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A synthetic approach has recently been developed which results in Cu(x)In(y)S2 quantum dots (QDs) possessing localized surface plasmon resonance (LSPR) modes in the near-infrared (NIR) frequencies.1 In this study, we investigate the potential benefits of near-field plasmonic effects centered upon light absorbing nanoparticles in a photovoltaic system by developing and verifying nonplasmonic counterparts as an experimental control. Simple QD-sensitized solar cells (QD-SSCs) were assembled which show an 11.5% relative increase in incident photon conversion efficiency (IPCE) achieved in the plasmon-enhanced devices. We attribute this increase in IPCE to augmented charge excitation stemming from near-field "antenna" effects in the plasmonic Cu(x)In(y)S2 QD-SSCs. This study represents the first of its kind; direct interrogation of the influence of plasmon-on-semiconductor architectures with respect to excitonic absorption in photovoltaic systems.
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PURPOSE: This study aims to review the current evidence on the utility of stereotactic body radiation therapy (SBRT), with or without transarterial chemoembolization (TACE), for early-stage hepatocellular carcinoma (ESHCC) patients not amenable to standard curative treatment options. METHODS: Literature search was conducted using PubMed, ScienceDirect, and Google Scholar. Comparative studies reporting oncologic outcomes were included in the review. RESULTS: Five studies (one phase II randomized controlled trial, one prospective cohort, three retrospective studies) compared SBRT versus TACE. Pooled analysis showed an overall survival (OS) benefit after 3 years (OR 1.65, 95% CI 1.17-2.34, p = 0.005) which persisted in the 5-year data (OR 1.53, 95% CI 1.06-2.22, p = 0.02) in favor of SBRT. RFS benefit with SBRT was also seen at 3 years (OR 2.06, 95% CI 1.03-4.11, p = 0.04) which continued after 5 years (OR 2.35, 95% CI 1.47-3.75, p = 0.0004). Pooled 2-year local control (LC) favored SBRT over TACE (OR 2.96, 95% CI 1.89-4.63, p < 0.00001). Two retrospective studies compared TACE + SBRT versus TACE alone. Pooled analysis showed significantly improved 3-year OS (OR 5.47; 95% CI 2.47-12.11, p < 0.0001) and LC (OR: 21.05; 95% CI 5.01-88.39, p ≤ 0.0001) in favor of the TACE + SBRT group. A phase III study showed significantly improved LC and PFS with SBRT after failed TACE/TAE versus further TACE/TAE. CONCLUSIONS: Taking into account the limitations of the included studies, our review suggests significantly improved clinical outcomes in all groups having SBRT as a component of treatment versus TACE alone or further TACE. Larger prospective studies are warranted to further define the role of SBRT and TACE for ESHCC.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Radiocirurgia , Humanos , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Radiocirurgia/efeitos adversos , Estudos Retrospectivos , Estudos Prospectivos , Terapia Combinada , Resultado do TratamentoRESUMO
PURPOSE: The study reports on the current perception of medical and radiation oncologists regarding teleconsultation in the Philippines. Before the COVID-19 pandemic, the adoption of telemedicine was not widespread. With movement restrictions imposed during the pandemic, physicians were compelled to use telemedicine. It is uncertain whether physicians will still adopt its use in practice in the post-COVID-19 era. This study gives insight into the possible adaptation of this mode of consultation in the future, especially in areas with limited health care resources. MATERIALS AND METHODS: We conducted a national survey among medical oncologists and radiation oncologists in the Philippines. A 43-item online survey was developed, validated, and administered to the oncologists. The demographics and data from categorical questions were reported as frequencies and percentages. RESULTS: A total of 142 responses were gathered from 82 medical oncologists and 60 radiation oncologists. There was agreement among participants that, during the pandemic, teleconsultation could be used for the first visit, diagnostic workup request, treatment explanation, follow-up care, and chronic disease management. There was disagreement whether cancer diagnosis disclosure and cancer prognosis revelation could be performed via teleconsultation, and there was agreement that emergency consultation and physical examination would warrant a face-to-face consultation. After the COVID-19 pandemic, 78.7% intend to continue using teleconsultation except for emergency consultations, first visits, physical examination, diagnosis disclosure, and cancer prognosis revelation. CONCLUSION: Teleconsultation was perceived by oncologists as an acceptable method of providing cancer care during and after the COVID-19 pandemic. Oncologists also intend to use teleconsultation in the post-COVID-19 era in certain aspects of patient care.
