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Background and purpose: Metallic hip prostheses cause substantial artefacts in both computed tomography (CT) and magnetic resonance (MR) images used in radiotherapy treatment planning (RTP) for prostate cancer patients. The aim of this study was to evaluate the dose calculation accuracy of a synthetic CT (sCT) generation workflow and the improvement in implant visibility using metal artefact reduction sequences. Materials and methods: The study included 23 patients with prostate cancer who had hip prostheses, of which 10 patients had bilateral hip implants. An in-house protocol was applied to create sCT images for dose calculation comparison. The study compared prostheses volumes and resulting avoidance sectors against planning target volume (PTV) dose uniformity and organs at risk (OAR) sparing. Results: Median PTV dose difference between sCT and CT-based dose calculation among all patients was 0.1 % (-0.4 to 0.4%) (median(range)). Bladder and rectum differences (V50Gy) were 0.2 % (-0.3 to 1.1%) and 0.1 % (-0.9 to 0.5%). The median 3D local gamma pass rate for partial arc cases using a Dixon MR sequence was Γ20%2mm/2% = 99.9%. For the bilateral full arc cases, using a metal artefact reconstruction sequence, the pass rate was Γ20%2mm/2% = 99.0%. Conclusions: An in-house protocol for generating sCT images for dose calculation provided clinically feasible dose calculation accuracy for prostate cancer patients with hip implants. PTV median dose difference for uni- and bilateral patients with avoidance sectors remained <0.4%. The Outphase images enhanced implant visibility resulting in smaller avoidance sectors, better OAR sparing, and improved PTV uniformity.
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Purpose of our research was to develop a four-dimensional (4D) magnetic resonance imaging (MRI) method of liver. Requirements of the method were to create a clinical procedure with acceptable imaging time and sufficient temporal and spatial accuracy. The method should produce useful planning image sets for stereotactic body radiation therapy delivery both during breath-hold and in free breathing. The purpose of the method was to improve the localization of liver metastasis. The method was validated with phantom tests. Imaging parameters were optimized to create a 4D dataset compressed to one respiratory cycle of the whole liver with clinically reasonable level of image contrast and artifacts. Five healthy volunteers were imaged with T2-weighted SSFSE research sequence. The respiratory surrogate signal was observed by the linear navigator interleaved with the anatomical liver images. The navigator was set on head-feet - direction on the superior surface of the liver to detect the edge of diaphragm. The navigator signal and 2D liver image data were retrospectively processed with a self-developed MATLAB algorithm. A deformable phantom for 4D imaging tests was constructed by combining deformable tissue-equivalent material and a commercial programmable motor unit of the 4D phantom with a clinically relevant range of deformation patterns. 4D Computed Tomography images were used as reference to validate the MRI protocol. The best compromise of reasonable accuracy and imaging time was found with 2D T2-weighted SSFSE imaging sequence using parameters: TR = 500-550 ms, images/slices = 20, slice thickness = 3 mm. Then, image processing with number of respiratory phases = 8 constructed accurate 4D images of liver. We have developed the 4D-MRI method visualizing liver motions three-dimensionally in one representative respiratory cycle. From phantom tests it was found that the spatial agreement to 4D-CT is within 2 mm that is considered sufficient for clinical applications.
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Tomografia Computadorizada Quadridimensional , Imageamento por Ressonância Magnética , Humanos , Imageamento Tridimensional , Fígado/diagnóstico por imagem , Imagens de Fantasmas , Respiração , Estudos RetrospectivosRESUMO
BACKGROUND: Pineal region tumors represent challenging surgical lesions with wide ranges of survival reported in different surgical series. In this article, we emphasize the role of complete microsurgical resection (CMR) to obtain a favorable long-term outcome of pineal region tumors. METHODS: We report a retrospective study of pineal region tumors operated on in Helsinki Neurosurgery between 1997 and 2015. Information was obtained from the hospital records, and an evaluation of the Finnish population register was conducted in July 2018 to determine the current status of the patients. RESULTS: A total of 76 pineal region tumors were operated on. The survival was 62% at a mean follow-up of 125 ± 105 months (range, 0-588 months), and the disease-related mortality was limited to 14 patients (18.4%). Up to July 2018, 29 patients had died. Two patients died 1 and 3 months after surgery of delayed thalamic infarctions, 12 patients of disease progression, and 15 had non-disease-related deaths. Only 1 patient was lost in the long-term follow-up. Ten of 14 disease-related deaths occurred during the first 5 years of follow-up: 5 diffuse gliomas, 3 germ cell tumors, 1 grade II-III pineal parenchymal tumor of intermediate differentiation, and 1 meningioma. CMR was linked to better tumor-free survival and long-term survival, with the exception of diffuse gliomas. CONCLUSIONS: CMR, in the setting of a multidisciplinary management of pineal region tumors, correlates with favorable survival and with minimal mortality. Surgically treated grade II-IV gliomas constitute a particular group with high mortality within the first 5 years independently of the microsurgical resection.
