Atomistic nonlinear carrier dynamics in Ge.

An atomistic technique to successfully demonstrate the ultrafast carrier dynamics in Ge photoconductive samples is reported here. The technique is validated against the experimental findings and with the Drude conductivities. The impact of the various different scattering mechanisms is used to calibrate the experimental results. It is observed that the total scattering rate is not a constant parameter as contrast to Drude model which uses constant scattering rate as the fitting parameter to demonstrate the ultrafast carrier dynamics, but strongly dependent on the applied peak THz field strength. It also contradicts with the relaxation time approximation (RTA) method which uses scattering rate chosen on the empirical basis as the fitting parameter to demonstrate the ultrafast carrier dynamics. On the other hand the limitations and challenges offered by various types of density functional theories (DFT) pose lot of challenges. In current manuscript various types of scattering mechanisms i.e. acoustic, intervalley, Coulomb and impact ionization on the behavior of carrier conductivity are studied in details. The proposed technique has shown capability to extract low and high frequency conductivities accurately which is impossible through the Drude model or DFT based theories. It is observed that the free carrier absorption coefficient depends on the refractive index of the material at low THz frequencies. The solution of Boltzmann transport equation through Monte Carlo technique provides valuable insights for better understanding of ultrafast carrier transportation mechanism. The free carrier absorption spectra are found to be in good agreement with the experimental results at various THz field strengths.

In-vivo Comparison of Planned and Measured Rectal Doses during Cobalt-60 HDR CT-based Intracavitary Brachytherapy Applications of Cervical Cancer Using the PTW 9112 Semiconductor Probe.

BACKGROUND: A semiconductor rectal probe was used to compare planned and measured rectal doses during Co-60 high dose rate (HDR) CT-based intracavitary brachytherapy applications (ICBT) of cervical cancer. MATERIALS AND METHODS: A total of 22 HDR brachytherapy applications were included from 11 patients who were first treated with EBRT to the whole pelvis with a total prescribed dose of 50 Gy in 25 fractions. During each application, a PTW 9112 probe rectal probe having a series of five semiconductor diodes (R1 to R5) was inserted into the patient's rectum and a CT-based HDR ICBT application with a prescribed dose per fraction of 7 or 7.5 Gy to HRCTV was performed. Measurements were carried in water phantom using PTW rectal and universal adaptor plugs. Doses measured in phantom and with patients were compared to those calculated by the treatment planning system. RESULTS: The mean percentage dose difference ΔD (%) between calculated and measured values from phantom study were -5.29%, 1.89%, -2.72%, -4.76, and 0.72% for R1, R2, R3, R4, and R3 diodes, respectively and the overall mean ΔD (%) value with standard deviation (SD) was -2.03%±9.6%. From the patient study, a ΔD (%) that ranged from -19.5% to 24.0%, which corresponded to dose disparities between -0.77 Gy and 0.66 Gy. The median ΔD (%) ranged from 0.4% to 1.3%, or -0.03 to 0.05 Gy, respectively. ΔD (%) values exceeded 10% in approximately 26.4% of measurements (29 out of 110 in 22 applications). The location of Rmax in computed and measured values differs in 5 of 22 applications might be due to possible displacement of rectal probe between simulation and treatment. CONCLUSION: Despite the likely geometrical shift of measuring detectors between insertion and treatment, in-vivo dosimetry is feasible and can be used to estimate the dose to the rectum during HDR ICBT.

Expression analysis and function of mitochondrial genome-encoded microRNAs.

MicroRNAs (miRNAs) play a significant role in nuclear and mitochondrial anterograde and retrograde signaling. Most of the miRNAs found inside mitochondria are encoded in the nuclear genome, with a few mitochondrial genome-encoded non-coding RNAs having been reported. In this study, we have identified 13 mitochondrial genome-encoded microRNAs (mitomiRs), which were differentially expressed in breast cancer cell lines (MCF-7, MDA-MB-468 and MDA-MB-231), non-malignant breast epithelial cell line (MCF-10A), and normal and breast cancer tissue specimens. We found that mitochondrial DNA (mtDNA) depletion and inhibition of mitochondrial transcription led to reduced expression of mitomiRs in breast cancer cells. MitomiRs physically interacted with Ago2, an RNA-induced silencing complex (RISC) protein, in the cytoplasm and inside mitochondria. MitomiRs regulate the expression of both nuclear and mitochondrial transcripts in breast cancer cells. We showed that mitomiR-5 targets the PPARGC1A gene and regulates mtDNA copy number in breast cancer cells. MitomiRs identified in the present study may be a promising tool for expression and functional analysis in patients with a defective mitochondrial phenotype, including cancer and metabolic syndromes. This article has an associated First Person interview with the first author of the paper.

