Mathematical evaluation of post-radiotherapy salivary gland function using salivary gland scintigraphy

Objective: Xerostomia is the most common treatment-related toxicity after radiotherapy (RT) for head and neck carcinoma, reducing the quality of life of patients due to a decrease in salivary gland function. Methods: Salivary gland scintigraphy was performed to quantitatively evaluate the salivary gland functions in patients undergoing RT. It was done chronologically for 62 salivary glands of 31 patients before RT and retested 12 months later. Results: The salivary gland functions of most patients deteriorated post-RT and recovered when the radiation dose to the salivary gland was not high. The mean dose to the salivary gland was found to be the most reliable factor in deteriorating salivary gland function, and the tolerance dose was determined to be 46 Gy. The recovery rate of salivary gland function after 1 year of RT was 72% in the RT alone group (n = 10), 56% in the conformal radiotherapy group (n = 15), and 44% in the bioradiotherapy group (n = 6). Conclusion: Scintigraphy revealed that the salivary glands recovered from post-RT hypofunction when decreased doses were administered. The determined tolerance dose of 46 Gy may guide the approach to minimizing associated xerostomia in RT. Advances in knowledge: In this study, the average tolerated dose to the salivary glands was 46 Gy.

Effect of brain radiotherapy strategies on prognosis of patients with EGFR-mutant lung adenocarcinoma with brain metastasis

Purpose Epidermal growth factor receptor (EGFR)-mutant lung cancers have a high risk of developing brain metastases (BM). Whole brain radiotherapy (WBRT), local radiotherapy, and WBRT + Boost are frequently used for treatment of BM. This retrospective study aimed to evaluate the difference in efficacy of these radiotherapy modes in patients with EGFR-mutant lung adenocarcinoma with BMs. Further, we determined the optimal radiotherapy regimen for patients based on Lung-molGPA. Methods and materials We retrospectively enrolled 232 patients with EGFR-mutant lung adenocarcinoma with BMs. Patients were divided into three groups based on the different modes of brain radiotherapy: WBRT group, local radiotherapy group, and WBRT + Boost group. Graded prognostic assessment for lung cancer using molecular markers (Lung molGPA), overall survival (OS), and intracranial progression-free survival (iPFS) were calculated. Kaplan–Meier was used to compare iPFS and OS in different groups. Results The median OS for the WBRT (n = 84), local radiotherapy (n = 65), and WBRT + Boost (n = 83) cohorts was 32.8, 59.1, and 41.7 months, respectively (P = 0.0002). After stratification according to the Lung-molGPA score, the median OS for the WBRT (n = 56), local radiotherapy (n = 19), and WBRT + Boost (n = 28) cohorts was 32.5, 30.9, and 30.8 months, respectively, in subgroup with score 1–2 (P = 0.5097). In subgroup with score 2.5–4, the median OS for the WBRT (n = 26), local radiotherapy (n = 45), and WBRT + Boost (n = 54) cohorts was 32, 68.4, and 51 months, respectively (P = 0.0041). Conclusion The present study showed that in patients with EGFR-mutant lung adenocarcinoma with BM, local radiotherapy and WBRT + Boost perform similarly well both in the subgroups with low and high scores of Lung-molGPA. Considering the side effect caused by whole brain radiotherapy, we recommended local radiotherapy as optimal brain radiation mode for those subtype lung cancer patients.

Repeat Breast-Conserving Surgery Versus Salvage Mastectomy for Ipsilateral Breast Tumour Recurrence After Breast-Conserving Surgery in Breast Cancer Patients: A Meta-Analysis

