Patterns of enrollment on cooperative group studies. An analysis of trends from the Los Angeles County Cancer Surveillance Program

Challenges and limitations of clinical trials in the adolescent and young adult CNS cancer population: A systematic review

Background

The adolescent and young adult (AYA) cancer population, aged 15-39, carries significant morbidity and mortality. Despite growing recognition of unique challenges with this age group, there has been little documentation of unmet needs in their care, trial participation, and quality of life, particularly in those with primary brain tumors.

Methods

A systematic literature review of 4 databases was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. Studies included editorials, reviews, and practice guidelines on the challenges and limitations faced by the AYA population. Papers had to address CNS tumors.

Results

Sixty-eight studies met the inclusion criteria. The challenges and limitations in clinical trials in the AYA population were synthesized into 11 categories: molecular heterogeneity, tumor biology, diagnostic delay, access to care, physician factors, patient factors, primary brain tumor (PBT) factors, accrual, limited trials, long term follow up, and trial design. The published papers' recommendations were categorized based on the target of the recommendation: providers, coordination of care, organizations, accrual, and trial design. The AYA cancer population was found to suffer from unique challenges and barriers to care and the construction of trials.

Conclusions

The AYA CNS cancer population suffers from unique challenges and barriers to care and construction of trials that make it critical to acknowledge AYAs as a distinct patient population. In addition, AYAs with primary brain tumors are underrecognized and underreported in current literature. More studies in the AYA primary brain tumor patient population are needed to improve their care and participation in trials.

Disparities in pediatric acute myeloid leukemia (AML) clinical trial enrollment

Equal access to clinical trial enrollment is important to ensure that findings are generalizable to the broader population. This study aimed to evaluate disparities in enrollment on pediatric oncology clinical trials. We assessed the relationship between patient characteristics and enrollment on COG trial AAML1031 in a cohort of pediatric patients with AML in the Pediatric Health Information System. The associations of enrollment with outcomes were evaluated. Non-Hispanic Black patients, infants, and patients from zip codes with a lower proportion of poverty were less likely to enroll (30% vs. 61%, p = .004; 34% vs. 58%, p = .003; 46% vs. 58%, p = .02). On-therapy mortality was similar among enrolled and nonenrolled patients (7.3% vs. 8.9%, p = .47). Differences in early mortality were more pronounced among nonenrolled patients compared to enrolled patients (3.0% vs. 0.5%, p = .03). Understanding the etiology of these disparities will inform strategies to ensure balanced access to clinical trials across patient populations.

A prospective comparison of cancer clinical trial availability and enrollment among adolescents/young adults treated at an adult cancer hospital or affiliated children's hospital

BACKGROUND

Low cancer clinical trial (CCT) enrollment may contribute to survival disparities affecting adolescents and young adults (AYAs) (ages 15-39 years). The objective of this study was to evaluate whether differences in CCT availability related to treatment site could explain the low CCT enrollment.

METHODS

This prospective, observational cohort study was conducted at an academic children's hospital and its affiliated but geographically separated adult cancer hospital within a National Cancer Institute-designated Comprehensive Cancer Center. For consecutive, newly diagnosed AYA patients, it was determined whether an appropriate CCT existed nationally, was available at the treatment site, and was used for enrollment. Proportions of AYAs in these categories were compared between sites using the chi-square test.

RESULTS

One hundred fifty-two consecutive AYA patients were included from the children's hospital (n = 68; ages 15-20 years) and the adult cancer hospital (n = 84; ages 18-39 years). Although there was no difference in CCT existence for individual AYA patients by site (children's hospital [36 of 68 patients; 52.9%] vs adult cancer hospital [45 of 84 patients; 53.6%]; P = .938), CCT availability was significantly lower at the adult cancer hospital (14 of 84 patients [16.7%] vs 30 of 68 [44.1%] at the children's hospital; P < .001). The proportion of AYAs enrolled was low at both sites (8 of 68 patients [11.8%] vs 6 of 84 patients [7.1%], respectively; P = .327). Fewer existing CCTs were available at the adult cancer hospital (4 of 27 patients [14.8%] vs 8 of 14 patients [57.1%], respectively), and those were directed toward solid tumors and new agents.

