In HNSCC patients treated with IMRT, thyroid V50 highly predicts the risk of developing hypothyroidism. V50>60% puts patients at a significantly higher risk of becoming hypothyroid. This can be a useful dose constraint to consider during treatment planning.
Inhomogeneously broadened, non-Lorentzian water resonances have been observed in small image voxels of breast tissue. The non-Lorentzian components of the water resonance are likely produced by bulk magnetic susceptibility shifts caused by dense, deoxygenated tumor blood vessels (the ‘BOLD’ effect), but can also be produced by other characteristics of local anatomy and physiology, including calcifications and interfaces between different types of tissue. Here, we tested the hypothesis that detection of non-Lorentzian components of the water resonance with high spectral and spatial resolution (HiSS) MR imaging allows classification of breast lesions without the need to inject contrast agent. Eighteen malignant lesions and nine benign lesions were imaged with HiSS MRI at 1.5T. A new algorithm was developed to detect non-Lorentzian (or off-peak) components of the water resonance. After a Lorentzian fit was subtracted from the data, the largest peak in the residual spectrum in each voxel was identified as the major off-peak component of the water resonance. The difference in frequency between these off-peak components and the main water peaks, and their amplitudes were measured in malignant lesions, benign lesions, and breast fibroglandular tissue. Off-peak component frequencies were significantly different between malignant and benign lesions (p<0.001). Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance of HiSS off-peak component analysis compared to dynamic contrast enhanced (DCE) MRI parameters. The areas under the ROC curves for ‘DCE rapid uptake fraction’, ‘DCE washout fraction’, ‘off-peak component amplitude’, and ‘off-peak component frequency’ were 0.75, 0.83, 0.50, and 0.86, respectively. These results suggest that water resonance lineshape analysis performs well in the classification of breast lesions without contrast injection and could improve diagnostic accuracy of clinical breast MR exams. In addition, this approach may provide an alternative to DCEMRI in women who are at risk for adverse reactions to contrast media.
BackgroundA significant number of patients treated for head and neck squamous cell cancer (HNSCC) undergo enteral tube feeding. Data suggest that avoiding enteral feeding can prevent long-term tube dependence and disuse of the swallowing mechanism which has been linked to complications such as prolonged dysphagia and esophageal constriction. We examined detailed dosimetric and clinical parameters to better identify those at risk of requiring enteral feeding.MethodsOne hundred patients with advanced stage HNSCC were retrospectively analyzed after intensity-modulated radiation therapy (IMRT) to a median dose of 70 Gy (range: 60-75 Gy) with concurrent chemotherapy in nearly all cases (97%). Patients with significant weight loss (>10%) in the setting of severely reduced oral intake were referred for placement of a percutaneous endoscopic gastrostomy (PEG) tube. Detailed DVH parameters were collected for several structures. Univariate and multivariate analyses using logistic regression were used to determine clinical and dosimetric factors associated with needing enteral feeding. Dichotomous outcomes were tested using Fisher’s exact test and continuous variables between groups using the Wilcoxon rank-sum test.ResultsThirty-three percent of patients required placement of an enteral feeding tube. The median time to tube placement was 25 days from start of treatment, after a median dose of 38 Gy. On univariate analysis, age (p = 0.0008), the DFH (Docetaxel/5-FU/Hydroxyurea) chemotherapy regimen (p = .042) and b.i.d treatment (P = 0.040) (used in limited cases on protocol) predicted need for enteral feeding. On multivariate analysis, age remained the single statistically significant factor (p = 0.003) regardless of other clinical features (e.g. BMI) and all radiation planning parameters. For patients 60 or older compared to younger adults, the odds ratio for needing enteral feeding was 4.188 (p = 0.0019).ConclusionsOlder age was found to be the most significant risk factor for needing enteral feeding in patients with locally advanced HNSCC treated with multimodal treatment. Pending further validation, this would support maximizing early nutritional guidance, targeted supplementation, and symptomatic support for older adults (>60) undergoing chemoradiation. Such interventions and others (e.g. swallowing therapy) could possibly delay or minimize the use of enteral feeding, thereby helping avoid tube dependence and tube-associated long-term physiologic consequences.
ObjectivesLimiting radiation dose to the larynx can diminish effects of laryngeal dysfunction. However, no clear guidelines exist for defining the larynx and its substructures consistently on cross-sectional imaging. This study presents computed tomography (CT)- and magnetic resonance imaging (MRI)-based guidelines for contouring laryngeal organs-at-risk (OARs).Materials and MethodsStandardized guidelines for delineating laryngeal OARs were devised and used to delineate on CT and MRI for head-and-neck cancer patients. Volumetric comparisons were performed to evaluate consistency and reproducibility of guideline-based contours.ResultsFor the initial 5 patients the mean CT and MRI based larynx volume did not differ significantly between imaging modalities; 34.39 ± 9.85 vs. 35.01 ± 9.47 (p = .09). There was no statistical difference between the CT based mean laryngeal volume in the subsequent 44 patients compared to the initial 5 patients outlined on CT and the MRI scan (p = 0.53 and 0.62). The OAR volume for laryngeal substructures were not statistically different among patients or between imaging modalities. Once established, the guidelines were easy to follow.ConclusionThe guidelines developed provide a precise method for delineating laryngeal OARs. These guidelines need to be validated and clinical significance of outlining laryngeal substructures and dose-volume constraints should be investigated before routine implementation in clinic practice.
