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1.
Am Surg ; 86(2): 90-94, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32167041

RESUMO

We aimed to evaluate the surgical margin outcomes and re-excision rates in patients undergoing bracketed seed localization of biopsy-proven breast cancer detected on screening mammogram. After approval by our Institutional Review Board, we retrospectively identified patients who had undergone iodine-125 seed localized lumpectomy at our institution from January 2010 to June 2017 by one of two fellowship-trained breast surgeons. Of those patients, a subset of 25 patients were identified who had undergone bracketed seed localization, defined as two or more seeds used to delineate the radiographic borders of the area of concern. All patients had originally presented with calcifications identified on screening mammogram that were subsequently diagnosed as ductal carcinoma in situ and/or invasive ductal carcinoma by image-guided biopsy performed at our institution. Eight patients had one positive margin on final surgical pathology and required re-excision (32%). One patient was converted to mastectomy. Of the patients requiring re-excision, the average maximum linear extent of calcifications was 3.4 cm (SD 0.97), whereas it was 3.1 cm (SD 1.2) in patients with negative surgical margins (P = 0.5). Bracketing calcifications with radioactive seeds can potentially allow more patients to undergo breast conservation surgery.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Radioisótopos do Iodo/administração & dosagem , Mastectomia Segmentar/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Feminino , Marcadores Fiduciais , Humanos , Biópsia Guiada por Imagem , Mamografia , Margens de Excisão , Reoperação/estatística & dados numéricos , Estudos Retrospectivos
2.
Br J Radiol ; 93(1107): 20190807, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003574

RESUMO

After years of lethargy, studies on two non-conventional microstructures in time and space of the beams used in radiation therapy are enjoying a huge revival. The first effect called "FLASH" is based on very high dose-rate irradiation (pulse amplitude ≥106 Gy/s), short beam-on times (≤100 ms) and large single doses (≥10 Gy) as experimental parameters established so far to give biological and potential clinical effects. The second effect relies on the use of arrays of minibeams (e.g., 0.5-1 mm, spaced 1-3.5 mm). Both approaches have been shown to protect healthy tissues as an endpoint that must be clearly specified and could be combined with each other (e.g., minibeams under FLASH conditions). FLASH depends on the presence of oxygen and could proceed from the chemistry of peroxyradicals and a reduced incidence on DNA and membrane damage. Minibeams action could be based on abscopal effects, cell signalling and/or migration of cells between "valleys and hills" present in the non-uniform irradiation field as well as faster repair of vascular damage. Both effects are expected to maintain intact the tumour control probability and might even preserve antitumoural immunological reactions. FLASH in vivo experiments involving Zebrafish, mice, pig and cats have been done with electron beams, while minibeams are an intermediate approach between X-GRID and synchrotron X-ray microbeams radiation. Both have an excellent rationale to converge and be applied with proton beams, combining focusing properties and high dose rates in the beam path of pencil beams, and the inherent advantage of a controlled limited range. A first treatment with electron FLASH (cutaneous lymphoma) has recently been achieved, but clinical trials have neither been presented for FLASH with protons, nor under the minibeam conditions. Better understanding of physical, chemical and biological mechanisms of both effects is essential to optimize the technical developments and devise clinical trials.


Assuntos
Tratamentos com Preservação do Órgão/métodos , Terapia com Prótons/métodos , Animais , Gatos , Proliferação de Células , Dano ao DNA , Reparo do DNA , Fracionamento da Dose de Radiação , Linfoma Cutâneo de Células T/radioterapia , Camundongos , Órgãos em Risco/efeitos da radiação , Oxigênio , Consumo de Oxigênio , Lesões por Radiação/prevenção & controle , Tolerância a Radiação , Radiometria/métodos , Neoplasias Cutâneas/radioterapia , Análise Espaço-Temporal , Suínos , Peixe-Zebra
3.
Br J Radiol ; 93(1107): 20190845, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904261

RESUMO

OBJECTIVES: The purpose of this study is to investigate the dosimetric effect and clinical impact of delivering a focal radiotherapy boost dose to multiparametric MRI (mp-MRI)-defined dominant intraprostatic lesions (DILs) in prostate cancer using proton therapy. METHODS: We retrospectively investigated 36 patients with pre-treatment mp-MRI and CT images who were treated using pencil beam scanning (PBS) proton radiation therapy to the whole prostate. DILs were contoured on co-registered mp-MRIs. Simultaneous integrated boost (SIB) plans using intensity-modulated proton therapy (IMPT) were created based on conventional whole-prostate-irradiation for each patient and optimized with additional DIL coverage goals and urethral constraints. DIL dose coverage and organ-at-risk (OAR) sparing were compared between conventional and SIB plans. Tumor control probability (TCP) and normal tissue complication probability (NTCP) were estimated to evaluate the clinical impact of the SIB plans. RESULTS: Optimized SIB plans significantly escalated the dose to DILs while meeting OAR constraints. SIB plans were able to achieve 125, 150 and 175% of prescription dose coverage in 74, 54 and 17% of 36 patients, respectively. This was modeled to result in an increase in DIL TCP by 7.3-13.3% depending on α/ß and DIL risk level. CONCLUSION: The proposed mp-MRI-guided DIL boost using proton radiation therapy is feasible without violating OAR constraints and demonstrates a potential clinical benefit by improving DIL TCP. This retrospective study suggested the use of IMPT-based DIL SIB may represent a strategy to improve tumor control. ADVANCES IN KNOWLEDGE: This study investigated the planning of mp-MRI-guided DIL boost in prostate proton radiation therapy and estimated its clinical impact with respect to TCP and NTCP.