CONCLUSIONS

Efforts to improve low CCT enrollment among AYAs should be differentiated by treatment site. In the adult setting, these efforts should be aimed at improving CCT availability by overcoming site-level barriers to opening existing CCTs.

A prospective, observational cohort study comparing cancer clinical trial availability and enrollment between early adolescents/young adults and children

BACKGROUND

Poor enrollment of adolescents and young adults (AYAs) (ages 15-39 years) onto cancer clinical trials (CCTs) may contribute to inferior survival gains compared with children. In this study, the authors assessed whether differences in CCT availability would explain lower CCT enrollment for early AYAs (eAYAs) (ages 15-21 years).

METHODS

This prospective, observational cohort study was conducted at a single academic children's hospital. For consecutive patients who were newly diagnosed with cancer over a 13-month period, it was determined whether an appropriate CCT existed nationally or was available locally and whether enrollment on that CCT occurred. The proportions of eAYAs versus children in each category were compared using the chi-square test. The impact of age and other factors on enrollment status was assessed using logistic regression analysis.

RESULTS

Among 216 patients, 58 were eAYAs, and 158 were children. There was no difference in the proportion of eAYAs versus children who had an existing CCT (28 of 58 eAYAs [48.3%] vs 85 of 158 children [53.8%]; P = .47) or an available CCT (23 of 58 eAYAs [39.7%] vs 75 of 158 children [47.5%]; P = .31). However, significantly fewer eAYAs were enrolled when a CCT was available (7 of 23 eAYAs [30.4%] vs 50 of 75 children [67.7%]; P = .002). In multivariable analysis, eAYAs were significantly less likely than children to be enrolled in an available CCT (adjusted odds ratio, 0.22; 95% confidence interval, 0.08-0.62).

CONCLUSIONS

Equal proportions of children and eAYAs had CCTs available, but significantly fewer eAYAs were enrolled. These findings suggest that, for eAYAs, factors other than CCT availability are important enrollment barriers and should be addressed. Cancer 2018;124:983-90. © 2017 American Cancer Society.

Are survival and mortality rates associated with recruitment to clinical trials in teenage and young adult patients with acute lymphoblastic leukaemia? A retrospective observational analysis in England

OBJECTIVE

Participation rates in clinical trials are low in teenagers and young adults (TYA) with cancer. Whilst the importance of clinical trials in informing best practice is well established, data regarding individual patient benefit are scarce. We have investigated the association between overall survival and trial recruitment in TYA patients with acute lymphoblastic leukaemia (ALL).

DESIGN

Retrospective.

SETTING

National (England) TYA patients treated for ALL.

PARTICIPANTS

511 patients aged 15-24 years diagnosed with ALL between 2004 and 2010 inclusive, of whom 239 (46.7%) participated in the UKALL2003 trial.

OUTCOME MEASURES

Patients were identified using National Clinical Trial (UKALL2003) and Cancer Registry (National Cancer Data Repository, English National Cancer Online Registration Environment) Databases. Relative survival rates were calculated for trial and non-trial patients and observed differences were modelled using a multiple regression approach. The numbers and percentages of deaths in those patients included in the survival analysis were determined for each 3-month period, p values were calculated using the two-tailed z-test for difference between proportions and 95% CIs for percentage deaths were derived using the binomial distribution based on the Wilson Score method.

RESULTS

Patients treated on the trial had a 17.9% better 2-year survival (85.4% vs 67.5%, p<0.001) and 8.9% better 1-year survival (90.8% vs 81.9%, p=0.004) than those not on the trial. 35 (14.6%) patients recruited to the trial died in the 2 years following diagnosis compared with 86 (32.6%) of those not recruited (p<0.001).

