Correlation between morphological parameters and dosimetric parameters of the heart and spinal cord in the intermediate- and advanced-stage esophageal cancer.

BACKGROUND: Radiation therapy plays a pivotal role as the primary adjuvant treatment for esophageal cancer (EPC), emphasizing the critical importance of carefully balancing radiation doses to the target area and organs at risk in the radiotherapeutic management of esophageal cancer. AIMS: This study aimed to explore the correlation between morphological parameters and dosimetric parameters of the heart and spinal cord in intermediate- and advanced-stage esophagus cancer to provide a reference for clinical treatment. METHODS AND RESULTS: A total of 105 patients with intermediate- and advanced-stage EPC, who received treatment in our hospital from 2019 to 2021, were included. The morphological parameters were calculated by imaging. Intensity-modulated radiation therapy plan was executed at Raystation4.7. The PTV-G stood for the externally expanded planning target volume (PTV) of the gross tumor volume (GTV) and PTV-C for the externally expanded volume of the clinical target volume (CTV). The prescription dose of PTV-G and PTV-C was set as 60Gy/30F and 54Gy/30F, respectively. The linear regression model was used to analyze the correlation between morphologic parameters of EPC and dosimetric parameters of the heart and spinal cord. In 105 cases, the total lung length was correlated with the spinal cord maximum dose (D2 ). The heart mean doses (Dmean ) and heart V40 (the relative volume that receives 40 Gy or more) was correlated with PTV-G volume, PTV-G length; In middle- and upper-segment EPC cases, only the total lung volume was correlated with the spinal cord Dmean , spinal cord D2 , heart Dmean , and heart V40 ; In middle-stage EPC cases, the heart Dmean was correlated with the PTV-G volume, PTV-G length. The total lung length was correlated with the spinal cord D2 ; In middle- and lower-segment EPC, only the PTV-G volume and PTV-G length were correlated with the heart Dmean . All the aforementioned values were statistically significant. CONCLUSIONS: Combined with the unsegmented tumor and different locations, the organ at risk dose was comprehensively considered.

Correlation between hippocampal radiation doses and psychological condition for patients with stage T1-2 nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: The study aimed to investigate the correlation between radiation doses to the hippocampi and the psychological status of patients with stage T1-2 nasopharyngeal carcinoma (NPC) undergoing intensity modulated radiotherapy (IMRT) and recommend proper hippocampal dose limits for preserving patients' psychological well-being. MATERIALS AND METHODS: A retrospective study was conducted involving 152 newly diagnosed NPC patients. The patients' psychological status was assessed using the Hospital Anxiety and Depression Scale (HADS) before and after radiotherapy. The hippocampi were manually delineated on treatment planning images, and dosimetric parameters were obtained from dose-volume histograms. Logistic regression analysis was performed to identify influential dosimetric factors associated with anxiety and depression. RESULTS: The results showed that several dosimetric parameters to the hippocampi were significantly associated with anxiety but not depression. The optimal cut-off value for the independent predictor of anxiety was determined as D40 to hippocampi > 1500 cGy. Patients with D40 to hippocampi > 1500 cGy showed a higher probability for anxiety after radiotherapy. CONCLUSION: This study provides insights into the relationship between radiation doses to the hippocampi and the psychological status of stage T1-2 NPC patients undergoing IMRT. It suggests the importance of hippocampal protection for preserving patients' psychological well-being. Further studies are needed to validate these results.

Timing of radiotherapy in glioblastoma based on IMRT and STUPP chemo-radiation: may be no need to rush

To investigate the effect of surgery to radiotherapy interval (SRI) on the prognosis of patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma.MethodsRetrospective analysis of the relationship between SRI and prognosis of patients with IDH wild-type glioblastoma who received postoperative intensity modulated radiotherapy (IMRT) in our center from July 2013 to July 2019. The patients were divided into SRI ≤ 42 days (regular group) and SRI > 42 days (delay group). Kaplan–Meier univariate analysis and Cox proportional hazard model were used to analyze whether SRI was an independent factor influencing the prognosis.ResultsA total of 102 IDH wild-type glioblastoma were enrolled. Median follow-up was 35.9 months. The 1-, 2- and 3-year OS of “regular group” were 69.5%, 34.8%, 19.1%, and “delay group” were 69.8%, 26.1% and 13.4% respectively. Multivariate analysis showed that extent of resection (p = 0.041) was an independent prognostic factor for OS. SRI (p = 0.347), gender (p = 0.159), age (p = 0. 921), maximum diameter (p = 0.637) MGMT promoter methylation status (P = 0.630) and ki-67 expression (P = 0.974) had no effect on OS. Univariate analysis (p = 0.483) and multivariate analysis (p = 0.373) also showed that SRI had no effect on OS in glioblastoma who received gross total resection.ConclusionAppropriate extension in SRI has no negative effect on the OS of IDH wild-type glioblastoma. It is suggested that radiotherapy should be started after a good recovery from surgery. This conclusion needs further confirmed by long-term follow-up of a large sample. (AU)

Timing of radiotherapy in glioblastoma based on IMRT and STUPP chemo-radiation: may be no need to rush.

