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1.
BMC Oral Health ; 24(1): 630, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811865

RESUMEN

INTRODUCTION: This longitudinal study assessed the association between salivary protein composition and the clinical onset/severity of oral mucositis (OM) in patients with head and neck tumours treated with intensity-modulated-radiotherapy (IMRT). METHODS: Saliva samples/clinical data were obtained from 40 head and neck cancer patients treated at Guy's Hospital before -IMRT(T0) and after-IMRT (T1 = 6 m, T2 = 12 m) (ethics approval/consent). Salivary flow rate, total protein concentration, and secretion rate were determined from saliva samples and compared with pre-treatment values. OM was assessed, total/specific salivary proteins, including mucin 5B and 7, IgA, cystatin-S, albumin, and α-amylase, were quantified. RESULTS: 95% patients experienced OM during IMRT, with 33 subjects reaching grade 2&3. At T1, there was a significant reduction in salivary flow rate, total protein secretion rate, α-amylase and cystatin-S compared to baseline. Remarkably IMRT did not significantly alter mucin 5B and 7, or the IgA secretion rate at any time point. At T1, all the analyzed proteins were associated with the OM outcomes. In addition, there was a significant inverse correlation between IgA concentration at T0 and the severity of OM during IMRT. CONCLUSION: This study revealed significant associations between several salivary proteins and OM in patients with head and neck cancer undergoing IMRT. Further longitudinal studies are needed to confirm these results. CLINICAL SIGNIFICANCE: The study contributes to the understanding of certain salivary proteins association with OM. This could be the first step towards identifying potential salivary markers that could offer perspectives for personalized medicine approaches to improve their quality of life (QoL). RESEARCH QUESTION: What is the association between salivary proteins and the occurrence and severity of OM in head and neck cancer patients? AIM: To assess the association between salivary protein composition with the clinical onset/severity of oral mucositis (OM) in head and neck cancer patients treated with intensity modulated radiotherapy. NULL HYPOTHESIS: There is no association between salivary proteins and onset/severity of OM in HNC patients.


Asunto(s)
Neoplasias de Cabeza y Cuello , Radioterapia de Intensidad Modulada , Proteínas y Péptidos Salivales , Estomatitis , Humanos , Estudios Longitudinales , Neoplasias de Cabeza y Cuello/radioterapia , Estomatitis/etiología , Estomatitis/metabolismo , Masculino , Proteínas y Péptidos Salivales/análisis , Femenino , Persona de Mediana Edad , Radioterapia de Intensidad Modulada/efectos adversos , Anciano , Saliva/metabolismo , Adulto , alfa-Amilasas/análisis , alfa-Amilasas/metabolismo
2.
BMC Health Serv Res ; 24(1): 417, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38570764

RESUMEN

BACKGROUND: Adjuvant radiotherapy represents a key component in curative-intent treatment for early-stage breast cancer patients. In recent years, two accelerated partial breast irradiation (APBI) techniques are preferred for this population in our organization: electron-based Intraoperative radiation therapy (IORT) and Linac-based External Beam Radiotherapy, particularly Intensity-modulated radiation therapy (IMRT). Recently published long-term follow-up data evaluating these technologies have motivated a health technology reassessment of IORT compared to IMRT. METHODS: We developed a Markov model to simulate health-state transitions from a cohort of women with early-stage breast cancer, after lumpectomy and adjuvant APBI using either IORT or IMRT techniques. The cost-effectiveness from a private health provider perspective was assessed from a disinvestment point of view, using life-years (LYs) and recurrence-free life-years (RFLYs) as measure of benefits, along with their respective quality adjustments. Expected costs and benefits, and the incremental cost-effectiveness ratio (ICER) were reported. Finally, a sensitivity and scenario analyses were performed to evaluate the cost-effectiveness using lower IORT local recurrence and metastasis rates in IORT patients, and if equipment maintenance costs are removed. RESULTS: IORT technology was dominated by IMRT in all cases (i.e., fewer benefits with greater costs). Despite small differences were found regarding benefits, especially for LYs, costs were considerably higher for IORT. For sensitivity analyses with lower recurrence and metastasis rates for IORT, and scenario analyses without equipment maintenance costs, IORT was still dominated by IMRT. CONCLUSIONS: For this cohort of patients, IMRT was, at least, non-inferior to IORT in terms of expected benefits, with considerably lower costs. As a result, IORT disinvestment should be considered, favoring the use of IMRT in these patients.


