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1.
Crit Rev Oncog ; 29(3): 5-24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38683151

RESUMO

Squamous cell carcinoma of the oral cavity presents a significant global health burden, primarily due to risk factors such as tobacco smoking, smokeless tobacco use, heavy alcohol consumption, and betel quid chewing. Common clinical manifestations of oral cavity cancer include visible lesions and sores, often accompanied by pain in advanced stages. Diagnosis relies on a comprehensive assessment involving detailed history, physical examination, and biopsy. Ancillary imaging studies and functional evaluations aid in accurate staging and facilitate treatment planning. Prognostic information is obtained from histopathological factors, such as tumor grade, depth of invasion, lymphovascular invasion, and perineural invasion. Notably, lymph node metastasis, found in approximately half of the patients, carries significant prognostic implications. Effective management necessitates a multidisciplinary approach to optimize patient outcomes. Surgical resection is the backbone of treatment, aimed at complete tumor removal while preserving functional outcomes. Adjuvant therapies, including radiation and chemotherapy, are tailored according to pathological factors. Further work in risk stratification and treatment is necessary to optimize outcomes in squamous cell carcinoma of the oral cavity.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Neoplasias Bucais/terapia , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/etiologia , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/terapia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/etiologia , Carcinoma de Células Escamosas/patologia , Gerenciamento Clínico , Prognóstico , Fatores de Risco
2.
Crit Rev Oncog ; 29(3): ix-x, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38683148
3.
Radiat Oncol ; 19(1): 13, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38263237

RESUMO

BACKGROUND: To assess the feasibility of CBCT-based adaptive intensity modulated proton therapy (IMPT) using automated planning for treatment of head and neck (HN) cancers. METHODS: Twenty HN cancer patients who received radiotherapy and had pretreatment CBCTs were included in this study. Initial IMPT plans were created using automated planning software for all patients. Synthetic CTs (sCT) were then created by deforming the planning CT (pCT) to the pretreatment CBCTs. To assess dose calculation accuracy on sCTs, repeat CTs (rCTs) were deformed to the pretreatment CBCT obtained on the same day to create deformed rCT (rCTdef), serving as gold standard. The dose recalculated on sCT and on rCTdef were compared by using Gamma analysis. The accuracy of DIR generated contours was also assessed. To explore the potential benefits of adaptive IMPT, two sets of plans were created for each patient, a non-adapted IMPT plan and an adapted IMPT plan calculated on weekly sCT images. The weekly doses for non-adaptive and adaptive IMPT plans were accumulated on the pCT, and the accumulated dosimetric parameters of two sets were compared. RESULTS: Gamma analysis of the dose recalculated on sCT and rCTdef resulted in a passing rate of 97.9% ± 1.7% using 3 mm/3% criteria. With the physician-corrected contours on the sCT, the dose deviation range of using sCT to estimate mean dose for the most organ at risk (OARs) can be reduced to (- 2.37%, 2.19%) as compared to rCTdef, while for V95 of primary or secondary CTVs, the deviation can be controlled within (- 1.09%, 0.29%). Comparison of the accumulated doses from the adaptive planning against the non-adaptive plans reduced mean dose to constrictors (- 1.42 Gy ± 2.79 Gy) and larynx (- 2.58 Gy ± 3.09 Gy). The reductions result in statistically significant reductions in the normal tissue complication probability (NTCP) of larynx edema by 7.52% ± 13.59%. 4.5% of primary CTVs, 4.1% of secondary CTVs, and 26.8% tertiary CTVs didn't meet the V95 > 95% constraint on non-adapted IMPT plans. All adaptive plans were able to meet the coverage constraint. CONCLUSION: sCTs can be a useful tool for accurate proton dose calculation. Adaptive IMPT resulted in better CTV coverage, OAR sparing and lower NTCP for some OARs as compared with non-adaptive IMPT.


