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203. Brachytherapy: An overview for clinicians

Author

Chargari, Cyrus, primary, Deutsch, Eric, additional, Blanchard, Pierre, additional, Gouy, Sebastien, additional, Martelli, Hélène, additional, Guérin, Florent, additional, Dumas, Isabelle, additional, Bossi, Alberto, additional, Morice, Philippe, additional, Viswanathan, Akila N., additional, and Haie‐Meder, Christine, additional

Published
2019
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205. Management of Nodal Disease in Advanced Cervical Cancer

Author

Jürgenliemk-Schulz, Ina-Maria, primary, Beriwal, Sushil, additional, de Leeuw, Astrid A.C., additional, Lindegaard, Jacob Christian, additional, Nomden, Christel Nadine, additional, Pötter, Richard, additional, Tanderup, Kari, additional, Viswanathan, Akila N., additional, and Erickson, Beth, additional

Published
2019
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207. Association of a Simulated Institutional Gender Equity Initiative With Gender-Based Disparities in Medical School Faculty Salaries and Promotions

Author

Rao, Avani D., primary, Nicholas, Sarah E., additional, Kachniarz, Bartlomiej, additional, Hu, Chen, additional, Redmond, Kristin J., additional, Deville, Curtiland, additional, Wright, Jean L., additional, Page, Brandi R., additional, Terezakis, Stephanie, additional, Viswanathan, Akila N., additional, DeWeese, Theodore L., additional, Fivush, Barbara A., additional, and Alcorn, Sara R., additional

Published
2018
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208. A novel minimally invasive dynamic‐shield, intensity‐modulated brachytherapy system for the treatment of cervical cancer.

Author

Morcos, Marc, Antaki, Majd, Viswanathan, Akila N., and Enger, Shirin A.

Subjects
MONTE Carlo method, RADIOISOTOPE brachytherapy, CERVICAL cancer, CANCER treatment, INTERSTITIAL brachytherapy, RADIOISOTOPES, RECTUM
Abstract

Purpose: To present a novel, MRI‐compatible dynamicshield intensity modulated brachytherapy (IMBT) applicator and delivery system using 192Ir, 75Se, and 169Yb radioisotopes for the treatment of locally advanced cervical cancer. Needle‐free IMBT is a promising technique for improving target coverage and organs at risk (OAR) sparing. Methods and materials: The IMBT delivery system dynamically controls the rotation of a novel tungsten shield placed inside an MRI‐compatible, 6‐mm wide intrauterine tandem. Using 36 cervical cancer cases, conventional intracavitary brachytherapy (IC‐BT) and intracavitary/interstitial brachytherapy (IC/IS‐BT) (10Ci 192Ir) plans were compared to IMBT (10Ci 192Ir; 11.5Ci 75Se; 44Ci 169Yb). All plans were generated using the Geant4‐based Monte Carlo dose calculation engine, RapidBrachyMC. Treatment plans were optimized then normalized to the same high‐risk clinical target volume (HR‐CTV) D90 and the D2cc for bladder, rectum, and sigmoid in the research brachytherapy planning system, RapidBrachyMCTPS. Plans were renormalized until either of the three OAR reached dose limits to calculate the maximum achievable HR‐CTV D90 and D98. Results: Compared to IC‐BT, IMBT with either of the three radionuclides significantly improves the HR‐CTV D90 and D98 by up to 5.2% ± 0.3% (P < 0.001) and 6.7% ± 0.5% (P < 0.001), respectively, with the largest dosimetric enhancement when using 169Yb followed by 75Se and then 192Ir. Similarly, D2cc for all OAR improved with IMBT by up to 7.7% ± 0.6% (P < 0.001). For IC/IS‐BT cases, needle‐free IMBT achieved clinically acceptable plans with 169Yb‐based IMBT further improving HR‐CTV D98 by 1.5% ± 0.2% (P = 0.034) and decreasing sigmoid D2cc by 1.9% ± 0.4% (P = 0.048). Delivery times for IMBT are increased by a factor of 1.7, 3.3, and 2.3 for 192Ir, 75Se, and 169Yb, respectively, relative to conventional 192Ir BT. Conclusions: Dynamic shield IMBT provides a promising alternative to conventional IC‐ and IC/IS‐BT techniques with significant dosimetric enhancements and even greater improvements with intermediate energy radionuclides. The ability to deliver a highly conformal, OAR‐sparing dose without IS needles provides a simplified method for improving the therapeutic ratio less invasively and in a less resource intensive manner. [ABSTRACT FROM AUTHOR]

Published
2021
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216. CHARACTERIZING GRADIENT ECHO SIGNAL DECAYS IN GYNECOLOGIC CANCERS AT 3T USING A GAUSSIAN AUGMENTATION OF THE MONO-EXPONENTIAL (GAME) MODEL

Author

Ciris, Pelin A., Balasubramanian, Mukund, Damato, Antonio L., Seethamraju, Ravi T., Tempany-Afdhal, Clare M., Mulkern, Robert V., and Viswanathan, Akila N.

