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1.
Strahlenther Onkol ; 200(2): 123-127, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37264179

RESUMO

PURPOSE: The purpose of this study was to investigate the feasibility and effectiveness of high-dose planned adaptive intensity-modulated radiation therapy (IMRT) with helical tomotherapy (HT) for cutaneous angiosarcoma (cAS) of the scalp. METHODS: This retrospective cross-sectional included a total of 12 consecutive patients with cAS of the scalp who underwent high-dose planned adaptive IMRT with HT. Prescribed doses were 72.5-74 Gy in 35-37 fractions for the gross tumor volume plus a 1-2 mm margin (PTV1), 58-60 Gy in 29-30 fractions for the clinical target volume plus a 2-3 mm margin (PTV2), and 46 Gy in 23 fractions for the clinical target volume plus a 5-15 mm margin (PTV3) over periods of 7.5, 6 and 4.5 weeks, respectively. RESULTS: The estimated 1­year and 2­year overall survival rate were 65.6% and 27.3%, respectively, and the local progression-free survival at 2 years was 74.1%. All local recurrences were either in or marginal to the PTV2 or PTV3. No local recurrence was observed in the PTV1. All patients tolerated the treatment without grade 3 or higher adverse events during the radiotherapy period. No late adverse events were observed during the follow-up period. CONCLUSION: Planned adaptive high-dose IMRT with HT has the potential to improve local control rate without increasing adverse events.


Assuntos
Hemangiossarcoma , Radioterapia de Intensidade Modulada , Humanos , Dosagem Radioterapêutica , Hemangiossarcoma/radioterapia , Planejamento da Radioterapia Assistida por Computador , Couro Cabeludo , Estudos Transversais , Estudos Retrospectivos
2.
Acta Radiol ; 64(4): 1439-1442, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36221814

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) findings after subcutaneous extravasation of gadolinium-based contrast agent (GBCA) have not been investigated in detail. PURPOSE: To present the MRI findings of iatrogenic extravasation and to evaluate the characteristic findings. MATERIAL AND METHODS: In this retrospective study of 16,039 patients with cancer, 11 patients had significant extravasation of macrocyclic GBCA, and 7 of the 11 had MRI of the injection site. Characteristic MRI findings as well as symptoms and changes over time were evaluated. RESULTS: The forearms or antecubital fossa felt cold in all seven cases, and 3 (43%) patients felt pain at the injection sites. Fat-suppressed T1-weighted images showed a mosaic pattern of the extravasate with mixed high and low signal in the subcutaneous tissue in 7 (100%) cases. Contrast enhancement of the fascia toward the proximal portion was observed in 3 (43%) cases. There was no subfascial deep extension. On T2-weighted images, GBCAs were observed as low-signal fluid collection on the fascia, with linear spread to the dermis and subcutaneous tissue. Four patients underwent daily MRI scans, all of whom had their contrast disappeared within three days. CONCLUSION: Macrocyclic GBCA disappears from subcutaneous tissue quickly after extravasation and is unlikely to cause serious sequelae.


Assuntos
Neoplasias , Compostos Organometálicos , Humanos , Meios de Contraste/efeitos adversos , Gadolínio/efeitos adversos , Gadolínio DTPA , Estudos Retrospectivos , Compostos Organometálicos/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Neoplasias/diagnóstico por imagem , Doença Iatrogênica , Encéfalo
3.
Cancer Invest ; 40(5): 437-441, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35236196

RESUMO

The purpose of this study was to investigate the efficacy and feasibility of high-dose (72.6 Gy) planned adaptive intensity-modulated radiation therapy (IMRT) with simultaneous integrated boost (SIB) for 9 consecutive patients with synchronous oligometastatic pancreatic ductal adenocarcinoma (PDAC). The estimated 2-year overall survival rate was 66.7%, and the local progression-free survival at 2 years was 83.3%. No severe adverse events were observed. Planned adaptive dose-escalated IMRT-SIB has the potential to improve local control rate and prolong overall survival in patients with synchronous oligometastatic PDAC.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Radioterapia de Intensidade Modulada , Carcinoma Ductal Pancreático/radioterapia , Humanos , Neoplasias Pancreáticas/radioterapia , Intervalo Livre de Progressão , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos
4.
Rep Pract Oncol Radiother ; 27(5): 842-847, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36523793

