Consolidative chemotherapy after definitive concurrent chemoradiotherapy for esophageal squamous cell carcinoma patients: a population based cohort study.

BACKGROUND: The role of consolidative chemotherapy (CCT) for locally advanced esophageal squamous cell carcinoma (LA-ESCC) patients treated with definitive concurrent chemoradiotherapy (dCCRT) is unclear. We aimed to compare the overall survival (OS) of those treated with vs without CCT via a population based approach. METHODS: Eligible LA-ESCC patients diagnosed between 2011 and 2017 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance observable potential confounders between groups. The hazard ratio (HR) of death and incidence of esophageal cancer mortality (IECM) were compared between those with vs without CCT. We also evaluated the OS in supplementary analyses via alternative approaches. RESULTS: Our primary analysis consisted of 368 patients in whom covariates were well balanced after PS weighting. The HR of death when CCT was compared to without was 0.67 (95% confidence interval 0.52-0.86, P = 0.002). The HR of IECM was 0.66 (P = 0.04). The HR of OS remained similarly in favor of CCT in supplementary analyses. CONCLUSIONS: We found that CCT was associated with significantly improved OS for LA-ESCC patients treated with dCCRT. Randomized controlled trials were needed to confirm this finding.

Chemotherapy alone versus definitive concurrent chemoradiotherapy for cT4b esophageal squamous cell carcinoma: a population-based study.

BACKGROUND: The role of radiotherapy for cT4bNanyM0 esophageal squamous cell carcinoma (ESqCC) is relatively unclear, with both chemotherapy (C/T) alone and definitive concurrent chemoradiotherapy (dCCRT) being treatment options in the current guidelines. We aimed to compare the survival of dCCRT versus C/T for these patients via a population-based approach. METHODS: Eligible cT4b ESqCC patients diagnosed between 2011 and 2017 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance the observable potential confounders between groups. The hazard ratio (HR) of death and incidence of esophageal cancer mortality (IECM) were compared between dCCRT and C/T. We also evaluated OS in subgroups of either low or standard radiotherapy doses. RESULTS: Our primary analysis consisted of 247 patients in whom covariates were well balanced after PS weighing. The HR for death when dCCRT was compared with C/T was 0.36 (95% confidence interval 0.24-0.53, P < 0.001). Similar results were found for IECM. Statistical significance was only observed in the standard RT dose but not in the low dose in subgroup analyses. CONCLUSIONS: In this population-based nonrandomized study of cT4bNanyM0 ESqCC patients from Asia (Taiwan), we found that the use of radiotherapy with chemotherapy was associated with better overall survival than chemotherapy alone. Further studies (especially RCTs) are needed to confirm our findings.

Impact of the interval between neoadjuvant concurrent chemoradiotherapy and esophagectomy in the modern era: a population-based propensity-score-matched retrospective cohort study in Asia.

BACKGROUND: Neoadjuvant concurrent chemoradiotherapy (nCCRT) is one of the standard-of-care options for locally advanced esophageal squamous cell carcinoma (LA-ESqCC). The optimal interval between nCCRT and esophagectomy is unknown. METHODS: We constructed a propensity-score-matched [1:1 for long (8-12 weeks) vs short (4-7 weeks) intervals] cohort of LA-ESqCC patients who were diagnosed from 2011 to 2015 and treated with nCCRT via the Taiwan Cancer Registry and related databases. We compared the hazard ratios (HRs) of death using a robust variance estimator. We also evaluated alternative covariables, outcomes, and interval definitions. RESULTS: Our study population included 80 patients for each group; groups were balanced with respect to the observed covariables. There was no significant difference for the HR of death [1.22; 95% confidence interval 0.78-1.91, P = 0.39] when the long interval group was compared to the short interval group. There were also no significant differences when alternative covariables, outcomes, or interval definitions were evaluated. CONCLUSIONS: In this population-based study in modern Asia, we found that for LA-ESqCC patients treated with nCCRT and esophagectomy, overall survival was similar for either long or short intervals between nCCRT and esophagectomy. Randomized controlled trials are needed to verify this finding.

