Cheng Guang Lin

Local control, survival, and late toxicities of locally advanced nasopharyngeal carcinoma treated by simultaneous modulated accelerated radiotherapy combined with cisplatin concurrent chemotherapy

The aim of this phase 2 study was to determine the long‐term local control, survival, and late toxicities among patients with locally advanced nasopharyngeal carcinoma (NPC) treated with intensity‐modulated radiotherapy (IMRT) with the simultaneous modulated accelerated radiation therapy (SMART) boost technique and concurrent chemotherapy.

Initial experience using intensity-modulated radiotherapy for recurrent nasopharyngeal carcinoma

PURPOSE To report our initial experience on the feasibility, toxicity, and tumor control using intensity-modulated radiotherapy (IMRT) for retreatment of recurrent nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS A total of 49 patients with locoregional recurrent carcinoma in the nasopharynx were treated with IMRT between January 2001 and February 2002 at the Sun Yat-Sen University Cancer Center, Guangzhou, China. The average time to the nasopharyngeal recurrence was 30.2 months after initial conventional RT. The median isocenter dose to the nasopharynx was 70 Gy (range 60.9-78.0) for the initial conventional RT. All patients were restaged at the time of recurrence according to the 1992 Fuzhou, China staging system on NPC. The number of patients with Stage I, II, III and IV disease was 4, 9, 10, and 26, respectively. T1, T2, T3, and T4 disease was found in 4, 9, 11, and 25 patients, respectively. N0, N1, N2, and N3 disease was found in 46, 2, 0, and 1 patient, respectively. Invasion of the nasal cavity, maxillary sinus, ethmoid sinus, sphenoid sinus, and cavernous sinus and erosion of the base of the skull was found in 8, 1, 3, 8, 15, and 20 patients, respectively. The gross tumor volume (GTV) was contoured according to the International Commission on Radiation Units and Measurements (ICRU) Report 62 guidelines. The critical structures were contoured, and the doses to critical structures were constrained according to ICRU 50 guidelines. The GTV in the nasopharynx and positive lymph nodes in the neck received a prescription dose of 68-70 Gy and 60 Gy, respectively. All patients received full-course IMRT. Three patients who had positive lymph nodes were treated with five to six courses of chemotherapy (cisplatin + 5-fluorouracil) after IMRT. RESULTS The treatment plans showed that the percentage of GTV receiving 95% of the prescribed dose (V(95-GTV)) was 98.5%, and the dose encompassing 95% of GTV (D(95-GTV)) was 68.1 Gy in the nasopharynx. The mean dose to the GTV was 71.4 Gy. The average doses of the surrounding critical structures were much lower than the tolerable thresholds. At a median follow-up of 9 months (range 3-13), the locoregional control rate was 100%. Three cases (6.1%) of locoregional residual disease were seen at the completion of IMRT, but had achieved a complete response at follow-up. Three patients developed metastases at a distant site: two in the bone and one in the liver and lung at 13 months follow-up. Acute toxicity (skin, mucosa, and xerostomia) was acceptable according to the Radiation Therapy Oncology Group criteria. Tumor necrosis was seen toward the end of IMRT in 14 patients (28.6%). CONCLUSION The improvement in tumor target coverage and significant sparing of adjacent critical structures allow the feasibility of IMRT as a retreatment option for recurrent NPC after initial conventional RT. This is the first large series using IMRT to reirradiate local recurrent NPC after initial RT failed. The treatment-related toxicity profile was acceptable. The initial tumor response/local control was also very encouraging. In contrast to primary NPC, recurrent NPC reirradiated with high-dose IMRT led to the shedding of tumor necrotic tissue toward the end of RT. More patients and longer term follow-up are warranted to evaluate late toxicity and treatment outcome.

Results of a phase 2 study examining the effects of omitting elective neck irradiation to nodal levels IV and Vb in patients with N 0-1 nasopharyngeal carcinoma

PURPOSE To evaluate the patterns of nodal failure and toxicity in clinically negative necks of N0-1 nasopharyngeal carcinoma (NPC) patients who were treated with intensity modulated radiation therapy (IMRT) but did not receive elective neck irradiation (ENI) to level IV and Vb nodes. METHODS AND MATERIALS We conducted a phase 2 prospective study in N0-1 NPC patients treated with IMRT. ENI included the retropharyngeal nodes and levels II to Va but omitted levels IV and Vb in clinically negative necks. Patterns of nodal failure, regional control (RC), and late toxicity were evaluated. RESULTS Between 2001 and 2008, a total of 212 patients (128 N0 and 84 N1) were enrolled in the study. Seven patients (4 in-field and 3 out-of-field) developed nodal failure. One patient (0.5%) developed nodal failure at level Vb, but no patients developed nodal failure at level IV. The 5-year RC rates of the entire group, N0 patients and N1 patients were 95.6%, 98.2%, and 91.3%, respectively. Fifteen patients (7.1%) developed distant metastases. The 5-year distant failure-free survival (DFFS) and overall survival (OS) rates were 91.4% and 89.8%, respectively. The rates of grade 2 or greater skin dystrophy, subcutaneous fibrosis and xerostomia were 6.2%, 16.6%, and 17.9%, respectively. CONCLUSIONS The rate of out-of-field nodal failure when omitting ENI to levels IV and Vb in clinically negative necks of patients with N0-1 NPC was extremely low; therefore, a further phase 3 study is warranted.

Effect of total dose and fraction size on survival of patients with locally recurrent nasopharyngeal carcinoma treated with intensity-modulated radiotherapy: a phase 2, single-center, randomized controlled trial.

The optimal model of total dose and fraction size for patients with locally recurrent nasopharyngeal carcinoma treated with intensity‐modulated radiotherapy (IMRT) remains unclear. The authors designed a randomized phase 2 clinical trial to investigate the efficacy of 2 different models, with the objective of determining an optimal model.

Effect of total dose and fraction size on survival of patients with locally recurrent nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

The optimal model of total dose and fraction size for patients with locally recurrent nasopharyngeal carcinoma treated with intensity‐modulated radiotherapy (IMRT) remains unclear. The authors designed a randomized phase 2 clinical trial to investigate the efficacy of 2 different models, with the objective of determining an optimal model.

The development and implementation of MOSAIQ Integration Platform (MIP) based on the radiotherapy workflow

To meet the special demands in China and the particular needs for the radiotherapy department, a MOSAIQ Integration Platform CHN (MIP) based on the workflow of radiation therapy (RT) has been developed, as a supplement system to the Elekta MOSAIQ. The MIP adopts C/S (client-server) structure mode, and its database is based on the Treatment Planning System (TPS) and MOSAIQ SQL Server 2008, running on the hospital local network. Five network servers, as a core hardware, supply data storage and network service based on the cloud services. The core software, using C# programming language, is developed based on Microsoft Visual Studio Platform. The MIP server could offer network service, including entry, query, statistics and print information for about 200 workstations at the same time. The MIP was implemented in the past one and a half years, and some practical patient-oriented functions were developed. And now the MIP is almost covering the whole workflow of radiation therapy. There are 15 function modules, such as: Notice, Appointment, Billing, Document Management (application/execution), System Management, and so on. By June of 2016, recorded data in the MIP are as following: 13546 patients, 13533 plan application, 15475 RT records, 14656 RT summaries, 567048 billing records and 506612 workload records, etc. The MIP based on the RT workflow has been successfully developed and clinically implemented with real-time performance, data security, stable operation. And it is demonstrated to be user-friendly and is proven to significantly improve the efficiency of the department. It is a key to facilitate the information sharing and department management. More functions can be added or modified for further enhancement its potentials in research and clinical practice.