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Radiotherapy is a pivotal method in cancer treatment harbouring immunomodulatory effects. Radiotherapy combined with immunotherapy has been proven to yield promising preliminary results in certain types of tumors. Most studies have concentrated on the dose fractionation of radiotherapy and timing of radiotherapy and immunotherapy. With the development of related studies, attention has been gradually paid to the influence of target volume upon circulating lymphocytes and tumor microenvironment. The interaction between target volume and immunotherapy has been valued. For tumors not suitable for hypofractionated radiotherapy, such as advanced esophageal cancer, conventional fractionated radiotherapy has been adopted. The volume and planning of target volume play a pivotal role in radiotherapy combined with immunotherapy. This article illustrates the feasibility of radiotherapy combined with immunotherapy, theory and conception of optimizing target volume.
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Objective:To explore the feasibility of low-dose 4DCT scanning in simulation and target delineation for solitary pulmonary tumors (SPTs).Methods:23 patients with SPTs received 4DCT scanning simulation with the conventional scanning (CON), low voltage (LV), low current (LA) and low voltage combined with low current (LVA) in sequence. Based on the 4DCT images derived from the four sets of scanning parameters, the internal gross tumor volume (IGTV CON, IGTV V, IGTV A, IGTV VA) of SPTs were delineated and matched. Taking IGTV CON as reference, the tumor displacement and the centroid position of IGTV V, IGTV A and IGTV VA were compared with IGTV CON. The radiation doses under different scanning parameters were compared. Results:The volumes of IGTV CON, IGTV V and IGTV A were (12.26±12.30) cm 3, (12.21±12.16) cm 3 and (11.87±11.70) cm 3, respectively ( P=0.337). IGTV VA was (11.34±11.07) cm 3, significantly smaller than IGTV CON ( P=0.005). There was no significant difference in the centroid positions of IGTV CON, IGTV V, IGTV A and IGTV VA in three directions ( P=0.491, 0.360, 0.136). The Dice′s similarity coefficient (DSC VA) was significantly lower than DSC V and DSC A ( P=0.004, 0.030). The tumor displacement measured by the four sets of 4DCT images was similar in the LR direction ( P=0.470), and also in the AP direction ( P=0.108). For the displacement in the SI direction, LVA scanning was smaller than CON ( P=0.015). The radiation doses under four different scanning conditions were (397.0±140.3) mGy·cm, (175.0±61.8) mGy·cm, (264.8±95.3) mGy·cm and (116.8±41.2) mGy·cm, respectively ( P<0.001). Conclusions:LV or LA scanning exert no significant effect on the volume, centroid position of IGTV and the tumor displacement in 4DCT simulation for SPTs. The radiation dose that patients receive under LV and LV scanning is lower than that of CON. Consequently, LV or LA scanning is feasible in 4DCT simulation and target delineation for SPTs.
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Objective:To systematically compare the efficacy and safety of chrono-chemotherapy combined with radiotherapy in patients with locally advanced nasopharyngeal carcinoma.Methods:Seven databases were searched, including the Cochrane Library (Issue 5, 2021), PubMed, Embase, CBM, CNKI, VIP and Wanfang Database. The method ological quality of the eligible studies was evaluated. The Meta-analysis was performed by the Revman 5.3 software.Results:Sixteen studies consisting of 1275 patients were finally included. Among them, 642 patients were treated with chrono-chemotherapy combined with radiotherapy and 633 patients received conventional chemotherapy combined with radiotherapy. Results showed that compared with conventional chemotherapy group, the effective rate was significantly elevated ( OR=1.66, 95% CI: 1.17-2.34, P=0.004), the incidence of leucopenia, thrombocytopenia, gastrointestinal reaction, grade 3-4 oral mucosal reaction and grade 3-4 radiothermitis was significantly reduced (all P<0.001), and the quantity of CD3, CD4 and CD4/CD8 was significantly increased in the chrono-chemotherapy group. Conclusion:Current evidence shows that compared with conventional chemotherapy, chrono-chemotherapy combined with radiotherapy could improve the effective rate, reduce adverse reactions and mitigate the destruction of immune function simultaneously.
