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Kim YJ, Kim JH, Kim K, Kim HJ, Chie EK, Shin KH, Wu HG, Kim IH. The Feasibility of Spinal Stereotactic Radiosurgery for Spinal Metastasis with Epidural Cord Compression. Cancer Res Treat 2019; 51:1324-1335. [PMID: 30699497 PMCID: PMC6790856 DOI: 10.4143/crt.2018.653] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/28/2019] [Indexed: 01/27/2023] Open
Abstract
PURPOSE The purpose of this study was to investigate the effectiveness and safety of spinal stereotactic radiosurgery (SRS) in treating spinal metastasis with epidural spinal cord compression (ESCC). Materials and Methods During 2013-2016, 149 regions of spinal metastasis in 105 patients treated with singlefraction (12-24 Gy) spinal SRS were reviewed. Cord compression of Bilsky grade 2 (with visible cerebrospinal fluid [CSF]) or 3 (no visible CSF) was defined as ESCC. Local progression (LP) and vertebral compression fracture (VCF) rates after SRS were evaluated using multivariate competing-risk regression analysis. RESULTS The 1-year cumulative incidences of LP for Bilsky grades 0 (n=80), 1 (n=39), 2 (n=21), and 3 (n=9) were 3.0%, 8.4%, 0%, and 24.9%, respectively. Bilsky grade 2 ESCC did not significantly increase the LP rate (no LP for grade 2). The 1-year cumulative incidences of VCF for Bilsky grades 0, 1, 2, and 3 were 6.6%, 5.2%, 17.1%, and 12.1%, respectively. ESCC may increase VCF risk (subhazard ratio [SHR] for grade 2, 5.368; p=0.035; SHR for grade 3, 2.215; p=0.460). Complete or partial pain response rates after SRS were 79%, 78%, 53%, and 63% for Bilsky grades 0, 1, 2, and 3, respectively (p=0.008). No neurotoxicity of grade ≥ 3 was observed. CONCLUSION Spinal SRS for spinal metastasis with Bilsky grade 2 ESCC did not increase the LP rate, was not associated with severe neurotoxicity, and showed moderate VCF and pain response rates. Bilsky grade 3 had a high LP rate.
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Kim JS, Keam B, Heo DS, Han DH, Rhee CS, Kim JH, Jung KC, Wu HG. The Prognostic Value of Albumin-to-Alkaline Phosphatase Ratio before Radical Radiotherapy in Patients with Non-metastatic Nasopharyngeal Carcinoma: A Propensity Score Matching Analysis. Cancer Res Treat 2019; 51:1313-1323. [PMID: 30699498 PMCID: PMC6790835 DOI: 10.4143/crt.2018.503] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 01/28/2019] [Indexed: 02/06/2023] Open
Abstract
Purpose We first analyzed the prognostic power of albumin-to-alkaline phosphatase ratio (AAPR) before radical radiotherapy (RT) in non-metastatic nasopharyngeal carcinoma (NPC) patients. Materials and Methods The records of 170 patients with biopsy-proven, non-metastatic NPC treated by radical RT between 1998 and 2016 at our institution were retrospectively reviewed. Median follow-up duration was 50.6 months. All patients received intensity-modulated RT and cisplatin based chemotherapy before, during, or after RT. The major treatment of patients was based on concurrent chemoradiotherapy (92.4%). The AAPR was calculated by the last value of both albumin and alkaline phosphatase within 1 month immediately preceding RT. The optimal cut-off level of AAPR was determined by using Cutoff Finder, a web-based system. Propensity score matching (PSM) analysis was performed. Results The optimal cut-off level of AAPR was 0.4876. After PSM analysis of whole cohort, an AAPR was not related to survival outcomes. In PSM analysis for patients with locoregionally advanced nasopharyngeal carcinoma (LA-NPC), an AAPR ≥ 0.4876 was related to better overall survival (OS), progression-free survival (PFS), and locoregional relapse–free survival (LRRFS) (OS: hazard ratio [HR], 0.341; 95% confidence interval [CI], 0.144 to 0.805; p=0.014; PFS: HR, 0.416; 95% CI, 0.189 to 0.914; p=0.029; and LRRFS: HR, 0.243; 95% CI, 0.077 to 0.769; p=0.016, respectively). Conclusion The AAPR, inexpensive and readily derived from a routine blood test, could be an independent prognostic factor for patients with LA-NPC. And it might help physicians determine treatment plans by identifying the patient's current status. Future prospective clinical trials to validate its prognostic value are needed.