Health-related quality of life among oral and oropharyngeal cancer patients: An exploratory study.

OBJECTIVES: To comprehensively explore the effect of several sociodemographic-, patient- and tumour-related factors on the health-related quality of life (HRQoL) of oral and oropharyngeal cancer patients. METHODOLOGY: Patients diagnosed with oral and oropharyngeal cancers were included in the present cross-sectional study. Information pertaining to various sociodemographic-, patient- and tumour-related factors was recorded. HRQoL was assessed using standard 12-item Short Form Health Survey version 2 (SF12V2), and oral health-related quality of life (OHRQoL) was assessed by Oral Health Impact Profile-14 (OHIP). RESULTS: A total of 108 patients participated in the present study. Results revealed that nodal metastasis, histological differentiation and pain were significant predictors of OHRQoL, while site, size, stage, histological differentiation and pain were significant predictors of HRQoL. Pain was the single most significant negative determinant of HRQoL that was associated with worst total OHIP (B = 2.01, ß = 0.45, p < .0001), physical (B = -0.88, ß = -0.21, p = .017) and mental (B = -1.00, ß = -0.22, p = .016) component summary scores. CONCLUSIONS: Number of sociodemographic-, patient- and tumour-related factors emerged as significant predictors of HRQoL and OHRQoL. Study results might help in formulating targeted treatment plan, optimising patient care and follow-up.

Relationship between physical activity, objective sleep parameters, and circadian rhythm in patients with head and neck cancer receiving chemoradiotherapy: A longitudinal study.

OBJECTIVES: This study was developed to assess the relationship between physical activity, sleep and circadian rhythm using accelerometer and urine melatonin levels in patients with head and neck cancer (HNC). Also, this study evaluated the changes in physical activity, sleep, and circadian rhythm during the seven-week course of chemoradiotherapy. METHODS: This longitudinal study recruited 27 participants diagnosed with HNC who were planning to undergo chemoradiotherapy. Accelerometers worn for 3 days during the 1st, 3rd, and 7th weeks of chemoradiotherapy were used to assess physical activity levels (step count and metabolic equivalents [METs]) and sleep quality (total sleep time [TST], sleep onset latency [SOL], and sleep efficiency [SE]). Urine melatonin analysis was conducted using the morning void urine sample on 1st, 3rd, and 7th weeks. The change in variables during the seven weeks and the correlation between them were analyzed. RESULTS: During the seven weeks, trends of reduction in variables of physical activity, sleep and circadian rhythm were observed with significant decrease in step count, TST and melatonin levels. SE was found to have strong negative correlation with physical activity. TST was found to have moderate correlation with SE and step count. The variables of physical activity also showed moderate correlation among them. CONCLUSION: This study concludes that higher physical activity is associated with poor SE due to increased night-time activity. There was a significant reduction in physical activity and sleep observed during seven weeks with moderate association between them. The significant circadian rhythm deregulation however showed poor association with the other variables.Level of Evidence: 2b.

LiverNet: efficient and robust deep learning model for automatic diagnosis of sub-types of liver hepatocellular carcinoma cancer from H&E stained liver histopathology images.

PURPOSE: Liver cancer is one of the most common types of cancers in Asia with a high mortality rate. A common method for liver cancer diagnosis is the manual examination of histopathology images. Due to its laborious nature, we focus on alternate deep learning methods for automatic diagnosis, providing significant advantages over manual methods. In this paper, we propose a novel deep learning framework to perform multi-class cancer classification of liver hepatocellular carcinoma (HCC) tumor histopathology images which shows improvements in inference speed and classification quality over other competitive methods. METHOD: The BreastNet architecture proposed by Togacar et al. shows great promise in using convolutional block attention modules (CBAM) for effective cancer classification in H&E stained breast histopathology images. As part of our experiments with this framework, we have studied the addition of atrous spatial pyramid pooling (ASPP) blocks to effectively capture multi-scale features in H&E stained liver histopathology data. We classify liver histopathology data into four classes, namely the non-cancerous class, low sub-type liver HCC tumor, medium sub-type liver HCC tumor, and high sub-type liver HCC tumor. To prove the robustness and efficacy of our models, we have shown results for two liver histopathology datasets-a novel KMC dataset and the TCGA dataset. RESULTS: Our proposed architecture outperforms state-of-the-art architectures for multi-class cancer classification of HCC histopathology images, not just in terms of quality of classification, but also in computational efficiency on the novel proposed KMC liver data and the publicly available TCGA-LIHC dataset. We have considered precision, recall, F1-score, intersection over union (IoU), accuracy, number of parameters, and FLOPs as metrics for comparison. The results of our meticulous experiments have shown improved classification performance along with added efficiency. LiverNet has been observed to outperform all other frameworks in all metrics under comparison with an approximate improvement of [Formula: see text] in accuracy and F1-score on the KMC and TCGA-LIHC datasets. CONCLUSION: To the best of our knowledge, our work is among the first to provide concrete proof and demonstrate results for a successful deep learning architecture to handle multi-class HCC histopathology image classification among various sub-types of liver HCC tumor. Our method shows a high accuracy of [Formula: see text] on the proposed KMC liver dataset requiring only 0.5739 million parameters and 1.1934 million floating point operations per second.

