***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: PURPOSE To investigate the impact of xerostomia on overall quality of life ( QoL ) outcome and related dimensions among head and neck cancer patients treated with primary radiotherapy .  METHODS AND MATERIAL S A total of 288 patients with Stage I-IV disease without distant metastases were included .  Late xerostomia according to the Radiation Therapy Oncology Group ( RTOG-xerostomia ) and QoL ( European Organization for Research and Treatment of Cancer QLC-C30 ) were assessed at baseline and every 6th month from 6 months to 24 months after radiotherapy . RESULTS A significant association was found between RTOG-xerostomia and overall QoL outcome ( effect size [ ES ] 0.07 , p < 0.001 ) . A significant relationship with global QoL , all functioning scales , and fatigue and insomnia was observed . A significant interaction term was present between RTOG-xerostomia and gender and between RTOG-xerostomia and age . In terms of gender , RTOG-xerostomia had a larger impact on overall QoL outcome in women ( ES 0.13 for women vs. 0.07 for men ) . Furthermore , in women ES on individual scales were larger , and a marked worsening was observed with increasing RTOG-xerostomia . No different ES according to age was seen ( ES 0.10 for 18 - 65 years vs. 0.08 for > 65 years ) . An analysis of the impact of RTOG-xerostomia on overall QoL outcome over time showed an increase from 0.09 at 6 months to 0.22 at 24 months . With elapsing time , a worsening was found for these individual scales with increasing RTOG-xerostomia . CONCLUSIONS The results of this prospect i ve study are the first to show a significant impact of radiation-induced xerostomia on QoL. Although the incidence of Grade > or = 2 RTOG-xerostomia decreases with time , its impact on QoL increases . This finding emphasizes the importance of prevention of xerostomia AIMS To evaluate the long-term late adverse effects and treatment outcome in patients treated for advanced squamous cell carcinomas of the head and neck with continuous , hyperfractionated , accelerated radiation therapy ( CHART ) .  MATERIAL S AND METHODS One hundred and twenty-six consecutive patients were entered into a non-r and omised study of CHART alone with salvage treatment reserved for locoregional recurrence . The primary end points were locoregional control and late treatment-related morbidity . Time-incidence curves and statistical comparisons were obtained by computing actuarial event-free intervals using the product-limit ( Kaplan-Meier ) method . The prevalence rate of adverse effects was calculated using yearly intervals . Patients have been followed over a 15-year period . RESULTS The actuarial 12-year locoregional recurrence-free rate after radiotherapy alone was 46 % , which was increased by 15 % with the use of salvage treatment ( hazard ratio for recurrence with CHART alone 1.23 , confidence interval 1.017 - 1.494 ; P=0.033 ) . Actuarial estimates of severe adverse effects at this time were : dysphagia 12 % ( grade 4 ) ; subcutaneous fibrosis 3 % ; xerostomia 15 % . Ulcers of mucous membranes were observed in 18 % of patients . As expected , the prevalence of events was lower than that calculated by the life-table method . CONCLUSIONS Few , if any , studies have documented and reported on long-term adverse effects and treatment outcomes as in this pilot trial of CHART ( median follow-up time of those alive at 5 years or more is 11 years and the maximum follow-up time is 18 years ) . The low level of moderate to severe long-term morbidity together with a good and maintained level of locoregional tumour control indicates that CHART achieves a therapeutic benefit in patients with advanced squamous cell carcinoma of the head and neck Background : Data on early treatment-related morbidity after  radiotherapy alone ( RT ; 217 patients ) or combined with chemotherapy ( RT + CT ; 182 patients ) of head and neck squamous cell carcinoma are analyzed . Patients and Methods : The patients were treated between November 1985 and November 1996 in four Swiss centers that independently introduced combined-modality therapy in selected cases of head and neck cancer .  RT schedules varied among the four centers , but within each institution all patients received the same dose-fractionation schedule irrespective of whether they had CT or not . The following early morbidity items were evaluated : skin , mucosa , larynx , salivary gl and s , dysphagia , weight loss , and toxic death . Toxicity was scored using the EORTC/RTOG scale . Results : Although considerable variation was noted among the treatment schedules/centers , the main findings are as follows : ( 1 ) early morbidity was significantly enhanced after all five RT + CT schedules compared with RT alone ; ( 2 ) typically , a third of the patients lost > 10 % of their body weight during concurrent RT + CT as compared with 10 % of the patients receiving RT alone ; ( 3 ) at 12 weeks , the prevalence of grade 2 morbidity was 25–60 % after RT + CT as compared with 4–20 % after RT alone . Conclusion : A number of early morbidity items were found to be more prevalent and /or more severe after RT + CT than after RT alone . Hintergrund : Vorstellung der akuten Nebenwirkungen nach alleiniger Radiotherapie ( RT ; 217 Patienten ) oder kombinierter Radiochemotherapie ( RT + CT ; 182 Patienten ) bei Patienten mit Hals-Nasen-Ohren-Tumoren . Patienten und Method ik : Die Patienten