Asunto(s)
Neoplasias de la Mama , Radioterapia de Intensidad Modulada , Humanos , Femenino , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Análisis Costo-Beneficio , Cuidados Intraoperatorios/métodos , Radioterapia Adyuvante , Mastectomía Segmentaria/métodos
3.
Biomed Phys Eng Express ; 10(3)2024 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-38417163

RESUMEN

Radiometric surveys in radiotherapy bunkers have been carried out in Brazil for many years, both by the same radiotherapy facility for verification of shielding as by the regulatory agency for licensing and control purposes. In recent years, the Intensity Modulated Radiation Therapy (IMRT) technique has been gradually incorporated into many facilities. Therefore, it has been necessary to consider the increased leakage component that has an important impact on the secondary walls. For that, a radiometric survey method has been used that considers an increased 'time of beam-on' for the secondary walls. In this work we discuss two methods of doing this: the first considers that this 'time of beam-on' affects the sum of the two components, leakage and scattered. In another method it is considered that only the leakage component is affected by this extended 'time of beam-on'. We compare the methods and show that for secondary walls withU= 1 the first method overestimates dose rates by important percentages and for secondary walls withU< 1 it can both overestimate or underestimate the dose rates, depending on the parameters of the project. An optimized procedure is proposed, according to the use factor (U) of the secondary wall to be measured.


Asunto(s)
Protección Radiológica , Radioterapia de Intensidad Modulada , Protección Radiológica/métodos , Radiometría/métodos , Radioterapia de Intensidad Modulada/métodos , Planificación de la Radioterapia Asistida por Computador/métodos
4.
Clin Transl Oncol ; 26(3): 739-746, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37568008

RESUMEN

PURPOSE: To evaluate the efficacy and safety of capecitabine/cisplatin (XP) combined with intensity-modulated radiation therapy (IMRT) in patients with non-metastatic anal squamous cell carcinoma (ASCC). METHOD AND MATERIALS: All patients with ASCC who received radical concurrent chemoradiotherapy in the past 8 years were screened. Patients who received XP or mitomycin/5-fluorouracil (MF) were selected and analyzed retrospectively. RESULTS: ASCC is an uncommon cancer, there were 36 patients were included in our study. The XP group and MF group included 18 patients each. The clinical complete response (cCR) rates in the XP group and the MF group were 94.4% and 88.9%, respectively (P = 1). The 2-year local control (LC), disease-free survival (DFS), and colostomy-free survival (CFS) rates were higher in the XP group than in the MF group (100% vs 93.3%, P = 0.32). Hematologic toxicities, especially grade ≥ 3 leukopenia (11.1% vs 44.4%, P = 0.06) and neutropenia (5.6% vs 61.1%, P = 0.001), were lower in the XP group than MF group. As a result of fewer side effects, fewer patients in the XP group demanded the dose reduction of chemotherapy (11.1% vs 50%, P = 0.03) and radiation interruption (55.6% vs 77.8%, P = 0.289). Delayed radiotherapy was shorter in the XP group (2.5 vs 6.5 days, P = 0.042) than in the MF group. CONCLUSION: The XP regimen was as effective as the MF regimen in non-metastatic ASCC. Compared with the standard MF regimen, XP combined with IMRT showed higher treatment completion and lower toxicities. It could be considered a feasible alternative for patients with non-metastatic ASCC.


Asunto(s)
Neoplasias del Ano , Carcinoma de Células Escamosas , Radioterapia de Intensidad Modulada , Humanos , Capecitabina/uso terapéutico , Radioterapia de Intensidad Modulada/efectos adversos , Radioterapia de Intensidad Modulada/métodos , Cisplatino , Fluorouracilo/uso terapéutico , Estudios Retrospectivos , Mitomicina/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/efectos adversos , Quimioradioterapia/métodos , Neoplasias del Ano/tratamiento farmacológico
5.
Appl Radiat Isot ; 200: 110978, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37603966

RESUMEN

This work aims to model and characterize the radiation beam of one Accuray tomotherapy equipment using the Monte Carlo Code MCNP5 (Monte Carlo N-Particle). This tomotherapy equipment is used for delivering high doses of radiation in tumor regions to kill cancer cells and shrink the tumor during radiation therapy of cancer patients, however, the radiation can damage surrounding areas and nearby organs at risk (OAR) if the radiation field is not well delimited. In particular, intensity-modulated radiotherapy treatments (IMRT) with tomotherapy equipment offer great benefits to patients allowing treatment of tumor regions without affecting surrounding areas and OAR. Nowadays, it is well known that a correct simulation of transport of radiation in tomotherapy equipment facilitates considerably the estimation of ideal doses in the tumor, surrounding regions, and OAR. For that reason, in this work, we simulated the geometry of the 6 MV ACCURAY Tomotherapy equipment of the CECAN using the MCNP5. The model includes a TomoLINAC consisting of an electron source that emits Gaussian distribution particles with an average energy of 5.7 MeV and width of 0.3 MeV. The emitted particles impact the tungsten target and pass through primary collimators and jaws that define the irradiation field in the isocenter. To validate the geometry and radiation transport in the TomoLINAC the curves of depth dose percentage (PDD) estimated by simulation and the curves measured experimentally were tuned. In the same way, the simulated transverse and longitudinal profiles were compared with the experimental results. In addition, a comparison between the qualities of the radiation beam characterized with MCNP and measured experimentally in CECAN showed a deviation of 1%. For the simulations, cylindrical detectors located inside a water phantom were considered and it was employed the tally *F8. A good agreement was observed between the PDD's curves obtained from the simulation and those measured experimentally for a field of 5 × 10 cm2 in the isocenter and SSD (distance from the source to the surface) of 85 cm. Also, the comparison between the simulated and experimental transverse profiles obtained at 1.5 cm, 10 cm and 15 cm depth with a radiation field of 5 × 40 cm2 showed very good agreement. The longitudinal profiles were estimated with the same depths as the transverse ones, but for each of them, the openings of the jaws were 5.0 cm, 2.5 cm and 1.0 cm in the longitudinal direction, which corresponds to the direction in which the patient's table moves. The comparison between the simulated and experimental longitudinal profiles showed good concordance too. Once the radiation beam of the ACCURAY tomotherapy equipment had been characterized, experimental dose measurements were made using a Cheese phantom and two A1SL ionization chambers. These results obtained experimentally were compared with those estimated with MCNP for a field of 5 × 40 cm2 at the isocenter and SAD of 85 cm and, it was concluded that both results were similar considering the regions of uncertainty. Finally, we must highlight that the modeling and characterization of the radiation beam of CECAN's ACCURAY tomotherapy equipment can be a key tool for dose estimations in different cancer treatment plans and future research.

