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Purpose@#The benefit of adjuvant chemotherapy following curative-intent surgery in pancreatic ductal adenocarcinoma (PDAC) patients who had received neoadjuvant FOLFIRINOX is unclear. This study aimed to assess the survival benefit of adjuvant chemotherapy in this patient population. @*Materials and Methods@#This retrospective study included 218 patients with localized non-metastatic PDAC who received neoadjuvant FOLFIRINOX and underwent curative-intent surgery (R0 or R1) between January 2017 and December 2020. The association of adjuvant chemotherapy with disease-free survival (DFS) and overall survival (OS) was evaluated in overall patients and in the propensity score matched (PSM) cohort. Subgroup analysis was conducted according to the pathology-proven lymph node status. @*Results@#Adjuvant chemotherapy was administered to 149 patients (68.3%). In the overall cohort, the adjuvant chemotherapy group had significantly improved DFS and OS compared to the observation group (DFS: median, 13.8 months [95% confidence interval (CI), 11.0 to 19.1] vs. 8.2 months [95% CI, 6.5 to 12.0]; p < 0.001; and OS: median, 38.0 months [95% CI, 32.2 to not assessable] vs. 25.7 months [95% CI, 18.3 to not assessable]; p=0.005). In the PSM cohort of 57 matched pairs of patients, DFS and OS were better in the adjuvant chemotherapy group than in the observation group (p < 0.001 and p=0.038, respectively). In the multivariate analysis, adjuvant chemotherapy was a significant favorable prognostic factor (vs. observation; DFS: hazard ratio [HR], 0.51 [95% CI, 0.36 to 0.71; p < 0.001]; OS: HR, 0.45 [95% CI, 0.29 to 0.71; p < 0.001]). @*Conclusion@#Among PDAC patients who underwent surgery following neoadjuvant FOLFIRINOX, adjuvant chemotherapy may be associated with improved survival. Randomized studies should be conducted to validate this finding.
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Purpose@#This study was designed to determine the feasibility of preoperative chemoradiotherapy (PCRT) in patients with clinical T2N0 distal rectal cancer. @*Methods@#Patients who underwent surgery for clinical T2N0 distal rectal cancer between January 2008 and December 2016 were included. Patients were divided into PCRT and non-PCRT groups. Non-PCRT patients underwent radical resection or local excision (LE) according to the surgeon’s decision, and PCRT patients underwent surgery according to the response to PCRT. Patients received 50.0 to 50.4 gray of preoperative radiotherapy with concurrent chemotherapy. @*Results@#Of 127 patients enrolled, 46 underwent PCRT and 81 did not. The mean distance of lesions from the anal verge was lower in the PCRT group (P=0.004). The most frequent operation was transanal excision and ultralow anterior resection in the PCRT and non-PCRT groups, respectively. Of the 46 patients who underwent PCRT, 21 (45.7%) achieved pathologic complete response, including 15 of the 24 (62.5%) who underwent LE. Rectal sparing rate was significantly higher in the PCRT group (11.1% vs. 52.2%, P<0.001). There were no significant differences in 3- and 5-year overall survival and recurrence-free survival regardless of PCRT or surgical procedures. @*Conclusion@#PCRT in clinical T2N0 distal rectal cancer patients increased the rectal sparing rate via LE and showed acceptable oncologic outcomes. PCRT may be a feasible therapeutic option to avoid abdominoperineal resection in clinical T2N0 distal rectal cancer.
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Purpose@#The aim of this study was (1) to compare the reverse engineering technique with other existing measurement methods and (2) to analyze the effect of implant angulations and impression coping types on implant impression accuracy with reverse engineering technique. @*Materials and methods@#Three different master models were fabricated and the distance between the two implant center points in parallel master model was measured with different three methods; digital caliper measurement (Group DC), optical measuring (Group OM), and reverse engineering technique (Group RE). The 90 experimental models were fabricated with three types of impression copings for the three different implant angulation and the angular and distance error rate were calculated. One-way ANOVA was used for comparison among the evaluation methods (P .05). The standard deviations in reverse engineering were much lower than those of digital caliper and optical measurement. Hybrid groups had no significant difference from the pick-up groups in distance error rates (P > .05). @*Conclusion@#The reverse engineering technique demonstrated its potential as an evaluation technique of 3D accuracy of impression techniques.