OBJECTIVE: To investigate the effect of surgery to radiotherapy interval (SRI) on the prognosis of patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma. METHODS: Retrospective analysis of the relationship between SRI and prognosis of patients with IDH wild-type glioblastoma who received postoperative intensity modulated radiotherapy (IMRT) in our center from July 2013 to July 2019. The patients were divided into SRI ≤ 42 days (regular group) and SRI > 42 days (delay group). Kaplan-Meier univariate analysis and Cox proportional hazard model were used to analyze whether SRI was an independent factor influencing the prognosis. RESULTS: A total of 102 IDH wild-type glioblastoma were enrolled. Median follow-up was 35.9 months. The 1-, 2- and 3-year OS of "regular group" were 69.5%, 34.8%, 19.1%, and "delay group" were 69.8%, 26.1% and 13.4% respectively. Multivariate analysis showed that extent of resection (p = 0.041) was an independent prognostic factor for OS. SRI (p = 0.347), gender (p = 0.159), age (p = 0. 921), maximum diameter (p = 0.637) MGMT promoter methylation status (P = 0.630) and ki-67 expression (P = 0.974) had no effect on OS. Univariate analysis (p = 0.483) and multivariate analysis (p = 0.373) also showed that SRI had no effect on OS in glioblastoma who received gross total resection. CONCLUSION: Appropriate extension in SRI has no negative effect on the OS of IDH wild-type glioblastoma. It is suggested that radiotherapy should be started after a good recovery from surgery. This conclusion needs further confirmed by long-term follow-up of a large sample.

Association between tumor morphology and dosimetric parameters of organs at risk after intensity-modulated radiotherapy in esophagus cancer.

PURPOSE: We explored the effects of geometrical topological properties of tumors such as tumor length and "axial cross-sectional area (ACSA)" of tumors (planning target volume [PTV] volume /PTV length) on the dosimetric parameters of organs at risk (lung and heart) in patients with esophagus cancer (EPC) treated by way of intensity-modulated radiation therapy (IMRT), so as to provide a guideline for the dosimetric limitation for organs at risk in IMRT treatment. METHODS: A retrospective analysis was done on 103 cases of patients with EPC who were treated by IMRT from November 2010 to August 2019, in which PTV-G stood for the externally expanded planning target volume (PTV) of the gross tumor volume (GTV) and PTV-C for the externally expanded volume of the clinical target volume (CTV). A linear regression model was employed to analyze the several pairs of correlation: the 1st one between the relative length of tumors (PTV length/lung length) and pulmonary dose-volume parameters, the 2nd one between ACSA of tumors and pulmonary dose-volume parameters, the 3rd one between PTV length and the dosimetric parameters of the heart, and the last one between ACSA of tumors and the dosimetric parameters of the heart. RESULTS: (i) There was a strong positive correlation between the relative length of tumors (PTV length/lung length) and V5 (p < 0.001, r = 0.73), and V10 (p < 0.001, r = 0.66) of the lung. There was a moderate positive correlation between the relative length of tumors and V30 (p < 0.001, r = 0.44) of the lung, and a weak positive correlation between the relative length of tumors and V20 (p < 0.001, r = 0.39) of the lung. (ii) There was a strong positive correlation between ACSA of tumors (PTV volume/PTV length) and V30 (p < 0.001, r = 0.67) of the lung, a moderate positive correlation between ACSA of tumors and V20 (p <0.001, r = 0.51) of the lung, and a weak positive correlation between ACSA of tumors and V10 (p = 0.019, r = 0.23) of the lung, yet there was not an obvious correlation between ACSA of tumors and V5 p > 0.05) of the lung. (iii) There was a moderate positive correlation between PTV length and V40 (p < 0.001, r = 0.58), and Dmean (p < 0.001, r = 0.52) of the heart, yet there was no obvious correlation between ACSA of tumors and Dmean and V40 of the heart (p > 0.05). CONCLUSIONS: (i) Compared with the high-dose region of the lung, the relative length of tumors (PTV length/lung length) has a greater impact on the low-dose region of the lung. The linear regression equation of scatter plot showed that when the relative length of tumors increased by 0.1, the lung dose-volume parameters of V5 , V10 , V20 , and V30 increased by approximately 5.37%, 3.59%, 1.05%, and 1.08%, respectively. When PTV length increased by 1 cm, Dmean and V40 of the heart increased by approximately 153.6 cGy and 2.03%, respectively. (ii) Compared with the low-dose region of the lung, the value of ACSA of tumors (PTV volume/PTV length) has a greater impact on the high-dose region of the lung. However, the value of ACSA of tumors has no significant effect on the dosimetric parameters of the heart (Dmean and V40 ). The linear regression equation of scatter plot showed that when ACSA of tumors increased by 10 cm2 , the lung dose-volume parameters of V10 , V20, and V30 increased by approximately 3.11%, 3.37%, and 4.01%, respectively.

