Prognostic value of MRI-derived masticator space involvement in IMRT-treated nasopharyngeal carcinoma patients

OBJECTIVES: This retrospective study reassessed nasopharyngeal carcinoma (NPC) patients treated with intensity-modulated radiation therapy (IMRT), to determine the significance how magnetic resonance imaging (MRI)-derived masticator space involvement (MSI) affected patients’ prognosis. METHODS: One thousand one hundred ninety seven NPC patients who had complete set of MRI and medical records were enrolled. Basing on their MRI findings, the T-categories of tumors were identified according to the seventh edition of American Joint Committee on Cancer staging system, which considers MSI a prognostic indicator for NPCs. Rates of overall survival (OS), local relapse-free survival (LRFS), regional relapse-free survival (RRFS) and distant metastasis-free survival (DMFS) were analyzed by the Kaplan-Meier method, and the Log-Rank test compared their differences. Cox regression analysis was employed to evaluate various prognostic factors systematically. Statistical analyses were conducted with SPSS 18.0 software, P value < 0.05 was considered statistically significant. RESULTS: Medial pterygoid muscle (MPM) was involved in 283 (23.64 %) cases, of which lateral pterygoid muscle (LPM) was concurrently affected in 181 (15.12 %) and infratemporal fossa (ITF) in 19 (1.59 %). Generally, MSI correlated with an OS, LRFS, and DMFS consistent with a T4-stage diagnosis (P > 0.05). Although different degrees of MSI presented a similar OS and DMFS (P > 0.1), tumors involving LPM had a relatively poorer LRFS than those affected the MPM only (P = 0.027), even for subgroup of patients composed of T3 and T4 classifications (P = 0.035). A tumor involving MPM brought an LRFS consistent with a T2 or T3-stage disease (P > 0.1). If the tumor affected LPM or ITF concurrently, the survival outcomes were more consistent with a T4-stage disease (P > 0.1). Nevertheless, compared to tumor infiltrating MPM, those invading LPM or ITF more frequently spread into other concurrent sites that earned higher T-staging categories. Moreover, multivariate analyses indicated the degree of MSI was a significant prognostic factor for the OS of NPCs (P = 0.036). CONCLUSIONS: Degree of MSI is a significant prognosticator for the OS of IMRT-treated NPCs, and the prognosis of patients with lateral MSI extension (LPM and ITF) were shown to be significantly worse than those affected only MPM or the T3-stage disease. Thus, it is highly recommended that lateral MSI extension be a higher T-staging category

Benefit of percutaneous endoscopic gastrostomy in patients undergoing definitive chemoradiotherapy for locally advanced nasopharyngeal carcinoma

BACKGROUND AND AIM: To evaluate the impact of percutaneous endoscopic gastrostomy (PEG) tube on nutritional status, treatment-related toxicity, and treatment tolerance in patients with locally advanced nasopharyngeal carcinoma (NPC) who underwent chemoradiotherapy. PATIENTS AND METHODS: We enrolled 133 consecutive non-metastatic NPC (III/IV stage) patients, who were treated with prophylactic PEG feeding before the initiation of concurrent chemoradiotherapy (CCRT) between June 1, 2010 and June 30, 2014. Meanwhile, another 133 non-PEG patients, who were matched for age, gender, and tumor, node, metastases stage, were selected as historical control cohort. Weight and nutritional status changes from pre-radiotherapy to the end of radiotherapy were evaluated, and treatment tolerance and related acute toxicities were analyzed as well. RESULTS: We found that significantly more patients (91.73%) in the PEG group could finish two cycles of CCRT, when compared with those in the non-PEG group (57.89%) (P<0.001). We also indicated that more patients (50.38%) in the non-PEG group experienced weight loss of ≥5%, while the phenomenon was only found in 36.09% patients in the PEG group (P=0.019). In addition, the percentage of patients who lost ≥10% of their weight was similar in these two groups. Changes in albumin and prealbumin levels during radiotherapy in the non-PEG group were higher than those obtained for the PEG group with significant differences (P-values of 0.023 and <0.001, respectively). Furthermore, patients in the PEG group had significantly lower incidence of grade III acute mucositis than those in the non-PEG group (22.56% vs 36.84%, P=0.011). Tube-related complications occurred only in 14 (10.53%) patients in the PEG group, including incision infection of various degrees. CONCLUSION: PEG and intensive nutrition support may help to minimize body weight loss, maintain nutritional status, and offer better treatment tolerance for patients with locally advanced NPC who underwent CCRT