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Objective:To investigate the post-traumatic growth status of tumor patients receiving radiotherapy and analyze its influencing factors, aiming to provide theoretical basis for clinical doctors and nurses to formulate targeted intervention strategies.Methods:A cross-sectional survey of 170 tumor patients receiving radiotherapy admitted to Department of Radiotherapy of Sun Yat-sen Memorial Hospital was conducted by convenience sampling method, general information questionnaire and a post-traumatic growth inventory (PTGI).Results:The average PTGI score of 170 patients was 83.11±16.74, and 141 cases of them had significant post-traumatic growth, accounting for 82.9%(score ≥71). Logistic regression analysis showed that personality type, work status, and the times of hospitalization were the influencing factors of post-traumatic growth (all P<0.05). Conclusions:Tumor patients undergoing radiotherapy obtain a high level of post-traumatic growth. Medical staff should make full use of the patients’ potential for post-traumatic growth and implement interventions as soon as possible to promote the physical and mental health of tumor patients undergoing radiotherapy.
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Objective:To evaluate the prognostic factors and the value of definitive pelvic radiotherapy in patients with stage Ⅳ B hematogenous metastatic cervical squamous cell carcinoma. Methods:Clinical data of 80 patients with Ⅳ B stage squamous cell carcinoma admitted to Zhejiang Cancer Hospital from 2006 to 2016 were retrospectively analyzed. The survival analysis was conducted by Kaplan- Meier method. Prognostic factors were analyzed by Cox models. Results:The 1-, 2-and 5-year overall survival (OS) and progression-free survival (PFS) rates were 52.5%, 26.3%, 16.8% and 25%, 13.8%, 8.8%, with a median OS of 13.8 months and a median PFS of 5.6 months, respectively. The most common site of metastasis was bone (51.3%), followed by lung (36.3%) and liver (26.3%). Univariate analysis revealed that chemotherapy combined with definitive pelvic radiotherapy and ≥6 cycles of chemotherapy were positively correlated with OS and PFS, whereas ECOG performance status score of 3-4 and liver metastasis were negatively correlated with OS and PFS. In multivariate analysis, liver metastasis ( HR=2.23, 95% CI: 1.01-4.91, P=0.048) and ECOG performance status score of 3-4( HR=2.01, 95% CI: 1.03-3.91, P=0 0.040) were significantly correlated with poor OS. Subgroup multivariate analysis showed that compared with chemotherapy±palliative radiotherapy, systemic chemotherapy combined with definitive pelvic radiotherapy significantly improved OS ( HR=0.39, 95% CI: 0.18-0.84, P=0.016). Compared with double drugs combined with<4 cycles of chemotherapy, double drugs in combination with ≥4 cycles of chemotherapy significantly improved OS ( HR=0.32, 95% CI: 0.15-0.68, P=0.003). Conclusions:Patients with low ECOG performance status score or liver metastasis obtain poor prognosis. Definitive pelvic radiotherapy combined with chemotherapy can enhance clinical prognosis of patients with Ⅳ B stage hematogenous metastatic cervical squamous cell carcinoma.
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Objective:To assess the role of Glasgow prognostic score (GPS) in the prognostic evaluation of nasopharyngeal carcinoma patients.Methods:Clinical data of 129 nasopharyngeal carcinoma patients who received radical radiotherapy in Affiliated Hospital of Jiangnan University from January 2012 to December 2013 were retrospectively analyzed. Clinicopathological characteristics of the patients were collected, including gender, age, TNM staging, pathological type and treatment regimen, etc. The GPS before and at 3 months after radiotherapy were calculated. The survival curve was drawn by the Kaplan- Meier method. Cox regression model was used for analysis of prognostic factors. The area under the receiver operating characteristic (ROC) curve (AUC) was utilized to evaluate the predictive capability of clinical parameters on prognosis. Results:With a median follow-up of 89.0 months (range: 5.1-104.6 months), the 5-year progression-free survival (PFS) of 129 patients was 79.8% and 84.5% for the 5-year overall survival (OS). At 3 months after radiotherapy, the 5-year PFS were 85.6%, 61.1% and 33.3% in the GPS 0, 1 and 2 groups, and 90.4%, 66.7% and 33.3% for the 5-year OS, respectively (all P<0.01). At 3 months after radiotherapy, the GPS, clinical staging (Ⅰ-Ⅲ vs. Ⅳ A) and concurrent chemotherapy were significantly correlated with PFS and OS (all P<0.01). ROC curve showed that at 3 months after radiotherapy, the AUC values of GPS, clinical staging and two combined in predicting OS were 0.694, 0.815 and 0.860, respectively. Conclusions:At 3 months after radiotherapy, higher GPS is an independent poor prognostic factor for nasopharyngeal carcinoma patients. The combination of GPS and clinical staging yields high accuracy in the prognostic evaluation of nasopharyngeal carcinoma patients.