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COVID-19 , Consulta Remota , Humanos , COVID-19/epidemiologia , Consulta Remota/métodos , Radio-Oncologistas , Pandemias , Filipinas/epidemiologiaRESUMO
Purpose: To report technical details and 15-month outcomes of a patient with node-positive external auditory canal (EAC) squamous cell carcinoma (SCC) treated with definitive intracavitary high-dose-rate (HDR) brachytherapy to primary tumor, and external beam radiotherapy (EBRT) to draining lymphatics. Material and methods: A 21-year-old male was diagnosed with SCC of the right EAC. The patient underwent definitive HDR intracavitary brachytherapy, 340 cGy/fraction for 14 twice-daily fractions, followed by EBRT using intensity-modulated radiation therapy (IMRT) to cover the grossly enlarged pre-auricular node, ipsilateral intra-parotid, and cervical lymph node levels II and III. Results: The approved brachytherapy plan had an average high-risk clinical tumor volume (CTV-HR) D90 of 341 cGy with a total dose of 47.7 Gy (BED, 80.3 Gy, EQD2, 66.6 Gy). For the approved IMRT plan, the prescription to the involved right pre-auricular node was 66 Gy in 33 fractions, and more than 95% of the target received at least 62.7 Gy. High-risk nodal regions were simultaneously prescribed: 59.4 Gy in 1.8 Gy fractions, and more than 95% received at least 56.4 Gy. Organs at risk (OARs) were kept below their dose constraints.The patient tolerated both the procedures with no grade ≥ 2 treatment-related adverse events. Grade 1 dermatitis in the right pre-auricular and cervical areas during the course of EBRT was experienced. Fifteen months post-RT, the patient has no evidence of disease, and was noted to have EAC stenosis, which translated to moderate conductive hearing loss of the right ear. Thyroid function was normal at 15 months after EBRT. Conclusions: This case report illustrates that the delivered definitive radiotherapy is technically feasible, effective, and well-tolerated in patients with SCC of EAC.
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Purpose: The aim of the study was to evaluate the safety and clinical outcomes of single application multi-fractionated computed tomography (CT)-guided interstitial high-dose-rate brachytherapy given in four fractions in locally advanced cervical cancer. Material and methods: Patients with locally advanced cervical cancer stage IIB-IVA treated definitively with external radiation ± weekly cisplatin, followed by single application multi-fractionated CT-guided interstitial high-dose-rate brachytherapy in four fractions were included. Dosimetry data, clinical response, and toxicity records were reviewed. Results: Between January 2018 and December 2022, twenty-two patients were included. Clinical stage distribution was as follows: IIB - 13.6%, IIIB - 27.3%, IIIC - 22.7%, and IVA - 36.4%. Mean high-risk clinical target volume (HR-CTV) was 66.19 ±32.69 cm3, and HR-CTV D90 dose was 86.8 ±1.7 Gy. 2 cc doses to bladder, rectum, and sigmoid were 84.6 ±2.8 Gy, 71.5 ±2.4 Gy, and 65.6 ±4.0 Gy, respectively. Mean overall treatment time was 66 ±21 days. With a median follow-up of 11.5 months (range, 5-44 months), median survival and local control were not achieved. One-year local control rate, one-year progression-free survival, and one-year overall survival were 82%, 66%, and 78%, respectively. Univariate analysis showed overall treatment time to be the only variable associated with all oncologic outcomes. For acute toxicity, grade 3 toxicity in four patients and grade 4 toxicity of infection in one patient were observed. For late toxicity, grade 3 gastrointestinal toxicity was noted in two patients. Conclusions: Initial results suggest that single application multi-fractionated CT-guided interstitial brachytherapy given in four fractions in locally advanced cervical cancer seems to be feasible and safe, but additional evidence is needed to generate more validated conclusions.
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PURPOSE: The aim of this case report is to present a case of orbital mesenchymal chondrosarcoma sarcoma with multiple recurrences, and to report technical details of a contemporary approach for orbital brachytherapy that can be used in low-resource settings. MATERIAL AND METHODS: A 46-year-old female diagnosed with recurrent orbital mesenchymal chondrosarcoma of the left orbit presented with her third local recurrence. The patient proceeded with conservative surgery with planned adjuvant high-dose-rate brachytherapy 2 weeks post-surgery. Brachytherapy mold applicator was fabricated using thermoplastic mask, ProGuide catheter needles, catheter fixation buttons, and a strip of gauze. Ideal catheter placement was done with CT simulation planning. RESULTS: High-risk clinical target volume (HR-CTV) corresponded to gross tumor residual, and intermediate-risk clinical target volume (IR-CTV) corresponded to the whole orbit. Flexitron iridium-192 high-dose-rate (HDR) brachytherapy plan was generated using Oncentra brachytherapy planning system. The treatment plan had HR-CTV total dose of 55.6 Gy and equivalent dose in 2 Gray fractions (EQD2) of 96 Gy. IR-CTV total dose was 45.5 Gy and EQD2 of 70 Gy. The plan was evaluated using dose-volume histogram and dosimetric parameters, which showed adequate irradiation of tumor volume and at-risk areas. The patient underwent orbital brachytherapy without any adverse events, except for mild skin erythema. One-year post-treatment showed no local recurrence and no soft tissue necrosis or swelling. CONCLUSIONS: In the previously irradiated orbital sarcoma patient, adjuvant brachytherapy is an effective and safe modality for the delivery of sufficient radiation dose to the target, as presented in the current case report. The materials used in the brachytherapy applicator are easily available in majority of radiation therapy centers and can be manufactured even in low-resource settings.