Sequential chemotherapy and intensity-modulated radiation therapy in the management of locoregionally advanced nasopharyngeal carcinoma: Experience of 370 consecutive cases

<p>Abstract</p> <p>Introduction</p> <p>To investigate the outcome of locoregionally advanced nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiation therapy (IMRT) after induction chemotherapy, with or without concomitant chemotherapy.</p> <p>Methods</p> <p>Between August 2003 and March 2007, 370 patients with locoregionally advanced NPC were treated with IMRT. Presenting stages were stage IIB in 62, stage III in 197, and stage IVA/B in 111 patients. All patients except for 36 patients with cervical lymphadenopathy of 4 cm or less in diameter received 2 cycles of cisplatin-based neoadjuvant chemotherapy. Forty-eight patients received cisplatin-based concurrent chemotherapy as well.</p> <p>Results</p> <p>With a median follow-up time of 31 months (range 5 to 61 months), the 3-year local control, regional control, metastasis-free survival (MFS), disease-free survival (DFS) and overall survival (OS) rates were 95%, 97%, 86%, 81% and 89%, respectively. Multivariate analyses revealed that both age (≤ 60 vs. >60) and N-classification are significant prognosticators for OS (P = 0.001, hazard ratio [HR] 2.395, 95% confidence interval [CI] 1.432-4.003; P = 0.012, hazard ratio [HR] 2.614, 95% confidence interval [CI] 1.235-5.533); And N-classification is the only significant predicative factor for MFS (P = 0.002, [HR] 1.99, 95% CI 1.279-3.098). T-classification and concurrent chemotherapy were not significant prognostic factors for local/regional control, MFS, DFS, or OS. Subgroup analysis revealed that concurrent chemotherapy provided no significant benefit to IMRT in locoregionally advanced NPC, but was responsible for higher rates of grade 3 or 4 acute toxicities (50% vs. 29.8%, P < 0.005). No grade 3 or 4 late toxicity including xerostomia was observed. However, two patients treated with IMRT and neoadjuvant but without concurrent and adjuvant chemotherapy died of treatment related complications.</p> <p>Conclusion</p> <p>IMRT following neoadjuvant chemotherapy produced a superb outcome in terms of local control, regional control, MFS, DFS, and OS rates in patients with stage IIB to IVB NPC. Effective treatment strategy is urgently needed for distant control in patients diagnosed with locoregionally advanced NPC.</p