CONCLUSIONS

TYA patients recruited to the clinical trial UKALL 2003 in England had a lower risk of mortality and a higher overall survival than contemporaneous non-trial patients. These data underline the potential for individual patient benefit in participating in a clinical trial and the importance of international efforts to increase trial participation in the TYA age group.

TRIAL REGISTRATION NUMBER

ISRCTN07355119.

Most children with cancer are not enrolled on a clinical trial in Canada: a population-based study

Background

Primary objective was to describe the proportion of children newly diagnosed with cancer enrolled on a therapeutic clinical trial. Secondary objectives were to describe reasons for non-enrollment and factors associated with enrollment on trials.

Methods

In this retrospective cohort study, we included children newly diagnosed with cancer between 0 and 14 years of age and diagnosed from 2001 to 2012. We used data from the Cancer in Young People in Canada (CYP-C) national pediatric cancer population-based database. CYP-C captures all cases of pediatric cancer (0–14 years) diagnosed and treated at one of the 17 tertiary pediatric oncology centers in Canada. Non-enrollment was evaluated using univariate and multiple logistic regression analysis.

Results

There were 9204 children with cancer included, of whom 2533 (27.5%) were enrolled on a clinical trial. The most common reasons cited for non-enrollment were lack of an available trial (52.2%) and physician choice (11.2%). In multiple regression, Asian and Arab/west Asian race were associated with lower enrollment (P = 0.006 and P = 0.032 respectively). All cancer diagnoses were more likely to be enrolled compared to astrocytoma and children with acute lymphoblastic leukemia had an almost 18-fold increased odds of enrollment compared to astrocytoma (P < 0.0001). Greater distance from the tertiary care center was independently associated with non-enrollment (P < 0.0001).

Conclusions

In Canada, 27.5% of children with cancer are enrolled onto therapeutic clinical trials and lack of an available trial is the most common reason contributing to non-enrollment. Future research should better understand reasons for lack of trial availability and physician preferences to not offer trials.

Case-linked analysis of clinical trial enrollment among adolescents and young adults at a National Cancer Institute-designated comprehensive cancer center

BACKGROUND

Poor accrual to cancer clinical trials may contribute to the lower improvement in survival observed for adolescents and young adults (AYAs) (those aged 15-39 years) with cancer. This has been difficult to quantify without reliable mechanisms to link incident cases with study enrollments. Using unique resources available at their National Cancer Institute-designated comprehensive cancer center, the authors compared the percentage of AYAs, children, and older adults enrolled onto cancer clinical trials and determined predictors of enrollment.

METHODS

Patients diagnosed with cancer from January 2008 through December 2012 at 1 pediatric and 2 adult University of Southern California hospitals were identified through the California Cancer Registry and individually linked to institutional trial enrollment databases. The availability of clinical trials was assessed.

RESULTS

Across the center, the enrollment percentage for AYAs (6%) was equal to that of older adults (6%), but was less than that for children (22%) (P < .01). Within the children's hospital, the AYA enrollment percentage was also less than that for children (15% vs 23%, respectively; P<.01). On multivariate analysis, diagnosis and site of care were found to be predictive of AYA enrollment onto therapeutic and nontherapeutic studies. Hispanic and Asian/Pacific Islander individuals were more likely to enroll onto nontherapeutic studies compared with non-Hispanic whites, but no racial/ethnic difference was observed for therapeutic studies.

CONCLUSIONS

In the current study, the percentages of AYAs and older adults enrolled onto therapeutic trials were low but similar. Diagnosis, site of care, and race/ethnicity appear to be predictive of enrollment. Prospective mechanisms must be instituted to capture reasons for nonenrollment of AYAs and develop corrective interventions.

