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1.
Cancer Research and Treatment ; : 189-195, 2023.
Article in English | WPRIM | ID: wpr-966477

ABSTRACT

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.

2.
Radiation Oncology Journal ; : 98-107, 2023.
Article in English | WPRIM | ID: wpr-1002774

ABSTRACT

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.

3.
Journal of Liver Cancer ; : 350-361, 2023.
Article in English | WPRIM | ID: wpr-1001322

ABSTRACT

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.

4.
Journal of Korean Academy of Oral Health ; : 140-150, 2023.
Article in English | WPRIM | ID: wpr-1000999

ABSTRACT

Objectives@#This study addressed longstanding issues in Korea’s public health dentist system by defining and standardizing job duties. A practical job description was drafted based on job analysis results to promote work efficiency and lay the groundwork for future educational programs. @*Methods@#The job description elements were selected and drafted based on previous studies.These drafts were revised and refined with expert panel validation. @*Results@#The main job duties of public health dentists encompass community oral health, dental practice, public oral health research, and special oral health, tailored for institutions such as health sub-centers, health centers, health clinics, national health organizations, and correctional facilities. For community oral health at public health subcenters involves 12 key duties including projects, education, and community engagement. Public health centers/clinics focus on 16 key duties mainly around health project planning and evaluation. Dental care across both settings has 15 main duties. Public oral health research emphasizes community surveys and epidemiology. Special oral health in correctional facilities covers 11 main duties including education and external resource linking. @*Conclusions@#It concluded that for the development of public health dentists in South Korea, it is necessary to develop public health dentist education programs to promote the performance of public health dentists and to equip them with the competencies necessary to perform such duties, focusing on job descriptions organized around the characteristics of workplaces and major tasks.

5.
Cancer Research and Treatment ; : 918-926, 2023.
Article in English | WPRIM | ID: wpr-999784

ABSTRACT

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.

6.
Korean Journal of Dental Materials ; (4): 125-134, 2021.
Article in English | WPRIM | ID: wpr-901900

ABSTRACT

The purpose of this study was to evaluate the effect of dicalcium phosphate dihydrate (DCPD) on the biocompatibility of mineral trioxide aggregate (MTA). DCPD was added to MTA (OrthoMTA) to suppress the increase in pH of MTA during hardening, and the change of pH, cytotoxicity, and subcutaneous inflammation reactions in mouse model were observed. The pH of OrthoMTA and DCPD-OrthoMTA at 1st day in phosphate-buffered saline was 12.5 and 12.8, respectively. At 19th day, the pH was 11.6 (OrthoMTA) and 8.8 (DCPD-OrthoMTA). Cytotoxicity of DCPD-OrthoMTA extract was lesser than that of OrthoMTA at high concentration (above 50%) (p<0.05). No significant differences appeared in subcutaneous inflammatory reactions among ProRoot MTA, OrthoMTA and DCPD-OrthoMTA. Therefore, it is likely that there is no apparent relationship between the cytotoxicity and subcutaneous inflammation in our experimental conditions.

7.
Clinical and Molecular Hepatology ; : 144-156, 2021.
Article in English | WPRIM | ID: wpr-874437

ABSTRACT

Background/Aims@#The abscopal effect, a rare phenomenon induced by radiation, can be reinforced by immunotherapy. Although radiation therapy and immunotherapy are increasingly being utilized for the treatment of hepatocellular carcinoma (HCC), whether immunotherapy could boost the abscopal effect remains unclear. In this study, we aimed to elucidate the immunological mechanisms underlying the abscopal effect induced by the combination of irradiation and immunotherapy in a murine HCC model. @*Methods@#A syngeneic HCC mouse model was established by transplanting murine Hepa 1–6 HCC cells into both hind legs of immunocompetent C57BL/6 mice. The tumors on the right hind legs were irradiated, and abscopal effects were observed in the non-irradiated tumors on the left hind leg with or without the coadministration of anti-programmed cell death 1 (PD-1) antibodies. Flow cytometric analyses were performed to analyze the distributions of immune cells infiltrating both irradiated and non-irradiated tumors and the tumor-draining lymph nodes (TDLNs). @*Results@#Administration of 16 Gy in two fractions more effectively inhibited the growth of both irradiated and nonirradiated tumors with higher tumor infiltration of cytotoxic T cells than 8 Gy did in a single fraction. The higher dose also increased activated dendritic cells in TDLNs, which had higher expression of the programmed cell death ligand 1. Coadministration of anti-PD-1 antibodies significantly enhanced the abscopal effect and increased infiltration of activated cytotoxic T cells in both irradiated and non-irradiated tumors. @*Conclusions@#Our findings show that adding anti-PD-1 therapy to radiation enhanced the abscopal effect in a syngeneic murine model of HCC.