BackgroundSalvage mastectomy (SM) is the standard surgery for ipsilateral breast tumour recurrence (IBTR). However, whether repeat breast-conserving surgery (RBCS) is an alternative method remains unclear. We performed a meta-analysis to compare the effects of RBCS and SM after IBTR for breast-conserving surgery (BCS).MethodsWe searched PubMed, Cochrane, Wiley Online and Embase for controlled studies comparing RBCS and SM after IBTR for BCS (published between 1993 and 2019, published in English). Our main endpoints were the secondary local recurrence rate (SLRR), distant metastasis rate (DMR) and overall survival (OS). We used a random-effects model or fixed-effects model for data pooling.ResultsFifteen of the 424 eligible studies were ultimately included, and all studies were retrospective cohort studies (n=2532 participants). 1) SLRR: The SLRR of RBCS was higher than SM (pooled relative rate (pRR) = 1.87, 95% CI 1.22 - 2.86, P=0.004). Stratified analysis was performed according to whether radiotherapy was performed after salvage surgery (radiotherapy group: 2ndRT, no radiotherapy group: no-2ndRT), and the following results were revealed: pRR=0.43 (95% CI 0.20-0.95, P=0.04) for group 2ndRT; and pRR=2.30 (95% CI 1.72-3.06, P<0.00001) for group no-2ndRT. These results showed that the main cause of heterogeneity was salvage radiotherapy. 2) DMR: No significant difference in the DMR was observed between RBCS and SM (pRR = 0.61, 95% CI 0.37 - 1.01, P=0.05). 3) OS: No significant difference in OS was observed between RBCS and SM (pRR=0.65, 95% CI 0.39 - 1.08, P=0.10).ConclusionsThe SLRR of RBCS was higher than SM for ITBR after BCS, but survival was not affected. RBCS may be used as an alternative for IBTR patients after BCS with strict control for several indications, such as tumor size, recurrence interval and biological behavior, and attaching importance to subsequent salvage radiotherapy and systematic therapy.

The Efficacy of Radiotherapy in the Treatment of Hepatocellular Carcinoma with Distant Organ Metastasis

Background. Recently, radiotherapy has been used in the treatment of hepatocellular carcinoma (HCC). However, there is no study analyzing the efficacy of radiotherapy in cases of advanced HCC. The objective of this investigation was to determine the efficacy of radiotherapy in patients with HCC invading distant organs. Methods. The data of 2342 patients diagnosed between 2010 and 2015 with HCC invading distant organs were extracted from the SEER database. Propensity score matching (PSM) was used to reduce selection bias. Results. Before PSM, the median overall survival (mOS) and median cancer-specific survival (mCSS) in the radiotherapy group (mOS = 5 months, 95% CI: 4.5–5.5; mCSS = 5 months, 95% CI: 4.4–5.6) were longer than those in the nonradiotherapy group (mOS = 3 months, 95% CI: 2.8–3.2; mCSS = 3 months, 95% CI: 2.8–3.2; both P < 0.001 ). After PSM, mOS in the radiotherapy group (5 months, 95% CI: 4.5–5.5) was longer than that in the nonradiotherapy group (3 months, 95% CI: 2.6–3.4; P < 0.001 ), and the mCSS in the radiotherapy group (5 months, 95% CI: 4.4–5.6) was longer than that in the nonradiotherapy group (3 months, 95% CI: 2.6–3.4; P < 0.001 ). Before PSM, the multivariate analysis showed that all-cause and cancer-specific mortality rates were higher in the nonradiotherapy group than in the radiotherapy group. The adjusted Cox regression analysis for subgroups showed that, in the nonradiotherapy group, patients with bone metastases and multiorgan metastases had a worse survival than those in the radiotherapy group. Conclusion. HCC patients with metastases to distant organs obtain survival benefit from radiotherapy, particularly patients with bone metastases and multiorgan metastases.