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Objective:To compare the differences of postoperative clinical target volume of internal mammary lymph node (CTV ImlN) by different delineation methods, and to explore the reasonable method of CTV ImlN delineation after internal mammary lymph node dissection (ImlND). Methods:A total of 20 breast cancer patients who had undergone modified radical mastectomy (MRM) with ImlND on the affected side and had complete preoperative and postoperative CT images were selected. The CTV (CTV pr-I, CTV pr-a) of both sides of ImlN were delineated on preoperative CT images according to RTOG guideline. On postoperative CT images, three different methods including deformation image registration (DIR) method, visual contrast method and precise measurement method, were employed to delineate the postoperative CTV ImlN of the affected side. The targets were named as CTV DIR, CTV V and CTV M, respectively. The central displacement, target volume, degree of inclusion (DI) and conformity index (CI) of CTV pr-a, CTV V, CTV M and CTV DIR were compared. Results:The central displacement of CTV V, CTV M and CTV DIR from CTV pr-a was 2.17 cm, 1.44 cm and 1.25 cm, respectively. The target volume of CTV pr-a, CTV pr-I, CTV V, CTV M and CTV DIR was 2.10 cm 3, 2.17 cm 3, 2.04 cm 3, 1.88 cm 3 and 2.07 cm 3 respectively. There was no significant difference in the target volume (all P>0.05). The CI values of CTV V-CTV pr-a and CTV M-CTV pr-a were both 0.16, and that of CTV DIR-CTV pr-a was 0.43. The CI value of CTV DIR was significantly higher than those of CTV V and CTV M (both P<0.01). The DI values of CTV V-CTV pr-a, CTV M-CTV pr-a and CTV DIR-CTV pr-a were 0.26, 0.24 and 0.58, respectively. The DI value of CTV DIR was significantly higher than those of CTV V and CTV M (both P<0.01). Conclusions:It is difficult to accurately delineate the CTV ImlN for patients after ImlND. However, the spatial position fitness of the target region delineated by DIR method is better than those by visual contrast and precise measurement methods.
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Magnetic resonance imaging (MRI) is a technology with no radiation and high resolution of soft tissues. Therefore, MRI-guided radiotherapy has become a hot spot in the field of radiotherapy. It is of great importance to accurately delineate the targets in radiation oncology. Currently, the delineation of targets is mostly completed by manual segmentation, which is time-consuming, subjective and inconsistent. Automatic segmentation can improve the efficiency and consistency without sacrificing the accuracy of segmentation. In this article, the automatic segmentation methods of MRI applied in radiotherapy were reviewed. The goals, challenges and methods of automatic segmentation for different radiotherapy sites including prostate, nasopharyngeal carcinoma, brain tumors and other organs were analyzed and discussed.
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Objective:To explore the application value of skin lead marker combined with iSCOUT image-guided positioning system in monitoring and correcting the setup error of intensity-modulated radiotherapy (IMRT) for breast cancer and calculate the PTV margin, aiming to provide reference for clinical practice.Methods:25 breast cancer patients treated with IMRT after modified radical mastectomy in Fujian Medical University Union Hospital from April to August 2019 were enrolled in this study. The skin lead marker combined with iSCOUT image-guided positioning system was employed for image-guided positioning based on the gold standard registration algorithm. Initial setup errors on the x (lateral), y (craniocaudal) and z (anteroposterior) axis and residual errors after the position correction were recorded and analyzed. The effect of the errors before and after image-guided correction upon the plan dose was compared and the reasonable PTV margin was calculated.Results:25 patients received 150 times of positioning verification using skin lead marker combined with iSCOUT image-guided positioning system. The absolute residual errors on the x-, y-and z-axis were (1.53±0.96), (1.30±0.99) and (1.34±0.92) mm, significantly smaller than the initial setup errors of (2.63±2.12), (2.41±2.45) and (3.07±2.77) mm (all P<0.001). The percentage of dose deviation due to residual errors was also smaller than that of the initial errors. Significant differences were observed in D 98%, D 2%, D max of PTV, D max of the heart, D max of the healthy breast, and D mean of the affected lung and both lungs. The percentage deviation from the original plan was decreased from 2.18%, 3.19%, 10.66%, 8.75%, 48.21%, 10.50%, and 3.66% to 0.38%, 0.23%, 2.31%, 0.04%, 13.78%, 6.35% and 0.41%, respectively (all P<0.05). PTV margins on the x-, y-and z-axis after correction were calculated as 1.87, 1.75 and 1.69 mm, respectively. Conclusion:It is feasible and valuable to apply the skin lead marker combined with iSCOUT image-guided positioning system in the positioning verification and correction of breast cancer radiotherapy position, providing novel reference for clinical PTV margin.