The Clinical Trials Gap for Adolescents and Young Adults with Cancer: Recent Progress and Conceptual Framework for Continued Research

Over the past 30 years, adolescents and young adults (AYA, 15-39 years of age) with cancer have shown significantly less improvement in survival than younger and older patients. Because evidence suggests this may be related to their low participation in cancer clinical trials, increasing accrual to these trials has become a priority for closing this "AYA gap." This paper reviews data documenting low AYA enrollment, presents a conceptual framework for research and intervention (Clinical Trials Pathway to Enrollment) and summarizes recent developments in the United States National Cancer Institute-sponsored clinical trials enterprise that are expected to improve AYA enrollment, including the National Clinical Trials Network (NCTN) and expanded scientific collaboration between the Children's Oncology Group and adult NCTN groups. While time will be required for the effects of these changes to be fully realized, they offer a mechanism for facilitating the breadth of clinical/translational research needed for advancing AYA oncology and measuring its impact.

Clinical trial enrollment among adolescents with cancer: supplement overview

BACKGROUND

Survival rates for children with cancer have significantly increased over the past 35 years. However, adolescents with cancer aged 15 to 19 years have had less progress in survival prolongation compared with younger children, which may be due to lower clinical trial enrollment among adolescents with cancer. To help address this issue, the Centers for Disease Control and Prevention (CDC) convened a series of webinars to identify salient issues and measures to address this problem. This supplement is intended to raise awareness about the unique challenges of clinical trial enrollment among adolescents with cancer.

METHODS

The CDC convened a workgroup of researchers and health care providers in the field of adolescent and young adult oncology and cancer survivorship to examine the barriers and challenges limiting the participation of adolescents in clinical trials and to define ways to improve on these concerns.

RESULTS

The workgroup identified 3 distinct issues affecting clinical trial enrollment among adolescents with cancer: (1) many adolescents with cancer are not referred to institutions where clinical trials are offered, (2) there are limited numbers of clinical trials for adolescents with cancer, and (3) psychosocial barriers impede adolescents with cancer from enrolling in clinical trials.

CONCLUSIONS

Adolescents with cancer have the smallest proportion and least number of patients enrolled in clinical trials in pediatric oncology. Successfully addressing this challenge requires improving referral to existing clinical trials, addressing regulatory barriers to clinical trial enrollment, increasing the number of clinical trials for adolescents, and addressing unique psychosocial barriers to clinical trial enrollment.

Treatment setting, clinical trial enrollment, and subsequent outcomes among adolescents with cancer: a literature review

BACKGROUND

There has been an overall improvement in survival rates for persons with cancer over the past 35 years. However, these gains are less prevalent among adolescents with cancer aged 15 to 19 years, which may be due to lower clinical trial enrollment among adolescents with cancer.

METHODS

We conducted a literature review to assess current research regarding clinical trial enrollment and subsequent outcomes among adolescents with cancer. The search included English-language publications that reported original data from January 1985 to October 2011.

RESULTS

The search identified 539 records. Of these 539 records, there were 30 relevant original research articles. Multiple studies reported that adolescents with cancer are enrolled in clinical trials at lower rates compared with younger children and older adults. Treatment setting, physician type, and institution type may all be factors in the low enrollment rate among adolescents. Few data focused solely on adolescents, with many studies combining adolescents with young adults. The number of available studies related to this topic was limited, with significant variability in study design, methods, and outcomes.

CONCLUSIONS

This literature review suggests that adolescents with cancer are not treated at optimal settings and are enrolled in clinical trials at low rates. This may lead to inferior treatment and poor subsequent medical and psychosocial outcomes. The scarcity in data further validates the need for additional research focusing on this population.

Understanding and addressing the lack of clinical trial enrollment among adolescents with cancer

Despite overall improvement in survival, morbidity, and quality of life of US patients with cancer, this progress is less prevalent in the population of adolescent and young adult patients with cancer, including those between the ages of 15 and 19 years. Evidence suggests that participation in clinical trials is associated with better survival outcomes among children and adolescents with cancer; however, adolescents have lower clinical trial participation rates compared with younger age cohorts. To better understand the unique concerns among adolescent patients with cancer, the Division of Cancer Prevention and Control at the Centers for Disease Control and Prevention convened a workgroup of researchers and health care providers in the field of adolescent and young adult oncology and cancer survivorship to examine the barriers and challenges limiting the participation of adolescents in clinical trials and to define ways to improve upon these concerns. This article summarizes the activities of the workgroup and their suggestions for enhanced accrual.