Fabrication and development of a thorax phantom to evaluate 3D CRT treatment planning techniques for post-mastectomy chest wall radiotherapy.

The aim of this study was to design and fabricate a thorax phantom to quantify the radiation doses to the region of the chest wall (with 3 ionization chambers), the organ at risk (OAR) (lung), and the surface using radiochromic films (EBT3) for three different 3D CRT treatment planning techniques. Anthropomorphic phantoms are one of the best tools for verifying the quality of the radiotherapy treatment plans generated by treatment planning systems since they can provide equivalent human tissue densities. Thirty acrylic plates were cut into ellipses 21 cm in height and 31 cm in width, and slots were created to insert lung equivalent cork material and bone equivalent Teflon material. Three treatment planning techniques were designed: (A) tangential pair beams, (B) tangential pair beams with wedges and (C) tangential beams followed by an anterior oblique beam. The percentage difference between the measured point doses and the calculated doses (measured with three CC13 ionization chambers) ranged from - 3.2 to 1.6%, with a mean deviation of - 1.04 ± 1.3%. The measured mean percentage doses on the target surface with EBT3 film were 90.3% and 95.1% of the prescribed dose with 5-mm and 10-mm boluses, respectively. Finally, the average absolute dose difference between the measured and calculated surface doses was within 10 cGy in all three planning techniques. The developed thorax phantom is suitable for point dose measurements using ionization chambers and for surface dose measurements using EBT3 Gafchromic films in post-mastectomy chest wall radiotherapy.

Effect of domperidone, ondansetron, olanzapine-containing antiemetic regimen on QTC interval in patients with malignancy: a prospective, observational, single-group, assessor-blinded study.

Domperidone, ondansetron and olanzapine can prolong the QT interval. The clinical use of combinations of these drugs is not uncommon. Our study aimed to determine the presence of any QTc prolonging effect of the combination when used as antiemetic in patients receiving cancer chemotherapy. We carried out a prospective, observational study of patients with malignancy who were to receive domperidone, ondansetron and olanzapine-containing antiemetic regimen. Electrocardiograms were recorded before and during the administration of antiemetics, for three consecutive days. A blinded assessor determined the QTc interval using Bazett and Fridericia formulae. Thirty-six patients completed the study; 23 (63.9%) were females. There was a statistically significant change in QTc with time (Fridericia, χ2(4) = 15.629, p = 0.004; Bazett, χ2(4) = 15.910, p = 0.003); QTc on Day 1 was more than that during baseline (p < 0.001); these differences were significant in females (Fridericia, χ2(4) = 13.753, p = 0.008; Bazett, χ2 (4) = 13.278, p = 0.010) but not in males (Fridericia, χ2 (4) = 4.419, p = 0.352; Bazett, χ2(4) = 4.280, p = 0.369). Two female patients had an absolute QTc prolongation (Bazett correction) of > 500 ms. However, no clinically significant adverse events occurred. The findings show that QTc prolongation is a concern with olanzapine alone and in combination with domperidone and ondansetron, and needs to be investigated further.

Surface Dose Measurements in Chest Wall Postmastectomy Radiotherapy to Achieve Optimal Dose Delivery with 6 MV Photon Beam.

Aim: A tissue-equivalent bolus of sufficient thickness is used to overcome build up effect to the chest wall region of postmastectomy radiotherapy (PMRT) patients with tangential technique till Radiation Therapy Oncology Group (RTOG) Grade 2 (dry desquamation) skin reaction is observed. The aim of this study is to optimize surface dose delivered to chest wall in three-dimensional radiotherapy using EBT3 film. Materials and Methods: Measurements were conducted with calibrated EBT3 films with thorax phantom under "open beam, Superflab gel (0.5 cm) and brass bolus conditions to check correlation against TPS planned doses. Eighty-two patients who received 50 Gy in 25# were randomly assigned to Group A (Superflab 0.5 cm gel bolus for first 15 fractions followed by no bolus in remaining 10 fractions), Group B or Group C (Superflab 0.5 cm gel or single layer brass bolus, respectively, till reaching RTOG Grade 2 skin toxicity). Results: Phantom measured and TPS calculated surface doses were within - 5.5%, 4.7%, and 8.6% under open beam, 0.5 cm gel, and single layer of brass bolus applications, respectively. The overall surface doses (OSD) were 80.1% ±2.9% (n = 28), 92.6% ±4.6% (n = 28), and 87.4% ±4.7% (n = 26) in Group A, B, and C, respectively. At the end of treatment, 7 out of 28; 13 out of 28; and 9 out of 26 patients developed Grade 2 skin toxicity having the OSD value of 83.0% ±1.6% (n = 7); 93.7% ±3.2% (n = 13); and 89.9% ±5.6% (n = 9) in Groups A, B, and C, respectively. At the 20th-23rd fraction, 2 out of 7; 6 out of 13; and 4 out of 9 patients in Groups A, B, and C developed a Grade 2 skin toxicity, while the remaining patients in each group developed at the end of treatment. Conclusions: Our objective to estimate the occurrence of optimal dose limit for bolus applications in PMRT could be achieved using clinical EBT3 film dosimetry. This study ensured correct dose to scar area to protect cosmetic effects. This may also serve as quality assurance on optimal dose delivery for expected local control in these patients.

