cervical cancer is the second most frequently 
 diagnosed cancer among women worldwide , with nearly 80 percent arising among 
 women in developing countries . despite effective 
 screening modalities , nearly 40 percent of women in the united states present 
 with locally advanced stage 
 ii - iva cervical cancers extending beyond the cervix to invade 
 vaginal or parametrial , pelvic sidewall , bladder , or rectal tissues . in women with locally advanced cervical cancer , three 
 randomized trials have shown concurrent pelvic radiation and platinum - based 
 chemotherapy meaningfully contribute to improved disease - free survival [ 24 ] . these compelling 
 clinical results prompted the national 
 cancer institute ( nci ) to issue a publicized national clinical alert in february , 
 1999 advising concurrent 
 platinum - based chemotherapy and radiation for women with locally advanced cervical 
 cancer . according to the united states surveillance , 
 epidemiology , and end - results ( seer ) cancer registries between january , 1998 
 and december , 2002 , 35 percent of annual incident cervical cancer patients 
 arose in women aged 55 years or older ( 55 ) . however , women 55 years accounted for 55 percent of cervical cancer - related 
 mortality during this time period . widening disparity between cervical cancer 
 incidence and mortality among women 55 years questions whether chemoradiation 
 has been implemented as a national practice pattern in this patient population . population - based studies are needed to evaluate the national impact of the 1999 
 nci clinical alert advising chemoradiation for locally advanced cervical cancer . the merged seer - medicare dataset 
 offers a population - based cohort of women 55 years longitudinally tracked over the course of 
 cancer diagnosis , treatment , and follow - up . the utility of seer - medicare data to identify chemotherapy administration 
 has been validated . this study determines the frequency of chemoradiation administration in women 55 years diagnosed with cervical cancer immediately before and after 
 the 1999 nci clinical alert using the population - based seer - medicare dataset . secondary aims included identifying 
 factors in women aged 55 years 
 associated with decreased chemotherapy administration during radiation . data were abstracted from the nci - sponsored seer - medicare 
 program using the seer 11-registries plus alaska 19982003 dataset ( july , 2006 
 edition , ) . because seer data contain no 
 unique personal identifiers and thus are available for public use and research , 
 approval by an ethics committee or informed consent is not necessary to perform 
 our analyses . in general , seer data cover 
 26 percent of the us population , and therefore , are considered representative 
 of the whole us population . the seer program 
 registries routinely collect data on patient demographics ( i.e. , 
 age , race [ caucasian , african - american , asian , hispanic , or other ] , patient 
 residence , and socioeconomic status [ income per census tract ] ) , primary tumor 
 site ( i.e. , cervix ) , tumor morphology and stage at diagnosis , first course of 
 treatment , and follow - up for vital status . the seer program does not record 
 chemotherapy administration . to identify claims for chemotherapy administration , data were abstracted from three merged 
 seer - medicare files : medicare provider analysis and review ( medpar ) , carrier claims 
 ( nch ) , and outpatient claims ( outsaf ) . medpar files record all calendar year part 
 a short stay , long stay , and skilled nursing facility claims . nch files contain 
 calendar year center for medicare and medicaid 
 services ( cms ) physician / supplier part b claims . outsaf files list calendar 
 year claims for hospital outpatient departments , rural health clinics , renal 
 dialysis facilities , outpatient rehabilitation facilities , comprehensive 
 outpatient rehabilitation facilities , and community mental health centers . procedure 
 codes for chemotherapy administration made within 3 months after diagnosis of 
 cervical cancer were ascertained . the study population consisted of all female 
 patients , without previous or synchronous invasive cancers , who were diagnosed 
 with stage ii , iii , or iva cervical cancer between 1998 and 2002 ( n = 3 , 601 ) . stage 
 i patients ( n = 1 , 363 ) were excluded because they are not reliably substaged 
 ( i.e. , ib1 or ib2 ) in the seer - medicare database and the majority underwent 
 definitive surgery ( 1,044 of 1,363 [ 76.6% ] ) . women with unknown stage ( n = 357 ) , stage 
 0 ( n = 47 ) , and stage ivb 
 ( n = 402 ) cervical cancers were excluded . to ensure that chemotherapy claims 
 coincided with radiation and are not missed secondary to payment by private 