Neoadjuvant vs definitive concurrent chemoradiotherapy in locally advanced esophageal squamous cell carcinoma patients.

BACKGROUND: The optimal treatment for locally advanced esophageal squamous cell carcinoma remains unclear. We compared the clinical outcomes of neoadjuvant concurrent chemoradiotherapy (CCRT) followed by esophagectomy [the surgery group] and CCRT without surgery [the CCRT group] in patients with squamous cell carcinoma from an Asian population. METHODS: Eligible patients diagnosed from 2008 to 2015 were identified through the Taiwan Cancer Registry. To balance observable potential confounders, we constructed a 1:1 propensity score-matched cohort [surgery vs CCRT]. We compared the hazard ratios between the surgery and CCRT groups for death using a robust variance estimator. We also evaluated the outcomes of patients for freedom from local regional recurrence (FFLRR) and esophageal cancer-specific survival (ECSS). Extensive supplementary analyses were performed to examine the robustness of our findings. RESULTS: Our study population included 298 patients balanced with respect to the observed covariables. The hazard ratio of death was 0.56 [95% confidence interval 0.42~0.75] when surgery was compared to CCRT. The results remained significant in the FFLRR and ECSS outcomes. In the supplementary analyses, our results also remained significant when additional covariables were taken into consideration or when the definition of the index date was changed. CONCLUSIONS: When compared to definitive CCRT, neoadjuvant CCRT followed by esophagectomy was associated with improved overall survival for locally advanced esophageal squamous cell carcinoma. However, given the nonrandomized nature of the study and the sensitivity to potentially unmeasured confounders, our results should be interpreted cautiously.

A Population-based Study of the Effectiveness of Stereotactic Ablative Radiotherapy Versus Conventional Fractionated Radiotherapy for Clinical Stage I Non-small Cell Lung Cancer Patients.

BACKGROUND: Stereotactic ablative radiotherapy (SABR) is a promising option for non-operated early-stage non-small cell lung cancer (NSCLC) compared to conventional fractionated radiotherapy (CFRT). However, results from conclusive randomized controlled trials are not yet available. The aim of our study was to explore the effectiveness of SABR vs. CFRT for non-operated early-stage NSCLC. PATIENTS AND METHODS: We used a comprehensive population-based database to identify clinical stage I non-operated NSCLC patients in Taiwan diagnosed from 2007 to 2013 who were treated with either SABR or CFRT. We used inverse probability weighting and the propensity score as the primary form of analysis to address the nonrandomization of treatment. In the supplementary analyses, we constructed subgroups based on propensity score matching to compare survival between patients treated with SABR vs. CFRT. RESULTS: We identified 238 patients in our primary analysis. A good balance of covariates was achieved using the propensity score weighting. Overall survival (OS) was not significantly different between those treated with SABR vs. CFRT (SABR vs. CFRT: probability weighting adjusted hazard ratio [HR] 0.586, 95% confidence interval 0.264-1.101, p = 0.102). However, SABR was significantly favored in supplementary analyses. CONCLUSIONS: In this population-based propensity-score adjusted analysis, we found that OS was not significantly different between those treated with SABR vs. CFRT in the primary analysis, although significance was observed in the supplementary analyses. Our results should be interpreted with caution given the database (i.e., nonrandomized) approach used in our study. Overall, further studies are required to explore these issues.

Simultaneous detection of respiratory syncytial virus and human metapneumovirus by one-step multiplex real-time RT-PCR in patients with respiratory symptoms.