8.
Korean Journal of Dental Materials ; (4): 125-134, 2021.
Article in English | WPRIM | ID: wpr-894196

ABSTRACT

The purpose of this study was to evaluate the effect of dicalcium phosphate dihydrate (DCPD) on the biocompatibility of mineral trioxide aggregate (MTA). DCPD was added to MTA (OrthoMTA) to suppress the increase in pH of MTA during hardening, and the change of pH, cytotoxicity, and subcutaneous inflammation reactions in mouse model were observed. The pH of OrthoMTA and DCPD-OrthoMTA at 1st day in phosphate-buffered saline was 12.5 and 12.8, respectively. At 19th day, the pH was 11.6 (OrthoMTA) and 8.8 (DCPD-OrthoMTA). Cytotoxicity of DCPD-OrthoMTA extract was lesser than that of OrthoMTA at high concentration (above 50%) (p<0.05). No significant differences appeared in subcutaneous inflammatory reactions among ProRoot MTA, OrthoMTA and DCPD-OrthoMTA. Therefore, it is likely that there is no apparent relationship between the cytotoxicity and subcutaneous inflammation in our experimental conditions.

9.
Radiation Oncology Journal ; : 52-59, 2020.
Article | WPRIM | ID: wpr-837101

ABSTRACT

Purpose@#To evaluate and compare the feasibilities of magnetic resonance (MR) image-based planning using synthetic computed tomography (sCT) versus CT (pCT)-based planning in helical tomotherapy for prostate cancer. @*Materials and Methods@#A retrospective evaluation was performed in 16 patients with prostate cancer who had been treated with helical tomotherapy. MR images were acquired using a dedicated therapy sequence; sCT images were generated using magnetic resonance for calculating attenuation (MRCAT). The three-dimensional dose distribution according to sCT was recalculated using a previously optimized plan and was compared with the doses calculated using pCT. @*Results@#The mean planning target volume doses calculated by sCT and pCT differed by 0.65% ± 1.11% (p = 0.03). Three-dimensional gamma analysis at a 2%/2 mm dose difference/distance to agreement yielded a pass rate of 0.976 (range, 0.658 to 0.986). @*Conclusion@#The dose distribution results obtained using tomotherapy from MR-only simulations were in good agreement with the dose distribution results from simulation CT, with mean dose differences of less than 1% for target volume and normal organs in patients with prostate cancer.

10.
Cancer Research and Treatment ; : 446-454, 2020.
Article | WPRIM | ID: wpr-831053

ABSTRACT

Purpose@#The purpose of this study was to investigate the role of carcinoembryonic antigen (CEA) levelsin improving the performance of magnetic resonance imaging (MRI) for the predictionof pathologic response after the neoadjuvant chemoradiation (NCRT) for patients with rectalcancer. @*Materials and Methods@#We retrospectively reviewed the medical records of 524 rectal cancer patients who underwentNCRT and total mesorectal excision between January 2009 and December 2014. Theperformances of MRI with or without CEA parameters (initial CEA and CEA dynamics) forprediction of pathologic tumor response grade (pTRG) were compared by receiver-operatingcharacteristic analysis with DeLong’s method. Cox regression was used to identify the independentfactors associated to pTRG and disease-free survival (DFS) after NCRT. @*Results@#The median follow-up was 64.0 months (range, 3.0 to 113.0 months). On multivariate analysis,poor tumor regression grade on MRI (mrTRG; p < 0.001), initial CEA (p < 0.001) andthe mesorectal fascia involvement on MRI before NCRT (mrMFI; p=0.054) showed associationwith poor pTRG. The mrTRG plus CEA parameters showed significantly improved performancesin the prediction of pTRG than mrTRG alone. All of mrTRG, mrMFI, and initial CEAwere also identified as independent factors associated with DFS. The initial CEA further discriminatedDFS in the subgroups with good mrTRG or that without mrMFI. @*Conclusion@#The CEA parameters significantly improved the performance of MRI in the prediction ofpTRG after NCRT for patients with rectal cancer. The DFS was further discriminated by initialCEA level in the groups with favorable MRI parameters.