Subjects
Adult, Models, Statistical, Genital Neoplasms, Female, Normal Distribution, Reproducibility of Results, Middle Aged, Image Enhancement, Magnetic Resonance Imaging, Sensitivity and Specificity, Article, Oxygen, Image Interpretation, Computer-Assisted, Biomarkers, Tumor, Humans, Tumor Hypoxia, Computer Simulation, Female, Aged
Abstract

To assess whether R2* mapping with a standard Monoexponential (ME) or a Gaussian Augmentation of the Monoexponential (GAME) decay model better characterizes gradient-echo signal decays in gynecological cancers after external beam radiation therapy at 3T, and evaluate implications of modeling for noninvasive identification of intratumoral hypoxia.Multi-gradient-echo signals were acquired on 25 consecutive patients with gynecologic cancers and three healthy participants during inhalation of different oxygen concentrations at 3T. Data were fitted with both ME and GAME models. Models were compared using F-tests in tumors and muscles in patients, muscles, cervix, and uterus in healthy participants, and across oxygenation levels.GAME significantly improved fitting over ME (P0.05): Improvements with GAME covered 34% of tumor regions-of-interest on average, ranging from 6% (of a vaginal tumor) to 68% (of a cervical tumor) in individual tumors. Improvements with GAME were more prominent in areas that would be assumed hypoxic based on ME alone, reaching 90% as ME R2* approached 100 Hz. Gradient echo decay parameters at different oxygenation levels were not significantly different (P = 0.81).R2* may prove sensitive to hypoxia; however, inaccurate representations of underlying data may limit the success of quantitative assessments. Although the degree to which R2 or σ values correlate with hypoxia remains unknown, improved characterization with GAME increases the potential for determining any correlates of fit parameters with biomarkers, such as oxygenation status. J. MAGN. RESON. IMAGING 2016;44:1020-1030.

Published
2016

217. Medical Student Perspectives on a Multi-institutional Clerkship Curriculum: A Report From the Radiation Oncology Education Collaborative Study Group

Author

Ye, Jason C., Mohindra, Pranshu, Spektor, Alexander, Krishnan, Monica S., Chmura, Steven J., Howard, Andrew R., Viswanathan, Akila N., MacDonald, Shannon M., Thaker, Nikhil G., Das, Prajnan, Mancini, Brandon R., Higgins, Susan A., Braunstein, Steve, Haas-Kogan, Daphne, Bradley, Kristin A., Hung, Arthur Y., Thomas, Charles R., Jr., Kharofa, Jordan, Wheatley, Matt, Currey, Adam, Parashar, Bhupesh, Du, Kevin, Jimenez, Rachel B., and Golden, Daniel W.

Published
2015
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218. Pelvic Radiation and Normal Tissue Toxicity

Author

Nicholas, Sarah, primary, Chen, Linda, additional, Choflet, Amanda, additional, Fader, Amanda, additional, Guss, Zachary, additional, Hazell, Sarah, additional, Song, Daniel Y., additional, Tran, Phuoc T., additional, and Viswanathan, Akila N., additional

Published
2017
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219. Corrigendum to “comparison of outcomes for MR-guided versus CT-guided high-dose-rate interstitial brachytherapy in women with locally advanced carcinoma of the cervix” [Gynecol. Oncol. 145 (2017) 284–290]

Author

Kamran, Sophia C., primary, Manuel, Matthias M., additional, Cho, Linda P., additional, Damato, Antonio L., additional, Schmidt, Ehud J., additional, Tempany, Clare, additional, Cormack, Robert A., additional, and Viswanathan, Akila N., additional

Published
2017
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220. Cervical cancer: A global health crisis

Author

Small, William, primary, Bacon, Monica A., additional, Bajaj, Amishi, additional, Chuang, Linus T., additional, Fisher, Brandon J., additional, Harkenrider, Matthew M., additional, Jhingran, Anuja, additional, Kitchener, Henry C., additional, Mileshkin, Linda R., additional, Viswanathan, Akila N., additional, and Gaffney, David K., additional

