***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: Between January 1986 and December 1992 , sixty-nine patients with squamous esophageal cancer were r and omized to one or the other of two treatment groups . Group 1 ( 35 patients ) were scheduled to receive chemotherapy ( cisplatinum and 5-fluorouracil ) and radiation , followed by resection , while group 2 ( 34 patients ) received resection alone . Of the 35 patients entering combined treatment , 26 completed the protocol and 9 received only chemoradiation . A complete response to preoperative therapy was shown by 7 patients , and a partial response by the other 7 patients . Survival rates at one year and five years were slightly better among patients receiving combined treatment than among those undergoing surgery alone , but overall survival did not differ statistically between the two groups . Nor were operative mortality and complications statistical different between the two groups OBJECTIVE Induction chemoradiotherapy followed by surgery may improve survival rates among patients with esophageal carcinoma . We design ed a novel intense induction regimen with paclitaxel and high-dose hyperfractionated radiotherapy to maximize complete response rates . METHODS Forty patients with esophageal cancer were treated in a phase I and II trial of induction chemotherapy ( cisplatin , 5-fluorouracil , and paclitaxel ) at three dosage levels ( 75 , 125 , and 100 mg/m2 ) and concurrent hyperfractionated radiotherapy ( 45 Gy to the mediastinum , 58.5 Gy to the tumor ) . The mean age was 62 years , and 32 patients ( 80 % ) had adenocarcinoma . Twenty-eight of 40 ( 70 % ) patients had locally advanced tumors ( T3 , or stage IIB or greater ) . RESULTS The average hospitalization for induction treatment was 17 days . Toxicity was substantial , with esophagitis necessitating nutritional support the most common complication . The maximum tolerated dose of  paclitaxel  was 100 mg/m2 . Two patients died during induction treatment . Thirty-six patients ( 90 % ) underwent resection . The median length of stay was 10 days , and two patients died after the operation . Fourteen of 36 patients ( 39 % ) had a pathologic complete response . Patients who received all prescribed chemotherapy had a higher pathologic complete response rate ( 50 % ) than did patients who required dose reduction ( 17 % ; p = 0.076 ) . The 2-year survival rate was 61 % ( 95 % CI 35 % to 86 % ) with a median follow-up of 11.9 months . CONCLUSIONS Paclitaxel at a dose of 100 mg/m2 appears to have acceptable toxicity . The high pathologic complete response rate in this regimen is encouraging , but it is associated with substantial toxicity . The toxicity of this regimen is not acceptable and will require substantial reduction in the radiation component . Survival data are too short-term to confirm enhanced survival OBJECTIVE Different types of multimodality therapy , including chemoradiotherapy and surgery , increasingly are being used for the treatment of patients with locally advanced non-small cell lung cancer ( NSCLC ; stages IIIA and IIIB ) . In this context , the applicability of a morphologic regression grading and its prognostic value were investigated . PATIENTS AND METHODS In a multicenter phase II trial , 54 patients with locally advanced NSCLC received neoadjuvant bimodality treatment ( ie , two cycles of ifosfamide , carboplatin , and etoposide , followed by twice-daily radiation up to 45 Gy with simultaneous administration of carboplatin and vindesine ) . Forty patients underwent resections . Using the corresponding resection specimens of the primary and regional lymph nodes , the following regression grading was established : grade I , no regression or only spontaneous tumor regression ; grade II , morphologic evidence of therapy-induced tumor regression with at least 10 % ( grade IIa ) or < 10 % ( grade IIb ) vital tumor tissue ; and grade III , complete tumor regression with no evidence of vital tumor tissue . Regression grading then was correlated with the survival time . RESULTS Three tumors were classified as regression grade I , 10 were classified as regression grade IIa , 20 were classified as regression grade IIb , and 7 were classified as regression grade III . Patients with tumors of regression grade s IIb or III showed significantly longer survival times than