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Kim E, Wu HG, Keam B, Kim TM, Kim DW, Paeng JC, Kim HJ, Chang JH. Significance of 18F-FDG PET Parameters According to Histologic Subtype in the Treatment Outcome of Stage III Non–small-cell Lung Cancer Undergoing Definitive Concurrent Chemoradiotherapy. Clin Lung Cancer 2019; 20:e9-e23. [DOI: 10.1016/j.cllc.2018.08.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 08/23/2018] [Accepted: 08/24/2018] [Indexed: 12/17/2022]
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Choi CH, Park SY, Park JM, Wu HG, Kim JH, Kim JI. Comparison of the IPSA and HIPO algorithms for interstitial tongue high-dose-rate brachytherapy. PLoS One 2018; 13:e0205229. [PMID: 30286187 PMCID: PMC6171910 DOI: 10.1371/journal.pone.0205229] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 09/21/2018] [Indexed: 11/30/2022] Open
Abstract
Purpose This study aimed to compare the inverse planning simulated annealing (IPSA) stochastic algorithm with the hybrid inverse planning and optimization (HIPO) algorithm for interstitial tongue high-dose-rate (HDR) brachytherapy. Methods Twenty patients who received radiotherapy for tongue cancer using interstitial HDR brachytherapy were retrospectively selected for this study. Oncentra Brachy v. 4.3 was used for IPSA and HIPO planning. Four to eight fixed catheter configurations were determined according to the target shape. During the optimization process, predetermined constrain values were used for each IPSA and HIPO plan. The dosimetric parameters and dwell time were analyzed to evaluate the performances of the plans. Results The total dwell time using IPSA was 4 seconds longer than that of HIPO. The number of active positions per catheter for the IPSA plans were approximately 2.5 fewer than those of the HIPO plans. The dose-volumetric parameters related to the clinical target volume with IPSA were lower than those with HIPO. In terms of the dose-volumetric parameters related to normal tissue, HIPO tended to associate with slightly higher values than IPSA, without statistical significance. After GrO, the target coverages were satisfied to clinical goal for all patients. The total dwell times was approximately increased by 10%. Conclusions The IPSA and HIPO dose optimization algorithms generate similar dosimetric results. In terms of the dwell time, HIPO appears to be more beneficial.
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Chun SJ, Keam B, Heo DS, Kim KH, Sung MW, Chung EJ, Kim JH, Jung KC, Kim JH, Wu HG. Optimal timing for salvage surgery after definitive radiotherapy in hypopharyngeal cancer. Radiat Oncol J 2018; 36:192-199. [PMID: 30309210 PMCID: PMC6226141 DOI: 10.3857/roj.2018.00311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 08/06/2018] [Indexed: 12/23/2022] Open
Abstract
Purpose Use of radiotherapy combined with chemotherapy is increasing in hypopharyngeal cancer. However, many show residual tumor after radiotherapy. Timing for treatment evaluation and salvage therapy is essential. However, optimal timing for salvage surgery has not been suggested. In this study, we tried to evaluate optimal timing for salvage surgery. Methods and Materials Patients who were diagnosed with hypopharyngeal squamous cell carcinoma between 2006 and 2015 were retrospectively analyzed. All patients received definitive radiotherapy with or without chemotherapy. Response of all treated patients were analyzed at 1, 3, and 6 months after radiotherapy. Any patients with progression before 6 months were excluded. Results A total of 54 patients were analyzed. Complete remission (CR) rates at 1 month (CR1), 3 months (CR3) and 6 months (CR6) were 66.7%, 81.5%, and 90.7%, respectively. Non-CR at 1 month (NCR1), 3 months (NCR3), and 6 months (NCR6) showed poor locoregional recurrence-free survival rates (1-year rates of 63.7%, 66.7%, and 0.0%, respectively) compared to CR1, CR3, and CR6 (1-year rates 94.3%, 88.0%, and 91.5%, respectively). Particularly significant differences were seen between CR6 and NCR6 (p < 0.001). Of 10 patients with NCR3, 5 showed CR at 6 months (NCR3/CR6). There was no statistical difference in locoregional recurrence-free survival between CR3 and NCR3/CR6 group (p = 0.990). Conclusion Our data suggest half of patients who did not show CR at 3 months eventually achieved CR at 6 months. Waiting until 6 months after radiotherapy may be appropriate for avoiding additional salvage therapy.
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Yu T, Wee CW, Choi N, Wu HG, Kang HC, Park JM, Kim JI, Kim JH, Kwon TK, Chung EJ. Study design and early result of a phase I study of SABR for early-stage glottic cancer. Laryngoscope 2018; 128:2560-2565. [DOI: 10.1002/lary.27226] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/06/2018] [Accepted: 03/20/2018] [Indexed: 01/08/2023]
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Wee CW, Kang HC, Wu HG, Chie EK, Choi N, Park JM, Kim JI, Huang CM, Wang JY, Ng SY, Goodman KA. Intensity-modulated radiotherapy versus three-dimensional conformal radiotherapy in rectal cancer treated with neoadjuvant concurrent chemoradiation: a meta-analysis and pooled-analysis of acute toxicity. Jpn J Clin Oncol 2018; 48:458-466. [DOI: 10.1093/jjco/hyy029] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Ha B, Cho KH, Moon SH, Lee CG, Keum KC, Kim YS, Wu HG, Kim JH, Ahn YC, Oh D, Noh JM, Lee JH, Kim SH, Kim WT, Oh YT, Kang MK, Kim JH, Kim JY, Cho MJ, Kay CS, Choi JH. The Effect of Hospital Case Volume on Clinical Outcomes in Patients with Nasopharyngeal Carcinoma: A Multi-institutional Retrospective Analysis (KROG-1106). Cancer Res Treat 2018; 51:12-23. [PMID: 29397658 PMCID: PMC6333987 DOI: 10.4143/crt.2017.273] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 02/04/2018] [Indexed: 11/21/2022] Open
Abstract
Purpose The purpose of this study was to investigate the effect of hospital case volume on clinical outcomes in patients with nasopharyngeal carcinoma (NPC). Materials and Methods Data on 1,073 patients with cT1-4N0-3M0 NPC were collected from a multi-institutional retrospective database (KROG 11-06). All patients received definitive radiotherapy (RT) either with three-dimensional-conformal RT (3D-CRT) (n=576) or intensity-modulated RT (IMRT) (n=497). The patients were divided into two groups treated at high volume institution (HVI) (n=750) and low volume institution (LVI) (n=323), defined as patient volume ≥ 10 (median, 13; range, 10 to 18) and < 10 patients per year (median, 3; range, 2 to 6), respectively. Endpoints were overall survival (OS) and loco-regional progression-free survival (LRPFS). Results At a median follow-up of 56.7 months, the outcomes were significantly better in those treated at HVI than at LVI. For the 614 patients of propensity score-matched cohort, 5-year OS and LRPFS were consistently higher in the HVI group than in the LVI group (OS: 78.4% vs. 62.7%, p < 0.001; LRPFS: 86.2% vs. 65.8%, p < 0.001, respectively). According to RT modality, significant difference in 5-year OS was observed in patients receiving 3D-CRT (78.7% for HVI vs. 58.9% for LVI, p < 0.001) and not in those receiving IMRT (77.3% for HVI vs. 75.5% for LVI, p=0.170). Conclusion A significant relationship was observed between HVI and LVI for the clinical outcomes of patients with NPC. However, the difference in outcome becomes insignificant in the IMRT era, probably due to the standardization of practice by education.