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Purpose@#The purpose of this pilot study is to evaluate the reliability and validity of the Korean version of the oral health impact profile (OHIP-EDENT K) for edentulous patients. @*Materials and Methods@#The study was conducted on 12 patients who fabricated overdenture in the Department of Prosthodontics, Korea University, Guro Hospital. All subjects completed the Korean version of Oral Health Impact Profile (OHIP K) questionnaire. Shorten version of the OHIP called OHIP-14 K and OHIP-EDENT K were derived from the datasets. Cronbach's alpha was used to measure internal consistency of the summary scores for OHIP-EDENT K. The Spearman's correlation coefficient between the summary scores for OHIP-EDENT K and OHIP K was calculated to evaluate concurrent validity. @*Results@#The reliability of the summary scores for OHIP-EDENT K was acceptable (α=.736). The Spearman's correlation coefficient of the summary scores for OHIP-EDENT K and OHIP K was 0.966, which was statistically significant (P<.001). OHIP-EDENT K exhibited less susceptibility to floor effects than OHIP-14 K and appeared to measure change as effectively as OHIP K. In order to prove the reliability, responsiveness and validity of OHIP-EDENT K, further studies with more samples are needed. @*Conclusion@#The OHIP-EDENT K, a questionnaire on oral health-related QOL comprising 19 items, has measurement properties comparable with the full 49-item version. This modified shortened version can be an alternative questionnaire to full version of OHIP K and OHIP-14 K in edentulous patients.
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Purpose@#To investigate the safety and efficacy of hypofractionated radiation therapy (HFRT) in patients with non-small cell lung cancer who are unfit for surgery or stereotactic body radiation therapy (SBRT) at our institution. @*Materials and Methods@#From May 2007 to December 2018, HFRT was used to treat 68 lesions in 64 patients who were unsuitable for SBRT because of central tumor location, large tumor size, or contiguity with the chest wall. The HFRT schedule included a dose of 50–70 Gy delivered in 10 fractions over 2 weeks. The primary outcome was freedom from local progression (FFLP), and the secondary endpoints included overall survival (OS), disease-free survival, and toxicities. @*Results@#The median follow-up period was 25.5 months (range, 5.3 to 119.9 months). The FFLP rates were 79.8% and 67.8% at 1 and 2 years, respectively. The OS rates were 82.8% and 64.1% at 1 and 2 years, respectively. A larger planning target volume was associated with lower FFLP (p = 0.023). Dose escalation was not associated with FFLP (p = 0.964). Four patients (6.3%) experienced grade 3–5 pulmonary toxicities. Tumor location, central or peripheral, was not associated with either grade 3 or higher toxicity. @*Conclusion@#HFRT with 50–70 Gy in 10 fractions demonstrated acceptable toxicity; however, the local control rate can be improved compared with the results of SBRT. More studies are required in patients who are unfit for SBRT to investigate the optimal fractionation scheme.
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Some patients who have undergone preoperative chemoradiotherapy (CRT) following surgery have been diagnosed with late recurrence more than 5 years after treatment, raising questions about the possible benefit extending surveillance beyond the recommended 5 years. In 2011, a 71-year-old male patient was diagnosed with T3N+ low-lying rectal cancer located 3 cm from the anal verge before undergoing long-course preoperative CRT. After CRT, the patient was reexamined and diagnosed with ycT1–2N0 lesion, so local excision (LE) was performed. The patient underwent intensive surveillance for up to 5 years, and no evidence of recurrence was found. At 74 months after surgery, the patient was hospitalized for a hematochezia, and local recurrence at the excision site and peritoneal seeding nodules were identified. Considering the late recurrence in this patient, it might be necessary to long-term follow-up beyond 5 years in patients with preoperative CRT followed by LE.