Systèmes d’imagerie intégrés ou associés aux appareils de radiothérapie

Cet ouvrage, écrit par des physiciens médicaux et des médecins spécialistes expérimentés, a été coordonné par le Dr es Sciences Ginette MARINELLO, ex-Chef de l'Unité de Radiophysique et de Radioprotection du Patient du CHU Henri Mondor de Créteil (France) et le Pr Jianji PAN, Chef du Service de Radiothérapie de l'Institut du Cancer et Directeur du Centre d'Assurance de Qualité de la Province du Fujian (RP de Chine). Il a pour but de faire le point sur les différents systèmes d'imagerie associés aux accélérateurs modernes de radiothérapie : EPID, systèmes d'imagerie embarqués à 2 ou 3 dimensions utilisant des RX de basse ou haute énergie, systèmes d'imagerie fixés au sol et au plafond... et systèmes d'imagerie indépendants irradiants ou non irradiants (systèmes optiques d'imagerie surfacique et à ultra-sons). Outre une description des systèmes, le principe de formation et d'exploitation des images produites est expliqué et illustré par de nombreux exemples pratiques. Les contrôles de qualité à effectuer obligatoirement à leur réception, puis périodiquement, pour assurer une qualité d'image indispensable, sont détaillés ainsi que les matériels et méthodes à utiliser et les tolérances acceptables. Une partie importante de l'ouvrage est consacrée à la pratique clinique avec de nombreux exemples montrant les possibilités et l'intérêt de l'utilisation des appareils d'imagerie pour les irradiations standard (sein), la modulation d'intensité IMRT ou VMAT (ORL), les irradiations stéréotaxiques intracrâniennes ou extracrâniennes (métastases osseuses) ou pendant les différentes stratégies d'irradiation des tumeurs mobiles (poumon et foie), et la protonthérapie (tumeurs de la base du crâne et mélanomes oculaires). L'utilisation de l'EPID comme dosimètre de transit pour le contrôle in vivo et l'enregistrement des doses délivrées aux patients pendant l'irradiation fait l'objet de tout un chapitre contenant, entre autres, la description des méthodes de calcul sur lesquelles sont basés différents logiciels. Enfin, un dernier chapitre est dédié aux méthodes d'évaluation des doses délivrées spécifiquement par les différents types d'imagerie et aux problèmes qu'elles posent. De par son contenu, étayé par une importante liste de références bibliographiques et de nombreuses figures, cet ouvrage s'avère être un outil indispensable pour tous ceux qui pratiquent la radiothérapie et s'intéressent à la radioprotection des patients, qu'ils soient médecins, physiciens médicaux, dosimétristes, manipulateurs d'électroradiologie médicale ou personnel technique et paramédical..., et bien sûr pour les étudiants

Changes in Tumor Volumes and Spatial Locations Relative to Normal Tissues During Cervical Cancer Radiotherapy Assessed by Cone Beam Computed Tomography

Purpose: To assess changes in the volumes and spatial locations of tumors and surrounding organs by cone beam computed tomography during treatment for cervical cancer. Materials and Methods: Sixteen patients with cervical cancer had intensity-modulated radiotherapy and off-line cone beam computed tomography during chemotherapy and/or radiation therapy. The gross tumor volume (GTV-T) and clinical target volumes (CTVs) were contoured on the planning computed tomography and weekly cone beam computed tomography image, and changes in volumes and spatial locations were evaluated using the volume difference method and Dice similarity coefficients. Results: The GTV-T was 79.62 cm3 at prior treatment (0f) and then 20.86 cm3 at the end of external-beam chemoradiation. The clinical target volume changed slightly from 672.59 cm3 to 608.26 cm3, and the uterine volume (CTV-T) changed slightly from 83.72 cm3 to 80.23 cm3. There were significant differences in GTV-T and CTV-T among the different groups ( P &lt; .001), but the clinical target volume was not significantly different in volume ( P &gt; .05). The mean percent volume changes ranged from 23.05% to 70.85% for GTV-T, 4.71% to 6.78% for CTV-T, and 5.84% to 9.59% for clinical target volume, and the groups were significantly different ( P &lt; .05). The Dice similarity coefficient of GTV-T decreased during the course of radiation therapy ( P &lt; .001). In addition, there were significant differences in GTV-T among different groups ( P &lt; .001), and changes in GTV-T correlated with the radiotherapy ( P &lt; .001). There was a negative correlation between volume change rate (DV) and Dice similarity coefficient in the GTV-T and organs at risk ( r &lt; 0; P &lt; .05). Conclusion: The volume, volume change rate, and Dice similarity coefficient of GTV-T were all correlated with increase in radiation treatment. Significant variations in tumor regression and spatial location occurred during radiotherapy for cervical cancer. Adaptive radiotherapy approaches are needed to improve the treatment accuracy for cervical cancer. </jats:sec