BACKGROUND: Both respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) are important viral pathogens causing respiratory tract infection (RTI) in the pediatric population. However, the clinical manifestations of RSV and hMPV infections are similar. Therefore, a reliable and rapid diagnostic tool is needed for diagnostic performance. METHODS: In order to optimize diagnosis efficiency of RTI, the aim of this study is to establish a rapid and advanced method for simultaneous detecting RSV and hMPV in nasopharyngeal aspirates specimens from patients. We designed a one-step triplex real-time RT-PCR (qRT-PCR) protocol using TaqMan probes for detecting RSV and hMPV. The plasmid clones containing RSV nucleoprotein gene and hMPV fusion gene were established as reference standards. We used virus culture supernatants from 86 known pediatric RTI patient to test the specificity and sensitivity of our assay. Then we used total 222 nasopharyngeal aspirates specimens from pediatric patients hospitalized with respiratory symptoms to evaluate our assay. RESULTS: Our one-step triplex qRT-PCR assay showed 100% sensitivity and specificity in testing RSV and hMPV in 86 known virus culture supernatants, with excellent linearity (R2 > 0.99) and reliable reproducibility (CV lower than 1.04%). This assay has a wide dynamic range 102-109copies/reaction (limit of detection; LOD = 100 copies/reaction). A total of 222 patients hospitalized with respiratory symptoms were enrolled for clinical evaluation. In these samples, our qRT-PCR assay detected 68 RSV positive and 18 hMPV positive cases. However, standard virus culture only detected 8 RSV positive cases and 0 hMPV cases. Based on this improved triplex qRT-PCR assay, we found that RSV infection was associated with severe inflammation by chest X-ray and occurrence of pneumonia which were not observed previously. CONCLUSIONS: In summary, we have developed a highly specific and sensitive one-step triplex qRT-PCR assay to detect hMPV and RSV simultaneously. This assay offers a valuable tool for routine diagnosis.

Teicoplanin therapy for MRSA bacteraemia: a retrospective study emphasizing the importance of maintenance dosing in improving clinical outcomes.

OBJECTIVES: To study the relationship between teicoplanin maintenance dosing and clinical outcomes in adults with MRSA bacteraemia. METHODS: MRSA bacteraemic patients who received three teicoplanin loading doses (6 mg/kg/12 h) followed by maintenance doses of 6 mg/kg/24 h (Group 1) or 6 mg/kg/12 h (Group 2) were retrospectively analysed. Evaluated on day 7, an unfavourable early clinical response referred to the presence of septic shock, persistent fever, persistent leucocytosis and/or persistent bacteraemia. Assessed at completion of teicoplanin therapy, an unfavourable final clinical response referred to clinical treatment failure. RESULTS: Compared with those in Group 1 (n = 122), patients in Group 2 (n = 82) had significantly higher rates of favourable early clinical response (P = 0.040) and final clinical response (P < 0.001) and a lower bloodstream-infection-related mortality rate (P = 0.018). Based on estimated ORs for favourable final clinical response in multivariate analysis, endocarditis (P < 0.001; OR 0.109, 95% CI 0.032-0.368), pneumonia (P < 0.001; OR 0.172, 95% CI 0.069-0.433), ICU admission (P < 0.001; OR 0.132, 95% CI 0.054-0.325) and high Pittsburgh bacteraemia score (P = 0.042; OR 0.187, 95% CI 0.021-0.457) were each a risk factor for an unfavourable final clinical response. Higher teicoplanin maintenance dosing contributed to a favourable final clinical response (P < 0.001; OR 8.800, 95% CI 3.602-21.502). Significantly higher favourable final clinical response rates were also found in patients with endocarditis (P = 0.007) and pneumonia (P < 0.001) in Group 2 compared with their counterparts in Group 1. CONCLUSIONS: These data highlight the importance of higher teicoplanin maintenance dosing, especially for severe infections due to MRSA.

Stereotactic ablative radiotherapy versus conventional fractionated radiotherapy for clinical early-stage non-small-cell lung cancer: a population-based study.