6.
Rep Pract Oncol Radiother ; 27(4): 684-690, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36196421

RESUMEN

Background: Benign diseases include tumours or localized growths with low potential for progression. The use of radiotherapy (RT) at a low dose (LD) or intermediate dose for benign pathologies has been widely proposed and studied. Currently, the use of RT is limited mainly to hyperproliferative and inflammatory diseases as a first or second line of treatment. Materials and methods: This was a retrospective, observational and descriptive study conducted in the Radiotherapy Unit of the Oncology Service of the General Hospital of Mexico "Dr. Eduardo Liceaga" from January 2, 2016, to December 31, 2020. Patients diagnosed with benign pathology and treated with RT were included. The response to treatment was recorded based on the imaging study report and/or clinical review that determined control of the disease, and toxicity was recorded based on the RTOG evaluation for acute effects and CTCAE V. 4.0 for chronic effects. Results: The records of 222 patients were analysed. The mean follow-up duration was 31.53 months (range 6-61), and the median was 24 months. Of all of the analysed pathologies that were treated with RT, keloid scars predominated in 112 patients (50.5%), and paragangliomas predominated in 72 patients (32.4%); the other patients were treated for rare pathologies. The prescribed dose was dependent on the diagnosis, with the mean dose being 31.63 Gy (1500-6000 cGy) and the median being 2000 cGy. Most of the cases of acute and chronic toxicity were grades 1 and 2, and a disease response was achieved in 94.1% of the patients. Conclusion: Our series shows that for cases of benign pathology, RT offers acceptable toxicity, improves quality of life and yields a good response, achieving disease control. These results suggest the inclusion of inflammatory pathology among the indications for treatment.

7.
Gels ; 8(9)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36135294

RESUMEN

Craniospinal irradiation (CSI) is a complex radiation technique employed to treat patients with primitive neuroectodermal tumors such as medulloblastoma or germinative brain tumors with the risk of leptomeningeal spread. In adults, this technique poses a technically challenging planning process because of the complex shape and length of the target volume. Thus, it requires multiple fields and different isocenters to guarantee the primary-tumor dose delivery. Recently, some authors have proposed the use IMRT technique for this planning with the possibility of overlapping adjacent fields. The high-dose delivery complexity demands three-dimensional dosimetry (3DD) to verify this irradiation procedure and motivated this study. We used an optical CT and a radiochromic Fricke-xylenol-orange gel with the addition of formaldehyde (FXO-f) to evaluate the doses delivered at the field junction region of this treatment. We found 96.91% as the mean passing rate using the gamma analysis with 3%/2 mm criteria at the junction region. However, the concentration of fail points in a determined region called attention to this evaluation, indicating the advantages of employing a 3DD technique in complex dose-distribution verifications.

8.
J Neurooncol ; 158(1): 23-31, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35451720

RESUMEN

PURPOSE: To report preliminary outcomes of high dose image-guided intensity modulated radiotherapy (IG-IMRT) in the treatment of chordomas of the sacrum, mobile spine and skull base. METHODS: Retrospective analysis of chordoma patients treated with surgery and/or radiotherapy (RT) in a single tertiary cancer center. Initial treatment was categorized as (A) Adjuvant or definitive high-dose RT (78 Gy/39fx or 24 Gy/1fx) vs (B) surgery-only or low dose RT. The primary endpoint was the cumulative incidence of local failure. RESULTS: A total of 31 patients were treated from 2010 through 2020. Median age was 55 years, tumor location was 64% sacrum, 13% lumbar, 16% cervical and 6% clivus. Median tumor volume was 148 cc (8.3 cm in largest diameter), 42% of patients received curative-intent surgery and 65% received primary RT (adjuvant or definitive). 5-year cumulative incidence of local failure was 48% in group A vs 83% in group B (p = 0.041). Tumor size > 330 cc was associated with local failure (SHR 2.2, 95% CI 1.12 to 7.45; p = 0.028). Eight patients developed distant metastases, with a median metastases-free survival of 56.1 months. 5-year survival for patients that received high dose RT was 72% vs 76% in patients that received no or low dose RT (p = 0.63). CONCLUSION: Our study suggests high-dose photon IG-IMRT improves local control in the initial management of chordomas. Health systems should promote reference centers with clinical expertise and technical capabilities to improve outcomes for this complex disease.