RESUMO

Background: Endorectal balloon (ERB) has been shown to reduce rectal radiation dose and late gastrointestinal toxicities in patients with prostate cancer. However, the usefulness of ERBs for patients with prostate cancer whose rectal shape or size is suboptimal has not been investigated. The purpose of this study was to present the long-term follow-up results of ERB-assisted helical tomotherapy for localized prostate cancer patients whose initial radiation treatment planning (RTP) was unacceptable due to suboptimal rectal shape or size. Materials and methods: Of 541 consecutive patients with localized prostate cancer, 10 were included in this study whose RTPs without ERBs did not meet dose constraints due to: 1) Intestinal intrusion, 2) Small rectum; or 3) Unstable rectal shape. We re-planned using ERBs and delivered 76 Gy in 38 fractions, and evaluated the long-term usefulness and safety of ERB-assisted helical tomotherapy. Results: At a median follow-up of 109 months, there were no local recurrences of prostate cancer. The overall, cause-specific, and progression-free survivals at 10 years were 90.0%, 100%, and 83%, respectively. Adverse events of grade 3 or higher were not observed during or after ERB-assisted helical tomotherapy. Conclusions: When intestinal intrusion, a small rectum, or an unstable rectal shape is an obstacle for administering helical tomotherapy, ERBs might be the solution.

5.
Rep Pract Oncol Radiother ; 26(3): 470-474, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34277103

RESUMO

BACKGROUND: MRI-guided radiation therapy can image a target and irradiate it at the same time. Superparamagnetic iron oxide (SPIO) is a liver-specific contrast agent that can selectively visualize liver tumors, even if plain MRI does not depict them. The purpose of this study was to present a proof of concept of SPIO-enhanced MRI-guided radiation therapy for liver tumor. CASE PRESENTATION: MRI-guided stereotactic ablative radiation therapy (SABR) was planned for a patient with impaired renal function who developed liver metastases after nephroureterectomy for ureteral cancer. Because liver metastasis was not visualized on plain MRI, SPIO-enhanced MRI was performed at 0.35 T using true fast imaging with steady-state free precession (true FISP) pulse sequence and SABR was performed. Liver metastasis was clearly visualized by SPIO-enhanced MRI, and MRI-guided SABR was performed without adverse events. CONCLUSION: Even if liver metastasis is not visualized by plain MRI, liver metastasis can be clearly depicted by administering SPIO, and MRI-guided radiation therapy can be performed.

6.
J Radiosurg SBRT ; 9(2): 129-133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39087063

RESUMO

Purpose: Despite the efficacy of endorectal balloon (ERB) in reducing rectal radiation dose, the effectiveness of upper rectal fixation remains to be evaluated. The purpose of this study was to evaluate the impact of ERB on upper rectal fixation in patients diagnosed with localized prostate cancer. Materials: Cine MRI was performed in 46 patients with localized prostate cancer to assess the stability of the anterior rectal wall with and without ERB by calculating the standard deviation of the normalized signal intensity at the level of the midgland or the seminal vesicle. Results: The standard deviation of the normalized signal intensity for the anterior rectal wall decreased significantly with the use of ERB both at the level of the midgland (p < 0.05) and the seminal vesicle (p < 0.05). The standard deviation of the anterior rectal wall at the level of the seminal vesicle was significantly higher than at the level of the midgland without ERB (p < 0.05). But with ERB, the standard deviation of the normalized signal intensity at the level of the seminal vesicle became comparable to that at the level of the midgland (p = 0.392). Conclusion: The anterior rectal wall is stabilized by ERBs not only at the level of the midgland but also at the level of the seminal vesicle. ERBs can transform the rectum from a moving and deformable organ into a static and rigid organ.