INTRODUCTION: The use of stereotactic ablative radiotherapy (SABR) over conventional fractionated radiotherapy (CFRT) for early-stage non-small-cell lung cancer (NSCLC) has been advocated, but is also debated in the literature. METHODS: In this retrospective cohort study, we adopted a target trial emulation framework to identify eligible patients diagnosed between 2011 and 2021 using the Taiwan Cancer Registry. In the primary analysis, the overall survival (OS) was the primary endpoint, whereas incidences of lung cancer mortality and radiation pulmonary toxicity were the secondary endpoints. Extensive supplementary analyses were also conducted. RESULTS: We included 351 patients in the primary analysis and found that the OS was not significantly different between the SABR (n = 290) and CFRT (n = 61) groups. The propensity score weighting adjusted hazard ratio of death was 0.75 (95% confidence interval 0.53-1.07, p = 0.118). The secondary endpoints and supplementary analyses showed no significant differences. CONCLUSIONS: The OS of patients with early-stage NSCLC treated with SABR was not significantly different from that of patients treated with CFRT alone. The results of the relevant ongoing clinical trials are eagerly awaited.

Efficacy of Definitive Radiotherapy for Patients with Clinical Stage IIIB or IIIC Lung Adenocarcinoma and Epidermal Growth Factor Receptor (EGFR) Mutations Treated Using First- or Second-Generation EGFR Tyrosine Kinase Inhibitors.

Background: The effectiveness of definitive radiotherapy (RT) for patients with clinical stage IIIB or IIIC lung adenocarcinoma and epidermal growth factor receptor (EGFR) mutations who received first- or second-generation EGFR tyrosine kinase inhibitors (TKIs) is unclear. Methods: Taiwan Cancer Registry data were used in this retrospective cohort study to identify adult patients diagnosed with EGFR-mutated stage IIIB or IIIC lung adenocarcinoma between 2011 and 2020. Patients treated with first- or second-generation EGFR TKIs were classified into RT and non-RT groups. Propensity score (PS) weighting was applied to balance covariates between groups. The primary outcome was overall survival (OS), and the incidence of lung cancer mortality (ILCM) was considered as a supplementary outcome. Additional supplementary analyses were conducted to assess the robustness of the findings. Results: Among 270 eligible patients, 41 received RT and 229 did not. After a median follow-up of 46 months, PS-weighted analysis showed the PS-weighted hazard ratio of death for the RT group compared to the non-RT group was 0.94 (95% CI: 0.61-1.45, p = 0.78). ILCM rates did not differ significantly between the two groups. Supplementary analyses yielded consistent results. Conclusion: The addition of definitive RT to first- or second-generation EGFR TKI treatment does not significantly improve OS of patients with EGFR-mutated stage IIIB or IIIC lung adenocarcinoma. NCT03521154NCT05167851.

Health Economic Evaluation of Proton Therapy for Lung Cancer: A Systematic Review.

BACKGROUND: To our knowledge, there have been no systematic reviews of health economic evaluations of proton therapy specific to lung cancer. METHODS: We conducted this systematic review according to the predefined protocol [PROSPERO CRD42022365869]. We summarized the results of the included studies via structured narrative synthesis. RESULTS: We identified four studies (all used passively scattered proton therapy) from 787 searches. Two cost analyses reported that proton therapy was more costly than photon therapy for early- or locally advanced-stage non-small cell lung cancer, one cost-utility analysis reported that proton therapy was dominated by nonproton therapy in early-stage non-small cell lung cancer, and one cost-utility analysis reported that proton therapy was not cost-effective (vs. photon) in locally advanced non-small cell lung cancer. CONCLUSIONS: Passively scattered proton therapy was more costly and not cost-effective than photon therapy for early- and locally advanced-stage non-small cell lung cancer. Further health economic evaluations regarding modern proton therapy (such as scanning beam) for common radiotherapy indications of lung cancer are eagerly awaited.

Neoadjuvant Chemotherapy With/Without Radiotherapy for Locally Advanced Rectal Cancer: A Nationwide Retrospective Cohort Study.