Asunto(s)
Cordoma , Radioterapia de Intensidad Modulada , Cordoma/diagnóstico por imagen , Cordoma/patología , Cordoma/radioterapia , Humanos , Persona de Mediana Edad , Radioterapia de Intensidad Modulada/efectos adversos , Estudios Retrospectivos , Sacro/patología , Base del Cráneo , Resultado del Tratamiento
9.
Med Biol Eng Comput ; 58(9): 2025-2037, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32623643

RESUMEN

Algorithms are an essential part of radiation therapy planning, which includes three optimizations problems: beam angle configuration, fluence map, and realization. This study addresses the third one, also called the leaf sequencing problem, which arises for each chosen irradiation angle, given the optimized fluence map. It consists in defining a sequence of configurations of a device (called multileaf collimator) that correctly delivers radiation to the patient. A usual model for this problem is the decomposition of a matrix into a weighted sum of (0,1)-matrices, called segments, in which the ones in each row appear consecutively. Each (0,1)-matrix corresponds to a configuration of the device. The realization problem has three objectives. The first one is to minimize the sum of weights assigned to the (0,1)-matrices. The second is to minimize the number of segments. Finally, the third one is to find the best order to apply those configurations. This study presents a greedy and randomized algorithm to this problem and compares it with other algorithms presented previously in the literature. Statistical tests show that our algorithm outperformed the previous ones regarding the quality indicators investigated. Graphical Abstract a Illustrates how the IMRT realization is modelled to a mathematical problem. b Shows a decomposition example of the IMRT realization. c The scheme of the algorithm that is proposed on this work, called GRA-SRA.


Asunto(s)
Algoritmos , Planificación de la Radioterapia Asistida por Computador/estadística & datos numéricos , Radioterapia de Intensidad Modulada/estadística & datos numéricos , Biología Computacional , Humanos , Aceleradores de Partículas , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/instrumentación
10.
Rep Pract Oncol Radiother ; 25(4): 586-593, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32508534

RESUMEN

AIM: Our goal was to compare conformal 3D (C3D) radiotherapy (RT), modulated intensity RT (IMRT), and volumetric modulated arc therapy (VMAT) planning techniques in treating pituitary adenomas. BACKGROUND: RT is important for managing pituitary adenomas. Treatment planning advances allow for higher radiation dosing with less risk of affecting organs at risk (OAR). MATERIALS AND METHODS: We conducted a 5-year retrospective review of patients with pituitary adenoma treated with external beam radiation therapy (C3D with flattening filter, flattening filter-free [FFF], IMRT, and VMAT). We compared dose-volume histogram data. For OARs, we recorded D2%, maximum, and mean doses. For planning target volume (PTV), we registered V95%, V107%, D95%, D98%, D50%, D2%, minimum dose, conformity index (CI), and homogeneity index (HI). RESULTS: Fifty-eight patients with pituitary adenoma were included. Target-volume coverage was acceptable for all techniques. The HI values were 0.06, IMRT; 0.07, VMAT; 0.08, C3D; and 0.09, C3D FFF (p < 0.0001). VMAT and IMRT provided the best target volume conformity (CI, 0.64 and 0.74, respectively; p < 0.0001). VMAT yielded the lowest doses to the optic pathway, lens, and cochlea. The position of the neck in extreme flexion showed that it helps in planning mainly with VMAT by allowing only one arc to be used and achieving the desired conformity, decreasing the treatment time, while allowing greater protection to the organs of risk using C3D, C3DFFF. CONCLUSIONS: Our results confirmed that EBRT in pituitary adenomas using IMRT, VMAT, C3D, C3FFF provide adequate coverage to the target. VMAT with a single arc or incomplete arc had a better compliance with desired dosimetric goals, such as target coverage and normal structures dose constraints, as well as shorter treatment time. Neck extreme flexion may have benefits in treatment planning for better preservation of organs at risk. C3D with extreme neck flexion is an appropriate treatment option when other treatment techniques are not available.