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Purpose@#The aim of this study was (1) to compare the reverse engineering technique with other existing measurement methods and (2) to analyze the effect of implant angulations and impression coping types on implant impression accuracy with reverse engineering technique. @*Materials and methods@#Three different master models were fabricated and the distance between the two implant center points in parallel master model was measured with different three methods; digital caliper measurement (Group DC), optical measuring (Group OM), and reverse engineering technique (Group RE). The 90 experimental models were fabricated with three types of impression copings for the three different implant angulation and the angular and distance error rate were calculated. One-way ANOVA was used for comparison among the evaluation methods (P .05). The standard deviations in reverse engineering were much lower than those of digital caliper and optical measurement. Hybrid groups had no significant difference from the pick-up groups in distance error rates (P > .05). @*Conclusion@#The reverse engineering technique demonstrated its potential as an evaluation technique of 3D accuracy of impression techniques.
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Purpose@#The purpose of this pilot study is to evaluate the reliability and validity of the Korean version of the oral health impact profile (OHIP-EDENT K) for edentulous patients. @*Materials and Methods@#The study was conducted on 12 patients who fabricated overdenture in the Department of Prosthodontics, Korea University, Guro Hospital. All subjects completed the Korean version of Oral Health Impact Profile (OHIP K) questionnaire. Shorten version of the OHIP called OHIP-14 K and OHIP-EDENT K were derived from the datasets. Cronbach's alpha was used to measure internal consistency of the summary scores for OHIP-EDENT K. The Spearman's correlation coefficient between the summary scores for OHIP-EDENT K and OHIP K was calculated to evaluate concurrent validity. @*Results@#The reliability of the summary scores for OHIP-EDENT K was acceptable (α=.736). The Spearman's correlation coefficient of the summary scores for OHIP-EDENT K and OHIP K was 0.966, which was statistically significant (P<.001). OHIP-EDENT K exhibited less susceptibility to floor effects than OHIP-14 K and appeared to measure change as effectively as OHIP K. In order to prove the reliability, responsiveness and validity of OHIP-EDENT K, further studies with more samples are needed. @*Conclusion@#The OHIP-EDENT K, a questionnaire on oral health-related QOL comprising 19 items, has measurement properties comparable with the full 49-item version. This modified shortened version can be an alternative questionnaire to full version of OHIP K and OHIP-14 K in edentulous patients.
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Purpose@#To investigate the safety and efficacy of hypofractionated radiation therapy (HFRT) in patients with non-small cell lung cancer who are unfit for surgery or stereotactic body radiation therapy (SBRT) at our institution. @*Materials and Methods@#From May 2007 to December 2018, HFRT was used to treat 68 lesions in 64 patients who were unsuitable for SBRT because of central tumor location, large tumor size, or contiguity with the chest wall. The HFRT schedule included a dose of 50–70 Gy delivered in 10 fractions over 2 weeks. The primary outcome was freedom from local progression (FFLP), and the secondary endpoints included overall survival (OS), disease-free survival, and toxicities. @*Results@#The median follow-up period was 25.5 months (range, 5.3 to 119.9 months). The FFLP rates were 79.8% and 67.8% at 1 and 2 years, respectively. The OS rates were 82.8% and 64.1% at 1 and 2 years, respectively. A larger planning target volume was associated with lower FFLP (p = 0.023). Dose escalation was not associated with FFLP (p = 0.964). Four patients (6.3%) experienced grade 3–5 pulmonary toxicities. Tumor location, central or peripheral, was not associated with either grade 3 or higher toxicity. @*Conclusion@#HFRT with 50–70 Gy in 10 fractions demonstrated acceptable toxicity; however, the local control rate can be improved compared with the results of SBRT. More studies are required in patients who are unfit for SBRT to investigate the optimal fractionation scheme.