Effect of tumor and normal lung volumes on the lung volume-dose parameters of IMRT in non-small-cell lung cancer.

OBJECTIVES: To explore the effect of tumor and normal lung volumes on lung volume-dose parameters in patients with non-small-cell lung cancer (NSCLC) who had undergone intensity-modulated radiation therapy (IMRT). METHODS: The clinical data of 208 patients with NSCLC who underwent radical IMRT between June 2014 and June 2018 were retrospectively analyzed. A regression model curve was used to evaluate the effect of tumor and normal lung volumes on normal lung relative volumes receiving greater than 5 and 20 Gy (V5, V20), on mean lung dose (MLD), and on absolute volumes spared from greater than 5 and 20 Gy (AVS5, AVS20). RESULTS: The V5, V20, and MLD of the bilateral lung were fitted to a quadratic equation curve with the change in tumor volume, which increased initially and then decreased when the tumor volume increased. The V5, V20, and MLD of the lung reached their apex when the tumor volumes were 288.07, 341.69, and 326.83 cm3, respectively. AVS5 and AVS20 decreased in a logarithmic curve with an increase in tumor volume. The V5, V20, and MLD of the small normal lung volume group were all significantly higher than those of the large normal lung volume group (p<0.001, p=0.004, p=0.002). However, the AVS5 and AVS20 of the small normal lung volume group were all significantly lower than those of the large normal lung volume group (p<0.001). CONCLUSION: The effects of tumor volume and normal lung volume on dose-volume parameters should be considered. AVS5 is an important supplementary dose limitation parameter for patients whose tumor volume exceeds a certain boundary value (approximately 300 cm3).

Effect of tumor and normal lung volumes on the lung volume-dose parameters of IMRT in non-small-cell lung cancer

OBJECTIVES: To explore the effect of tumor and normal lung volumes on lung volume-dose parameters in patients with non-small-cell lung cancer (NSCLC) who had undergone intensity-modulated radiation therapy (IMRT). METHODS: The clinical data of 208 patients with NSCLC who underwent radical IMRT between June 2014 and June 2018 were retrospectively analyzed. A regression model curve was used to evaluate the effect of tumor and normal lung volumes on normal lung relative volumes receiving greater than 5 and 20 Gy (V5, V20), on mean lung dose (MLD), and on absolute volumes spared from greater than 5 and 20 Gy (AVS5, AVS20). RESULTS: The V5, V20, and MLD of the bilateral lung were fitted to a quadratic equation curve with the change in tumor volume, which increased initially and then decreased when the tumor volume increased. The V5, V20, and MLD of the lung reached their apex when the tumor volumes were 288.07, 341.69, and 326.83 cm3, respectively. AVS5 and AVS20 decreased in a logarithmic curve with an increase in tumor volume. The V5, V20, and MLD of the small normal lung volume group were all significantly higher than those of the large normal lung volume group (p<0.001, p=0.004, p=0.002). However, the AVS5 and AVS20 of the small normal lung volume group were all significantly lower than those of the large normal lung volume group (p<0.001). CONCLUSION: The effects of tumor volume and normal lung volume on dose-volume parameters should be considered. AVS5 is an important supplementary dose limitation parameter for patients whose tumor volume exceeds a certain boundary value (approximately 300 cm3).

Prognostic Value of a Stemness Index-Associated Signature in Primary Lower-Grade Glioma.