Assuntos
Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Terapia com Prótons/métodos , Reirradiação/métodos , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Órgãos em Risco/efeitos da radiação , Próstata/diagnóstico por imagem , Próstata/efeitos da radiação , Neoplasias da Próstata/patologia , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Uretra/diagnóstico por imagem
4.
J Surg Oncol ; 121(3): 570-577, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31902136

RESUMO

BACKGROUND: Joint-preserving intercalary tumor resection can result in better proprioception and a more normal joint function after reconstruction. However, most reported reconstruction techniques are usually associated with frequent complications. Therefore, the approach of reconstruction following joint-preserving tumor resection warrants further study. METHODS: Between September 2016 and October 2018, 12 patients with metaphyseal malignant bone tumors around the knee joint were treated by joint-preserving intercalary resections with the aid of three-dimensional (3D)-printed osteotomy guide plates and reconstructions using 3D-printed intercalary prostheses. We assessed the accuracy of the resection by comparing the cross sections at the resection plane with 3D-printed matching surface of the prostheses. The functional outcomes, complications and oncological status were also evaluated. RESULTS: All patients were observed for 7 to 32 months with an average follow-up of 22.5 months. The achieved resection was accurate, with accurate matching between the residual bone and prosthesis. The mean MSTS score was 28 (range, 26-30). Superficial infection occurred in two patients. Local recurrence was observed in one patient, while pulmonary metastasis was identified in one patient. CONCLUSIONS: The personalized osteotomy guide plate and prosthesis based on 3D printing technique facilitate joint-preserving tumor resection and functional reconstruction. However, longer follow-up and larger sample size are required to clarify its long-term outcomes. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Doenças Ósseas/cirurgia , Neoplasias Ósseas/cirurgia , Articulação do Joelho/cirurgia , Tratamentos com Preservação do Órgão/métodos , Impressão Tridimensional/instrumentação , Implantação de Prótese , Procedimentos Cirúrgicos Reconstrutivos/métodos , Adolescente , Adulto , Neoplasias Ósseas/patologia , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteotomia , Prognóstico , Desenho de Prótese , Estudos Retrospectivos
5.
Int J Radiat Oncol Biol Phys ; 106(2): 440-448, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31928642

RESUMO

PURPOSE: Recent studies suggest that ultrahigh-dose-rate, "FLASH," electron radiation therapy (RT) decreases normal tissue damage while maintaining tumor response compared with conventional dose rate RT. Here, we describe a novel RT apparatus that delivers FLASH proton RT (PRT) using double scattered protons with computed tomography guidance and provide the first report of proton FLASH RT-mediated normal tissue radioprotection. METHODS AND MATERIALS: Absolute dose was measured at multiple depths in solid water and validated against an absolute integral charge measurement using a Faraday cup. Real-time dose rate was obtained using a NaI detector to measure prompt gamma rays. The effect of FLASH versus standard dose rate PRT on tumors and normal tissues was measured using pancreatic flank tumors (MH641905) derived from the KPC autochthonous PanCa model in syngeneic C57BL/6J mice with analysis of fibrosis and stem cell repopulation in small intestine after abdominal irradiation. RESULTS: The double scattering and collimation apparatus was dosimetrically validated with dose rates of 78 ± 9 Gy per second and 0.9 ± 0.08 Gy per second for the FLASH and standard PRT. Whole abdominal FLASH PRT at 15 Gy significantly reduced the loss of proliferating cells in intestinal crypts compared with standard PRT. Studies with local intestinal irradiation at 18 Gy revealed a reduction to near baseline levels of intestinal fibrosis for FLASH-PRT compared with standard PRT. Despite this difference, FLASH-PRT did not demonstrate tumor radioprotection in MH641905 pancreatic cancer flank tumors after 12 or 18 Gy irradiation. CONCLUSIONS: We have designed and dosimetrically validated a FLASH-PRT system with accurate control of beam flux on a millisecond time scale and online monitoring of the integral and dose delivery time structure. Using this system, we found that FLASH-PRT decreases acute cell loss and late fibrosis after whole-abdomen and focal intestinal RT, whereas tumor growth inhibition is preserved between the 2 modalities.


Assuntos
Órgãos em Risco/efeitos da radiação , Terapia com Prótons/instrumentação , Lesões Experimentais por Radiação/prevenção & controle , Proteção Radiológica/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Abdome/efeitos da radiação , Animais , Proliferação de Células/efeitos da radiação , Desenho de Equipamento/métodos , Estudos de Viabilidade , Feminino , Fibrose , Raios gama , Intestino Delgado/patologia , Intestino Delgado/efeitos da radiação , Camundongos , Camundongos Endogâmicos C57BL , Tratamentos com Preservação do Órgão/instrumentação , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/patologia , Neoplasias Pancreáticas/radioterapia , Terapia com Prótons/métodos , Proteção Radiológica/métodos , Radiometria/métodos , Radioterapia Guiada por Imagem/métodos , Espalhamento de Radiação , Células-Tronco/efeitos da radiação , Tomografia Computadorizada por Raios X
6.
Plast Reconstr Surg ; 145(2): 251e-262e, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31985611

