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1.

Purpose

The Radiation Oncology Incident Learning System (RO-ILS) receives event reports from facilities across the country. This effort extracted common error pathways seen in the data. These pathways, expressed as fault trees, demonstrate the need for, and opportunities for, preventing these errors and/or limiting their propagation to treatment.

Methods and materials

As of the third quarter of 2016, 2344 event reports had been submitted to RO-ILS and reviewed. A total of 396 of the reports judged highest priority were rereviewed and assigned up to 3 keywords to classify events. Based on patterns among the keyword assignments, the data were further aggregated into pathways leading to 3 general error types: “problematic plan approved for treatment,” “wrong shift instructions given to therapists,” and “wrong shift performed at treatment.” Fault trees were created showing how different errors at different stages in the treatment process combine to flow into these general error types.

Results

A total of 173 of the 396 (44%) events were characterized as belonging to 1 of these 3 general error types. Ninety-nine events were defined as “problematic plan approved for treatment,” 40 as “wrong shift instructions given to therapists,” and 34 as “wrong shift performed at treatment.” Seventy-six of these events (44%) resulted in incorrectly delivered treatment. Event discovery was by therapists (n = 76), physicists (n = 45), physicians (n = 23), dosimetrists (n = 15), or not identified (n = 9); 5 events were found as a result of the patient questioning the staff. For the event type “problematic plan approved for treatment,” 64 of the 99 (65%) events were attributable to physician error: incorrect target or dosing pattern prescribed.

Conclusions

Data extracted from RO-ILS event reports demonstrate common error pathways in radiation oncology that propagate all the way to treatment. Additional study and coordination of efforts is needed to develop and share best practices to address the sources of these errors and curtail their propagation.  相似文献   

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Purpose

We investigated the feasibility and accuracy of using carbon fiducials to localize the lumpectomy cavity with 2-dimensional kV imaging for early stage breast cancer radiation therapy.

Methods and Materials

Carbon fiducials were placed intraoperatively in the periphery of the lumpectomy cavity. Nine patients received whole breast irradiation with a boost, and 2 patients received 3-dimensional conformal partial breast irradiation. A total of 89 fractions were assessed for setup errors relative to a predefined gold standard, cone beam computed tomography (CBCT) match to the lumpectomy cavity, using the following 4 setup methods: (1) Align skin tattoos with lasers; (2) match bone with 2-dimensional–2-dimensional (2D/2D) kV onboard imaging (OBI); (3) match the whole breast with CBCT; and (4) match carbon fiducials with 2D/2D kV OBI. The margin for the planning target volume (PTV) was calculated by 2 standard deviations of the setup errors, and compared among the 4 setup methods. Setup errors for patients treated with free breathing and patients with deep inspiration breath hold were also compared.

Results

The carbon fiducials were sufficiently visible on OBI for matching and introduced minimal artifacts. Of the 4 alignment methods, 2D/2D OBI match to fiducials resulted in the smallest setup errors. The PTV margin was 12 mm for aligning skin tattoos using lasers, 9.2 mm for matching bone on OBI, 6.5 mm for matching breast on CBCT, and 3.5 mm for matching fiducials on 2D/2D OBI. Compared with free breathing, deep inspiration breath hold generally reduced the standard deviations of the setup errors, but further investigation would be needed.

Conclusions

Matching to carbon fiducials increased the localization accuracy to the lumpectomy cavity. This reduces residual setup error and PTV margins, facilitating tissue sparing without diminishing treatment efficacy.  相似文献   

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Purpose

This study aimed to evaluate dose calculation accuracy for the Eclipse Analytical Anisotropic Algorithm (AAA) and Acuros XB algorithm for various lung tumor sizes and to investigate dosimetric changes associated with treatment of regressing tumors.

