Cancer stem cells: an evolving concept.

The cancer stem cell (CSC) concept derives from the fact that cancers are dysregulated tissue clones whose continued propagation is vested in a biologically distinct subset of cells that are typically rare. This idea is not new, but has recently gained prominence because of advances in defining normal tissue hierarchies, a greater appreciation of the multistep nature of oncogenesis and improved methods to propagate primary human cancers in immunodeficient mice. As a result we have obtained new insights into why the CSC concept is not universally applicable, as well as a new basis for understanding the complex evolution, phenotypic heterogeneity and therapeutic challenges of many human cancers.

Effect of systematic education courses on rectal cancer treatments in a population.

Purpose: In a strategy aimed to improve perioperative and operative management of rectal cancer in British Columbia (BC), a series of educational events were provided for BC surgeons, radiation oncologists, and pathologists including teaching on the use of preoperative radiation, surgical technique with total mesorectal excision (TME), and pathology reporting. Seminars were offered during 2002 and 2003 each over 2 days with documented attendance from 30 hospitals in the province. We wished to determine whether frequency of preoperative radiation and TME surgery changed on a population level after the rectal cancer education courses in 2002 and 2003.

Early detection of patients with poor risk diffuse large B-cell lymphoma.

More than 60% of patients with diffuse large B-cell lymphoma (DLBCL) will be cured with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). However, the outcome following secondary therapies remains poor. Early identification of high-risk patients would allow alternative treatment strategies to be considered.

IPSS poor-risk karyotype as a predictor of outcome for patients with myelodysplastic syndrome following myeloablative stem cell transplantation.

The optimal therapy for myelodysplastic syndrome (MDS) is allogeneic bone marrow (BM) or blood (BSC) stem cell transplantation (SCT), although outcomes are limited by nonrelapse mortality (NRM) and relapse. A retrospective review was performed of 156 patients who underwent SCT (114 BM, 42 BSC) for MDS or secondary acute myelogenous leukemia (sAML) at our institution. Fifty-five patients remain in continuous complete remission: 35 BM recipients and 20 BSC recipients (median follow-up 139 and 89 months, respectively).

Involved-nodal radiation therapy as a component of combination therapy for limited-stage Hodgkin's lymphoma: a question of field size.

Purpose: Combined-modality therapy is the standard of care for limited-stage Hodgkin's lymphoma (HL). Radiation therapy has evolved from extended-field radiation therapy (EFRT) to involved-field radiation therapy (IFRT), reducing toxicity while maintaining high cure rates. Recent publications recommend a further reduction to involved-nodal radiation therapy (INRT), however, this has not been clinically validated.

Population-based analysis of incidence and outcome of transformed non-Hodgkin's lymphoma.

Purpose: To assess the incidence and predictive factors for development of transformed lymphoma in a population-based series of patients with follicular lymphoma (FL).

Patients And Methods: The Lymphoid Cancer Database was used to identify patients with FL diagnosed and treated in the province of British Columbia, Canada. Transformed lymphoma was defined as the development of aggressive non-Hodgkin's lymphoma (NHL) in patients with FL.

In vivo optical coherence tomography imaging of preinvasive bronchial lesions.

Purpose: Optical coherence tomography (OCT) is an optical imaging method that can visualize cellular and extracellular structures at and below tissue surface. The objective of the study was to determine if OCT could characterize preneoplastic changes in the bronchial epithelium identified by autofluorescence bronchoscopy.

Experimental Design: A 1.

The impact of new chemotherapeutic and hormone agents on survival in a population-based cohort of women with metastatic breast cancer.

Background: Over the past decade, a number of new therapeutic agents have become available in the treatment of metastatic breast cancer (MBC). This study characterized the use and assessed the impact on survival of population-based access to new agents for the treatment of MBC.

Methods: The dates of release in British Columbia of 7 new systemic agents for MBC during the 1990s were used to construct 4 time cohorts.

Long-term outcome of myeloablative allogeneic stem cell transplantation for multiple myeloma.

Allogeneic stem cell transplantation (alloSCT) has been used in the hopes of harnessing the curative potential of the graft-versus-myeloma effect. This study examines the long-term outcomes of a large cohort of patients with myeloma who were treated with myeloablative alloSCT at a single center. Comparisons are made with those who were treated with autologous stem cell transplantation (ASCT).

A systematic evaluation of the ataxia telangiectasia mutated gene does not show an association with non-Hodgkin lymphoma.

The ataxia telangiectasia mutated (ATM) gene is critical for the detection and repair of DNA double-stranded breaks. Mutations in this gene cause the autosomal recessive syndrome ataxia telangiectasia (AT), an attribute of which is an increased risk of cancer, particularly lymphoma. We have undertaken a population-based case/control study to assess the influence of genetic variation in ATM on the risk of non-Hodgkin lymphoma (NHL).

The revised International Prognostic Index (R-IPI) is a better predictor of outcome than the standard IPI for patients with diffuse large B-cell lymphoma treated with R-CHOP.

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous entity, with patients exhibiting a wide range of outcomes. The addition of rituximab to CHOP chemotherapy (R-CHOP)has led to a marked improvement in survival and has called into question the significance of previously recognized prognostic markers. Since randomized controlled trials of R-CHOP in DLBCL have included select subgroups of patients, the utility of the International Prognostic Index (IPI) has not been reassessed.

Evolving approaches to primary treatment of Hodgkin lymphoma.