OBJECTIVE: As a prevalent and infiltrative cancer type of the central nervous system, the prognosis of lower-grade glioma (LGG) in adults is highly heterogeneous. Recent evidence has demonstrated the prognostic value of the mRNA expression-based stemness index (mRNAsi) in LGG. Our aim was to develop a stemness index-based signature (SI-signature) for risk stratification and survival prediction. METHODS: Differentially expressed genes (DEGs) between LGG in the Cancer Genome Atlas (TCGA) and normal brain tissue samples from the Genotype-Tissue Expression (GTEx) project were screened out, and the weighted gene correlation network analysis (WGCNA) was employed to identify the mRNAsi-related gene sets. Meanwhile, the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed for the functional annotation of the key genes. ESTIMATE was used to calculate tumor purity for acquiring the correct mRNAsi. Differences in overall survival (OS) between the high and low mRNAsi (corrected mRNAsi) groups were compared using the Kaplan Meier analysis. By combining the Lasso regression with univariate and multivariate Cox regression, the SI-signature was constructed and validated using the Chinese Glioma Genome Atlas (CGGA). RESULTS: There was a significant difference in OS between the high and low mRNAsi groups, which was also observed in the two corrected mRNAsi groups. Based on threshold limits, 86 DEGs were most significantly associated with mRNAsi via WGCNA. Seven genes (ADAP2, ALOX5AP, APOBEC3C, FCGRT, GNG5, LRRC25, and SP100) were selected to establish a risk signature for primary LGG. The ROC curves showed a fair performance in survival prediction in both the TCGA and the CGGA validation cohorts. Univariate and multivariate Cox regression revealed that the risk group was an independent prognostic factor in primary LGG. The nomogram was developed based on clinical parameters integrated with the risk signature, and its accuracy for predicting 3- and 5-years survival was assessed by the concordance index, the area under the curve of the time-dependent receiver operating characteristics curve, and calibration curves. CONCLUSION: The SI-signature with seven genes could serve as an independent predictor, and suggests the importance of stemness features in risk stratification and survival prediction in primary LGG.

[Effect of tumor volume on pulmonary dose-volume parameter by intensity-modulated radiation therapy in non-small cell lung cancer].

OBJECTIVE: To explore the effectof tumor volume on pulmonary dose-volume parameters by intensity-modulated radiation therapy (IMRT) in non-small cell lung cancer (NSCLC), and to provide a basis for pulmonary dose parameters in IMRT treatment.
 Methods: A total of 204 patients with NSCLC received IMRT were retrospectively analyzed from June, 2009 to October, 2013. The prescribed dose of planning target volume (PTV) for primary tumor was 60-66Gy (2.00-2.25 Gy, 27-33 times in all). The fractional volume percent of the lung received a dose >5 or 20 Gy (V5, V20), and absolute volume of lung received a dose <5 Gy (AVS5).The mean lung dose (MLD) in normal tissues were analyzed. Regression model curve was used to analyze them along with the change of primary tumor volume.
 Results: With the increase in lung tumor volume, the V5, V20 and MLD presented quadratic equation curve, and AVS5 presented logarithmic equation. When the tumor volume, less than a certain value (294.6, 283.2, 304.9 cm3, respectively), the V5, V20 and MLD increased with tumor size and presented an increased quadratic curve; when the tumor volume was higher than a certain value (294.6, 283.2, 304.9 cm3 respectively), the V5, V20 and MLD was declined. The AVS5 was declined in a logarithmic curve along with the increase of tumor volume.
 Conclusion: With the increase in lung tumor volume, the change in rule of V5, V20, MLD and AVS5 is not completely equivalent. When the tumor volume exceeds a certain boundary value (about 300 cubic centimeter), the corresponding tumor diameter is about 7-8 cm. In addition to the focus on pulmonary V5, V20 and MLD, we should also pay more attention to AVS5 restrictions in establishment of IMRT in NSCLC.

Association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury after intensity-modulated radiotherapy in lung cancer: a retrospective analysis.

The aim of this study was to investigate the association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury (RILI) after intensity-modulated radiotherapy (IMRT) for lung cancer. The normal lung relative volumes receiving greater than 5, 10, 20 and 30 Gy (V5-30) mean lung dose (MLD), and absolute volumes spared from greater than 5, 10, 20 and 30 Gy (AVS5-30) for the bilateral and ipsilateral lungs of 83 patients were recorded. Any association of clinical factors and dose-volume parameters with Grade ≥2 RILI was analyzed. The median follow-up was 12.3 months; 18 (21.7%) cases of Grade 2 RILI, seven (8.4%) of Grade 3 and two (2.4%) of Grade 4 were observed. Univariate analysis revealed the located lobe of the primary tumor. V5, V10, V20, MLD of the ipsilateral lung, V5, V10, V20, V30 and MLD of the bilateral lung, and AVS5 and AVS10 of the ipsilateral lung were associated with Grade ≥2 RILI (P < 0.05). Multivariate analysis indicated AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI (P = 0.010, OR = 0.272, 95% CI: 0.102-0.729). Receiver operating characteristic curves indicated Grade ≥2 RILI could be predicted using AVS5 of the ipsilateral lung (area under curve, 0.668; cutoff value, 564.9 cm(3); sensitivity, 60.7%; specificity, 70.4%). The incidence of Grade ≥2 RILI was significantly lower with AVS5 of the ipsilateral lung ≥564.9 cm(3) than with AVS5 < 564.9 cm(3) (P = 0.008). Low-dose irradiation relative volumes and MLD of the bilateral or ipsilateral lung were associated with Grade ≥2 RILI, and AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI for lung cancer after IMRT.