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Neoplasias Encefálicas/cirurgia , Glioma/cirurgia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Neoplasias Embrionárias de Células Germinativas/cirurgia , Glândula Pineal/cirurgia , Pinealoma/cirurgia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Astrocitoma/mortalidade , Astrocitoma/patologia , Astrocitoma/cirurgia , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Feminino , Finlândia , Glioma/mortalidade , Glioma/patologia , Humanos , Lactente , Masculino , Neoplasias Meníngeas/mortalidade , Neoplasias Meníngeas/patologia , Meningioma/mortalidade , Meningioma/patologia , Microcirurgia , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/mortalidade , Neoplasias Embrionárias de Células Germinativas/patologia , Procedimentos Neurocirúrgicos , Glândula Pineal/patologia , Pinealoma/mortalidade , Pinealoma/patologia , Radioterapia Adjuvante , Estudos Retrospectivos , Sobrevida , Carga Tumoral , Adulto JovemRESUMO
BACKGROUND: Pineal parenchymal tumors of intermediate differentiation (PPTIDs) are rare lesions with particular features compared with other pineal parenchymal tumors. METHODS: We present a retrospective review of patients with histologically confirmed PPTIDs who were operated on in our department between 1997 and 2015. A demographic analysis and an evaluation of preoperative status, surgical treatment, as well as immediate and long-term clinical and radiologic outcomes were conducted. RESULTS: Fifteen patients with PPTIDs were operated on between 1997 and 2015. Gross total removal was achieved in 11 cases; 2 patients underwent near-total resection, 1 partial resection, and 1 received brachytherapy after an endoscopic biopsy. Nine patients required external radiation therapy (4 due to a pleomorphic histology of their lesion including pineoblastoma features in 3 of them; 3 after a subtotal resection; and 2 for tumor recurrence). No patient received chemotherapy. The survival rate of our patients was 57.1% at a mean follow-up of 137.2 ± 77.6 months (39-248 months). CONCLUSIONS: A proper multidisciplinary management of PPTIDs based on a gross total removal of the lesion, and an adjuvant radiotherapy in selected cases, may improve the overall survival of these aggressive tumors.
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Neoplasias Encefálicas/cirurgia , Diferenciação Celular , Procedimentos Neurocirúrgicos/tendências , Glândula Pineal/cirurgia , Pinealoma/cirurgia , Adulto , Idoso , Neoplasias Encefálicas/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Glândula Pineal/diagnóstico por imagem , Pinealoma/diagnóstico por imagem , Pinealoma/mortalidade , Estudos Retrospectivos , Fatores de TempoRESUMO
BACKGROUND: Vascular pineal malformations are rare and technically demanding lesions. Because the locations of these lesions, endovascular techniques and radiosurgery have been increasingly used in the recent decades to accomplish safe occlusion. Nevertheless, microsurgical treatment may be required sometimes. METHODS: We present a retrospective review of the vascular pineal malformations operated by the senior author. Moreover, we report illustrative cases for the various types of vascular lesions with a careful analysis of the different microsurgical stages. RESULTS: Eighteen patients with pineal vascular lesions were operated on between 1980 and 2015: 6 patients had vein of Galen malformations, 5 plexiform arteriovenous malformations, 6 cavernous malformations, and 1 patient had a ruptured medial posterior choroidal artery aneurysm. A complete resection and occlusion was possible in all vascular malformations. CONCLUSIONS: The pineal region is an infrequent but challenging location for vascular lesions. A careful and stepwise operative strategy for the different types of vascular lesion is paramount to accomplish an effective and safe microsurgical treatment when other alternatives fail or are not available.