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Kim HJ, Kim S, Ha SW, Wu HG. Are Doses to ICRU Reference Points Valuable for Predicting Late Rectal and Bladder Morbidity after Definitive Radiotherapy in Uterine Cervix Cancer? TUMORI JOURNAL 2018; 94:327-32. [DOI: 10.1177/030089160809400307] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aims and Background To evaluate whether doses or dose rates at International Commission on Radiation Units (ICRU) reference points are of value for predicting risks of late rectal and bladder morbidity in patients with uterine cervical cancer who have undergone external beam radiotherapy and intracavitary irradiation. Methods Late rectal complications and late bladder complications were evaluated in 54 patients who were treated by external beam radiotherapy followed by intracavitary irradiation between January 1996 and December 1999. External beam radiotherapy was delivered in 1.8 Gy daily fractions to a whole pelvis dose of 50.4 Gy followed by intracavitary irradiation at total point A doses ranging from 75 Gy to 85 Gy. Intracavitary irradiation was performed with dose rates of 0.5–0.7 Gy/h to point A in most patients, but 8 patients were treated at a higher dose rate (0.83–1.15 Gy/h) to shorten the hospitalization period. Biologically effective doses for the reference points were calculated using a linear quadratic model. Results Grade 3 rectal and bladder morbidity by Radiation Therapy Oncology Group (RTOG) criteria developed in 4 patients (7.4%) and 1 (1.9%), respectively. An age of >60 years (P = 0.01) and a total dose to the rectal reference point of ≥80 Gy (P = 0.03) were found to be correlated with a higher rate of rectal morbidity. Total dose (≥80 Gy), dose rate (≥0.75 Gy/h), and biologically effective doses (≥135 Gy3) at the bladder reference point were found to be significant factors for the development of late bladder morbidity. By multivariate analysis, age was identified as the only significant factor of late rectal complications, and biologically effective doses at the bladder reference point was the only significant factor of late bladder complications. Conclusions RTOG grade 3 late rectal and bladder morbidity developed in respectively 7.4% and 1.9% of the patients. The significant risk factors for late rectal and bladder morbidity were old age and biologically effective doses at the bladder reference point, respectively.
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Park JM, Park SY, Wu HG, Kim JI. Improvement of VMAT plan quality for head and neck cancer with high resolution fluences generated by couch shift between arcs. Phys Med 2018. [PMID: 29519394 DOI: 10.1016/j.ejmp.2018.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
PURPOSE To investigate the changes in quality of the volumetric modulated arc therapy (VMAT) plans with couch-shift between arcs by half of a multi-leaf collimator (MLC) leaf width. METHODS A total of 22 patients with head-and-neck cancer were retrospectively selected. Since the smallest MLC leaf width was 5 mm in this study, the couch was shifted by 2.5 mm in the longitudinal-direction between arcs to increase the resolution of fluence map. A total of three types of VMAT plans were generated for each patient; the three types of plans were a two-full-arc plan without couch-shift (NS plan), a two-half-arc-pair plan with couch-shift (HAS plan), and a two-full-arc pair plan with couch-shift (FAS plan). Changes in the dose-volumetric parameters were investigated. RESULTS The FAS plan showed the best plan quality for the target volumes and organs at risk compared to the NS and HAS plans. However, the magnitudes of differences among the three types of plans were minimal, and every plan was clinically acceptable. The average integral doses of the NS, HAS, and FAS plans were 160,549 ± 37,600 Gy-cc, 147,828 ± 33,343 Gy-cc, and 156,030 ± 36,263 Gy-cc, respectively. The average monitor unit of the NS, HAS, and FAS plans were 717 ± 120 MU, 648 ± 100 MU, and 763 ± 158 MU, respectively. CONCLUSIONS The HAS plan was better than the others in terms of normal tissue sparing and plan efficiency. By shifting the couch by half of the MLC leaf width in the longitudinal direction between arcs, the VMAT plan quality could be improved.
