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Stockton, CA, United States

Chitapanarux I.,Chiang Mai University | Tharavichitkul E.,Chiang Mai University | Jakrabhandu S.,Chiang Mai University | Klunklin P.,Chiang Mai University | And 5 more authors.
Journal of Radiation Research

Objective: To assess the treatment outcomes and to explore the determinants of clinical outcome in breast cancer patients with 1-3 positive nodes who did or did not receive postmastectomy radiotherapy (PMRT) in a tertiary care referral cancer center in Northern Thailand. Methods: We investigated a retrospective cohort of registered breast cancer patients at the Faculty of Medicine, Chiang Mai University, Thailand from 2001-2007. Analysis was performed using Cox regression models to identify factors affecting the overall survival (OS) and relapse-free survival (RFS) rates. Comparisons were made between two cohorts: women who received adjuvant PMRT (74 patients) and women who did not receive adjuvant PMRT (81 patients). Results: A total of 155 patients were included with a median follow-up period of 4.45 years. There was a statistically significant 4-year OS difference between the two groups of patients: 100% for the PMRT group and 93.1% for the non-PMRT group (P = 0.044). The 4-year RFS was 85.9% for patients receiving PMRT and 78.3% for patients who did not receive PMRT (P = 0.291). On multivariate analysis of OS, using hormonal treatment was the only significant independent factor associated with improved OS. On multivariate analysis of RFS, none of the variables were significantly associated with improved RFS. PMRT was notfound to be a prognostic variable related to the outcome of patients using a logistic regression model. Conclusion: Our retrospective, hospital-based analysis demonstrated that PMRT improved the treatment outcome in terms of OS for women with 1-3 node positive early-stage breast cancer. © 2013 The Author. Source

Chitapanarux I.,Chiang Mai University | Tharavichitkul E.,Chiang Mai University | Nobnop W.,Chiang Mai University | Wanwilairat S.,Chiang Mai University | And 2 more authors.
Journal of Radiation Research

The aim of this study was to compare the dosimetric parameters of whole-pelvis radiotherapy (WPRT) for cervical cancer between step-and-shoot IMRT (SaS-IMRT) and Helical Tomotherapy™ (HT). Retrospective analysis was performed on 20 cervical cancer patients who received WPRT in our center between January 2011 and January 2014. SaS-IMRT and HT treatment plans were generated for each patient. The dosimetric values for target coverage and organ-at-risk (OAR) sparing were compared according to the criteria of the International Commission on Radiation Units and Measurements 83 (ICRU 83) guidelines. Differences in beam-on time (BOT) were also compared. All the PTV dosimetric parameters (D5%, D50% and D95%) for the HT plan were (statistically significantly) of better quality than those for the SaS-IMRT plan (P-value < 0.001 in all respects). HT was also significantly more accurate than SaS-IMRT with respect to the D98% and Dmean of the CTV (P-values of 0.008 and <0.001, respectively). The median Conformity Index (CI) did not differ between the two plans (P-value = 0.057). However, the Uniformity Index for HT was significantly better than that for SaS-IMRT (P-value < 0.001). The median of D50% for the bladder, rectum and small bowel were significantly lower in HT planning than SaS-IMRT (P-value < 0.001). For D2%, we found that HT provided better sparing to the rectum and bladder (P-value < 0.001). However, the median of D2% for the small bowel was comparable for both plans. The median of Dmax of the head of the left femur was significantly lower in the HT plan, but this did not apply for the head of the right femur. BOT for HT was significantly shorter than for SaS-IMRT (P-value < 0.001). HT provided highly accurate plans, with more homogeneous PTV coverage and superior sparing of OARs than SaS-IMRT. In addition, HT enabled a shorter delivery time than SaS-IMRT. © 2015 The Author. Source

Chadha M.,Beth Israel Deaconess Medical Center | Vongtama D.,St Teresa Comprehensive Cancer Center | Friedmann P.,Yeshiva University | Parris C.,Beth Israel Deaconess Medical Center | And 3 more authors.
Clinical Breast Cancer