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Programmed cell death-1/programmed cell death-ligand 1(PD-1/PD-L1) inhibitors have been approved for a variety of tumors, whereas the efficacy as monotherapy is low. How to sensitize the efficacy of PD-1/PD-L1 inhibitors through combined radiotherapy is the current research focus. Multiple studies have demonstrated that the combination of radiotherapy and anti-PD-1/PD-L1 therapy has yielded survival benefits. Nevertheless, ionizing radiation is a double-edged sword for anti-PD-1/PD-L1 therapy. For patients with metastatic cancers, radiotherapy should be fully exerted as a sensitizer to systemic anti-PD-1/PD-L1 therapy and the immunosuppressive effects should be avoided as much as possible. It is closely correlated with the selection of radiation dose, fraction size, treatment timing and irradiated numbers and sites. Therefore, this article reviews how to optimize radiotherapy combined with anti-PD-1/PD-L1 treatment scheduled for advanced stage metastatic cancers.
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From synchronous metastasis to metachronous metastasis and from oligometastasis to disseminated metastasis, distant metastatic nasopharyngeal carcinoma (stage IV B) has great heterogeneity. The prognosis of stage IV B nasopharyngeal carcinoma patients with distant metastases is closely related to the anatomical characteristics of metastases. Therefore, it is necessary to subdivide M 1 stage to lay the foundation for individualized treatment of patients with metastatic nasopharyngeal carcinoma. In addition to systemic chemotherapy, the primary tumors and metastatic lesions should be considered during the treatment of newly-diagnosed metastatic nasopharyngeal carcinoma. Currently, there is a lack of recognized treatment modes for newly-diagnosed stageⅣ B nasopharyngeal carcinoma, and more studies are needed to evaluate the clinical benefits of different treatment methods.
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Radiotherapy (RT) is one of the three prevailing therapeutics for tumors. With rapid development of immunotherapy (IM), the combination of IM and RT has gainned increasingly widespread attention. Cytotoxic T lymphocyte associated protein-4(CTLA-4) inhibitor is an important checkpoint target in immune activation and regulation, which exerts significant anti-tumor effects in melanoma and non-small cell lung cancer, etc. Accordingly, the combination of RT and anti-CTLA-4 antibody has become a hot spot. This article reviews research progress on pre-clinical and clinical evidences of RT combined with anti-CTLA-4 antibody, which provides evidence for further exploration in this field.
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Objective:To evaluate the effect of prophylactic irradiation of internal mammary lymph nodes in patients with breast cancer in this Meta-analysis.Methods:CNKI, Wanfang Medical network, CBM, PubMed, EMBASE and Web of Science were searched by computer. The controlled clinical studies comparing whether or not internal mammary lymph node irradiation as an intervention were included and the quality of the included literature was evaluated according to Newcastle-Ottawa Scale (NOS). RevMan 5.3 software and Stata 14 software were used for Meta-analysis.Results:A total of 11 original articles were included, and 13 181 patients were included for Meta-analysis. There was no statistically significant difference in the overall survival (OS) between patients with and without internal mammary lymph node irradiation ( P=0.490). The subgroup analysis using the date of treatment and the degree of risk in the enrolled population as criteria showed that 5-year OS was significantly increased after internal mammary area irradiation in high-risk stage Ⅱ-Ⅲ patients (N+ , T 3-T 4 stage) with the date of treatment of after 2000( P=0.003, 0.006). Compared with patients without internal mammary area irradiation, internal mammary irradiation significantly increased the 5-year disease-free survival (DFS)( P<0.001). Conclusion:Under the modern radiotherapy technology, internal mammary lymph node irradiation improves the DFS of patients, and may bring OS benefits to high-risk stage Ⅱ-Ⅲ breast cancer patients (N+ , T 3-T 4 stage).