Assuntos
Transtornos da Coagulação Sanguínea , Neoplasias de Cabeça e Pescoço , Terapia com Prótons , Radioterapia de Intensidade Modulada , Humanos , Prótons , Tomografia Computadorizada de Feixe Cônico
5.
Front Oncol ; 13: 1147474, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36937396

RESUMO

Objectives: Radiation therapy (RT) is an integral part of treatment of head/neck cancer (HNC) but is associated with many toxicities. We sought to evaluate sociodemographic, pathologic, and clinical factors associated with emergency department (ED) visits, hospital admissions (HA), and RT breaks in HNC patients undergoing curative-intent RT. Methods: We completed a Level 3 (Oxford criteria for evidence-based medicine) analysis of a cohort of HNC patients who underwent curative-intent RT at our institution from 2013 to 2017. We collected demographic characteristics and retrospectively assessed for heavy opioid use, ED visits or HA during RT as well as RT breaks. Treatment breaks were defined as total days to RT fractions ratio ≥1.6. Multivariable stepwise logistic regression analyses were done to determine the association of various sociodemographic, pathologic, and clinical characteristics with ED visits, HA and RT treatment breaks. Results: The cohort included 376 HNC patients (294 male, 82 female, median age 61). On multivariable analysis, significant factors associated with ED visits during RT were heavy opioid use and black race. Receipt of concomitant chemotherapy was the only factor associated with hospital admissions during RT. Advanced age, lower socioeconomic class, glandular site, and receipt of chemotherapy were all independently associated with RT breaks. Lower cancer stage and lack of substance abuse history were independently associated with lack of treatment breaks. Conclusion: HNC patients with factors such as heavy opioid use, Black race, receipt of concomitant chemotherapy, and lower socioeconomic class may require closer monitoring during RT.

6.
Am Surg ; 89(4): 920-926, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34732085

RESUMO

BACKGROUND: For selected patients with early-stage breast cancer (BC), intraoperative radiation therapy (IORT) has emerged as a convenient alternative to standard whole breast irradiation (WBI). We report a single institution experience with IORT in terms of oncologic outcomes, toxicities, and cosmesis. METHODS: Clinicopathological and perioperative outcomes of patients who underwent IORT for early-stage BC at a public hospital from 2017 to 2020 were retrospectively retrieved. Toxicity was categorized to acute or chronic based on 6 months post-IORT cutoff. RESULTS: 85 patients underwent IORT and had complete data, aged 49-85 years (mean 62). Intraoperative radiation therapy added 23 minutes on average to the total operative time. Final stage was 0, I, and II in 40%, 58.9%, and 1.1% of patients, respectively. Mean tumor size was 0.8 cm (range .1-2.1), with ductal histology comprising 94% of cases. Surgical margins were positive in 2 patients, and adjuvant WBI was required in 5 patients. After a median follow-up of 17 months (range 3-41), none of the patients had local recurrence and no mortality was recorded. Early wound complications included wound dehiscence (n = 1), seroma/hematoma (n = 15), and re-operation with loss of nipple-areola complex (n = 1). Chronic skin toxicities were reported in 10 (12%) patients and good or excellent cosmetic outcome was reported in 93% of patients. CONCLUSIONS: Utilizing IORT among low-risk early BC patients may be a safe and more convenient alternative to traditional WBI, with low toxicity rate, acceptable cosmetic results, and good oncologic outcomes at 17 months. Longer follow-up and further prospective controlled studies are needed to confirm these findings.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/radioterapia , Neoplasias da Mama/cirurgia , Neoplasias da Mama/patologia , Estudos Retrospectivos , Mastectomia Segmentar/métodos , Radioterapia Adjuvante/efeitos adversos , Radioterapia Adjuvante/métodos , Cuidados Intraoperatórios/métodos , Recidiva Local de Neoplasia/cirurgia
7.
Brachytherapy ; 21(6): 896-903, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36137939