Methods and materials

A water phantom with cylindrical cork inserts (lung surrogates) was fabricated. Large (202 cm3), medium (54 cm3), and small (3 cm3) solid water tumors were implanted within cork inserts. A plain cork insert was used to simulate a lung without a tumor. The cork inserts and tumors were cut along the long axis, and Gafchromic film was placed between the sections to measure dose distributions. Three-dimensional conformal plans were created using 6 MV and 10 MV beams, and volumetric modulated arc therapy plans were created using 6 MV beams for each tumor size. Doses were calculated using Eclipse AAA and Acuros XB. The measured and calculated dose distributions were compared for each tumor size and treatment algorithm. To simulate a regressing tumor, the original plans created for the large tumor were separately delivered to the phantom that contained a small, medium, or no tumor. The dosimetric effects were evaluated using gamma passing rates with a 2%/2 mm criterion and dose profile comparisons.

Results

Agreement between the measurements and AAA calculations decreased as tumor size decreased, but Acuros XB showed better agreement for all tumor sizes. The largest difference was observed for a 6 MV volumetric modulated arc therapy plan created to treat the smallest tumor. The gamma passing rate was 89.7% but that of Acuros was 99.5%. For the tumor regression evaluation, the gamma passing rates ranged from 53% to 99% for AAA. For Acuros XB, the gamma passing rates were >98% for all scenarios.

Conclusion

Both AAA and Acuros XB calculated the dose accurately for the largest lung tumor. For the smallest and regressing tumors, Acuros XB more accurately modelled the dose distribution compared with AAA.  相似文献   

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Prostate cancer–specific positron emission tomography (pcPET) has been shown to detect sites of disease recurrence at serum prostate-specific antigen (PSA) levels that are lower than those levels detected by conventional imaging. Commonly used pcPET radiotracers in the setting of biochemical recurrence are reviewed including carbon 11/fludeoxyglucose 18 (F-18) choline, gallium 68/F-18 prostate-specific membrane antigen (PSMA), and F-18 fluciclovine. Review of the literature generally favors PSMA-based agents for the detection of recurrence as a function of low PSA levels. Positive gallium 68/F-18 PSMA positron emission tomography/computed tomography scans detected potential sites of recurrence in a median 51.5% of patients when PSA level is <1.0 ng/mL, 74% of patients when PSA level is 1.0 to 2.0 ng/mL, and 90.5% of patients when PSA level is >2.0 ng/mL. Review of carbon 11/fludeoxyglucose 18 (F-18) choline and F-18 fluciclovine data commonly demonstrated lower detection rates for each respective PSA cohort, although with some important caveats, despite having similar operational characteristics to PSMA-based imaging. Sensitive pcPET imaging has provided new insight into the early patterns of disease spread, which has prompted judicious reconsideration of additional local therapy after either prostatectomy, definitive radiation therapy, or postprostatectomy radiation therapy. This review discusses the literature, clinical utility, availability, and fundamental understanding of pcPET imaging needed to improve clinical practice.  相似文献   

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BackgroundThis analysis was performed to describe the outcome of very elderly (≥ 80 years) patients with small-cell lung cancer (SCLC) as there is no published data regarding these patients.Materials and MethodsOne hundred forty-six very elderly patients with SCLC were identified from the Institutional Lung Cancer Database ranging in age from 80 to 92 years (median, 82 years). Of these, 47 (32%) patients had limited-stage SCLC (L-SCLC), and 99 (68%) had extensive-stage SCLC (E-SCLC). All were Caucasian, and the majority (64%) were female. Sixty-seven (46%) patients had Zubrod performance status (PS) of 0 to 1.ResultsOf the 146 patients, 44 (30%) received no therapy, 65 (45%) received chemotherapy alone, 27 (19%) received chemotherapy plus local therapy (thoracic radiotherapy [TRT] or surgery), and 10 (7%) received local therapy alone. The median survival was 5.4 months. On univariable analysis, age (P = .019), stage (L-SCLC vs. E-SCLC; P = .0002), PS (P < .0001), and treatment option (P < .0001) were associated with survival. On multivariable analysis, stage (P = .011), PS (P = .029), and treatment option (P < .0001) maintained significance. For entire cohort, the median survival was 1.3 months without active therapy, 6 months with local therapy alone, 7.2 months with chemotherapy alone, and 14.4 months with chemotherapy plus local therapy (P < .0001, univariable and multivariable). Similar survival findings in response to treatment were found when the L-SCLC and E-SCLC cohorts were separately analyzed.ConclusionsThe survival of very elderly patients with SCLC was associated with stage (L-SCLC vs. E-SCLC), PS, and treatment option. Very elderly patients with SCLC often have limited functional reserve required to tolerate aggressive multimodality therapy but appeared to benefit from it. Geriatric assessments, careful monitoring, and extra support are warranted in elderly patients. Care should be individualized based on the desires and needs of each patient.  相似文献   