RESUMO

BACKGROUND: The authors refine their anatomical patient selection criteria with a novel midclavicular-to-inframammary fold measurement for nipple-sparing mastectomy performed through an inframammary approach. METHODS: Retrospective review was performed of all nipple-sparing mastectomies performed through an inframammary approach. Exclusion criteria included other mastectomy incisions, staged mastectomy, previous breast operation, and autologous reconstruction. Preoperative anatomical measurements for each breast, clinical course, and specimen weight were obtained. RESULTS: One hundred forty breasts in 79 patients were analyzed. Mastectomy weight, but not sternal notch-to-nipple distance, was strongly correlated with midclavicular-to-inframammary fold measurement on linear regression (R = 0.651; p < 0.001). Mastectomy weight was not correlated with ptosis. Twenty-five breasts (17.8 percent) had ischemic complications: 16 (11.4 percent) were nonoperative and nine (6.4 percent) were operative. Those with mastectomy weights of 500 g or greater were nine times more likely to have operative ischemic complications than those with mastectomy weights less than 500 g (p = 0.0048). Those with a midclavicular-to-inframammary fold measurement of 30 cm or greater had a 3.8 times increased incidence of any ischemic complication (p = 0.00547) and a 9.2 times increased incidence of operative ischemic complications (p = 0.00376) compared with those whose midclavicular-to-inframammary fold measurement was less than 30 cm. CONCLUSIONS: Breasts undergoing nipple-sparing mastectomy by means of an inframammary approach with midclavicular-to-inframammary fold measurement greater than or equal to 30 cm are at higher risk for having ischemic complications, warranting consideration for a staged approach or other incision. The midclavicular-to-inframammary fold measurement is useful for assessing the entire breast and predicting the likelihood of ischemic complications in inframammary nipple-sparing mastectomies. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, III.


Assuntos
Neoplasias da Mama/cirurgia , Isquemia/etiologia , Mastectomia/métodos , Mamilos/cirurgia , Tratamentos com Preservação do Órgão/métodos , Adulto , Idoso , Feminino , Humanos , Incidência , Isquemia/epidemiologia , Modelos Logísticos , Mastectomia/efeitos adversos , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/efeitos adversos , Complicações Pós-Operatórias/etiologia , Análise de Regressão , Fatores de Risco
7.
Plast Reconstr Surg ; 145(2): 273e-283e, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31985614

RESUMO

BACKGROUND: Optimizing outcomes and assessing appropriate candidates for breast reconstruction after nipple-sparing mastectomy is an ongoing goal for plastic surgeons. METHODS: All patients undergoing nipple-sparing mastectomy from 2006 to June of 2018 were reviewed and randomly divided into test and validation groups. A logistic regression model calculating the odds ratio for any complication from 12 risk factors was derived from the test group, whereas the validation group was used to validate this model. RESULTS: The test group was composed of 537 nipple-sparing mastectomies (50.2 percent), with an overall complication rate of 27.2 percent (146 nipple-sparing mastectomies). The validation group was composed of 533 nipple-sparing mastectomies (49.8 percent), with an overall complication rate of 22.9 percent (122 nipple-sparing mastectomies). A logistic regression model predicting overall complications was derived from the test group. Nipple-sparing mastectomies in the test group were divided into deciles based on predicted risk in the model. Risk increased with probability decile; decile 1 was significantly protective, whereas deciles 9 and 10 were significantly predictive for complications (p < 0.0001). The relative risk in decile 1 was significantly decreased (0.39; p = 0.006); the relative risk in deciles 9 and 10 was significantly increased (2.71; p < 0.0001). In the validation group, the relative risk of any complication in decile 1 was decreased at 0.55 (p = 0.057); the relative risk in deciles 9 and 10 was significantly increased (1.89; p < 0.0001). In a receiver operating characteristic curve analysis, the area under the curve was 0.668 (p < 0.0001), demonstrating diagnostic meaningfulness of the model. CONCLUSION: The authors establish and validate a predictive risk model and calculator for nipple-sparing mastectomy with far-reaching impact for surgeons and patients alike.


Assuntos
Neoplasias da Mama/cirurgia , Mastectomia/efeitos adversos , Mamilos/cirurgia , Tratamentos com Preservação do Órgão/efeitos adversos , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Mastectomia/métodos , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Fatores de Risco
8.
Int J Radiat Oncol Biol Phys ; 106(3): 556-563, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31707122

RESUMO

PURPOSE: Surgery is standard treatment for rectal cancer, but neoadjuvant chemoradiation therapy (CRT) may result in clinical complete response (cCR) in select patients, allowing for nonsurgical management (NSM). Prospective studies of NSM strategies are sparse, however, and long-term data on quality of life (QoL) are limited. We conducted a single-arm phase 2 trial of high-dose CRT for NSM of distal rectal cancer; we report secondary long-term patient-reported outcomes (PROs), local regrowth, and overall survival in patients managed nonsurgically. METHODS AND MATERIALS: Fifty-one patients with resectable, T2 or T3, N0-N1, low adenocarcinoma received 65 Gy (intensity modulated radiation therapy, brachytherapy boost) and oral tegafur-uracil. Patients with cCR 6 weeks after treatment (clinical examination, magnetic resonance imaging, biopsy) were referred for observation and followed closely with clinical examination, endoscopy, positron emission tomography/computed tomography, and PROs for 5 years. Overall colorectal cancer-specific QoL and specific symptom scores were evaluated at baseline and in follow-up and compared between time points. Local regrowth was estimated using cumulative incidence and overall survival using Kaplan-Meier estimates. RESULTS: Forty patients achieved cCR after treatment; 29 were in follow-up at 24 months, 21 at 36 months, and 20 at 60 months. PRO questionnaire completion rates were 90% at 24 months, 100% at 36 months, and 85% at 60 months for patients still in follow-up. Average QoL score did not differ between baseline (median 11.1) and 24 months (13.7), 48 months (11.1), or 60 months (6.9). Only rectal bleeding deteriorated from baseline, with bowel- and bladder-related symptom scores otherwise unchanged in follow-up. At median follow-up of 5.0 years, local regrowth rate and overall survival were 31% (95% confidence interval, 15%-47%) and 85% (95% confidence interval, 75%-97%), respectively. CONCLUSIONS: Long-term follow-up after NSM of distal rectal cancer showed excellent general colorectal cancer QoL and local symptom scores. Our study results indicate that high-dose CRT followed by organ preservation might be an alternative to standard treatment.