RADT-27. EFFECTIVENESS ANALYSIS OF RADIOTHERAPY FOR INTRACRANIAL RECURRENT EPENDYMOMA

OBJECTIVE There is no standard treatment for recurrent ependymoma. This study aimed to investigated the role of radiotherapy in recurrent ependymoma. METHODS Retrospective analysis was performed on 49 cases of recurrent ependymoma diagnosed in Guangdong Sanjiu Brain Hospital from January 2008 to July 2020. Overall survival (OS) was calculated by Kaplan-Meier method and tested by Log-rank test. P &lt; 0.05 was considered statistically significant. RESULTS The median age was 7 years (range:1-57 yrs). Nineteen patients were with ependymoma WHO grade II while 30 were with grade III, respectively. Recurrence treatment: 14 cases received re-surgery, 23 cases received radiotherapy, among them 16 cases received re-radiotherapy. To May, 2021, the median follow-up time was 35 months (range 3-153). Median PFS time was 17 months after initial diagnosis, median PFS time was 8 months after treatment to recurrence disease, Median OS time is 39 months, and median OS time is 20 months after recurrence. The median survival time for recurrence was 48 months vs. 11 months (P =0.001) in the radiotherapy group vs. non-radiotherapy group,res; Re-radiotherapy combined with chemotherapy vs reradiotherapy alone (0.194); RRT combined with anti-angiogenesis therapy vs. RRT alone (0.688). CONCLUSION Radiotherapy can prolong the survival time of recurrent ependymoma, and concurrent therapy as chemotherapy or anti-angiogenesis therapy with RT does not seem to improve the prognosis. Therefore, radiotherapy can be used as the main treatment for recurrent ependymoma.

Prognostic impact of sarcopenia in patients with head and neck cancer treated with surgery or radiation: A meta-analysis

Background The objective of this study was to compare the prognostic impact of sarcopenia in patients with head and neck cancer (HNC) treated with surgery or radiation. Methods We systematically searched electronic databases to identify articles reporting the impact of sarcopenia on the prognosis of patients with HNC. Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall survival (OS), disease-free survival (DFS), and disease-specific survival (DSS) were extracted and pooled. HR according to treatment modality were estimated using random-effects models. Statistical analyses were carried out using the Comprehensive Meta-Analysis software. Results In total, 18 studies enrolling 3,233 patients were included. Sarcopenia was associated with poor OS in both surgery and radiotherapy groups (hazard ratio [HR] 2.50, 95% confidence interval [CI] 1.95–3.21; HR 1.63, 95% CI 1.40–1.90, respectively). The HR was significantly higher in the surgery group than in the radiotherapy group (p = 0.004), with similar results obtained for DFS (HR 2.59, 95% CI 1.56–4.31; HR 1.56, 95% CI 1.24–1.97 for the surgery and radiotherapy groups, respectively) and DSS (HR 2.96, 95% CI 0.73–11.95; HR 2.67, 95% CI 1.51–4.73 for the surgery and RT groups, respectively). Conclusions Sarcopenia was a poor prognostic factor for HNC, regardless of the treatment modality. However, the adverse effects of sarcopenia on survival were more prominent in the surgery group than in the radiotherapy group. Sarcopenia assessment is required for appropriate treatment decision-making.

Efficacy of Chemotherapy in Survival of Stage I Nasopharyngeal Carcinoma

PurposeTo identify whether chemoradiotherapy improves survival of stage I nasopharyngeal carcinoma (NPC).Materials and MethodsNPC patients were extracted from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Pathologically confirmed stage T1N0M0 (the 7th edition AJCC) were investigated. Overall survival (OS) and cancer-specific survival (CSS) were compared between the radiotherapy and chemoradiotherapy groups using the Kaplan-Meier method and propensity score matching (PSM) analyses.ResultsThis study included 91 (40.27%) patients in the chemoradiotherapy group and 135 (59.73%) patients in the radiotherapy group. Before PSM, chemoradiotherapy was associated with worse 3-year OS (74.31 vs 87.23%; P = 0.025) and 5-year OS (64.28 vs 83.12%; P = 0.001) compared to those associated with radiotherapy. Similarly, chemoradiotherapy showed worse 3-year CSS (87.01 vs 96.97%; P = 0.028) and 5-year CSS (80.39 vs. 96.97%; P = 0.002) than those of radiotherapy. After PSM, chemoradiotherapy revealed worse 5-year OS (63.10 vs. 82.49%; P = 0.031) and CSS (80.95 vs. 93.70%; P = 0.016) than radiotherapy. The multivariate regression analysis revealed that chemoradiotherapy was an independent risk prognostic factor for OS and CSS before and after PSM.ConclusionRadiotherapy alone is recommended for stage I NPC patients.