 insurance ( n = 431 ) , included women must have had medicare parts a and b coverage 
 for the duration of their cancer care ( n = 1 , 001 ) . for determination of chemoradiation administration , included 
 women 55 years must have undergone radiation ( external pelvic and brachytherapy 
 implant ) for primary treatment of their cervical cancer ( n = 385 ) . the charlson comorbidity index is a summary 
 measure of 19 comorbid conditions , each assigned a weighting factor according 
 to its potential for influencing mortality . charlson comorbidity indices   were calculated by abstracting medicare icd-9-cm diagnosis 
 and procedure codes relating to cardiovascular , cerebrovascular , hepatic , 
 renal , diabetic , connective tissue , or neoplastic disease among inpatient and 
 outpatient claims made for each woman one year prior to the diagnosis of 
 cervical cancer [ 1214 ] . women diagnosed with chronic end - stage renal disease or 
 listed in the seer - medicare dataset as having diagnosis codes for renal 
 disease , renal failure , or renal insufficiency were considered women as having renal 
 disease comorbidity . for this analysis , the day of diagnosis in seer was 
 arbitrarily assigned as the 15th of the month . women were considered to have 
 received concurrent chemoradiation therapy if there was at least one submitted 
 billing claim for chemotherapy within a three - month period after diagnosis and 
 radiation treatment . chi - square tests for categorical variables and student 's t - tests for continuous variables were 
 used to compare differences in demographic and tumor variables by chemoradiation 
 administration . adjusted odds ratios for chemoradiation were generated using multivariate 
 logistic regression models sequentially controlling age , race , residence , 
 socioeconomic status , comorbidity , tumor stage , and histology as defined in 
 table 1 . a p - value  < 0.05 
 ( two - sided ) was used to determine statistical significance . computer programing 
 and statistical analyses were performed using sas software version 9.1 ( sas 
 institute , cary , nc ) . after exclusions , 385 women aged 55 years 
 underwent pelvic radiation and intracavitary brachytherapy for primary 
 treatment of cervical cancer between january , 1998 and december , 2002 . table 1 presents patient demographic and tumor 
 variables for the 385 women included in this analysis . the majority of cases 
 were stage ii squamous cell cancers diagnosed in caucasian women who had minimal comorbidities 
 and who resided in large metropolitan areas . among women aged 55 years identified in the seer - medicare dataset , 166 of 385 
 ( 43% ) received chemoradiation . cisplatin chemotherapy was specifically claimed 
 in 129 of 166 ( 78% ) women . before the 1999 nci clinical alert , 30 percent of 
 women aged 55 years ( 29 of 97 women ) identified in the seer - medicare registry received at least one 
 chemotherapy dose during radiation ( see table 2 ) . in the year 2000 and after 
 the 1999 nci clinical alert , the proportion receiving chemoradiation was 41 
 percent of women aged 55 years ( 36 of 87 women ) . afterwards , the 
 proportion receiving chemoradiation was greater than 50 percent ( see table 2 ) . 
 between 1998 and 2002 , a significant increasing trend for chemoradiation administration 
 was observed among women aged 55 years registered in the seer - medicare dataset ( p < .01 ) . the 
 median number of chemotherapy claims during radiation was four ( mean 4.2 , 
 standard deviation 1.9 , table 2 ) . among women treated with chemoradiation , 78 
 of 166 ( 47% ) received five or more cycles of chemotherapy . table 3 compares variables 
 in univariate analyses evaluating patients who received concurrent chemotherapy 
 and radiation compared to those who received radiation alone . the mean age of 
 women receiving chemoradiation was significantly younger ( table 3 , p < .001 ) . the proportion of women residing 
 in urban , less urban , and rural areas receiving chemoradiation was 
 significantly higher than receiving radiation alone ( 20% versus 10% , p = .03 ) . chemotherapy 
 use during radiation was not associated with race , socioeconomic 
 status , tumor histology or stage , or comorbidity index . the proportion of women 
 diagnosed with renal disease comorbidity was similar among chemoradiation ( 18/166 , 11% ) 
 and radiation alone ( 21/219 , 10% ) treatment groups ( p = .73 ) . table 4 presents multivariate analyses for odds 
 of receiving concurrent chemoradiation adjusting for patient demographic and tumor 
 differences . women aged 71 years or older had a significantly decreased odds of 
 undergoing chemoradiation treatment as compared to women aged 55 to 70 years ( p = .04 ) . 