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Objective:To investigate the radiation field and dose selection of patients with isolated chest wall recurrence (ICWR) after modified radical mastectomy, and analyze the prognostic factors related to subsequent chest wall recurrence.Methods:Clinical data of 201 patients with ICWR after mastectomy admitted to the Fifth Medical Center, Chinese PLA General Hospital from 1998 to 2018 were retrospectively analyzed. None of the patients received postoperative adjuvant radiotherapy. After ICWR, 48 patients (73.6%) underwent surgery and 155 patients (77.1%) received radiotherapy. Kaplan-Meier method was used to calculate the post-recurrence progression-free survival (PFS) rates and the difference was compared by log-rank test. Multivariate analysis was performed using Cox regression model. Competing risk model was adopted to estimate the subsequent local recurrence (sLR) rates after ICWR and the difference was compared with Gray test. Multivariate analysis was conducted using F&G analysis. Results:With a median follow up of 92.8 months after ICWR, the 5-year PFS rate was 23.2%, and the 5-year sLR rate was 35.7%. Multivariate analysis showed that patients with surgery plus radiotherapy and recurrence interval o F>12 months had a lower sLR rate. Patients with recurrence interval o F>48 months, local plus systemic treatment and surgery plus radiotherapy had a higher PFS rate. Among the 155 patients who received chest wall radiotherapy after ICWR, total chest wall irradiation plus local boost could improve the 5-year PFS rate compared with total chest wall irradiation alone (34.0% vs. 15.4%, P=0.004). Chest wall radiation dose (≤60 Gy vs.>60 Gy) exerted no significant effect upon the sLR and PFS rates (both P>0.05). In the 53 patients without surgery, the 5-year PFS rates were 9.1% and 20.5%( P=0.061) with tumor bed dose ≤60 Gy and>60 Gy, respectively. Conclusions:Local radiotherapy is recommended for patients with ICWR after modified radical mastectomy of breast cancer, including total chest wall radiation plus local boost. The radiation dose for recurrence should be increased to 60 Gy, and it should be above 60 Gy for those who have not undergone surgical resection. In addition, patients with ICWR still have a high risk of sLR, and more effective treatments need to be explored.
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Objective:To evaluate the application value of deep deconvolutional neural network (DDNN) model for automatic segmentation of target volume and organs at risk (OARs) in patients with nasopharngeal carcinoma (NPC).Methods:Based on the CT images of 800 NPC patients, an end-to-end automatic segmentation model was established based on DDNN algorithm. Ten newly diagnosed with NPC were allocated into the test set. Using this DDNN model, 10 junior physicians contoured the region of interest (ROI) on 10 patients by using both manual contour (MC) and DDNN deep learning-assisted contour (DLAC) methods independently. The accuracy of ROI contouring was evaluated by using the DICE coefficient and mean distance to agreement (MDTA). The coefficient of variation (CV) and standard distance deviation (SDD) were rendered to measure the inter-observer variability or consistency. The time consumed for each of the two contouring methods was also compared.Results:DICE values of gross target volume (GTV) and clinical target volume (CTV), MDTA of GTV and CTV by using DLAC were 0.67±0.15 and 0.841±0.032, (0.315±0.23) mm and (0.032±0.098) mm, respectively, which were significantly better than those in the MC group (all P<0.001). Except for the spinal cord, lens and mandible, DLAC improved the DICE values of the other OARs, in which mandible had the highest DICE value and optic chiasm had the lowest DICE value. Compared with the MC group, GTV, CTV, CV and SDD of OAR were significantly reduced (all P<0.001), and the total contouring time was significantly shortened by 63.7% in the DLAC group ( P<0.001). Conclusion:Compared with MC, DLAC is a promising method to obtain superior accuracy, consistency, and efficiency for the GTV, CTV and OAR in NPC patients.
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In recent years, increasing evidence has shown that hyperthermia is safe, effective and causes low toxicity. Hyperthermia can exert synergistic effect with other treatments, such as radiotherapy and chemotherapy. It has become an important adjuvant anti-tumor treatment secondary to surgery, chemotherapy, radiotherapy and biological treatment. Hyperthermia can improve the efficacy of radiotherapy and chemotherapy by directly inhibiting tumor cells and heat-induced radiosensitizing effect. Hence, hyperthermia is gradually applied in the multimodality treatment of tumors. In this article, we intend to review the research progress on the application of tumor hyperthermia in conventional radiotherapy, chemotherapy, immunotherapy and new biomaterials.
