• Journal of Gastric Cancer
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• v.14 no.4
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• pp.259-265
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• 2014

Purpose: Survival analysis of gastric cancer patients requires knowledge about factors that affect survival time. This paper attempted to analyze the survival of patients with incomplete registered data by using imputation methods. Materials and Methods: Three missing data imputation methods, including regression, expectation maximization algorithm, and multiple imputation (MI) using Monte Carlo Markov Chain methods, were applied to the data of cancer patients referred to the cancer institute at Imam Khomeini Hospital in Tehran in 2003 to 2008. The data included demographic variables, survival times, and censored variable of 471 patients with gastric cancer. After using imputation methods to account for missing covariate data, the data were analyzed using a Cox regression model and the results were compared. Results: The mean patient survival time after diagnosis was $49.1{\pm}4.4$ months. In the complete case analysis, which used information from 100 of the 471 patients, very wide and uninformative confidence intervals were obtained for the chemotherapy and surgery hazard ratios (HRs). However, after imputation, the maximum confidence interval widths for the chemotherapy and surgery HRs were 8.470 and 0.806, respectively. The minimum width corresponded with MI. Furthermore, the minimum Bayesian and Akaike information criteria values correlated with MI (-821.236 and -827.866, respectively). Conclusions: Missing value imputation increased the estimate precision and accuracy. In addition, MI yielded better results when compared with the expectation maximization algorithm and regression simple imputation methods.

• Journal of Gastric Cancer
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• v.16 no.3
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• pp.161-166
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• 2016

Purpose: Lymph node (LN) metastasis is the best prognostic indicator in non-distant metastatic advanced gastric cancer. This study aimed to assess the prognostic value of various clinicopathologic factors in node-negative advanced gastric cancer. Materials and Methods: We retrospectively analyzed the clinical records of 254 patients with primary node-negative stage T2~4 gastric cancer. These patients were selected from a pool of 1,890 patients who underwent radical resection at Memorial Jin-Pok Kim Korea Gastric Cancer Center, Inje University Seoul Paik Hospital between 1998 and 2008. Results: Of the 254 patients, 128 patients (50.4%), 88 patients (34.6%), 37 patients (14.6%), and 1 patient (0.4%) had T2, T3, T4a, and T4b tumors, respectively. In a univariate analysis, operation type, T-stage, venous invasion, tumor size, and less than 15 LNs significantly correlated with tumor recurrence and cumulative overall survival. In a multivariate logistic regression analysis, tumor size, venous invasion, and less than 15 LNs significantly and independently correlated with recurrence. In a multivariate Cox proportional hazards analysis, tumor size (hazard ratio [HR]: 2.926; 95% confidence interval [CI]: 1.173~7.300; P=0.021), venous invasion (HR: 3.985; 95% CI: 1.401~11.338; P=0.010), and less than 15 LNs (HR: 0.092; 95% CI: 0.029~0.290; P<0.001) significantly correlated with overall survival. Conclusions: Node-negative gastric cancers recurred in 8.3% of the patients in our study. Tumor size, venous invasion, and less than 15 LNs reliably predicted recurrence as well as survival. Aggressive postoperative treatments and timely follow-ups should be considered in cases with these characteristics.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6595-6597
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• 2015

Objective: To investigate short- and long-term treatment effects and side reactions of lobaplatin plus 5-Fu combined and concurrent radiotherapy in treating patients with inoperable middle-advanced stage esophageal cancer. Methods: Sixty patients with middle-advanced stage esophageal squamous cell cancer were retrospectively analyzed. All patients were administered lobaplatin (50 mg intravenously) for 2 h on day 1, and 5-Fu ($500mg/m^2$) injected intravenously from day 1 to 5 for 1 cycle, in an interval of 21 days for totally 4 cycles. At the same time, late-course accelerated hyperfractionated three-dimensional conformal radiotherapy was performed. Patients were firstly treated with conventional fractionated irradiation (1.8 Gy/d, 5 times/week, a total of 23 treatments, and DT41.4 Gy), and then treated with accelerated hyperfractionated irradiation (1.5 Gy, 2 times/d, a total of 27 Gy in 9 days, an entire course of 6-7 weeks, and DT 68.4Gy). Results: All patients completed treatment, including 10 complete response (CR), 41 partial response (PR), 7 stable disease (SD), and 2 progressive disease (PD). The total effective rate was 85.0% (51/60). Thirty-nine patients had an increased KPS score. One-, 2-, and 3-year survival rates were 85.3%, 57.5%, and 41.7%, respectively. The median survival time was 27 months. The adverse reactions included myelosuppression, which was mainly degree I and II. The occurrence rate of radiation esophagitis was 17.5%. No significant hepatic or renal toxicity was observed. Conclusion: Lobaplatin plus 5-Fu combined with concurrent radiotherapy is safe and effective in treating patients with middle-advanced stage esophageal cancer. However, this result warrants further evaluation by randomized clinical studies.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4001-4005
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• 2012

