PARP Inhibitors in Prostate Cancer

Treatment of metastatic prostate cancer has evolved significantly over the past decade. Palliative therapy has, historically, consisted of androgen deprivation, chemotherapy and different radiation therapy approaches. More recently, breakthrough therapy with the use of poly-ADP-ribose polymerase (PARP) inhibitors has led to significant improvement in the outcome of patients with metastatic prostate cancer who harbor certain genetic mutations. This concise review focuses on the 3 PARP inhibitors that have shown activity in metastatic prostate cancer.

Evaluating ivosidenib for the treatment of relapsed/refractory AML: design, development, and place in therapy

Improvements in the last decade in understanding the molecular mechanisms underlying acute myeloid leukemia (AML) have emphasized that treatment regimens should be personalized with agents that can selectively target genetic abnormalities if present. Neomorphic mutations in isoform 1 of isocitrate dehydrogenase (IDH1) result in the formation of the onco-metabolite R-2-hydroxyglutarate, which drives leukemic transformation by affecting processes such as chromatin remodeling, the cellular defense against oxidative stress and cell survival. Preclinical studies with small molecule inhibitors have validated mutant IDH1 as a molecular target, and a recent Phase 1 clinical trial with the first mutant IDH1 inhibitor ivosidenib has prompted approval by the US Food and Drug Association for the treatment of patients with IDH1-mutated AML in the relapsed and refractory setting due to impressive results. This approval has given a group of patients, that otherwise has a very poor prognosis and limited options, new hope, and it is to be expected that more indications for ivosidenib will follow soon. These developments highlight the potential of precision medicine in AML, with more agents currently under evaluation in clinical trials. Although the first reports have also already emerged describing acquired resistance for these mutant IDH inhibitors, combination treatment might overcome this problem, which could drastically change the treatment landscape of AML over the next few years.

Directed Therapies in Anaplastic Lymphoma Kinase-rearranged Non-small Cell Lung Cancer

Anaplastic lymphoma kinase (ALK) rearrangements were first implicated as driving mutations in non-small cell lung cancer in 2007. Since then, a number of novel, small-molecule inhibitors directed against the ALK receptor have demonstrated superiority over standard chemotherapies in the treatment of ALK rearrangement-positive lung cancer. Of considerable importance when considering such therapies is the ability of each to overcome mutations conferring acquired resistance, as well as penetrate the central nervous system (CNS), the most common site of metastasis and traditionally the most difficult to breach. Herein is a review of the efficacy, indications, and degree of CNS penetration for the ALK-targeting agents crizotinib, ceretinib, alectinib, brigatinib, and lorlatinib, as well as a summary of ongoing clinical trials comparing these drugs.

Chronic Lymphocytic Leukemia: Current Concepts

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in adults, and while in early, asymptomatic stages treatment is not indicated, the threat to the quality of life and increased mortality of patients posed by more advanced-stage disease necessitate therapeutic intervention. Guidelines of when and how to treat are not well-established because CLL is a disease of the elderly and it is important to balance preservation of functional status and control of the disease. Advances in molecular and genetic profiling has led to the ability to identify sub-groups of patients with CLL whose disease may respond to selected therapy. This review discusses current standard therapies in the major sub-groups of CLL based on age and functional status, in both the front-line and relapsed/refractory settings. It also provides a concise review of novel agents that have shown considerable efficacy in CLL.

Erdheim-Chester disease: a comprehensive review

Erdheim-Chester disease is a rare form of non-Langerhans' cell histiocytosis characterized by multi-system infiltration by xanthogranulomas composed of foamy histiocytes surrounded by fibrosis. Approximately 400 cases have been reported in the literature, and the recent increase in the number of cases is likely due to the increased awareness of its associated morbidity and mortality. The etiology of this disease remains unknown, the clinical course is variable and treatment is still not well-established. The objective of this review is to describe the pathogenesis, clinical manifestations, and diagnosis of this rare disorder, and to review its prognosis and treatment. Erdheim-Chester disease (ECD) is a rare form of non-Langerhans' cell histiocytosis. It was first described in 1930. Approximately 400 cases have been reported in the literature.

Complications of allogeneic hematopoietic stem cell transplantation

Infection, graft-versus-host disease (GVHD), and to a lesser extent sinusoidal obstructive syndrome (SOS) represent the major causes of morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation (AHSCT). During the last decade, progress in prevention and treatment of these complications led to improvement in the outcome of these patients. Despite the fact that nonmyeloablative regimens have been increasingly used in elderly patients and in patients with co-morbidities, the nonrelapse related mortality remains a challenge and long-term follow-up is required. The objective of this manuscript is to provide an updated concise review of the complications of AHSCT and of the available treatment interventions.