11.
Journal of Liver Cancer ; : 136-142, 2019.
Article in English | WPRIM | ID: wpr-765716

ABSTRACT

Proton beam therapy (PBT) is one of the advances in radiotherapy techniques, which enables dose escalation with lower probability of radiation-induced liver or gastrointestinal injuries. However, the chest wall proximal to the tumor can be affected by high dose irradiation. Here, we report on a 58-year-old male patient who presented with huge hepatocellular carcinoma, received treatment with transarterial chemoembolization and PBT, and developed severe chest wall pain due to radiation-induced myositis. The patient's symptoms were controlled by oral steroids.


Subject(s)
Humans , Male , Middle Aged , Carcinoma, Hepatocellular , Liver , Myositis , Proton Therapy , Protons , Radiotherapy , Steroids , Thoracic Wall
12.
Cancer Research and Treatment ; : 1589-1599, 2019.
Article in English | WPRIM | ID: wpr-763202

ABSTRACT

PURPOSE: There is limited data on radiotherapy (RT) for hepatocellular carcinoma (HCC) in patients with Child-Pugh classification B (CP-B). This study aimed to evaluate the treatment outcomes of fractionated conformal RT in HCC patients with CP-B. MATERIALS AND METHODS: We retrospectively reviewed the data of HCC patients with CP-B treated with RT between 2009 and 2014 at 13 institutions in Korea. HCC was diagnosed by the Korea guideline of 2009, and modern RT techniques were applied. Fraction size was ≤ 5 Gy and the biologically effective dose (BED) ≥ 40 Gy₁₀ (α/β = 10 Gy). A total of 184 patients were included in this study. RESULTS: Initial CP score was seven in 62.0% of patients, eight in 31.0%, and nine in 7.0%. Portal vein tumor thrombosis was present in 66.3% of patients. The BED ranged from 40.4 to 89.6 Gy₁₀ (median, 56.0 Gy₁₀). After RT completion, 48.4% of patients underwent additional treatment. The median overall survival (OS) was 9.4 months. The local progression-free survival and OS rates at 1 year were 58.9% and 39.8%, respectively. In the multivariate analysis, non-classic radiation-induced liver disease (RILD) (p < 0.001) and additional treatment (p < 0.001) were the most significant prognostic factors of OS. Among 132 evaluable patients without progressive disease, 19.7% experienced non-classic RILD. Normal liver volume was the most predictive dosimetric parameter of non-classic RILD. CONCLUSION: Fractionated conformal RT showed favorable OS with a moderate risk non-classic RILD. The individual radiotherapy for CP-B could be cautiously applied weighing the survival benefits and the RILD risks.


Subject(s)
Humans , Carcinoma, Hepatocellular , Classification , Disease-Free Survival , Korea , Liver , Liver Diseases , Multivariate Analysis , Portal Vein , Radiotherapy , Radiotherapy, Conformal , Retrospective Studies , Thrombosis , Treatment Outcome
13.
Radiation Oncology Journal ; : 110-116, 2019.
Article in English | WPRIM | ID: wpr-761000