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Malformações Arteriovenosas Intracranianas/cirurgia , Microcirurgia , Glândula Pineal/irrigação sanguínea , Glândula Pineal/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Glândula Pineal/diagnóstico por imagem , Estudos RetrospectivosRESUMO
BACKGROUND: Papillary tumor of the pineal region (PTPR) is a rare grade II-III pineal lesion with peculiar histological and immunohistochemical features. These tumors mostly occur in adults, only rarely in children, with 19 cases reported up to now. CASE DESCRIPTION: We present a 3-year-old boy who underwent reoperation for a recurrent PTPR (grade II). Gross total resection of the lesion through an occipital interhemispheric approach with the patient in a sitting position was followed by adjuvant radiotherapy and chemotherapy. Histological examination revealed tumor progression (grade III) and an MIB-1 proliferation index >25%. The patient continues to do well with no evidence of recurrence more than 3 years following surgery. A comprehensive literature review regarding the PTPR, including the current management in children, is reported. CONCLUSIONS: PTPRs are extremely rare in children, and immunohistochemistry is needed to differentiate them from other pineal tumors. These tumors show a high rate of recurrence, and a multidisciplinary management approach (microsurgical resection followed by radiotherapy and/or chemotherapy) can help achieve a favorable outcome.
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Carcinoma Papilar/diagnóstico , Carcinoma Papilar/terapia , Pinealoma/diagnóstico , Pinealoma/terapia , Carcinoma Papilar/patologia , Criança , Terapia Combinada , Humanos , Masculino , Recidiva Local de Neoplasia , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/patologia , Glândula Pineal/cirurgia , Pinealoma/patologiaRESUMO
BACKGROUND: Magnetic resonance imaging (MRI) is the most comprehensive imaging modality for radiation therapy (RT) target delineation of most soft tissue tumors including prostate cancer. We have earlier presented step by step the MRI-only based workflow for RT planning and image guidance for localized prostate cancer. In this study we present early clinical experiences of MRI-only based planning. MATERIAL AND METHODS: We have analyzed the technical planning workflow of the first 200 patients having received MRI-only planned radiation therapy for localized prostate cancer in Helsinki University Hospital Cancer center. Early prostate specific antigen (PSA) results were analyzed from n = 125 MRI-only patients (n = 25 RT only, n = 100 hormone treatment + RT) and were compared with the corresponding computed tomography (CT) planned patient group. RESULTS: Technically the MRI-only planning procedure was suitable for 92% of the patients, only 8% of the patients required supplemental CT imaging. Early PSA response in the MRI-only planned group showed similar treatment results compared with the CT planned group and with an equal toxicity level. CONCLUSION: Based on this retrospective study, MRI-only planning procedure is an effective and safe way to perform RT for localized prostate cancer. It is suitable for the majority of the patients.
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Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Fluxo de Trabalho , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia Conformacional/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
OBJECTIVE: Microsurgical skills and eye-hand coordination need continuous training to be developed and refined. However, well-equipped microsurgical laboratories are not so widespread as their setup is expensive. Herein, we present a novel microsurgical training system that requires a high-resolution personal computer screen, smartphones, and virtual reality glasses. METHODS: A smartphone placed on a holder at a height of about 15-20 cm from the surgical target field is used as the webcam of the computer. A specific software is used to duplicate the video camera image. The video may be transferred from the computer to another smartphone, which may be connected to virtual reality glasses. RESULTS: Using the previously described training model, we progressively performed more and more complex microsurgical exercises. It did not take long to set up our system, thus saving time for the training sessions. CONCLUSION: Our proposed training model may represent an affordable and efficient system to improve eye-hand coordination and dexterity in using not only the operating microscope but also endoscopes and exoscopes.
