Primary Care Physicians' Decision Making Regarding Initial Oncology Referral for Adolescents and Young Adults With Cancer

PURPOSE

The objectives of this study were to determine whether pediatricians are more likely than other primary care physicians (PCPs) to refer newly diagnosed adolescent and young adult patients with cancer to pediatric oncological specialists, and to assess the physician and patient characteristics that affect patterns of referral.

METHODS

A cross-sectional vignette survey was mailed to PCPs to examine hypothetical referral decisions as a function of physician characteristics and patient characteristics, including diagnosis, age, gender, race/ethnicity, family support, transportation, insurance, and patient preference for site of care. Pediatrician PCPs and nonpediatrician PCPs (family medicine, internal medicine, and emergency medicine physicians) practicing in North Carolina and in Washington State participated in the study.

RESULTS

A total of 406 surveys were completed (35.8% response rate). Sixty percent of pediatric PCPs referred their hypothetical patients with cancer to pediatric specialists (PSs), compared with only 37% of nonpediatric PCPs. Patient age also influenced referral patterns; 89% of 13-year-olds, 74% of 16-year-olds, 25% of 19-year-olds, and only 9% of 22-year-old patients were referred to a PS. Multivariate logistic regression demonstrated that diagnosis and physician practice setting also were associated with referral patterns.

CONCLUSIONS

Both patient age and PCP specialty were significant predictors of referral patterns in hypothetical vignettes of newly diagnosed adolescent and young adult patients with cancer. Pediatricians were more likely than nonpediatrician PCPs to refer patients to a PS. Referrals to PSs decreased dramatically between ages 16 and 19. Because the site of oncological care can impact outcomes, these data have the potential to inform awareness and education initiatives directed at PCPs.

Treatment of Burkitt lymphoma in children and adults: Lessons from Africa

Modern chemotherapy for childhood Burkitt lymphoma has its origins in Africa, where treatment evolved from one or two doses of single agents, which were curative in some patients, to combinations of non-cross-resistant drugs. Subsequently, in Europe and the United States, high-dose methotrexate, high-dose cytarabine, etoposide, and ifosfamide were found to be active in children with recurrent disease and were incorporated into primary therapy for patients with high-risk disease. These third-generation protocols produce overall cure rates around 90%. Therapy regimens for adults with Burkitt lymphoma have been developed by modifying second-generation pediatric protocols, and few investigators have used the third-generation pediatric regimens that include higher doses of methotrexate and additional agents. The weight of evidence strongly suggests that high-dose therapy with stem cell rescue in first remission cannot substitute for intensive therapy from the outset. Tolerance of intensive regimens by the elderly is a legitimate concern, but it seems appropriate to modify therapy only when necessary in individual patients. The value of rituximab and granulocyte colony-stimulating factor in patients undergoing intensive therapy (particularly the elderly) is worthy of further exploration. Because childhood diffuse large-B-cell leukemia (DLBCL) responds equally well to therapy for Burkitt lymphoma, more intensive therapy and intensive support might also give better results in at least a subset of adults with advanced DLBCL-perhaps defined on the basis of limited molecular profiling, which has provided new information about the categories of aggressive B-cell lymphomas.

Lymphoma in adolescents and young adults

Non-Hodgkin (NHL) and Hodgkin (HL) lymphomas are represented prominently in the adolescent and young adult (AYA) population. These diseases represent 11% of total cancer diagnoses in children, 4% in those 40 years of age and older, and 13% in AYA (aged 15-39 years). Although age-adjusted incidence rates of NHL increase with age, the more aggressive lymphomas are seen more commonly in the younger population with a transition to low-grade, indolent subtypes as the population ages. Burkitt lymphoma, diffuse large B-cell lymphoma, lymphoblastic lymphoma, and anaplastic large cell lymphoma make up the most common subtypes in the AYA population, although within the subgroup age 30-39 years, follicular lymphoma becomes more prominent. As a result, much of the armamentarium in the treatment of aggressive NHL and HL in adults is based on data from pediatric clinical trials. There are obvious limitations to this approach. It is vital that we gain a more thorough understanding of the biology and therapeutic responsiveness of NHL and HL in the AYA population. Thus, we must leverage the large prospective and retrospective trials that have been completed to date and redirect our approaches to cancer care in this unique population. We review the epidemiological data on NHL and HL from the Surveillance, Epidemiology and End Results registries as a cornerstone for a comparative analysis of therapeutic outcomes available in this population.

