Publications by authors named "Clara Choi"
Hyponatremia, a common electrolyte disorder, usually has a benign clinical course. However, patients with the syndrome of inappropriate antidiuretic hormone secretion (SIADH) can suffer unfavorable outcomes, including mortality. Atypical antipsychotics, which are among the drugs associated with SIADH, also cause tardive dyskinesia, a condition that physicians can now effectively manage with the recently approved agent - valbenazine.
View Article and Find Full Text PDFBackground: This study examined the relationships between compensation, willingness to keep same career path, and burnout among long-term care workers in Japan.
Methods: Data were collected from 319 care workers at long-term care facilities in Japan. The study variables included data on demographics, compensation, willingness to keep same career path, and burnout.
Purpose: Thoracoscopic esophageal atresia with tracheo-esophageal fistula (EA/TEF) repair requires the gentle manipulation of delicate tissue. Force sensors were attached to the upper and lower esophagus of a 3D-printed EA/TEF simulator to explore force parameters as markers of performance.
Methods: Participants completed one intracorporeal suture between the anterior walls of upper and lower esophageal ends.
Purpose: In patients with newly diagnosed glioblastoma (GBM), tumor margins of at least 20 mm are the standard of care. We sought to determine the pattern of tumor progression in patients treated with 5-fraction stereotactic radiosurgery with 5-mm margins.
Methods And Materials: Thirty adult patients with newly diagnosed GBM were treated with 5-fraction stereotactic radiosurgery in escalated doses from 25 to 40 Gy with a 5-mm total treatment margin.
Introduction: Acquiring the technical skills required for thoracoscopic repair of esophageal atresia with tracheo-esophageal fistula (EA/TEF) is challenging. A high-fidelity 3D-printed pediatric thoracoscopic EA/TEF simulator has been developed to address this issue. This study explored motion-tracking as an assessment tool to distinguish between surgeons of different expertise using the simulator.
View Article and Find Full Text PDFObjectives: We investigated differences in quality of life (QoL) in patients enrolled on a phase I/II dose-escalation study of 3-fraction resection cavity stereotactic radiosurgery (SRS) for large brain metastases.
Methods: Eligible patients had 1 to 4 brain metastases, one of which was a resection cavity 4.2 to 33.
Background: We sought to determine the maximum tolerated dose (MTD) of 5-fraction stereotactic radiosurgery (SRS) with 5-mm margins delivered with concurrent temozolomide in newly diagnosed glioblastoma (GBM).
Methods: We enrolled adult patients with newly diagnosed glioblastoma to 5 days of SRS in a 3 + 3 design on 4 escalating dose levels: 25, 30, 35, and 40 Gy. Dose limiting toxicity (DLT) was defined as Common Terminology Criteria for Adverse Events grades 3-5 acute or late CNS toxicity, including adverse radiation effect (ARE), the imaging correlate of radiation necrosis.
The development of cavernous malformations many years following conventionally fractionated brain irradiation is well recognized and commonly reported. However, cavernous malformation induction following stereotactic radiosurgery (SRS) is largely unreported. Herein, we describe two cases of cavernous malformation formation years following SRS for brain metastases.
View Article and Find Full Text PDFPurpose: To determine the maximum tolerated dose (MTD) of vorinostat, a histone deacetylase inhibitor, given concurrently with stereotactic radiosurgery (SRS) to treat non-small cell lung cancer (NSCLC) brain metastases. Secondary objectives were to determine toxicity, local failure, distant intracranial failure, and overall survival rates.
Materials And Methods: In this multicenter study, patients with 1 to 4 NSCLC brain metastases, each ≤2 cm, were enrolled in a phase 1, 3 + 3 dose escalation trial.
Purpose: We report a longitudinal assessment of health-related quality of life (HRQOL) in patients with glioblastoma (GBM) treated on a prospective dose escalation trial of 5-fraction stereotactic radiosurgery (25-40 Gy in 5 fractions) with concurrent and adjuvant temozolomide.
Methods: HRQOL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) quality of life questionnaire core-30 (QLQ-C30) general, the EORTC quality of life questionnaire-brain cancer specific module (QLQ-BN20), and the M.D.
Aim: Sarcoidosis is a multisystem granulomatous disease. This condition has a documented association with the diagnosis of melanoma and can be induced in melanoma patients receiving anti-neoplastic therapy. We evaluated a case series of melanoma patients who developed immunotherapy-induced sarcoidosis.
View Article and Find Full Text PDFNon-vestibular cranial nerve schwannomas (NVCNS) are rare lesions, representing <10 % of cranial nerve schwannomas. The optimal treatment for NVCNS is often derived from vestibular schwannomas experience. Surgical resection has been referred to as the first line treatment for those benign tumors, but significant complication rates are reported.
View Article and Find Full Text PDFObjective: Recurrent World Health Organization (WHO) grade II and III meningiomas have traditionally been treated by surgery alone, but early literature suggests that adjuvant stereotactic radiosurgery may greatly improve outcomes. We present the long-term tumor control and safety of a hypofractionated stereotactic radiosurgery regimen.
Methods: Prospectively collected data of 44 WHO grade II and 9 WHO grade III meningiomas treated by CyberKnife for adjuvant or salvage therapy were reviewed.
