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The development of wearable devices provides approaches for the realization of self-health care. Easily carried wearable devices allow individual health monitoring at any place whenever necessary. There are various interesting monitoring targets, including body motion, organ pressure, and biomarkers. An efficient use of space in one small device is a promising resolution to increase the functions of wearable devices. Through integration of a microfluidic system into wearable devices, embedding complicated structures in one design becomes possible and can enable multifunction analyses within a limited device volume. This article reviews the reported microfluidic wearable devices, introduces applications to different biofluids, discusses characteristics of the design strategies and sensing principles, and highlights the attractive configurations of each device. This review seeks to provide a detailed summary of recent advanced microfluidic wearable devices. The overview of advanced key components is the basis for the development of future microfluidic wearable devices. Expected final online publication date for the Annual Review of Analytical Chemistry, Volume 16 is June 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Image-guided radiotherapy (IGRT) is an advanced auxiliary radiotherapy technique. During cancer treatment, patients with oral cavity cancer (OCC) experience not only disease but also adverse effects due to RT. IGRT provides the relevant advantages of RT by precisely delivering tumoricidal doses via real-time knowledge of the target volume location and achieves maximal tumor control with minimal complications as recommended for cancer treatment. Additionally, studies have shown that IGRT can improve clinical outcomes in terms of not only treatment side effects but also survival benefits for cancer patients. IGRT can be performed alongside various imaging methods, including computed tomography and magnetic resonance imaging, and at different times during the radiotherapy regimen. This article reviews the literature to discuss the effects and importance of IGRT for patients with OCC, examines the rationale underlying the advantages of IGRT, discusses the limitations of IGRT with respect to different techniques, and summarizes the strategies and future prospects of IGRT in the treatment of OCC.

Purpose The purpose of this study is to introduce half‐beam volumetric‐modulated arc therapy (HVMAT), an innovative treatment planning technique from our work, for reducing dose to the organs at risk (OAR) during adjuvant radiotherapy for gynecological cancers. Methods and materials Seventy‐two treatment plans of 36 patients with gynecological cancers receiving adjuvant radiotherapy were assessed. Among them, 36 plans were designed using HVMAT and paired with the other 36 traditional volumetric‐modulated arc therapy (VMAT) plans for each patient. The main uniqueness of the HVMAT designs was that it consisted of two opposite‐shielded half‐beam fields rotated inversely in two coplanar arcs, collocating with the specially‐devised avoidance structures to enhance the control of the OAR doses. The dose distributions in HVMAT and VMAT were evaluated and compared using the random effects model. Results The ratios of OAR doses in HVMAT compared with VMAT showed a comprehensive OAR dose reduction when using HVMAT (V 20Gy: bladder, 0.92; rectum, 0.95; V 30Gy: bowel, 0.91; femoral heads, 0.66), except for the ilium (V 30Gy: 1.12). The overall mean difference for each OAR across V 40Gy, V 30Gy, V 20Gy, and bowel V 15Gy was statistically significant (almost all p

Purpose To introduce the benefits of tangent-based volumetric modulated arc therapy (TVMAT), an innovative radiotherapy planning technique, compared with traditional volumetric modulated arc therapy (VMAT) for advanced left breast cancer needing nodal irradiation. Materials and methods Twenty-three patients with advanced left breast cancer who had received modified radical mastectomy (MRM) and needed adjuvant radiotherapy including nodal irradiation were assessed. Among 23 radiotherapy treatment plans, 17 plans were designed by using TVMAT technique and 6 plans were designed by using traditional VMAT. The main difference of TVMAT from VMAT was that the area of avoidance sector within specific degrees of angle that had no monitor unit (MU) delivery was used in the arc planning, including a total of 5 sectors in 5 partial arcs. The dosimetries of planning target volume (PTV), right breast, bilateral lungs, and heart between TVMAT and VMAT were compared. Results The conformity index (CI) and homogeneity index (HI) of PTV between two groups were statistically equivalent (CI: 0.98 ± 0.02 and 0.98 ± 0.03, P = 0.431; HI: 0.12 ± 0.03 and 0.11 ± 0.05, P = 0.177), which indicated that the treatment efficacy of the plans regarding TVMAT was compatible with VMAT. However, all neighboring organs at risk (OAR) showed a great percentage of reduction in mean doses (right breast: 53.1%, right lung: 37.7%, left lung: 8.8%, heart: 21.2%) and low dose parameters (V10: right breast: 72.3%, right lung: 86.1%, left lung: 12.5%, heart: 25.1%; V5: right breast: 56.5%, right lung: 28.3%, left lung: 12.7%, heart: 18.2%) by using TVMAT. Conclusion TVMAT greatly decreases the radiation doses delivered to the OAR with maintained therapeutic efficacy. It is highly recommended for treating breast cancer, especially for difficult cases with left side disease needing nodal irradiation.

