Proton Beam Radiotherapy as a Curative Alternative to Radiofrequency Ablation for Newly Diagnosed Hepatocellular Carcinoma.

BACKGROUND/AIM: This study aimed to compare the oncological outcomes of proton beam radiotherapy (PBT) with those of radiofrequency ablation (RFA) for newly diagnosed hepatocellular carcinoma (HCC). PATIENTS AND METHODS: This study included 323 patients who underwent PBT (n=40) or RFA (n=283) as a curative treatment for previously untreated HCC between October 2016 and June 2021. The primary endpoints were local progression and toxicity. RESULTS: The median follow-up was 3.4 years (range=1.1-5.7 years). In terms of portal vein tumor thrombosis, tumor size, alpha-fetoprotein, and prothrombin-induced by vitamin K absence-II, the PBT group had significantly more severe tumor burdens than those of the RFA group (p<0.0001, p<0.0001, p=0.0004, and p<0.0001, respectively). No significant difference was observed in cumulative local progression rate (10.4% in PBT vs. 7.8% in RFA at 3-years, p=0.895). Grade 3 or higher toxicity was reported in only one patient (0.4%) after RFA. Multivariable analysis demonstrated that treatment modality was not a significant prognostic factor for local progression (hazard ratio=1.05; 95% confidence interval=0.32-3.48; p=0.934). CONCLUSION: PBT demonstrated comparable local control with acceptable toxicity to RFA in newly diagnosed HCC. Therefore, PBT may be a valid alternative.

Concurrent nivolumab and external beam radiation therapy for hepatocellular carcinoma with macrovascular invasion: A phase II study.

Background and Aims: Nivolumab was the first immune checkpoint inhibitor approved for hepatocellular carcinoma (HCC). External beam radiation therapy (EBRT) is locally effective and may enhance the effectiveness of immunotherapy. This study investigated the efficacy and safety of concurrent nivolumab and EBRT in HCC with macrovascular invasion. Methods: In this phase II multicenter trial, patients with HCC and macrovascular invasion were concurrently treated with intravenous nivolumab (3 mg/kg every 2 weeks) and EBRT, followed by maintenance nivolumab until progression or unacceptable toxicity. Primary endpoints were progression-free survival (PFS) and safety, and secondary endpoints were overall survival, time-to-progression, objective response rate, and disease control rate. Results: Between January 2020 and June 2021, 50 patients (male 84%, median age 62.5) were enrolled; 47 (94.0%) and 13 (26.0%) with portal (Vp1/2, n = 21; Vp3, n = 23; Vp4, n = 3) and hepatic vein invasion, respectively. Patients received EBRT (median dose: 50 [IQR 43-50] Gy) after the first nivolumab dose. The median number of nivolumab doses was 8.5. Median PFS was 5.6 (90% CI 3.6-9.9) months. Median overall survival and time-to-progression were 15.2 (90% CI 10.8-19.6) and 5.6 (90% CI 3.6-9.9) months, respectively. The objective response rate and disease control rate were 36.0% and 74.0%, respectively. The median duration of response was 9.9 months. Of 35 patients with follow-up data, 23 received subsequent systemic treatment, including atezolizumab-bevacizumab, sorafenib, lenvatinib, and regorafenib. Treatment-related any grade adverse events (AEs) and grade 3/4 AEs occurred in 40 (80.0%) and 6 (12.0%) patients, respectively. Common treatment-related AEs included pruritus (38.0%) and rash (16.0%), with no treatment-related deaths. Conclusion: Concurrent nivolumab therapy and EBRT showed encouraging PFS with acceptable safety in patients with advanced HCC and macrovascular invasion. Impact and implications: Immune checkpoint inhibitors, the standard care for advanced hepatocellular carcinoma (HCC), show relatively poor therapeutic effects in patients with advanced HCC and macrovascular invasion. In this investigator-initiated phase II study, we, for the first time, show that concurrent external beam radiation therapy with nivolumab, an immune checkpoint inhibitor, led to encouraging progression-free survival in patients with HCC and macrovascular invasion. The concurrent treatment was tolerable without significant safety concerns. Further randomized studies investigating the combination of immunotherapy and external beam radiation therapy are required. ClinicalTrialsgov identifier: NCT04611165.