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Competência Clínica , Microcirurgia/educação , Procedimentos Neurocirúrgicos/educação , Realidade Virtual , Simulação por Computador , Humanos , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Smartphone , Interface Usuário-ComputadorRESUMO
BACKGROUND AND PURPOSE: Recent studies have shown that it is possible to conduct entire radiotherapy treatment planning (RTP) workflow using only MR images. This study aims to develop a generalized intensity-based method to generate synthetic CT (sCT) images from standard T2-weighted (T2w) MR images of the pelvis. MATERIALS AND METHODS: This study developed a generalized dual model HU conversion method to convert standard T2w MR image intensity values to synthetic HU values, separately inside and outside of atlas-segmented bone volume contour. The method was developed and evaluated with 20 and 35 prostate cancer patients, respectively. MR images with scanning sequences in clinical use were acquired with four different MR scanners of three vendors. RESULTS: For the generated synthetic CT (sCT) images of the 35 prostate patients, the mean (and maximal) HU differences in soft and bony tissue volumes were 16⯱â¯6â¯HUs (34â¯HUs) and -46⯱â¯56â¯HUs (181â¯HUs), respectively, against the true CT images. The average of the PTV mean dose difference in sCTs compared to those in true CTs was -0.6⯱â¯0.4% (-1.3%). CONCLUSIONS: The study provides a generalized method for sCT creation from standard T2w images of the pelvis. The method produced clinically acceptable dose calculation results for all the included scanners and MR sequences.
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Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/radioterapia , Tomografia Computadorizada por Raios X/métodos , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Planejamento da Radioterapia Assistida por Computador/métodosRESUMO
PURPOSE: Gastrointestinal stromal tumor (GIST) has been considered radiation-resistant, and radiotherapy is recommended only for palliation of bone metastases in current treatment guidelines. No registered prospective trial has evaluated GIST responsiveness to radiotherapy. PATIENTS AND METHODS: Patients with GIST progressing at intra-abdominal sites or the liver were entered to this prospective Phase II multicenter study (identifier NCT00515931). Metastases were treated with external beam radiotherapy using either conformal 3D planning or intensity modulated radiotherapy and conventional fractionation to a cumulative planning target volume dose of approximately 40 Gy. Systemic therapy was maintained unaltered during the study. RESULTS: Of the 25 patients entered, 19 were on concomitant tyrosine kinase inhibitor therapy, most often imatinib. Two (8%) patients achieved partial remission, 20 (80%) had stable target lesion size for ⩾3 months after radiotherapy with a median duration of stabilization of 16 months, and 3 (12%) progressed. The median time to radiotherapy target lesion progression was 4-fold longer than the median time to GIST progression at any site (16 versus 4 months). Radiotherapy was generally well tolerated. CONCLUSIONS: Responses to radiotherapy were infrequent, but most patients had durable stabilization of the target lesions. GIST patients with soft tissue metastases benefit frequently from radiotherapy.
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Neoplasias Gastrointestinais/radioterapia , Tumores do Estroma Gastrointestinal/radioterapia , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/antagonistas & inibidores , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimiorradioterapia , Feminino , Neoplasias Gastrointestinais/tratamento farmacológico , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Planejamento da Radioterapia Assistida por ComputadorRESUMO
PURPOSE: To investigate the conversion of prostate cancer radiotherapy (RT) target definition from CT-based planning into an MRI-only-based planning procedure. MATERIALS AND METHODS: Using the CT- and MRI-only-based RT planning protocols, 30 prostate cancer patients were imaged in the RT fixation position. Two physicians delineated the prostate in both CT and T2-weighted MRI images. The CT and MRI images were coregistered based on gold seeds and anatomic borders of the prostate. The uncertainty of the coregistration, as well as differences in target volumes and uncertainty of contour delineation were investigated. Conversion of margins and dose constraints from CT- to MRI-only-based treatment planning was assessed. RESULTS: On average, the uncertainty of image coregistration was 0.4 ± 0.5 mm (one standard deviation, SD), 0.9 ± 0.8 mm and 0.9 ± 0.9 mm in the lateral, anterior-posterior and base-apex direction, respectively. The average ratio of the prostate volume between CT and MRI was 1.20 ± 0.15 (one SD). Compared to the CT-based contours, the MRI-based contours were on average 2-7 mm smaller in the apex, 0-1 mm smaller in the rectal direction and 1-4 mm smaller elsewhere. CONCLUSION: When converting from a CT-based planning procedure to an MRI-based one, the overall planning target volumes (PTV) are prominently reduced only in the apex. The prostate margins and dose constraints can be retained by this conversion.