Estimation of the relationship between caspase-3 expression and clinical outcome of Burkitt's and Burkitt-like lymphoma

Burkitt's lymphoma and atypical Burkitt/Burkitt-like lymphoma (BL/BLL) are considered highly aggressive B-cell lymphomas with a rapid proliferative rate and high rate of apoptosis. The aim of the present study was to confirm whether apoptotic and cell proliferative factors affect BL/BLL clinical outcomes. We retrospectively analyzed the relationship between the clinical and immunophenotypic features of 43 BL/BLL patients by immunohistochemical staining for bcl-2 and double staining for Ki-67 plus caspase-3. In double staining experiments, all patients were divided into high and low groups for the expression of caspase-3, Ki-67, and both Ki-67 and caspase-3, by using the medians of their percentages as limits. The 43 BL/BLL patients were divided into high caspase-3 (n = 19) and low caspase-3 (n = 24) groups. There was a significant difference in the overall survival between the high (77%) and low caspase-3 (33%) groups; the survival rate of patients in the low caspase-3 group who received aggressive short-term chemotherapy (58%) was significantly better than that of patients who received cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP) therapy (17%). All patients positive for bcl-2 were in the low caspase-3 group (high caspase-3 group, 0%; low caspase-3 group, 42%). The overall survival tended to be better in the high caspase-3 and bcl-2-negative group (76%) than in the low caspase-3 and bcl-2-negative (50%) group. In addition, the low caspase-3 and bcl-2-positive group tended to show the worst prognosis (16%). We suggest that caspase-3 may function as an indicator of the prognosis of BL/BLL. Furthermore, intensive short-term chemotherapeutic regimens may improve the prognosis of the patients in the low caspase-3 group.

High-grade mature B-cell lymphoma with Burkitt-like morphology: results of a clinicopathological study of 72 Japanese patients

The aim of the present study was to estimate optimum chemotherapeutic regimens for high-grade mature B-cell lymphoma cases with Burkitt-like morphology (Burkitt's lymphoma [BL]/Burkitt-like lymphoma [BLL]) patients. We analyzed 72 BL/BLL, including 36 with the c-myc translocation (molecular BL [mBL]), 20 without it (mBL-like), and 16 in whom we were uncertain regarding the existence of the c-myc translocation, and compared them with 182 diffuse large B-cell lymphoma (DLBCL) cases. On clinical and immunophenotypic analysis, the typical BL immunophenotype (CD10 positive, bcl-2 negative, and Ki-67 index >or=95%) was noted in 23 (66%) and 11 (55%) of the 35 mBL and 20 mBL-like patients, respectively. The presence of the c-myc translocation and typical immunophenotype in BL did not affect the overall survival of BL/BLL. There were no significant differences between the overall survival of DLBCL (45%) and BL/BLL (50%, P = 0.85). However, the overall survival of BL/BLL patients who received cyclophosphamide, doxorubicin, vincristine, and prednisolone-related therapy (22%) was significantly lower than that of DLBCL patients (P = 0.01). In contrast, the overall survival of BL/BLL patients who received aggressive short-term chemotherapy (75%) was better than that of the patients who received cyclophosphamide, doxorubicin, vincristine, and prednisolone therapy (P < 0.01). The finding was confirmed by multivariate analysis (hazard ratio 4.4; confidence interval 2.0-9.7; P = 0.0003). We concluded that aggressive short-term chemotherapy improves survival in BL/BLL, regardless of its genetic and immunophenotypic features.

Gastric Burkitt lymphoma is a distinct subtype that has superior outcomes to other types of Burkitt lymphoma/leukemia