RESUMO

PURPOSE: I125 Eye Plaque brachytherapy is the standard treatment for medium-sized uveal melanomas (UM). Patients develop radiation toxicities (RTT), including radiation maculopathy (RM), radiation neovascular glaucoma/iris neovascularization (RNGI) and radiation optic neuropathy (RON). We aim to investigate demographics, pretreatment tumor characteristics and posttreatment complications as predictors of RTT. METHODS AND MATERIALS: An IRB-approved single-institution retrospective chart review was performed from 2011 to 2019 for patients with posterior UM treated with brachytherapy. We collected demographics, pretreatment tumor characteristics and posttreatment complications. Univariate analysis (UVA) and multivariate analysis (MVA) were performed using logistic regression model. Hazard ratios (HR) and corresponding p-values were reported. All tests were two-sided; statistical significance was considered when p<0.05. RESULTS: Two hundred and fifty eight patients were evaluated. Median follow-up was 33.50 months (range 3.02-97.31). 178 patients (69.0%) had RTT. 131 patients (50.8%) developed RM. Fifty-six patients (21.7%) developed RON. Nineteen patients (7.4%) developed RNGI. UVA found shorter distance to fovea (DF) (p = 0.04), posttreatment exudative retinal detachment (PERD) (p = 0.001) and posttreatment vitreous hemorrhage (PVH) (p = 0.001) are associated with RTT. MVA found shorter DF (HR=1.03, p = 0.04), PERD (HR=2.52, p = 0.01) and PVH (HR=3.34, p = 0.006) are associated with RTT. MVA found female sex (HR=1.731, p = 0.031) and tumor height (HR=1.13, p = 0.013) are associated with RM and pretreatment retinal detachment (HR=3.41, p<0.001) is associated with RON. CONCLUSIONS: Shorter DF, PERD and PVH are associated with RTT; female sex and tumor height are associated with RM and tumor height is associated with RON. These findings serve as prognostic tools to counsel patients and promote early intervention in management of RTT.


Assuntos
Braquiterapia , Doenças do Nervo Óptico , Lesões por Radiação , Descolamento Retiniano , Doenças Retinianas , Neoplasias Uveais , Humanos , Feminino , Braquiterapia/métodos , Descolamento Retiniano/complicações , Estudos Retrospectivos , Neoplasias Uveais/radioterapia , Neoplasias Uveais/patologia , Lesões por Radiação/etiologia , Hemorragia Vítrea/complicações , Doenças do Nervo Óptico/etiologia , Doenças Retinianas/etiologia , Complicações Pós-Operatórias
8.
J Surg Orthop Adv ; 31(2): 113-118, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35820098

RESUMO

Prophylactic radiotherapy (XRT) is a commonly used treatment to decrease heterotopic ossification (HO) in patients with traumatic hip injuries. We conducted a retrospective review of patients at risk for HO who underwent XRT. Of the patients reviewed, 27.3% developed radiographic HO, 11.2% developed symptoms, and 2.0% required resection surgery. Patients were divided into primary (n = 71) and secondary prophylaxis (n = 27) cohorts. In the primary group, 25.0% developed radiographic HO, 5.6% developed symptoms, and 0 required surgery. In the secondary cohort, 33.3% of patients developed new radiographic HO, and 25.9% were symptomatic: four had a Brooker score of 3, and three had a score of 4 (p = 0.03), and 7.4% required surgical resection. (Journal of Surgical Orthopaedic Advances 31(2):113-118, 2022).


Assuntos
Fraturas Ósseas , Ossificação Heterotópica , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Humanos , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/prevenção & controle , Estudos Retrospectivos , Fatores de Risco
9.
Cureus ; 14(2): e22463, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35345685

RESUMO

Objective The objective of this study is to contrast the predictive ability of targeted muscle groups as radiographic proxies of sarcopenia on computerized tomography (CT) with body mass index (BMI) in head and neck cancer patients (H&NCP) undergoing radiation at a safety net hospital, and to evaluate sarcopenia with survival, local progression, toxicities and treatment delays. Methods A retrospective review included 52 H&NCP treated between 2017-2019. The posterior neck muscles (PN), sternocleidomastoids (SCM), and their summed volume (AM) were contoured at C3 on patients' pre-treatment CT scans, then normalized to obtain skeletal muscle index (MI) values. Pre-treatment BMI was also evaluated. Cutoffs for sarcopenia were determined by receiver operating characteristic curves. Overall survival and local recurrence-free survival were evaluated by Kaplan-Meier. Acute grade 3 or higher toxicities were evaluated by binomial logistic regression. Results Using all neck muscles (AM-MI) produced the best model for predicting outcomes, outperforming individual muscle groups and BMI. Local progression-free survival was worse in sarcopenic patients at 25.81 months versus 35.40 months (p=0.026). Acute grade 3 or higher toxicities were associated with sarcopenia (p=0.005). Conclusions In this small, retrospective single-institution experience at a safety net hospital, a single axial slice of the combined sternocleidomastoids and paravertebral muscles at C3 performed better than either muscle group alone or pre-treatment BMI at predicting oncologic outcomes.