Impact and optimal timing of local therapy addition in borderline resectable or locally advanced pancreatic cancer after FOLFIRINOX chemotherapy.

Background: To evaluate the efficacy and optimal timing of local treatment in patients with borderline resectable (BR) or locally advanced pancreatic cancer (LAPC) treated with upfront FOLFIRINOX. Method: Between 2015 and 2020, 258 patients with pancreatic ductal adenocarcinoma (PDAC) were analysed. Treatment outcomes were compared between systemic treatment group (ST) and multimodality treatment groups (MT) using Kaplan-Meier curves and log-rank test. The MT were stratified as follows: FOLFIRINOX + radiation therapy (RT) (MT1), FOLFIRINOX + surgical resection (MT2), and FOLFIRINOX + RT + surgical resection (MT3). Results: With median follow-up period of 18 months, the 2-year overall survival (OS) for the ST was 22.0%, and it was significantly worse than MT (MT1, 46.3%; MT2, 65.7% and MT3; 90.2%; P < .001). The 2-year locoregional progression free survival (LRPFS) and overall PFS in ST were 10.7% and 7.0%, which were also significantly lower than those of MT (2-year LRPFS: MT1, 31.8%; MT2, 45.3%; MT3, 81.0%; 2-year overall PFS: MT1, 23.3%; MT2, 35.0%; MT3, 66.3%; P < .001). In time-varying multivariate Cox proportional hazard model, local treatment contributed to better treatment outcomes, with adjusted hazard ratios of 0.568 (95% confidence interval [CI], 0.398-0.811), 0.490 (95% CI, 0.331-0.726), and 0.656 (95% CI, 0.458-0.940) for OS, LRPFS, and overall PFS, respectively. The time window of 11-17 months after FOLFIRINOX appeared to demonstrate the maximal efficacy of local treatments in OS. Conclusions: Adding local treatment in BR/LAPC patients treated with upfront FOLFIRINOX seemed to contribute in improved treatment outcomes, and it showed maximal efficacy in OS when applied 11-17 months after the initiation of FOLFIRINOX. We suggest that administration of sufficient period of upfront FOLFIRINOX may intensify the efficacy of local treatments, and well controlled prospective trials are expected.

A meta-analysis comparing efficacy and safety between proton beam therapy versus carbon ion radiotherapy.

BACKGROUND: This study aimed to compare the outcomes of proton beam therapy (PBT) and carbon ion radiotherapy (CIRT) by a systematic review and meta-analysis of the existing clinical evidence. METHODS: A systematic literature search was performed to identify studies comparing the clinical outcomes of PBT and CIRT. The included studies were required to report oncological outcomes (local control [LC], progression-free survival [PFS], or overall survival [OS]) or adverse events. RESULTS: Eighteen articles comprising 1857 patients (947 treated with PBT and 910 treated with CIRT) were included in the analysis. The pooled analysis conducted for the overall population yielded average hazard ratios of 0.690 (95% confidence interval (CI), 0.493-0.967, p = 0.031) for LC, 0.952 (95% CI, 0.604-1.500, p = 0.590) for PFS, and 1.183 (0.872-1.607, p = 0.281) for OS with reference to CIRT. The subgroup analyses included patients treated in the head and neck, areas other than the head and neck, and patients with chordomas and chondrosarcomas. These analyses revealed no significant differences in most outcomes, except for LC in the subgroup of patients treated in areas other than the head and neck. Adverse event rates were comparable in both groups, with an odds ratio (OR) of 1.097 (95% CI, 0.744-1.616, p = 0.641). Meta-regression analysis for possible heterogeneity did not demonstrate a significant association between treatment outcomes and the ratio of biologically effective doses between modalities. CONCLUSION: This study highlighted the comparability of PBT and CIRT in terms of oncological outcomes and adverse events.

Defining Minimum Treatment Parameters of Ablative Radiation Therapy in Patients With Hepatocellular Carcinoma: An Expert Consensus.