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Some patients who have undergone preoperative chemoradiotherapy (CRT) following surgery have been diagnosed with late recurrence more than 5 years after treatment, raising questions about the possible benefit extending surveillance beyond the recommended 5 years. In 2011, a 71-year-old male patient was diagnosed with T3N+ low-lying rectal cancer located 3 cm from the anal verge before undergoing long-course preoperative CRT. After CRT, the patient was reexamined and diagnosed with ycT1–2N0 lesion, so local excision (LE) was performed. The patient underwent intensive surveillance for up to 5 years, and no evidence of recurrence was found. At 74 months after surgery, the patient was hospitalized for a hematochezia, and local recurrence at the excision site and peritoneal seeding nodules were identified. Considering the late recurrence in this patient, it might be necessary to long-term follow-up beyond 5 years in patients with preoperative CRT followed by LE.
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PURPOSE@#. The purpose of this in vitro study was to examine the reliability of the Anycheck device and the effect of the healing abutment diameter on the Anycheck values (implant stability test, IST). @*MATERIALS AND METHODS@#. Thirty implants were placed into three artificial bone blocks with 10 Ncm, 15 Ncm, and 35 Ncm insertion torque value (ITV), respectively (n = 10). (1) The implant stability was measured with three different kinds of devices (Periotest M, Osstell ISQ Mentor, and Anycheck). (2) Five different diameters (4.0, 4.5, 4.8, 5.5, and 6.0 mm) of healing abutments of the same height were connected to the implants and the implant stability was measured four times in different directions with Anycheck. The measured mean values were statistically analyzed. @*RESULTS@#. The correlation coefficient between the mean implant stability quotient (ISQ) and IST value was 0.981 (P<.01) and the correlation coefficient between the meant periotest value (PTV) and IST value was -0.931 (P<.01). There were no statistically significant differences among the IST values with different healing abutment diameters. @*CONCLUSION@#. There was a strong correlation between the Periotest M and Anycheck values and between the ISQ and IST. The diameter of the healing abutment had no effect on the Anycheck values.
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Purpose@#To analyze the clinical outcomes and long-term toxicity of pediatric patients with Hodgkin lymphoma after combined-modality treatment (CMT) with involved-field or involved-nodal radiotherapy (RT). @*Materials and Methods@#We retrospectively reviewed the records of 27 pediatric Hodgkin lymphoma patients who received CMT at a single institution between January 1990 and July 2017. Patients with stage I–III received a heterogeneous chemotherapy regimen depending on their risk group followed by 19.8–36 Gy RT, with the dose based on their response to the chemotherapy before RT. An optional 9–20 Gy boost was delivered to residual sites. The risk group was determined based on the initial stage, the presence of bulky disease, and any B symptoms. We evaluated overall survival, event-free survival, and long-term toxicities. @*Results@#A total of 27 patients completed the CMT. At a median follow-up of 125 months (range, 9 to 337 months), the estimated 5-year event-free survival and overall survival were 88.9% and 96.3%, respectively. Late symptomatic cardiopulmonary toxicity was not observed, and only one patient was positive on a subclinical obstructive pulmonary function test. The incidence of hypothyroidism was 58.3% among 12 patients with an available thyroid function test. There was one papillary thyroid cancer diagnosed 7.2 years after treatment. @*Conclusion@#CMT for pediatric Hodgkin lymphoma with involved-field and involved-nodal RT achieved an excellent survival with only modest long-term toxicity. Smaller-field RT seemed to decrease long-term toxicities and had good local control.