those with tumors of regression grade s I or IIa ( median survival time , 36 vs 14 months , respectively ; 3-year survival rate , 52 % vs 9 % , respectively ; p = 0.02 ) . These survival times were also compared for patients who had undergone complete resection ( median survival time , not reached vs 23 months , respectively ; 3-year survival rate , 56 % vs 11 % , respectively ; p = 0.03 ) . The presurgical clinical response after patients had received neoadjuvant multimodality therapy had no predictive value in assessing the extent of therapy-induced tumor regression in the resection specimen . CONCLUSIONS After neoadjuvant therapy of patients with NSCLC , the proposed tumor regression grading was of predictive value for long-term survival . Beyond the achievement of complete tumor resection ( R0 ) , a therapy-induced tumor regression of < 10 % of vital tumor tissue is pivotal for superior long-term outcomes Background . Despite well‐established surgical approaches , the prognosis for patients with squamous cell carcinoma of the esophagus remains dismal . To assess the benefit of adjuvant chemotherapy and radiation therapy ( CRT ) , a r and omized trial with and without sequential preoperative CRT was undertaken ; CRT combined 20 Gy and two courses of 5‐FU and cisplatin BACKGROUND We conducted a multicenter , r and omized trial to compare preoperative chemoradiotherapy followed by surgery with surgery alone in patients with stage I and II squamous-cell cancer of the esophagus . METHODS The preoperative combined therapy consisted of two one-week courses ; each involved radiotherapy , in a dose of 18.5 Gy delivered in five fractions of 3.7 Gy each , and 80 mg of cisplatin per square meter of body-surface area , administered 0 to 2 days before the first day of radiotherapy . The surgical plan included one-stage en bloc esophagectomy and proximal gastrectomy by the abdominal and right thoracic routes , to be performed immediately after r and omization in the group assigned to surgery alone and two to four weeks after the completion of preoperative chemoradiotherapy in the group assigned to combined therapy . RESULTS A total of 297 patients entered the study ; 11 were found to be ineligible , and 4 were lost to follow-up . Of the remaining 282 , 139 were assigned to surgery alone and 143 to combined therapy . After a median follow-up of 55.2 months , no significant difference in overall survival was observed ; the median survival was 18.6 months for both groups . As compared with the group treated with surgery alone , the group treated preoperatively had longer disease-free survival ( P=0.003 ) , a longer interval free of local disease ( P=0.01 ) , a lower rate of cancer-related deaths ( P=0.002 ) , and a higher frequency of curative resection ( P=0.017 ) . However , there were more postoperative deaths ( P=0.012 ) in the group treated preoperatively with chemoradiotherapy . Three prognostic factors were found to influence survival in a multivariate analysis : the disease stage , based on computed tomography ; the location of the tumor ; and whether the surgical resection was curative . CONCLUSIONS In patients with squamous-cell esophageal cancer , preoperative chemoradiotherapy did not improve overall survival , but it did prolong disease-free survival and survival free of local disease PURPOSE To conduct a multicenter phase II study of a concomitant combination of chemotherapy and radiotherapy followed by surgery , where feasible , in patients with nonmetastatic esophageal tumor , stratified on operability at diagnosis . METHODS Each cycle consisted of fluorouracil ( 5FU ) 800 mg/m2/d by continuous intravenous ( IV ) infusion on days 1 to 5 , cisplatin ( CDDP ) 50 mg/m2/d IV bolus on days 1 and 8 , hydroxyurea ( HU ) 1.5 or 2 g/d orally on days 8 to 12 and concomitant radiotherapy 20 Gy in 10 fractions over 12 days . All patients were to receive two cycles on days 1 and 22 . If feasible , surgery was performed 3 to 6 weeks after cycle two completion . Otherwise , a third cycle was administered . RESULTS Eighty-eight patients were included between September 1990 and September 1993 . Of the 47 operable patients , 41 ( 87 % ) underwent surgery and 38 ( 81 % ) had a complete resection . No residual primary tumor was found in the surgical specimen in 17 cases ( 36 % ) , and only microscopic foci in 13 ( 28 % ) . Two-year overall and disease-free survival probabilities were 51 % ( 95 % confidence interval [ CI ] ; 37 to 65 ) and 43 % ( 95 % CI , 28 to 57 ) , respectively . Among the 41 inoperable patients , 12 ( 29 % ) became operable . Seven ( 17 % ) had complete resection , two incomplete resection , and three exploratory surgery . Two-year overall and disease-free survival probabilities were 29 % ( 95 % CI , 15 to 43 ) and 27 % ( 95 % CI , 13 to 40 ) , respectively . Five deaths occurred during chemoradiotherapy , six postoperatively and four in patients with evidence of cancer . Five late complications ( one myelopathy ) were observed . CONCLUSION Despite a high histologic response rate in initially operable patients , overall survival was similar to that observed in other preoperative chemoradiation series because of substantial toxicity PURPOSE The primary treatment modality for patients with carcinoma of the esophagus or gastroesophageal junction has been surgery , although primary radiation therapy with concurrent chemotherapy produces similar results . As both have curative potential , there has been great interest in the use of trimodality therapy . To this end , we compared survival , response , and patterns of failure of trimodality therapy to esophagectomy alone in patients with nonmetastatic esophageal cancer . PATIENTS AND METHODS Four hundred seventy-five eligible patients were planned for enrollment . Patients were r and omly assigned to either esophagectomy with node dissection alone or cisplatin 100 mg/m(2 ) and fluorouracil 1,000 mg/m(2)/d for 4 days on weeks 1 and 5 concurrent with radiation therapy ( 50.4 Gy total : 1.8 Gy/fraction over 5.6 weeks ) followed by esophagectomy with node dissection . RESULTS Fifty-six patients were enrolled between October 1997 and March 2000 , when the trial was closed due to poor accrual . Thirty patients were r and omly assigned to trimodality therapy and 26 were assigned to surgery alone . Patient and tumor characteristics were similar between groups . Treatment was generally well tolerated . Median follow-up was 6 years . An intent-to-treat analysis showed a median survival of 4.48 v 1.79 years in favor of trimodality therapy ( exact stratified log-rank , P = .002 ) . Five-year survival was 39 % ( 95 % CI , 21 % to 57 % ) v 16 % ( 95 % CI , 5 % to 33 % ) in favor of trimodality therapy . CONCLUSION The results from this trial reflect a long-term survival advantage with the use of chemoradiotherapy followed by surgery in the treatment of esophageal cancer , and support trimodality therapy as a st and ard of care for patients with this disease Objective : We present and analyze long-term outcomes following multimodal therapy for esophageal cancer , in particular the relative impact of histomorphologic tumor regression and nodal status . Patients and Methods : A total of 243 patients [ ( adenocarcinoma ( n = 170 ) and squamous cell carcinoma ( n = 73 ) ] treated with neoadjuvant chemoradiotherapy in the period 1990 to 2004 were followed prospect ively with a median follow-up of 60 months . Pathologic stage and tumor regression grade ( TRG ) were documented , the site of first failure was recorded , and Kaplan-Meier survival curves were plotted . Results : Thirty patients ( 12 % ) did not undergo surgery due to disease progression or deteriorated performance status . Forty-one patients ( 19 % ) had a complete pathologic response ( pCR ) , and there were 31(15 % ) stage I , 69 ( 32 % ) stage II , and 72 ( 34 % ) stage III cases . The overall median survival was 18 months , and the 5-year survival was 27 % . The 5-year survival of patients achieving a pCR was 50 % compared with 37 % in non-pCR patients who were node-negative ( P = 0.86 ) . Histomorphologic tumor regression was not associated with pre-CRT cTN stage but was significantly ( P < 0.05 ) associated with ypN stage . By multivariate analysis , ypN 
    Output:
    
Analyzing only the applied dose of radiation demonstrated that patients with AC required a higher dose than patients with SCC to achieve complete response .
Incorporating chemotherapy administration does not markedly change the difference in required radiation dose .
However , when the tumor does respond , the rate of pCR with increasing dosage of chemoradiotherapy increases more rapidly in AC patients than in SCC patients