PURPOSE: External beam radiation therapy (EBRT) is a highly effective treatment in select patients with hepatocellular carcinoma (HCC). However, the Barcelona Clinic Liver Cancer system does not recommend the use of EBRT in HCC due to a lack of sufficient evidence and intends to perform an individual patient level meta-analysis of ablative EBRT in this population. However, there are many types of EBRT described in the literature with no formal definition of what constitutes "ablative." Thus, we convened a group of international experts to provide consensus on the parameters that define ablative EBRT in HCC. METHODS AND MATERIALS: Fundamental parameters related to dose, fractionation, radiobiology, target identification, and delivery technique were identified by a steering committee to generate 7 Key Criteria (KC) that would define ablative EBRT for HCC. Using a modified Delphi (mDelphi) method, experts in the use of EBRT in the treatment of HCC were surveyed. Respondents were given 30 days to respond in round 1 of the mDelphi and 14 days to respond in round 2. A threshold of ≥70% was used to define consensus for answers to each KC. RESULTS: Of 40 invitations extended, 35 (88%) returned responses. In the first round, 3 of 7 KC reached consensus. In the second round, 100% returned responses and consensus was reached in 3 of the remaining 4 KC. The distribution of answers for one KC, which queried the a/b ratio of HCC, was such that consensus was not achieved. Based on this analysis, ablative EBRT for HCC was defined as a BED10 ≥80 Gy with daily imaging and multiphasic contrast used for target delineation. Treatment breaks (eg, for adaptive EBRT) are allowed, but the total treatment time should be ≤6 weeks. Equivalent dose when treating with protons should use a conversion factor of 1.1, but there is no single conversion factor for carbon ions. CONCLUSIONS: Using a mDelphi method assessing expert opinion, we provide the first consensus definition of ablative EBRT for HCC. Empirical data are required to define the a/b of HCC.

Impact of Intrahepatic External Beam Radiotherapy in Advanced Hepatocellular Carcinoma Patients Treated with Tyrosine Kinase Inhibitors.

Introduction: We aimed to investigate whether concurrent use of intrahepatic external beam radiotherapy (EBRT) is a viable option for patients with advanced hepatocellular carcinoma (HCC) undergoing tyrosine kinase inhibitor (TKI) therapy. Methods: A total of 453 patients with Barcelona Clinic Liver Cancer stage C (BCLC C) HCC, who started first-line treatment with TKI with intrahepatic EBRT (TKI + RT, n = 97) or TKI without intrahepatic EBRT (TKI, n = 356) were analyzed. The overall survival (OS) and progression-free survival (PFS) were compared in the overall cohort, patients who received at least 8 weeks of TKI treatment and a propensity score-matched cohort. Results: OS and PFS were better in those treated with TKI + RT than TKI (8.6 vs. 4.4 months and 4.5 vs. 2.3 months, respectively, with p < 0.001). Of note, the TKI + RT group demonstrated significantly longer time to intrahepatic tumor progression. In subgroup analysis, TKI + RT led to better OS than TKI in all subgroups and PFS was significantly improved in patients without extrahepatic metastasis and those with portal vein invasion. There was no significant difference in treatment discontinuation due to adverse events between the TKI + RT and TKI groups (32.0% vs. 37.9%, p = 0.34). Furthermore, patients treated with TKI + RT showed better liver function preservation over time compared to TKI without intrahepatic EBRT. Comparable treatment outcomes were observed between patients who received at least 8 weeks of TKI treatment and the propensity score-matched cohort. Conclusion: Concurrent intrahepatic EBRT targeting the liver and/or macrovascular invasion can be a viable option to improve outcomes of BCLC stage C patients receiving TKI therapy with an aim to control intrahepatic progression and preserving the liver function.

The Current Evidence of Intensity-Modulated Radiotherapy for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis.