Purpose There is little published data on the technique and results of whole-field (WF) sequential-intensity-modulated radiotherapy (S-IMRT) for patients with head and neck squamous-cell carcinoma (HNSCC). We report the treatment outcomes, adverse events (AEs), and dosimetric parameters in local–regional advanced (LRA) HNSCC patients treated with the WF S-IMRT technique. Methods The IRB approved this retrospective study. Patients received WF S-IMRT with or without concomitant chemotherapy. Three separate IMRT plans corresponding to three planning target volumes were generated. This study reports patient and tumor characteristics; treatment-induced acute AEs based on CTCAE version 3.0; chronic AEs according to RTOG scale and treatment outcomes; local–regional control (LRC); distant metastases (DM); relapse-free survival (RFS); and overall survival (OS). Results Between January 2003 and December 2010, 103 patients with LRA HNSCC were treated either definitively or postoperatively with WF S-IMRT, with (99 patients) or without (4 patients) concurrent chemotherapy. The median age was 55 years (range 30–89). The median cumulative target dose was 70 Gy (range 60–75 Gy). At a median follow-up of 40 months (range 4–95 months), the 2- and 5-year rates of OS were 94% and 77%; RFS were 90% and 84%; LRC were 97% and 93%; and DM were 9% and 11%, respectively. Grade 3 acute AEs included mucositis (68%); dysphagia (35%); weight loss (19.6%); and xerostomia (7.8%). Chronic worst grade 3 AEs included xerostomia (21.9%); weight loss (12.8%); and dysphagia (12.5%). Chronic grade 3 AEs at last follow-up included weight loss (6.25%); dysphagia (6.2%); and xerostomia (6.2%). No patient had an acute or chronic grade 4 AE, brachial plexopathy, or spinal cord injury. Conclusion WF S-IMRT results in excellent tumor control and an acceptable toxicity profile in LRA HNSCC patients treated with this technique.
Brain metastases are the most common intracranial tumors in adults, accounting for over half of all lesions. Whole-brain radiation therapy (WBRT) has been a cornerstone in the management of brain metastases for decades. Recently, stereotactic radiosurgery (SRS) has been considered as a definitive or postoperative approach instead of WBRT, to minimize the risk of cognitive impairment that may be associated with WBRT. This is the case report of a 74-year-old female patient who was diagnosed with lung cancer in November, 2002, and histopathologically confirmed brain metastases in January, 2005. The patient received 5 treatments with Gamma Knife SRS for recurring brain metastases between 2005 and 2014. The patient remains highly functional, with stable intracranial disease at 10 years since first developing brain metastases, and with stable lung disease. Therefore, Gamma Knife SRS is a safe and effective treatment modality for patients with recurrent intracranial metastases, with durable local control and minimal cognitive impairment.
PurposeWe aimed to study the radiation induced brachial plexopathy in patients with head and neck squamous cell carcinoma (HNSCC) treated with Sequential Intensity Modulated Radiation Therapy (S-IMRT).Methods and materialsThis IRB approved study included 68 patients with HNSCC treated consecutively. Detailed dose volume histogram data was generated for ipsilateral and contralateral brachial plexus (BP) volumes receiving a specified dose (Vds) i.e. V50-V75 and dose in Gray covering specified percent of BP volume (Dvs) i.e. D5-D30 and maximum point doses (Dmax). To assess BP injury all patients’ charts were reviewed in detail for sign and symptoms of BP damage. Post-hoc comparisons were done using Tukey-Kramer method to account for multiple significance testing.ResultsThe mean and maximum doses to BP were significantly different (p < .05) based on tumor site, nodal status and tumor stage. The mean volume to the ipsilateral BP for V50, V60, V70, and V75 were 7.01 cc, 4.37 cc, 1.47 cc and 0.24 cc, respectively. The mean dose delivered to ≤5% of ipsilateral BP was 68.70 Gy (median 69.5Gy). None of the patients had acute or late brachial plexopathy or any other significant neurological complications, with a minimum follow up of two years (mean 54 months).ConclusionsIn this study cohort, at a minimum of two-years follow up, the mean dose of 68.7Gy, a median dose to 69.5Gy to ≤5% of ipsilateral BP, and a median Dmax of 72.96Gy did not result in BP injury when patients were treated with S-IMRT technique. However, longer follow up is needed.
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