Randomized control trial evidence for the benefits of massage and relaxation therapy on sleep in cancer survivors-a systematic review.

PURPOSE: Cancer survivors may experience sleep disturbances during and after their cancer treatments. While pharmacological approaches are commonly used to address sleep disturbances, they may have a number of adverse effects. This review studied the effect of two non-pharmacological interventions (massage and relaxation therapy) on sleep disturbances in cancer survivors. METHODS: A search for randomised controlled trials (RCTs) was conducted on PubMed, Scopus, Web of Science, PEDro, and CINAHL using relevant keywords. RESULTS: The search yielded 371 articles, with 4 RCTs studying massage therapy and 3 RCTs studying relaxation therapy included for qualitative analysis. Massage therapy studies showed statistically significant improvement in self-reported sleep questionnaires and objectively recorded long sleep episodes, as assessed via an accelerometer. No significant improvements in sleep outcomes were observed in the relaxation therapy studies, although there were trends for improved self-reported sleep quality. CONCLUSION: While massage therapy provided by massage therapists may have some potential for improving sleep outcomes for cancer survivors, there is no such current evidence regarding relaxation therapy. IMPLICATIONS FOR CANCER SURVIVORS: Cancer survivors who experience sleep disturbances may benefit from regular sessions with a massage therapist. However, future studies should examine the long-term feasibility of massage therapist-delivered services, particularly for cancer survivors with limited finances, and determine if benefits can be obtained if massage is provided by non-certified individuals. Relaxation therapy appears to be safe for cancer survivors, but future RCTs involving larger sample sizes need to be conducted to better determine its feasibility and efficacy.

Simultaneous Measurement of In vivo and Transit Mid-Plane Doses with Ionization Chambers in Gynecological Malignancy Patients Undergoing Three-Dimensional Conformal Radiotherapy.

PURPOSE: The aim of this study is to estimate delivered radiation doses inside planning tumor volume (PTV) using the in vivo (mid-plane dose) measurement and transit measurement methods in gynecological malignancy patients undergoing three-dimensional conformal radiotherapy (3DCRT) using calibrated ionization chambers. MATERIALS AND METHODS: Six patients with histopathologically proven carcinoma of the cervix or endometrium were planned with four-field 3DCRT to the pelvic site. Isocenter was at the geometric mid-plane of PTV with a dose prescription of 50 Gy in 25 fractions. Clinical mid-plane dose (D iso, Transit) estimates were done in one method (transit) using the FC-65 positioned at electronic portal imaging device level. In another method, a repeat computerized tomography scan was performed (at the 11th fraction) using CC-13 having a protective cap in the vaginal cavity for in vivo measurements (D in vivo ). Simultaneous measurements were performed with the two chambers from the 11th fraction onward at least 3-4 times during the remaining course of treatment. RESULTS: The agreement of mean doses from these two described methods and treatment planning system reference doses was in the range of -4.4 ± 1.1% (minimum) to -0.3 ± 2.0% (maximum) and -4.0 ± 1.7% (minimum) to 1.9 ± 2.4% for D in vivo and D iso, Transit , respectively, which are an acceptable range of daily radiation dose delivery. CONCLUSION: The fundamental importance of this study lies in simultaneous validation of delivered dose in real time with two methods. A study in this small number of patients has given the confidence to apply transit measurements for quality assurance on a routine basis as an accepted clinical dosimetry for the selected patients.

Influence of Air Gap under Bolus in the Dosimetry of a Clinical 6 MV Photon Beam.