Two challenges confront the clinician treating Hodgkin lymphoma today: achieving a high level of effectiveness while minimizing toxicity. At least 80% of patients can be cured with currently available chemotherapy regimens, augmented in selected patients with the addition of involved field radiation or intensified chemotherapy assisted by granulocyte growth factors or stem cell transplantation. Major late toxicity including infertility, premature menopause, cardiovascular disease and second neoplasms can be avoided in most patients if the treatment program is chosen carefully.

Locoregional recurrence risks in elderly breast cancer patients treated with mastectomy without adjuvant radiotherapy.

This study examined tumour and treatment characteristics in elderly women treated with mastectomy without radiotherapy and compared their outcomes to younger counterparts. Data were analysed for 2362 women aged 50 years and older referred to the British Columbia Cancer Agency, Canada between 1989 and 1997. The women had invasive T1-4, N0-N3, M0 breast cancer treated with mastectomy without adjuvant radiotherapy.

Incidence and spectrum of non-Hodgkin lymphoma in Chinese migrants to British Columbia.

The incidence and spectrum of non-Hodgkin lymphoma (NHL) differ between the Chinese and Caucasian populations. Using population-based registries, we studied the pattern of NHL in Chinese migrants to British Columbia (BC). The records of all NHL cases of Chinese descent diagnosed between 1980 and 1997 were retrieved.

Characteristics and outcome of patients developing endocarditis following hematopoietic stem cell transplantation.

Endocarditis is an uncommon complication of hematopoietic stem cell transplantation (HSCT). A retrospective review of 1547 patients who underwent HSCT in Vancouver between January 1986 and December 2001 was performed. In all, 20 cases of endocarditis were identified (1.

A randomized phase IIb trial of pulmicort turbuhaler (budesonide) in people with dysplasia of the bronchial epithelium.

Purpose: Preclinical studies suggest that inhaled budesonide may be an effective chemopreventive agent for lung cancer. We conducted a phase IIb study to determine the effects of inhaled budesonide in smokers with bronchial dysplasia.

Experimental Design: A total of 112 smokers with more than or equal to one site of bronchial dysplasia > 1.

Characterization of peripheral T-cell lymphomas in a single North American institution by the WHO classification.

Background: All peripheral T-cell lymphomas (PTCLs) diagnosed at a single institution were evaluated to determine the unique clinical features and outcome of specific entities and test the predictive validity of the International Prognostic Index (IPI).

Patients And Methods: Cases of PTCL seen at the British Columbia Cancer Agency between 1981 and 2000 were identified. Pathologic material was re-assessed and classified according to the WHO classification, and patients were staged and treated uniformly according to era-specific guidelines.

Molecular pathogenesis of mucosal-associated lymphoid tissue (MALT) lymphoma.

Extranodal marginal zone B-cell lymphomas of mucosal-associated lymphoid tissue (MALT)-type occur in a number of anatomic sites, but share overlapping morphological and immunophenotypic features. Helicobacter pylori infection has been identified as an etiological factor in gastric MALT lymphoma, but the cause of MALT lymphomas at other sites remains a matter of speculation. Despite these limitations in understanding the etiology of MALT lymphoma, standard cytogenetic analysis has proved useful by demonstrating similar alterations in MALT lymphomas from different anatomic sites.

Interpretation of p53 immunoreactivity in endometrial carcinoma: establishing a clinically relevant cut-off level.

There is accumulating evidence that immunohistochemical staining for p53 can identify patients with endometrial carcinoma who have an adverse outcome, but the interpretation of existing data is complicated by differences between studies in the way that p53 immunohistochemistry results have been assessed. In this study, we sought to determine the appropriate cut-off level for stratification of patients with endometrial carcinoma into high- and low-risk groups, based on p53 immunohistochemical staining. A total of 200 cases of endometrial carcinoma treated by hysterectomy were retrieved from the archives of the Department of Pathology, Vancouver General Hospital, from the period 1983 to 1998.

Hodgkin's lymphoma in Chinese migrants to British Columbia: a 25-year survey.

Background: Compared with the West, Hodgkin's lymphoma in Oriental countries is characterized by a lower incidence rate and a higher proportion of mixed cellularity histology. Both environmental and genetic factors may be involved.

Patients And Methods: The incidence and pattern of pathology of Hodgkin's lymphoma in the migrant Chinese population (0.

Adjuvant radiation therapy after breast-conserving surgery in elderly women with early-stage breast cancer: controversy or consensus?

Breast-conservation therapy (BCT), which consists of breast-conserving surgery (BCS) and postoperative radiation therapy (RT), provides similar levels of local control and survival compared with mastectomy. Although the incidence of breast cancer increases with age and the proportion of elderly women in the population continues to increase, clinical trials of BCT have included few women aged > or = 65 years, limiting the ability to establish clear consensus regarding optimal therapy in this population. This article examines the literature on BCT in elderly women with early-stage breast cancer.

The quality of community colposcopic practice.

Objective: To estimate the quality of community colposcopic practice in British Columbia through an assessment of the degree of correlation between colposcopy, cytology, and histology.

Method: We reviewed all new-patient colposcopies in British Columbia during 2001 by 37 gynecologists in 24 hospital-based clinics.

Results: Colposcopic impression closely mirrored the referral cytology diagnosis in 89.

Key issues in lung cancer chemoprevention trials of new agents.

Lung cancer is a major health problem world-wide. Former heavy smokers retain a significant risk for lung cancer after smoking cessation. With a large population of current and former smokers at risk, an alternative cancer control strategy such as chemoprevention needs to be developed to reduce lung cancer mortality especially for smokers who have followed medical advice to give up smoking.