Published
2017
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221. Radiation Oncology in India: Challenges and Opportunities

Author

Grover, Surbhi, primary, Gudi, Shivakumar, additional, Gandhi, Ajeet Kumar, additional, Puri, Priya M., additional, Olson, Adam C., additional, Rodin, Danielle, additional, Balogun, Onyi, additional, Dhillon, Preet K., additional, Sharma, Daya Nand, additional, Rath, Goura Kishor, additional, Shrivastava, Shyam Kishore, additional, Viswanathan, Akila N., additional, and Mahantshetty, Umesh, additional

Published
2017
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222. Characterization of efficacy and toxicity after high-dose pelvic reirradiation with palliative intent for genitourinary second malignant neoplasms or local recurrences after full-dose radiation therapy in the pelvis: A high-volume cancer center experience

Author

Kamran, Sophia C., primary, Harshman, Lauren C., additional, Bhagwat, Mandar S., additional, Muralidhar, Vinayak, additional, Nguyen, Paul L., additional, Martin, Neil E., additional, La Follette, Stephanie, additional, Faso, Sarah, additional, Viswanathan, Akila N., additional, Efstathiou, Jason A., additional, and Beard, Clair J., additional

Published
2017
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224. NRG ONCOLOGY/RTOG 0921: A PHASE II STUDY OF POSTOPERATIVE INTENSITY MODULATED RADIATION THERAPY (IMRT) WITH CONCURRENT CISPLATIN AND BEVACIZUMAB FOLLOWED BY CARBOPLATIN AND PACLITAXEL FOR PATIENTS WITH ENDOMETRIAL CANCER

Author

Viswanathan, Akila N., Moughan, Jennifer, Miller, Brigitte E., Xiao, Ying, Jhingran, Anuja, Portelance, Lorraine, Bosch, Walter, Matulonis, Ursula, Horowitz, Neil, Mannel, Robert S., Souhami, Luis, Erickson, Beth, Winter, Kathryn, Small, William, and Gaffney, David

Subjects
Adult, Aged, 80 and over, Paclitaxel, Chemoradiotherapy, Adjuvant, Middle Aged, Hysterectomy, Article, Disease-Free Survival, Endometrial Neoplasms, Bevacizumab, Antineoplastic Combined Chemotherapy Protocols, Humans, Lymph Node Excision, Female, Postoperative Period, Radiotherapy, Intensity-Modulated, Cisplatin, Aged
Abstract

The current study was conducted to assess acute and late adverse events (AEs), overall survival (OS), pelvic failure, regional failure, distant failure, and disease-free survival in a prospective phase 2 clinical trial of bevacizumab and pelvic intensity-modulated radiotherapy (IMRT) with chemotherapy in patients with high-risk endometrial cancer.Patients underwent a hysterectomy and lymph node removal, and had ≥1 of the following high-risk factors: grade 3 carcinoma with50% myometrial invasion, grade 2 or 3 disease with any cervical stromal invasion, or known extrauterine extension confined to the pelvis. Treatment included pelvic IMRT and concurrent cisplatin on days 1 and 29 of radiation and bevacizumab (at a dose of 5 mg/kg on days 1, 15, and 29 of radiation) followed by adjuvant carboplatin and paclitaxel for 4 cycles. The primary endpoint was grade ≥3 AEs occurring within the first 90 days (toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.0]).A total of 34 patients were accrued from November 2009 through December 2011, 30 of whom were eligible and received study treatment. Seven of 30 patients (23.3%; 1-sided 95% confidence interval, 10.6%-36.0%) developed grade ≥3 treatment-related nonhematologic toxicities within 90 days; an additional 6 patients experienced grade ≥3 toxicities between 90 and 365 days after treatment. The 2-year OS rate was 96.7% and the disease-free survival rate was 79.1%. No patient developed a within-field pelvic failure and no patients with International Federation of Gynecology and Obstetrics stage I to IIIA disease developed disease recurrence after a median follow-up of 26 months.Postoperative bevacizumab added to chemotherapy and pelvic IMRT appears to be well tolerated and results in high OS rates at 2 years for patients with high-risk endometrial carcinoma.

