ABSTRACT
Inhalant misuse and inhalant use disorder are global public health concern that impacts adolescents but can occur throughout life. Toluene is the most commonly misused inhalant. Toluene use leads to significant neuroanatomic, cognitive, and psychiatric deficits. The purpose of this study was to review and summarize the effects of toluene and present a case of a middle-aged patient with an inhalant use disorder. A literature review was conducted to evaluate imaging, neurocognitive, and psychiatric consequences of toluene misuse. The common imaging findings amongst those who misuse toluene were cerebral and cerebellar atrophy, ventricular dilation, loss of gray-white matter differentiation, corpus callosum thinning, and diffuse white matter changes. Concerning cognition, toluene misusers were shown to have deficits in intelligence, attention, memory, visuospatial function, and complex cognition. In addition, toluene users also commonly presented with apathy, flat affect, hallucinations, delusions, anxiety, depression, and insomnia. The neuroanatomical, neurocognitive, and psychiatric effects of toluene misuse are profound. These deficits can make inhalant use disorder difficult to treat. Therefore, evidence-based treatments that recognize and address these domain-specific neurocognitive deficits are needed.
ABSTRACT
BACKGROUND AND PURPOSE: Taste impairment is a common radiation-induced toxicity in head and neck cancer (HNC) patients acutely. However, data on the potential for recovery and the time dependent course of late taste impairment are limited. MATERIALS AND METHODS: As part of an IRB-approved observational prospective study, HNC patients underwent serial surveys including the MD Anderson Symptom Inventory - Head and Neck module (MDASI-HN). For our analysis, we extracted MDASI-HN taste item results from oropharyngeal cancer patients treated with intensity-modulated radiotherapy or volumetric modulated arc therapy and at least two taste assessments after ≥1 year from end of radiotherapy (RT). RESULTS: 1214 MDASI taste items from 326 patients between 1 and 13 years post-RT were included. Median prescribed dose to the high-dose clinical target volume (CTV1) was 66.0 Gy, with 180 patients (55%) receiving chemotherapy. Taste markedly improved in the first years from end of RT, but plateaued after year 5. In patients with taste assessment in subsequent years, a significant reduction in taste impairment was found from the second to the third year (p = 0.001) and tended towards significance from the third to the fourth year (p = 0.058). Multivariate analysis revealed treatment site as significant factor in the sixth year from RT and CTV1 dose and age in the seventh year. CONCLUSION: Radiation-induced taste impairment may improve over an extended time interval, but becomes relatively stable from year 5 post-RT. Direct characterization of RT-induced taste impairment and the calculation of normal tissue complication probability should include consideration of the time-dependent course in taste recovery.
ABSTRACT
PURPOSE: To evaluate 2 published normal tissue complication probability models for radiation-induced hypothyroidism (RHT) on a large cohort of oropharyngeal carcinoma (OPC) patients who were treated with intensity-modulated radiation therapy (IMRT). METHODS AND MATERIALS: OPC patients treated with retrievable IMRT Digital Imaging and Communications in Medicine (DICOMs) data and available baseline and follow-up thyroid function tests were included. Mean dose (Dmean) to the thyroid gland (TG) and its volume were calculated. The study outcome was clinical HT at least 6 months after radiation therapy, which was defined as grade ≥2 HT per Common Terminology Criteria for Adverse Events grading system (symptomatic hypothyroidism that required thyroid replacement therapy). Regression analyses and Wilcoxon rank-sum test were used. Receiver operating characteristic curves and area under the curve for the fitted model were calculated. RESULTS: In the study, 360 OPC patients were included. The median age was 58 years. Most tumors (51%) originated from the base of tongue. IMRT-split field was used in 95%, and median radiation therapy dose was 69.96 Gy. In the study, 233 patients (65%) developed clinical RHT that required thyroid replacement therapy. On multivariate analysis higher Dmean and smaller TG volume maintained the statistically significant association with the risk of clinical RHT (P < .0001). Dmean was significantly higher in patients with clinical RHT versus those without (50 vs 42 Gy, P < .0001). Patients with RHT had smaller TG volume compared with those without (11.8 compared with 12.8 mL, P < .0001). AUC of 0.72 and 0.66 were identified for fitted model versus for the applied Boomsma et al and Cella et al models, respectively. CONCLUSIONS: Volume and Dmean of the TG are important predictors of clinical RHT and shall be integrated into normal tissue complication probability models for RHT. Dmean and thyroid volume should be considered during the IMRT plan optimization in OPC patients.