11.
Rep Pract Oncol Radiother ; 25(4): 548-555, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32494227

RESUMEN

AIM: Describe characteristics and outcomes of three patients treated with pelvic radiation therapy after kidney transplant. BACKGROUND: The incidence of pelvic cancers in kidney transplant (KT) recipients is rising. Currently it is the leading cause of death. Moreover, treatment is challenging because anatomical variants, comorbidities, and associated treatments, which raises the concern of using radiotherapy (RT). RT has been discouraged due to the increased risk of urethral/ureteral stricture and KT dysfunction. MATERIALS AND METHODS: We reviewed the electronic health records and digital planning system of patients treated with pelvic RT between December 2013 and December 2018 to identify patients with previous KT. CASES DESCRIPTION: We describe three successful cases of KT patients in which modern techniques allowed full standard RT for pelvic malignances (2 prostate and 1 vaginal cancer) with or without elective pelvic nodal RT, without allograft toxicity at short and long follow-up (up to 60 months). CONCLUSION: When needed, RT modern techniques remain a valid option with excellent oncologic results and acceptable toxicity. Physicians should give special considerations to accomplish all OAR dose constraints in the patient's specific setting. Recent publications recommend KT mean dose <4 Gy, but graft proximity to CTV makes this unfeasible. We present 2 cases where dose constraint was not achieved, and to a short follow-up of 20 months renal toxicity has not been documented. We recommend the lowest possible mean dose to the KT, but never compromising the CTV coverage, since morbimortality from recurrent or progressive cancer disease outweighs the risk of graft injury.

12.
Rep Pract Oncol Radiother ; 25(4): 568-573, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32494230

RESUMEN

AIM: The purpose of this study was to review genitourinary (GU) and gastrointestinal (GI) toxicity associated with high-dose radiotherapy (RT) delivered with 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) or volumetric arc therapy (VMAT) following radical prostatectomy (RP). BACKGROUND: RP is a therapeutic option for the management of prostate cancer (PrCa). When assessing postoperative RT techniques for PrCa, the published literature focuses on patients treated with 2-dimensional conventional methods without reflecting the implementation of 3D-CRT, IMRT, or VMAT. MATERIALS AND METHODS: A total of 83 patients were included in this analysis; 30 patients received 3D-CRT, and 53 patients received IMRT/VMAT. Acute and late symptoms of the GU and lower GI tract were retrospectively graded according to the Radiation Therapy Oncology Group and the European Organization for Research and Treatment of Cancer radiation toxicity grading systems. The relapse failure-free rate and overall survival were also evaluated. RESULTS: The rate of acute GU toxicity was 9.4% vs. 13.3% for the IMRT/VMAT and 3D-CRT groups (p = 0.583). The 5-year actuarial rates of late GI toxicity for IMRT/VMAT and 3D-CRT treatments were 1.9% and 6.7%, respectively. The rate of late GU toxicity for the IMRT/VMAT and 3D-CRT treatment groups was 7.5% and 16.6%, respectively (p = 0.199). We found no association between acute or late toxicity and the RT technique in univariate and multivariate analyses. CONCLUSION: Postprostatectomy IMRT/VMAT and 3D-CRT achieved similar morbidity and cancer control outcomes. The clinical benefit of highly conformal techniques in this setting is unclear although formal analysis is needed.

13.
Rep Pract Oncol Radiother ; 23(6): 517-527, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30534015

RESUMEN

The contribution of Image-guided Radiotherapy (IGRT) to modern radiotherapy is undeniable, being the way to bring into daily practice the dosimetric benefits of Intensity-Modulated Radiotherapy (IMRT). Organ and target motion is constant and unpredictable at the pelvis, thus posing a challenge to the safe execution of IMRT. There are potential benefits of IMRT in the radical treatment of cervical cancer patients, both in terms of dose escalation and decrease of toxicity. But it is essential to find IGRT solutions to control the aspects that can lead to geographic miss targeting or organs at risk (OAR) overdose. This review seeks to describe the problems and possible solutions in the clinical implementation of IMRT/IGRT protocols to treat intact cervical cancer patients.

14.
Clin Transl Oncol ; 20(2): 160-168, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28612199

RESUMEN

PURPOSE: To report a single-institutional experience with the use of magnetic resonance imaging (MRI)-guided radiotherapy for cancers of the head and neck. MATERIALS AND METHODS: Between October 2014 and October 2016, 18 patients with newly diagnosed cancers of the head and neck were prospectively enrolled on an institutional registry trial investigating the feasibility and efficacy of external-beam radiotherapy delivered using on-board MRI. All patients had biopsy-proven evidence of malignancy, measurable disease, and the ability to provide consent. None had previously received any treatment. Median dose was 70 Gy (range 54-70 Gy). MRI scans were obtained as part of an image-guided registration protocol for alignment prior to and during each treatment. Concurrent chemotherapy was administered to 14 patients (78%). Patient-reported outcomes were assessed using the University of Washington quality of life instrument. RESULTS: Seventeen of 18 patients completed the planned intensity-modulated radiotherapy (IMRT) treatment of which 15 (83%) had a complete response and 2 (11%) had a partial response based on initial post-therapy positron emission tomography (PET) at 3 months. The 1-year estimates of progression-free survival, overall survival, and local-regional control were 95, 96, and 95%, respectively. There were no treatment-related fatalities. The incidence of grade 3+ acute toxicity was 44%. The proportion of patients rating their health-related quality of life as "very good" or "outstanding" at 6 months and 1 year after completion of radiation therapy was 60 and 70%, respectively. CONCLUSIONS: MRI-guided radiotherapy achieves clinical outcomes comparable to contemporary series reporting on IMRT for head and neck cancer.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Imagen por Resonancia Magnética/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/patología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/métodos , Tasa de Supervivencia , Adulto Joven
15.
Oncol. clín ; 23(1): 9-14, 2018. graf, tab
Artículo en Español | LILACS | ID: biblio-909794

