Epidermal Growth Factor Receptor Mutation Status and Treatment Outcome for R0-Resected Patients with Stage 3 Non-small Cell Lung Cancer.

BACKGROUND: This study aimed to investigate the association of epidermal growth factor receptor (EGFR) mutation status with treatment outcome for patients with stage 3 non-small cell lung cancer (NSCLC) who had undergone a complete (R0) resection. METHODS: The study identified 3445 NSCLC patients tested for EGFR mutations between September 2001 and December 2011 at the Sun Yat-Sen University Cancer Center. Of these patients, 224 were stage 3 patients who had undergone R0 resections. RESULTS: These 224 R0-resected, pathologic stage 3A and 3B patients included 150 patients with wild-type EGFR and 74 patients with EGFR mutations. During a median follow-up period of 42 months (range, 4-133 months), pathologic stage was shown to be the only prognostic factor. The 3-year overall survival (OS) rates did not differ significantly from the OS rates for the wild-type and mutant EGFR groups (62.0 vs 67.2 %; p = 0.789). Multivariate analyses indicated that the patients in the mutant EGFR group with EGFR exon 19 mutations had a better OS rate (73.0 vs 61.1 %; p = 0.026). CONCLUSIONS: Cancer stage remained the significant prognostic factor in R0-resected stage 3 NSCLC patients. The presence of an EGFR mutation is more likely to be a predictive marker for the response to treatment with tyrosine kinase inhibitors. In the EGFR mutant group, the patients with an exon 19 mutation had better 3-year OS rates. These findings might be considered in future study designs.

MRI-detected residual retropharyngeal lymph node after intensity-modulated radiotherapy in nasopharyngeal carcinoma: Prognostic value and a nomogram for the pretherapy prediction of it.

BACKGROUND AND PURPOSE: To evaluate the prognostic value of MRI-detected residual retropharyngeal lymph node (RRLN) at three months after intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC) and second, to establish a nomogram for the pretherapy prediction of RRLN. MATERIALS AND METHODS: We included 1103 patients with NPC from two hospitals (Sun Yat-Sen University Cancer Center [SYSUCC, n = 901] and Dongguan People's Hospital [DGPH, n = 202]). We evaluated the prognostic value of RRLN using Cox regression model in SYSUCC cohort. We developed a nomogram for the pretherapy prediction of RRLN using logistic regression model in SYSUCC training cohort (n = 645). We assessed the performance of this nomogram in an internal validation cohort (SYSUCC validation cohort, n = 256) and an external independent cohort (DGPH validation cohort, n = 202). RESULTS: RRLN was an independent prognostic factor for OS (HR 2.08, 95% CI 1.32-3.29), DFS (HR 2.45, 95% CI 1.75-3.42), DMFS (HR 3.31, 95% CI 2.15-5.09), and LRRFS (HR 3.04, 95% CI 1.70-5.42). We developed a nomogram based on baseline Epstein-Barr virus DNA level and three RLN status-related features (including minimum axial diameter, extracapsular nodal spread, and laterality) that predicted an individual's risk of RRLN. Our nomogram showed good discrimination in the training cohort (C-index = 0.763). The favorable performance of this nomogram was confirmed in the internal and external validation cohorts. CONCLUSION: MRI-detected RRLN at three months after IMRT was an unfavorable prognostic factor for patients with NPC. We developed and validated an easy-to-use nomogram for the pretherapy prediction of RRLN.

[Influence of patient setup error on planning risk volumes for nasopharyngeal carcinoma patients receiving intensity-modulated radiation therapy].

BACKGROUND & OBJECTIVE: Determination of planning risk volumes (PRVs) for an organ at risk greatly affects dose optimization in designing the intensity-modulated radiation therapy (IMRT) regimen. Patient setup errors have been found to closely correlate to the definition of PRVs. This study was to investigate the safety margin for the organ at risk during IMRT planning for nasopharyngeal carcinoma (NPC) patients. METHODS: Nineteen NPC patients (stage T1-2N0M0) who received IMRT for the first time were studied. Repeated computed tomography (CT) scans were performed for the patients once a week during the whole treatment course. A total of 85 CT scan reports were obtained. Differences between patient positioning of each time and first treatment setup were caluculated by comparing the anatomical landmarks (that is, optical nerve, pituitary, spine, and parotid) on each CT scan image using Osiris software. RESULTS: The displacement of optical nerve and pituitary in X, Y, and Z directions were, in absolute values, (0.86+/-0.53) mm, (0.84+/-0.68) mm, and (0.93+/-1.02)mm, respectively. The standard deviations (SDs) of systematic errors for the axial vector displacement were 0.83 mm, 1.08 mm, and 1.21 mm, while the SDs of random errors were 0.85 mm, 0.83 mm and 1.14 mm. The displacement of spine and parotid in X, Y, and Z directions were, in absolute values, (0.98+/-0.74) mm, (1.25+/-0.88) mm, and (1.43+/-1.02) mm, respectively. The SDs of systematic errors for axial vector displacement were 0.98 mm, 1.35 mm, and 1.87 mm, while the SDs of random errors were 1.02 mm, 1.46 mm, and 1.54 mm. CONCLUSION: It is feasible to determine the size of a safety margin of IMRT for organs at risk using repeated CT scans for NPC patients.