The purpose of this study is to investigate the dose perturbation caused by the metal ovoid structures of a Henschke applicator using Monte Carlo simulation in a realistic phantom. The Henschke applicator has been widely used for gynecologic patients treated by brachytherapy in Taiwan. However, the commercial brachytherapy planning system (BPS) did not properly evaluate the dose perturbation caused by its metal ovoid structures. In this study, Monte Carlo N-Particle Transport Code eXtended (MCNPX) was used to evaluate the brachytherapy dose distribution of a Henschke applicator embedded in a Plastic water phantom and a heterogeneous patient computed tomography (CT) phantom. The dose comparison between the MC simulations and film measurements for a Plastic water phantom with Henschke applicator were in good agreement. However, MC dose with the Henschke applicator showed significant deviation (−80.6%±7.5%) from those without Henschke applicator. Furthermore, the dose discrepancy in the heterogeneous patient CT phantom and Plastic water phantom CT geometries with Henschke applicator showed 0 to −26.7% dose discrepancy (−8.9%±13.8%). This study demonstrates that the metal ovoid structures of Henschke applicator cannot be disregard in brachytherapy dose calculation.

Background Tangent-based intensity modulated radiation therapy (TIMRT) is a common adjuvant radiotherapy strategy for breast cancer patients. This study compared the dosimetric characteristics of tangent-based volumetric modulated arc therapy (TVMAT) and TIMRT for left breast cancer patients during deep inspiration breath-hold (DIBH) and free breathing (FB) techniques. Methods Fourteen patients with left breast cancer after breast-conserving surgery were included. The first arc started at 331.8–353.6 degrees and stopped at 281.8–315.0 degrees. The third arc started at 123.2–149.1 degrees and stopped at 88.0–96.0 degrees. The second and fourth arcs were reverse arcs of first and third arcs. DIBH-TIMRT inversing plans were generated using opposing tangential fields. Wilcoxon signed rank test and Spearman correlation were used to examine the significance of dose difference. Results Compared with FB-TVMAT, the mean heart dose of DIBH-TVMAT plans was reduced from 7.9 Gy to 3.2 Gy (p

Cervical cancer patients may sometimes experience different types of uterine perforation by a tandem during brachytherapy. The purpose of this study was to address possibly different management strategies regarding different tandem positions from a dosimetry aspect by evaluating radiation doses delivered to organs-at-risk (OAR) in order to help medical professionals handle different types of uterine perforation. Images and dosimetry data in cervical cancer brachytherapy with uterine perforation were reviewed. Uterine perforation was classified into anterior and posterior perforation according to their tandem positions. Radiation doses received by OAR, including D2cc and D1cc of the bladder, rectum, and sigmoid colon, were statistically compared with nonperforation. The doses of high-risk clinical target volume (HR-CTV) of cervical tumor and bilateral point A were also compared in order to assure that the plans had not compromised the treatment efficacy. A total of 21 applications were assessed, including 5 with anterior perforation, 4 with posterior perforation, and 12 without perforation. In anterior perforation, the bladder was the only organ that received a significantly increased dose about 30% at D2cc and D1cc. However, in posterior perforation, multiple OAR received significantly excessive doses: approximately 30% for the bladder, 37% for the rectum, and 100% for the sigmoid colon. The OAR dose assessment was based on a statistically equivalent cervical tumor dose. Different management strategies are possible for anterior vs posterior perforation during brachytherapy due to different detrimental extents on OAR dosimetry. The bladder warrants more attention in anterior perforation, without compromising target coverage in treatment planning. On the other hand, repositioning may be considered in posterior perforation due to relatively massive OAR detriments. This concept is a new one and is given for the first time.