Intensity-modulated radiotherapy (IMRT), an advanced RT technique, is a considerable treatment option for hepatocellular carcinoma (HCC). However, the distinguishing features of IMRT for HCC have not yet been clearly defined. A systematic review was performed according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. The PubMed/MedLine, Embase, Cochrane Library, Web of Science, and KoreaMed were used to screen eligible studies focusing on treatment outcomes after IMRT for HCC until 18 April 2023. A total of 1755 HCC patients receiving IMRT among 29 studies from 2009 to 2023 were selected for the meta-analysis. The median proportion of Barcelona Clinic Liver Cancer stage C was 100% (range: 38-100%). Nineteen studies used combined treatment. Pooled rates of response and 1-year local control were 58% (95% confidence interval [CI], 50-65%) and 84% (95% CI, 70-94%), respectively. The median overall survival (OS) was 13 months (range: 5-45 months), and pooled 1- and 3-year OS rates were 59% (95% CI, 52-66%), and 23% (95% CI, 14-33%), respectively. Pooled rates of classic radiation-induced liver disease (RILD), nonclassic RILD, and hepatic toxicity ≥ grade 3 were 2%, 4%, and 4%, respectively. Although most patients had advanced-stage HCC and combined treatment was commonly used, IMRT for HCC showed similar survival to existing RT modalities and relatively low severe toxicity.

Nomogram for predicting overall survival in patients with large (>5 cm) hepatocellular carcinoma based on real-world practice.

BACKGROUND/AIM: Patients with large (>5 cm) hepatocellular carcinoma (HCC) have limited treatment options, thus necessitating the identification of prognostic factors and the development of predictive tools. This study aimed to identify prognostic factors and to construct a nomogram to predict survival outcomes in patients with large HCC. METHODS: A cohort of 438 patients, who were diagnosed with large HCC at a tertiary hospital between 2015 and 2018, was analyzed. Cox proportional hazards models were used to identify key prognosticators of overall survival (OS), and an independent set of prognostic factors was used to develop a nomogram. The discrimination and calibration abilities of the nomogram were assessed and internal validation was performed using cross-validation and bootstrapping methods. RESULTS: During a median follow-up of 9.3 months, the median OS was 9.9 months, and the 1-year OS rate was 43.9%. Multivariable Cox regression analysis revealed that performance status, modified albumin-bilirubin grade, tumor size, extent of portal vein tumor thrombosis, and initial treatment significantly affected OS. The newly developed nomogram incorporating these variables demonstrated favorable accuracy (Harrell's concordance index, 0.807). CONCLUSIONS: The newly developed nomogram facilitated the estimation of individual survival outcomes in patients with large HCC, providing an acceptable level of accuracy.

External validation of subclassification system and progression pattern analysis in hepatocelluar carcinoma with macroscopic vascular invasion.

BACKGROUND AND PURPOSE: The present study aimed to validate the performance of a previously proposed subclassification model to predict prognosis after combined transarterial chemoembolization (TACE) and external beam radiotherapy (RT) for hepatocellular carcinoma (HCC) with macrovascular invasion (MVI) in an independent cohort that received the same first-line treatment for the patients with the similar disease extent characteristics, and analyzed the progression patterns as well as progression-free survival (PFS). MATERIALS AND METHODS: This study was conducted using prospectively collected data from the XXXXX HCC registry for newly diagnosed, previously untreated HCC between 2005 and 2018. Finally, 417 patients who satisfied the eligibility criteria were included and analyzed. RESULTS: The median PFS and overall survival (OS) were 5.2 and 13.9 months, respectively. Similar to a previous study, subclassification of patients into very low-, low-, intermediate-, and high-risk groups showed a median OS of 98.4, 18.3, 9.7, and 5.8 months, respectively (P < 0.001). Additionally, subclassification of patients into the very low-, low-, intermediate-, and high-risk groups showed median PFS of 18.7, 6.7, 3.3, and 2.3 months, respectively (p < 0.001). Overall, intrahepatic progression was the most common pattern of progression; however, extrahepatic progression was more common in the intermediate- and high-risk groups. CONCLUSION: The previously proposed subclassification model was successfully validated in an independent cohort. Treatment modification should be considered in the intermediate- and high-risk patient groups because of their frequent extrahepatic as well as intrahepatic progressions after combined TACE and RT.