Backgrouds: The hedgehog (Hh) signaling pathway is composed of patched (PTCH) and smoothened (SMO), two transmembrane proteins, and downstream glioma-associated oncogene homolog (Gli) transcription factors. Hh signaling plays a pathological role in the occurrence and development of various cancers. Methods: To investigate the expression of SMO protein in colon cancer and its association with clinicopathological parameters and postoperative liver metastasis, immunohistochemistry was performed with paraffin-embedded specimens of 96 cases. Relationships between SMO protein expression and clinicopathological parameters, postoperative liver metastasis were analyzed. Results: IHC examination showed that SMO protein expression was significantly increased in colon cancer tissues compared to normal colon tissues (P = 0.042), positively related to lymph node metastases (P = 0.018) and higher T stages (P = 0.026). Postoperative live metastasis-free survival was significantly longer in the low SMO expression group than in those with high SMO expression ($48.7{\pm}8.02$ months vs $28.0{\pm}6.86$ months, P=0.036). Multivariate analysis showed SMO expression level to be an independent prognostic factor for postoperative live metastasis-free survival (95% confidence interval [CI] =1.46-2.82, P = 0.008). Conclusions: Our results suggest that in patients with colon cancer, the SMO expression level is an independent biomarker for postoperative liver metastasis, and SMO might play an important role in colon cancer progression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.17
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• pp.7413-7417
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• 2014

Background: Development of gastric cancer (GC) is a multistep process that requires alterations in the expression of oncogenes and tumor suppressor genes, occurring over several decades. The p53 tumor suppressor protein is involved in cell-cycle control, apoptosis and DNA repair. One of the most important regulators of p53 is MDM2, which acts as a negative regulator in the p53 pathway. Based on the key role of p53 and MDM2 in tumor suppression, polymorphisms that cause change in their function might affect cancer risk. We therefore elevated associations of the polymorphisms of p53 (R72P) and MDM2 (SNP309) with GC in Iran. Materials and Methods: A total of 104 patients with gastric cancer and 100 controls were recruited. Genomic DNA was extracted from fresh gastric samples. Genotyping of the p53 and MDM2 genes was performed using allele specific PCR (AS-PCR). Results: There was no significant difference between the p53 codon 72 polymorphism distribution in control and patient groups (p=0.54), but the G allele of MDM2 was found to be over-represented in patients (p=0. 01, Odds Ratio=2. 08, 95% Confidence Interval= 1.37-4.34). Conclusions: The p53 R72P seems not to be a potential risk factor for development of GC among Iranian patients, but our data suggest that MDM2 SNP309 might modify the risk related to GC.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3241-3245
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• 2015

Purpose: To examine the effectiveness of mitomycin-C and chemo-hyperthermia in combination for patients with high-risk non-muscle-invasive bladder cancer. Materials and Methods: Between November 2011-September 2013, 43 patients with high-risk non-muscle-invasive bladder cancer undergoing adjuvant chemo-hyperthermia in two centers were evaluated retrospectively. Treatment consisted of 6 weekly sessions, followed by 6 sessions. Recurrence and progression rate, recurrence-free interval and side effects were examined. Analyzed factors included age, gender, smoking status, AB0 blood group, body mass index, T stage and grade, concominant CIS assets. The associations between predictors and recurrence were assessed using multivariate Cox proportional hazard analyses. Results: A total of 40 patients completed induction therapy. Thirteen (32.5%) were diagnosed with tumor recurrence. Median follow-up was 30 months (range 9-39). Median recurrence-free survival was 23 months (range 6-36). The Kaplan-Meier-estimated recurrence-free rates for the entire group at 12 and 24 months were 82% and 61%. There was no statistically significant difference between patient subgroups. Cox hazard analyses showed that an A blood type (OR=6.23, p=0.031) was an independent predictor of recurrence-free. Adverse effects were seen in 53% of patients and these were frequently grades 1 and 2. Conclusions: Intravesical therapy with combination of mitomycin-C and chemohyperthermia seems to be appropriate in high-risk patients with non-muscle-invasive bladder cancer who cannot tolerate or have contraindications for standard BCG therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.869-874
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• 2015