Assuntos
Adenocarcinoma/terapia , Quimiorradioterapia Adjuvante/métodos , Tratamentos com Preservação do Órgão/métodos , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Neoplasias Retais/terapia , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Idoso , Braquiterapia/métodos , Intervalos de Confiança , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Dosagem Radioterapêutica , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia
9.
Int J Radiat Oncol Biol Phys ; 106(2): 430-439, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678227

RESUMO

PURPOSE: To evaluate whether automated knowledge-based planning (KBP) (a) is noninferior to human-driven planning across multiple disease sites and (b) systematically affects dosimetric plan quality and variability. METHODS AND MATERIALS: Clinical KBP automated planning routines were developed for prostate, prostatic fossa, hypofractionated lung, and head and neck. Clinical implementation consisted of independent generation of human-generated and KBP plans (145 cases across all sites), followed by blinded plan selection. Reviewing physicians were prompted to select a single plan; when plan equivalence was volunteered, this scored as KBP selection. Plan selection analysis used a noninferiority framework testing the hypothesis that KBP is not worse than human-driven planning (threshold: lower 95% confidence interval [CI] > 0.45 = noninferiority; > 0.5 = superiority). Target and organ-at-risk metrics were compared by dose differencing: ΔDx = Dx, human-Dx, KBP (2-tailed paired t test, Bonferroni-corrected P < .05 significance threshold). To evaluate the aggregated effect of KBP on planning performance, we examined post-KBP dosimetric parameters against 183 plans generated just before KBP implementation (2-tailed unpaired t test, Bonferroni-corrected P < .05). RESULTS: Across all disease sites, the KBP success rate (physician preferred + equivalent) was noninferior compared with human-driven planning (83 of 145 = 57.2%; range, 49.2%-65.3%) but did not cross the threshold for superiority. The KBP success rate in respective disease sites was superior with head and neck ([22 + 2]/36 = 66.7%; 95% CI, 51%-82%) and noninferior for lung stereotactic body radiation therapy ([21 + 2]/36 = 63.9%; 95% CI, 48%-80%) but did not meet noninferiority criteria with prostate ([16 + 3]/41 = 46.3%; 95% CI, 31%-62%) or prostatic fossa ([17 + 0]/32 = 53.1%; 95% CI, 36%-70%). Prostate, prostatic fossa, and head and neck showed significant differences in KBP-selected plans versus human-selected plans, with KBP generally exhibiting greater organ-at-risk sparing and human plans exhibiting better target homogeneity. Analysis of plan quality pre- and post-KBP showed some reductions in organ doses and quality metric variability in prostate and head and neck. CONCLUSIONS: Fully automated KBP was noninferior to human-driven plan optimization across multiple disease sites. Dosimetric analysis of treatment plans before and after KBP implementation showed a systematic shift to higher plan quality and lower variability with the introduction of KBP.


Assuntos
Protocolos Clínicos , Neoplasias de Cabeça e Pescoço/radioterapia , Gestão do Conhecimento , Neoplasias Pulmonares/radioterapia , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Bases de Conhecimento , Neoplasias Pulmonares/patologia , Masculino , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco , Neoplasias da Próstata/patologia , Garantia da Qualidade dos Cuidados de Saúde , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/normas , Equipolência Terapêutica
10.
Int J Radiat Oncol Biol Phys ; 106(3): 621-629, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759074

RESUMO

PURPOSE: Preclinical research into ultrahigh dose rate (eg, ≥40 Gy/s) "FLASH"-radiation therapy suggests a decrease in side effects compared with conventional irradiation while maintaining tumor control. When FLASH is delivered using a scanning proton beam, tissue becomes subject to a spatially dependent range of dose rates. This study systematically investigates dose rate distributions and delivery times for proton FLASH plans using stereotactic lung irradiation as the paradigm. METHODS AND MATERIALS: Stereotactic lung radiation therapy FLASH-plans, using 244 MeV scanning proton transmission beams, with the Bragg peak behind the body, were made for 7 patients. Evaluated parameters were dose rate distribution within a beam, overall irradiation time, number of times tissue is irradiated, and quality of the FLASH-plans compared with the clinical volumetric-modulated arc therapy (VMAT) plans. RESULTS: Sparing of lungs, thoracic wall, and heart in the FLASH-plans was equal to or better than that in the VMAT-plans. For a spot peak dose rate (SPDR, the dose rate in the middle of the spot) of 100 Gy/s, ∼40% of dose is delivered at FLASH dose rates, and for SPDR = 360 Gy/s this increased to ∼75%. One-hundred percent FLASH dose rate cannot be achieved owing to small contributions from distant spots with lower dose rates. The total irradiation time varied between 300 to 730 ms, and around 85% of the dose-receiving body volume was irradiated by either 1 or 2 beams. CONCLUSIONS: Clinical implementation of FLASH using scanning proton beams requires multiple treatment planning considerations: dosimetric, temporal, and spatial parameters all seem important. The FLASH efficiency of a scanning proton beam increases with SPDR. The methodology proposed in this proof-of-principle study provides a framework for evaluating the FLASH characteristics of scanning proton beam plans and can be adapted as FLASH parameters are better defined. It currently seems logical to optimize plans for the shortest delivery time, maximum amount of high dose rate coverage, and maximum amount of single beam and continuous irradiation.