BACKGROUND/AIM: The role of neoadjuvant radiotherapy in the management of patients with locally advanced rectal cancer (LARC) who have undergone neoadjuvant systemic therapy has been the subject of recent debate. PATIENTS AND METHODS: We identified eligible rectal cancer patients diagnosed between 2011 and 2020 using data from the Taiwan Cancer Registry. In our primary analysis, we applied propensity score weighting (PSW) to balance observable potential confounders. We then compared the hazard ratio (HR) of death the neoadjuvant concurrent chemoradiotherapy (nCCRT) group and the neoadjuvant chemotherapy without radiotherapy (nCT) group. Additionally, we conducted a comprehensive assessment of other outcomes and performed various supplementary analyses. RESULTS: The primary analysis included 2,298 patients. The overall survival did not exhibit statistically significant differences, with a PSW-adjusted HR of 0.72 (95% confidence interval=0.33-1.56, p=0.40) when comparing the nCCRT group to the nCT group. These findings were consistent with those of other long-term outcomes and supplementary analyses. CONCLUSION: In patients with LARC who have undergone neoadjuvant systemic therapy, the addition of radiotherapy did not yield statistically significant differences in long-term clinical outcomes.

Adjuvant Concurrent Chemoradiotherapy Versus Adjuvant Chemotherapy Only in Locally Advanced Non-small-cell Lung Cancer With Involved Microscopic Resection Margin: A Population-based Cohort Study.

BACKGROUND/AIM: The role of adjuvant concurrent chemoradiotherapy (aCCRT) for locally advanced non-small cell lung cancer (LA-NSCLC) treated with radical surgery, with microscopically involved resection margin, has been debated without there being any direct evidence. In this study, we aimed to compare the outcomes between aCCRT and adjuvant chemotherapy (aCT). PATIENTS AND METHODS: Eligible patients diagnosed within 2011-2018 with LA-NSCLC were identified via the Taiwan Cancer Registry. We used propensity-score weighting to balance observable potential confounders, and then compared the hazard ratios of death between aCCRT-treated vs. aCT-treated groups. We also performed supplementary analyses using propensityscore matching. RESULTS: Our main study population consisted of 82 patients. The propensity score weight-adjusted hazard ratio of death for the aCCRT group was 0.74 (95% confidence interval=0.35-1.56, p=0.43). There was also no statistically significant difference in survival between groups in the supplementary analyses. CONCLUSION: For patients treated with radical but R1 resection for LA-NSCLC, there was no significant OS benefit from the addition of concurrent radiotherapy.

High vs. low radiotherapy dose in locally advanced esophageal squamous cell carcinoma patients treated with neoadjuvant concurrent chemoradiotherapy: an endemic area population-based study.

BACKGROUND: The optimal radiotherapy dose for locally advanced esophageal squamous cell carcinoma in endemic areas treated with neoadjuvant concurrent chemoradiotherapy is unclear. METHODS: Eligible patients diagnosed between 2010 and 2019 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance observable potential confounders. The hazard ratio (HR) of death was compared between high dose (50-50.4 Gy) and low dose (40-41.4 Gy) radiotherapy. We also evaluated other outcomes and performed supplementary analyses via an alternative approach. RESULTS: Our study population consisted of 644 patients. The PS weight-adjusted HR of death was 0.92 (95% confidence interval: 0.7-1.19, p = 0.51). There were no statistically significant differences for other outcomes or supplementary analyses. CONCLUSIONS: In this population-based study from an endemic area, we found no significant difference in overall survival between high vs. low radiotherapy doses.

High vs. Standard Radiotherapy Dose in Locally Advanced Rectal Adenocarcinoma Patients Treated With Neoadjuvant Long Course Chemoradiotherapy: A Population-based Study.

BACKGROUND/AIM: Locally advanced rectal cancer (LARC) patients are often treated with neoadjuvant long course chemoradiotherapy (NLCCRT) using 45-50.4 Gy conventional fractionated radiotherapy (CFRT). The role of radiotherapy dose escalation is unclear. PATIENTS AND METHODS: We identified LARC patients diagnosed from 2011 to 2016 and treated with NLCCRT using CFRT at high dose (54-60 Gy) or standard dose (45-50.4 Gy). In the primary analyses, we used propensity score (PS) weighting to balance the observable potential confounders. The hazard ratio (HR) of death and other endpoints were compared. We also evaluated these outcomes in supplementary analyses via an alternative approach. RESULTS: Our primary analysis included 459 patients. The HR of death when high dose was compared with standard dose was 0.62 (p=0.51). There were also no statistically significant differences in other endpoints or in the supplementary analyses. CONCLUSION: Overall, survival of LARC patients treated with NLCCT in CFRT was not significantly different between high or standard dose.