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Adenocarcinoma/radioterapia , Imageamento por Ressonância Magnética/métodos , Neoplasias da Próstata/radioterapia , Radioterapia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X/métodos , Adenocarcinoma/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Neoplasias da Próstata/diagnóstico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do TratamentoRESUMO
BACKGROUND: Reduction of saliva secretion is a common side effect following radiotherapy (RT) for cancer of the head and neck region. The aim of this study is to predict the post-RT salivary function for individual patients prior to treatment and to recognise possible differences in individual radiosensitivity. MATERIAL AND METHODS: A predictive model for post-RT salivary function was validated for 64 head and neck cancer patients. The input parameters for the model were salivary excretion fraction (sEF) measured by 99mTc-pertechnetate scintigraphy, total stimulated salivary flow and mean absorbed dose for the major salivary glands. SEF values after RT relative to the baseline before RT (rEF) were compared among the patients using the distance ΔrEF between single gland rEF and the corresponding expected value at the dose response curve. RESULTS: A significant correlation (R = 0.86, p = 0.018) was found between the modelled and the measured values of stimulated salivary flow six months after RT. The average prediction error for the saliva flow rate was 6 ml/15 min. A linear relationship between ΔrEF for the left and the right parotid glands was observed both six (R = 0.53) and 12 (R = 0.79) months after RT. The average of absolute values of ΔrEF was 0.20 for parotid glands and 0.22 for submandibular glands. CONCLUSIONS: The salivary flow model was validated for 64 patients. The results imply, that one explanation for the discrepancies between the predicted and the measured salivary flow rate values and the common variations found in ΔrEF for the parotid glands may be differences in patients' individual response to radiation. However, quantitative extraction of individual radiosensitivity would require further studies in order to take it into account in predictive models.
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Neoplasias de Cabeça e Pescoço/radioterapia , Lesões por Radiação/prevenção & controle , Saliva/metabolismo , Humanos , Modelos Biológicos , Medicina de Precisão/métodos , Cintilografia , Fatores de Risco , Saliva/efeitos da radiaçãoRESUMO
BACKGROUND: Adaptive radiation therapy (ART) for urinary bladder cancer has emerged as a promising alternative to conventional RT with potential to minimize radiation-induced toxicity to healthy tissues. In this work we have studied bladder volume variations and their effect on healthy bladder dose sparing and intrafractional margins, in order to refine our ART strategy. MATERIAL AND METHODS: An online ART treatment strategy was followed for five patients with urinary bladder cancer with the tumors demarcated using Lipiodol(®). A library of 3-4 predefined treatment plans for each patient was created based on four successive computed tomography (CT) scans. Cone beam CT (CBCT) images were acquired before each treatment fraction and after the treatment at least weekly. In partial bladder treatment the sparing of the healthy part of the bladder was investigated. The bladder wall displacements due to bladder filling were determined in three orthogonal directions (CC, AP, DEX-SIN) using the treatment planning CT scans. An ellipsoidal model was applied in order to find the theoretical maximum values for the bladder wall displacements. Moreover, the actual bladder filling rate during treatment was evaluated using the CBCT images. Results. In partial bladder treatment the volume of the bladder receiving high absorbed doses was generally smaller with a full than empty bladder. The estimation of the bladder volume and the upper limit for the intrafractional movement of the bladder wall could be represented with an ellipsoidal model with a reasonable accuracy. Observed maximum growth of bladder dimensions was less than 10 mm in all three orthogonal directions during 15 minute interval. CONCLUSION: The use of Lipiodol contrast agent enables partial bladder treatment with reduced irradiation of the healthy bladder volume. The ellipsoidal bladder model can be used for the estimation of the bladder volume changes and the upper limit of the bladder wall movement during the treatment fraction.