Assuntos
Neoplasias Pulmonares/radioterapia , Terapia com Prótons/métodos , Radiocirurgia/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Coração , Humanos , Pulmão , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco , Estudo de Prova de Conceito , Terapia com Prótons/efeitos adversos , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Medula Espinal , Parede Torácica , Fatores de Tempo
11.
Int J Radiat Oncol Biol Phys ; 106(3): 630-638, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759076

RESUMO

PURPOSE: Intensity modulated proton therapy (IMPT) of locally advanced prostate cancer can spare the bowel considerably compared with modern photon therapy, but simultaneous treatment of the prostate (p), seminal vesicles (sv), and lymph nodes is challenging owing to day-to-day organ motion and range uncertainties. Our purpose was, therefore, to generate a plan library for use in adaptive IMPT to mitigate these uncertainties. METHODS AND MATERIALS: We retrospectively included 27 patients with a series of computed tomography scans throughout their treatment representing day-to-day variation. In 18 of the patients, target motion was analyzed using rigid shifts of prostate gold markers relative to bony anatomy. A plan library with different p and sv planning target volume (p/sv-PTV) positions was defined from the distribution and direction of these shifts. Delivery of IMPT using plan selection from the library was simulated for image guidance on bony anatomy, in the remaining patients and compared with nonadaptive IMPT. RESULTS: The plan library consisted of 3 small margin p/sv-PTVs: (1) p/sv-PTV shifted 1.5 systematic error (Σ) of the population mean in the anterior and cranial directions, (2) p/sv-PTV shifted 1.5Σ in the posterior and caudal directions, and (3) p/sv-PTV in the planning position. The conventional p/sv-PTV was also available for backup. Plan selection compared with nonadaptive IMPT resulted in a reduction of the rectum volume receiving 60 Gy relative biological effect (RBE) (V60GyRBE) from on average 12 mL to 9 mL. For the bladder the average V45GyRBE was reduced from 36% to 30%. Large and small bowel doses were also reduced, whereas target coverage was comparable or improved compared with nonadaptive IMPT. CONCLUSIONS: Plan selection based on a population model of rigid target motion was feasible for all patients. Compared with conventional IMPT, plan selection resulted in significant dosimetric sparing of rectum and bladder without compromising target coverage.


Assuntos
Movimentos dos Órgãos , Neoplasias da Próstata/radioterapia , Terapia com Prótons/métodos , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada/métodos , Pontos de Referência Anatômicos/diagnóstico por imagem , Marcadores Fiduciais , Ouro , Humanos , Bibliotecas Digitais , Linfonodos/diagnóstico por imagem , Irradiação Linfática/métodos , Masculino , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Próstata/diagnóstico por imagem , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Reto/diagnóstico por imagem , Estudos Retrospectivos , Glândulas Seminais/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Incerteza , Bexiga Urinária/diagnóstico por imagem
12.
Br J Radiol ; 93(1107): 20190378, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31430188

RESUMO

Radiation therapy is an essential component of treatment for locally advanced non-small cell lung cancer (NSCLC) but can be technically challenging because of the proximity of lung tumors to nearby critical organs or structures. The most effective strategy for reducing radiation-induced toxicity is to reduce unnecessary exposure of normal tissues by using advanced technology; examples from photon (X-ray) therapy have included three-dimensional conformal radiation therapy versus its predecessor, two-dimensional radiation therapy, and intensity-modulated photon radiation therapy versus its predecessor, three-dimensional conformal therapy. Using particle-beam therapy rather than photons offers the potential for further advantages because of the unique depth-dose characteristics of the particles, which can be exploited to allow still higher dose escalation to tumors with greater sparing of normal tissues, with the ultimate goal of improving local tumor control and survival while preserving quality of life by reducing treatment-related toxicity. However, the costs associated with particle therapy with protons are considerably higher than the current state of the art in photon technology, and evidence of clinical benefit from protons is increasingly being demanded to justify the higher financial burden on the healthcare system. Some such evidence is available from preclinical studies, from retrospective, single-institution clinical series, from analyses of national databases, and from single-arm prospective studies in addition to several ongoing randomized comparative trials. This review summarizes the rationale for and challenges of using proton therapy to treat thoracic cancers, reviews the current clinical experience, and suggests topics for future research.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Órgãos em Risco/efeitos da radiação , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Radioterapia de Intensidade Modulada/métodos , Carcinoma Pulmonar de Células não Pequenas/patologia , Previsões , Humanos , Neoplasias Pulmonares/patologia , Tratamentos com Preservação do Órgão/métodos , Estudos Prospectivos , Terapia com Prótons/economia , Terapia com Prótons/tendências , Qualidade de Vida , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/economia , Radioterapia de Intensidade Modulada/tendências , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Resultado do Tratamento
13.
World Neurosurg ; 133: e412-e420, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31536811