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Lymphocyte-led immunity plays an important role in the occurrence and development of tumors. It has been found that radiotherapy can induce lymphopenia in patients with solid tumors, and radiotherapy-induced lymphopenia (RIL) might be caused by the irradiation of circulating blood. The sensitivity to irradiation differs among different subtypes of lymphocytes. RIL can be affected by radiation fractionation, technique and volume. Meanwhile, it has been proven that RIL can significantly reduce the survival of patients with multiple solid tumors. In this article, relevant researches were reviewed, aiming to advance clinical treatment decisions and optimize radiotherapy protocols.
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Surgical resection is the main radical treatment of early and mid-stage primary liver cancer (PLC), but the high postoperative recurrence rate is the main factor affecting the curative effect. With recent advancement in techniques, the efficacy and safety of radiation therapy for PLC have been widely proven. In this review, we will investigate the combination of surgery and radiation therapy, covering the topics of preoperative or postoperative radiotherapy for PLC with portal vein tumor thrombus, postoperative adjuvant radiotherapy in PLC with narrow surgical margin or microvascular invasion, stereotactic body radiation therapy as a bridge to liver transplantation, radiotherapy in conversion to resectability for intrahepatic inoperable PLC. Despite radiation therapy is one of the effective therapeutic options for PLC, there is still a compelling need for prospective, randomized, controlled phase Ⅲ trials to acquire high-levelclinical evidence for confirming the role of radiation therapy in the treatment of PLC.
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Objective:To explore the value of BLADE sequence in determining the target range of esophageal cancer radiotherapy through the correlation and consistency between measured esophageal cancer length on the MRI-BLADE sequence and the surgical pathological specimens.Methods:Clinical data of 36 patients who were pathologically diagnosed with esophageal carcinoma and received preoperative esophageal MRI in the Affiliated Cancer Hospital of Zhengzhou University between January 2016 to June 2019 were collected. The CT, DWI and BLADE sequence images of all participants were collected and imported into the Monaco system, by which the correlation and consistency between the tumor length measured based on these three imaging methods were statistically compared. Furthermore, the differences in gross tumor volume (GTV) delineated by different physicians in different images were compared.Results:The correlation coefficients of the tumor length measured by CT, DWI and BLADE and pathological specimen length were 0.467, 0.723 and 0.896, respectively. The consistency analysis indicated that all the differences between the BLADE sequence and pathological specimen length were within the 95% consistency limit. The consistency and correlation between the BLADE sequence and actual tumor length were significantly better than those between the DWI sequence and CT images (both P<0.05). The volume of DWI and BLADE images obtained by four physicians was significantly smaller than that of CT images (both P<0.05). The differences in GTV delineated by different physicians by these three imaging methods were insignificant (all P>0.05), but the GTV delineated by the four physicians on the BLADE sequence were more similar (all P>0.05). Conclusions:BLADE sequence can help physicians to determine the upper and lower boundaries of esophageal tumors more accurately and reduce the differences in GTV delineation among different physicians. And it can effectively improve the unity of individual′s understanding of the scope of target area delineation, and improve the objectivity of clinicians′ judgment of GTV. BLADE sequence can be used as an important imaging tool for accurate target delineation in radiotherapy.
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Objective:To investigate the correlation between the changes of oral bacterial flora during head and neck radiotherapy and radiation-induced oral mucositis (ROM).Methods:The oral bacterial samples of patients with nasopharyngeal carcinoma and accompanying family members were obtained before and at the end of radiotherapy and subjected to high-throughput sequencing. C57BL/6 mice were used to establish the ROM models. On the 9 th day after radiotherapy, oral bacterial samples were collected in the radiotherapy group and the negative control group. On the 3 rd, 5 th, 7 th, and 9 th days post-radiotherapy, the tongue tissues were obtained from another batch of mice in the negative control and radiotherapy groups. Inflammatory factors were detected with PCR and HE staining was performed. Results:The oral bacterial diversity of patients after radiotherapy significantly differed from that of patients before radiotherapy and their accompanying family members before and after radiotherapy in Observed species, Chao1, Simpson index (all P<0.05). There was a significant difference in Shannon index between the severe and mild ROM patients ( P=0.036). LEfSe analysis showed that patients with severe ROM had higher levels of g_ Streptococcus and f_ Streptococcus, and lower levels of f_ Familyxl, g_ Gemini and o_ Bacillus. The Simpson index and PCoA results in the oral bacterial samples significantly differed between the negative control and radiotherapy groups (all P<0.05). Conclusions:Radiotherapy can disrupt the balance of bacterial flora. The dysregulated oral bacterial flora is closely associated with the aggravation of ROM.