Adolescents and young adults with cancer: An orphaned population

Adolescents and young adults (AYAs [15 to 29 years of age]) with cancer have a distinct cancer epidemiology, evolving hormonal milieu, maturing development, transitions in autonomy, increasing demands in education, entry into the workplace and family responsibilities. The prevalence of epithelial cancers in AYA patients represents a major shift from the embryonal cancers that predominate in early childhood. Thus, one would expect a specialized expertise to be required in caring for these patients, who typically fall between paediatric and oncology spheres of practice. Complex issues contribute to the lower survival rates noted for AYAs compared with those of younger patients, even with the same cancer. Cooperative group clinical trial participation has been crucial in advancing the excellent outcomes accomplished in paediatric oncology, yet participation by adolescents in clinical trials (either adult or paediatric) is typically low. There is increasing evidence that both appropriate location of care and access to specialists in paediatric or adult oncology contribute to favourable outcomes. Issues specific to AYA patients should be studied rigorously so that evidence-based approaches may be used to reduce waiting times, ensure prompt referral to appropriate centres, increase accrual to clinical trials, foster compliance, provide comprehensive supportive care and promote programs designed to enhance survivorship.

Patterns of enrollment of infants with central nervous system tumours on cooperative group studies: a report from the Canadian Pediatric Brain Tumour Consortium

In children under the age of 3, the most common solid tumours are brain tumors. Treatment for many of these patients includes surgery, chemotherapy and rarely radiation therapy. Many clinical trials have been performed in an attempt to establish the best treatment for these patients. Patients enrolled on clinical trials contribute to the establishment of the best therapy. We performed a national survey of all children less than the age of three with brain tumours and examined the contribution these patients made to clinical trials. A data bank was established using data collected from Canadian pediatric oncology centers on children less than age 3 diagnosed with brain tumours between 1990 and 2005. Data were collected on the use of adjunctive treatment after surgery, treatment on a protocol, reasons patients were not registered on a protocol, and reasons for discontinuation of therapy. From the 579 cases in the data bank, 302 (52%) patients were treated with further therapy after surgery. The use of further therapy after surgery was significantly higher in patients with cerebellar and brain stem tumors, patients who were over 1 year of age, patients with ependymal and embryonal tumors, and patients with high grade malignant tumors. Only 62 (21%) patients were enrolled on a protocol for therapy. No factor was significant for being enrolled on a protocol. Reasons for not being registered on a protocol were mainly that there was no open COG/POG/CCG study or the study was not open at the institution. The therapy was stopped because of completion of the protocol in 50% and because of disease progression in 34%. In Canada, about half of children under the age of 36 months with brain tumors are undergoing therapy following surgery for their malignancy but only a small fraction of them are enrolled on a clinical trial. There needs to be improved availability of clinical trials for these patients so that novel therapies can be evaluated and survival improved.

Testing three different cancer genetics registry recruitment methods with Hispanic cancer patients and their family members previously registered in local cancer registries in Texas

OBJECTIVE

To increase accrual among Hispanics to the Cancer Genetics Network national cancer genetics registry.

METHODS

Drawing from South Texas cancer registries, 444 Hispanic men and women were randomly assigned to one of three experimental conditions: standard direct-mailed procedures (X1), X1 plus culturally tailored materials (X2), and X2 plus interpersonal phone contact (X3). Participants were also surveyed about the effectiveness of the education materials and the phone contact. A refusal survey was provided for those who declined to join the study.

RESULTS

A total of 154 individuals joined the Cancer Genetics Network. The X3 condition yielded the greatest accrual (43.2%) compared to X1 (30.9%) and X2 (29.9%; p < 0.05). Tailored materials appeared to have no effect but were highly regarded. The main reasons for not participating were a lack of interest and time requirements.

