CT-based radiomic signatures for prediction of pathologic complete response in esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy.

The objective of this study was to build models to predict complete pathologic response (pCR) after neoadjuvant chemoradiotherapy (nCRT) in esophageal squamous cell carcinoma (ESCC) patients using radiomic features. A total of 55 consecutive patients pathologically diagnosed as having ESCC were included in this study. Patients were divided into a training cohort (44 patients) and a testing cohort (11 patients). The logistic regression analysis using likelihood ratio forward selection was performed to select the predictive clinical parameters for pCR, and the least absolute shrinkage and selection operator (LASSO) with logistic regression to select radiomic predictors in the training cohort. Model performance in the training and testing groups was evaluated using the area under the receiver operating characteristic curves (AUC). The multivariate logistic regression analysis identified no clinical predictors for pCR. Thus, only radiomic features selected by LASSO were used to build prediction models. Three logistic regression models for pCR prediction were developed in the training cohort, and they were able to predict pCR well in both the training (AUC, 0.84-0.86) and the testing cohorts (AUC, 0.71-0.79). There were no differences between these AUCs. We developed three predictive models for pCR after nCRT using radiomic parameters and they demonstrated good model performance.

Transcriptome analysis of differential gene expression in Dichomitus squalens during interspecific mycelial interactions and the potential link with laccase induction.

Interspecific mycelial interactions between white rot fungi are always accompanied by an increased production of laccase. In this study, the potential of the white rot fungus Dichomitus squalens to enhance laccase production during interactions with two other white rot fungi, Trametes versicolor or Pleurotus ostreatus, was assessed. To probe the mechanism of laccase induction and the role that laccase plays during combative interaction, we analyzed the differential gene expression profile of the laccase induction response to stressful conditions during fungal interaction. We further confirmed the expression patterns of 16 selected genes by qRT-PCR analysis. We noted that many differentially expressed genes (DEGs) encoded proteins that were involved in xenobiotic detoxification and reactive oxygen species (ROS) generation or reduction, including aldo/keto reductase, glutathione S-transferases, cytochrome P450 enzymes, alcohol oxidases and dehydrogenase, manganese peroxidase and laccase. Furthermore, many DEG-encoded proteins were involved in antagonistic mechanisms of nutrient acquisition and antifungal properties, including glycoside hydrolase, glucanase, chitinase and terpenoid synthases. DEG analyses effectively revealed that laccase induction was likely caused by protective responses to oxidative stress and nutrient competition during interspecific fungal interactions.

Pattern of radiation-induced thyroid gland changes in nasopharyngeal carcinoma patients in 48 months after radiotherapy.

OBJECTIVES: Radiation-induced hypothyroidism is the most common thyroid disorder after radiotherapy in nasopharyngeal carcinoma (NPC) patients. This study evaluated the pattern of radiation-induced thyroid gland changes in 48 months after radiotherapy in NPC patients and the association of hypothyroidism incidence with thyroid dose. METHODS: Fifty-six NPC patients treated by intensity modulated radiotherapy in 2013 were recruited. All patients received baseline thyroid hormones (fT3, fT4 and TSH) tests and CT scan before radiotherapy. Repeated measures of the thyroid hormones and gland volume were performed at 3, 6, 12, 18, 24, 30, 36 and 48 months after treatment. Trend lines of the thyroid volume and hormone level changes against time were plotted. The incidence of hypothyroidism patients and its relationship with the dose were also evaluated. RESULTS: The mean thyroid volume followed a decreasing trend after radiotherapy, reaching a minimum (-39.8%) at 30 months and slightly increased afterward. The fT4 level followed a similar pattern with its mean value dropped by 21.5% at 30 months and became steady after 36 months. TSH level showed gradual rise from just after radiotherapy, reaching a peak at 24 months and became relatively steady after 36 months. The incidence of hypothyroidism increased to a maximum at 24 months (28.6%) and dropped afterwards. Thyroid Dmean and D50 were significantly correlated with hypothyroidism incidence in 12 to 30 months (ρ > 0.40, p < 0.05). CONCLUSION: The patterns of radiation induced thyroid volume shrinkage and fT4 level reduction were similar, with both of them showed decreasing trend from 0 to 30 months. The thyroid volume and function reached a relatively steady state after 36 months. The incidence of hypothyroidism increased up to 24 months and its frequency was associated with the thyroid dose.

Development of a normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism in nasopharyngeal carcinoma patients.

BACKGROUND: The objectives of this study were to build a normal tissue complication probability (NTCP) model of radiation-induced hypothyroidism (RHT) for nasopharyngeal carcinoma (NPC) patients and to compare it with other four published NTCP models to evaluate its efficacy. METHODS: Medical notes of 174 NPC patients after radiotherapy were reviewed. Biochemical hypothyroidism was defined as an elevated level of serum thyroid-stimulating hormone (TSH) value with a normal or decreased level of serum free thyroxine (fT4) after radiotherapy. Logistic regression with leave-one-out cross-validation was performed to establish the NTCP model. Model performance was evaluated and compared by the area under the receiver operating characteristic curve (AUC) in our NPC cohort. RESULTS: With a median follow-up of 24 months, 39 (22.4%) patients developed biochemical hypothyroidism. Gender, chemotherapy, the percentage thyroid volume receiving more than 50 Gy (V50), and the maximum dose of the pituitary (Pmax) were identified as the most predictive factors for RHT. A NTCP model based on these four parameters were developed. The model comparison was made in our NPC cohort and our NTCP model performed better in RHT prediction than the other four models. CONCLUSIONS: This study developed a four-variable NTCP model for biochemical hypothyroidism in NPC patients post-radiotherapy. Our NTCP model for RHT presents a high prediction capability. TRIAL REGISTRATION: This is a retrospective study without registration.