***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 
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    Input: OBJECTIVE : The objective of this study was to identify the risk factors for delays in chemotherapy after rectal cancer surgery and evaluate the effects of delayed therapy on long-term outcomes . We also sought to clarify what time frame should be used to define delayed adjuvant chemotherapy . BACKGROUND : Postoperative complications have been found to influence the timing of chemotherapy in patients with colon cancer . Delays in chemotherapy have been shown to be associated with worse overall and disease-free survival in patients with colorectal cancer , although the timing of delay has not been agreed upon in the literature . STUDY DESIGN : We performed a retrospective review of a prospect ively maintained rectal cancer data base . Univariate analysis was used to identify risk factors for delayed chemotherapy . Kaplan-Meier curves were generated to compare overall and disease-free survival in patients based on complications and timing of chemotherapy . SETTING S : This study was performed at the University of Wisconsin Hospital , Madison , Wisconsin , between 1995 and 2012 . PATIENTS : Patients with rectal cancer who underwent proctectomy with curative intent were included in this study . OUTCOME MEASURES : Timing of chemotherapy , 30-day complications , and 30-day readmissions were the main outcome measures . RESULTS : Postoperative complications and 30-day readmissions were associated with delays in chemotherapy ≥8 weeks after surgery . Patients who received chemotherapy ≥8 weeks postoperatively were found to have worse local and distant recurrence rates and worse overall survival in comparison with patients who received chemotherapy within 8 weeks of surgery . LIMITATIONS : The limitations of this study include its retrospective nature and that it was performed at a single institution . CONCLUSIONS : We found complications and readmissions to be risk factors for delayed chemotherapy . Patients who received therapy ≥8 weeks postoperatively had worse disease-free and overall survival BACKGROUND Whether adjuvant chemotherapy improves survival of patients with non-small-cell lung cancer ( NSCLC ) is not known . We aim ed to compare the effect of adjuvant vinorelbine plus cisplatin versus observation on survival in patients with completely resected NSCLC . METHODS 840 patients with stage IB-IIIA NSCLC from 101 centres in 14 countries were r and omly assigned to observation ( n=433 ) or to 30 mg/m(2 ) vinorelbine plus 100 mg/m(2 ) cisplatin ( n=407 ) . Postoperative radiotherapy was not m and atory and was undertaken according to every centre 's policy . The primary endpoint was overall survival . Analysis was by intention to treat . This trial is registered as an International St and ard R and omised Controlled Trial , number IS RCT N95053737 . FINDINGS 367 patients in the chemotherapy group and 431 in the control group received their assigned treatment . 301 ( 36 % ) patients had stage IB disease , 203 ( 24 % ) had stage II disease , and 325 ( 39 % ) had stage IIIA disease . Tolerance to chemotherapy mainly included neutropenia in 335 ( 92 % ) patients and febrile neutropenia in 34 ( 9 % ) ; seven ( 2 % ) toxic deaths were also recorded . Compliance was greater with cisplatin than with vinorelbine ( median dose intensity 89 % [ range 17 - 108 ] vs 59 % [ 17 - 100 ] ) . After a median follow-up of 76 months ( range 43 - 116 ) , median survival was 65.7 months ( 95 % CI 47.9 - 88.5 ) in the chemotherapy group and 43.7 ( 35.7 - 52.3 ) months in the observation group . Adjusted risk for death was significantly reduced in patients assigned chemotherapy compared with controls ( hazard ratio 0.80 [ 95 % CI 0.66 - 0.96 ] ; p=0.017 ) . Overall survival at 5 years with chemotherapy improved by 8.6 % , which was maintained at 7 years ( 8.4 % ) . INTERPRETATION Adjuvant vinorelbine plus cisplatin extends survival in patients with completely resected NSCLC , better defining indication of adjuvant chemotherapy We report a single-centre prospect i ve audit of 29 lung cancer patients who were awaiting radical ( potentially curative ) radiotherapy .  