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Wee CW, An HJ, Kang HC, Kim HJ, Wu HG. Variability of Gross Tumor Volume Delineation for Stereotactic Body Radiotherapy of the Lung With Tri- 60Co Magnetic Resonance Image-Guided Radiotherapy System (ViewRay): A Comparative Study With Magnetic Resonance- and Computed Tomography-Based Target Delineation. Technol Cancer Res Treat 2018; 17:1533033818787383. [PMID: 30012039 PMCID: PMC6050807 DOI: 10.1177/1533033818787383] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Introduction: To evaluate the intra-/interobserver variability of gross target volumes between
delineation based on magnetic resonance imaging and computed tomography in patients
simulated for stereotactic body radiotherapy for primary lung cancer and lung
metastasis. Materials and Methods: Twenty-five patients (27 lesions) who underwent computed tomography and magnetic
resonance simulation with the MR-60Co system (ViewRay) were included in the
study. Gross target volumes were delineated on the magnetic resonance imaging
(GTVMR) and computed tomography (GTVCT) images by 2 radiation
oncologists (RO1 and RO2). Volumes of all contours were measured. Levels of
intraobserver (GTVMR_RO vs GTVCT_RO) and interobserver
(GTVMR_RO1 vs GTVMR_RO2; GTVCT_RO1 vs
GTVCT_RO2) agreement were evaluated using the generalized κ statistics and
the paired t test. Results: No significant volumetric difference was observed between all 4 comparisons
(GTVMR_RO1 vs GTVCT_RO1, GTVMR_RO2 vs
GTVCT_RO2, GTVMR_RO1 vs GTVMR_RO2, and
GTVCT_RO1 vs GTVCT_RO2; P > .05), with mean
volumes of GTVs ranging 5 to 6 cm3. The levels of agreement between those 4
comparisons were all substantial with mean κ values of 0.64, 0.66, 0.74, and 0.63,
respectively. However, the interobserver agreement level was significantly higher for
GTVCT compared to GTVMR (P <.001). The mean
κ values significantly increased in all 4 comparisons for tumors >5 cm3
compared to tumors ≤5 cm3 (all P < .05). Conclusion: No significant differences in volumes between magnetic resonance- and computed
tomograpghy-based Gross target volumes were found among 2 ROs. Magnetic resonance-based
GTV delineation for lung stereotactic body radiotherapy also demonstrated acceptable
interobserver agreement. Tumors >5 cm3 show higher intra-/interobserver
agreement compared to tumors <5 cm3. More experience should be accumulated
to reduce variability in magnetic resonance-based Gross target volumes delineation in
lung stereotactic body radiotherapy.
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Lee YG, Lee E, Bang SM, Kang C, Kim Y, Kim H, Wu HG, Kim Y, Kim T, Lee KW, Lee SH, Kim DW, Heo D, Kim I. Risk factors and prognostic impact of venous thromboembolism in Asian patients with non-small cell lung cancer. Thromb Haemost 2017; 111:1112-20. [DOI: 10.1160/th13-11-0956] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Accepted: 01/19/2014] [Indexed: 12/21/2022]
Abstract
SummaryAlthough the overall risk of venous thromboembolism (VTE) is high in patients with non-small cell lung cancer (NSCLC), risk identification is limited. The goal of this study was to estimate the incidence, risk factors and prognostic implications of VTE, and to evaluate a genetic link between oncogenes and the risk of VTE in Asian patients with NSCLC. A total of 1,998 consecutive patients with NSCLC were enrolled and analysed retrospectively. Since the effects of therapeutics on VTE development were modified by stage, stratified analyses were performed. When comparing overall survival in terms of VTE development, a propensity score-matching method was adopted to minimise potential confounding. The six-month and two-year cumulative incidences of VTE were 4.2% and 6.4%, respectively. The risk of VTE increased 2.45-fold with each advancing stage in NSCLC (p<0.001). The independent predictors of VTE were advanced age, pneumonectomy and palliative radiotherapy in localised NSCLC and ineligibility for surgery and palliative radiotherapy in locally advanced NSCLC. Adenocarcinoma histology (vs squamous cell) and former/current smoking status were significant predictors of VTE in metastatic NSCLC. A significant association between VTE and decreased survival was observed only among patients with localised NSCLC. EGFR mutations (p=0.170) and ALK rearrangements (p=0.159) were not associated with VTE development in lung adenocarcinoma. In conclusion, the two-year cumulative incidence of VTE is 6.4% in Asian patient with NSCLC. The significant predictors of VTE are different across stages of NSCLC. The prognostic impact of VTE on poor survival was limited to localised NSCLC.