AIM: In some situations of radiotherapy treatments requiring application of tissue-equivalent bolus material (e.g., gel bolus), due to material's rigid/semi-rigid nature, undesirable air gaps may occur beneath it because of irregularity of body surface. The purpose of this study was to evaluate the dosimetric parameters such as surface dose (Ds), depth of dose maximum (dmax), and depth dose along central axis derived from the percentage depth dose (PDD) curve of a 6 MV clinical photon beam in the presence of air gaps between the gel bolus and the treatment surface. MATERIALS AND METHODS: A bolus holder was designed to hold the gel bolus sheet to create an air gap between the bolus and the radiation field analyzer's (RFA-300) water surface. PDD curves were taken for field sizes of 5 cm × 5 cm, 10 cm × 10 cm, 15 cm × 15 cm, 20 cm × 20 cm, and 25 cm × 25 cm, with different thicknesses of gel bolus (0.5, 1.0, and 1.5 cm) and air gap (from 0.0 to 3.0 cm), using a compact ionization chamber (CC13) with RFA-300 keeping 100 cm source-to-surface (water) distance. The dosimetric parameters, for example, "Ds," "dmax," and difference of PDD (maximum air gap vs. nil air gap), were analyzed from the obtained PDD curves. RESULTS: Compared to ideal conditions of full contact of bolus with water surface, it has been found that there is a reduction in "Ds" ranging from 14.8% to 3.2%, 14.9% to 1.1%, and 12.6% to 0.7% with the increase of field size for 0.5, 1.0, and 1.5 cm thickness of gel boluses, respectively, for maximum air gap. The "dmax" shows a trend of moving away from the treatment surface, and the maximum shift was observed for smaller field size with thicker bolus and greater air gap. The effect of air gap on PDD is minimal (≤1%) beyond 0.4 cm depth for all bolus thicknesses and field sizes except for 5 cm × 5 cm with 1.5 cm bolus thickness. CONCLUSIONS: The measured data can be used to predict the probable effect on therapeutic outcome due to the presence of inevitable air gaps between the bolus and the treatment surface.

Drug-drug interactions in patients undergoing chemoradiotherapy and the impact of an expert team intervention.

Background Several studies have examined the drug-drug interaction patterns in different patient populations and treatment settings; however, there is a need, particularly in the field of oncology and radiotherapy, for evaluating methods targeted towards preventing potential drug-drug interactions. One of the measures proposed is identifying potential interactions using computer programs and their evaluation by pharmacologists or clinical pharmacists, thereby providing clinically relevant information to the treating physician regarding the required prescription changes. Objective To determine the prevalence of potential drug-drug interactions in patients receiving chemoradiotherapy and assess the usefulness of expert team recommendations in minimizing interactions. Setting Patients admitted to the radiotherapy and oncology ward of a tertiary care teaching hospital in Karnataka, India. Method We conducted a prospective, cross-sectional study of prescriptions written for patients receiving chemoradiotherapy. Prescriptions containing two or more drugs, at least one of the drugs being an anticancer drug, were analyzed. They were screened for potential drug-drug interactions using the Lexicomp® drug interaction software. The interactions were classified as X, drug combination to be avoided; D, modification of therapy to be considered; and C, therapy to be monitored, as per the Lexicomp criteria. Main outcome measure The number of drug-drug interactions detected that were accepted by the treating radio-oncologist as requiring prescription change before and after the prescription review by an expert team. Results Two hundred twenty-three prescriptions were screened for the presence of drug-drug interactions; 106 prescriptions (47.53%) containing 620 drugs and 211 drug-drug interactions were identified. Of the 211 interactions identified, 6.64% (14/211), 18.48% (39/211), and 74.88% (158/211) drug-drug interactions belonged to category X, D, and C, respectively. Twenty-seven (50.94%) of the 53 category X and D interactions identified were accepted the oncologist as requiring a change in the prescription; an additional 13 (24.53%) interactions were identified as significant by the expert team, and 11 (84.62%) of these were accepted by the oncologist. Conclusion A system of alerting the treating physician to a potential drug-drug interaction leads to avoidance of prescription of the interacting drug combination, and the assistance by an expert team adds significantly to avoidance of clinically relevant drug interactions.

Surveillance for pancreatic cancer in high-risk individuals.