Published
2015

225. Cervix Cancer Research Network (CCRN): Improving Access to Cervix Cancer Trials on a Global Scale

Author

Gaffney, David, primary, Small, Bill, additional, Kitchener, Henry, additional, Young Ryu, Sang, additional, Viswanathan, Akila, additional, Trimble, Ted, additional, Covens, Al, additional, Wilailak, Sarikapan, additional, Lertkhachonsuk, Arb-aroon, additional, Sitathanee, Chomporn, additional, Mahantshetty, Umesh, additional, Fisher, Brandon, additional, Springer, Susan, additional, Pollatz, Thomas, additional, Spiller, Antonius, additional, Bacon, Monica, additional, and Jhingran, Anuja, additional

Published
2016
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226. HIV Infection and Survival Among Women With Cervical Cancer

Author

Dryden-Peterson, Scott, primary, Bvochora-Nsingo, Memory, additional, Suneja, Gita, additional, Efstathiou, Jason A., additional, Grover, Surbhi, additional, Chiyapo, Sebathu, additional, Ramogola-Masire, Doreen, additional, Kebabonye-Pusoentsi, Malebogo, additional, Clayman, Rebecca, additional, Mapes, Abigail C., additional, Tapela, Neo, additional, Asmelash, Aida, additional, Medhin, Heluf, additional, Viswanathan, Akila N., additional, Russell, Anthony H., additional, Lin, Lilie L., additional, Kayembe, Mukendi K.A., additional, Mmalane, Mompati, additional, Randall, Thomas C., additional, Chabner, Bruce, additional, and Lockman, Shahin, additional

Published
2016
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227. 76: IMRT for Vulvar Carcinoma: Changes in Practice Over 5 Years

Author

Barkati, Maroie, primary, King, Bronwyn, additional, Fortin, Israël, additional, Portelance, Lorraine, additional, Viswanathan, Akila, additional, Fyles, Anthony, additional, Beriwal, Sushil, additional, Alfieri, Joanne, additional, Lim, Karen, additional, Harkenrider, Matthew, additional, Small, William, additional, Klopp, Ann, additional, Stewart, Alexandra, additional, Yashar, Catheryn, additional, Bosch, Walter, additional, Jhingran, Anuja, additional, Jolicoeur, Marjorie, additional, and Gaffney, David, additional

Published
2016
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228. Treatment completion and tolerability of women with cervical cancer with and without HIV in Botswana.

Author

Grover, Surbhi, primary, Bvochora-Nsingo, Memory Fadziso, additional, MacDuffie, Emily, additional, Ratcliffe, Sarah, additional, Wileyto, E. Paul, additional, Bhatia, Rohini, additional, Yeager, Alyssa, additional, Chiyapo, Sebathu Phillip, additional, Gaolebale, Ponatshego A, additional, Russell, Anthony Henry, additional, Makufa, Remigio, additional, Karunmekayi, Talkmore, additional, Balang, Dawn, additional, Kayembe, Mukendi, additional, Ramogola-Masire, Doreen, additional, Dryden-Peterson, Scott, additional, Viswanathan, Akila N., additional, Robertson, Erle, additional, Zetola, Nicola Mario, additional, and Lin, Lilie L., additional

Published
2016
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230. Improved Dose Conformality in Non-Image Based Treatment Planning for Vaginal Cylinders Using Shallower Dose Optimization Points

Author

Harris, Thomas, primary, Bhagwat, Mandar, additional, Damato, Antonio, additional, O'Farrell, Desmond, additional, Friesen, Scott, additional, Hansen, Jorgen, additional, Lee, Larissa, additional, Viswanathan, Akila, additional, Devlin, Phillip, additional, Cormack, Robert, additional, and Buzurovic, Ivan, additional

Published
2016
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241. Multi-Institutional Implementation and Evaluation of a Curriculum for the Medical Student Clerkship in Radiation Oncology

Author

Golden, Daniel W., primary, Braunstein, Steve, additional, Jimenez, Rachel B., additional, Mohindra, Pranshu, additional, Spektor, Alexander, additional, Ye, Jason C., additional, Bradley, Kristin A., additional, Chmura, Steven J., additional, Currey, Adam, additional, Das, Prajnan, additional, Du, Kevin, additional, Haas-Kogan, Daphne, additional, Howard, Andrew R., additional, Higgins, Susan A., additional, Hung, Arthur Y., additional, Kharofa, Jordan, additional, Krishnan, Monica S., additional, MacDonald, Shannon M., additional, Mancini, Brandon R., additional, Parashar, Bhupesh, additional, Thaker, Nikhil G., additional, Thomas, Charles R., additional, Viswanathan, Akila N., additional, and Wheatley, Matt, additional

Published
2016
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247. Colaboradores

