tumor vasculature or have already extravasated into the surrounding tumor tissue. We show that, compared to the reference irradiation with no nanoparticles present in the tumor model, irradiation with the nanoparticles confined to the tumor vasculature, either in the bloodstream or attached to the inner blood vessel walls, results in a two to three-fold increase in the absorbed dose to the whole tumor model, with respect to an irradiation when the nanoparticles have already extravasated into the tumor tissue. Therefore, it is not enough to measure the concentration of the nanoparticles in a tumor, but the location of the nanoparticles within each volume element of a tumor, be it inside the vasculature or the tumor tissue, needs to be determined as well if an accurate estimation of the resultant absorbed dose distribution, a key element in the success of a radiotherapy treatment, is to be made.

A randomised controlled trial of Standard Of Care versus RadioAblaTion in Early Stage HepatoCellular Carcinoma (SOCRATES HCC).

BACKGROUND: Therapeutic options for early-stage hepatocellular carcinoma (HCC) in individual patients can be limited by tumor and location, liver dysfunction and comorbidities. Many patients with early-stage HCC do not receive curative-intent therapies. Stereotactic ablative body radiotherapy (SABR) has emerged as an effective, non-invasive HCC treatment option, however, randomized evidence for SABR in the first line setting is lacking. METHODS: Trans-Tasman Radiation Oncology Group (TROG) 21.07 SOCRATES-HCC is a phase II, prospective, randomised trial comparing SABR to other current standard of care therapies for patients with a solitary HCC ≤ 8 cm, ineligible for surgical resection or transplantation. The study is divided into 2 cohorts. Cohort 1 will compromise 118 patients with tumors ≤ 3 cm eligible for thermal ablation randomly assigned (1:1 ratio) to thermal ablation or SABR. Cohort 2 will comprise 100 patients with tumors > 3 cm up to 8 cm in size, or tumors ≤ 3 cm ineligible for thermal ablation, randomly assigned (1:1 ratio) to SABR or best other standard of care therapy including transarterial therapies. The primary objective is to determine whether SABR results in superior freedom from local progression (FFLP) at 2 years compared to thermal ablation in cohort 1 and compared to best standard of care therapy in cohort 2. Secondary endpoints include progression free survival, overall survival, adverse events, patient reported outcomes and health economic analyses. DISCUSSION: The SOCRATES-HCC study will provide the first randomized, multicentre evaluation of the efficacy, safety and cost effectiveness of SABR versus other standard of care therapies in the first line treatment of unresectable, early-stage HCC. It is a broad, multicentre collaboration between hepatology, interventional radiology and radiation oncology groups around Australia, coordinated by TROG Cancer Research. TRIAL REGISTRATION: anzctr.org.au, ACTRN12621001444875, registered 21 October 2021.

Survival outcomes after breast cancer surgery among older women with early invasive breast cancer in England: population-based cohort study.

BACKGROUND: This study assessed the influence of age, co-morbidity and frailty on 5-year survival outcomes after breast conservation surgery (BCS) with radiotherapy (RT) versus mastectomy (with or without RT) in women with early invasive breast cancer. METHODS: Women aged over 50 years with early invasive breast cancer diagnosed in England (2014-2019) who had breast surgery were identified from Cancer Registry data. Survival estimates were calculated from a flexible parametric survival model. A competing risk approach was used for breast cancer-specific survival (BCSS). Standardized survival probabilities and cumulative incidence functions for breast cancer death were calculated for each treatment by age. RESULTS: Among 101 654 women, 72.2% received BCS + RT and 27.8% received mastectomy. Age, co-morbidity and frailty were associated with overall survival (OS), but only age and co-morbidity were associated with BCSS. Survival probabilities for OS were greater for BCS + RT (90.3%) versus mastectomy (87.0%), and the difference between treatments varied by age (50 years: 1.9% versus 80 years: 6.5%). Cumulative incidence functions for breast cancer death were higher after mastectomy (5.1%) versus BCS + RT (3.9%), but there was little change in the difference by age (50 years: 0.9% versus 80 years: 1.2%). The results highlight the change in baseline mortality risk by age for OS compared to the stable baseline for BCSS. CONCLUSION: For OS, the difference in survival probabilities for BCS + RT and mastectomy increased slightly with age. The difference in cumulative incidence functions for breast cancer death by surgery type was small regardless of age. Evidence on real-world survival outcomes among older populations with breast cancer is informative for treatment decision-making.

Might photobiomodulation therapy interfere with the frequency of severe mucositis and oral candidiasis? A retrospective analysis in patients with head and neck carcinoma.

PURPOSE: Considering the tumor in the oral cavity or the oropharynx and nasopharynx region might be an aggravating factor for oral mucositis (OM) manifestation, the present study aimed to evaluate whether the location of the tumor and the use of photobiomodulation therapy (PBMT) might affect the frequency of oral candidiasis (OC) during radiotherapy (RT) and/or chemotherapy (CT) treatments. METHODS: The medial records of seventy-four patients with head and neck cancer treated in a public service from 2016 to 2019 were evaluated. All these patients were submitted to RT in an accumulated dose of 48 to 70 Gy of radiation. Data about OM and OC were collected and presented according to the application of a therapeutic protocol with laser photobiomodulation (PBMT) to control oral mucositis, or not (No-PBM), and the location of tumor (head and neck or oral cavity). In the PBMT group patients, a low-power laser device composed of InGaAlP diode (maximum output power of 86.7 mW, active tip area of 0.1256 cm2, and continuous wavelength of 660 nm), was applied to the lips (three points each), right and left jugal mucosa (three points each), the limit between hard and soft palate (three points), buccal floor/sublingual gland (one point), lateral edge of the tongue (three points on each side), and back of the tongue (six points), three times weekly, for 5 weeks. The dosimetry used in each application was 2 J for 3 s, thus totaling 56 J. The correlation between clinical characteristics such as age, tumor size (T), metastatic lymph node (N), number of RT and CT sessions, candidiasis, and OM were analyzed. RESULTS: Mucositis grades 1 and 2 were the most common among all patients, especially before the 12th radiotherapy session, regardless of the treatment with PBM (p > 0.05). Additionally, no difference in the grade of OM and OC was significantly observed when comparing the two laser therapy groups. OC was more frequent after the 12th radiotherapy session in all groups. Nonetheless, OM and OC had a different correlation regarding to tumor location (head and neck and oral cavity) being PBMT a positive therapy to delay OM. It was observed a positive and statistically significant correlation between tumors at oral cavity and OM, regardless PBMT (R = 0.84, p < 0.05 to PBMT and R = 0.13, p < 0.05 to No-PBM). Otherwise, OC was positively correlated to local metastasis in patients with oral tumors undergoing PBMT (R = 0.84, p < 0.05). CONCLUSION: Patients with oral cavity tumor presented more OM, especially high grades, then patients with tumors in other regions of the head and neck, which seems to be related to the irradiation parameters of radiotherapy and/or with the limitation of conduction of PBMT in tumor areas. OM and OC were not changed by PBMT, although it helped to reduce the incidence of severe cases of OM.