Background: Surveillance of individuals at high risk of pancreatic ductal adenocarcinoma (PDAC) and its precursors might lead to better outcomes. The aim of this study was to determine the prevalence and outcomes of PDAC and high-risk neoplastic precursor lesions among such patients participating in surveillance programmes. Methods: A multicentre study was conducted through the International CAncer of the Pancreas Screening (CAPS) Consortium Registry to identify high-risk individuals who had undergone pancreatic resection or progressed to advanced PDAC while under surveillance. High-risk neoplastic precursor lesions were defined as: pancreatic intraepithelial neoplasia (PanIN) 3, intraductal papillary mucinous neoplasia (IPMN) with high-grade dysplasia, and pancreatic neuroendocrine tumours at least 2 cm in diameter. Results: Of 76 high-risk individuals identified in 11 surveillance programmes, 71 had undergone surgery and five had been diagnosed with inoperable PDAC. Of the 71 patients who underwent resection, 32 (45 per cent) had PDAC or a high-risk precursor (19 PDAC, 4 main-duct IPMN, 4 branch-duct IPMN, 5 PanIN-3); the other 39 patients had lesions thought to be associated with a lower risk of neoplastic progression. Age at least 65 years, female sex, carriage of a gene mutation and location of a lesion in the head/uncinate region were associated with high-risk precursor lesions or PDAC. The survival of high-risk individuals with low-risk neoplastic lesions did not differ from that in those with high-risk precursor lesions. Survival was worse among patients with PDAC. There was no surgery-related mortality. Conclusion: A high proportion of high-risk individuals who had surgical resection for screening- or surveillance-detected pancreatic lesions had a high-risk neoplastic precursor lesion or PDAC at the time of surgery. Survival was better in high-risk individuals who had either low- or high-risk neoplastic precursor lesions compared with that in patients who developed PDAC.

Antecedentes: Se podrían obtener mejores resultados con el seguimiento de individuos de alto riesgo para adenocarcinoma ductal pancreático (pancreatic ductal adenocarcinoma, PDAC) y lesiones precursoras. El objetivo de este estudio fue determinar la prevalencia y los resultados del PDAC y de las lesiones precursoras de alto riesgo neoplásico en pacientes que participaron en programas de seguimiento. Métodos: Se llevó a cabo un estudio multicéntrico a través del registro internacional del consorcio CAPS (Common Automotive Platform Standard) para identificar a las personas de alto riesgo que se habían sometido a una resección pancreática o habían progresado a PDAC avanzado mientras estaban en seguimiento. Se definieron como lesiones neoplásicas precursoras de alto riesgo la neoplasia intraepitelial pancreática de tipo 3 (PanIN­3), la neoplasia papilar mucinosa intraductal (intraductal papillary mucinous neoplasia, IPMN) con displasia de alto grado y los tumores neuroendocrinos pancreáticos (pancreatic neuroendocrine tumours, PanNET) de ≥ 2 cm de diámetro. Resultados: De 76 individuos con lesiones de alto riesgo identificados en 11 programas de seguimiento, 71 fueron tratados quirúrgicamente y 5 fueron diagnosticados de un PDAC inoperable. De las 71 resecciones, 32 (45%) tenían PDAC o una lesión precursora de alto riesgo (19 PDAC, 4 IPMN de conducto principal, 4 IPMN de rama secundaria y 5 PanIN­3). Los otros 39 pacientes tenían lesiones que se consideraron asociadas con un menor riesgo de progresión neoplásica. La edad ≥ 65 años, el sexo femenino, el ser portador de una mutación genética y la localización de la lesión en la cabeza/proceso uncinado fueron factores asociados a las lesiones precursoras de alto riesgo o al PDAC. No hubo diferencias en la supervivencia de individuos de alto riesgo con lesiones neoplásicas de bajo riesgo frente a aquellos que presentaron lesiones precursoras de alto riesgo. La supervivencia fue peor en los pacientes con PDAC. No hubo mortalidad relacionada con la cirugía. Conclusión: Un elevado porcentaje de individuos de alto riesgo que se sometieron a resección quirúrgica tras la detección de lesiones pancreáticas en el seguimiento tenían una lesión precursora neoplásica de alto riesgo o un PDAC. La supervivencia fue mejor en individuos de alto riesgo que tenían lesiones precursoras neoplásicas de bajo o alto riesgo en comparación con aquellos pacientes que habían desarrollado un PDAC.

Clinical implementation of brass mesh bolus for chest wall postmastectomy radiotherapy and film dosimetry for surface dose estimates.