This was the total number assessed as suitable for radical treatment by one consultant during 1999 . At the time of assessment they had been newly diagnosed and staged with a computed tomographic ( CT ) scan of chest . They had a subsequent CT scan prior to starting treatment for the purpose of planning the radiation fields . We have now measured tumour size on the diagnostic scans and compared this with the size on the planning scans . We have documented the delay between diagnostic and planning CT scanning and the total time between first hospital visit and starting treatment . Two patients had progression of symptoms while on the waiting list , making them unfit for radical treatment , and another four had tumour progression on planning CT such that the tumour volume was too large for radical treatment . Therefore , 21 % of potentially curable patients became incurable on the waiting list . The delay between diagnostic and planning CT scans ranged from 18 to 131 days ( median 54 ) , with increases in the cross-sectional tumour size over that period ranging zero to 373 % . The delay between the first hospital visit and starting treatment was 35 - 187 days ( median 94 ) ; between the date of the radiotherapy request and the starting date for treatment it was 23 - 61 days ( median 44 ) . Limited access to specialists is the reason most often advanced for the poor performance of the UK in treating lung cancer . This study demonstrates that , even for the select minority of patients who have specialist referral and are deemed suitable for potentially curative treatment , the outcome is prejudiced by waiting times that allow tumour progression The purpose of this study was to examine the effect on survival of delaying the start of adjuvant chemotherapy for early breast cancer for up to 3 months after surgery . In the nation-wide clinical trials of the Danish Breast Cancer Cooperative Group , 7501 breast cancer patients received chemotherapy within 3 months of surgery between 1977 and 1999 : 352 with classical cyclofosfamide , metotrexate and 5-fluorouracil ( CMF ) ; 6065 with CMF i.v . and 1084 with cyclofosfamide , epirubicin and 5-fluorouracil . For the analysis , the time between surgery and the start of chemotherapy was divided into four strata ( 1–3 , 4 , 5 and 6–13 weeks ) . The results show that within the three groups of chemotherapy , there was an even distribution of known prognostic factors across the four strata of initiation of chemotherapy . There was no pattern indicating a benefit from early start of chemotherapy . No significant interactions were found for subgroups of patients with a poorer prognosis ( many involved lymph nodes , high- grade malignancies or hormone receptor negative disease ) . In conclusion , we have found no evidence for a survival benefit due to early initiation of adjuvant chemotherapy within the first 2–3 months after surgery PURPOSE Theoretically , patients with early breast cancer might benefit from starting adjuvant chemotherapy soon after surgery , and this would have important clinical implication s. We have addressed this question from a large , single-center data base in which the majority of patients received anthracyclines . PATIENTS AND METHODS A total of 1161 patients from a prospect ively maintained data base treated with adjuvant chemotherapy for early breast cancer at the Royal Marsden Hospital ( London , United Kingdom ) , including 686 ( 59 % ) receiving anthracyclines , were retrospectively analyzed . The disease-free survival ( DFS ) and overall survival ( OS ) of the 368 patients starting chemotherapy within 21 days of surgery ( group A ) were compared with those of the 793 patients commencing chemotherapy > or= 21 days after surgery ( group B ) . Median follow-up time was 39 months ( range , 12 to 147 months ) . RESULTS No significant difference in 5-year DFS was found between the two groups overall ( 70 % for group A v 72 % for group B ; P = .4 ) or in any subgroup . Likewise , there was no difference in 5-year OS ( 82 % for group A v 84 % for group B ; P = .2 ) or when the interval to the start of chemotherapy was considered as a continuous variable ( P = .4 ) . CONCLUSION We have been unable to identify any significant survival benefit from starting adjuvant chemotherapy early after surgery , either overall or in any subset of patients BACKGROUND Neither chemotherapy with a single-alkylating agent nor aggressive combination chemotherapy cures advanced stage low- grade non-Hodgkin lymphomas , even when combined with radiotherapy . Our aim was to compare administration of immediate chlorambucil treatment with a policy of delaying chlorambucil until clinical progression necessitated its use , in asymptomatic patients with advanced-stage , low- grade non-Hodgkin lymphoma . METHODS 309 patients with asymptomatic , advanced-stage , low- grade non-Hodgkin lymphomas were recruited from 44 UK centres between Feb 1 , 1981 , and July 31 , 1990 . 