FLASH dose rate calculation based on log files in proton pencil beam scanning therapy.

BACKGROUND: In radiation therapy, irradiating healthy normal tissues in the beam trajectories is inevitable. This unnecessary dose means that patients undergoing treatment risk developing side effects. Recently, FLASH radiotherapy delivering ultra-high-dose-rate beams has been re-examined because of its normal-tissue-sparing effect. To confirm the mean and instantaneous dose rates of the FLASH beam, stable and accurate dosimetry is required. PURPOSE: Detailed verification of the FLASH effect requires dosimeters and a method to measure the average and instantaneous dose rate stably for 2- or 3-dimensional dose distributions. To verify the delivered FLASH beam, we utilized machine log files from the built-in monitor chamber to develop a dosimetry method to calculate the dose and average/instantaneous dose rate distributions in two or three dimensions in a phantom. METHODS: To create a spread-out Bragg peak (SOBP) and deliver a uniform dose in a target, a mini-ridge filter was created with a 3D printer. Proton pencil beam line scanning plans of 2 × 2 cm2 , 3 × 3 cm2 , 4 × 4 cm2 , and round shapes with 2.3 cm diameter patterns delivering 230 MeV energy protons were created. The absorbed dose in the solid water phantom of each plan was measured using a PPC05 ionization chamber (IBA Dosimetry, Virginia, USA) in the SOBP region, and the log files for each plan were exported from the treatment control system console. Using these log files, the delivered dose and average dose rate were calculated using two methods: a direct method and a Monte Carlo (MC) simulation method that uses log file information. The computed and average dose rates were compared with the ionization chamber measurements. Additionally, instantaneous dose rates in user-defined volumes were calculated using the MC simulation method with a temporal resolution of 5 ms. RESULTS: Compared to ionization chamber dosimetry, 10 of 12 cases using the direct calculation method and 9 of 11 cases using the MC method had a dose difference below ±3%. Nine of 12 cases using the direct calculation method and 8 of 11 cases using the MC method had dose rate differences below ±3%. The average and maximum dose differences for the direct calculation and MC method were-0.17, +0.72%, and -3.15, +3.32%, respectively. For the dose rate difference, the average and maximum for the direct calculation and MC method were +1.26, +1.12%, and +3.75, +3.15%, respectively. In the instantaneous dose rate calculation with the MC simulation, a large fluctuation with a maximum of 163 Gy/s and a minimum of 4.29 Gy/s instantaneous dose rate was observed in a specific position, whereas the mean dose rate was 62 Gy/s. CONCLUSIONS: We successfully developed methods in which machine log files are used to calculate the dose and the average and instantaneous dose rates for FLASH radiotherapy and demonstrated the feasibility of verifying the delivered FLASH beams.

Radiotherapy trend in elderly hepatocellular carcinoma: retrospective analysis of patients diagnosed between 2005 and 2017.

PURPOSE: To report the trends of radiotherapy in the management of elderly patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: We retrospectively reviewed patients who entered HCC registry of Samsung Medical Center between 2005 and 2017. Patients who were 75 years or older at the time of registration were defined as elderly. They were categorized into three groups based on the year of registration. Radiotherapy characteristics were compared between the groups to observe differences by age groups and period of registration. RESULTS: Out of 9,132 HCC registry patients, elderly comprised 6.2% (566 patients) of the registry, and the proportion increased throughout the study period (from 3.1% to 11.4%). Radiotherapy was administered to 107 patients (18.9%) in elderly group. Radiotherapy utilization in the early treatment process (within 1 year after registration) has rapidly increased from 6.1% to 15.3%. All treatments before 2008 were delivered with two-dimensional or three-dimensional conformal radiotherapy, while more than two-thirds of treatments after 2017 were delivered with advanced techniques such as intensity-modulated radiotherapy, stereotactic body radiotherapy, or proton beam therapy. Overall survival (OS) of elderly was significantly worse than younger patients. However, for patients who received radiotherapy during the initial management (within one month after registration), there was no statistically significant difference in OS between age groups. CONCLUSION: The proportion of elderly HCC is increasing. Radiotherapy utilization and adoption of advanced radiotherapy technique showed a consistently increasing trend for the group of patients, indicating that the role of radiotherapy in the management of elderly HCC is expanding.