Author

Anscher, Mitchell S., Boggs, D. Hunter, Chan, Michael D., Cramer, Christina K., Cuaron, John, Santos, Jennifer De Los, Galloway, Thomas J., Garsa, Adam A., Gottschalk, Alexander R., Hess, Clayton B., Jeans, Elizabeth B., Kaidar-Person, Orit, Kalman, Noah S., Kamran, Sophia C., Kirkpatrick, John P., Krishnan, Monica, Marks, Lawrence B., Rossi, Peter J., Shiloh, Ron, Smith, Sophia K., Spector, Denise, Urdaneta, Alfredo I., Viswanathan, Akila N., Wu, Abraham, Yock, Torunn I., Yom, Sue S., Zagar, Timothy M., and Zhao, Sherry

Published
2018
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248. Validation of mathematical models for the prediction of organs-at-risk dosimetric metrics in high-dose-rate gynecologic interstitial brachytherapy

Author

Damato, Antonio L., Viswanathan, Akila N., and Cormack, Robert A.

Subjects
Radiation Therapy Physics, Organs at Risk, Genital Neoplasms, Female, Radiotherapy Planning, Computer-Assisted, Brachytherapy, Humans, Female, Radiotherapy Dosage, Models, Theoretical, Radiation Dosage, Radiometry
Abstract

PURPOSE: Given the complicated nature of an interstitial gynecologic brachytherapy treatment plan, the use of a quantitative tool to evaluate the quality of the achieved metrics compared to clinical practice would be advantageous. For this purpose, predictive mathematical models to predict the D(2cc) of rectum and bladder in interstitial gynecologic brachytherapy are discussed and validated. METHODS: Previous plans were used to establish the relationship between D2cc and the overlapping volume of the organ at risk with the targeted area (C0) or a 1-cm expansion of the target area (C1). Three mathematical models were evaluated: D(2cc) = α*C(1) + β (LIN); D(2cc) = α – exp(–β*C(0)) (EXP); and a mixed approach (MIX), where both C(0) and C(1) were inputs of the model. The parameters of the models were optimized on a training set of patient data, and the predictive error of each model (predicted D(2cc) − real D(2cc)) was calculated on a validation set of patient data. The data of 20 patients were used to perform a K-fold cross validation analysis, with K = 2, 4, 6, 8, 10, and 20. RESULTS: MIX was associated with the smallest mean prediction error

Published
2013

249. A fast inverse treatment planning strategy facilitating optimized catheter selection in image-guided high-dose-rate interstitial gynecologic brachytherapy.

Author

Guthier, Christian V., Damato, Antonio L., Hesser, Juergen W., Viswanathan, Akila N., and Cormack, Robert A.

Subjects
CATHETERS, ARTIFICIAL implants, CANCER treatment, DRUG delivery devices, RADIOISOTOPE brachytherapy
Abstract

Purpose Interstitial high-dose rate ( HDR) brachytherapy is an important therapeutic strategy for the treatment of locally advanced gynecologic ( GYN) cancers. The outcome of this therapy is determined by the quality of dose distribution achieved. This paper focuses on a novel yet simple heuristic for catheter selection for GYN HDR brachytherapy and their comparison against state of the art optimization strategies. The proposed technique is intended to act as a decision-supporting tool to select a favorable needle configuration. Materials The presented heuristic for catheter optimization is based on a shrinkage-type algorithm ( SACO). It is compared against state of the art planning in a retrospective study of 20 patients who previously received image-guided interstitial HDR brachytherapy using a Syed Neblett template. From those plans, template orientation and position are estimated via a rigid registration of the template with the actual catheter trajectories. All potential straight trajectories intersecting the contoured clinical target volume ( CTV) are considered for catheter optimization. Retrospectively generated plans and clinical plans are compared with respect to dosimetric performance and optimization time. Results All plans were generated with one single run of the optimizer lasting 0.6-97.4 s. Compared to manual optimization, SACO yields a statistically significant ( P ≤ 0.05) improved target coverage while at the same time fulfilling all dosimetric constraints for organs at risk ( OARs). Comparing inverse planning strategies, dosimetric evaluation for SACO and 'hybrid inverse planning and optimization' ( HIPO), as gold standard, shows no statistically significant difference ( P > 0.05). However, SACO provides the potential to reduce the number of used catheters without compromising plan quality. Conclusion The proposed heuristic for needle selection provides fast catheter selection with optimization times suited for intraoperative treatment planning. Compared to manual optimization, the proposed methodology results in fewer catheters without a clinically significant loss in plan quality. The proposed approach can be used as a decision support tool that guides the user to find the ideal number and configuration of catheters. [ABSTRACT FROM AUTHOR]

Published
2017
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