Background: We aimed to evaluate the incidence of acute toxicity in a 3-week accelerated radiation therapy (RT) schedule with a concomitant boost compared with the 6.5-week conventional schedule with a sequential boost for early-stage, node-negative breast cancer. Materials and Methods: This study included the first 50 patients treated on protocol using the accelerated schedule as well as 74 patients with comparable stages of disease treated over the same period using the conventional schedule. An accelerated schedule of 40.5 Gy × 2.7 Gy/fraction to the whole breast with 4.5 Gy × 0.3 Gy/fraction concomitant boost, for a delivered total dose of 45.0 Gy × 3.0 Gy/fraction in 15 fractions to the lumpectomy site. The conventional schedule used 46.8 Gy × 1.8 Gy to the whole breast with a sequential boost of 14.0 Gy × 2.0 Gy/fraction, delivering a total dose of 60.8 Gy × 33 fractions to the lumpectomy site. The side effects observed during RT and through the initial 8 weeks after treatment were scored for acute toxicity. Results: A lower incidence of < grade 2 skin toxicity was observed among patients treated on the accelerated schedule compared with those treated on the conventional schedule (p =.0015). There was a higher incidence of breast pain among patients receiving the conventional schedule (p =.045). No significant difference in the incidence of breast edema, fatigue, or hematologic side effects was observed between the 2 groups. Conclusion: Our observations suggest that there is acceptable toxicity with the accelerated schedule as used in this study. Further, it is not associated with a higher risk of acute toxicity when compared with the conventional schedule. Patients in the study are being followed, and clinical outcomes will be reported as the data mature. © 2012 Elsevier Inc. All rights reserved. Source

Chitapanarux I.,Chiang Mai University | Tharavichitkul E.,Chiang Mai University | Chakrabandhu S.,Chiang Mai University | Klunklin P.,Chiang Mai University | And 5 more authors.
Journal of the Medical Association of Thailand

Objective: This study reports the treatment outcome of radiotherapy alone for laryngeal cancer. Material and Method: A retrospective analysis was performed on 138 patients with stage I to IV squamous cell carcinoma of larynx who received radiotherapy alone in Division of Therapeutic Radiology and Oncology, Faculty of Medicine, Chiang Mai University, Thailand between 2003 and 2009. Results: The 4-year local control (LC) rate in all patients was 44.1%. The 4-year overall survival (OS) was 82.1%. The 4-year LC rates for stage I, II, III, and IV were 75.3%, 69.4%, 57.1%, and 36.9%,respectively (p = 0.0055). Finally, the 4-year OS rates for stage I, II, III, and IV were 85%, 78.6%, 91.1%, and 71.5%, respectively. The laryngeal preservation rate of all stages was 73%. Conclusion: In conclusion, the treatment outcome of radiotherapy alone in all stages of laryngeal cancer in our center was unsatisfactory when compared to other series. Source

Chitapanarux I.,Chiang Mai University | Kamnerdsupaphon P.,Chiang Mai University | Pukanhapan N.,Chiang Mai University | Tharavichitkul E.,St Teresa Comprehensive Cancer Center | Vongtama R.,St Teresa Comprehensive Cancer Center
Journal of Radiation Research

The aim of this study was to compare the efficacy and safety of concurrent chemoradiotherapy (CCRT) vs accelerated hyperfractionation with concomitant boost (CCB) as a primary treatment for patients with Stage 3-5 squamous cell carcinoma of head and neck (SCCHN). A total of 85 non-metastatic advanced SCCHN patients were accrued from January 2003 to December 2007. Of these, 48 and 37 patients received CCRT and CCB, respectively. The patients were randomized to receive either three cycles of carboplatin and 5-fluorouracil plus conventional radiotherapy (CCRT, 66 Gy in 6.5 weeks) or hybrid accelerated radiotherapy (CCB, 70 Gy in 6 weeks). The primary endpoint was determined by locoregional control rate. The secondary endpoints were overall survival and toxicity. With a median follow-up of 43 months (range, 3-102), the 5-year locoregional control rate was 69.6% in the CCRT arm vs 55.0% in the CCB arm (P = 0.184). The 5-year overall survival rate was marginally significantly different (P = 0.05): 76.1% in the CCRT arm vs 63.5% in the CCB arm. Radiotherapy treatment interruptions of more than three days were 60.4% and 40.5% in the CCRT arm and CCB arm, respectively. The median total treatment time was 55.5 days in the CCRT arm and 49 days in the CCB arm. The rate of Grade 3-4 acute mucositis was significantly higher in the CCB arm (67.6% vs 41.7%, P = 0.01), but no high grade hematologic toxicities were found in the CCB arm (27.2% vs 0%). CCRT has shown a trend of improving outcome over CCB irradiation in locoregionally advanced head and neck cancer. © The Author 2013. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Therapeutic Radiology and Oncology. Source

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