10.
Ocul Oncol Pathol ; 8(3): 175-180, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37431398

RESUMO

Introduction: Iodine-125 brachytherapy is an effective eye-sparing treatment for uveal melanoma. Previous work has shown that uveal melanomas cluster into distinct molecular classes based on gene expression profiles - discriminating low-grade from high-grade tumors. Our objective was to identify clinical and molecular predictors of local recurrence (LR) and progression-free survival (PFS). Methods: We constructed a retrospective database of uveal melanoma patients from the University of Miami's electronic medical records that were treated between January 8, 2012, and January 5, 2019, with either COMS-style or Eye Physics plaque. Data on tumor characteristics, pretreatment retinal complications, post-plaque treatments, LR, and PFS were collected. Univariate and multivariate Cox models for cumulative incidence of LR and PFS were conducted using SAS version 9.4. Results: We identified 262 patients, with a median follow-up time of 33.5 months. Nineteen patients (7.3%) had LR, and 56 patients (21.4%) were classified as PFS. We found that ocular melanocytosis (hazard ratio = 5.55, p < 0.001) had the greatest impact on PFS. Genetic expression profile did not predict LR outcomes (hazard ratio = 0.51, p = 0.297). Conclusion: These findings help physicians identify predictors for short-term brachytherapy outcomes, allowing better shared decision making with patients preoperatively when deciding between brachytherapy versus enucleation. Patients stratified to higher risk groups based on preoperative characteristics such as ocular melanocytosis should be monitored more closely. Future studies must validate these findings using a prospective cohort study.

11.
J Orthop Trauma ; 36(2): e56-e61, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34050084

RESUMO

OBJECTIVES: To examine the efficacy and safety of radiotherapy for the prevention of heterotopic ossification (HO) about the elbow. DESIGN: Retrospective chart review. SETTING: Level 1 trauma center. PATIENTS/PARTICIPANTS: Two hundred and twenty-nine patients who received prophylactic radiotherapy (XRT) over a 15-year period were identified. Patients were included if they received XRT to the elbow joint and had at least 12 weeks of follow-up after XRT. Fifty-four patients were ultimately included. INTERVENTION: All patients were treated with a single dose of 7 Gy. Ninety-eight percentage of patients received XRT within 24 hours after surgery, and all patients received XRT within 72 hours after surgery. MAIN OUTCOMES MEASUREMENTS: The primary study measures evaluated were the presence or absence of clinically symptomatic HO and the presence of radiographic HO after XRT to the elbow joint. RESULTS: Eighteen patients were treated with XRT after a traumatic injury requiring surgery (primary prophylaxis), and 36 were treated with XRT after excision surgery to remove HO which had already formed (secondary prophylaxis). In the primary cohort, 16.7% developed symptomatic HO after XRT and 11.1% required surgery to resect the heterotopic bone. In the secondary cohort, 11.1% developed symptomatic HO after surgery and XRT and 5.5% required resection surgery. No secondary malignancies were identified. CONCLUSIONS: Our findings suggest that XRT for elbow HO may be safe and effective for both primary and secondary HO. XRT for HO was not shown to be associated with radiation-induced sarcoma in this series, at least in the short term. Further study in a large patient population with extended follow-up is required to better characterize populations at high risk for development of HO and secondary malignancy. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Articulação do Cotovelo , Ossificação Heterotópica , Cotovelo , Articulação do Cotovelo/diagnóstico por imagem , Articulação do Cotovelo/cirurgia , Humanos , Ossificação Heterotópica/etiologia , Ossificação Heterotópica/prevenção & controle , Ossificação Heterotópica/radioterapia , Complicações Pós-Operatórias/prevenção & controle , Estudos Retrospectivos
12.
Front Oncol ; 11: 737901, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34737954