CONCLUSION

Interpersonal communication can have a powerful effect on recruitment. However, more research is needed to determine the cost-efficacy of more labor-intensive approaches to registry accrual.

Barriers to recruiting underrepresented populations to cancer clinical trials: a systematic review

Racial and ethnic minorities, older adults, rural residents, and individuals of low socioeconomic status are underrepresented among participants in cancer-related trials. The authors conducted a systematic review to determine the barriers to participation of underrepresented populations in cancer-related trials. Their search included English-language publications that reported original data on the recruitment of underrepresented groups to cancer treatment or prevention trials between 1966 and December 2005 in multiple electronic databases. They also hand-searched titles in 34 journals from January 2003 to December 2005 and they examined reference lists for eligible articles. Titles and abstracts were reviewed to identify relevant studies. Data on barriers to participation were synthesized both qualitatively and based on statistically significant associations with trial enrollment. Of 5257 studies that were cited, 65 studies were eligible for inclusion in the current analysis, including 46 studies on recruitment into cancer therapeutic trials, 15 studies on recruitment into prevention trials, and 4 studies on recruitment into both prevention and treatment trials. Numerous factors were reported as barriers to participation in cancer-related trials. However, only 20 of the studies reported statistically significant associations between hypothesized barriers and enrollment. The available evidence had limitations in quality regarding representativeness, justification of study methods, the reliability and validity of data-collection methods, potential for bias, and data analysis. The results indicated that underrepresented populations face numerous barriers to participation in cancer-related trials. The current systematic review highlighting the literature on recruitment of underrepresented populations to cancer trials and may be used as the evidence base toward developing an agenda for etiologic and intervention research to reduce the disparities in participation in cancer-related trials.

Defining "success" in recruitment of underrepresented populations to cancer clinical trials: moving toward a more consistent approach

Although medically underserved groups bear a heavy burden of cancer disease and governmental agencies have required inclusion of minorities and women in cancer clinical trials since 1993, many of these groups are underrepresented in cancer prevention or treatment clinical trials. To assess and enhance recruitment of underrepresented populations into cancer-related clinical trials, investigators and governmental agencies need consistent measurement approaches for recruitment that can be applied to diverse settings where trials are conducted. We conducted a systematic review to evaluate what measurement approaches were used to evaluate the success of recruitment of underrepresented groups into cancer prevention or treatment trials, and whether these recruitment goals were stated a priori. Only two articles reported an a priori recruitment goal. The recruitment measurement approaches varied considerably, with no consistent standard, especially for individual trials. By using the empiric evidence from this review in conjunction with the National Institutes of Health (NIH) guidelines, we constructed a framework for choosing consistent a priori recruitment goals for underrepresented groups based on the research question and study location. Using consistent measurement approaches for underrepresented groups will improve comparability of recruitment strategies across trials, improve equity in distribution of benefits and burdens of cancer-related clinical trials, and may improve applicability of trial results to multiple populations.

Clinical trial accrual among new cancer patients at a community-based cancer center

BACKGROUND

To the authors' knowledge, only limited data are available regarding clinical trial accrual patterns and the barriers encountered among newly diagnosed patients seen at community-based cancer centers.

METHODS

In the current study, the authors prospectively collected clinical and sociodemographic data from all adult patients seen at a community-based cancer center who had new cancers diagnosed between 2003-2004. Clinical trial enrollment decisions were noted and factors that prevented accrual were identified.

RESULTS

There was a total of 1012 new cancer patients. In 587 patients (58%), clinical trials appropriate for the diagnosis and stage of disease were not available. Among those patients for whom trials were available, 19.8% did not meet eligibility criteria, and only 9.9% of patients were enrolled. Although more trials were found to be available for women compared with men (51% vs. 32%; P < 0.01), the accrual rates were equal (11.2% vs. 7.6%; P = 0.24). Elderly patients comprised approximately 59.4% of those patients with available trials, but they were less likely to be enrolled (5.1% vs. 16.8%; P < 0.01). The major barriers to nonparticipation can be grouped into protocol limitations (68.1%), physician triage (16%), and patient decisions (15.9%). The overall accrual rate when all patients were included was 4% (42 of 1012 patients).