7.
Acta Oncol ; 51(6): 730-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22132747

RESUMO

BACKGROUND: There is no current consensus regarding the optimal bladder volumes in definitive radiotherapy for localized prostate cancer. The aim of this study was to clarify the relationship between the bladder volume and optimal treatment planning in radiotherapy for localized prostate cancer. MATERIAL AND METHODS: Two hundred and forty-three patients underwent definitive radiotherapy with helical tomotherapy for intermediate- and high-risk localized prostate cancer. The prescribed dose defined as 95% of the planning target volume (PTV) receiving ≧ 100% of the prescription dose was 76 Gy in 38 fractions. The clinical target volume (CTV) was defined as the prostate with a 5-mm margin and 2 cm of the proximal seminal vesicle. The PTV was defined as the CTV with a 5-mm margin. Treatment plans were optimized to satisfy the dose constraints defined by in-house protocols for PTV and organs at risk (rectum wall, bladder wall, sigmoid colon and small intestine). If all dose constraints were satisfied, the plan was defined as an optimal plan (OP). RESULTS: An OP was achieved with 203 patients (84%). Mean bladder volume (± 1 SD) was 266 ml (± 130 ml) among those with an OP and 214 ml (±130 ml) among those without an OP (p = 0.02). Logistic regression analysis also showed that bladder volumes below 150 ml decreased the possibility of achieving an OP. However, the percentage of patients with an OP showed a plateau effect at bladder volumes above 150 ml. CONCLUSIONS: Bladder volume is a significant factor affecting OP rates. However, our results suggest that bladder volumes exceeding 150 ml may not help meet planning dose constraints.


Assuntos
Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador , Bexiga Urinária/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Prognóstico , Neoplasias da Próstata/patologia
8.
J Appl Clin Med Phys ; 13(1): 3700, 2012 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-22231222

RESUMO

In this paper, we suggest a new method for verifying the motion of a binary multileaf collimator (MLC) in helical tomotherapy. For this we used a combination of a cylindrical scintillator and a general-purpose camcorder. The camcorder records the light from the scintillator following photon irradiation, which we use to track the motion of the binary MLC. The purpose of this study is to demonstrate the feasibility of this method as a binary MLC quality assurance (QA) tool. First, the verification was performed using a simple binary MLC pattern with a constant leaf open time; secondly, verification using the binary MLC pattern used in a clinical setting was also performed. Sinograms of simple binary MLC patterns, in which leaves that were open were detected as "open" from the measured light, define the sensitivity which, in this case, was 1.000. On the other hand, the specificity, which gives the fraction of closed leaves detected as "closed", was 0.919. The leaf open error identified by our method was -1.3 ± 7.5%. The 68.6% of observed leaves were performed within ± 3% relative error. The leaf open error was expressed by the relative errors calculated on the sinogram. In the clinical binary MLC pattern, the sensitivity and specificity were 0.994 and 0.997, respectively. The measurement could be performed with -3.4 ± 8.0% leaf open error. The 77.5% of observed leaves were performed within ± 3% relative error. With this method, we can easily verify the motion of the binary MLC, and the measurement unit developed was found to be an effective QA tool.


Assuntos
Radioterapia Conformacional/instrumentação , Radioterapia Guiada por Imagem/instrumentação , Contagem de Cintilação/instrumentação , Gravação em Vídeo/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Retroalimentação , Movimento (Física) , Dosagem Radioterapêutica , Rotação
9.
Br J Radiol ; 95(1135): 20211131, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35333542