ABSTRACT

PURPOSE: This study aimed to identify prognostic factors for locoregional recurrence (LRR) in pT3N0 rectal cancer patients who were treated with surgery alone and had negative resection margin including circumferential resection margin (CRM) for optimal indication of adjuvant radiotherapy. MATERIALS AND METHODS: We reviewed patients with pT3N0 rectal cancer who were treated via upfront surgery and had no other adjuvant treatment from January 2003 to December 2012. In total, 122 patients who had negative resection margin including negative CRM were included in the analysis. RESULTS: The median follow-up period after surgery was 60 months (range, 3 to 161 months). During this time, 6 patients (4.9%) experienced LRR at the anastomotic site (4 patients), and regional lymphatic area (2 patients). The estimated 5-year rates of overall survival, recurrence-free survival, and LRR-free survival were 96.7%, 84.6%, and 94.0%, respectively. Multivariate analysis showed that level of tumor ≤5 cm was a significant prognostic factor for LRR-free survival (LRRFS) (p = 0.04; hazard ratio = 7.08; 95% confidence interval, 1.06–47.30). Patients with level of tumor ≤5 cm had an estimated 5-year LRRFS of 66.8%, which was much higher than 2.3% in patients with level of tumor >5 cm. There was no significant factor for recurrence-free survival or overall survival. CONCLUSION: In T3N0 rectal cancer, adjuvant chemoradiotherapy should be recommended in patients with level of tumor ≤5 cm for better local control. However, in patients with pT3N0 disease, negative resection margin, and level of tumor >5 cm, adjuvant chemoradiotherapy should be carefully suggested.


Subject(s)
Humans , Chemoradiotherapy, Adjuvant , Follow-Up Studies , Multivariate Analysis , Radiotherapy, Adjuvant , Rectal Neoplasms , Recurrence , Risk Factors
14.
Radiation Oncology Journal ; : 129-138, 2018.
Article in English | WPRIM | ID: wpr-741940

ABSTRACT

PURPOSE: This study was conducted to compare clinical outcomes and treatment-related toxicities after stereotactic body radiation therapy (SBRT) with two different dose regimens for small hepatocellular carcinomas (HCC) ≤3 cm in size. MATERIALS AND METHODS: We retrospectively reviewed 44 patients with liver-confined HCC treated between 2009 and 2014 with SBRT. Total doses of 45 Gy (n = 10) or 60 Gy (n = 34) in 3 fractions were prescribed to the 95% isodose line covering 95% of the planning target volume. Rates of local control (LC), intrahepatic failure-free survival (IHFFS), distant metastasis-free survival (DMFS), and overall survival (OS) were calculated using the Kaplan-Meier method. RESULTS: Median follow-up was 29 months (range, 8 to 64 months). Rates at 1 and 3 years were 97.7% and 95.0% for LC, 97.7% and 80.7% for OS, 76% and 40.5% for IHFFS, and 87.3% and 79.5% for DMFS. Five patients (11.4%) experienced degradation of albumin-bilirubin grade, 2 (4.5%) degradation of Child-Pugh score, and 4 (9.1%) grade 3 or greater laboratory abnormalities within 3 months after SBRT. No significant difference was seen in any oncological outcomes or treatment-related toxicities between the two dose regimens. CONCLUSIONS: SBRT was highly effective for local control without severe toxicities in patients with HCC smaller than 3 cm. The regimen of a total dose of 45 Gy in 3 fractions was comparable to 60 Gy in efficacy and safety of SBRT for small HCC.


Subject(s)
Humans , Carcinoma, Hepatocellular , Dose Fractionation, Radiation , Follow-Up Studies , Methods , Radiosurgery , Retrospective Studies
15.
Radiation Oncology Journal ; : 25-34, 2018.
Article in English | WPRIM | ID: wpr-741931

ABSTRACT

PURPOSE: This study aimed to evaluate the initial outcomes of proton beam therapy (PBT) for hepatocellular carcinoma (HCC) in terms of tumor response and safety. MATERIALS AND METHODS: HCC patients who were not indicated for standard curative local modalities and who were treated with PBT at Samsung Medical Center from January 2016 to February 2017 were enrolled. Toxicity was scored using the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Tumor response was evaluated using modified Response Evaluation Criteria in Solid Tumors (mRECIST). RESULTS: A total of 101 HCC patients treated with PBT were included. Patients were treated with an equivalent dose of 62–92 GyE10. Liver function status was not significantly affected after PBT. Greater than 80% of patients had Child-Pugh class A and albumin-bilirubin (ALBI) grade 1 up to 3-months after PBT. Of 78 patients followed for three months after PBT, infield complete and partial responses were achieved in 54 (69.2%) and 14 (17.9%) patients, respectively. CONCLUSION: PBT treatment of HCC patients showed a favorable infield complete response rate of 69.2% with acceptable acute toxicity. An additional follow-up study of these patients will be conducted.