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Park JM, Shin KH, Kim JI, Park SY, Jeon SH, Choi N, Kim JH, Wu HG. Air–electron stream interactions during magnetic resonance IGRT. Strahlenther Onkol 2017; 194:50-59. [DOI: 10.1007/s00066-017-1212-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Accepted: 08/30/2017] [Indexed: 10/18/2022]
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Song S, Wu HG, Lee CG, Keum KC, Kim MS, Ahn YC, Oh D, Park HJ, Lee SW, Park G, Moon SH, Cho KH, Kim YS, Won Y, Oh YT, Kim WT, Jeong JU. Chemoradiotherapy versus surgery followed by postoperative radiotherapy in tonsil cancer: Korean Radiation Oncology Group (KROG) study. BMC Cancer 2017; 17:598. [PMID: 28854890 PMCID: PMC5577763 DOI: 10.1186/s12885-017-3571-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 08/21/2017] [Indexed: 11/12/2022] Open
Abstract
Background Treatment of tonsil cancer, a subset of oropahryngeal cancer, varies between surgery and radiotherapy. Well-designed studies in tonsil cancer have been rare and it is still controversial which treatment is optimal. This study aimed to assess the outcome and failure patterns in tonsil cancer patients treated with either approaches. Methods We retrospectively reviewed medical records of 586 patients with tonsil cancer, treated between 1998 and 2010 at 16 hospitals in Korea. Two hundred and one patients received radiotherapy and chemotherapy (CRT), while 385 patients received surgery followed by radiotherapy and/or chemotherapy (SRT). Compared with the SRT group, patients receiving CRT were older, with more advanced T stage and received higher radiotherapy dose given by intensity modulation techniques. Overall survival (OS), disease-free survival (DFS), locoregional recurrence-free survival (LRRFS), distant metastasis-free survival (DMFS), and clinicopathologic factors were analyzed. Results At follow-up, the 5-year OS, DFS, LRRFS and DMFS rates in the CRT group were 82, 78, 89, and 94%, respectively, and in the SRT group were 81, 73, 87, and 89%, respectively. Old age, current smoking, poor performance status, advanced T stage, nodal involvement, and induction chemotherapy were associated with poor OS. Induction chemotherapy had a negative prognostic impact on OS in both treatment groups (p = 0.001 and p = 0.033 in the CRT and SRT groups, respectively). Conclusions In our multicenter, retrospective study of tonsil cancer patients, the combined use of radiotherapy and chemotherapy resulted in comparable oncologic outcome to surgery followed by postoperative radiotherapy, despite higher-risk patients having been treated with the definitive radiotherapy. Induction chemotherapy approaches combined with either surgery or definitive radiotherapy were associated with unfavorable outcomes. Electronic supplementary material The online version of this article (10.1186/s12885-017-3571-3) contains supplementary material, which is available to authorized users.
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Kim JI, Lee H, Wu HG, Chie EK, Kang HC, Park JM. Development of patient-controlled respiratory gating system based on visual guidance for magnetic-resonance image-guided radiation therapy. Med Phys 2017; 44:4838-4846. [PMID: 28675492 DOI: 10.1002/mp.12447] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/04/2017] [Accepted: 06/26/2017] [Indexed: 12/25/2022] Open
Abstract
PURPOSE The aim of this study is to develop a visual guidance patient-controlled (VG-PC) respiratory gating system for respiratory-gated magnetic-resonance image-guided radiation therapy (MR-IGRT) and to evaluate the performance of the developed system. METHODS The near-real-time cine planar MR image of a patient acquired during treatment was transmitted to a beam projector in the treatment room through an optical fiber cable. The beam projector projected the cine MR images inside the bore of the ViewRay system in order to be visible to a patient during treatment. With this visual information, patients voluntarily controlled their respiration to put the target volume into the gating boundary (gating window). The effect of the presence of the beam projector in the treatment room on the image quality of the MRI was investigated by evaluating the signal-to-noise ratio (SNR), uniformity, low-contrast detectability, high-contrast spatial resolution, and spatial integrity with the VG-PC gating system. To evaluate the performance of the developed system, we applied the VG-PC gating system to a total of seven patients; six patients received stereotactic ablative radiotherapy (SABR) and one patient received conventional fractionated radiation therapy. RESULTS The projected cine MR images were visible even when the room light was on. No image data loss or additional time delay during delivery of image data were observed. Every indicator representing MRI quality, including SNR, uniformity, low-contrast detectability, high-contrast spatial resolution, and spatial integrity exhibited values higher than the tolerance levels of the manufacturer with the VG-PC gating system; therefore, the presence of the VG-PC gating system in the treatment room did not degrade the MR image quality. The average beam-off times due to respiratory gating with and without the VG-PC gating system were 830.3 ± 278.2 s and 1264.2 ± 302.1 s respectively (P = 0.005). Consequently, the total treatment times excluding the time for patient setup with and without the VG-PC gating system were 1453.3 ± 297.3 s and 1887.2 ± 469.6 s, respectively, on average (P = 0.005). The average number of beam-off events during whole treatment session was reduced from 457 ± 154 times to 195 ± 90 times by using the VG-PC gating system (P < 0.001). CONCLUSIONS The developed system could improve treatment efficiency when performing respiratory-gated MR-IGRT. The VG-PC gating system could be applied to any kind of bore-type radiotherapy machine.
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Jeon SH, Shin KH, Park SY, Kim JI, Park JM, Kim JH, Chie EK, Wu HG. Seroma change during magnetic resonance imaging-guided partial breast irradiation and its clinical implications. Radiat Oncol 2017. [PMID: 28633637 PMCID: PMC5477744 DOI: 10.1186/s13014-017-0843-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Background To investigate the patterns of post-lumpectomy seroma volume (SV) change and related clinical factors to determine the benefits of adaptive planning in magnetic resonance imaging (MRI)-guided partial breast irradiation (PBI). Methods MRI data obtained from 37 women with early breast cancer acquired at simulation and at the 1st, 6th, and 10th fractions were analyzed. The planning target volume (PTV) was defined as unequal margins of 10–15 mm added according to the directional surgical margin status of each seroma. Treatment was performed using a 0.35 T MRI-guided radiotherapy system. Univariate analysis was performed to assess the correlations between SV change rate and clinical factors. Seroma and PTV for adaptive planning were based on the images obtained at the 6th fraction. Results The average time intervals between surgery-simulation, simulation-1st, 1st-6th, and 6th-10th fractions were 23.1, 8.5, 7.2, and 5.9 days, respectively. Of the 37 patients, 33 exhibited decreased SV over the treatment period. The mean SV of these 33 patients decreased from 100% at simulation to 60, 48, and 40% at each MRI scan. In most cases (26/33), the logarithm of SV was inversely proportional to the elapsed time from surgery (R2 > 0.90, Pearson’s correlation test). The volume of spared normal tissue from adaptive radiotherapy was proportional to the absolute change in SV (R2 = 0.89, Pearson’s correlation test). Conclusion Seromas exhibit exponential shrinkage over the course of PBI. In patients receiving PBI, frequent monitoring of SV could be helpful in decision-making regarding adaptive planning, especially those with a large seroma.
