***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: BACKGROUND Concurrent chemoradiotherapy ( CCRT ) has been shown to improve outcomes for stage III-IV nasopharyngeal carcinoma ( NPC ) patients compared with radiotherapy ( RT ) alone , but the effectiveness of the combined therapy for stage II NPC patients is unknown . METHODS Patients with Chinese 1992 stage II NPC were r and omly assigned to receive either RT alone ( n = 114 ) or CCRT ( n = 116 ) . The CCRT patients were given concurrent cisplatin ( 30 mg/m(2 ) on day 1 ) weekly during RT . The primary endpoint was overall survival ( OS ) . Secondary endpoints were progression-free survival ( PFS ) , distant metastasis-free survival , and locoregional relapse-free survival . All patients were analyzed by the intent-to-treat principle . The Cox proportional hazards model was used to calculate hazard ratios ( HRs ) with 95 % confidence intervals ( CIs ) and in multivariable analyses to test the independent statistical significance of treatment intervention . Toxic effects and the response to treatment were analyzed using the χ(2 ) test . All statistical tests were two-sided . RESULTS With a median follow-up of 60 months , adding chemotherapy statistically significantly improved the 5-year OS rate ( 94.5 % vs 85.8 % ; HR of death = 0.30 , 95 % CI = 0.12 to 0.76 ; P = .007 ) , PFS ( 87.9 % vs 77.8 % ; HR of progression = 0.45 , 95 % CI = 0.23 to 0.88 ; P = .017 ) , and distant metastasis-free survival ( 94.8 % vs 83.9 % ; HR of distant relapse = 0.27 , 95 % CI = 0.10 to 0.74 ; P = .007 ) ; however , there was no statistically significant difference in the 5-year locoregional relapse-free survival rate ( 93.0 % vs 91.1 % ; HR of locoregional relapse = 0.61 , 95 % CI = 0.25 to 1.51 ; P = .29 ) . Multivariable analysis showed that the number of chemotherapy cycles was the only independent factor that was associated with OS , PFS , and distant control in stage II NPC . The CCRT arm experienced statistically significantly more acute toxic effects ( P = .001 ) , although the rate of late toxic effects did not increase statistically significantly . CONCLUSION Concurrent chemotherapy and radiotherapy is associated with a considerable survival benefit for patients with stage II NPC PURPOSE To compare directly the effect of intensity-modulated radiotherapy ( IMRT ) vs. conventional radiotherapy ( CRT ) on salivary flow and quality of life ( QoL ) in patients with early-stage nasopharyngeal carcinoma ( NPC ) . METHODS AND MATERIAL S Fifty-one patients with T2 , N0/N1 , M0 NPC took part in a r and omized controlled clinical study and received IMRT or CRT .  Stimulated whole ( SWS ) and parotid ( SPS ) saliva flow were measured and Medical Outcomes Short Form 36 ( SF-36 ) , European Organization for Research and Treatment of Cancer ( EORTC ) core quetionnaire , and EORTC head- and -neck module ( QLQ-H&N35 ) were completed at baseline and 2 , 6 , and 12 months after radiotherapy . RESULTS Forty-six patients ( 88 % ) were in disease remission 12 months after radiotherapy . At 12 months postradiotherapy , 12 ( 50.0 % ) and 20 patients ( 83.3 % ) in the IMRT group had recovered at least 25 % of preradiotherapy SWS and SPS flow respectively , compared with 1 ( 4.8 % ) and 2 patients ( 9.5 % ) , respectively , in the CRT group . Global health scores showed continuous improvement in QoL after both treatments ( p < 0.001 ) . However , after 12 months subscale scores for role-physical , bodily pain , and physical function were significantly higher in the IMRT group , indicating a better condition ( p < 0.05 ) . Dry mouth and sticky saliva were problems in both groups 2 months after treatment . In the IMRT group , there was consistent improvement over time with xerostomia-related symptoms significantly less common than in the CRT group at 12 months postradiotherapy . CONCLUSIONS IMRT was significantly better than CRT in terms of parotid sparing and improved QoL for early-stage disease . The findings support the case for assessment of health-related QoL in relation to head- and -neck cancer using a site-specific approach OBJECTIVE To compare the side effects of intensity modulated radiotherapy(IMRT ) and conventional radiotherapy in nasopharyngeal carcinoma . METHOD Sixty nine cases of nasopharyngeal carcinoma were r and om selected by stages , with 32 cases in IMRT group and 37 cases in conventional radiotherapy group . The target areas in IMRT group were nasopharyngeal carcinoma , parapharyngeal space and neck lymphatic area with the fractional dose of 2.00 - 2.12 Gy per time , for 33 - 35 times . The cases in conventional radiotherapy group were given facio-cervical field radiation , DT 40 - 60 Gy per time , for 20 - 30 times . The reinforcing dosage in lateral facial field increased to DT 70 Gy in the nasopharyngeal area . The prophylactic irradiation dose of the neck was DT 50 - 55 Gy . RESULT The incidence of dry mouth one year after radiotherapy in the IMRT and conventional radiotherapy groups were 9.38 % ( 3/32 ) and 94.59 % ( 35/37 ) respectively , with a significant difference between the two groups ( P < 0.01 ) . The incidence of difficulty in opening mouth in the IMRT and conventional radiotherapy groups were 6.25 % ( 2/32 ) and 72.97 % ( 27/37 ) respectively , with a significant difference between the two groups(P < 0.01 ) . CONCLUSION Compared with the conventional radiotherapy , IMRT may improve the control rate and obviously de creases the side effects . It could be recommended for the radiotherapy of nasopharyngeal carcinoma PURPOSE To investigate the feasibility of intensity-modulated radiation therapy ( IMRT ) with or without chemotherapy , and to assess toxicities , failure patterns , and survivals in patients with nasopharyngeal carcinoma ( NPC ) . PATIENTS AND METHODS Radiation consisted of 70 Gy given to the planning target volumes of primary tumor plus any N+ disease and 59.4 Gy given to sub clinical disease , delivered over 33 treatment days . Patients with stage T2b or greater or with N+ disease also received concurrent cisplatin ( 100 mg/m(2 ) ) on days 1 , 22 , and 43 followed by adjuvant cisplatin ( 80 mg/m(2 ) ) on day 1 ; fluorouracil ( 1,000 mg/m(2)/d ) on days 1 through 4 administered every 4 weeks for three cycles . Tumor , clinical status , and acute/late toxicities were assessed . The primary objective was to test the transportability of IMRT to a multi-institutional setting . RESULTS Between February 2003 and November 2005 , 68 patients with stages I through IVB NPC ( of which 93.8 % were WHO types 2 and 3 ) were enrolled . Prescribed IMRT ( target delineation ) was given to 83.8 % , whereas 64.9 % received chemotherapy per protocol . The estimated 2-year local progression-free ( PF ) , regional PF , locoregional PF , and distant metastasis-free rates were 92.6 % , 90.8 % , 89.3 % , and 84.7 % , respectively . The estimated 2-year PF and overall survivals were 72.7 % and 80.2 % , respectively . Acute grade 4 mucositis occurred in 4.4 % , and the worst late grade 3 toxicities were as follows : esophagus , 4.7 % ; mucous membranes , 3.1 % ; and xerostomia , 3.1 % . The rate of grade 2 xerostomia at 1 year from start of IMRT was 13.5 % . Only two patients complained of grade 3 xerostomia , and none had grade 4 xerostomia . CONCLUSION It was feasible to transport IMRT with or without chemotherapy in the treatment of NPC to a multi-institutional setting with 90 % LRPF rate reproducing excellent reports from single institutions . Minimal grade 3 and lack of grade 4 xerostomia were encouraging BACKGROUND AND PURPOSE To compare clinical outcomes and toxicities of two-dimensional conventional radiation therapy ( 2D-CRT ) and intensity modulated