Subject(s)
Humans , Carcinoma, Hepatocellular , Follow-Up Studies , Liver , Proton Therapy , Protons , Radiotherapy , Response Evaluation Criteria in Solid Tumors
16.
Cancer Research and Treatment ; : 506-517, 2018.
Article in English | WPRIM | ID: wpr-714222

ABSTRACT

PURPOSE: This study was conducted to validate the prognostic influence of treatment response among patients with positive circumferential resection margin for locally advanced rectal cancer. MATERIALS AND METHODS: Clinical data of 197 patientswith positive circumferential resection margin defined as ≤ 2 mm after preoperative chemoradiotherapy followed by total mesorectal excision between 2004 and 2009 were collected for this multicenter validation study. All patients underwent median 50.4 Gy radiation with concurrent fluoropyrimidine based chemotherapy. Treatment response was dichotomized to good response, including treatment response of grade 2 or 3, and poor response, including grade 0 or 1. RESULTS: After 52 months median follow-up, 5-year overall survival (OS) for good responders and poor responders was 79.1% and 48.4%, respectively (p < 0.001). In multivariate analysis, circumferential resection margin involvement and treatment response were a prognosticator for OS and locoregional recurrence-free survival. In subgroup analysis, good responders with close margin showed significantly better survival outcomes for survival. Good responders with involved margin and poor responders with close margin shared similar results, whereas poor responders with involved margin had worst survival (5-year OS, 81.2%, 57.0%, 50.0%, and 32.4%, respectively; p < 0.001). CONCLUSION: Among patients with positive circumferential resection margin after preoperative chemoradiotherapy, survival of the good responders was significantly better than poor responders. Subgroup analysis revealed that definition of positive circumferential resection margin may be individualized as involvement for good responders, whereas ≤ 2 mm for poor responders.


Subject(s)
Humans , Chemoradiotherapy , Drug Therapy , Follow-Up Studies , Multivariate Analysis , Radiation Dosage , Rectal Neoplasms
17.
Journal of Liver Cancer ; : 80-85, 2018.
Article in Korean | WPRIM | ID: wpr-765675

ABSTRACT

Although first-line treatment option for single, small sized hepatocellular carcinoma in patients with preserved liver function and good performance status is resection or ablation, sometimes these modalities cannot be applied for variable reasons. For them, alternative options such as transarterial chemoeombolization, ethanol injection, and external radiation therapy can be considered, with variable success rates. Herein, we describe 45 year-old male who presented with a single small tumor located at caudate lobe. After multi-disciplinary discussion, the patient was treated with proton beam therapy, which resulted in favorable treatment outcome.


Subject(s)
Humans , Male , Carcinoma, Hepatocellular , Ethanol , Liver , Proton Therapy , Protons , Treatment Outcome
18.
Cancer Research and Treatment ; : 1039-1050, 2018.
Article in English | WPRIM | ID: wpr-715623

ABSTRACT

PURPOSE: A pooled analysis of multi-institutional trials was performed to analyze the effect of surgical timing on tumor response by comparing short course concurrent chemoradiotherapy (CCRT) with long course CCRT followed by delayed surgery in locally advanced rectal cancer. MATERIALS AND METHODS: Three hundred patients with cT3-4N0-2 rectal adenocarcinoma were included. Long course patients from KROG 14-12 (n=150) were matched 1:1 to 150 short course patients from KROG 10-01 (NCT01129700) and KROG 11-02 (NCT01431599) according to stage, age, and other risk factors. The primary endpoint was to determine the interval between surgery and the last day of neoadjuvant CCRT which yields the best tumor response after the short course and long course CCRT. Downstaging was defined as ypT0-2N0M0 and pathologic complete response (ypCR) was defined as ypT0N0M0, respectively. RESULTS: Both the long and short course groups achieved lowest downstaging rates at < 6 weeks (long 20% vs. short 8%) and highest downstaging rates at 6-7 weeks (long 44% vs. short 40%). The ypCR rates were lowest at < 6 weeks (both long and short 0%) and highest at 6-7 weeks (long 21% vs. short 11%) in both the short and long course arms. The downstaging and ypCR rates of long course group gradually declined after the peak at 6-7 weeks and those of the short course group trend to constantly increase afterwards. CONCLUSION: It is optimal to perform surgery at least 6 weeks after both the short course and long course CCRT to obtain maximal tumor regression in locally advanced rectal adenocarcinoma.