RESUMEN

El objetivo de este trabajo fue comparar ventajas potenciales de la radioterapia de intensidad modulada (IMRT) vs. la radioterapia 3D (3DRT) en el control loco-regional y la toxicidad aguda en pacientes con cáncer de recto localmente avanzado (CRLA). Se analizaron retrospectivamente 235 pacientes con adenocarcinoma de recto T2/T4 y N0/N1 sometidos a radioquimioterapia neoadyuvante entre febrero de 2010 y agosto de 2015. La modalidad radiante se correlacionó con los resultados clínicos (control local y a distancia) y las tasas de toxicidades agudas urinarias, hematológicas, gastrointestinales (GI) y dérmicas. Ciento cuarenta (59.6%) recibieron IMRT y 95 (40.4%) 3DRT. La mediana de seguimiento fue de 36 meses. Las tasas de recidiva local y metástasis a distancia fueron similares entre IMRT y 3DRT. No se encontraron diferencias estadísticamente significativas en control local (CL) ni en supervivencia global (SG) entre IMRT y 3DRT (p=0.56 y p=0.24, respectivamente), ni en colostomía libre para tumores rectales bajos (p=0.44). IMRT implicó menor toxicidad cutánea (p<0.001), hematológica (p<0.0001), urinaria (p=0.0017), y gastrointestinal (p=0.0006). La incidencia de diarrea grado ≥ 3 fue del 16% entre los pacientes del grupo 3DRT frente al 5% de del grupo IMRT. En el análisis univariado, el estadio clínico T, edad, KPS, y quimioterapia adyuvante se asociaron con mejor SG (todos p<0.05) y la dosis total de radiación se asoció con mejor período libre de enfermedad (p=0.0065) Postulamos que IMRT permitiría un aumento de dosis en forma segura con el potencial de aumentar la tasa de respuestas patológicas completas (RPC), en particular en tumores rectales bajos (AU)


The aim was to compare the advantages of IMRT vs. 3D in loco regional control and acute toxicity in patients with locally advanced rectum cancer. We analyzed retrospectively 235 patients with rectal adenocarcinoma T2/T4 and N0/N1 undergoing chemo radiation between February 2010 and August 2015. The radiant modality was correlated with clinical outcomes (local and systemic control) and rates of acute urinary, hematological, gastrointestinal and dermal toxicities. One hundred and forty patients (59.6%) received IMRT and 95 (40.4%) received 3D. The median follow-up time was 36 months. The rates of local recurrence and distant metastases were similar between IMRT vs. 3D. No statistically significant differences were found in local control or survival between IMRT and 3D (p=0.56 and p =0.24, respectively), nor in free colostomy for low rectal tumors (p= 0.44). IMRT resulted in lower dermal (p<0.001), hematological (p<0.0001), urinary (p=0.0017), and gastrointestinal toxicity (p=0.0006). The incidence of diarrhea grade ≥ 3 was 16% among 3D patients vs. 5% in IMRT. In the univariate analysis, clinical stage T, age, KPS, and adjuvant chemotherapy were associated with better overall survival (all p<0.05) and the total dose of radiation was associated with better disease-free period (p=0.0065). We postulate that IMRT would allow us to increase dose in a safe manner with the potential to increase rate of complete pathological responses, particularly in low rectal tumors (AU)


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Neoplasias del Recto/radioterapia , Terapia Neoadyuvante
16.
Oncol. clín ; 23(1): 15-21, 2018. tab, graf
Artículo en Español | LILACS | ID: biblio-909898

RESUMEN

Las técnicas definitivas de quimio-radioterapia para el cáncer anal, radioterapia tridimensional conformada (3DCRT) o radioterapia de intensidad modulada (IMRT) dan excelentes resultados a largo plazo. Evaluamos resultados en centros de radiación basados en la comunidad. Se evaluaron retrospectivamente 281 pacientes tratados con quimio-radioterapia definitiva para carcinoma anal loco-regional, entre 2006 y 2014. El 95% realizó quimioterapia. Se evaluaron datos de toxicidades, progresión de la enfermedad y necesidad de colostomía durante el período de seguimiento. La supervivencia global, supervivencia libre de progresión y colostomía libre se calcularon con métodos de Kaplan-Meier. La edad media fue 63.7 años con seguimiento medio de 60 meses. Ciento sesenta y nueve pacientes recibieron IMRT y 112 recibieron 3DCRT. La dosis total media tumoral fue 54 Gy. El 80% experimentó complicaciones agudas, y el 56% requirió interrupción de tratamiento. No hubo diferencias significativas en supervivencia global, supervivencia libre de progresión, supervivencia libre de colostomía ni control local a dos años entre ambos grupos. La IMRT tuvo menos suspensión del tratamiento (48% vs. 65%) (p=0.0261). El grupo IMRT tuvo una reducción significativa de todas las toxicidades agudas ≥3 y gastrointestinales (GI) tardías, en comparación con los tratados con 3DCRT. Esta serie representa una de las mayores comparaciones 3DCRT vs. IMRT para el tratamiento definitivo de cáncer anal. Los resultados a largo plazo no difieren significativamente en función de la técnica de radioterapia (RT). La IMRT reduce todas las toxicidades ≥ grado 3 y la necesidad de interrupción en comparación con 3DCRT (AU)