OBJECTIVE: This study presents the dosimetric data taken with radiochromic EBT3 film with brass mesh bolus using solid water and semi-breast phantoms, and its clinical implementation to analyze the surface dose estimates to the chest wall in postmastectomy radiotherapy (PMRT) patients. MATERIALS AND METHODS: Water-equivalent thickness of brass bolus was estimated with solid water phantom under 6 megavoltage photon beam. Following measurements with film were taken with no bolus, 1, 2, and 3 layers of brass bolus: (a) surface doses on solid water phantom with normal incidence and on curved surface of a locally fabricated cylindrical semi-breast phantom for tangential field irradiation, (b) depth doses (in solid phantom), and (c) surface dose measurements around the scar area in six patients undergoing PMRT with prescribed dose of 50 Gy in 25 fractions. RESULTS: Water-equivalent thickness (per layer) of brass bolus 2.09 ± 0.13 mm was calculated. Surface dose measured by film under the bolus with solid water phantom increased from 25.2% ±0.9% without bolus to 62.5% ± 3.1%, 80.1% ± 1.5%, and 104.4% ± 1.7% with 1, 2, and 3 layers of bolus, respectively. Corresponding observations with semi-breast phantom were 32.6% ± 5.3% without bolus to 96.7% ± 9.1%, 107.3% ± 9.0%, and 110.2% ± 8.7%, respectively. A film measurement shows that the dose at depths of 3, 5, and 10 cm is nearly same with or without brass bolus and the percentage difference is <1.5% at these depths. Mean surface doses from 6 patients treated with brass bolus ranged from 79.5% to 84.9%. The bolus application was discontinued between 18th and 23rd fractions on the development of Grade 2 skin toxicity for different patients. The total skin dose to chest wall for a patient was 3699 cGy from overall treatment with and without bolus. CONCLUSIONS: Brass mesh bolus does not significantly change dose at depths, and the surface dose is increased. This may be used as a substitute for tissue-equivalent bolus to improve surface conformity in PMRT.

Assessment of fatigability, depression, and self-esteem among head-and-neck carcinoma patients in a tertiary care hospital in South India.

BACKGROUND: Head and Neck Carcinoma (HNCs) are the most common form of cancer in India. Patients with head-and-neck carcinomas often suffer from various distressing symptoms. The exact cause of these symptoms, as to whether disease or treatment or other factor induced, needs to be established. OBJECTIVES: This study was done to assess fatigability, depression, and self-esteem among HNC study group before start, during, and in postradiation period and to find out the determinants of these parameters. MATERIALS AND METHODS: Seventy newly diagnosed HNC patients and equivalent number of age- and gender-matched controls were interviewed using standardized questionnaires, before start of concurrent chemoradiotherapy (CCRT). The study group patients were interviewed again in the 4th week and postcompletion of CCRT in the 7th week. RESULTS: Mean age of the study group was 55.1 ± 11.3 years. Three-fourth of them (52 [74.3%]) were males. Majority of them (26 [37.1%]) had oral carcinomas. Baseline fatigue (P < 0.001) and depression scores (P < 0.001) were significantly more, while self-esteem scores (P = 0.004) were significantly less among the study group compared to controls before the onset of radiation. Mean fatigue and depression scores were found to significantly increase (P < 0.001), while self-esteem scores were found to significantly deteriorate (P < 0.001) over the course of CCRT among these patients. There was significant positive correlation (P < 0.001) between fatigue and depression scores and negative correlation (P < 0.001) of these parameters with self-esteem scores before, during, and after CCRT. There was no association between age and gender of the study group with any of these parameters. Multivariate analysis showed that baseline fatigue was significant (P < 0.001) and, depression after completion of the entire course of CCRT was significantly influenced by baseline depression levels (P = 0.011). CONCLUSIONS: Fatigue and depression need to be periodically screened among HNC study group on CCRT so as to initiate prompt remedial measures for its alleviation.

Effectiveness of exercise-based rehabilitation on functional capacity and quality of life in head and neck cancer patients receiving chemo-radiotherapy.

PURPOSE: Fatigue, decreased functionality, and impaired quality of life are some of the most common adverse outcomes of chemo-radiotherapy (CRT). Head and neck cancers (HNC) affect more than half a million individuals globally and its treatment takes a heavy toll on the patient, often affecting their speech, swallowing, and respiratory functions, and as a result they often develop fatigue, depression, and physical inactivity. The purpose of this study was to evaluate the effectiveness of exercise-based rehabilitation on functional capacity, quality of life, fatigue, hemoglobin, and platelet counts in patients with HNC on CRT. PATIENTS AND METHODS: A randomized controlled trial was conducted on 148 patients with head and neck cancer undergoing CRT to evaluate the effectiveness of exercise on functional capacity measured by the 6-min walk test, quality of life measured by the Medical Outcomes Survey Short Form 36 v2 questionnaire, fatigue by the NCCN (0-10) scale, hemoglobin, and platelets. The control group received standard physical activity recommendations while the exercise group received a structured exercise program of aerobic and active resistance exercises for a period of 11 weeks. RESULTS: There was a significant improvement in the functional capacity (p < 0.001), quality of life (p < 0.001), and prevention of worsening of fatigue (p < 0.001) in the exercise group. The blood parameters did not show a significant difference between the control group and the exercise group. CONCLUSION: Our results elucidate that an 11-week structured exercise program for HNC patients receiving CRT helps in improving their functional capacity and quality of life. It also prevents deterioration of fatigue levels in the exercise group.

Anticarcinogenic activity of blue fluorescent hexagonal boron nitride quantum dots: as an effective enhancer for DNA cleavage activity of anticancer drug doxorubicin.