Subject(s)
Humans , Adenocarcinoma , Arm , Chemoradiotherapy , Rectal Neoplasms , Risk Factors
19.
Cancer Research and Treatment ; : 61-69, 2017.
Article in English | WPRIM | ID: wpr-6993

ABSTRACT

PURPOSE: The aim of this study was to examine patterns of radiotherapy (RT) in Korean patients with hepatocellular carcinoma (HCC) according to the evolving guideline for HCC established by the Korean Liver Cancer Study Group-National Cancer Center (KLCSG-NCC). MATERIALS AND METHODS: We reviewed 765 patients with HCC who were treated with RT between January 2011 and December 2012 in 12 institutions. RESULTS: The median follow-up period was 13.3 months (range, 0.2 to 51.7 months). Compared with previous data between 2004 and 2005, the use of RT as a first treatment has increased (9.0% vs. 40.8%). Increased application of intensity-modulated RT resulted in an increase in radiation dose (fractional dose, 1.8 Gy vs. 2.5 Gy; biologically effective dose, 53.1 Gy10 vs. 56.3 Gy10). Median overall survival was 16.2 months, which is longer than that reported in previous data (12 months). In subgroup analysis, treatments were significantly different according to stage (p < 0.001). Stereotactic body RT was used in patients with early HCC, and most patients with advanced stage were treated with three-dimensional conformal RT. CONCLUSION: Based on the evolving KLCSG-NCC practice guideline for HCC, clinical practice patterns of RT have changed. Although RT is still used mainly in advanced HCC, the number of patients with good performance status who were treated with RT as a first treatment has increased. This change in practice patterns could result in improvement in overall survival.


Subject(s)
Humans , Carcinoma, Hepatocellular , Follow-Up Studies , Liver Neoplasms , Practice Patterns, Physicians' , Radiation Oncology , Radiotherapy
20.
Radiation Oncology Journal ; : 78-89, 2017.
Article in English | WPRIM | ID: wpr-156647

ABSTRACT

PURPOSE: To determine the optimal radiotherapy technique for gastric mucosa-associated lymphoid tissue lymphoma (MALToma), we compared the dosimetric parameters and the risk of solid secondary cancer from scattered doses among anterior-posterior/posterior-anterior parallel-opposed fields (AP/PA), anterior, posterior, right, and left lateral fields (4_field), 3-dimensional conformal radiotherapy (3D-CRT) using noncoplanar beams, and intensity-modulated radiotherapy composed of 7 coplanar beams (IMRT_co) and 7 coplanar and noncoplanar beams (IMRT_non). MATERIALS AND METHODS: We retrospectively generated 5 planning techniques for 5 patients with gastric MALToma. Homogeneity index (HI), conformity index (CI), and mean doses of the kidney and liver were calculated from the dose-volume histograms. Applied the Biological Effects of Ionizing Radiation VII report to scattered doses, the lifetime attributable risk (LAR) was calculated to estimate the risk of solid secondary cancer. RESULTS: The best value of CI was obtained with IMRT, although the HI varied among patients. The mean kidney dose was the highest with AP/PA, followed by 4_field, 3D-CRT, IMRT_co, and IMRT_non. On the other hand, the mean liver dose was the highest with 4_field and the lowest with AP/PA. Compared with 4_field, the LAR for 3D-CRT decreased except the lungs, and the LAR for IMRT_co and IMRT_non increased except the lungs. However, the absolute differences were much lower than <1%. CONCLUSION: Tailored RT techniques seem to be beneficial because it could achieve adjacent organ sparing with very small and clinically irrelevant increase of secondary solid cancer risk compared to the conventional techniques.


Subject(s)
Humans , Hand , Kidney , Liver , Lung , Lymphoma, B-Cell, Marginal Zone , Planning Techniques , Radiation, Ionizing , Radiotherapy , Radiotherapy, Conformal , Radiotherapy, Intensity-Modulated , Retrospective Studies , Risk Assessment , Stomach
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