The definitive techniques of chemo-radiotherapy for anal cancer, 3DCRT or IMRT, give excellent long-term results. We evaluated results in community-based radiation centers. We retrospectively evaluated 281 patients treated with definitive chemo-radiotherapy for locoregional anal carcinoma, between 2006 and 2014. The 95% performed chemotherapy. Toxicity data, progression of the disease, need of colostomy during the follow-up period were evaluated. Global survival (GS), progression free survival (PFS), and free colostomy survival (CFS) were calculated with Kaplan-Meier methods. Mean age was 63.7 years with a mean follow-up of 60 months. One hundred and sixty nine patients received IMRT and 112 received 3DCRT. The total mean tumor dose was 54 Gy. The 80% experienced acute complications, and 56% required treatment interruption. There was no significant difference in GS, PFS, CFS or local control at two years between both groups. The IMRT had less treatment discontinuation (48% vs. 65%) (p = 0.0261). The IMRT group had a significant reduction in all acute toxicities ≥3 and late gastrointestinal, compared with those treated with 3DCRT. This series represents one of the largest 3DCRT vs. IMRT comparisons for the definitive treatment of anal cancer. The long-term results do not differ significantly depending on the RT technique. The IMRT reduces all toxicities ≥ grade 3 and the need for interruption compared to 3DCRT (AU)


Asunto(s)
Humanos , Neoplasias del Ano/radioterapia , Radioterapia Conformacional , Radioterapia de Intensidad Modulada , Estudios Retrospectivos , Toxicidad
17.
Rev. colomb. cancerol ; 21(2): 126-129, abr.-jun. 2017. graf
Artículo en Español | LILACS | ID: biblio-900461

RESUMEN

Resumen La incidencia de carcinoma escamocelular de próstata es del 0,5 al 1% de todas las lesiones neoplásicas de esta glándula. Por su rareza, no existen recomendaciones protocolizadas sobre el manejo de estos pacientes. Se reporta el caso de un paciente tratado en el Instituto con este diagnóstico, así como su desenlace a dos años de seguimiento y la revisión del tema. Reporte de caso: Paciente masculino de 79 anos de edad, con diagnóstico de carcinoma escamocelular infiltrante de próstata estadificado como T4NxMx. PSA de 2,64 y Gleason no determinable. Se descartó posible primario de órgano aledaño a la próstata y los estudios de extensión fueron negativos. Fue tratado con radioterapia externa como monoterapia y se utilizó técnica IMRT. Recibió una dosis en pelvis de 46 Gy en fracciones de 2 Gy día (PTV 1), posteriormente refuerzo en próstata y vesículas hasta 56 Gy (PTV 1,1) y en próstata hasta 76 Gy (PTV 1,1,1). A los dos años de seguimiento se documentaron lesiones pulmonares a las cuales se les practicó biopsia y el estudio anatomopatológico fue compatible con carcinoma escamocelular invasivo.


Abstract The incidence of squamous cell carcinoma of prostate is between 0.5-1% of all neoplastic lesions of this gland. Due to their rarity, there are no protocolised recommendations on the management of these patients. A report is presented on a patient with this diagnosis treated at our institution, its outcome at two years of follow-up, and a review of the subject. Case report: Male patient, 79 years old, diagnosed with invasive squamous cell carcinoma of the prostate. Staged as T4NxMx/IPSA 2.64/Gleason undeterminable. Work up studies were negative, and primaries from nearby organs were ruled out. He was treated with radiotherapy as monotherapy and was scheduled for an intensity-modulated radiotherapy (IMRT) technique, initially to the pelvis at a radiotherapy dose of 46 Gy 2Gy daily (PTV 1), further reinforcing prostate and vesicles up to 56 Gy (1.1 PTV), and finally to 76 Gy to prostate (PTV 1,1,1). With a follow-up of two years, lung lesions were found, which were biopsied and positive for squamous cell carcinoma.


Asunto(s)
Humanos , Masculino , Anciano , Próstata , Carcinoma de Células Escamosas , Radioterapia de Intensidad Modulada , Radioterapia , Biopsia
18.
Clin Transl Oncol ; 19(9): 1161-1167, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28374321

