ABSTRACT
Objective To investigate the effect of couch rotation angle on non-coplanar static intensity-modulated radiotherapy (IMRT) plan for gastric cancer and to provide a reference for clinical planning. Methods A retrospective analysis was conducted on patients who recently underwent postoperative IMRT for gastric cancer. Twenty patients who received radiotherapy in the centre of Radiation Oncology of Huanggang Central Hospital from August 2022 to January 2023 were selected. That were selected to receive a seven-field coplanar static IMRT plan based on a couch rotation angle of 0° as the control group. Then, based on the coplanar IMRT plan, only the couch rotation angle of gantry angles 30° and 330° was changed to 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80°, and 90°, respectively, and nine different non-coplanar plans were established. The homogeneity index (HI), conformity index (CI) of the target volume, and monitor unit (MU), as well as Dmean, V20, and V30 of the left and right kidneys, Dmax, Dmean, V10, V20, and V30 of the spinal cord, and Dmax, Dmean, V10, V20, V30, and V40 of the small intestine and liver were compared among the 10 plans. The MU and the dosimetric parameters of the target volumes and When the couch rotation angle was 60°, the minimum HI and maximum CI of the target volume were 0.0714±0.0089 and 0.9271±0.0108, respectively, and the minimum MU was 438±26, with the best homogeneity and conformity in the target volume and the shortest machine treatment time (P＜0.05). When the couch rotation angle was 10°, the Dmax of the small intestine was lowest, being (4620.73±99.27) cGy. When the couch rotation angle was 60°, the Dmean of the left and right kidneys was lowest, being (1246.30±130.35) cGy and (1001.52±103.33) cGy, respectively; the V20 of the left and right kidneys was lowest, being 22.87±6.29 and 19.69±1.84, respectively; the V10 and V30 of the spinal cord were lowest, being 40.08±4.92 and 1.68±0.34, respectively (P＜0.05). Conclusion The couch rotation angle has some influence on the postoperative treatment planning for patients with gastric cancer. In the design of non-coplanar plan for gastric cancer, the couch rotation angle of 60° contributes to establishing a better radiotherapy plan.
ABSTRACT
Objective To evaluate the clinical efficacy and safety of simultaneous enhanced accelerated radiation therapy for brain metastases (SMART-Brain) combined with functional area protection. Methods SMART-Brain was planned for 60 patients with multiple brain metastases. Using the whole brain intensity modulation technique, important functional areas such as hippocampus were protected against irradiation by delivering a dose of 30 Gy in 10 fractions. Meanwhile, a high dose of 40 Gy was delivered to brain metastases in 10 fractions. All patients were followed up to evaluate the efficacy, incidence of adverse reactions, median overall survival (OS), and intracranial progression-free survival (IPFS). Results The effective rate was 73.33% (44 cases), the disease control rate was 91.67% (55 cases), median OS was 15.2 months, and IPFS was 12 months. The 1 and 2-year OS was 66.7% and 26.4%, and the 1-year IPFS was 46.7%. The MMSE scores at 1, 3, and 6 months after SMART showed no significant differences compared with baseline scores (P > 0.05). Grade 2 and above inner ear damage such as otitis media, hearing loss, and dizziness was absent. Conclusion Smart-Brain can significantly reduce the treatment time and better protect the organs at risk, and serves as an economical, safe, and effective radiotherapy regimen in areas with limited technical conditions.
ABSTRACT
Objective To evaluate the effects of the modified opration of benign tumor in parotid gland on the prevention of Frey syndrome.Methods the Parotid benign tumor resection in 28 cases were selected,according to the different treatment methods were divided into observation group of 12 cases,16 cases of the control group.The modified surgical patients in the observation group,two flap method,preservation,preservation of parotid masseter fascia in the branches of the great auricular nerve and parotid region resection,the control group was treated by routine tumors of the parotid gland and parotid superficial lobectomy or resection.Patients were followed up for 6 months to 1 years,underwent minor test,the incidence of Frey syndrome in 2 cases were recorded,postoperative incidence of Frey syndrome were compared.Results The incidence of Frey syndrome in the observation group was significantly reduced compared with the control group.The difference was statistically significant (χ2 =7.479,P <0.05 ). Conclusion The effects of modified opetation combined with secondry disc method in benign tumor of parotid gland on the prevention of Frey syndrome has obvious advantages comparing with the control.