RESUMO

OBJECTIVE: The cervical extensor musculature is important in cases of neck pain and loss of cervical lordosis after laminoplasty. Therefore, various surgical methods have been developed to preserve the muscle during laminoplasty. We have developed a posterior cervical muscle-preserving interspinous process (MIS) approach and decompression method. We have described the operation details and clinical outcomes of selected patients who have undergone this procedure. METHODS: The MIS approach and decompression method were performed in 20 consecutive patients who had only required central decompression for cervical stenosis. This procedure includes an approach to the interspinous space that is similar to Shiraishi's method but includes decompression without fracturing the spina bifida. RESULTS: The patients had no complications and did not require conversion to conventional laminoplasty. The mean operative time and mean blood loss was 53.0 minutes and 63.0 mL per level, respectively, and the mean hospital stay was 4.0 days. The mean preoperative and 3-month postoperative modified Japanese Orthopedic Association scores were 12.6 and 16.2, and the mean preoperative and 3-month postoperative neck disability index scores were 15.4 and 2.5, respectively. The postoperative neck visual analog scale score was 0.8. The mean preoperative and postoperative sagittal vertical axis was 1.6 and 1.8 cm, respectively. The mean loss of lordosis was 1.0°, and the mean cervical range of motion did not change from preoperatively to postoperatively. CONCLUSIONS: The MIS approach and decompression method was less invasive than both conventional laminoplasty and Shiraishi's selective laminectomy. It is a safe and effective minimally invasive technique for central stenosis caused by cervical spondylotic myelopathy.


Assuntos
Vértebras Cervicais/cirurgia , Laminectomia/métodos , Músculos do Pescoço/cirurgia , Procedimentos Neurocirúrgicos/métodos , Tratamentos com Preservação do Órgão/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Laminectomia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/efeitos adversos , Satisfação do Paciente , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/cirurgia , Estenose Espinal/cirurgia , Adulto Jovem
14.
Int J Radiat Oncol Biol Phys ; 106(1): 194-205, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31610250

RESUMO

PURPOSE: To develop and validate combined ion-beam with constant relative biological effectiveness (RBE) (CICR) particle therapy in single field arrangements for improved treatment efficacy, robustness, and normal tissue sparing. METHODS AND MATERIALS: The PRECISE (PaRticle thErapy using single and Combined Ion optimization StratEgies) treatment planning system was developed to investigate clinical viability of CICR treatments. Single-field uniform dose (SFUD) with a single ion (proton [p], helium [He], or carbon [C]) and CICR (C-p and C-He) treatments were generated for 3 patient cases with a clinically prescribed dose of 3 Gy (RBE) per fraction. Spread-out Bragg peak plans were irradiated in homogenous and clinical-like settings using an anthropomorphic head phantom. A dosimetric and biological verification of CICRC-p treatments using a murine glioma cell line (GL261) was performed. RESULTS: CICR treatment plans for the 3 patients presented highly uniform physical dose while reducing high dose-averaged linear energy transfer gradients compared with carbon ions alone. When considering uncertainty in tissue parameter (α/ß)x assignment and RBE modeling, the CICRC-p treatment exhibited enhanced biophysical stability within the target volume, similar to protons alone. CICR treatments reduced dose to normal tissue surrounding the target, exhibiting similar or improved dosimetric features compared with SFUDHe. For both CICRC-p and SFUD treatments, measurements verified the planned dose in the target within ∼3%. Planned versus measured target RBE values were 1.38 ± 0.02 and 1.39 ± 0.07 (<1% deviation), respectively, for the CICRC-p treatment in heterogenous settings. CONCLUSIONS: Here, we demonstrate that by combining 2 (or more) ions in a single field arrangement, more robust biological and more conformal dose distributions can be delivered compared with conventional particle therapy treatment planning. This work constitutes the first dosimetric and biological verification of multi-ion particle therapy in homogeneous as well as heterogenous settings.


Assuntos
Neoplasias Encefálicas/radioterapia , Carcinoma Adenoide Cístico/radioterapia , Cordoma/radioterapia , Glioma/radioterapia , Radioterapia com Íons Pesados/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias da Coluna Vertebral/radioterapia , Animais , Neoplasias Encefálicas/diagnóstico por imagem , Carbono/uso terapêutico , Carcinoma Adenoide Cístico/diagnóstico por imagem , Linhagem Celular Tumoral , Cordoma/diagnóstico por imagem , Terapia Combinada/métodos , Fracionamento da Dose de Radiação , Glioma/diagnóstico por imagem , Hélio/uso terapêutico , Humanos , Transferência Linear de Energia , Camundongos , Órgãos em Risco , Imagens de Fantasmas , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador , Eficiência Biológica Relativa , Sacro , Neoplasias da Coluna Vertebral/diagnóstico por imagem
15.
Bone Joint J ; 101-B(11): 1438-1446, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31674243