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Tomografia Computadorizada de Feixe Cônico , Processamento de Imagem Assistida por Computador , Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Tomografia Computadorizada por Raios X , Neoplasias da Bexiga Urinária/radioterapia , Bexiga Urinária/efeitos da radiação , Fracionamento da Dose de Radiação , Humanos , Estadiamento de Neoplasias , Órgãos em Risco/efeitos da radiação , Prognóstico , Radioterapia de Intensidade Modulada , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/diagnóstico por imagemRESUMO
In radiotherapy, target tissues are defined best on MR images due to their superior soft tissue contrast. Computed tomography imaging is geometrically accurate and it is needed for dose calculation and generation of reference images for treatment localization. Co-registration errors between MR and computed tomography images can be eliminated using magnetic resonance imaging-only based treatment planning. Use of ionizing radiation can be avoided which is especially important in adaptive treatments requiring several re-scans. We commissioned magnetic resonance imaging-only based procedure for external radiotherapy, treatment planning of the prostate cancer. Geometrical issues relevant in radiotherapy, were investigated including quality assurance testing of the scanner, evaluation of the displacement of skin contour and radiosensitive rectum wall, and detection of intraprostatic fiducial gold seed markers used for treatment localization. Quantitative analysis was carried out for 30 randomly chosen patients. Systematic geometrical errors were within 2.2 mm. The gold seed markers were correctly identified for 29 out of the 30 patients. Positions of the seed midpoints were consistent within 1.3 mm in magnetic resonance imaging and computed tomography. Positional error of rectal anterior wall due to susceptibility effect was minimal. Geometrical accuracy of the investigated equipment and procedure was sufficient for magnetic resonance imaging-only based radiotherapy, treatment planning of the prostate cancer including treatment virtual simulation.
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Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/normas , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Radioterapia Conformacional/instrumentação , Radioterapia Conformacional/normas , Marcadores Fiduciais/normas , Finlândia , Humanos , Masculino , Garantia da Qualidade dos Cuidados de Saúde , Radioterapia Conformacional/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/normasRESUMO
BACKGROUND AND PURPOSE: To evaluate the patterns of locoregional relapse and survival following submandibular gland (SMG)-sparing intensity modulated radiotherapy (IMRT). PATIENTS AND METHODS: Eighty patients with laryngeal (n = 15), oropharyngeal (n = 50), hypopharyngeal (n = 11) or nasopharyngeal cancer (n = 4) were treated by submandibular gland-sparing IMRT for head and neck squamous cell cancer between July 2000 and December 2008. All patients were treated by bilateral IMRT. Thirty-nine (49%) received definitive radiotherapy (RT) and 41 (51%) postoperative RT. The contralateral parotid gland (PG) and SMG were included in the dose optimization planning program with intent to keep the mean doses for PG and SMG below 23 Gy and 28-30 Gy, respectively. The ipsilateral glands were also spared when considered feasible. RESULTS: During a median follow-up time of 51 months (range, 24-117 months) nine local recurrent tumors were observed. Four of these nine patients were salvaged by surgery with no further recurrence. All local recurrences were located within the high-dose CTVs. None of the locally recurrent cancers were located at the vicinity of the spared PGs or SMGs. No recurrent tumors were observed in the contralateral neck. The Kaplan-Meier estimate for local control at five years following IMRT was 88% for the whole cohort and the corresponding figure for local control following salvage surgery was 94%. The estimates for five-year overall survival and disease-specific survival were 85% and 90%, respectively. CONCLUSION: In selected head and neck cancer patients who are estimated to have a low risk of cancer recurrence at the nodal levels I-II and who are treated with SMG-sparing IMRT the risk of cancer recurrence at the vicinity of the spared salivary glands is low.