CONCLUSIONS

At the study institution, participation in clinical trials is reported to be low. The unavailability of appropriate clinical trials represents the most significant barrier. Continuing efforts to encourage physicians and to educate patients remain necessary. If the current study findings are found to be applicable to other community-based cancer centers, making a larger variety of clinical trials available to the community may help to improve the accrual of patients to national cancer clinical trials.

Long-term survival probabilities for childhood rhabdomyosarcoma. A population-based evaluation

BACKGROUND

Evidence from clinical trials has documented improvements in event-free survival from childhood rhabdomyosarcoma (RMS) since the 1970s; however, the survival experience of children enrolled on cancer clinical trials may not reflect the full range of patients treated in community settings. The current study evaluated 5-year survival and 10-year conditional survival for RMS from U.S. population-based cancer registry data.

METHODS

Public-use data from the Surveillance, Epidemiology, and End Results (SEER) program were used in life table and Cox regression analyses to evaluate RMS survival by patient age at diagnosis, gender, tumor histology, tumor site and stage, and major treatment eras among 848 children who were age < 20 years at the time of diagnosis, were a resident of 1 of 9 geographic reporting regions, and were diagnosed between 1973 and 2000.

RESULTS

The 5-year survival probabilities were found to be highest for younger-age children (ages 1-4 years: 77%), patients with localized disease (83%), those whose tumors had an embryonal histology (67%), and patients with orbital (86%) and genitourinary (80%) tumor sites. Poor prognosis was associated with diagnosis during infancy (47%) and adolescence (48%); metastatic disease at the time of presentation (31%); alveolar histology (49%); and tumors of the extremities (50%), retroperitoneum (52%), and trunk (52%). Conditional 10-year survival probabilities among those who survived > or = 5 years were 85% or higher. The probability of survival by stage at the time of diagnosis increased with each successive treatment era, suggesting a stage shift phenomenon over time.

CONCLUSIONS

Large variations in 5-year survival were evident depending on patient age and tumor characteristics. However, children who survived the first 5 years after diagnosis were found to have an excellent long-term prognosis. The patterns in RMS survival noted from the current population-based evaluation did not appear to differ substantially from those previously reported by major clinical trials.

Childhood cancer patients' access to cooperative group cancer programs: a population-based study

BACKGROUND

The Children's Oncology Group (COG), a merger of the Children's Cancer Group (CCG) and the Pediatric Oncology Group (POG), conducts clinical trials for the treatment of childhood cancer. To assess the feasibility of developing a nationwide childhood cancer registry, the authors attempted to determine whether COG could serve as a resource for identifying all children with cancer.

METHODS

A consolidated file of children age < 20 years who were diagnosed with cancer between 1992-1997 and registered with either CCG or POG was linked with records from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program. Age-specific registration rates and age-adjusted registration rates (AARR) were calculated overall and by year of diagnosis, gender, race/ethnicity, stage of disease at diagnosis, and type of cancer.

RESULTS

Of 10,108 children age < 20 years with cancer who were identified by the 11 SEER registries between 1992-1997, 5796 were registered with CCG or POG. The AARR was 71% for children age < 15 years, 24% for adolescents ages 15-19 years, and 57% for children age < 20 years. Registration rates were stable over the years studied, varied by geographic region, and were found to be higher among children with more advanced disease. Registration rates were highest for children with leukemia, hepatic tumors, and renal tumors, and were lowest for carcinoma and retinoblastoma.