Background To analyze the respiratory-induced motion of each liver segment using helical computed tomography (helical CT) and 4-dimensional computed tomography (4DCT), and to establish the individual segment expansion margin of internal target volume (ITV) to facilitate target delineation of tumors in different liver segments. Methods Twenty patients who received radiotherapy with CT-simulation scanning of the whole liver in both helical CT and 10-phase-gated 4DCT were investigated, including 2 patients with esophagus cancer, 4 with lung cancer, 10 with breast cancer, 2 with liver cancer, 1 with thymoma, and 1 with gastric diffuse large B-cell lymphoma (DLBCL). For each patient, 9 representative points were drawn on the helical CT images of liver segments 1, 2, 3, 4a, 4b, 5, 6, 7, and 8, respectively, and adaptively deformed to 2 phases of the 4DCT images at the end of inspiration (phase 0 CT) and expiration (phase 50 CT) in the treatment planning system. Using the amplitude of each point between phase 0 CT and phase 50 CT, we established quantitative data for the respiration-induced motion of each liver segment in 3-dimensional directions. Moreover, using the amplitude between the original helical CT and both 4DCT images, we rendered the individual segment expansion margin of ITV for hepatic target delineation to cover more than 95% of each tumor. Results The average amplitude (mean ± standard deviation) was 0.6 ± 3.0 mm in the left-right (LR) direction, 2.3 ± 2.4 mm in the anterior-posterior (AP) direction, and 5.7 ± 3.4 mm in the superior-inferior (SI) direction, respectively. All of the segments moved posteriorly and superiorly during expiration. Segment 7 had the largest amplitude in the SI direction, at 8.6 ± 3.4 mm. Otherwise, the segments over the lateral side, including segments 2, 3, 6, and 7, had greater excursion in the SI direction compared to the medial segments. To cover more than 95% of each tumor, the required expansion margin of ITV in the LR, AP, and SI directions were at least 2.5 mm, 2.5 mm, and 5.0 mm on average, respectively, with variations between different segments. Conclusions The greatest excursion occurred in liver segment 7, followed by the segments over the lateral side in the SI direction. The individual segment expansion margin of ITV is required to delineate targets for each segment and direction.

Background This was a retrospective study of patients with human papillomavirus (HPV)-associated oropharyngeal cancer treated with concurrent systemic therapy and radiation. Methods Data were extracted through chart review, and statistical analyses included frequency tabulation, chi-square, and Kaplan–Meier tests. Results Three hundred thirty-nine patients were analyzed; 166 received neoadjuvant chemotherapy. One hundred thirty-six patients were treated with cisplatin, 123 with cetuximab, and 59 with carboplatin. The 2-, 3-, and 5-year actuarial overall survival rates were 92%, 88%, and 78%, respectively. There were no significant differences in survival or disease control when analyzed by systemic agent. Platin-treated patients had greater hematologic toxicity, and required more intravenous hydration. The incidence of confluent mucositis was highest among patients treated with cetuximab. Conclusion Platin and cetuximab seem to have similar efficacy when delivered concurrently with radiation in our retrospective population study. Although platin did cause greater hematologic toxicity, radiation-specific side effects seemed relatively comparable. © 2015 Wiley Periodicals, Inc. Head Neck, 2015

Background/Purpose Evidence on the prevention of radiation dermatitis is lacking. The aim of this study was to investigate the effect of 3M Cavilon No Sting Barrier Film and topical corticosteroids on irradiated skin. Methods Thirty-nine postoperative breast cancer patients were randomized into three groups for intraindividual comparison (skin to be irradiated was divided into 2 parts): (1) 3M No Sting Barrier Film versus no treatment; (2) corticosteroid versus no treatment; and (3) corticosteroid versus 3M No Sting Barrier Film. The primary end points monitored were the time to first occurrence of grade 1 pruritus, pain score of 3 and grade 2 radiation dermatitis. The secondary end points studied were the incidence of grade 3 radiation dermatitis and total pain scores. Data analysis was done using the SPSS software version 10. Results Skin given the 3M barrier film experienced a later occurrence of pruritus compared to both corticosteroids and untreated, although this was statistically insignificant. Corticosteroids delayed the time to occurrence of grade 2 dermatitis compared to both untreated skin and 3M barrier film, (mean day of onset = corticosteroid: 52 vs. untreated: 43, p = 0.092; corticosteroid: 53.4 vs. 3M barrier film: 44.5, p = 0.002, t test). Skin given corticosteroids had the lowest incidence of grade 3 dermatitis among all three conditions, although the differences were statistically insignificant. No statistically significant differences were noted in total pain scores. Conclusion The 3M barrier film may be helpful against dermatitis associated pruritus. Corticosteroids may delay the time of onset of severe skin reactions and also reduce the incidence of severe radiation dermatitis.

