Ching-Chieh Yang

Validity of the Age-Adjusted Charlson Comorbidity Index on Clinical Outcomes for Patients with Nasopharyngeal Cancer Post Radiation Treatment: A 5-Year Nationwide Cohort Study

Purpose To characterize the impact of comorbidity on survival outcomes for patients with nasopharyngeal carcinoma (NPC) post radiotherapy (RT). Methods A total of 4095 patients with NPC treated by RT or RT plus chemotherapy (CT) in the period from 2007 to 2011 were included through Taiwan’s National Health Insurance Research Database. Information on comorbidity present prior to the NPC diagnosis was obtained and adapted to the Charlson Comorbidity Index (CCI), Age-Adjusted Charlson Comorbidity Index (ACCI) and a revised head and neck comorbidity index (HN-CCI). The prevalence of comorbidity and the influence on survival were calculated and analyzed. Results Most of the patients (75%) were male (age 51±13 years) and 2470 of them (60%) had at least one comorbid condition. The most common comorbid condition was diabetes mellitus. According to these three different comorbidity index (CCI, ACCI and HN-CCI), higher scores were associated with worse overall survival (P< 0.001). The Receiver Operating Characteristic (ROC) curve was used to assess the discriminating ability of CCI, AACI and HN-CCI scores and it demonstrated the predictive ability for mortality with the ACCI (0.693, 95% CI 0.670–0.715) was superior to that of the CCI (0.619, 95% CI 0.593–0.644) and HN-CCI (0.545, 95%CI 0.519–0.570). Conclusion Comorbidities greatly influenced the clinical presentations, therapeutic interventions, and outcomes of patients with NPC post RT. Higher comorbidity index scores accurately was associated with worse survival. The ACCI seems to be a more appropriate prognostic indicator and should be considered in further clinical studies.

Incorporation of log odds of positive lymph nodes into the AJCC TNM classification improves prediction of survival in oral cancer

To assess the prognostic performance of a new N classification that incorporates the log odds of positive lymph nodes (LODDS) into the routinely used pathological N classification for oral squamous cell carcinoma (OSCC) patients.

Prognostic Performance of a New Staging Category to Improve Discrimination of Disease-Specific Survival in Nonmetastatic Oral Cancer.

Importance Inflammatory status is associated with outcome in oral squamous cell carcinoma (OSCC). Combining the preoperative neutrophil to lymphocyte ratio (NLR) and histopathologic features may provide clinicians with more exact information regarding the prognosis of OSCC. Objective To compare the prognostic performance of the routinely used pathologic TNM staging with a new staging category that incorporates the NLR and histopathologic features. Design, Setting, and Participants This retrospective cohort study included 396 patients with newly diagnosed OSCC who underwent major surgery at a medical center from January 1, 2006, through December 31, 2013. Follow-up was completed on October 31, 2015, and data analysis was performed from January 1, 2016, through April 30, 2016. Main Outcomes and Measures The multivariate Cox proportional hazards regression model was used to determine the clinical or pathologic factors associated with 5-year disease-specific survival (DSS), and these factors were assigned integer points to create a new staging category. The monotonicity and discriminatory ability of the pathologic TNM staging and new staging category were evaluated with the linear trend &khgr;2 test, Akaike information criterion, and Harrell C statistic. Results In total, 396 patients who underwent major surgery with curative intent for OSCC with or without adjuvant therapy were included in this study (mean [SD] age, 53 [11] years; 367 men [92.7%] and 29 women [7.3%]). Perineural invasion (adjusted hazard ratio [aHR], 1.74; 95% CI, 1.23-2.46), high NLR (aHR, 1.60; 95% CI, 1.11-2.30), advanced pT (T3 + T4) classification (aHR, 1.59; 95% CI, 1.13-2.25), and advanced pN (N2) classification (aHR, 3.96; 95% CI, 2.78-5.63) were independent prognostic survival factors. The &bgr; coefficients from the Cox proportional hazards regression model were used to develop an integer-based weighted point system (perineural invasion, score of 1; NLR, score of 1; advanced pT, score of 1; and advanced pN, score of 3). The summations of these risk scores were stratified for the new staging category as follows: new stage I, score of 0; new stage II, score of 1; new stage III, score of 2 or 3; and new stage IV, score of 4 to 6. Compared with the American Joint Committee on Cancer staging category, this new staging category provided better monotonicity with a higher linear trend &khgr;2 value (106 vs 49), better discriminatory ability with smaller Akaike information criterion (1497 vs 1533), and greater Harrell C statistic (0.73 vs 0.69) for 5-year DSS. The results remained robust after adjusting other risk factors. Conclusions and Relevance In this study, new staging category had better DSS discriminatory ability and could help to identify high-risk patients for intense adjuvant therapy.