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Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Tratamentos com Preservação do Órgão , Lesões por Radiação/prevenção & controle , Radioterapia de Intensidade Modulada , Glândula Submandibular/efeitos da radiação , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/radioterapia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Taxa de Sobrevida , Resultado do TratamentoAssuntos
Antineoplásicos/administração & dosagem , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/terapia , Quinazolinas/administração & dosagem , Terapia Combinada/métodos , Relação Dose-Resposta a Droga , Esquema de Medicação , Gefitinibe , Humanos , Masculino , Prostatectomia , Neoplasias da Próstata/sangue , Resultado do TratamentoRESUMO
PURPOSE: To investigate the efficacy and safety of boron neutron capture therapy (BNCT) in the treatment of inoperable head-and-neck cancers that recur locally after conventional photon radiation therapy. METHODS AND MATERIALS: In this prospective, single-center Phase I/II study, 30 patients with inoperable, locally recurred head-and-neck cancer (29 carcinomas and 1 sarcoma) were treated with BNCT. Prior treatments consisted of surgery and conventionally fractionated photon irradiation to a cumulative dose of 50 to 98 Gy administered with or without concomitant chemotherapy. Tumor responses were assessed by use of the RECIST (Response Evaluation Criteria in Solid Tumors) and adverse effects by use of the National Cancer Institute common terminology criteria version 3.0. Intravenously administered L-boronophenylalanine-fructose (400 mg/kg) was administered as the boron carrier. Each patient was scheduled to be treated twice with BNCT. RESULTS: Twenty-six patients received BNCT twice; four were treated once. Of the 29 evaluable patients, 22 (76%) responded to BNCT, 6 (21%) had tumor growth stabilization for 5.1 and 20.3 months, and 1 (3%) progressed. The median progression-free survival time was 7.5 months (95% confidence interval, 5.4-9.6 months). Two-year progression-free survival and overall survival were 20% and 30%, respectively, and 27% of the patients survived for 2 years without locoregional recurrence. The most common acute Grade 3 adverse effects were mucositis (54% of patients), oral pain (54%), and fatigue (32%). Three patients were diagnosed with osteoradionecrosis (each Grade 3) and one patient with soft-tissue necrosis (Grade 4). Late Grade 3 xerostomia was present in 3 of the 15 evaluable patients (20%). CONCLUSIONS: Most patients who have inoperable, locally advanced head-and-neck carcinoma that has recurred at a previously irradiated site respond to boronophenylalanine-mediated BNCT, but cancer recurrence after BNCT remains frequent. Toxicity was acceptable. Further research on novel modifications of the method is warranted.
Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Carcinoma Adenoide Cístico/radioterapia , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Sarcoma/radioterapia , Adulto , Idoso , Compostos de Boro/uso terapêutico , Terapia por Captura de Nêutron de Boro/efeitos adversos , Carcinoma Adenoide Cístico/mortalidade , Carcinoma de Células Escamosas/mortalidade , Intervalos de Confiança , Intervalo Livre de Doença , Fadiga/etiologia , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/etiologia , Mucosite/etiologia , Recidiva Local de Neoplasia/mortalidade , Osteorradionecrose/etiologia , Dor/etiologia , Fenilalanina/análogos & derivados , Fenilalanina/uso terapêutico , Estudos Prospectivos , Dosagem Radioterapêutica , Xerostomia/etiologiaRESUMO
BACKGROUND AND PURPOSE: To evaluate the benefits of adaptive radiotherapy for bladder cancer in decreasing irradiation of small bowel. MATERIAL AND METHODS: Five patients with muscle invasive bladder cancer received adaptive radiotherapy to a total dose of 55.8-65 Gy with daily cone-beam computed tomography scanning. The whole bladder was treated to 45-50.4 Gy, followed by a partial bladder boost. The plan of the day was chosen from 3 to 4 pre-planned treatment plans according to the visible extent of bladder wall in cone-beam computed tomography images. Dose volume histograms for intestinal cavity volumes were constructed and compared with corresponding histograms calculated for conventional non-adaptive radiotherapy with single treatment plan of 2 cm CTV-PTV margins. CTV dose coverage in adaptive treatment technique was compared with CTV dose coverage in conventional radiotherapy. RESULTS: The average volume of intestinal cavity receiving ≥ 45 Gy was reduced from 335 ± 106 cm(3) to 180 ± 113 cm(3) (1SD). The maximum volume of intestinal cavity spared at 45 Gy on a single patient was 240 cm(3), while the minimum volume was 65 cm(3). The corresponding reduction in average intestinal cavity volume receiving ≥ 45 Gy calculated for the whole bladder treatment only was 66 ± 36 cm(3). CTV dose coverage was improved on two out of five patients and decreased on three patients. CONCLUSIONS: Adaptive radiotherapy considerably reduces dose to the small bowel, while maintaining the dose coverage of CTV at similar level when compared to the conventional treatment technique.