RESUMO

OBJECTIVES: The purpose of this study was to investigate the changes of tumor-to-liver signal ratio in a 0.35T MRI-guided radiotherapy system and to evaluate the usefulness and pitfalls of superparamagnetic iron oxide (SPIO) administration for visualization of liver tumors. METHODS: Forty-two patients treated with MRI-guided stereotactic ablative radiotherapy (SABR) for liver tumors were included in this study. The tumor-to-liver signal ratios before and after SPIO administration were retrospectively assessed and compared on true fast imaging with steady-state precession (FISP). RESULTS: Before SPIO administration, liver tumors were either invisible or barely visible in 15 cases (36%), but all tumors became visible after SPIO administration. The mean values of tumor-to-liver signal ratio before and after SPIO administration were 0.939 ± 0.201 and 1.336 ± 0.300, respectively (mean ± standard deviation, p < 0.001). In six (14%) patients, liver tumors were visible on true FISP imaging before SPIO administration, but became invisible after administration. CONCLUSIONS: This study showed that liver tumors that are invisible on true FISP imaging can be made visible by administration of SPIO, and that MRI-guided SABR can be performed accurately. ADVANCES IN KNOWLEDGE: This is the first report to examine the usefulness of liver-specific contrast agent superparamagnetic iron oxides in 0.35T MRI-guided radiation therapy. Liver tumors that are invisible on true fast imaging with steady-state precession can be made visible by administration of superparamagnetic iron oxides.


Assuntos
Neoplasias Hepáticas , Nanopartículas de Magnetita , Meios de Contraste , Dextranos , Compostos Férricos , Humanos , Ferro , Fígado/diagnóstico por imagem , Fígado/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/radioterapia , Imageamento por Ressonância Magnética/métodos , Óxidos , Estudos Retrospectivos
10.
J Radiosurg SBRT ; 8(2): 105-108, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36275133

RESUMO

Purpose: There are no detailed data on volume changes of SpaceOAR hydrogel spacer. The purpose of this study was to quantitatively evaluate the volume changes of SpaceOAR during radiation therapy for prostate cancer. Materials: The volume of SpaceOAR in seven prostate cancer patients was quantitatively measured every two weeks by Dixon-based water-only MRI scans. Results: The volume of SpaceOAR increased and remained increased for 11 weeks after placement in all cases. The day to reach the maximum volume was 49.9 +/- 9.2 (mean +/- standard deviation [SD]) days after placement. The maximum rate of increase in Space OAR volume was 20% +/- 9% (mean +/- SD). Conclusions: The volume of SpaceOAR was shown to be greater than the initial volume for 11 weeks after placement, with an increase of up to 20%. Therefore, care should be taken when creating a radiation treatment planning and positioning a patient during radiation therapy.

11.
J Cancer Res Ther ; 18(Supplement): S489-S492, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36511012

RESUMO

A 69-year-old man with a history of pancreatic cancer was referred to our hospital for a newly developed solitary liver metastasis. Since the liver metastasis was in contact with the small intestine, it was necessary to perform radiation therapy while simultaneously monitoring the small intestine and liver metastasis, and then, MRI-guided stereotactic ablative radiation therapy (SABR) was performed. There were no radiation-induced adverse events during the treatment and 6 months of follow-up. MRI showed complete regression of the tumor at 6 months after SABR. It seems feasible to perform SABR safely by using MRI-guided radiation therapy system even if liver metastasis developed near the intestinal tract after surgery for pancreatic cancer.


Assuntos
Neoplasias Hepáticas , Neoplasias Pancreáticas , Radiocirurgia , Masculino , Humanos , Idoso , Radiocirurgia/efeitos adversos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/diagnóstico por imagem , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/etiologia , Imageamento por Ressonância Magnética , Neoplasias Pancreáticas
12.
Anticancer Res ; 42(1): 329-334, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34969741