wurden zwischen November 1985 und November 1996 in vier schweizerischen Spitälern beh and elt . Dabei kamen verschiedene unabhängige , kombinierte Beh and lungen für fortgeschrittene Hals-Nasen-Ohren-Karzinome zur Anwendung . CT- und RT-Protokolle waren unterschiedlich , innerhalb jedes einzelnen Zentrums wurden jedoch alle Patienten nach dem gleichen Bestrahlungsschema beh and elt ( mit oder ohne CT ) . Folgende akute Nebenwirkungen wurden erfasst : Haut , Schleimhaut , Larynx , Speichelfluss , Dysphagie , Gewichtsverlust und Tod durch Komplikationen . Die Beschreibung der akuten Toxizität erfolgte nach der EORTC/RTOG-Skala . Ergebnisse : Trotz erheblicher Unterschiede in der Bestrahlungstechnik zwischen den Spitälern sind die wichtigsten Ergebnisse folgende : 1 . Die akuten Nebenwirkungen waren bei kombinierter RT + CT signifikant stärker als bei alleiniger RT ; 2 . ein Drittel der Patienten verlor > 10 % ihres Körpergewichts während der kombinierten RT + CTC ; 3 . 12 Wochen nach Abschluss der Beh and lung st and eine Grad-2-Toxizität in 25–60 % nach kombinierter RT + CT und in 4–20 % nach alleiniger RT i m Vordergrund . Schlussfolgerung : Die akuten Nebenwirkungen waren nach kombinierter RT + CT stärker und häufiger als nach alleiniger Bestrahlung PURPOSE Irradiation of the parotid gl and s causes salivary dysfunction , result ing in reduced salivary flow . Recovery can be seen with time ; however , long-term prospect i ve data are lacking . The objective of this study was to analyze the long-term parotid gl and function after irradiation for head- and -neck cancer . METHODS AND MATERIAL S A total of 52 patients with head- and -neck cancer and treated with radiotherapy ( RT )  were prospect ively evaluated . Stimulated bilateral parotid salivary flow rates were measured before RT and 6 weeks , 6 months , 12 months , and at least 3.5 years after RT completion . A complication was defined as a stimulated parotid flow rate of < 25 % of the pre-RT flow rate . The normal tissue complication probability model proposed by Lyman was fit to the data . Multilevel techniques were used to model the patterns of flow rates with time . RESULTS The mean stimulated flow rate of the parotid gl and s before RT was 0.31 mL/min ( st and ard deviation [ SD ] , 0.21 ) . This was reduced to 0.14 mL/min ( SD , 0.15 ) at 6 weeks after RT and recovered to 0.20 mL/min ( SD , 0.22 ) at 6 months and 0.19 mL/min ( SD , 0.21 ) at 12 months after RT . The mean stimulated flow rate was 0.25 mL/min ( SD , 0.28 ) 5 years after RT . The mean dose to the parotid gl and result ing in a 50 % complication probability increased from 34 Gy at 6 weeks to 40 Gy at 6 months , 42 Gy at 12 months , and 46 Gy at 5 years after RT . Multilevel modeling indicated that both dose and time were significantly associated with the flow ratio . CONCLUSION Salivary output can still recover many years after RT . At 5 years after RT , we found an increase in the salivary flow rate of approximately 32 % compared with at 12 months after RT 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 PURPOSE We report the 5-year survival and late toxicity results of a r and omized clinical trial , which showed a 3-year improvement in overall survival and locoregional control of stage III or IV oropharynx carcinoma , using concomitant radiochemotherapy ( arm B ) , compared with st and ard radiotherapy ( arm A ) . PATIENTS AND METHODS A total of 226 patients were entered onto a phase III multicenter r and omized trial comparing radiotherapy alone ( 70 Gy in 35 fractions ; arm A ) with concomitant radiochemotherapy ( 70 Gy in 35 fractions with three cycles of a 4-day regimen comprising carboplatin and fluorouracil ; arm B ) . Prognostic factors were evaluated by univariate and multivariate analysis . Five-year late toxicity was evaluated using National Cancer Institute Common Toxicity Criteria for neurological toxicity , hearing , taste , m and ibula , and teeth damage , and Radiation Therapy Oncology Group toxicity criteria for skin , salivary gl and , and mucosa . RESULTS Five-year overall survival , specific disease-free survival , and locoregional control rates were 22 % and 16 % ( log-rank P = .05 ) , 27 % and 15 % ( P = .01 ) , and 48 % and 25 % ( P = .002 ) , in arm B and arm A , respectively . Stage IV , hemoglobin level lower than 125 g/L , and st and ard treatment were independent prognostic factors of short survival and locoregional failure by univariate and multivariate analysis . One or more grade 3 to 4 complications occurred in 56 % of the patients in arm B , compared with 30 % in arm A ( P was not significant ) . CONCLUSION Concomitant radiochemotherapy improved overall survival and locoregional control rates and does not statistically increase severe late morbidity . Anemia was the most important prognostic factor for survival in both arms AIMS To review the Batra Hospital and Medical Research Centre experience of using compensator-based intensity-modulated radiotherapy ( IMRT ) to treat head and neck cancer . MATERIAL 
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Conclusions Salivary gl and hypofunction and xerostomia are induced by radiotherapy in the head and neck region depending on the cumulative radiation dose to the gl and tissue .
Other cancer treatments also induce salivary gl and hypofunction , although to a lesser severity , and in the case of chemotherapy and immunotherapy , the adverse effect is temporary .