Effectiveness evaluation of adjuvant concurrent chemoradiotherapy for patients with positron emission tomography-staged esophageal squamous cell carcinoma after complete resection: A population-based cohort study.

BACKGROUND: The role of adjuvant concurrent chemoradiotherapy (ACCRT) is unclear for patients with esophageal squamous cell carcinoma (ESCC) who receive esophagectomy with clean margins. We compared the survival of the ACCRT versus observation groups for these patients staged with positron emission tomography (PET) via a population-based approach. METHODS: Eligible patients with locally advanced ESCC diagnosed between 2011 and 2017 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance observable potential confounders between groups. The hazard ratios (HR) of death and incidence of esophageal cancer mortality (IECM) were compared between the ACCRT and observation groups. We also evaluated overall survival (OS) in subgroups of either with or without lymph node metastases. RESULTS: Our primary analysis consisted of 105 patients in whom the covariates were well balanced after PS weighting. The HR for death when ACCRT was compared with observation was 0.58 (95% confidence interval 0.28-1.21, p = 0.15). The results were also not significantly different for IECM or in the subgroup analyses. CONCLUSION: We found that for patients with PET-staged ESCC who received esophagectomy with clean margins, the survival was not statistically different between ACCRT and observation. Further studies (randomized or larger sample size) are needed to clarify this issue.

Spread of ISCR1 elements containing blaDHA-1 and multiple antimicrobial resistance genes leading to increase of flomoxef resistance in extended-spectrum-beta-lactamase-producing Klebsiella pneumoniae.

Increasing resistance to quinolones, aminoglycosides, and/or cephamycins in extended-spectrum-ß-lactamase (ESBL)-producing Enterobacteriaceae exacerbates the already limited antibiotic treatment options for infections due to these microbes. In this study, the presence of resistance determinants for these antimicrobial agents was examined by PCR among ESBL-producing Klebsiella pneumoniae (ESBL-KP) isolates that caused bacteremia. Pulsed-field gel electrophoresis was used to differentiate the clonal relationship among the isolates studied. Transferability and the location of the resistance genes were analyzed by conjugation experiments, followed by DNA-DNA hybridization. Among the 94 ESBL-KP isolates studied, 20 isolates of flomoxef-resistant ESBL-KP were identified. They all carried a DHA-1 gene and were genetically diverse. CTX-M genes were found in 18 of the isolates. Among these DHA-1/CTX-M-producing K. pneumoniae isolates, ISCR1 was detected in 13 (72%) isolates, qnr genes (1 qnrA and 17 qnrB genes) were detected in 18 (100%), aac(6')-Ib-cr was detected in 11 (61%), and 16S rRNA methylase (all armA genes) was detected in 14 (78%). Four transconjugants were available for further analysis, and qnrB4, aac(6')-Ib-cr, armA, and bla(DHA-1) were all identified on these self-transferable bla(CTX-M)-carrying plasmids. The genetic environments of ISCR1 associated with armA, bla(DHA-1), and qnrB4 genes in the four transconjugants were identical. Replicon-type analysis revealed a FIIA plasmid among the four self-transferable plasmids, although the other three were nontypeable. The cotransfer of multiple resistance genes with the ISCR1 element-carrying plasmids has a clinical impact and warrants close monitoring and further study.

Safety of image-guided radiotherapy in definitive radiotherapy for localized prostate cancer: a population-based analysis.