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Ock CY, Kim S, Keam B, Kim S, Ahn YO, Chung EJ, Kim JH, Kim TM, Kwon SK, Jeon YK, Jung KC, Kim DW, Wu HG, Sung MW, Heo DS. Changes in programmed death-ligand 1 expression during cisplatin treatment in patients with head and neck squamous cell carcinoma. Oncotarget 2017; 8:97920-97927. [PMID: 29228662 PMCID: PMC5716702 DOI: 10.18632/oncotarget.18542] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 06/04/2017] [Indexed: 12/31/2022] Open
Abstract
Programmed death-ligand 1 (PD-L1) expression is regarded as a predictive marker for anti-PD-1/PD-L1 therapy. The purpose of study was to explore the changes in PD-L1 expression in head and neck squamous cell carcinoma (HNSCC) during treatment. Paired HNSCC tissues prior to and after cisplatin-based treatment were evaluated to determine PD-L1 protein expression by immunohistochemistry. Among the 35 HNSCC patient samples, PD-L1 expression status changed after treatment in 37.1% (13/35) of samples. Among the 13 patients whose baseline PD-L1 was negative, PD-L1 expression was increased in 9 cases (69.2%) and remained negative in 4 cases (30.8%, P = 0.003). Patients exposed to cisplatin generally showed PD-L1 up-regulation (83.3%, P = 0.037) compared to those not exposed to cisplatin (57.1%, P = 0.072). To validate these findings in vitro, changes in PD-L1 expression in HNSCC cell lines (Detroit-562, PCI-13, SNU-1041, SNU-1066, SNU-1076, and FaDu) were analyzed by western blotting and flow cytometry after treatment with cisplatin and interferon-gamma. In HNSCC cell lines, PD-L1 expression was significantly up-regulated after cisplatin, along with phosphor-MAPK/ERK kinase up-regulation. In conclusion, PD-L1 expression in HNSCC may be altered during cisplatin treatment, activating the MAPK/ERK kinase pathway.
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Kim Y, Cho KH, Moon SH, Lee CG, Keum KC, Lee SW, Ahn YC, Oh D, Kim YS, Won YK, Wu HG, Hah JH, Oh YT. Comparison of the Clinical Outcomes of Patients with Squamous Cell Carcinoma of the Tonsil Receiving Postoperative Ipsilateral Versus Bilateral Neck Radiotherapy: A Propensity Score Matching Analysis (KROG 11-07). Cancer Res Treat 2017; 49:1097-1105. [PMID: 28183163 PMCID: PMC5654171 DOI: 10.4143/crt.2016.425] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Accepted: 01/23/2017] [Indexed: 01/17/2023] Open
Abstract
Purpose The impact of postoperative ipsilateral neck radiotherapy (INRT) versus bilateral neck radiotherapy (BNRT) on the clinical outcomes of patients with tonsillar squamous cell carcinoma was analyzed retrospectively. Materials and Methods Between October 2001 and June 2012, 241 patients with T1-2 and N0-N2b tonsillar carcinoma from 16 institutes underwent postoperative INRT (n=84) or BNRT (n=157) following a tonsillectomy. Seventy patients were identified from each group by propensity score matching and compared in terms of the overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS) rates calculated using the Kaplan-Meier method with a log-rank test. Results The median follow-up was 55 months (range, 3 to 133 months). The survival outcomes in the INRT and BNRT groups were similar: 5-year OS (92.8% vs. 94.0%, p=0.985), DFS (80.5% vs. 94.2%. p=0.085), LRRFS (88.1% vs. 97.1%, p=0.083), and DMFS (92.7% vs. 97.0%, p=0.370). Subgroup analysis revealed no contralateral neck recurrence in 61 patients with T1-2N0-2a regardless of the treatment groups. For 79 patients with N2b, contralateral neck recurrence was more common in the INRT group than in the BNRT group (7.9% vs. 0.0%), but the difference was not significant (p=0.107). The overall grade ≥ 2 toxicities were lower in the INRT group: acute (45.7% vs. 74.3%, p=0.001) and late (4.3% vs. 31.4%, p < 0.001), respectively. Conclusion INRT is an attractive strategy for patients with T1-2N0-2a tonsillar carcinoma compared to BNRT. For patients with N2b, there was a small risk of contralateral neck recurrence when treated with INRT, but its impact on the OS was limited with successful salvage treatment.