CONCLUSIONS

The results of the current study demonstrate that not all children with cancer are registered by the cooperative groups; however, a national registry program can be achieved by supplementing cases identified through COG with data collected by statewide population-based cancer registries. Such a partnership would be mutually beneficial, allowing COG to achieve 100% registration of children with cancer and, for the statewide cancer registries, improving the timeliness of case-finding and follow-up information for cancer outcomes.

Originality, benefits and difficulties of clinical research performed by cooperative groups: the experience of an Italian Lung Cancer Study Group

In the past years, clinical research performed by cooperative groups achieved important results. The trials of adjuvant chemotherapy in breast and colorectal cancer or neoadjuvant treatment in osteosarcoma are cornerstones in the history of medical oncology and highlight the importance of research performed by cooperative groups. However, there are many difficulties for the functioning of cooperative groups: financial support, slow enrollment of patients in clinical trials, insurance related problems and quality control of clinical research. In the last few years, our group focused its interest on lung cancer, both small cell and non-small cell. The group is composed of experts from various disciplines in oncology. The clinical interest of the group has focused on two aspects of lung cancer: quality of life and treatment of elderly patients. Our group is giving significant contributions to the field of lung cancer. Today, large controlled clinical trials are ongoing.

Progress resulting from clinical trials. Solid tumors in childhood cancer

Solid tumors account for approximately 70% of malignant neoplasms in children younger than 15 years of age. The 5-year survival of children with solid tumors increased from 27% to 70% between 1960 and 1990. The slope of the curve that describes the change in survival over this period is remarkably constant, reflecting the nature of progress made through clinical trials. In addition to providing data important for the refinement of treatment for specific tumors, clinical trials have made numerous important, global contributions for the practice of oncology. The development of uniform response criteria, for example, was necessitated by clinical trials. The identification of histologic subtypes and the recognition of prognostic variables have permitted refinements in diagnosis and staging. By exploring novel strategies for the integration of different therapeutic modalities, clinical trials have identified indications for the use of presurgical chemotherapy, preradiation chemotherapy, and second-look and delayed primary surgeries. Refinements in the utilization of chemotherapy have been made possible by the evaluation of new agents, the study of dose intensity, and the use of the "window of opportunity" to identify active agents for tumors for which there is no effective treatment. Clinical trials have been instrumental in defining the late effects of treatment, investigating the causes of childhood cancer through epidemiologic studies, and supporting cancer biology research. The close collaboration of basic and clinical investigators offers the best opportunity for realizing the rewards of transitional research.

Trends in patterns of treatment of childhood cancer in Los Angeles County

To assess the proportion of children with cancer who have been managed by mainstream pediatric cancer programs, population-based cancer incidence data for Los Angeles County (LAC) children (under 20 years of age) for the years 1972 through 1987 were linked with patient records of children registered with the two national cooperative pediatric oncology groups, Children's Cancer Study Group and Pediatric Oncology Group. The proportion of children with cancer who were registered by cooperative groups increased markedly over time: 9% of LAC children younger than 15 years of age who were diagnosed with cancer in 1972 were registered with cooperative groups, compared to 52% of those diagnosed in 1980 and 62% of those diagnosed in 1987. Registration rates decreased with increasing age at cancer diagnosis. In the most recent time period, 1984-1987, 66% of LAC children diagnosed with cancer under age 5 years were registered with cooperative groups compared to 62% of those who were 5 to 9 years old and 49% of those who were 10 to 14 years old; although they were frequently diagnosed with tumors considered to be childhood cancers, only 19% of older adolescents (aged 15-19 years) were registered. In LAC, there was no apparent bias in registration rates with regard to gender or racial-ethnic background. Among patients diagnosed in the period 1984-1987, children in the highest of five socioeconomic status categories were underrepresented among registrants. Registration rates were highest (70% or greater) for patients with acute lymphocytic and acute nonlymphocytic leukemia, medulloblastoma, hepatoblastoma, Wilms tumor, and rhabdomyosarcoma. Fewer than 50% of patients with other brain and central nervous system tumors, retinoblastoma, other soft tissue sarcomas, and bone tumors were registered with the cooperative groups.