human
***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: The role of post-operative radiotherapy for patients with non-small-cell lung cancer ( NSCLC ) is unclear despite five previous r and omised trials . One deficiency with these trials was that they did not include adequate TNM staging , and so the present r and omised trial was design ed to compare surgery alone ( S ) with surgery plus post-operative radiotherapy ( SR ) in patients with pathologically staged T1 - 2 , N1 - 2 . M0 NSCLC . Between July 1986 and October 1993 , 308 patients ( 154 S , 154 SR ) were entered from 16 centres in the UK . The median age of the patients was 62 years , 74 % were male , > 85 % had normal or near normal levels of general condition , activity and breathlessness , 68 % had squamous carcinoma , 52 % had had a pneumonectomy , 63 % had N1 disease and 37 % N2 disease . SR patients received 40 Gy in 15 fractions starting 4 - 6 weeks post-operatively . Overall there was no advantage to either group in terms of survival , although definite local recurrence and bony metastases appeared less frequently and later in the SR group . In a subgroup analysis , in the N1 group no differences between the treatment groups were seen , but in the N2 group SR patients appeared to gain a one month survival advantage , delayed time to local recurrence and time to appearance of the bone metastases . There is , therefore , no clear indication for post-operative radiotherapy in N1 disease , but the question remains unresolved in N2 disease BACKGROUND AND PURPOSE To evaluate the benefits and the drawbacks of post-operative radiotherapy in completely resected Stage I ( a and b ) non-small cell lung cancer ( NSCLC ) . MATERIAL S AND METHODS Patients with pathological Stages Ia and Ib NSCLC have been r and omized into two groups : Group 1 ( G1 ) received adjuvant radiotherapy , Group 0 ( G0 ) the control group did not receive any adjuvant therapy .  Local control , toxicity and survival have been evaluated . RESULTS Between July 1989 and June 1997 , 104 patients with pathological stage I NSCLC have been enrolled in this study . Fifty-one patients were r and omized to G1 and 53 to G0 . Six patients have been excluded from the study due to incomplete follow-up data . Regarding local control , one patient in the G1 group had a local recurrence ( 2.2 % ) while in the G0 12 local recurrences have been observed ( 23 % ) . Seventy-one percent of patients are disease-free at 5 years in G1 and 60 % in G0 ( P=0.039 ) . Overall 5-year survival ( Kaplan-Meier ) showed a positive trend in the treated group : 67 versus 58 % ( P=0.048 ) . Regarding toxicity in G1 , six patients experienced a grade 1 acute toxicity . Radiological evidence of long-term lung toxicity , with no significant impairment of the respiratory function , has been detected in 18 of the 19 patients who have been diagnosed as having a post-radiation lung fibrosis . CONCLUSIONS Adjuvant radiotherapy gave good results in terms of local control in patients with completely resected NSCLC with pathological Stage I. Overall 5-year survival and disease-free survival showed a promising trend . Treatment-related toxicity is acceptable Among patients with lung cancer approximately 44 % have disease limited to the chest . Patients with early lesions treated surgically have better survival rates than those with more advanced primary disease or nodal involvement . Postoperative irradiation should reduce local or regional recurrence and hopefully reduce systemic relapse OBJECTIVE Although surgical resection alone is considered adequate treatment in stage IB non-small-cell lung cancer ( NSCLC ) , long-term survival is not satisfactory and the recurrence rate is quite high . The validity of postoperative chemotherapy at stage IB in terms of disease-free and overall survival was assessed in a r and omised trial . METHODS The trial was design ed as a r and omised , two-group study with postoperative adjuvant chemotherapy versus surgery alone as control group . All patients had stage IB disease ( pT2N0 ) assessed after a radical surgical procedure .  