Patients with tumors adjacent to the optic nerves and chiasm are frequently not candidates for single-fraction stereotactic radiosurgery (SRS) due to concern for radiation-induced optic neuropathy. However, these patients have been successfully treated with hypofractionated SRS over 2-5 days, though dose constraints have not yet been well defined. We reviewed the literature on optic tolerance to radiation and constructed a dose-response model for visual pathway tolerance to SRS delivered in 1-5 fractions.
View Article and Find Full Text PDFPurpose: To report the outcomes of repeat stereotactic radiosurgery (SRS), deferring whole-brain radiation therapy (WBRT), for distant intracranial recurrences and identify factors associated with prolonged overall survival (OS).
Patients And Methods: We retrospectively identified 652 metastases in 95 patients treated with 2 or more courses of SRS for brain metastases, deferring WBRT. Cox regression analyzed factors predictive for OS.
Purpose: Current craniospinal irradiation (CSI) protocols do not include the parotid gland as an organ at risk, potentially leading to late effects of xerostomia and secondary parotid malignancies. We analyzed the effect of CSI treatment parameters on parotid dose.
Materials And Methods: We retrospectively reviewed 50 consecutive patients treated with CSI to an intracranial dose >26 Gy.
Purpose: We sought to determine the risk of leptomeningeal disease (LMD) in patients treated with stereotactic radiosurgery (SRS) targeting the postsurgical resection cavity of a brain metastasis, deferring whole-brain radiation therapy (WBRT) in all patients.
Methods And Materials: We retrospectively reviewed 175 brain metastasis resection cavities in 165 patients treated from 1998 to 2011 with postoperative SRS. The cumulative incidence rates, with death as a competing risk, of LMD, local failure (LF), and distant brain parenchymal failure (DF) were estimated.
Background: An alternative treatment option to whole-brain irradiation after surgical resection of brain metastases is resection cavity stereotactic radiosurgery (SRS).
Objective: To review the dynamics of cavity volume change after surgical resection with the goal of determining the optimal timing for cavity SRS.
Methods: Preresection tumor, postresection/pre-SRS cavity, and post-SRS cavity volumes were measured for 68 cavities in 63 patients treated with surgery and postresection cavity SRS.
Objective: Paragangliomas (PGs) or glomus tumors are rare, and publications comparing treatment alternatives are few. We sought to analyze our experience with stereotactic radiosurgery (SRS), review the literature, and develop treatment guidelines.
Methods: We retrospectively examined the outcomes of 41 PGs in 36 patients treated with SRS at Stanford.
Purpose: Given the neurocognitive toxicity associated with whole-brain irradiation (WBRT), approaches to defer or avoid WBRT after surgical resection of brain metastases are desirable. Our initial experience with stereotactic radiosurgery (SRS) targeting the resection cavity showed promising results. We examined the outcomes of postoperative resection cavity SRS to determine the effect of adding a 2-mm margin around the resection cavity on local failure (LF) and toxicity.
View Article and Find Full Text PDFObjective: For multisession radiosurgery, no published data relate the volume and dose of cochlear irradiation to quantified risk of hearing loss. We conducted a retrospective, dosimetric study to evaluate the relationship between hearing loss after stereotactic radiosurgery (SRS) and the dose-volume of irradiated cochlea.
Methods: Cochlear dose data were retrospectively collected on consecutive patients who underwent SRS (18 Gy in 3 sessions) for vestibular schwannoma between 1999 and 2005 at Stanford University Hospital.
What is the optimal treatment of large brain metastases? An argument for a multidisciplinary approach.
Int J Radiat Oncol Biol Phys
November 2012
Purpose: Single-modality treatment of large brain metastases (>2 cm) with whole-brain irradiation, stereotactic radiosurgery (SRS) alone, or surgery alone is not effective, with local failure (LF) rates of 50% to 90%. Our goal was to improve local control (LC) by using multimodality therapy of surgery and adjuvant SRS targeting the resection cavity.
Patients And Methods: We retrospectively evaluated 97 patients with brain metastases >2 cm in diameter treated with surgery and cavity SRS.
Purpose: To assess the role of a planned neck dissection (PND) after sequential chemoradiotherapy for patients with head-and-neck cancer with N2-N3 nodal disease.
Methods And Materials: We reviewed 90 patients with N2-N3 head-and-neck squamous cell carcinoma treated between 1991 and 2001 on two sequential chemoradiotherapy protocols. All patients received induction and concurrent chemotherapy with cisplatin and 5-fluorocuracil, with or without tirapazamine.
Background: The role of stereotactic radiosurgery in the treatment of benign intracranial lesions is well established. Although a growing body of evidence supports its role in the treatment of malignant spinal lesions, a much less extensive dataset exists for treatment of benign spinal tumors.
Objective: To examine the safety and efficacy of stereotactic radiosurgery for treatment of benign, intradural extramedullary spinal tumors.
Background: Single-session stereotactic radiosurgery (SRS) treatment of vestibular schwannomas results in excellent tumor control. It is not known whether functional outcomes can be improved by fractionating the treatment over multiple sessions.
Objective: To examine tumor control and complication rates after multisession SRS.