Comparison of different comorbidity measures for oral cancer patients with surgical intervention: A longitudinal study from a single cancer center

OBJECTIVE Several comorbid measures have been developed and demonstrated the predictive ability for cancer mortality. We conducted a retrospective study on oral squamous cell carcinoma (OSCC) patients to compare the Charlson comorbidity index score (CCIS) to the Elixhauser comorbidity index score (ECIS). METHODS Newly diagnosed OSCC patients (n=232) post major surgery with or without adjuvant therapy were identified from the cancer registry database between 2006 and 2011. Comorbidities present prior to the cancer diagnosis were obtained and adapted to the CCIS and ECIS. The prevalence of comorbid conditions and the influence on disease-specific survival (DSS) rate were calculated and analyzed by Cox regression model. The discriminatory ability of these two comorbid measures was evaluated by using the adjusted hazard ratio and Akaike information criterion (AIC) in a multivariate regression model. The prediction accuracy was assessed using Harrells c-statistic. RESULTS Most of the patients (93.5%) were male with a mean age of 54 ± 11 years and 77 of them (33.1%) had at least one comorbid condition. The ECIS was associated DSS, with an additional 10% increased risk observed for mortality for each increased score (HR, 1.10; 95% confidence interval [CI], 1.03-1.18) after adjusting with pathological risk features. However, the CCIS was not an independent prognostic factor for these patients. The ECIS increased discriminatory ability but the CCIS did not improve discrimination. CONCLUSIONS Comorbid conditions significantly influenced the clinical outcomes of patient with OSCC post major surgery. A higher ECIS was associated with worse disease specific survival indicative of a valuable prognostic indicator. The ECIS may be considered in further clinical trials for a variety of cancers, including head and neck cancers.

Factors predict prolonged wait time and longer duration of radiotherapy in patients with nasopharyngeal carcinoma: a multilevel analysis.

Purpose Radiotherapy with or without chemotherapy is the primary treatment for patients with nasopharyngeal carcinoma (NPC). It wastes time from diagnosis to treatment. Treatment time of radiotherapy generally takes at least seven weeks. The current study aimed to evaluate factors associated with prolonged wait time and longer duration of radiotherapy in NPC patients. Methods and Materials From Taiwans National Health Insurance research database, we identified 3,605 NPC patients treated with radiotherapy between 2008 and 2011. Wait time was calculated from the date of diagnosis to the start of radiotherapy. The impact of each variable on wait time and duration of radiotherapy was examined by multilevel analysis using a random-intercept model. Results The mean wait time and duration of radiotherapy were 1.78±3.33 and 9.72±7.27 weeks, respectively. Multilevel analysis revealed prolonged wait time in patients aged 45–65 years, those receiving radiotherapy alone, those with more comorbidities, those with low SES, and those living in eastern Taiwan. A prolonged duration of radiotherapy was associated with receipt of concurrent chemoradiotherapy, more comorbidities, and moderate SES. Conclusions Understanding the factors associated with longer wait times and duration of radiotherapy in patients with NPC may help healthcare providers better assist both these patients and potentially those with other head-and-neck cancers.

The study of GaAsInGaAs δ-doping resonant interband tunneling diode

The δ-doping InGaAs/GaAs quantum well resonant interband tunneling diode by low pressure metal organic chemical vapor deposition has been successfully grown. The full width at half maximum of the doping profile analyzed by capacitance-voltage measurement is small. Two kinds of δ-doping resonant interband tunneling diodes were simulated in this study. One was the δn + -i-δp + resonant interband tunneling structure and the other was the δn + -i-δp + -i-δn + single barrier resonant interband tunneling structure. The simulated current-voltage characteristics exhibited the expected N-shaped negative differential resistance. The calculated peak-to-valley current ratio (PVCR) values of δn + -i-δp + and δn + -i-δp + -i-δn + structures are 6 and 5.6, respectively. The calculated PVCR value is larger than experimental PVCR values for the δn + -i-δp + structure. The PVCR values of this study are better than the published data of other authors.

Recommendation for incorporation of a different lymph node scoring system in future AJCC N category for oral cancer

To compare the prognostic value of 3 different lymph node scoring systems “ log odds of positive nodes (LODDS), lymph node ratio (rN), and lymph node yield “ in an effort to improve the staging of oral cancer. We identified 3958 oral cancer patients from Surveillance, Epidemiology, and End Results database from 2007 to 2013. In univariate analysis, LODDS, pN, rN, and lymph node yield were prognostic factors for 5-year disease-specific survival (DSS) and overall survival (OS). Multivariate analysis indicated that patients with LODDS 4 had worst 5-year DSS and OS. Stage migration occurred in pN1 and pN2 patients with LODDS 4. In pN1 patients, those with LODDS 4 had the worst 5-year DSS (41.2%) and OS (31.6%) than patients with pN1 and LODDS 2–3. In pN2 patients, those with LODDS4 had the worst 5-year DSS (34.5%) and OS (27.4%) than patients with pN2 and LODDS 2–3. The proposed staging system, which incorporates LODDS with AJCC pN, had better discriminability and prediction accuracy for predicting survival. We also noted that patients with LODDS 4 given adjuvant radiotherapy had better 5-year DSS and OS. The LODDS should be considered as a future candidate measurement for N category in oral cancer.