Chemotherapy consisted of treatment with cisplatin ( 100 mg/m(2 ) on day 1 ) and etoposide ( 120 mg/m(2 ) on days 1 - -3 ) for a total of six cycles . RESULTS Between January 1988 and December 1994 , 66 patients were included in the study . Thirty-three belonged to the adjuvant chemotherapy group and 33 to the control group . Groups were homogeneous for conventional risk factors . There was no clinical significant morbidity associated to chemotherapy . Patients were followed for a minimum period of 5 years . The rates of locoregional recurrence and distant metastases were 18 and 30 % , respectively , in the adjuvant chemotherapy group and 24 and 43 % , respectively , in the control group . The 5-year disease-free survival rates were 59 % in the adjuvant group and 30 % in the control group ( P = 0.02 ) . The difference in the Kaplan -- Meier survival between the groups was significant as assessed using the log-rank test ( P = 0.04 ) . CONCLUSIONS Our results suggest that adjuvant chemotherapy may reduce recurrences and prolong overall survival in patients at stage IB NSCLC deemed radically operated . Despite being difficult to accept , the use of adjuvant chemotherapy might have better long-term results We r and omly assigned 230 patients with resected Stage II or III epidermoid ( squamous-cell ) lung cancer to receive postoperative adjuvant radiotherapy or no adjuvant treatment . Careful intraoperative staging had been performed in all patients . Before r and omization , patients were stratified according to stage , weight loss , age , and institution . Prognostic variables , such as stage , weight loss , age , nodal-disease status , and tumor status , were equally distributed between the two groups . The mean time from r and omization to analysis was 3.5 years among the 210 eligible patients . There was no evidence that radiotherapy improved survival , and although recurrence rates appeared to be somewhat reduced among patients assigned to radiotherapy , these decreases were not statistically significant . However , radiotherapy did produce a striking and significant reduction in recurrences to the ipsilateral lung and mediastinum . Moreover , overall recurrence rates were reduced by radiotherapy in patients with N2 disease ( P less than 0.05 ) , although even this subgroup had no evidence of improved survival . We conclude that radiotherapy can reduce local recurrences after resection of epidermoid carcinoma of the lung , but that it does not increase survival rates In the period 1988 - 1992 , 74 consecutive radically resected patients with NSCLC were r and omised to postoperative radiotherapy or surgery alone in order to evaluate the influence of postoperative radiotherapy on survival . There were 61 males and 13 females , aged 35 - 80 years , median 59 years . Their distribution by stage was as follows : pT1N2 = 19 , pT2N2 = 54 , pT3N2 = one patient ; histology : 32 squamous , 32 adeno and 10 large cell carcinomas ; surgery : atypical resection in six , lobectomy in 27 , bilobectomy in ten , and pneumonectomy in 31 patients . In 27 patients , only one lymph node in a single mediastinal lymph node site was affected ; in 31 patients more than one lymph node in one site ; in 16 patients more sites were affected . In 35/74 patients radiotherapy of hilar and mediastinal sites with 3000 cGy in 2 weeks was performed . On December 31 , 1994 , 19 patients ( 26 % ) were still alive ; 39/55 patients died of the following causes : locoregional failure-10(26 % ) , distant metastases- 25 ( 64 % ) , other tumor-unrelated causes-four patients ( 10 % ) . Five-year survival rates did not show statistically significant differences between the irradiated and surgically treated patients only with respect to sex , pTNM stage , histology and frequency of locoregional failure . The number of metastatic mediastinal lymph nodes was the only significant prognostic factor ( P < 0.005 ) in both r and omised groups PURPOSE To evaluate the value of adjuvant postoperative external-beam radiation ( EBR ) in patients with radically resected non-small cell lung cancer ( NSCLC ) pT1 - 3 pN0 - 2 compared to patients with resected NSCLC without adjuvant EBR . MATERIAL S AND METHODS