RESUMO

AIMS: This study aimed to explore whether intraoperative nerve monitoring can identify risk factors and reduce the incidence of nerve injury in patients with high-riding developmental dysplasia. PATIENTS AND METHODS: We conducted a historical controlled study of patients with unilateral Crowe IV developmental dysplasia of the hip (DDH). Between October 2016 and October 2017, intraoperative nerve monitoring of the femoral and sciatic nerves was applied in total hip arthroplasty (THA). A neuromonitoring technician was employed to monitor nerve function and inform the surgeon of ongoing changes in a timely manner. Patients who did not have intraoperative nerve monitoring between September 2015 and October 2016 were selected as the control group. All the surgeries were performed by one surgeon. Demographics and clinical data were analyzed. A total of 35 patients in the monitoring group (ten male, 25 female; mean age 37.1 years (20 to 46)) and 56 patients in the control group (13 male, 43 female; mean age 37.9 years (23 to 52)) were enrolled. The mean follow-up of all patients was 13.1 months (10 to 15). RESULTS: The two groups had no significant differences in preoperative data. In the monitoring group, ten nerve alerts occurred intraoperatively, and no neural complications were detected postoperatively. In the control group, six patients had neural complications. The rate of nerve injury was lower in the monitoring group than in the control group, but this did not achieve statistical significance. The degree of leg lengthening was significantly greater in the monitoring group than in the control group. In further analyses, patients who had previous hip surgery were more likely to have intraoperative nerve alerts and postoperative nerve injury. CONCLUSION: Nerve injury usually occurred during the processes of exposure and reduction. The use of intraoperative nerve monitoring showed a trend towards reduced nerve injury in THA for Crowe IV DDH patients. Hence, we recommend its routine use in patients undergoing leg lengthening, especially in those with previous hip surgery. Cite this article: Bone Joint J 2019;101-B:1438-1446.


Assuntos
Artroplastia de Quadril/métodos , Nervo Femoral/fisiologia , Luxação Congênita de Quadril/cirurgia , Tratamentos com Preservação do Órgão/métodos , Nervo Isquiático/fisiologia , Adulto , Feminino , Nervo Femoral/lesões , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/métodos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/prevenção & controle , Estudos Prospectivos , Nervo Isquiático/lesões , Traumatismos do Sistema Nervoso/prevenção & controle , Adulto Jovem
16.
Medicine (Baltimore) ; 98(44): e17742, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689824

RESUMO

Placenta previa and accreta with prior cesarean section is an extremely serious condition that is associated with maternal morbidity and mortality from obstetric hemorrhage. The aim of our study was to evaluate the efficacy and advantages of a novel surgical technique, parallel transverse uterine incisions (PTUI), during conservative cesarean delivery in patients with placenta previa and accreta.This was a retrospective cohort study including 124 pregnant women, who had at least 1 prior cesarean section and were diagnosed with anterior placenta previa and accreta between January 2014 and October 2017. Using the hospital's information system, patients were retrospectively classified into undergoing either the PTUI surgery (Group A) or the ordinary cesarean section (Group B). Surgical outcomes and maternal complications during hospitalization were collected. The results from 2 groups were compared and analyzed statistically. Multivariable regression analyses were further used to assess the effect of PTUI on severe maternal outcomes.Patients who underwent PTUI were not statistically different from patients who underwent the ordinary cesarean section in terms of maternal and infants' characteristics. However, PTUI was associated with remarkably reduced intraoperative blood loss (P = .005), related vaginal blood loss after surgery (P = .026), and transfusion requirement of packed red cells (P = .000), compared to the ordinary cesarean section. Moreover, cesarean hysterectomy (3.3% vs 21.9%; P = .002) and intensive care unit admission (1.7% vs 29.7%; P = .000) were significantly fewer among patients who underwent PTUI. Multivariable regression analyses further showed that the risk of intraoperative hemorrhage (ß = -2343.299, P = .000) and cesarean hysterectomy (odds ratio = 0.027, P = .018) were both significantly decreased by PTUI.PTUI is a novel approach that may significantly reduce maternal complications, while preserving the uterus for patients with anterior placenta previa and accreta.


Assuntos
Cesárea/métodos , Histerectomia/métodos , Histeroscopia/métodos , Tratamentos com Preservação do Órgão/métodos , Placenta Acreta/cirurgia , Placenta Prévia/cirurgia , Hemorragia Pós-Parto/cirurgia , Adulto , Perda Sanguínea Cirúrgica , Transfusão de Sangue/estatística & dados numéricos , Cesárea/efeitos adversos , Feminino , Humanos , Histerectomia/efeitos adversos , Hemorragia Pós-Parto/etiologia , Gravidez , Estudos Retrospectivos , Resultado do Tratamento , Útero/cirurgia
17.
Artigo em Inglês | MEDLINE | ID: mdl-31751008

RESUMO

Malignant pleural mesothelioma is a cancer of the mesothelial cells lining the pleural sac. Surgery for malignant pleural mesothelioma should be part of a multimodality treatment approach and the aim of surgery should be macroscopic complete tumor resection. Lung-sparing operations, such as extended pleurectomy decortication, have gained increasing popularity in the past decade.  This video tutorial illustrates the main steps of extended pleurectomy decortication for the treatment of malignant pleural mesothelioma.


Assuntos
Neoplasias Pulmonares , Pulmão , Mesotelioma , Pleura/cirurgia , Neoplasias Pleurais , Procedimentos Cirúrgicos Torácicos/métodos , Idoso , Dissecação/métodos , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Mesotelioma/patologia , Mesotelioma/cirurgia , Tratamentos com Preservação do Órgão/métodos , Pleura/patologia , Neoplasias Pleurais/patologia , Neoplasias Pleurais/cirurgia , Resultado do Tratamento
18.
Artigo em Inglês | MEDLINE | ID: mdl-31751009

RESUMO

Minimally invasive pulmonary segmentectomy allows adequate oncologic treatment in selected cases while preserving lung parenchyma and minimizing perioperative morbidity and length of hospital stay.  Most lung segments can be resected as segmentectomies or as part of bisegmentectomies (as is the case for the lingula). However, the resection of individual basal segments can be particularly challenging. Although several variations of minimally invasive pulmonary segmentectomy have been described, I favor a fully thoracoscopic multiport approach that offers direct access to the segmental structures, and is straightforward and versatile enough to allow for adaptation in case of unexpected intraoperative findings (such as conversion to lobectomy in the case of positive margins). Key aspects of anterobasal segmentectomy include proper patient positioning, appropriate positioning of operating trocars, standardized technique to expose and dissect the segmental artery and bronchus, and accurate division of the intersegmental plane.