Assuntos
Intestino Delgado/efeitos da radiação , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias da Bexiga Urinária/radioterapia , Idoso , Comorbidade , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Masculino , Invasividade Neoplásica , Estadiamento de Neoplasias , Radiografia Intervencionista , Dosagem Radioterapêutica , Resultado do Tratamento , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Neoplasias da Bexiga Urinária/patologiaRESUMO
BACKGROUND: To investigate the patterns of relapse following intensity modulated radiotherapy (IMRT) given after radical surgery for oral and oropharyngeal squamous cell cancer. PATIENTS AND METHODS: One hundred and two patients with oral or oropharyngeal cancer were treated with radical surgery followed by IMRT up to a mean total dose of 60 Gy between years 2001 and 2007. Thirty-nine of the patients (%) also received concomitant weekly cisplatin. Forty of the patients had oral and 62 had oropharyngeal cancer. Data on the tumour, patient and treatment factors were collected. Following therapy the patients were followed by clinical examination, endoscopy and MRI/CT at 2- to 3-months interval up to 2 years and thereafter at 6-month intervals. RESULTS: The mean follow-up time of the patients was 55 months (range, 26-106 months). The rate for local tumour control for the whole cohort was 92.2%: 87.5% for oral cancer patients and 96.7% for oropharyngeal cancer patients. The 5-year disease specific survival was 90.2% and 5-year overall survival 84.3%. During the follow-up eight locoregional recurrences were observed, three at the primary tumour site and one at regional nodal site and four at both sites. The mean time to primary tumour recurrence was seven months (range, 2-10 months) and to nodal recurrence seven months (range, 2-12 months). Distant metastasis occurred in six (6%) patients. The factors associated with poor prognosis were the primary tumour size and tumour site with oral cancers having worse outcome. The treatment was well tolerated with no unexpected toxicities. The most frequent late toxicity was dysphagia necessitating permanent PEG in five patients. This was correlated with the advanced primary tumour size and resulting in wide tumour excision and reconstruction. CONCLUSIONS: Surgery combined with postoperative radiotherapy given as IMRT results in low level of tumour recurrence.
Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Neoplasias Orofaríngeas , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Cisplatino/uso terapêutico , Estudos de Coortes , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Recidiva Local de Neoplasia , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/radioterapia , Neoplasias Orofaríngeas/cirurgia , Radiografia , Radioterapia de Intensidade Modulada , Recidiva , Fatores de TempoRESUMO
PURPOSE: To investigate the safety of boronophenylalanine-mediated boron neutron capture therapy (BNCT) in the treatment of malignant gliomas that progress after surgery and conventional external beam radiation therapy. METHODS AND MATERIALS: Adult patients who had histologically confirmed malignant glioma that had progressed after surgery and external beam radiotherapy were eligible for this Phase I study, provided that >6 months had elapsed from the last date of radiation therapy. The first 10 patients received a fixed dose, 290 mg/kg, of L-boronophenylalanine-fructose (L-BPA-F) as a 2-hour infusion before neutron irradiation, and the remaining patients were treated with escalating doses of L-BPA-F, either 350 mg/kg, 400 mg/kg, or 450 mg/kg, using 3 patients on each dose level. Adverse effects were assessed using National Cancer Institute Common Toxicity Criteria version 2.0. RESULTS: Twenty-two patients entered the study. Twenty subjects had glioblastoma, and 2 patients had anaplastic astrocytoma, and the median cumulative dose of prior external beam radiotherapy was 59.4 Gy. The maximally tolerated L-BPA-F dose was reached at the 450 mg/kg level, where 4 of 6 patients treated had a grade 3 adverse event. Patients who were given >290 mg/kg of L-BPA-F received a higher estimated average planning target volume dose than those who received 290 mg/kg (median, 36 vs. 31 Gy [W, i.e., a weighted dose]; p = 0.018). The median survival time following BNCT was 7 months. CONCLUSIONS: BNCT administered with an l-BPA-F dose of up to 400 mg/kg as a 2-hour infusion is feasible in the treatment of malignant gliomas that recur after conventional radiation therapy.