In 155 patients ( 121 male , 34 female ; mean age , 59 years ) 105 lobectomies , 12 bilobectomies , and 38 pneumonectomies with radical lymph node dissection of the contralateral [ corrected ] side were performed . Postoperative staging was done according to the TNM system and was as follows : pT1 ( n=38 ) , pT2 ( n=89 ) , pT3 ( n=28 ) ; pN0 ( n=39 ) , pN1 ( n=67 ) and pN2 ( n=49 ) . Histopathologic study revealed 68 squamous cell carcinomas , 53 adenocarcinomas , 21 large cell carcinomas , 6 adenosquamous cell carcinomas , and 7 bronchioloalveolar cell carcinomas . All patients were r and omly assigned into two treatment groups : 72 patients with no further treatment ( control group ) , and 83 patients ( EBR group ) with adjuvant postoperative EBR of the bronchial stump and mediastinum ( 50 to 56 Gy , 8 or 23 MV photons , 2 Gy/d , 5 d/wk ) beginning 4 to 6 weeks after surgery . RESULTS The overall 5-year survival rate ( median observation time , 43 months ) of all patients was 24.1 % ( EBR group , 29.7 % ; control group , 20.4 % ; p>0.05 , not significant ) . The relative risk of the EBR group was 0.85 with a two-sided confidence interval of 0.66 to 1.09 . The overall 5-year recurrence-free survival was 20.6 % ( EBR , 27.1 % ; control group , 15.6 % ; p=0.07 ) . The relative risk of the EBR group was 0.80 with a confidence interval of 0.63 to 1.01 . The rate of local recurrences at the bronchial stump and /or mediastinum was significantly smaller in the EBR group ( n=5 ) than in the control group ( n=17 ) ( p<0.01 ) . Multivariate analysis ( chi2 test ) demonstrated an independent influence of postoperative EBR on the incidence of local recurrences . The incidence of distant metastases was slightly but not significantly higher in patients without EBR ( 38 patients ) compared to those who had EBR ( 32 patients ) . CONCLUSION High-dose postoperative EBR to the mediastinum significantly reduces the risk of local recurrence at the bronchial stump and /or mediastinum . Age , sex , histologic subtype , tumor size , surgical approach , or extent of lymph node involvement had no prognostic value -- only postoperative EBR had an independent influence on the risk of local recurrence . The effect of postoperative EBR was on the verge of significance with respect to recurrence-free survival and showed the same tendency in overall survival , however with an attenuated relative risk Abstract Postoperative supervoltage radiotherapy was tested in a controlled clinical trial in an attempt to improve the survival for patients with bronchogenic carcinoma .  Radiation therapy began 3 to 4 weeks after surgery ; three fields were used giving a dose of 6,000 rad in six weeks to the mediastinum from a Co 60 unit . Between 1966 and 1975 , 224 patients were included in this study . All had a resection of curative design . 175 patients were evaluable . No increase in survival time was noticed in the irradiated group . The 5 year survival rate was lower in this group ( 24 % versus 43 % for the control group ) but the difference was not statistically significant . For squamous cell carcinoma , the analysis showed a detrimental effect of radiation therapy in the T 2 group ( PURPOSE To study the value of postoperative radiotherapy for non-small-cell lung cancer ( NSCLC ) with positive regional lymph metastases ( NI or N2 ) after radical surgery . MATERIAL S AND METHODS From February 1982 to October 1995 , 366 patients with NSCLC and N1 or N2 disease were r and omized into  postoperative radiotherapy ( S + R ) ( 183 patients ) and no further treatment ( S alone ) ( 182 patients ) . Postoperative radiotherapy ( RT ) was administrated 3 - 4 weeks after radical operation . Irradiated fields covered the bronchial stump , ipsilateral hilum , and most of the mediastinum . The midplane dose was 6000 cGy/30 fractions/6 weeks , with the spinal cord limited to 4000 cGy/20 fractions/4 weeks or less . One hundred thirty-four patients in S + R group and 162 patients in S alone group were evaluated . Clinical data were comparable in both arms , except for the numbers of N2 patients . RESULTS The 3-year and 5-year overall surv 
    Output:
    