 for women 71 years or older , the proportion of women with renal disease who 
 received chemoradiation ( 9 of 95 , 10% ) and radiation alone ( 7 of 138 , 5% ) was 
 similar ( p = .19 ) . in multivariate analyses , women residing 
 in urban , less urban , and rural areas had significantly increased odds of 
 undergoing chemoradiation treatment as compared to women residing in 
 metropolitan areas ( p < .001 ) . the 
 proportion of women 71 years or older in big metropolitan , metropolitan , and 
 urban / less urban / rural areas was 42 percent ( 99 of 235 ) , 35 percent ( 33 of 61 ) , 
 and 36 percent ( 20 of 56 ) , respectively ( p = .41 ) . race , 
 socioeconomic status , comorbidity index , and tumor histology or stage were not 
 significant confounders for chemoradiation treatment . the present data from the us population - based seer - medicare database indicate that the 1999 nci clinical 
 alert for platinum - based chemoradiation has had an impact on chemoradiation use 
 for locally advanced stage 
 ii - iva cervical cancers diagnosed in women 55 years . eighteen 
 months before the nci clinical alert , less than 30 percent of women 55 
 years received chemoradiation . 
 however , within 18 months of the nci clinical alert , the proportion of women 55 
 years with locally advanced cervical cancer receiving chemoradiation 
 significantly rose to 50 percent . since chemoradiation use has steadily risen 
 through the last seer - medicare cohort available for study ( i.e. , 2002 ) , the 
 recommendation has been followed but a substantial fraction of women 55 years 
 still did not receive concurrent chemoradiation in 2002 three years after the 
 nci clinical alert . age is a risk factor for pelvic and distant relapse as 
 well as death after treatment for cervical cancer . in multivariate analyses 
 conducted by the gynecologic oncology group evaluating radiation and chemotherapeutic 
 radiation sensitizers , these findings led to the 
 controversial suggestion that younger patient age at diagnosis was associated 
 with high mortality ; and yet , the inferior mortality outcomes attributable to 
 younger patient age have vanished in the era of platinum - based chemoradiation 
 as no contemporary gynecologic oncology group or cooperative group study 
 identifies age as a significant confounder upon survival outcomes [ 24 ] . while platinum - based chemoradiation appears to have 
 decreased mortality in younger women , it remains unknown whether older women 
 are deriving full survival benefit from chemoradiation treatment . perceived and 
 actual hematological , renal , gastrointestinal , and neural toxicities of platinum 
 chemotherapy perhaps influence physicians to not consider coadministration of 
 chemotherapy during radiation in older women . these data indicate that 
 significantly fewer women older than 71 years who have locally advanced 
 cervical cancer receive chemoradiation  even though the 
 survival of these older patients who receive chemoradiation approaches that of 
 younger patients who undergo chemoradiation treatment [ 24 , 16 ] . this study is not the first to 
 identify this age trend . in a pattern of care study , it was reported that 63 percent 
 of all women captured in this survey underwent concurrent chemotherapy and radiation in 1999 , as 
 compared to 26 percent in 1998 . twenty - five percent of women 60 years or older 
 received chemoradiation as compared to 48 percent among women aged 40 years or 
 less ( p = .02 ) . in an earlier analysis of the seer - medicare database 
 controlling for racial and socioeconomic factors , increasing age was strongly 
 associated ( p < .0001 ) with 
 receiving neither chemoradiation nor radiation treatment for cervical cancer . however , both studies capture only those women treated 
 through 1999 , study periods ending when the 1999 nci clinical alert were released . thus , a true assessment of the 
 impact of the nci clinical alert is essentially unknown . the present data are the 
 first assessment of chemoradiation treatment after the 1999 nci clinical alert for 
 chemoradiation treatment of locally advanced cervical cancer in women aged 55 years . the us seer - medicare dataset is an nci - sponsored cancer registry that reflects 
 a wide range of race / ethnic , demographic , and socioeconomic diversity and that 