RESUMO

PURPOSE: To assess the performance of a proton-specific knowledge-based planning (KBP) model in the creation of robustly optimized intensity-modulated proton therapy (IMPT) plans for treatment of advanced head and neck (HN) cancer patients. METHODS: Seventy-three patients diagnosed with advanced HN cancer previously treated with volumetric modulated arc therapy (VMAT) were selected and replanned with robustly optimized IMPT. A proton-specific KBP model, RapidPlanPT (RPP), was generated using 53 patients (20 unilateral cases and 33 bilateral cases). The remaining 20 patients (10 unilateral and 10 bilateral cases) were used for model validation. The model was validated by comparing the target coverage and organ at risk (OAR) sparing in the RPP-generated IMPT plans with those in the expert plans. To account for the robustness of the plan, all uncertainty scenarios were included in the analysis. RESULTS: All the RPP plans generated were clinically acceptable. For unilateral cases, RPP plans had higher CTV_primary V100 (1.59% ± 1.24%) but higher homogeneity index (HI) (0.7 ± 0.73) than had the expert plans. In addition, the RPP plans had better ipsilateral cochlea Dmean (-5.76 ± 6.11 Gy), with marginal to no significant difference between RPP plans and expert plans for all other OAR dosimetric indices. For the bilateral cases, the V100 for all clinical target volumes (CTVs) was higher for the RPP plans than for the expert plans, especially the CTV_primary V100 (5.08% ± 3.02%), with no significant difference in the HI. With respect to OAR sparing, RPP plans had a lower spinal cord Dmax (-5.74 ± 5.72 Gy), lower cochlea Dmean (left, -6.05 ± 4.33 Gy; right, -4.84 ± 4.66 Gy), lower left and right parotid V20Gy (left, -6.45% ± 5.32%; right, -6.92% ± 3.45%), and a lower integral dose (-0.19 ± 0.19 Gy). However, RPP plans increased the Dmax in the body outside of CTV (body-CTV) (1.2 ± 1.43 Gy), indicating a slightly higher hotspot produced by the RPP plans. CONCLUSION: IMPT plans generated by a broad-scope RPP model have a quality that is, at minimum, comparable with, and at times superior to, that of the expert plans. The RPP plans demonstrated a greater robustness for CTV coverage and better sparing for several OARs.

13.
Brachytherapy ; 20(6): 1289-1295, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34193361

RESUMO

PURPOSE: Tilting of the posterior plaque margin during eye plaque brachytherapy can lead to tumor underdosing and increased risk of local recurrence. We performed a quantitative analysis of the dosimetric effects of plaque tilt as a function of tumor position, basal dimension, height and plaque type using 3D treatment planning software. MATERIALS AND METHODS: Posterior and anterior tumors with largest basal dimensions of 6, 12 and 18 mm and heights of 4, 7 and 10 mm were modeled. Both Eye Physics and COMS plaques were simulated and uniformly loaded. Plans were normalized to 85 Gy at the tumor apex. Posterior plaque tilts of 1, 2, 3 and 4 mm were simulated. RESULTS: Volumetric coverage is more sensitive to tilt than the area coverage. Wide, flat tumors are more susceptible to tilt. Apical dose changed significantly as a function of tumor height and diameter. No other parameter exhibited significant differences. Posterior tumors are slightly more susceptible to tilt due to the use of notched plaques. Plaque type does not significantly alter the effect of plaque tilt. CONCLUSIONS: Wide, flat tumors are the most susceptible to plaque tilt. Tumor location or plaque type does not have a significant effect on dosimetry changes from plaque tilt. Robust clinical procedures such as the use of mattress sutures, pre- and post-implant ultrasound and post-implant dosimetry can all mitigate the risk associated with plaque tilt.


Assuntos
Braquiterapia , Neoplasias Oculares , Melanoma , Braquiterapia/métodos , Humanos , Radiometria , Dosagem Radioterapêutica
14.
Head Neck ; 43(10): 2973-2984, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34143542

RESUMO

BACKGROUND: We had previously analyzed the variables that determine the rates of opioid use at 1-year postradiotherapy in patients with head and neck cancer. Here we analyze the variables associated with opioid abstinence during and in the 12 months after radiotherapy at our institution. METHODS: We identified a cohort of patients with head and neck cancer who received radiotherapy as part of curative treatment at our institution. Logistic regression analyses were performed to determine socioeconomic and clinical factors associated with opioid abstinence. RESULTS: The cohort included 376 patients. On multivariable analysis, patients from an upper-income class (p = 0.004), black race (p = 0.004), older (p = 0.008), with dependent children (p < 0.001) or receiving surgery (p = 0.002) were more likely to abstain from opioids, while patients using analgesic mouthwash (p = 0.009) or higher pain scale (p = 0.002) were less likely. CONCLUSION: Socioeconomic and treatment characteristics are associated with opioid abstinence during and following radiation treatment in patients with head and neck cancer.