158 patients were r and omised to receive immediate systemic therapy with oral chlorambucil 10 mg per day continuously . The remaining 151 were r and omised to an initial policy of observation , with systemic therapy delayed until disease progression . In both groups , local radiotherapy to symptomatic nodes was allowed . FINDINGS Median length of follow-up was 16 years . Overall survival or cause-specific survival did not differ between the two groups ( median overall survival for oral chlorambucil 5.9 [ range 0 - 17.8 ] years and for observation 6.7 [ 0.5 - 18.9 ] years , p=0.84 ; median cause-specific survival 9 [ 0 - 17.8 ] years and 9.1 [ 0.67 - 18.9 ] years , respectively p=0.44 ) . In a multivariate analysis , age younger than 60 years , erythrocyte sedimentation rate ( ESR ) 20 mm/h or less , and stage III disease , conferred significant advantages in both overall survival ( p<0.0001 , 0.03 , and 0.03 , respectively ) and cause-specific survival ( p=0.002 , 0.008 , and 0.001 , respectively ) . In the observation group , at 10 years ' follow-up , 19 patients were alive and had not received chemotherapy . The actuarial chance of not needing chemotherapy ( non-lymphoma deaths censored ) at 10 years was 19 % ( 40 % if older than 70 years ) . INTERPRETATION An initial policy of watchful waiting in patients with asymptomatic , advanced stage low- grade non-Hodgkin lymphoma is appropriate , especially in patients older than age 70 years BACKGROUND Surgery is the primary treatment for patients with stage I , II , or IIIA non-small-cell lung cancer ( NSCLC ) . However , long-term survival of NSCLC patients after surgery alone is largely unsatisfactory , and the role of adjuvant chemotherapy in patient survival has not yet been established . METHODS Between January 1994 and January 1999 , 1209 patients with stage I , II , or IIIA NSCLC were r and omly assigned to receive mitomycin C ( 8 mg/m2 on day 1 ) , vindesine ( 3 mg/m2 on days 1 and 8) , and cisplatin ( 100 mg/m2 on day 1 ) every 3 weeks for three cycles ( MVP group ; n = 606 ) or no treatment ( control group ; n = 603 ) after complete resection . R and omization was stratified by investigational center , tumor size , lymph-node involvement , and the intention to perform radiotherapy . The primary endpoint was overall survival and secondary endpoints were progression-free survival and toxicity associated with adjuvant treatment . Survival curves were analyzed using the log-rank test . All statistical tests were two-sided . RESULTS After a median follow-up time of 64.5 months , there was no statistically significant difference between the two patient groups in overall survival ( hazard ratio = 0.96 , 95 % confidence interval = 0.81 to 1.13 ; P = .589 ) or progression-free survival ( hazard ratio = 0.89 , 95 % confidence interval = 0.76 to 1.03 ; P = .128 ) . Only 69 % of patients received the three planned cycles of MVP . Grade s 3 and 4 neutropenia occurred in 16 % and 12 % , respectively , of patients in the MVP arm . Radiotherapy was completed by 65 % of patients in the MVP arm and by 82 % of patients in the control group . In the multivariable analysis , only disease stage and sex were associated with survival . CONCLUSION This r and omized trial failed to prospect ively confirm a statistically significant role for adjuvant chemotherapy in completely resected NSCLC . Given the poor compliance with the MVP regimen used in this study , future studies should explore more effective treatments The data from two prospect i ve r and omised phase III trials that were initiated by the West Midl and s Ovarian Cancer Study Group ( WMOCSG ) in 1981 and 1986 , recruiting 167 and 195 patients respectively , have been pooled and the survival patterns of the 362 
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However , increased TTC may have a negative prognostic impact , and delays beyond 4 weeks should be avoided .
Timing of chemotherapy for metastatic colorectal cancer does not influence survival .
The optimal timing of chemotherapy in lung cancer is unclear ; however , rapid tumour growth and poor disease prognosis suggest that delays should be avoided wherever possible .
The optimal timing of chemotherapy in ovarian cancer is unclear as available studies are of low level , report inconsistent results and are limited to the post-surgery setting ; however , increased TTC may have a negative prognostic impact ; therefore , delays beyond 4 weeks should be avoided