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Purpose@#Since the introduction of nab-paclitaxel plus gemcitabine (nab-P+GEM) as first-line (1L) treatment for metastatic pancreatic adenocarcinoma (mPDAC), optimal second-line (2L) chemotherapy after progression is unclear. We assessed clinical outcomes of 2L chemotherapy for disease that progressed on 1L nab-P+GEM. @*Materials and Methods@#Among the 203 patients previously treated with 1L nab-P+GEM for mPDAC at Asan Medical Center, between February and December 2016, records of 120 patients receiving 2L chemotherapy after progression on nab-P+GEM were retrospectively reviewed. The response rate and survival were evaluated along with analysis of prognostic factors. @*Results@#Fluoropyrimidine-oxaliplatin doublets (FOLFOX or XELOX) were used in 78 patients (65.0%), fluoropyrimidine monotherapy in 37 (30.8%), and liposomal irinotecan plus fluorouracil in two (1.7%). The median progression-free survival (PFS) and overall survival (OS) were 3.29 months and 7.33 months from the start of 2L therapy. Fluoropyrimidine-oxaliplatin regimens and fluoropyrimidine monotherapy did not yield significantly different median PFS (2.89 months vs. 3.81 months, p=0.40) or OS (7.04 months vs. 7.43 months, p=0.86). A high neutrophil-lymphocyte ratio (> 2.2) and a short time to progression with 1L nab-P+GEM (< 6.4 months) were independent prognostic factors of poor OS with 2L therapy. @*Conclusion@#2L fluoropyrimidine-oxaliplatin doublets and fluoropyrimidine monotherapy after failure of 1L nab-P+GEM had modest efficacy, with no differences in treatment outcomes between them. Further investigation is warranted for the optimal 2L chemo-regimens and sequencing of systemic chemotherapy for patients with mPDAC.
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Purpose@#The current standard chemotherapy for advanced biliary tract cancer (BTC) has limited benefit,and novel therapies need to be investigated. @*Materials and Methods@#In this prospective cohort study, programmed death ligand-1 (PD-L1)–positive BTC patientswho progressed on first-line gemcitabine plus cisplatin were enrolled. Pembrolizumab 200mg was administered intravenously every 3 weeks. @*Results@#Between May 2018 and February 2019, 40 patients were enrolled. Pembrolizumab wasgiven as second-line (47.5%) or third-line therapy (52.5%). The objective response ratewas 10% and 12.5% by Response Evaluation Criteria in Solid Tumor (RECIST) v1.1 andimmune-modified RECIST (imRECIST) and median duration of response was 6.3 months.Among patients with progressive disease as best response, one patient (1/20, 5.0%)achieved complete response subsequently. The median progression-free survival (PFS) andoverall survival (OS) were 1.5 months (95% confidence interval [CI], 0.0 to 3.0) and 4.3months (95% CI, 3.5 to 5.1), respectively, and objective response per imRECIST was significantlyassociated with PFS (p < 0.001) and OS (p=0.001). Tumor proportion score 50%was significantly associated with higher response rates including the response after pseudoprogression(vs. < 50%; 37.5% vs. 6.5%; p=0.049). @*Conclusion@#Pembrolizumab showed modest anti-tumor activity in heavily pretreated PD-L1–positiveBTC patients. In patients who showed objective response, durable response could beachieved.
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PURPOSE: The rare incidence of isolated para-aortic lymph node (PALN) recurrence of colorectal cancer has precluded the formulation of treatment guidelines. This study evaluated and compared the effects of different treatment modalities on survival outcomes in patients with PALN recurrence.METHODS: Patients diagnosed with isolated PALN recurrence after curative resection for primary colorectal cancer from January 2004 to December 2014 were evaluated retrospectively. Patients with isolated recurrence were selected using imaging modalities. Overall survival (OS) and survival after recurrence (SAR) were analyzed and compared between different treatments using the Kaplan-Meier method.RESULTS: The median OS was 64 months with a median follow-up time of 50 months. Of the 46 patients with PALN recurrence, 35 (76.1%) had isolated recurrences. Of these 35 patients, 16 underwent PALN resection and 19 received chemotherapy. Median SAR was significantly longer in patients who did than did not undergo resection (71 months vs. 39 months, P = 0.017). Median OS tended to be longer in patients who did than did not undergo resection (77 months vs. 62 months, P = 0.055). SAR was similar in patients who received radiotherapy and those who underwent resection (34 months vs. 46 months, P = 0.146). Three of 16 patients (18.8%) who underwent resection were found to be recurrence-free.CONCLUSION: Surgical resection of isolated PALN recurrence may benefit patients, with favorable survival outcomes and by providing definitive diagnosis for proper treatment planning.