Assuntos
Neoplasias de Cabeça e Pescoço , Transtornos Relacionados ao Uso de Opioides , Analgésicos Opioides/uso terapêutico , Criança , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Medição da Dor , Estudos Retrospectivos
15.
Int J Part Ther ; 7(4): 29-41, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33829071

RESUMO

PURPOSE: Anatomical changes and patient setup uncertainties during intensity modulated proton therapy (IMPT) of head and neck (HN) cancers demand frequent evaluation of delivered dose. This work investigated a cone-beam computed tomography (CBCT) and deformable image registration based therapy workflow to demonstrate the feasibility of proton dose calculation on synthetic computed tomography (sCT) for adaptive IMPT treatment of HN cancer. MATERIALS AND METHODS: Twenty-one patients with HN cancer were enrolled in this study, a retrospective institutional review board protocol. They had previously been treated with volumetric modulated arc therapy and had daily iterative CBCT. For each patient, robust optimization (RO) IMPT plans were generated using ±3 mm patient setup and ±3% proton range uncertainties. The sCTs were created and the weekly delivered dose was recalculated using an adaptive dose accumulation workflow in which the planning computed tomography (CT) was deformably registered to CBCTs and Hounsfield units transferred from the planning CT. Accumulated doses from ±3 mm/±3% RO-IMPT plans were evaluated using clinical dose-volume constraints for targets (clinical target volume, or CTV) and organs at risk. RESULTS: Evaluation of weekly recalculated dose on sCTs showed that most of the patient plans maintained target dose coverage. The primary CTV remained covered by the V95 > 95% (95% of the volume receiving more than 95% of the prescription dose) worst-case scenario for 84.5% of the weekly fractions. The oral cavity accumulated mean dose remained lower than the worst-case scenario for all patients. Parotid accumulated mean dose remained within the uncertainty bands for 18 of the 21 patients, and all were kept lower than RO-IMPT worst-case scenario for 88.7% and 84.5% for left and right parotids, respectively. CONCLUSION: This study demonstrated that RO-IMPT plans account for most setup and anatomical uncertainties, except for large weight-loss changes that need to be tracked throughout the treatment course. We showed that sCTs could be a powerful decision tool for adaptation of these cases in order to reduce workload when using repeat CTs.

16.
Phys Med ; 81: 1-8, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33278764

RESUMO

BACKGROUND: Newer technology for stereotactic radiosurgery (SRS) should be assessed for different multi-leaf collimators (MLC). OBJECTIVE: Assess plan quality of an automated, frameless, linear accelerator based (linac) planning and delivery system (HyperArc) for SRS using both standard MLC (SMLC) and high definition MLC (HDMLC) compared to a cobalt-60 based SRS system (Gamma Knife, GK). METHODS: We re-planned twenty GK Perfexion-treated SRS patients (27 lesions) for HyperArc using SMLC and HDMLC. We assessed plan quality using the following metrics: gradient index (GI), Paddick and RTOG conformity indices (CIPaddick, CIRTOG), volume receiving half of prescription isodose (PIVhalf) and maximum dose to 0.03 cc for brainstem, optic chiasm and optic nerves, and V12Gy for brain-GTV. RESULTS: Linac plans had better conformity with HDMLC being most conformal. GK exhibited better GI. PIVhalf demonstrated no statistically significant difference between HDMLC and GK, and SMLC was nominally worse than GK. Mean PIVhalf was generally 0.85 cc larger for SMLC than HDMLC. For TV > 1.0 cc, the relative differences in CIRTOG, GI, and PIVhalf for SMLC vs. HDMLC were less than 21%. For TV less than < 1.0 cc, there were more obvious relative differences for SMLC vs. HDMLC in CIRTOG (mean 146%, max 700%), GI (mean 49%, max 162%), and PIVhalf (mean 77%, max 522%). Organ at risk doses were met in all plans. CONCLUSIONS: New linac-based plans positively compare to GK plans overall. HDMLC should be strongly considered for treatment of lesions < 1.0 cc given the significant improvements in conformity and PIVhalf over SMLC.