agent
***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: The role of post-operative radiotherapy for patients with non-small-cell lung cancer ( NSCLC ) is unclear despite five previous r and omised trials . One deficiency with these trials was that they did not include adequate TNM staging , and so the present r and omised trial was design ed to compare surgery alone ( S ) with surgery plus post-operative radiotherapy ( SR ) in patients with pathologically staged T1 - 2 , N1 - 2 . M0 NSCLC . Between July 1986 and October 1993 , 308 patients ( 154 S , 154 SR ) were entered from 16 centres in the UK . The median age of the patients was 62 years , 74 % were male , > 85 % had normal or near normal levels of general condition , activity and breathlessness , 68 % had squamous carcinoma , 52 % had had a pneumonectomy , 63 % had N1 disease and 37 % N2 disease . SR patients received 40 Gy in 15 fractions starting 4 - 6 weeks post-operatively . Overall there was no advantage to either group in terms of survival , although definite local recurrence and bony metastases appeared less frequently and later in the SR group . In a subgroup analysis , in the N1 group no differences between the treatment groups were seen , but in the N2 group SR patients appeared to gain a one month survival advantage , delayed time to local recurrence and time to appearance of the bone metastases . There is , therefore , no clear indication for post-operative radiotherapy in N1 disease , but the question remains unresolved in N2 disease BACKGROUND AND PURPOSE To evaluate the benefits and the drawbacks of post-operative radiotherapy in completely resected Stage I ( a and b ) non-small cell lung cancer ( NSCLC ) . MATERIAL S AND METHODS Patients with pathological Stages Ia and Ib NSCLC have been r and omized into two groups : Group 1 ( G1 ) received adjuvant radiotherapy , Group 0 ( G0 ) the control group did not receive any adjuvant therapy .  Local control , toxicity and survival have been evaluated . RESULTS Between July 1989 and June 1997 , 104 patients with pathological stage I NSCLC have been enrolled in this study . Fifty-one patients were r and omized to G1 and 53 to G0 . Six patients have been excluded from the study due to incomplete follow-up data . Regarding local control , one patient in the G1 group had a local recurrence ( 2.2 % ) while in the G0 12 local recurrences have been observed ( 23 % ) . Seventy-one percent of patients are disease-free at 5 years in G1 and 60 % in G0 ( P=0.039 ) . Overall 5-year survival ( Kaplan-Meier ) showed a positive trend in the treated group : 67 versus 58 % ( P=0.048 ) . Regarding toxicity in G1 , six patients experienced a grade 1 acute toxicity . Radiological evidence of long-term lung toxicity , with no significant impairment of the respiratory function , has been detected in 18 of the 19 patients who have been diagnosed as having a post-radiation lung fibrosis . CONCLUSIONS Adjuvant radiotherapy gave good results in terms of local control in patients with completely resected NSCLC with pathological Stage I. Overall 5-year survival and disease-free survival showed a promising trend . Treatment-related toxicity is acceptable Among patients with lung cancer approximately 44 % have disease limited to the chest . Patients with early lesions treated surgically have better survival rates than those with more advanced primary disease or nodal involvement . Postoperative irradiation should reduce local or regional recurrence and hopefully reduce systemic relapse OBJECTIVE Although surgical resection alone is considered adequate treatment in stage IB non-small-cell lung cancer ( NSCLC ) , long-term survival is not satisfactory and the recurrence rate is quite high . The validity of postoperative chemotherapy at stage IB in terms of disease-free and overall survival was assessed in a r and omised trial . METHODS The trial was design ed as a r and omised , two-group study with postoperative adjuvant chemotherapy versus surgery alone as control group . All patients had stage IB disease ( pT2N0 ) assessed after a radical surgical procedure .  