Purpose Increasing number of breast cancer women receiving post-mastectomy radiation therapy (PMRT) had immediate two-stage tissue expander (TE)/implant for breast reconstruction. TEs with metallic port become popular due to convenient saline injection. Previous studies showed 10–30% actual dose reduction under tangential beam arrangement caused by high Z material. This study was conducted to quantify the dosimetric effects in the region of the metallic ports using helical tomotherapy. Methods Bolus with 0.5 cm thickness was placed on the surface of rando-phantom simulating post mastectomy pectoralis major and skin beyond as layer M. TE with different capacities (100 cc, 150 cc, 200 cc, 250 cc, and 300 cc) was placed under layer M simulating treatment condition. 1 cm bolus was placed on layer M for routine PMRT technique. Artifact removement and heterogeneity correction of simulation image were performed via tomotherapy planning system. Two tomotherapy plans were generated for each capacity of TE: Plan A) artifact removed; Plan B) artifact removed plus CT electron density 1 was assigned to the metallic port region. Radiochromic films were used for absolute dose measurement at three locations: 1) surface of layer M; interface between 2) TE and layer M 3) bottom of TE. Film QA was utilized for dose analysis. Results The distance between TE top and metallic port is range from 0.7 for small capacity to 1.0 cm for large capacity. The distance between metallic port and TE bottom is range from 0 to 1.4 cm along with increasing capacity. The measured dose at layer M surface was range from −0.53% to −8.9% and −0.39% to −8.29% for plan A and B. The measured dose at interface between TE and layer M was range from 1.09% to −6.01% and 1.92% to −6.09% for plan A and B. The measured dose at bottom of TE was range from −0.14% to −7.57% and 1.08% to −5.37% for plan A and B. Conclusions The actual dose under helical tomotherapy for patient with metallic port breast tissue expander is acceptable comparing to tangential technique. TEs with 100 cc and 150 cc have higher metallic port position reproducibility. Helical tomotherapy is a suitable treatment technique for patient with breast tissue expander with metallic port.

Purpose This study was to quantify the correlation of the infrared reflecting marker movement and deep inspiration breath-hold (DIBH) lung expansions by setting the infrared reflecting marker below the xiphoid process on the abdominal wall. Methods Ten patients with left breast cancer post operation underwent free-breathing (FB) and DIBH computed tomography (CT) using infrared reflecting marker on the abdominal wall. Therapists coached patient breathing maneuvers before CT scans. The breath-hold level (BHL) was recorded by infrared reflecting marker in the anteroposterior (AP) direction by Real-time Position Management system (RPM) system during CT procedure. Lung diameter in AP direction on both free-breathing (FB) and DIBH images were measured at 4 levels: half upper, upper border of heart, half lower and diaphragm levels of lung. The first CT slice with visible lung tissue and diaphragm level were identified for lung diameter in superioinferior (SI) direction corresponding Z values (slice position). Pearson correlation test was used to examine the correlation significance among BHL, lung AP diameter, lung SI diameter, heart dose, and left lung dose. Results The BHL had strongly positive correlation with lung expansion in SI direction (Pearson correlation r = 0.770). When BHL increased 1.0 cm, the lung expansion in SI direction increased 2.6 cm. Also, moderately positive correlation was revealed between BHL and total lung volume (Pearson correlation r = 0.596). When BHL increased 1.0 cm, the total lung volume increased 414.1c.c. Heart mean dose and maximum dose were strongly negative correlated to BHL according to inverse square law. Weak or no correlation was noted between BHL and lung expansion in AP direction at 4 levels (Pearson correlation r = 0.318, 0.009, −0.105 and −0.238). DIBH plans had lower heart dose (2.64 vs. 1.32 Gy; P = 0.005) and ipsilateral lung V20 (%) relative volume (13.6 vs. 10.9 %; P = 0.007) than FB plans as previous studies. Conclusions Setting infrared reflecting marker below the xiphoid process on the abdominal wall is sufficient for DIBH technique to detect lung expansion in SI direction and decrease the heart dose significantly. Patient couching before CT scans is recommended.