Bloch theorem dictated wave chaos in microcavity crystals.

Universality class of wave chaos emerges in many areas of science, such as molecular dynamics, optics, and network theory. In this work, we generalize the wave chaos theory to cavity lattice systems by discovering the intrinsic coupling of the crystal momentum to the internal cavity dynamics. The cavity-momentum locking substitutes the role of the deformed boundary shape in the ordinary single microcavity problem, providing a new platform for the in situ study of microcavity light dynamics. The transmutation of wave chaos in periodic lattices leads to a phase space reconfiguration that induces a dynamical localization transition. The degenerate scar-mode spinors hybridize and non-trivially localize around regular islands in phase space. In addition, we find that the momentum coupling becomes maximal at the Brillouin zone boundary, so the intercavity chaotic modes coupling and wave confinement are significantly altered. Our work pioneers the study of intertwining wave chaos in periodic systems and provide useful applications in light dynamics control.

One-Week versus Two-Week Chemoradiotherapy Followed by Curative Surgery in Rectal Cancer: Long-Term Comparative Pooled Analysis of Two Prospective Multicenter Phase II Trials.

PURPOSE: The optimal short-course chemotherapeutic regimen for rectal cancer has not been clearly defined until now. KROG 10-01 and KROG 11-02 prospective trials investigated the efficacy and safety of 1- and 2-week chemoradiotherapy (CRT), respectively. Materials and Methods: Patients eligible for KROG 10-01 and KROG 11-02 involved those with clinical T3-4N0-2M0 rectal cancers. They received preoperative CRT and total mesorectal excision. Patients in KROG 10-01 received radiation of 25 Gy in 5 fractions during 1 week with 5-fluorouracil/leucovorin. Patients in KROG 11-02 received radiation of 33 Gy in 10 fractions for 2 weeks with oral capecitabine. RESULTS: A total of 150 patients consisting of 70 patients from KROG 10-01 and 80 patients from KROG 11-02 were collectively analyzed. With a median follow-up time of 89.2 months, the 5-year overall survival rate was 86.5% in 1-week CRT and 85.3% in 2-week CRT (p=0.841). The 5-year recurrence-free survival rate was 83.5% in 1-week CRT and 77.1% in 2-week CRT (p=0.448). One patient (1.4%) in 1-week CRT and 11 patients (13.8%) in 2-week CRT exhibited pathologic complete regression (ypT0N0M0) after radiotherapy (p=0.006). One-week CRT had significantly higher acute hematologic (12.8% vs. 3.8%, p=0.040) and nonhematologic (38.6% vs. 16.3%, p=0.002) toxicity than 2-week CRT. CONCLUSION: Both 1- and 2-week schedules of CRT showed favorable survival outcomes after 7 years of follow-up. But, 2-week course achieved more increased tumor response and decreased acute toxicity than 1-week course.

Comprehensive immunoprofile analysis of prognostic markers in pancreaticobiliary tract cancers.