Chemotherapy consisted of treatment with cisplatin ( 100 mg/m(2 ) on day 1 ) and etoposide ( 120 mg/m(2 ) on days 1 - -3 ) for a total of six cycles . RESULTS Between January 1988 and December 1994 , 66 patients were included in the study . Thirty-three belonged to the adjuvant chemotherapy group and 33 to the control group . Groups were homogeneous for conventional risk factors . There was no clinical significant morbidity associated to chemotherapy . Patients were followed for a minimum period of 5 years . The rates of locoregional recurrence and distant metastases were 18 and 30 % , respectively , in the adjuvant chemotherapy group and 24 and 43 % , respectively , in the control group . The 5-year disease-free survival rates were 59 % in the adjuvant group and 30 % in the control group ( P = 0.02 ) . The difference in the Kaplan -- Meier survival between the groups was significant as assessed using the log-rank test ( P = 0.04 ) . CONCLUSIONS Our results suggest that adjuvant chemotherapy may reduce recurrences and prolong overall survival in patients at stage IB NSCLC deemed radically operated . Despite being difficult to accept , the use of adjuvant chemotherapy might have better long-term results We r and omly assigned 230 patients with resected Stage II or III epidermoid ( squamous-cell ) lung cancer to receive postoperative adjuvant radiotherapy or no adjuvant treatment . Careful intraoperative staging had been performed in all patients . Before r and omization , patients were stratified according to stage , weight loss , age , and institution . Prognostic variables , such as stage , weight loss , age , nodal-disease status , and tumor status , were equally distributed between the two groups . The mean time from r and omization to analysis was 3.5 years among the 210 eligible patients . There was no evidence that radiotherapy improved survival , and although recurrence rates appeared to be somewhat reduced among patients assigned to radiotherapy , these decreases were not statistically significant . However , radiotherapy did produce a striking and significant reduction in recurrences to the ipsilateral lung and mediastinum . Moreover , overall recurrence rates were reduced by radiotherapy in patients with N2 disease ( P less than 0.05 ) , although even this subgroup had no evidence of improved survival . We conclude that radiotherapy can reduce local recurrences after resection of epidermoid carcinoma of the lung , but that it does not increase survival rates In the period 1988 - 1992 , 74 consecutive radically resected patients with NSCLC were r and omised to postoperative radiotherapy or surgery alone in order to evaluate the influence of postoperative radiotherapy on survival . There were 61 males and 13 females , aged 35 - 80 years , median 59 years . Their distribution by stage was as follows : pT1N2 = 19 , pT2N2 = 54 , pT3N2 = one patient ; histology : 32 squamous , 32 adeno and 10 large cell carcinomas ; surgery : atypical resection in six , lobectomy in 27 , bilobectomy in ten , and pneumonectomy in 31 patients . In 27 patients , only one lymph node in a single mediastinal lymph node site was affected ; in 31 patients more than one lymph node in one site ; in 16 patients more sites were affected . In 35/74 patients radiotherapy of hilar and mediastinal sites with 3000 cGy in 2 weeks was performed . On December 31 , 1994 , 19 patients ( 26 % ) were still alive ; 39/55 patients died of the following causes : locoregional failure-10(26 % ) , distant metastases- 25 ( 64 % ) , other tumor-unrelated causes-four patients ( 10 % ) . Five-year survival rates did not show statistically significant differences between the irradiated and surgically treated patients only with respect to sex , pTNM stage , histology and frequency of locoregional failure . The number of metastatic mediastinal lymph nodes was the only significant prognostic factor ( P < 0.005 ) in both r and omised groups PURPOSE To evaluate the value of adjuvant postoperative external-beam radiation ( EBR ) in patients with radically resected non-small cell lung cancer ( NSCLC ) pT1 - 3 pN0 - 2 compared to patients with resected NSCLC without adjuvant EBR . MATERIAL S AND METHODS