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Jang BS, Kim HJ, Kim BH, Kim DW, Kim YT, Kim YW, Jang MJ, Wu HG. Clinical outcomes of stereotactic ablative radiotherapy in patients with pulmonary metastasis. Jpn J Clin Oncol 2017; 47:61-66. [PMID: 28122893 DOI: 10.1093/jjco/hyw147] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/08/2016] [Accepted: 09/09/2016] [Indexed: 12/27/2022] Open
Abstract
BACKGROUNDS In addition to its curative use for early stage lung cancer, stereotactic ablative radiotherapy is also indicated for pulmonary metastatic disease. Aims of this study were to retrospectively analyze treatment outcomes and to find prognostic factors for survivals. METHODS Treatment outcomes and toxicities of 85 cases of SABR in 72 patients were retrospectively reviewed from September 2012 to April 2015. Prognostic factors were analyzed using Cox proportional hazards regression. RESULTS The local failure-free survival rate at 2 years was 98%. Of the case, 1-year and 2-year progression-free survival rates were 62% and 48%, and overall survival rates were 90% and 72%, respectively. Multivariate analyses demonstrated that controlled primary cancer (P = 0.01), absence of extra-pulmonary metastatic disease (P < 0.01) and disease-free interval longer than 1 year (P < 0.01) favorably affected progression-free survival. Furthermore, the absence of extra-pulmonary metastatic disease (P < 0.01) increased overall survival as well. Grade 1 or 2 radiation pneumonitis was found in 37 cases, and Grade 1 chest wall pain was found in 1 case. CONCLUSIONS Stereotactic ablative radiotherapy demonstrated good local control with tolerable adverse effects for pulmonary metastasis. The presence or absence of extra-pulmonary metastasis was found to be prognostic factor of mortality after stereotactic ablative radiotherapy treatment.
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Sim JA, Chang YJ, Shin A, Noh DY, Han W, Yang HK, Kim YW, Kim YT, Jeong SY, Yoon JH, Kim YJ, Heo D, Kim TY, Oh DY, Wu HG, Kim HJ, Chie EK, Kang KW, Kim JH, Yun YH. Perceived needs for the information communication technology (ICT)-based personalized health management program, and its association with information provision, health-related quality of life (HRQOL), and decisional conflict in cancer patients. Psychooncology 2017; 26:1810-1817. [PMID: 28054737 DOI: 10.1002/pon.4367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 12/29/2016] [Accepted: 12/30/2016] [Indexed: 11/12/2022]
Abstract
OBJECTIVE The use of information communication technology (ICT)-based tailored health management program can have significant health impacts for cancer patients. Information provision, health-related quality of life (HRQOL), and decision conflicts were analyzed for their relationship with need for an ICT-based personalized health management program in Korean cancer survivors. METHODS The health program needs of 625 cancer survivors from two Korean hospitals were analyzed in this cross-sectional study. Multivariate logistic regression was used to identify factors related to the need for an ICT-based tailored health management system. Association of the highest such need with medical information experience, HRQOL, and decision conflicts was determined. Furthermore, patient intentions and expectations for a web- or smartphone-based tailored health management program were investigated. RESULTS Cancer survivors indicated high personalized health management program needs. Patients reporting the highest need included those with higher income (adjusted odds ratio [aOR], 1.70; 95% [confidence interval] CI, 1.10-2.63), those who had received enough information regarding helping themselves (aOR, 1.71; 95% CI, 1.09-2.66), and those who wished to receive more information (aOR, 1.59; 95% CI, 0.97-2.61). Participants with cognitive functioning problems (aOR, 2.87; 95%CI, 1.34-6.17) or appetite loss (aOR, 1.77; 95% CI, 1.07-2.93) indicated need for a tailored health care program. Patients who perceived greater support from the decision-making process also showed the highest need for an ICT-based program (aOR, 0.49; 95% CI, 0.30-0.82). CONCLUSIONS We found that higher income, information provision experience, problematic HRQOL, and decisional conflicts are significantly associated with the need for an ICT-based tailored self-management program.
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Lim YJ, Chang JH, Kim HJ, Keam B, Kim TM, Kim DW, Paeng JC, Kang KW, Chung JK, Jeon YK, Chung DH, Wu HG. Superior Treatment Response and In-field Tumor Control in Epidermal Growth Factor Receptor-mutant Genotype of Stage III Nonsquamous Non-Small cell Lung Cancer Undergoing Definitive Concurrent Chemoradiotherapy. Clin Lung Cancer 2016; 18:e169-e178. [PMID: 28131636 DOI: 10.1016/j.cllc.2016.12.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Revised: 12/20/2016] [Accepted: 12/20/2016] [Indexed: 10/20/2022]
Abstract
BACKGROUND Although previous in vitro data have suggested a more radio-sensitive nature of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC) cell lines, the clinical behavior according to the EGFR mutational status has not been well-established. In this study, we performed a comparative outcome analysis of EGFR-mutant and wild-type locally advanced NSCLC with chemoradiotherapy (CRT). PATIENTS AND METHODS A total of 102 patients with stage III nonsquamous NSCLC undergoing primary CRT were identified. Clinicopathologic characteristics, including the degree of glucose uptake, were evaluated. Failure patterns considering the radiation field and survival outcomes were compared according to the EGFR mutational status. RESULTS Pre- and post-CRT maximum standardized uptake values were significantly lower in EGFR-mutant tumors (P = .010 and .018, respectively). The overall response rate was higher in the EGFR-mutant group compared with the wild-type (89% vs. 64%, respectively; P = .023). The 3-year overall survival rate was better with the genetic alteration (68.0% vs. 47.4%, P = .046), but the statistical significance did not remain in multivariate analysis (hazard ratio, 0.68; 95% confidence interval, 0.30-1.55). Considering the tumor progression inside or outside the radiation field, the EGFR-mutant group showed longer in-field time to progression (P = .002), even after adjusting for other related baseline variables (hazard ratio, 0.27; 95% confidence interval, 0.11-0.71). CONCLUSION The differential metabolic activity, failure patterns, and prognosis suggest the distinct nature of the EGFR-mutant tumors. EGFR mutational status needs to be considered for more precise curative-intent treatment strategies of locally advanced nonsquamous NSCLC.