Subject(s)
Humans , Colorectal Neoplasms , Diagnosis , Drug Therapy , Follow-Up Studies , Incidence , Lymph Node Excision , Lymph Nodes , Methods , Mortality , Radiotherapy , Recurrence , Retrospective StudiesABSTRACT
PURPOSE: Current neoadjuvant chemotherapy (NAC) may enable therapies such as surgical resection and local ablation of metastases in patients with colorectal liver metastasis (CLM). We evaluated outcomes in CLM patients who underwent resection and/or local treatment after NAC and identified prognostic factors for oncologic outcomes. METHODS: Patients who received NAC followed by resection and/or local treatment of hepatic metastasis from 2013 to 2015 were included. Treatment and tumor-related variables were tabulated. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using the Kaplan-Meier method. Cox regression analysis was used to identify factors associated with RFS and OS. RESULTS: Sixty-eight patients received NAC followed by resection and/or local treatment of hepatic metastases. Targeted therapy was administered in 50% of the patients. RFS was 35.8% at 1 year and 19.4% at 2 years postoperatively. OS was 95.6% at 1 year and 88.2% at 2 years postoperatively. In the multivariable analysis, R1 resection margin (hazard ratio [HR], 3.95; P = 0.008) of the liver metastases and ypN1/ypN2 (HR, 2.356 and 1.983, respectively; P = 0.041) were associated with poor RFS. Both factors were also significantly related to OS. CONCLUSION: Resection margin of the metastatic tumor and ypN status are the only relevant factors for RFS and OS in CLM patients treated with NAC. Despite early and high rates of recurrence, CLM patients treated with NAC who undergo resection and/or local treatment have acceptable OS. Multidisciplinary review of candidates for surgery and cautious planning are crucial for achieving optimal outcomes.
Subject(s)
Humans , Colorectal Neoplasms , Drug Therapy , Liver , Methods , Neoplasm Metastasis , RecurrenceABSTRACT
PURPOSE: The aim of this study is to evaluate the effects of various primers on the microtensile bond strength (µTBS) of resin cements to cobalt-chromium (Co-Cr) dental casting alloy. MATERIALS AND METHODS: Four adhesive primers (Universal primer, Metal primer II, Alloy primer, and Metal/Zirconia primer) and two resin cements (Panavia F2.0, G-CEM LinkAce) were tested. One hundred fifty Co-Cr beams were prepared from Co-Cr ingots via casting (6 mm length × 1 mm width × 1 mm thick). The metal beams were randomly divided into ten groups according to the adhesive primers and resin cements used; the no-primer groups served as the control (n = 15). After sandblasting with aluminum oxide (125 µm grain), the metal and resin cements were bonded together using a silicone mold. Prior to testing, all metal-resin beams were examined under stereomicroscope, and subjected to the µTBS test. The mean value of each group was analyzed via one-way ANOVA with Tukey's test as post hoc (α = .05) using SPSS software. RESULTS: The mean µTBS of all groups was ranged from 20 to 28 MPa. There is no statistically significant difference between groups (P > .05). Mixed failure, which is the combination of adhesive and cohesive failures, is the most prevalent failure mode in both the Panavia F2.0 and G-Cem LinkAce groups. CONCLUSION: The µTBS of all tested groups are relatively high; however, the primers used in this study result in no favorable effect in the µTBS of Panavia F2.0 and G-Cem LinkAce resin cement to Co-Cr alloy.