RESUMO

BACKGROUND/AIM: This study investigated the feasibility and efficacy of multiparametric magnetic resonance imaging (MRI)-guided dose-escalated hypofractionated intensity-modulated radiation therapy with simultaneous integrated boost (IMRT-SIB) for glioblastoma. PATIENTS AND METHODS: Eighteen patients underwent postoperative IMRT-SIB for glioblastoma using three MRI sequences: double inversion recovery (DIR), diffusion tensor imaging (DTI), and post-gadolinium T1-weighted imaging. Prescribed doses were 60 Gy and 40 Gy in 15 fractions for residual enhancing lesions and surrounding tumor-infiltrating areas, respectively. For surrounding tumor-infiltrating areas, asymmetric margins were set with reference to DTI imaging. RESULTS: The 1-year overall survival rate was 58.0%, and the 1-year local control rate for the residual enhancing lesions was 76.2%, while that for surrounding tumor-infiltrating areas was 39.4%. One patient (6%) developed grade 2 cerebral radiation necrosis 10 months after IMRT-SIB, but there was no grade 3 or higher adverse event. CONCLUSION: Multiparametric MRI-guided dose-escalated IMRT-SIB with DIR and DTI imaging has the potential to improve local control rates without increasing adverse events.


Assuntos
Glioblastoma/radioterapia , Hipofracionamento da Dose de Radiação , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Adulto , Idoso , Imagem de Tensor de Difusão/normas , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética Multiparamétrica/normas , Taxa de Sobrevida
13.
Adv Radiat Oncol ; 7(3): 100851, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35647399

RESUMO

Purpose: Concern about a long-term effect of the delivery of intensity modulated radiation therapy (IMRT) for prostate cancer on serum testosterone levels remains unelucidated. We evaluated how IMRT for localized prostate cancer affects serum testosterone levels during a follow-up period of up to 10 years. Methods and Materials: We retrospectively evaluated data from 182 patients with localized prostate cancer who underwent definitive IMRT alone between 2007 and 2014. Serum total testosterone (TT) levels were measured by blood draws between 6 AM and 11 AM before treatment and at every posttreatment follow-up for 10 years. Pretreatment values and each posttreatment testosterone value were compared using a Wilcoxon signed rank test. The data set was stratified into 4 groups based on the pretreatment testosterone (pre-TT) values using quartiles. Results: The median absolute or relative changes in TT levels from pretreatment were -0.42 ng/mL or -12.0% at 3 months after radiation therapy (P < .0001). Subsequently, TT levels gradually recovered to nearly the pretreatment levels 24 to 36 months after IMRT. When analyzed according to the pre-TT quartile, median TT levels initially decreased at the 3- to 12-month period in all the quartiles; however, median TT levels increased from the 18-month period in the first and second quartile groups, whereas they were maintained at less than the pretreatment levels in the third and the fourth quartile groups throughout the entire decade after radiation therapy. The proportion of patients with hypogonadal status, defined as TT levels <3.00 ng/mL, did not increase over time. Conclusions: A transient and modest decrease of TT levels after IMRT spontaneously recovered to the pretreatment levels at the 24- to 36-month period except in patients in the higher quartile of pre-TT. This might have been partly owing to a variable sensitivity of individual testicular function to scattered radiation. Patients with lower pre-TT did not demonstrate a progressive overall rate of hypogonadism until 10 years after radiation therapy.