RESUMEN

BACKGROUND/PURPOSE: To evaluate the impact of intensity-modulated radiotherapy (IMRT) with intra-prostate fiducial markers image-guided radiotherapy (IGRT) on the incidence of late urinary toxicity compared to 3D conformal radiotherapy (3DCRT) for patients with prostate cancer (PC). METHODS AND MATERIALS: We selected 733 consecutive patients with localized PC treated with dose-escalation radiotherapy between 2001 and 2014. Eligibility criteria were radiation dose >72.0 Gy, no pelvic RT and minimum follow-up 24 months. 438 patients were treated with 3DCRT and 295 with IMRT. Acute and late urinary complications were assessed using the EORTC/RTOG and CTCAEs v3.0 definition. The Cox regression model was used to compare grade ≥2 urinary toxicity between both techniques. The median follow-up was 75 months (range 24-204). RESULTS: The median isocenter radiation dose was 78.7 Gy for 3DCRT and 80.7 Gy for IMRT/IGRT (p < 0.001). The 5-year incidence of late grade ≥2 urinary toxicity was 6.4% for IMRT and 10.8% for 3DCRT [hazard ratio (HR) 0.575, p = 0.056]. The corresponding 5-year estimates of late grade ≥2 hematuria were 2% for IMRT and 5.3% for 3DCRT (HR 0.296, p = 0.024). On multivariate analysis, the antecedent of prior transurethral resection of the prostate was also a strong predictor of a higher risk of urinary complications (HR 2.464, p = 0.002) and of hematuria (HR 5.196, p < 0.001). CONCLUSION: Compared with 3DCRT, high-dose IMRT/IGRT is associated with a lower rate of late urinary complications in spite of higher radiation dose.


Asunto(s)
Marcadores Fiduciales , Neoplasias de la Próstata/radioterapia , Traumatismos por Radiación/prevención & control , Radioterapia Guiada por Imagen/métodos , Radioterapia de Intensidad Modulada/efectos adversos , Vejiga Urinaria/efectos de la radiación , Anciano , Anciano de 80 o más Años , Humanos , Masculino , Persona de Mediana Edad , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos
19.
Rev. colomb. cancerol ; 21(1): 26-32, ene.-mar. 2017. graf
Artículo en Español | LILACS | ID: biblio-900450

RESUMEN

Resumen En la radioterapia de cabeza y cuello las glándulas salivales suelen recibir una dosis elevada de radiación, lo que provoca una disminución progresiva y, a partir de determinada dosis, irreversible de la secreción salival, entre otros efectos. La xerostomía o sensación de boca seca es el efecto secundario más frecuente tras la radioterapia de cabeza y cuello, el cual disminuye la calidad de vida de los pacientes al dificultar funciones como la fonación y la deglución. Dada la complejidad y la temprana aparición de este síntoma, su prevención es la solución más eficaz. Los avances de las últimas décadas tienen un papel imprescindible: la radioterapia de intensidad modulada, la administración de sustancias citoprotectoras y el autotransplante de glándula submandibular parecen limitar en cierta medida el efecto de la radiación y disminuir así la sensación de sequedad bucal.


Abstract Radiation therapy is a key component in the multidisciplinary treatment of head-and-neck malignancies. In these cases, salivary glands are irradiated with high-level doses, which, among other side effects, results in a progressive and irreversible decrease in the salivary output. Radiation-induced xerostomia is the most common side effect of the head and neck region after radiotherapy treatment, and highly impairs the patients' long-term quality of life, threatening physiological functions, essentially speaking and swallowing. Given the complexity and early appearance of this symptom, its prevention is the most effective solution. In the past decades, the development of new radiation delivery techniques, such as intensity-modulated radiotherapy (IMRT), along with the administration of radioprotective drugs and autologous submandibular gland transplantation, seem to reduce the dose reaching the salivary glands, which in turn improves the patients' perception of dry mouth.


Asunto(s)
Humanos , Xerostomía , Radioterapia de Intensidad Modulada , Radiación , Radioterapia , Terapéutica , Métodos , Cabeza , Boca , Cuello
20.
Phys Med ; 34: 1-6, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28108100

RESUMEN

Intensity modulated radiotherapy (IMRT) is one of the most modern radiation therapy treatment techniques. Although IMRT can deliver high and complex conformational doses to the tumor volume, its implementation requires rigorous quality assurance (QA) procedures that include a dosimetric pre-treatment verification of individual patient planning. This verification usually involves measuring a small volume of absolute dose with an ionization chamber and checking bi-dimensional fluency with an array of detectors. The planning technique has tri-dimensional characteristics, but no tridimensional dosimetry has been established in the clinical routine. One strategy to perform three-dimensional dosimetry is to use polymeric gels associated with magnetic resonance imaging to evaluate dose distribution. Here, we have compared the results of conventional QA procedures involving one- and two-dimensional dosimetry to the results of three-dimensional dosimetry conducted with MAGIC-f gel in 10 cases of prostate cancer IMRT planning. More specifically, we used the gamma index (3%/3mm) to compare the results of three-dimensional dosimetry to the expected dose distributions obtained with the treatment planning system. Except for one IMRT treatment plan, the gel dosimetry results agreed with the conventional quality control and provided an overview of dose distribution in the target volume.


Asunto(s)
Imagenología Tridimensional , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/radioterapia , Garantía de la Calidad de Atención de Salud , Radioterapia de Intensidad Modulada , Calibración , Geles , Humanos , Imagen por Resonancia Magnética , Masculino , Radiometría , Planificación de la Radioterapia Asistida por Computador
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