radiation therapy ( IMRT ) for the treatment of nasopharyngeal carcinoma ( NPC ) . MATERIAL S AND METHODS Between July 2003 and October 2008 , 616 patients with non-metastatic stage I to IVb NPC were prospect ively r and omized to receive 2D-CRT  ( n=310 ; mean age , 44.8±13.6 years ) or IMRT ( n=306 ; mean age , 46.7±12.5 years ) . Clinical outcomes and acute and late toxicities were determined and compared . RESULTS The 2 groups were comparable with respect to all parameters of demographics and disease characteristics ( all , p>0.05 ) . Median follow-up was 42 months ( range , 1 - 83 months ) . The 5-year actuarial local control rate was 90.5 % in the IMRT group and 84.7 % in the 2D-CRT group . The local control rates were 91 % for stage T3 and 81.5 % for stage T4 disease in the IMRT group and 80 % and 62.2 % in the 2D-CRT group , respectively . The 5-year actuarial nodal relapse-free survival ( NRFS ) rate was 92.4 % in the IMRT and 92.9 % in the 2D-CRT group ( p>0.05 ) . The NRFS was 93.9 % for N2 disease in the IMRT group and 91.4 % in the 2D-CRT group ( p=0.02 ) . The 5-year overall survival ( OS ) rate was 79.6 % for the IMRT group and 67.1 % for the 2D-CRT group ( p=0.001 ) . When stratified for stage , a significant difference was only noted for stage III disease . In terms of radiation-induced toxicities , patients in IMRT group had significantly lower radiation-induced toxicities than those in 2D-CRT group . CONCLUSION IMRT provides improved local-recurrence free survival , especially in late-stage NPC patients and is associated with a lower incidence of toxicities BACKGROUND AND PURPOSE In 2003 , the French Authority for Health ( HAS ) recommended the use of intensity modulated radiotherapy ( IMRT ) in prospect i ve trial before its routine use . The Oncology and Radiotherapy Group for Head and Neck Cancer ( GORTEC ) proposed to evaluate prospect ively acute and late toxicities , locoregional control and overall survival for patients treated for head and neck cancer ( HNC ) with IMRT and bilateral neck irradiation .  MATERIAL S AND METHODS Between 2002 and 2008 , 208 patients with HNC were treated with IMRT in 8 centres . There were 38 nasopharynx , 117 oropharynx , 25 pharyngo-larynx , 24 oral cavity and 4 unknown primary ( 28.5 % stage I-II and 71 % Stage III-IV ) . Ninety-three patients ( 46 % ) had postoperative IMRT and 78 patients ( 37.5 % ) received concurrent chemotherapy . The doses were 70 Gy to the gross tumour , 66 Gy to the high-risk postoperative sites and 50 Gy to the sub clinical disease . Toxicities were grade d according to the RTOG-EORTC scales . RESULTS The median follow-up was 25.3 months ( range : 0.4 - 72 months ) . There were 29 local-regional failures : 24 were in-field , three were marginal and one was out-field . The two-year loco-regional control and overall survival were 86 % and 86.7 % , respectively . At 18 months , grade ≥ 2 xerostomia was 16.1 % . A mean dose to the spared parotid below 28 Gy led to significantly less grade ≥ 2 xerostomia ( 8.5 % vs 24 % ) with a relative risk of 1.2 [ 95 % CI : 1.02 - 1.41 , p = 0.03 ] . Grade ≥ 2 xerostomia increased by approximately 3 % per Gy of mean parotid dose up to 28 , Gy then 7 % per Gy above 33 Gy . CONCLUSIONS IMRT for HN cancer seems to reduce late toxicities without jeopardising local control and overall survival PURPOSE This r and omized trial compared the rates of delayed xerostomia between two-dimensional radiation therapy ( 2 
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CONCLUSIONS The meta- analysis demonstrates that IMRT provides improved long-term tumor overall survival and local control including LRFS and PFS .
Additionally , IMRT yields a lower incidence of late toxicities induced by irradiation in NPC patients .
Compared to 2D-RT , IMRT may be an effective treatment for patients with NPC .