14.
Radiat Oncol ; 17(1): 146, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35996192

RESUMO

BACKGROUND: Magnetic resonance-guided radiotherapy (MRgRT) utilization is rapidly expanding, driven by advanced capabilities including better soft tissue imaging, continuous intrafraction target visualization, automatic triggered beam delivery, and the availability of on-table adaptive replanning. Our objective was to describe patterns of 0.35 Tesla (T)-MRgRT utilization in Europe and Asia among early adopters of this novel technology. METHODS: Anonymized administrative data from all 0.35T-MRgRT treatment systems in Europe and Asia were extracted for patients who completed treatment from 2015 to 2020. Detailed treatment information was analyzed for all MR-linear accelerators (linac) and -cobalt systems. RESULTS: From 2015 through the end of 2020, there were 5796 completed treatment courses delivered in 46,389 individual fractions. 23.5% of fractions were adapted. Ultra-hypofractionated (UHfx) dose schedules (1-5 fractions) were delivered for 63.5% of courses, with 57.8% of UHfx fractions adapted on-table. The most commonly treated tumor types were prostate (23.5%), liver (14.5%), lung (12.3%), pancreas (11.2%), and breast (8.0%), with increasing compound annual growth rates (CAGRs) in numbers of courses from 2015 through 2020 (pancreas: 157.1%; prostate: 120.9%; lung: 136.0%; liver: 134.2%). CONCLUSIONS: This is the first comprehensive study reporting patterns of utilization among early adopters of a 0.35T-MRgRT system in Europe and Asia. Intrafraction MR image-guidance, advanced motion management, and increasing adoption of on-table adaptive RT have accelerated a transition to UHfx regimens. MRgRT has been predominantly used to treat tumors in the upper abdomen, pelvis and lungs, and increasingly with adaptive replanning, which is a radical departure from legacy radiotherapy practices.


Assuntos
Radiocirurgia , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Aceleradores de Partículas , Radiocirurgia/métodos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos
15.
Strahlenther Onkol ; 186(11): 637-42, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21069269

RESUMO

BACKGROUND AND PURPOSE: To evaluate variation in bladder volume of full bladders in definitive radiotherapy for localized prostate cancer and to investigate potential predictors of increased bladder volume variations. PATIENTS AND METHODS: In 40 patients, the bladder volume was measured with megavoltage computed tomography (MVCT) imaging performed just before irradiation during the administration of the 1st fraction (#1), the 10th fraction (#10), the 20th fraction (#20), and the 30th fraction (#30). Patients were instructed to avoid urinating for 60-90 minutes before the planning CT (pln-CT) scan and before daily irradiation. Patients were also encouraged to drink an unspecified volume of liquid that would result in a clear but tolerable urge to urinate. RESULTS: The population-mean bladder volume (±1SD) was 219 ml (±83 ml) at the planning CT scan (pln-CT), 186 ml (±96 ml) at #1, 149 ml (±73 ml) at #10, 137 ml (±59 ml) at #20, and 136 ml (±60 ml) at #30. The mean intrapatient variation in bladder volume (1 SD relative to the mean bladder volume of each patient) was 38% (range: 10-84%). The bladder volume at the pln-CT was correlated with the intrapatient variance in bladder volume with a correlation coefficient of 0.54 and p <0.001. CONCLUSION: We observed a significant decline in bladder volumes during the course of radiotherapy. The bladder volume at the pln-CT was a significant predictor of increased bladder volume variations.


Assuntos
Neoplasias da Próstata/radioterapia , Lesões por Radiação/etiologia , Radioterapia de Intensidade Modulada , Bexiga Urinária/efeitos da radiação , Urodinâmica/efeitos da radiação , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/uso terapêutico , Cistite/etiologia , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Doses de Radiação , Planejamento da Radioterapia Assistida por Computador , Tomografia Computadorizada de Feixe Cônico Espiral/métodos , Estatística como Assunto
16.
Int Cancer Conf J ; 9(2): 52-54, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32257753

RESUMO

Pancytopenia is a rare complication among patients with breast cancer. Here, we report a case of pancytopenia due to massive bone marrow carcinomatosis (BMC) developed after local radiotherapy following to mastectomy. A 48-year-old woman with locally advanced breast cancer underwent mastectomy and axillary lymph node dissection. During adjuvant chemotherapy, rapidly growing supraclavicular lymph node metastasis was noted, so chemotherapy was discontinued and local radiotherapy was performed. There was no myelosuppression or systemic metastases prior to radiotherapy, but 2 weeks after the completion of radiotherapy, complete blood counts showed pancytopenia, and chest CT scans revealed multiple bone metastasis. A bone marrow biopsy was performed and massive BMC was diagnosed. Despite the best supportive care, her disease progressed rapidly and she died 2 months after radiotherapy. Locally advanced breast cancer that is resistant to chemotherapy is at risk of early fatal BMC and should be carefully monitored.