Preoperative vs postoperative radiotherapy in the management of rectal cancer: A systematic review

Purpose. The objective of this study is to review randomized clinical trials systematically that compare the outcomes of preoperative and postoperative radiotherapy in the management of rectal cancer regarding locoregional recurrance, disease free survival and overall survival.Methods. The relevant randomized clinical trials are searched via online databases such as Pubmed, Ebsco, and Proquest. RCTs publised in English between 2000 until 2020 are selected and reviewed systematically.Result. Locoregional recurrence at 5 years was statistically lower in preoperative radiotherapy group than in postoperative radiotherapy group based on two studies. Disease free survival at 5-years was statistically higher in preoprative radiotherapy group than the postoperative one based on two studies. Overall survival at 5 years was not statistically significant between two groups for each study.Conclusion. Preoperative radiotherapy is superior to postoperative radiotherapy for controlling locoregional recurrence and disease free survival, but both are equal in overall survival.

Synergistic Effect of Phloretin Combined With Radiotherapy on Lung Cancer

OBJECTIVE: The purpose of this study was to investigate the synergistic anti-tumor effects of phloretin (Ph) and radiotherapy (RT) on Lewis lung cancer (LLC), and the mechanisms involved. METHODS：The proliferative rate of Lewis cells treated with phloretin was detected by MTT assay; Clone formation experiments were used to demonstrate the synergistic effect of phloretin and radiotherapy; Mice engrafted with the LLC cells were given intraperitoneal injections of saline, phloretin with or without RT. Tumor models were established by laterally transplanting LLC cells in the right thigh of C57BL/J mice. They were randomly divided into four groups, namely saline group, phloretin group, radiotherapy group, phloretin combined with radiotherapy group. 10Gy radiotherapy was performed during the administration. PET-CT was used to detect 18F-FDG uptake in tumor tissue; immunohistochemistry was used to detect Ki67 expression in tumor tissue; cell apoptosis was detected by flow cytometry. RESULTS: Different concentrations of phloretin inhibited the proliferation of Lewis cells in a time and dose-dependent manner (P<0.05). The radiotherapy sensitization ratio (SER) of 50μg Phloretin was 1.645 in the LLC cells. The combination of Phloretin and RT increased survival compared to free Phloretin and RT (p<0.05), and prolonged tumor growth delay (TGD). Furthermore, the RT + Phloretin combination therapy significantly reduced 18F-FDG uptake, increased apoptosis and decreased the proliferation index (Ki67) in tumor cells compared to either monotherapy. CONCLUSION: phloretin combined with radiotherapy has a synergistic anti-tumor effect, possibly by promoting apoptosis, as well as inhibiting proliferation rate and glucose transport.

The role of postoperative radiotherapy in pN1 oral cavity cancer without extranodal extension

Background The administration of postoperative radiotherapy remains controversial in pN1 oral cavity cancer patients without extranodal extension. The aim is to determine whether postoperative radiotherapy reduces the neck recurrence rate and improves the survival outcomes of pN1 patients. Methods This study consecutively enrolled 1056 patients with newly diagnosed oral squamous cell carcinoma who underwent tumor wide excision and neck dissection from September 2002 to November 2019. One hundred two pN1 patients without extranodal extension were eligible for analysis. Then, a subgroup analysis of 40 patients was performed after patients with other adverse risk factors (positive margins, close margins, lymphovascular invasion, perineural invasion, tumor depth ≥ 10 mm, and poor histological differentiation) were excluded. Results Of the 102 eligible pN1 patients, 26 patients received surgery alone, and 76 received postoperative radiotherapy. No significant differences were observed in the neck recurrence rate (7.7% vs. 15.8%, p = 0.30). Similarly, in patients without other adverse risk factors, no significant differences were observed in the neck recurrence rate (5% vs. 20%, p = 0.15) between surgery alone group and postoperative radiotherapy group. Moreover, no significant difference was found in the neck recurrence-free survival rate, overall survival, and disease-specific survival (77.1% vs. 52.5%, p = 0.42, 83.5% vs. 64.5%, p = 0.81, and 88.2% vs. 67.9%, p = 0.34, respectively). Conclusion Postoperative radiotherapy did not significantly decrease the probability of neck recurrence and survival outcomes in pN1 patients without extranodal extension. Radical surgery alone may be considered sufficient treatment for pN1 patients without other adverse risk factors.