Background: The prognostic value of microvessel density (MVD), reflecting angiogenesis, detected in ovarian cancer is currently controversial. Here we performed a meta-analysis of all relevant eligible studies. Materials and Methods: A comprehensive search of online PubMed, Medline, EMBASE and Sciencedirect was performed to identify all related articles. The search strategy was designed as 'microvessel density', 'ovarian cancer', 'ovarian neoplasm', 'CD34' and 'angiogenesis'. Results: The studies were categorized by author/year, number of patients, FIGO stage, histology, cutoff value for microvessel density, types of survival analysis, methods of hazard rations (HR) estimation, HR and its 95% confidence interval (CI). Combined hazard ratios suggested that high MVD was associated with poor overall survival (OS) and progression-free survival (PFS), with HR and 95% CIs of 1.84 (1.33-2.35) and 1.36 (1.06-1.66), respectively. Subgroup analysis showed that high MVD detected by CD34 was relevant for OS [HR=1.67 (1.36-2.35)], but not MVD detected with other antibodies [HR=2.11 (0.90-3.31)]. Another subgroup analysis indicated that high MVD in patients without pre-chemotherapy, but not with pre-chemotherapy, was associated with OS [HR=1.88(1.59-2.18 and HR=1.70 (-0.18-3.59)]. Conclusions: The OS and PFS with high MVD were significant poorer than with low MVD in ovarian cancer patients. However, high MVD detected by CD34 seems to be more associated with survival for patients without pre-chemotherapy.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.803-805
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• 2014

The IL-16 rs4778889 T/C polymorphism is associated with cancer risk. However, the results are conflicting. We performed this meta-analysis to derive a more precise estimation of the relationship. A comprehensive literature search was performed using PubMed, Embase and Web of Science databases. Odds ratio (OR) and 95% confidence interval (CI) were used to assess the strength of association. A total of 6 studies including 1,603 cases and 2,342 controls were identified. With all studies involved, results showed no statistically significant association between IL-16 rs4778889 T/C polymorphism and cancer risk (CC vs. CT+TT: OR=0.74, 95%CI:0.55-1.02, $P_h=0.15$; CC+CT vs. TT: OR=0.89, 95%CI: 0.72-1.10, $P_h=0.03$; CC vs. TT: OR=0.73, 95%CI: 0.53-1.00, $P_h=0.08$; CT vs. TT: OR=0.91, 95%CI: 0.79-1.05, $P_h=0.08$; C vs. T: OR=0.89, 95%CI: 0.74-1.07, $P_h=0.02$). In addition, the results were not changed when studies were stratified by cancer type. However, to verify our findings, it is essential to perform more well-designed studies with larger sample sizes in the future.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3455-3458
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• 2016

Osteosarcoma is a common primary malignant bone tumor in children and adolescents. Recent worldwide average incidences of osteosarcoma in people aged 0 to 24 years were 4.3 and 3.4 per million, respectively, with a ratio of 1.4:1. However, data on the incidence of osteosarcoma in Thailand are limited. This study analyzed the incidence of osteosarcoma in the upper northern region of Thailand, with a population of 5.85 million people (8.9% of the total Thai population), using data for the years 1998 to 2012, obtained from the Chiang Mai Cancer Registry (CMCR) at Chiang Mai University Hospital and the Lampang Cancer Registry (LCR) at the Lampang Cancer Hospital, a total of 144 cases. The overall annual incidence of osteosarcoma was 1.67 per million with a male:female ratio of 1.36:1. Incidences by age group (male and female) at 0 to 24, 25 to 59 and over 60 years were 3.5 (3.9 and 3.0), 0.8 (0.9 and 0.6), and 0.7 (0.8 and 0.5), respectively. The peak incidence occurred at 15 to 19 years for males and at 10 to 14 years for females. The median survival time was 18 months with a 5-year survival rate of 43%. Neither the age group nor the 5-year interval period of treatment was significantly correlated with survival during the 15-year period studied.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.825-828
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• 2013

Objective: The objective of this study was to determine the five-year survival among patients with cervical cancer treated in Hospital Universiti Sains Malaysia. Methods: One hundred and twenty cervical cancer patients diagnosed between $1^{st}$ July 1995 and $30^{th}$ June 2007 were identified. Data were obtained from medical records. The survival probability was determined using the Kaplan-Meier method and the log-rank test was applied to compare the survival distribution between groups. Results: The overall five-year survival was 39.7% [95%CI (Confidence Interval): 30.7, 51.3] with a median survival time of 40.8 (95%CI: 34.0, 62.0) months. The log-rank test showed that there were survival differences between the groups for the following variables: stage at diagnosis (p=0.005); and primary treatment (p=0.0242). Patients who were diagnosed at the latest stage (III-IV) were found to have the lowest survival, 18.4% (95%CI: 6.75, 50.1), compared to stage I and II where the five-year survival was 54.7% (95%CI: 38.7, 77.2) and 40.8% (95%CI: 27.7, 60.3), respectively. The five-year survival was higher in patients who received surgery [52.6% (95%CI: 37.5, 73.6)] as a primary treatment compared to the non-surgical group [33.3% (95%CI: 22.9, 48.4)]. Conclusion: The five-year survival of cervical cancer patients in this study was low. The survival of those diagnosed at an advanced stage was low compared to early stages. In addition, those who underwent surgery had higher survival than those who had no surgery for primary treatment.