17.
BJR Open ; 2(1): 20200010, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178974

RESUMO

OBJECTIVE: To assess the difference in gross tumor volumes (GTVs) defined by CT (GTV-CT) and by low magnetic field strength (0.345 T) MRI (GTV-MRI) in patients simulated for MRI-guided radiotherapy forlung metastasis. METHODS: 28 patients (148 lesions) who underwent CT and MRI simulation with the tri-60Co MRI-guided radiotherapy system (MRIdian, ViewRay) were included in this study. GTV-CT and GTV-MRI were compared using the paired t-test. The equivalence of variance between GTV-CT and GTV-MRI of small lesions (GTV-CT <1 ml) and large ones (GTV-CT >= 1 ml) was evaluated using F-test. The correlation between GTV-CT and GTV-MRI was evaluated by the correlation coefficient. RESULTS: GTV-MRI was 120% larger than GTV-CT (p < 0.001) for small lesions, whereas GTV-MRI was 40% larger than GTV-CT (p < 0.001) for large lesions. In small lesions, the variation in GTV-MRI was significantly larger than that of GTV-CT (p < 0.001). There was no significant difference in the variation of GTV-MRI and GTV-CT in large lesions (p = 0.121). The correlation coefficient for small lesions was 0.93, whereas that for large lesions was 0.99, with large lesions having better correlation. CONCLUSIONS: GTV-MRI was larger than GTV-CT and the correlation between GTV-MRI and GTV-CT was better in large lesions. If the tumor volume is 1 ml or larger, the lesion can be accurately monitored even with a low magnetic field strength MRI. ADVANCES IN KNOWLEDGE: This study is the first clinical report to evaluate the tolerability of MRI images in 0.345 T MRI-guided radiotherapy for lung metastasis. GTV contoured by MRI was larger than GTV by CT, and this tendency was more pronounced in small tumors of less than 1 ml.

18.
Int J Clin Oncol ; 14(4): 356-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19705248

RESUMO

A 62-year-old woman presented with right flank pain, and computed tomography (CT) showed bilateral adrenal tumors (right, 8 cm; left, 4 cm). There were no abnormal findings on physical examination, and adrenal hormone levels in serum and urine were within normal limits. Radiological studies showed a right adrenal tumor with intratumoral hemorrhage, a cystic tumor in the left adrenal gland, and no sign of distant metastasis. Because laboratory tests showed normal levels of adrenal hormones, we considered the tumors to be nonfunctioning adrenal tumors. The right adrenal tumor was surgically removed because it was thought to be malignant, and histological examination revealed that it was a leiomyosarcoma. Postoperative CT showed a pleural metastasis in the right chest wall. The patient received combination chemotherapy with cyclophosphamide, vincristine, adriamycin, and dacarbazine. The metastasis was also treated with radiofrequency ablation (RFA). Because the left adrenal tumor grew rapidly despite two courses of the chemotherapy, it too was surgically removed. After the operation, metastasis in the right iliac bone was treated with RFA and radiotherapy. Positron emission tomography detected bilateral femoral metastases, and these were treated with radiotherapy in combination with a low dose of cisplatin. A liver metastasis and a small metastasis in the left kidney were treated with RFA and a metastasis in the pancreatic tail was removed surgically. Sixteen months after the right adrenalectomy, the patient died due to systemic spread of the disease. Multiple local treatments including RFA, radiotherapy, and resection were effective for the local control of metastatic lesions of adrenal leiomyosarcoma.