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Kwon J, Kim DH, Park JM, Park YH, Hwang YH, Wu HG, Shin KH, Kim IA. Targeting Phosphatidylinositol 4-Kinase IIIα for Radiosensitization: A Potential Model of Drug Repositioning Using an Anti-Hepatitis C Viral Agent. Int J Radiat Oncol Biol Phys 2016; 96:867-876. [DOI: 10.1016/j.ijrobp.2016.08.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2016] [Revised: 08/05/2016] [Accepted: 08/10/2016] [Indexed: 12/13/2022]
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Park JM, Park SY, Kim HJ, Wu HG, Carlson J, Kim JI. A comparative planning study for lung SABR between tri-Co-60 magnetic resonance image guided radiation therapy system and volumetric modulated arc therapy. Radiother Oncol 2016; 120:279-85. [PMID: 27401404 DOI: 10.1016/j.radonc.2016.06.013] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/14/2016] [Accepted: 06/19/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND AND PURPOSE To compare the plan quality of tri-(60)Co magnetic-resonance image-guided radiation therapy (IGRT) to that of volumetric modulated arc therapy (VMAT) for lung stereotactic ablative radiotherapy (SABR). MATERIALS AND METHODS A total of 22 patients with lung tumors located in the lower lobe were selected retrospectively. For each patient, VMAT plans with linac and intensity-modulated radiation therapy (IMRT) plans with the tri-(60)Co system were generated with prescription doses of 60Gy (daily dose=15Gy). For both plan types, identical CT image sets and structures were used, with the exception of planning target volumes (PTV). The PTV for VMAT was generated from the internal target volume (ITV) while the PTV for the tri-(60)Co system was generated from the gross tumor volume (GTV). Clinically relevant dose-volumetric parameters were calculated and analyzed. RESULTS The average PTV volumes of tri-(60)Co plans and VMAT plans were 10.5±12.3cc vs. 27.2±23.5cc, respectively (p<0.001). The maximum and mean doses to PTVs were 64.0±2.6Gy vs. 62.5±0.9Gy (p=0.005) and 61.4±1.7Gy vs. 60.0±0.5Gy (p<0.001), respectively. The conformity and homogeneity indices were 1.89±0.38 vs. 1.01±0.40 (p<0.001) and 0.06±0.02 vs. 0.04±0.00 (p<0.001), respectively. No considerable differences for organs at risk (OARs) were observed between tri-(60)Co plans and VMAT plans. In terms of target conformity, integral dose and lung mean dose, the plan quality of tri-(60)Co plans was inferior to that of VMAT plans when the PTV volumes of tri-(60)Co plans were less than 10cc. However, all treatment plans of tri-(60)Co system were clinically acceptable. CONCLUSION For lung SABR, the quality of ITV-based VMAT plans was better than that of GTV-based tri-(60)Co plans especially when the PTV volumes of the tri-(60)Co plans were less than 10cc. If the breathing pattern of a patient is reproducible, VMAT is considered the optimal option for lung SABR, otherwise the tri-(60)Co IGRT should be considered due to the ability to monitor tumor motion during treatment.
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Yoo SH, Ock CY, Keam B, Kim TM, Kim JH, Jeon YK, Chung EJ, Kwon SK, Hah JH, Kwon TK, Kim DW, Wu HG, Sung MW, Heo DS. Poor prognostic factors in human papilloma virus-positive head and neck cancer: Who should not be candidate of de-escalated treatment? J Clin Oncol 2016. [DOI: 10.1200/jco.2016.34.15_suppl.6078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Ock CY, Keam B, Kim TM, Han DH, Won TB, Lee SH, Hah JH, Kwon TK, Kim DW, Kim DY, Rhee CS, Wu HG, Sung MW, Heo DS. Induction chemotherapy in head and neck squamous cell carcinoma of the paranasal sinus and nasal cavity: a role in organ preservation. Korean J Intern Med 2016; 31:570-8. [PMID: 26976150 PMCID: PMC4855097 DOI: 10.3904/kjim.2015.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 04/30/2015] [Accepted: 05/12/2015] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND/AIMS The role of induction chemotherapy (IC) for eyeball preservation has not been established in head and neck squamous cell carcinoma (HNSCC) of the paranasal sinus and nasal cavity (PNSNC). Periorbital involvement frequently leads to eyeball exenteration with a margin of safety. We evaluated the treatment outcomes, including survival and eyeball preservation, of patients who received IC for HNSCC of the PNSNC. METHODS We reviewed 21 patients diagnosed with HNSCC of the PNSNC who were treated with IC. We analyzed response, eyeball preservation rate, and overall survival. RESULTS Tumors were located in the paranasal sinus (n = 14) or nasal cavity (n = 7). Most patients had stage T4a (n = 10) or T4b (n = 7) disease. More than half of the patients received a chemotherapy regimen of docetaxel, fluorouracil, and cisplatin (n = 11). Thirteen patients (61.9%) achieved a partial response after IC and 15 patients (71.4%) achieved T down-staging. Among 17 patients with stage T4 disease, which confers a high risk of orbital exenteration, 14 (82.4%) achieved preservation of the involved eye. The 3-year overall survival (OS) rate of patients who achieved a partial response to IC was 84.6%. The 3-year OS rate of patients with stable disease or disease progression after IC was 25.0% (p = 0.038). CONCLUSIONS IC could be considered for down-staging patients with advanced T-stage disease. It could also be a reasonable option for eyeball preservation in locally advanced HNSCC of the PNSNC.
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