Blue fluorescent hexagonal boron nitride quantum dots (h-BNQDs) of ∼10 nm size as an effective enhancer for DNA cleavage activity of anticancer drug doxorubicin (DOX) were synthesized using simple one-step hydrothermal disintegration of exfoliated hexagonal boron nitride at very low temperature âˆ¼ 120 °C. Boron nitride quantum dots (BNQDs) at a concentration of 25 µg/ml enhanced DNA cleavage activity of DOX up to 70% as checked by converting supercoiled fragment into nicked circular PBR322 DNA. The interaction of BNQDs with DOX is proportional to the concentration of BNQDs, with binding constant K b ∼0.07338 µg/ml. In addition, ab initio theoretical results indicate that DOX is absorbed on BNQDs at the N-terminated edge with binding energy -1.075 eV and prevented the normal replication mechanisms in DNA. BNQDs have been shown to kill the breast cancer cell MCF-7 extensively as compared with the normal human keratinocyte cell HaCaT. The cytotoxicity of BNQDs may be correlated with reduced reactive oxygen species level and increased apoptosis in MCF-7 cells, which may be liable to enhance the anticancerous activity of DOX. The results provide a base to develop BNQD-DOX as a more effective anticancer drug.

Assessment of spectrum of mental disorders in cancer patients.

CONTEXT: Cancer is one of the leading causes of disability worldwide. The psychological factors that significantly affect the functioning of the cancer patients are anxiety, depressive disorders, and somatization. AIMS: To find out the spectrum of psychological disorders in cancer patients, also to find the association between sociodemographic variables and stage of tumor, treatment modality with the various psychological problems among cancer patients. SETTINGS AND DESIGN: This cross-sectional study was carried out among cancer patients undergoing treatment in our institution. SUBJECTS AND METHODS: Patient Health Questionnaire (PHQ)-somatization, anxiety, depression screeners is a prevalidated standard questionnaire which is a combination of PHQ-9, generalized anxiety disorder 7, and PHQ-15 plus panic measures from original PHQ. This questionnaire was given to patients and assessed later. STATISTICAL ANALYSIS: The association between variables of interest is tested using Chi-square test. P < 0.05 is be considered statistically significant. The data were analyzed using SPSS version 16 (SPSS for Windows, Version 16.0. Chicago, SPSS Inc.). RESULTS: Patients suffered from depression and also from other psychiatric morbidities. There was significant association among residential addresses and various scale (P < 0.05), PHQ-9 was maximum among radiotherapy patients (P = 0.04). PHQ-15 had association with stage of cancer (P = 0.007). CONCLUSION: Psychological problems are highest among patients from rural areas and among female patients compared to male. Highest anxiety and somatization was found among patients in Stage II cancer and depression in Stage IV cancer. Among treatment modalities, highest anxiety was found among patients under chemotherapy treatment, somatization among patients under both chemotherapy and radiotherapy, and depression among patients under radiotherapy treatment.

In vivo dose estimations through transit signal measured with thimble chamber positioned along the central axis at electronic portal imaging device level in medical linear accelerator in carcinoma of the middle-third esophagus patients undergoing three-dimensional conformal radiotherapy.

OBJECTIVE: This study presents a method to estimate midplane dose (Diso, transit) in vivo from transit signal (St) measured with thimble ionization chamber in cancer of the middle-third esophagus patients treated with three-dimensional radiotherapy (RT). This detector is positioned at the level of electronic portal imaging device in the gantry of a medical linear accelerator. MATERIALS AND METHODS: Efficacy of inhomogeneity corrections of three dose calculation algorithms available in XiO treatment planning system (TPS) for planned dose (for open fields) (Diso, TPS) was studied with three heterogeneous phantoms. Diso, transit represents measured signal at transit point (St) far away correlating to dose at isocenter. A locally fabricated thorax phantom was used to measure the in vivo midplane dose (Diso, mid) which was also estimated through St. Thirteen patients with carcinoma of the middle-third esophagus treated with three-dimensional conformal RT were studied. St was recorded (three times, with a gap of 5-6 fractions during the treatment) to estimate Diso, transit, which was compared with the doses calculated by TPS. RESULTS: The dose predictions by superposition algorithm were superior compared to the other algorithms. Percentage deviation of Diso, transit, Diso, mid with Diso, TPS combined all fields was 2.7 and -2.6%, respectively, with the thorax phantom. The mean percentage deviation with standard deviation of estimated Diso, transit with Diso, TPS observed in patients was within standard deviation -0.73% ±2.09% (n = 39). CONCLUSIONS: Midplane dose estimates in vivo using this method provide accurate determination of delivered dose in the middle-third esophagus RT treatments. This method could be useful in similar clinical circumstances for dose confirmation and documentation.