Assuntos
Neoplasias Encefálicas , Radiocirurgia , Radioterapia de Intensidade Modulada , Encéfalo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirurgia , Humanos , Aceleradores de Partículas , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Base do Crânio
18.
Brachytherapy ; 19(2): 249-254, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32061535

RESUMO

PURPOSE: A common treatment planning technique for eye plaque brachytherapy is to model the tumor as an ellipse. For posterior tumors near the optic disc and fovea, this approach may lead to overlap between tumor and the organ at risk (OAR). We hypothesized that a superior plan can be generated by modeling the actual tumor shape. MATERIALS AND METHODS: Forty eye plaque patients with tumors <1 cm from the optic disc and fovea were selected. Two treatment plans were generated for each patient: an elliptical tumor model plan and a true tumor model plan. Dosimetric data were collected for each plan, and Wilcoxon signed-rank tests were used to asses any statistically significant differences. RESULTS: Equivalent tumor coverage was confirmed between the elliptical and true tumor plans for all patients. Qualitative analysis showed greater dosimetric differences between plans as the distance from the OARs increased from 0 to 2 mm but the largest differences were observed between 2 and 4 mm. Minimal differences between models were seen beyond 4 mm. Statistically significant dosimetric improvements were found for tumors <4 mm from the fovea and <2 mm from the optic disc. CONCLUSIONS: Intuitively, accurate modeling of the tumor accounting for irregularities in the shape should result in a more conformal plan and an overall reduction in OAR dose. However, this technique is only beneficial for tumors that are within 4 mm of the fovea or optic disc. An elliptical tumor model allows for an acceptable plan unless the tumor is located posteriorly and has an irregular shape.


Assuntos
Braquiterapia , Neoplasias Oculares/patologia , Neoplasias Oculares/radioterapia , Melanoma/patologia , Melanoma/radioterapia , Planejamento da Radioterapia Assistida por Computador/métodos , Humanos , Disco Óptico , Órgãos em Risco , Doses de Radiação , Dosagem Radioterapêutica
19.
Head Neck ; 42(4): 608-624, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31785054

RESUMO

BACKGROUND: No study has determined the incidence of long-term opioid use, or risk factors for long-term use, ≥1 year after radiotherapy. METHODS: Medical records of 276 head/neck cancer patients were retrospectively assessed for persistent opioid use 1-year after curative-intent radiotherapy. Numerous potential risk factors were assessed and the physicians' documented reasons for continued use were qualitatively categorized as suspected opioid use disorder (OUD) or as medically indicated for control of ongoing pain. RESULTS: Of note, 20 of 276 patients continued using opioids long-term. High maximum opioid dose and the use of opioids and/or psychotropics/non-opioid analgesics at the radiation oncology intake visit were associated with this outcome. Three patients continued due to suspected OUD and 17 due to medical indications. CONCLUSION: Of note, 7.2% of patients developed long-term opioid use, which was associated with high maximum opioid dose and early initiation of opioids and/or psychotropics/non-opioid analgesics. Physicians cited medical indications as the primary reason for continued use.


Assuntos
Neoplasias de Cabeça e Pescoço , Transtornos Relacionados ao Uso de Opioides , Radioterapia (Especialidade) , Analgésicos Opioides/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Estudos Retrospectivos
20.
Pract Radiat Oncol ; 10(5): 339-344, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31783168

RESUMO

The hybrid 0.35T magnetic resonance imaging (MRI) and radiation therapy system functions in part as a simulation platform for treatment planning. We have found that the images generated are particularly helpful for planning of stereotactic radiation therapy for spinal metastases. Advantages include the following: (1) Low-field MRI mitigates magnetic susceptibility artifacts caused by spinal hardware. (2) Volumetric pulse sequence provides isotropic images for improved target delineation. (3) Wide-bore MRI in the radiation oncology department allows for easy simulation in treatment position for accurate fusion across imaging modalities. (4) When patients are treated on the MRI and radiation therapy hybrid device, adaptive radiation therapy is available for special situations to avoid mobile organs at risk.


Assuntos
Neoplasias da Coluna Vertebral , Humanos , Imageamento por Ressonância Magnética , Radiocirurgia , Planejamento da Radioterapia Assistida por Computador , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Neoplasias da Coluna Vertebral/radioterapia , Neoplasias da Coluna Vertebral/cirurgia , Coluna Vertebral
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