In 155 patients ( 121 male , 34 female ; mean age , 59 years ) 105 lobectomies , 12 bilobectomies , and 38 pneumonectomies with radical lymph node dissection of the contralateral [ corrected ] side were performed . Postoperative staging was done according to the TNM system and was as follows : pT1 ( n=38 ) , pT2 ( n=89 ) , pT3 ( n=28 ) ; pN0 ( n=39 ) , pN1 ( n=67 ) and pN2 ( n=49 ) . Histopathologic study revealed 68 squamous cell carcinomas , 53 adenocarcinomas , 21 large cell carcinomas , 6 adenosquamous cell carcinomas , and 7 bronchioloalveolar cell carcinomas . All patients were r and omly assigned into two treatment groups : 72 patients with no further treatment ( control group ) , and 83 patients ( EBR group ) with adjuvant postoperative EBR of the bronchial stump and mediastinum ( 50 to 56 Gy , 8 or 23 MV photons , 2 Gy/d , 5 d/wk ) beginning 4 to 6 weeks after surgery . RESULTS The overall 5-year survival rate ( median observation time , 43 months ) of all patients was 24.1 % ( EBR group , 29.7 % ; control group , 20.4 % ; p>0.05 , not significant ) . The relative risk of the EBR group was 0.85 with a two-sided confidence interval of 0.66 to 1.09 . The overall 5-year recurrence-free survival was 20.6 % ( EBR , 27.1 % ; control group , 15.6 % ; p=0.07 ) . The relative risk of the EBR group was 0.80 with a confidence interval of 0.63 to 1.01 . The rate of local recurrences at the bronchial stump and /or mediastinum was significantly smaller in the EBR group ( n=5 ) than in the control group ( n=17 ) ( p<0.01 ) . Multivariate analysis ( chi2 test ) demonstrated an independent influence of postoperative EBR on the incidence of local recurrences . The incidence of distant metastases was slightly but not significantly higher in patients without EBR ( 38 patients ) compared to those who had EBR ( 32 patients ) . CONCLUSION High-dose postoperative EBR to the mediastinum significantly reduces the risk of local recurrence at the bronchial stump and /or mediastinum . Age , sex , histologic subtype , tumor size , surgical approach , or extent of lymph node involvement had no prognostic value -- only postoperative EBR had an independent influence on the risk of local recurrence . The effect of postoperative EBR was on the verge of significance with respect to recurrence-free survival and showed the same tendency in overall survival , however with an attenuated relative risk Abstract Postoperative supervoltage radiotherapy was tested in a controlled clinical trial in an attempt to improve the survival for patients with bronchogenic carcinoma .  Radiation therapy began 3 to 4 weeks after surgery ; three fields were used giving a dose of 6,000 rad in six weeks to the mediastinum from a Co 60 unit . Between 1966 and 1975 , 224 patients were included in this study . All had a resection of curative design . 175 patients were evaluable . No increase in survival time was noticed in the irradiated group . The 5 year survival rate was lower in this group ( 24 % versus 43 % for the control group ) but the difference was not statistically significant . For squamous cell carcinoma , the analysis showed a detrimental effect of radiation therapy in the T 2 group ( PURPOSE To study the value of postoperative radiotherapy for non-small-cell lung cancer ( NSCLC ) with positive regional lymph metastases ( NI or N2 ) after radical surgery . MATERIAL S AND METHODS From February 1982 to October 1995 , 366 patients with NSCLC and N1 or N2 disease were r and omized into  postoperative radiotherapy ( S + R ) ( 183 patients ) and no further treatment ( S alone ) ( 182 patients ) . Postoperative radiotherapy ( RT ) was administrated 3 - 4 weeks after radical operation . Irradiated fields covered the bronchial stump , ipsilateral hilum , and most of the mediastinum . The midplane dose was 6000 cGy/30 fractions/6 weeks , with the spinal cord limited to 4000 cGy/20 fractions/4 weeks or less . One hundred thirty-four patients in S + R group and 162 patients in S alone group were evaluated . Clinical data were comparable in both arms , except for the numbers of N2 patients . RESULTS The 3-year and 5-year overall surv 
    Output:
    