Impact of tumor size on outcome after stereotactic body radiation therapy for inoperable hepatocellular carcinoma

Abstract Stereotactic body radiation therapy (SBRT) for inoperable hepatocellular carcinoma (HCC) offers excellent local control rates. This study retrospectively analyzed the influence of different tumor size on treatment outcomes after SBRT. Between December 2008 and February 2014, 141 HCC patients were treated with Cyberknife SBRT. Patients were divided into 3 groups namely small tumors (⩽4 cm), intermediate-sized (>4–<10 cm), and large (≥10 cm) tumors. Treatment outcomes, prognoses, and safety at each tumor size were compared and analyzed. A total of 52 patients with small tumors, 55 with intermediate tumors, and 34 patients with large tumors were retrospectively analyzed with a median follow-up of 16 months. Objective responses were achieved at 96.15%, 90.90%, and 76.47% for small, intermediate, and large tumors, respectively (P ⩽ .0001) and the 3-year local control rates were 97.85%, 71.99%, and 82.14%, respectively (P = .0035). The 3-year overall survival rates were 50.26%, 45.29%, and 33.38% for small, intermediate, and large tumors, respectively (P = .3757). No significant differences were found in overall-survival, intra-hepatic recurrence free survival, disease-progression free survival, or distant metastasis-free survival. SBRT offers the best effective local control rate and response rate for small HCCs. However, tumor size did not significantly affect the overall survival rate, intra-hepatic recurrence free rate, or disease-progression free rate.

Comparison of Elixhauser and Charlson Methods for Predicting Oral Cancer Survival.

AbstractCancer survival correlates not only with the features of primary malignancy but also with the degree of underlying comorbidities. Of the multiple methods used for evaluating the impact of comorbidities on survival, the Charlson and Elixhauser methods are most common. This study compared these 2 comorbidity measures for predicting survival in oral cancer patients.Using the Taiwan National Health Insurance claims data (2008–2011), we acquired data regarding patients’ characteristics, comorbidities, and survival from 3583 oral cancer patients. Comorbidity was classified according to both the Charlson comorbidity and Elixhauser comorbidity based on the International Classification of Diseases, 9th Revision. The Elixhauser comorbidity score and Charlson comorbidity score were also calculated. The prediction of survival was determined using measures of discrimination, including the Akaike information criterion and Harrell C (C-statistic).The mean age of the study cohort was 52 ± 10 years, and 94.9% of the patients were male. The median follow-up time was 30.1 months, and the 3-year overall survival was 61.6%. Elixhauser comorbidity method added higher discrimination, compared with the Charlson comorbidity method (Harrell C, 0.677 vs 0.651). Furthermore, the Elixhauser comorbidity score outperformed the Charlson comorbidity score in continuous variable (Harrell C, 0.654 vs 0.646) and category (Harrell C, 0.658 vs 0.645).The Elixhauser method is a superior comorbidity risk-adjustment model for oral cancer survival prediction. Utilization of the Elixhauser comorbidity method may be encouraged for risk adjustment in oral cancer study.

Modified Tumor Classification With Inclusion of Tumor Characteristics Improves Discrimination and Prediction Accuracy in Oral and Hypopharyngeal Cancer Patients Who Underwent Surgery

AbstractSeveral histopathological characteristics have a significant prognostic impact on recurrence and survival rates in head and neck squamous cell carcinoma (HNSCC). We conducted a retrospective study on patients with HNSCC to compare traditional pathological T (pT) classification to a new T classification system that incorporates these histopathological characteristics.Newly diagnosed patients with HNSCC (n = 349) post major surgery were identified from the cancer registry database between 2004 and 2013. The pT and new T classification systems were compared with respect to recurrence-free survival (RFS), disease-specific survival (DSS), and survival rates using the Cox proportional hazards model with adjustments. The discriminatory ability of these 2 classification systems was evaluated using the adjusted hazard ratio (HR) and Akaike information criterion (AIC) in a multivariate regression model. The prediction accuracy was assessed using Harrells C-statistic.The new T classification, which incorporated tumor size, extent, and location with histopathological features had better discriminatory ability and monotonicity of gradients than did pT classification. The new T4 classification yielded a higher adjusted HR in RFS (HR, 4.11; 95% confidence interval [CI], 7.75–9.65) and in DSS (HR, 4.39; 95% CI, 1.6–12.03), and a lower AIC in recurrence (927 vs 969) and survival rates (791 vs 833).The new T classification system had better discriminatory ability in RFS and DSS compared with the routinely used American Joint Committee on Cancer (AJCC) pT classification system. Therefore, this new T classification system, which includes tumor size, location, extent, and histopathological features, could be used as an alternative to AJCC pT classification for patients with HNSCC.