Pancreaticobiliary tract cancer has a poor prognosis with unmet needs in a new target treatment. Some studies have reported that an enhancement of T-cell immunity is associated with a good prognosis. The aim of this study is to investigate the immunoprofile as a prognostic marker of pancreaticobiliary tract cancers. Unresectable pancreatic ductal adenocarcinoma (PDAC, n = 80) and biliary tract cancer (BTC, n = 74) diagnosed between January 2012 and December 2018 in Samsung Medical Center were analyzed. Expression levels of CD8, FOXP3, PD-1, PD-L1, and CXCL13 in PDAC and BTC tissue samples were examined with immunohistochemical staining, which was evaluated with various clinical factors. In PDAC, higher degree of PD-L1 expression was significantly associated with shorter overall survival (OS) (p = 0.0095). On the other hand, higher infiltrations of PD-1+ immune cells (p = 0.0002) and CD8+ T cells (p = 0.0067) were associated with longer OS. In BTC, higher FOXP3+ (p = 0.0343) and CD8+ (p = 0.0028) cell infiltrations were associated with better survival. Low infiltration of CD8+ (p = 0.0148), FOXP3+ (p = 0.0208), PD-1+ (p = 0.0318) cells in PDAC, and FOXP3+ cells (p = 0.005) in BTC were considerably related to metastasis. In a combined evaluation of clinical factors and immunoprofiles, univariate analysis revealed that operation after chemotherapy (p < 0.0001), mass size (p = 0.0004), metastasis (p = 0.006), PD-L1 (p < 0.0001), PD-1 (p = 0.003) and CD8 (p = 0.0063) was significantly associated with OS in PDAC, and CD8 (p = 0.007) was statistically related to OS in BTC. In multivariate analysis, prognostic factors were operation after chemotherapy (p = 0.021) in PDAC and CD8 (p = 0.037) in BTC. Therefore, immunoprofile analysis of cells expressing CD8, FOXP3, PD-1, and PD-L1 might have prognostic values in patients with pancreaticobiliary tract cancers.

Radiotherapy for bone metastases of hepatocellular carcinoma: a hybrid systematic review with meta-analyses.

INTRODUCTION: External beam radiation therapy (EBRT) is commonly used as a palliative treatment for bone metastases of hepatocellular carcinoma (HCC). We planned a hybrid systematic review that meta-analyzed the efficacy and feasibility of EBRT and reviewed the literature to answer specific clinical questions. METHODS: The PubMed, Medline, Embase, and Cochrane Library databases were searched through 1 December 2021. Primary endpoints were overall survival (OS) and response rate (RR). Secondary endpoints were comparative data, including treatment response and survival related to dose escalation, number of metastases, and fractionation scheme. Formal pooled analyses were performed on the primary endpoints, and the secondary endpoints were systematically reviewed. Complications were also reviewed. RESULTS: Nineteen studies involving 1613 patients with HCC and bone metastases were included. The median OS was 6 months (range: 3-13 months). The pooled one-year OS was 23.1% (95% confidence interval [CI]: 18.4-28.6); pooled pain RR was 81.5% (95% CI: 76.4-85.7) and of pain complete remission was 26.5% (95% CI: 21.7-32.0). Pain response might be related to dose escalation, considering the moderate consistency of results and plausibility, with a low-quality grade of evidence†. Considering the indeterminate results, we cannot suggest that dose escalation is correlated with OS. The oligometastasis status might be related to better OS, considering the high consistency of results and plausibility with low to moderate quality of evidence. Hypofractionated EBRT might yield comparable efficacy to conventional EBRT, with a low-quality grade of evidence. There were few complications of grade ≥3, except for hematologic complications, which ranged from 11.5to 34%. CONCLUSION: EBRT is an efficient and feasible palliative option. Clinical consideration of hematologic complications is necessary. Future studies are needed to increase the quality of evidence for actual clinical questions. †Reference to a system of the American Society for Radiation Oncology primary liver cancer clinical guidelines.

A Phase II Study of Preoperative Chemoradiotherapy with Capecitabine Plus Simvastatin in Patients with Locally Advanced Rectal Cancer.

PURPOSE: The purpose of this phase II trial was to evaluate whether the addition of simvastatin, a synthetic 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, to preoperative chemoradiotherapy (CRT) with capecitabine confers a clinical benefit to patients with locally advanced rectal cancer (LARC). MATERIALS AND METHODS: Patients with LARC (defined by clinical stage T3/4 and/or lymph node positivity) received preoperative radiation (45-50.4 Gy in 25-28 daily fractions) with concomitant capecitabine (825 mg/m2 twice per day) and simvastatin (80 mg, daily). Curative surgery was planned 4-8 weeks after completion of the CRT regimen. The primary endpoint was pathologic complete response (pCR). The secondary endpoints included sphincter-sparing surgery, R0 resection, disease-free survival, overall survival, the pattern of failure, and toxicity. RESULTS: Between October 2014 and July 2017, 61 patients were enrolled; 53 patients completed CRT regimen and underwent total mesorectal excision. The pCR rate was 18.9% (n=10) by per-protocol analysis. Sphincter-sparing surgery was performed in 51 patients (96.2%). R0 resection was achieved in 51 patients (96.2%). One patient experienced grade 3 liver enzyme elevation. No patient experienced additional toxicity caused by simvastatin. CONCLUSION: The combination of 80 mg simvastatin with CRT and capecitabine did not improve pCR in patients with LARC, although it did not increase toxicity.