 avails itself to cancer health service delivery analyses in women aged 55 
 years . the data presented herein reflect 
 prospectively collected but not randomized practice and usage of 
 chemoradiation . these data measure the impact of randomized clinical trials in 
 cervical cancer , as popularized by the national 1999 nci clinical alert , on 
 clinical chemoradiation practices for the treatment of cervical cancer . thus , these 
 data conveniently sample a small proportion of the total number of women with 
 locally advanced cervical cancer treated in the us 
  each year . consequently , analyses 
 on these nonrandomly treated women can only be considered as an interpretive 
 guide for changing trends in chemoradiation usage for locally advanced cervical 
 cancer . indeed , the present data suggest that women 55 years with locally advanced cervical cancer are 
 increasingly likely to receive chemoradiation . data also suggest that 
 chemoradiation use has significantly lagged behind in women 71 years or 
 older compared to women 55 to 70 years . perhaps physicians applied the nci recommendations to 
 some groups of women more consistently than others . in this study of the 
 seer - medicare population while the nci clinical alert has 
 strongly endorsed use of chemoradiation for all patients with locally advanced 
 cervical cancer , it is worth considering the causes of disparity in 
 chemoradiation use among younger and older women . the exact regimen of 
 chemotherapy administration , patient - specific chemotherapy dosage , and adverse 
 effects of treatment can not be abstracted reliably from the seer - medicare 
 database . while reluctance of older patients to receive chemotherapy due to 
 perceived toxicities , tolerability , or an apathetic attitude often are 
 difficult to enumerate , physical limitations such as comorbid disease may be 
 more reliably estimated in a population - based database that records these 
 factors . in the current study , comorbid renal 
 disease , as identified by diagnosis codes for renal disease , renal failure , or 
 renal insufficiency , also was not associated with infrequent chemoradiation 
 treatment . demographic variables of 
 race , socioeconomic status , and tumor variables of histology and clinical stage 
 were not associated with more infrequent chemoradiation treatment , a reassuring 
 finding of this study . however , a significant disparity in the proportion of 
 women 55 years in metropolitan and nonmetropolitan residencies was observed 
 in this study . only 40 percent of the women residing in metropolitan areas as 
 compared to 60 percent of women residing in urban , less urban , and rural residencies 
 received chemoradiation during the entire 1998 to 2002 period under study ( p = .03 ) . disparity in age cohorts among 
 residences does not account for this difference as the proportion of women aged 
 71 years or older among big metropolitan , metropolitan , and urban / less 
 urban / rural areas is similar ( p = .41 ) . the issues surrounding the more frequent use of radiation alone in metropolitan 
 residencies are difficult to abstract but perhaps are related to unreported 
 comorbid disease , patient refusal , and perceived toxicities / tolerability of the 
 combined treatment regimen . the data can not exclude the possibility that 
 healthcare - system - related factors , such as access to care or differences in 
 referrals for chemotherapy consultation , could explain the findings of the 
 current study . the reasons why older women do not receive chemotherapy remain 
 elusive , and perhaps , future population - based studies may provide more 
 meaningful insight . the population 
 covered by seer program representing 26 percent of the general population compares 
 favorably to us census population data with regard to measures of poverty and 
 education , but has a higher 
 proportion of urban and foreign - born persons in the registry as compared 
 to the general us population . census population estimates for the year 2000   suggest that 73 percent of women aged 55 years live in metropolitan areas as compared to 
 85 percent registered in the seer - medicare dataset . there may also be 
 differences in the underlying racial distribution of the seer - medicare dataset 