Assuntos
Neoplasias das Glândulas Suprarrenais/terapia , Adrenalectomia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ablação por Cateter , Leiomiossarcoma/terapia , Neoplasias das Glândulas Suprarrenais/patologia , Adulto , Idoso , Biópsia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Quimioterapia Adjuvante , Evolução Fatal , Feminino , Humanos , Neoplasias Renais/secundário , Neoplasias Renais/terapia , Leiomiossarcoma/secundário , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/secundário , Neoplasias Pancreáticas/terapia , Neoplasias Pleurais/secundário , Neoplasias Pleurais/terapia , Tomografia por Emissão de Pósitrons , Radioterapia Adjuvante , Tomografia Computadorizada por Raios X , Resultado do Tratamento
19.
Cancer Res ; 67(8): 3809-17, 2007 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-17440095

RESUMO

Optical probes that yield high target-to-background ratios are necessary to detect microfoci of cancer that would otherwise escape detection with white light imaging. Target-specific activation of the optical signal at tumor foci is one mechanism by which high target and low background signal can be achieved. Here, we describe a two-step activation process in which the tumors are first pretargeted with a nonfluorescent biotinylated monoclonal antibody [cetuximab (Erbitux) targeting human epidermal growth factor receptor type 1 (HER1)]. Following this, a second agent, neutravidin-BODIPY-FL fluorescent conjugate, is given and binds to the previously targeted antibody, resulting in an approximately 10-fold amplification of the optical fluorescence signal, leading to high tumor-to-background ratios. Spectral fluorescence imaging was done in a mouse model of peritoneal metastasis using a HER1-overexpressing cell line (A431) after pretargeting with biotinylated cetuximab and 3 h after administration of neutravidin-conjugated BODIPY-FL. Both aggregated tumors as well as small cancer implants were clearly visualized in vivo. For lesions approximately 0.8 mm or greater in diameter, the spectral fluorescence imaging had a sensitivity of 96% (178 of 185) and a specificity of 98% (188 of 191). This two-step activation paradigm (pretargeting followed by neutravidin-biotin binding with an attached activatable fluorophore) could be useful in tumor-specific molecular imaging of various targets to guide surgical resections.


Assuntos
Anticorpos Monoclonais/metabolismo , Avidina/metabolismo , Corantes Fluorescentes/metabolismo , Imunoconjugados/metabolismo , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados , Avidina/química , Biotinilação , Compostos de Boro/química , Compostos de Boro/metabolismo , Cetuximab , Receptores ErbB/imunologia , Citometria de Fluxo , Corantes Fluorescentes/química , Humanos , Imunoconjugados/química , Microscopia de Fluorescência , Neoplasias Peritoneais/imunologia , Neoplasias Peritoneais/patologia , Sensibilidade e Especificidade
20.
Cancer Res ; 67(6): 2791-9, 2007 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-17363601

RESUMO

A target cell-specific activation strategy for improved molecular imaging of peritoneal implants has been proposed, in which fluorophores are activated only in living targeted cells. A current example of an activatable fluorophore is one that is normally self-quenched by attachment to a peptide backbone but which can be activated by specific proteases that degrade the peptide resulting in "dequenching." In this study, an alternate fluorescence activation strategy is proposed whereby self-quenching avidin-rhodamine X, which has affinity for lectin on cancer cells, is activated after endocytosis and degradation within the lysosome. Using this approach in a mouse model of peritoneal ovarian metastases, we document target-specific molecular imaging of submillimeter cancer nodules with minimal contamination by background signal. Cellular internalization of receptor-ligand pairs with subsequent activation of fluorescence via dequenching provides a generalizable and highly sensitive method of detecting cancer microfoci in vivo and has practical implications for assisting surgical and endoscopic procedures.


Assuntos
Avidina/farmacocinética , Corantes Fluorescentes/farmacocinética , Neoplasias Ovarianas/metabolismo , Rodaminas/farmacocinética , Animais , Avidina/química , Linhagem Celular Tumoral , Detergentes/química , Feminino , Fluorescência , Corantes Fluorescentes/química , Humanos , Processamento de Imagem Assistida por Computador , Camundongos , Neoplasias Ovarianas/patologia , Rodaminas/química , Espectrometria de Fluorescência
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