Burkitt lymphoma/leukemia (BL) is a highly aggressive non-Hodgkin's lymphoma (NHL) often presenting in extranodal sites or as an acute leukemia. Because of the shared molecular and genetic features, the World Health Organization classification of lymphoid diseases recognizes the lymphomatous and leukemic phases of BL as a single entity: a mature B cell neoplasm, subtype Burkitt lymphoma/Burkitt cell leukemia. Because BL frequently appears in the stomach, we investigated the clinical presentation and outcome of gastric BL. We discovered 21 patients with gastric BL through a survey of our NHL registry, and retrospectively analyzed the distinct features of BL, including the St Jude/Murphy staging, other extranodal involvement, morphology and immunophenotype, response to treatment, and clinical outcome. The patients' median age was 48 years (range, 7-75), and the male-to-female ratio was 2.5. Stage 1 was found in five patients, stage 2 in five patients, and stage 4 in 11 patients. The stomach body and antrum were most frequently involved. All 21 patients were treated with systemic intensive chemotherapy, producing a 71% (15/21) rate of complete response (CR) to chemotherapy. Both the 2-year disease-free and overall survival rates were 55%. All ten patients in BL stages 1 and 2 showed outstanding outcomes, and nine of the ten patients exhibited CR and long-term survival. These data show that a high proportion of patients with gastric BL have a localized disease that is limited to stage 1 and 2, and that these localized BLs have outstanding outcomes. These findings suggest that these BLs could represent a distinct subtype that might have a different biology, which needs to be defined.

Gender and age-related differences in Burkitt lymphoma--epidemiological and clinical data from The Netherlands

Although Burkitt's lymphoma (BL) is classified as one entity in the World Health Organisation (WHO) classification, we wondered whether BL should not be considered as a different disease in children compared with adults. Netherlands Cancer Registry (NCR) data were obtained from 1994 to 1998 (n=203). Detailed clinical data from two treatment protocols were compared: one for adults up to the age of 65 years (n=27) and one for children (n=80). All slides of the two clinical studies were centrally reviewed which included immunophenotyping and when necessary breakpoint analysis of MYC/8q24. Only cases with an unambiguous diagnosis of BL (classical and atypical BL) were accepted. The age distribution of BL-patients showed a bimodal distribution with a peak at the paediatric age and a steady increase after approximately 60 years of age. Most of the patients were males (89% for children and 78% for adults) and only male patients showed this bimodality. Children more often had extranodal disease (81% vs. 59%), whereas adults more often had nodal disease (89% vs. 53%). Based on epidemiology and clinical presentation, the concept that BL is one disease should be re-challenged.

Adult Burkitt leukemia and lymphoma

The World Health Organization Classification of Lymphoid Neoplasms identifies Burkitt lymphoma/leukemia as a highly aggressive mature B-cell neoplasm consisting of endemic, sporadic, and immunodeficiency-associated variants. These subtypes share many morphologic and immunophenotypic features, but differences exist in their clinical and geographic presentations. All of these subtypes possess chromosomal rearrangements of the c-myc oncogene, the genetic hallmark of Burkitt lymphoma that contributes to lymphomagenesis through alterations in cell cycle regulation, cellular differentiation, apoptosis, cellular adhesion, and metabolism. Brief-duration, high-intensity chemotherapy regimens containing aggressive central nervous system prophylaxis have had remarkable success in the treatment of this disease, with complete remission rates of 75% to 90% and overall survivals reaching 50% to 70% in adults. Although Burkitt lymphoma cells are extremely chemosensitive, biologically targeted therapies should be developed because current treatment options are suboptimal for patients with poor prognostic features or in the setting of relapsed disease.

Burkitt's lymphoma: single-centre experience with modified BFM protocol

Burkitt's lymphoma is a rare aggressive lymphoma, which responds poorly to standard chemotherapy regimens used to treat high-grade non-Hodgkin's lymphoma (NHL). The use of intensive chemotherapy protocols using alkylating agents and intensive CNS prophylaxis has dramatically altered prognosis. We have treated eight patients with Burkitt's lymphoma with a modified BFM protocol. The dose of methotrexate was reduced from 5 g/m2 to 1.5 g/m2 with the aim of reducing toxicity. Seven patients received a total of six cycles of chemotherapy each and one patient received five cycles of chemotherapy. Each cycle included high-dose methotrexate, an alkylating agent (ifosphamide or cyclophosphamide) and two triple intrathecal injections of chemotherapy. Two patients with bulky abdominal disease in addition received an autologous stem cell transplant. The regimen was well tolerated with minimal toxicity. At a median follow-up of 16 months (range 10-28), six of the eight patients (75%) were alive and in complete remission. Two patients relapsed, one 24 months post-BFM chemotherapy and the other 1-month post-autologous stem cell transplantation and 2 months post-BFM chemotherapy.