Assuntos
Neoplasias Colorretais/patologia , Nódulos Pulmonares Múltiplos , Neoplasias Primárias Múltiplas/patologia , Pneumonectomia/métodos , Toracoscopia/métodos , Idoso , Humanos , Masculino , Mastectomia Segmentar , Nódulos Pulmonares Múltiplos/patologia , Nódulos Pulmonares Múltiplos/cirurgia , Tratamentos com Preservação do Órgão/métodos , Posicionamento do Paciente/métodos
19.
World J Gastroenterol ; 25(36): 5494-5504, 2019 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-31576095

RESUMO

BACKGROUND: Laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) was known to have benefits of function-preserving surgery compared to laparoscopy-assisted distal gastrectomy (LADG). However, in clinical settings, delayed gastric emptying and esophageal reflux following LAPPG can be serious issues, making surgeons reluctant to perform LAPPG. It is unclear that LAPPG had better long-term functional outcomes and quality of life compared to LADG. AIM: To evaluate the long-term functional outcomes and patient-reported quality of life of LAPPG compared to those of LADG. METHODS: We reviewed the clinicopathological data of 195 patients who underwent LADG with Billroth II anastomosis and 101 patients who underwent LAPPG for cT1N0 gastric cancer in the middle third of the stomach between 2012 and 2015. Postoperative complications, nutritional parameters, and survey results of the European Organization for Research and Treatment of Cancer Questionnaire C30 and STO22 questionnaire were compared between the two groups. RESULTS: The serum hemoglobin level was significantly higher in the LAPPG group than in the LADG group (P < 0.001). In the endoscopic findings, incidence of bile reflux was lower (P < 0.001); however, the incidence of residual food was higher in the LAPPG group than in the LADG group (P < 0.001). Regarding the quality of life score, the LAPPG group had a better physical functioning score (86.7 vs 90.0, P = 0.032) but also greater pain and reflux when compared to the LADG group [8.3 vs 16.7 in pain, 11.1 (interquartile range, 0, 22.2) vs 11.1 (interquartile range, 11.1, 33.3) in reflux, P = 0.034 and 0.001, respectively]. CONCLUSION: LAPPG is beneficial to recovery of anemia and to bile reflux, however, it might be unfavorable in terms of pain and reflux symptoms compared to LADG with Billroth II anastomosis.


Assuntos
Gastrectomia/efeitos adversos , Refluxo Gastroesofágico/epidemiologia , Laparoscopia/métodos , Tratamentos com Preservação do Órgão/efeitos adversos , Dor Pós-Operatória/epidemiologia , Piloro/cirurgia , Neoplasias Gástricas/cirurgia , Adulto , Idoso , Feminino , Gastrectomia/métodos , Gastroenterostomia/efeitos adversos , Gastroenterostomia/métodos , Refluxo Gastroesofágico/etiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tratamentos com Preservação do Órgão/métodos , Medição da Dor , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Qualidade de Vida , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Resultado do Tratamento
20.
Niger J Clin Pract ; 22(10): 1396-1402, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31607729

RESUMO

Background: Nephron-sparing surgery (NSS) is currently the recommended treatment modality for selected renal tumors. The prognostic significance of positive surgical margin (PSM) and surgical margin width (SMW) after NSS is controversial. Aim: To evaluate the effect of PSM and SMW on cancer-specific survival (CSS) in patients who underwent NSS. Materials and Methods: The pathological samples of 142 patients who underwent NSS were reviewed. Patients were divided into two groups with PSM and negative surgical margin (NSM), and after that those with PSM were divided into two groups according to SMW as those with 0.1-2 mm and those >2 mm. CSS was calculated using Kaplan-Meier method. Cox regression analysis was used to adjust the clinicopathologic variables. A P value < 0.05 was considered statistically significant. Results: Local recurrence rate and distant metastasis rate were higher in patients with PSMs than those with NSMs (P = 0.018 and P = 0.039, respectively). However, there was no significant difference between the two groups in terms of CSS. In the group with SMW 0.1-2 mm, the tumor diameter was longer (P = 0.018), enucleation number was higher (P = 0.026), and local recurrence was higher (P = 0.034) than the group with SMW > 2 mm. There was no significant difference between the two groups in terms of CSS. Conclusion: In patients who underwent NSS, PSMs and SMWs have a negative effect on local recurrence but have no significant effect on CSS.


Assuntos
Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/mortalidade , Neoplasias Renais/cirurgia , Margens de Excisão , Recidiva Local de Neoplasia/mortalidade , Nefrectomia/mortalidade , Néfrons/cirurgia , Tratamentos com Preservação do Órgão/mortalidade , Tratamentos com Preservação do Órgão/métodos , Idoso , Carcinoma de Células Renais/patologia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/cirurgia , Nefrectomia/efeitos adversos , Nefrectomia/métodos , Néfrons/patologia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
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