Subject(s)
Adhesives , Alloys , Aluminum Oxide , Fungi , Resin Cements , Silicon , SiliconesABSTRACT
PURPOSE: To investigate the patterns of recurrence in patients with neuroblastoma treated with radiation therapy to the primary tumor site. MATERIALS AND METHODS: We retrospectively analyzed patients with high-risk neuroblastoma managed with definitive treatment with radiation therapy to the primary tumor site between January 2003 and June 2017. These patients underwent three-dimensional conformal radiation therapy or intensity-modulated radiation therapy. A total of 14–36 Gy was delivered to the planning target volume, which included the primary tumor bed and the selected metastatic site. The disease stage was determined according to the International Neuroblastoma Staging System (INSS). We evaluated the recurrence pattern (i.e., local or systemic), progression-free survival, and overall survival. RESULTS: A total of 40 patients with high-risk neuroblastoma were included in this study. The median patient age was 4 years (range, 1 to 11 years). Thirty patients (75%) had INSS stage 4 neuroblastoma. At the median follow-up of 58 months, there were 6 cases of local recurrence and 10 cases of systemic recurrence. Among the 6 local failure cases, 4 relapsed adjacent to the radiation field. The other 2 relapsed in the radiation field (i.e., para-aortic and retroperitoneal areas). The main sites of distant metastasis were the bone, lymph nodes, and bone marrow. The 5-year progression-free survival was 70.9% and the 5-year overall survival was 74.3%. CONCLUSION: Radiation therapy directed at the primary tumor site provides good local control. It seems to be adequate for disease control in patients with high-risk neuroblastoma after chemotherapy and surgical resection.
Subject(s)
Humans , Bone Marrow , Disease-Free Survival , Drug Therapy , Follow-Up Studies , Lymph Nodes , Neoplasm Metastasis , Neuroblastoma , Radiotherapy , Recurrence , Retrospective StudiesABSTRACT
PURPOSE: This study evaluated the effect of nonthermal plasma treatment on the bond strength of autopolymerizing relining resin to the injection molded thermoplastic denture base resins (TDBRs) with different surface treatments. MATERIALS AND METHODS: Acrylic Resin (Acrytone), Polyester (Estheshot-Bright), Polyamide (Valplast) and Polypropylene (Weldenz) were subjected to various surface treatments: No treatment, Nonthermal plasma, Sandblasting, Sandblasting and nonthermal plasma. Specimens were bonded using an autopolymerizing relining resin. Shear bond strength was tested using universal testing machine with crosshead speed of 1 mm/min. Statistical analysis by two-way analysis of variance with Tukey's test post hoc was used. RESULTS: Acrytone showed significantly higher shear bond strength value among other TDBR group while Weldenz had the lowest. The sandblasting and nonthermal plasma condition had significantly higher shear bond strength value in all of the resin groups (P < .05). CONCLUSION: The use of nonthermal plasma treatment showed limited effect on the shear bond strength between TDBRs and relining resin, and combination of nonthermal plasma and sandblasting improved the shear bond strength between TDBR and reline material.
Subject(s)
Denture Bases , Dentures , Fungi , Nylons , Plasma , Polyesters , PolypropylenesABSTRACT
PURPOSE: Pancreatic cancer associated double primary tumors are rare and their clinicopathologic characteristics are not well elucidated. MATERIALS AND METHODS: Clinicopathologic factors of 1,352 primary pancreatic cancers with or without associated double primary tumors were evaluated. RESULTS: Of resected primary pancreatic cancers, 113 (8.4%) had associated double primary tumors, including 26 stomach, 25 colorectal, 18 lung, and 13 thyroid cancers. The median interval between the diagnoses of pancreatic cancer and associated double primary tumors was 0.5 months. Overall survival (OS) of pancreatic cancer patients with associated double primary tumors was longer than those with pancreatic cancer only (median, 23.1 months vs. 17.0 months; p=0.002). Patients whose pancreatic cancers were resected before the diagnosis of metachronous tumors had a better OS than patients whose pancreatic cancer resected after the diagnosis of metachronous tumors (48.9 months and 13.5 months, p=0.001) or those whose pancreatic cancers were resected synchronously with non-pancreas tumors (19.1 months, p=0.043). The OS of pancreatic cancer patients with stomach (33.9 months, p=0.032) and thyroid (117.8 months, p=0.049) cancers was significantly better than those with pancreas cancer only (17.0 months). CONCLUSION: About 8% of resected pancreatic cancers had associated double primary tumors, and those from the colorectum, stomach, lung, and thyroid were common. Patients whose pancreatic cancer was resected before the diagnosis of metachronous tumors had better OS than those resected after the diagnosis of metachronous tumors or those resected synchronously.