 compared to the us population comprising new incident cases of cervical cancer . this 
 seer - medicare dataset used to analyze the impact of the nci clinical alert is limited to women aged 55 years that must have been enrolled in medicare 
 part a and b coverage for the duration of their cervical cancer treatment . thus , 
 by limiting the dataset by an age criterion of 55 years , this analysis does not capture 
 chemoradiation treatment in young women who comprise the majority of new incident cases in 
 the us . moreover , identification of chemoradiation in the seer - medicare population 
 follows the centers for medicare and medicaid services ' coverage policies 
 relating to chemotherapy administration . current centers for medicare and 
 medicaid services policy permits fee - for - service reimbursement for intravenous 
 chemotherapy , including cisplatin chemotherapy administration . as 
 medicare billing claims for chemotherapy administration are often coded within 
 six months of initial cancer diagnosis , this analysis ' three - month 
 timeframe for coincident chemotherapy and radiation treatment in the 
 seer - medicare dataset is reasonable . women simultaneously enrolled by a private 
 insurer were excluded as chemotherapy administration may have been paid by this 
 entity rather than medicare , and thus falsely skewing results toward treatment 
 with radiation alone . another limitation is that comorbid disease documentation 
 in a population - based dataset is derived from claims - based administrative coding , 
 which may generally be less complete than data obtained from direct medical 
 chart review . interpretative criticism also concerns the timeliness of the 
 seer - medicare cohort under study , as these patients may be poorly reflective of 
 modern chemoradiation practice ; and yet , seer data and medicare data are 
 infrequently merged . as such , the 19982002 seer - medicare 
 patient population represents the most contemporary cohort in which to study 
 concurrent seer radiation and medicare chemotherapy recorded administration . the current analysis of 19982002 seer - medicare 
 data indicates increased utilization of chemoradiation treatment since the 1999 
 nci clinical alert strongly 
 advocating for concurrent chemotherapy and radiation for locally advanced 
 cervical cancer . , the population - based seer - medicare registry identifies 43 
 percent of the women 55 years with locally advanced cervical 
 cancer receiving chemoradiation despite published guidelines to the contrary . while 
 our study is provocative , it is unable to definitively assess current national 
 chemoradiation practice patterns . to further corroborate our findings , it would 
 be interesting to analyze nci - sponsored 
 clinical trials enrolling women aged 55 years to determine if the number of chemotherapy cycles 
 given during radiation impacts clinical outcome . further analysis of national 
 practice patterns from future us surveillance , epidemiology , and end - results - medicare 
 mergers is warranted to identify contributing factors leading to the disparity 
 in incidence and mortality among women 55 years with locally advanced cervical 
 cancer .
our study evaluated whether 1999 national cancer institute ( nci ) chemoradiation guidelines for cervical cancer impacted treatment of women 55 years . 
 we identified 385 women 55 years ( median , 72 years ) diagnosed with stage ii - iva cervical cancer between january , 1998 and december , 2002 in the united states surveillance , epidemiology , and end results ( seer)-medicare registries . 
 chemoradiation frequency tables were constructed for age , race , community setting , socioeconomic status , and comorbidity index . 
 of 385 women , 166 ( 43% ) received chemoradiation as primary treatment . 
 prior to the 1999 nci clinical alert , 5/43 ( 12% ) in 1998 and 24/54 ( 44% ) in 1999 received chemoradiation . 
 the chemoradiation proportion was 41% ( 36/87 ) in 2000 , 48% ( 51/107 ) in 2001 , and 53% ( 50/94 ) in 2002 ( trend , p < .01 ) . 
 women 71 years had significantly lower odds of chemoradiation ( p = .04 ) . while seer - medicare data indicated an increasing trend for chemoradiation after the 1999 nci clinical alert , chemoradiation was less frequent in elderly women with cervical cancer .