Background: Adjuvant radiotherapy reduces local recurrence and improves overall survival of breast cancer. But adjuvant radiotherapy also leads to excess mortality caused by heart and lung disease. Deep inspiration breath hold (DIBH) technique has been proven to reduce radiation exposure to heart and lung. However, effectiveness of DIBH variates from each patient. This study collected one institutional data and further analyzed associated physical factors. Methods: Left breast cancer patients received left partial mastectomy followed by adjuvant radiotherapy with DIBH technique between Sep 1, 2013 and Sep 1, 2014 were included. Treatment plans based on both free breathing (FB) and DIBH computed tomography scan image for each patient were constructed. Physical factors including chest wall expansion at different levels were measured. Dose of ipsilateral, contralateral, and total lung, and heart were compared between FB and DIBH. Correlation between normal organ irradiated dose and physical factors change were calculated by Pearson correlation test. Results: Anterior-to-posterior diameter (APd) increase of lung at half upper chest wall level, upper heart border level, and half lower chest wall level, and extra lung length of DIBH had positive correlation with the reduction of irradiated lung dose. The increase of APd of lung at upper heart border level, half lower chest wall level, and right-to-left diameter (RLd) at diaphragm level also had positive correlation with the reduction of Dmax of heart (Pearson correlation r=0.795, 0.835, 0.655; P=0.006, 0.003, and 0.04, respectively) and Dmax of left anterior descending artery (LAD) (r=0.788, 0.795, 0.673; P=0.007, 0.006, and 0.033, respectively). Increase of free-contour heart height had negative correlation with V30, Dmax of heart, and Dmax of LAD. Conclusions: DIBH can reduce dose to critical organs. One-point chest wall motion monitored by Realtime Position Management TM (RPM) system can only represent the change of APd at diaphragm level and part of the change of half of lower chest wall level. Respiration is a complicated motion and multiple level monitoring system was suggested. Patient education to explain the idealist chest wall expansion condition with DIBH is important. Our CT-based instruction model provides a clearer instruction. This study suggested a new direction to evaluate and enhance DIBH performance.

This was a retrospective study of patients with human papillomavirus (HPV)-associated oropharyngeal cancer treated with concurrent systemic therapy and radiation.Data were extracted through chart review, and statistical analyses included frequency tabulation, chi-square, and Kaplan-Meier tests.Three hundred thirty-nine patients were analyzed; 166 received neoadjuvant chemotherapy. One hundred thirty-six patients were treated with cisplatin, 123 with cetuximab, and 59 with carboplatin. The 2-, 3-, and 5-year actuarial overall survival rates were 92%, 88%, and 78%, respectively. There were no significant differences in survival or disease control when analyzed by systemic agent. Platin-treated patients had greater hematologic toxicity, and required more intravenous hydration. The incidence of confluent mucositis was highest among patients treated with cetuximab.Platin and cetuximab seem to have similar efficacy when delivered concurrently with radiation in our retrospective population study. Although platin did cause greater hematologic toxicity, radiation-specific side effects seemed relatively comparable. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1554-E1561, 2016.

Background: Planning skills such as skin flash in intensity-modulated radiation therapy (IMRT), virtual bolus in helical tomotherapy (HT) and tissue equivalent materials are widely used in breast cancer radiotherapy (RT) to ensure coverage of superficial target under respiration. This study was conducted to evaluate the exact skin dose under above treatment technique and planning skills. Methods: Women who received whole breast RT (WBRT) or post-mastectomy RT (PMRT) were included. Treatment machines included Synergy ® (Elekta, Stockholm, Sweden) and TomoTherapy Hi-ART ® (Accuray, Sunnyvale, CA, USA). For WBRT, 20 mm “skin flash” was used in IMRT, and 10 mm “virtual bolus” was used in HT. For PMRT, 5 mm bolus plus skin flash was used in IMRT and 10 mm bolus was used in HT. GafChromic EBT3 (International Specialty Products, Wayne, NJ, USA) films were placed on patient’s skin for measurement. Results: Between July 2012 and December 2013, 17 patients in WBRT group and 13 patients in PMRT group were included. In WBRT group, patients received higher skin dose with IMRT than with HT (86.57% and 79.69% of prescribed dose, respectively, P Conclusions: For WBRT, HT plus virtual bolus leads to homogeneous skin dose distribution and 7% lower skin dose than IMRT does. For PMRT, HT plus 10 mm bolus provides adequate surface dose which is close to 100% of prescribed dose; while IMRT plus 5 mm bolus and skin flash results in overdose with 7% more than prescribed dose. HT should be considered to be an option of breast RT.