OBJECTIVES: Image-guided radiotherapy (IGRT) is a recommended advanced radiation technique that is associated with fewer acute and chronic toxicities. However, one Phase III trial showed worse overall survival in the IGRT arm. The purpose of this observational study is to evaluate the impact of IGRT on overall survival. METHODS: We used the Taiwan Cancer Registry Database to enroll cT1-4N0M0 prostate cancer patients who received definitive radiotherapy between 2011 and 2015. We used inverse probability treatment weighting (IPW) to construct balanced IGRT and non-IGRT groups. We compared the overall survival of those in the IGRT and non-IGRT groups. Supplementary analyses (SA) were performed with alternative covariates in propensity score (PS) models and PS approaches. The incidence rates of prostate cancer mortality (IPCM), other cancer mortality (IOCM), and cardiovascular mortality (ICVM) were also evaluated. RESULTS: There were 360 patients in the IGRT arm and 476 patients in the non-IGRT arm. The median follow-up time was 50 months. The 5-year overall survival was 88% in the IGRT arm and 86% in the non-IGRT arm (adjusted hazard ratio [HR] of death = 0.93; 95% CI, 0.61-1.45; p = 0.77). The SA also showed no significant differences in the overall survival between those in the IGRT and non-IGRT arms. Both groups did not significantly differ in terms of IPCM, IOCM, and ICVM. CONCLUSIONS: The overall survival of localized prostate cancer patients who underwent IGRT was not inferior to those who did not. ADVANCES IN KNOWLEDGE: We demonstrated that the overall survival for prostate cancer patients with IGRT was not worse than those who did not undergo IGRT; this important outcome comparison has not been previously examined in the general population.

Optimal radiotherapy dose in cervical esophageal squamous cell carcinoma patients treated with definitive concurrent chemoradiotherapy: A population based study.

BACKGROUND: The optimal radiotherapy dose for locally advanced cervical esophageal squamous cell carcinoma (C-ESqCC) treated with definitive concurrent chemoradiotherapy (dCCRT) is unclear. Here, we aimed to compare the survival of those treated with high dose versus standard dose via a population based approach. METHODS: Eligible C-ESqCC patients diagnosed between 2011 and 2017 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance observable potential confounders between groups. The hazard ratio (HR) of death and incidence of esophageal cancer mortality (IECM) were compared between high (60-70 Gy) and standard dose (50-50.4 Gy). We also evaluated the outcome in supplementary analyses via alternative approaches. RESULTS: Our primary analysis consisted of 141 patients in whom covariates were well balanced after PS weighting. The HR of death when high dose was compared with standard dose was 0.65 (95% confidence interval [CI]: 0.4-1.03, p = 0.07). The HR of IECM was 0.74 (p = 0.45). The HR of OS remained similarly insignificant in supplementary analyses. CONCLUSIONS: We observed a trend in favor of high radiotherapy dose versus standard dose for C-ESqCC treated with dCCRT in this population-based nonrandomized study. Further studies are needed to confirm the findings of the study.

Effectiveness of Image-Guided Radiotherapy in Adjuvant Radiotherapy on Survival for Localized Breast Cancer: A Population-Based Analysis.

PURPOSE: Image-guided radiotherapy (IGRT) is an advanced radiotherapy technique to improve the radiotherapy delivery. We aimed to compare the overall survival (OS) for localized breast cancer (LBC) patient treated with adjuvant conventional fractionated radiotherapy (CFRT) using IGRT vs those without IGRT via a population-based analysis. PATIENTS AND METHODS: Eligible LBC patients diagnosed between 2011 and 2013 were identified via the Taiwan Cancer Registry. We used propensity score (PS) weighting to balance observable potential confounders between groups. The hazard ratio (HR) of death and other outcomes were compared between IGRT and non-IGRT. We also evaluated OS in various supplementary analyses. RESULTS: Our primary analysis included 6490 patients in whom covariates were well balanced after PS weighing. The HR for death when IGRT was compared with non-IGRT was 1.02 (95% confidence interval 0.80-1.31, P = 0.86). There were also no significant differences in the supplementary analyses. CONCLUSION: We found that OS of LBC patients treated with adjuvant CFRT was not statistically different between those treated with IGRT versus without IGRT. This was the first study in this regard to our knowledge but randomized controlled trials were needed to confirm our finding.