Clinical implication and management of rectal cancer with clinically suspicious lateral pelvic lymph node metastasis: A radiation oncologist's perspective.

Rectal cancer is the eighth most common malignancy worldwide. With the introduction of total mesorectal excision (TME) and neoadjuvant chemoradiation (NCRT), intrapelvic local control has been remarkably improved. However, lateral pelvic recurrence remains problematic, especially in patients with clinically suspicious lateral pelvic lymph node (LPLN). LPLN dissection has been applied for the management of LPLN metastasis, mainly in Japan and other Eastern countries, while the role of NCRT is more emphasized and LPLN dissection is performed in very limited cases in Western countries. However, the optimal management strategy for patients with rectal cancer with suspicious LPLN metastasis has not been determined. Herein, we review the latest studies on the optimal management of LPLN metastasis to suggest the most appropriate treatment policies according to current evidence and discuss future research directions.

Dual Oxidase 2 (DUOX2) as a Proteomic Biomarker for Predicting Treatment Response to Chemoradiation Therapy for Locally Advanced Rectal Cancer: Using High-Throughput Proteomic Analysis and Machine Learning Algorithm.

High-throughput mass-spectrometry-based quantitative proteomic analysis was performed using formalin-fixed, paraffin-embedded (FFPE) biopsy samples obtained before treatment from 13 patients with locally advanced rectal cancer (LARC), who were treated with concurrent chemoradiation therapy (CCRT) followed by surgery. Patients were divided into complete responder (CR) and non-complete responder (nCR) groups. Immunohistochemical (IHC) staining of 79 independent FFPE tissue samples was performed to validate the predictive ability of proteomic biomarker candidates. A total of 3637 proteins were identified, and the expression of 498 proteins was confirmed at significantly different levels (differentially expressed proteins-DEPs) between two groups. In Gene Ontology enrichment analyses, DEPs enriched in biological processes in the CR group included proteins linked to cytoskeletal organization, immune response processes, and vesicle-associated protein transport processes, whereas DEPs in the nCR group were associated with biosynthesis, transcription, and translation processes. Dual oxidase 2 (DUOX2) was selected as the most predictive biomarker in machine learning algorithm analysis. Further IHC validation ultimately confirmed DUOX2 as a potential biomarker for predicting the response of nCR to CCRT. In conclusion, this study suggests that the treatment response to RT may be affected by the pre-treatment tumor microenvironment. DUOX2 is a potential biomarker for the early prediction of nCR after CCRT.

Strong interlayer coupling and stable topological flat bands in twisted bilayer photonic Moiré superlattices.

The moiré superlattice of misaligned atomic bilayers paves the way for designing a new class of materials with wide tunability. In this work, we propose a photonic analog of the moiré superlattice based on dielectric resonator quasi-atoms. In sharp contrast to van der Waals materials with weak interlayer coupling, we realize the strong coupling regime in a moiré superlattice, characterized by cascades of robust flat bands at large twist-angles. Surprisingly, we find that these flat bands are characterized by a non-trivial band topology, the origin of which is the moiré pattern of the resonator arrangement. The physical manifestation of the flat band topology is a robust one-dimensional conducting channel on edge, protected by the reflection symmetry of the moiré superlattice. By explicitly breaking the underlying reflection symmetry on the boundary terminations, we show that the first-order topological edge modes naturally deform into higher-order topological corner modes. Our work pioneers the physics of topological phases in the designable platform of photonic moiré superlattices beyond the weakly coupled regime.