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G S Rao  P Hanjani 《Cancer letters》1985,26(3):327-334
The association of a 97 kilodalton glycoprotein (97k-GP) with human ovarian epithelial tumors is reported. The 97k-GP has been found to be present in elevated levels in all the 8 serous cystadenocarcinoma specimens tested. This glycoprotein is present in small amounts in endometrial tumors and either absent or present in trace amounts in control ovaries. Subcellular localization of this glycoprotein indicates that it is a component of plasma membrane.  相似文献   

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Fungal prosthetic valve endocarditis is a rare but devastating disease. To better characterise this syndrome, we retrospectively reviewed 21 cases of fungal prosthetic valve endocarditis seen at Mayo Clinic over the past 40 years. The average patient age was 65 years with a 2 : 1 male predominance. Twelve of 21 cases (57%) occurred within 1 year of prosthetic valve placement. The aortic valve was most commonly affected, and the most common aetiological agent was Candida species, followed by Histoplasma capsulatum. Although 20 of 21 patients (95%) were immunocompetent, they had other risk factors for fungal infection. Patients typically presented with systemic signs and symptoms of infection, and cardiac imaging was abnormal in 68% of cases. Pathological evaluation of valve material was of high yield, with organisms identified in 92% of cases who underwent valve replacement surgery or had an autopsy performed. Prosthetic valve fungal endocarditis was associated with a high morbidity and mortality, with 67% of patients experiencing complications and 57% of patients dying of infection‐related disease. Hopefully, with the prompt institution of early medical therapy, surgical intervention and lifelong oral antifungal suppressive therapy, cure rates will continue to improve.  相似文献   

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BACKGROUND:

The Mayo Lung Project (MLP) was a randomized clinical trial designed to test whether periodic screening by chest x‐ray reduced lung cancer (LC) mortality in men who were high‐risk smokers. Among MLP participants, there were more deaths from LC in the screening arm both at the trial's end and after long‐term follow‐up. Overdiagnosis was cited widely as an explanation for the MLP results, whereas a role for excess LC risk attributable to undergoing numerous chest x‐ray screenings largely was unexamined. The authors of this report examined the consistency of the MLP data with a modified 2‐stage clonal expansion (TSCE) model of excess LC risk.

METHODS:

By using a simulation model calibrated to the initial MLP data, the authors examined the expected statistical variance of LC incidence and mortality between the screening and control arms. A Bayesian estimation framework using a modified version of the TSCE model to evaluate the role of excess LC risk attributable to chest x‐ray screening was derived and applied to the MLP data.

RESULTS:

Simulation experiments indicated that the overall difference in LC deaths and incidence between the study arm and the control arm was unlikely (P = .0424 and P = .0104, respectively) assuming no excess risk of LC. The authors estimated that the 10‐year excess LC risk for a man aged 60 years who smoked and who received 10 chest x‐ray screenings was 0.574% (P = .0021).

CONCLUSIONS:

The excess LC risk observed among screening arm participants was found to be statistically significant with respect to the TSCE model framework in part because of the incorporation of key risk correlates of age and screen frequency into the estimation framework. Cancer 2010. Published 2010 American Cancer Society  相似文献   

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Metastatic breast cancer frequently leads to brain metastases and, less commonly, leptomeningeal carcinomatosis (LC). Once cerebrospinal fluid involvement occurs, the prognosis is poor. There are limited treatment options available, but none offer significant survival benefit. Methotrexate, given systemically at high doses (3.5-8 gm/m2), achieves cytotoxic concentrations in the CSF and has been shown to prolong survival in patients with LC. Intrathecal liposomal cytarabine has been shown to increase time to neurologic progression in patients with breast cancer and LC. The combination of these 2 agents in LC has not been studied extensively. Here, we present the results of the phase II study with this combination showing promising efficacy and very good tolerability.  相似文献   

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