Clinical utility and therapeutic implications of oncotype analysis in patients with breast cancer

e11084

Background: Oncotype DX is a 21-gene assay developed for early stage, hormone receptor positive breast cancer that generates a Recurrence Score which estimates response to chemotherapy and the likelihood of systemic recurrence at 10 years. It differentiates between patients who would benefit from chemotherapy plus hormonal therapy versus hormonal therapy alone. This study’s goal was to determine if the Recurrence Score affected clinical management at our institution and physicians’ accuracy at predicting Recurrence Scores. Methods: A retrospective review was conducted of 116 breast cancer patients treated over a 7 year period. Clinic notes, pathology reports, and additional relevant information were presented to breast surgeons, oncologists, radiation oncologists, and surgical pathologists. Individual physicians estimated recurrence risks and recommended treatment based on those estimates. The Recurrence Score was revealed and changes in therapeutic recommendations were recorded. Results: Treatment recommendations changed in 43% of patients. 29% had a change from chemotherapy followed by hormone therapy to hormone therapy alone due to a low recurrence score, while 14% initially recommended hormonal therapy were changed to chemotherapy plus hormonal therapy due to an intermediate range score. Surgical oncologists accurately predicted Recurrence Scores 52% of the time, medical oncologists 46%, radiation oncologists 45%, and surgical pathologists 15%. A nested mixed model showed that pathologists were statistically significantly worse at predicting recurrence scores than surgical oncologists, medical oncologists, and radiation oncologists. Conclusions: The Oncotype DX assay changes management of breast cancer patients at our institution, frequently downgrading the intensity of systemic therapy. Clinicians were able to accurately estimate recurrence categories about 50% of the time. We recommend the use of Oncotype DX assay along with assessment of clinicopathologic features of an individual’s disease in eligible patients to enhance the selection of appropriate adjuvant therapy.

Prognostic implications of genetic aberrations in acute myelogenous leukemia with normal cytogenetics

Acute myelogenous leukemia (AML) is a genetically heterogeneous disease in which somatic mutations, that disturb cellular growth, proliferation, and differentiation, accumulate in hematopoietic progenitor cells. Cytogenetic findings, at diagnosis, have been proven to be one of the most important prognostic indicators in AML. About half of the patients with AML are found to have "normal" cytogenetic analysis by standard culture techniques. These patients are considered as an intermediate risk group. Cytogenetically normal AML (CN-AML) is the largest cytogenetic risk group, and the variation in clinical outcome of patients in this group is greater than in any other cytogenetic group. Besides mutation testing, age and presenting white blood cell count are important predictors of overall survival, suggesting that other factors independent of cytogenetic abnormalities, contribute to the outcome of patients with AML. The expanding knowledge at the genetic and molecular levels is helping define several subgroups of patients with CN-AML with variable prognosis. In this review, we describe the clinical and prognostic characteristics of CN-AML patients as a group, as well as the various molecular and genetic aberrations detected in these patients and their clinical and prognostic implications.

Hairy cell leukemia: current concepts

Hairy cell Leukemia (HCL) is a chronic lymphoproliferative disorder that was characterized in the late 1950s. HCL is defined, according to the WHO classification, as a mature (peripheral) B-cell neoplasm (1). HCL accounts for between 2-3% of all leukemia cases, with about 600 new cases diagnosed in the U.S. each year (1). HCL occurs more commonly in males, with an overall male to female ratio of approximately 4:1. The median age of onset is 52 years. This disease is seen more commonly in Caucasians and appears to be especially frequent in Ashkenazi Jewish males, with rare occurrence in persons of Asian and African descents (1). Hairy cells are distinct, clonal B cells arrested at a late stage of maturation. They are small B lymphoid cells that possess oval nuclei and abundant cytoplasm with characteristic micro-filamentous ("hairy") projections. They strongly express CD103, CD22, and CD11c (2). These cells typically infiltrate the bone marrow, the spleen, and to a lesser extent the liver, lymph nodes, and skin. Many patients present with splenomegaly and pancytopenia. Other clinical manifestations include recurrent opportunistic infections and vasculitis. Historically, HCL was considered uniformly fatal (2). However, recent treatment advances, using purine analogues such as Cladribine and Pentostatin, led to a significant improvement in prognosis with achievement of high response rates and durable remissions (2).

Dendritic cell neoplasms: an overview

Dendritic cell neoplasms are rare tumors that are being recognized with increasing frequency. They were previously classified as lymphomas, sarcomas, or histiocytic neoplasms. The World Health Organization (WHO) classifies dendritic cell neoplasms into five groups: Langerhans' cell histiocytosis, Langerhans' cell sarcoma, Interdigitating dendritic cell sarcoma/tumor, Follicular dendritic cell sarcoma/tumor, and Dendritic cell sarcoma, not specified otherwise (Jaffe, World Health Organization classification of tumors 2001; 273-289). Recently, Pileri et al. provided a comprehensive immunohistochemical classification of histiocytic and dendritic cell tumors (Pileri et al., Histopathology 2002;59:161-167). In this article, a concise overview regarding the pathological, clinical, and therapeutic aspects of follicular dendritic, interdigitating dendritic, and Langerhans' cell tumors is presented.

Complementary and alternative medicine in breast cancer patients

OBJECTIVE

Complementary and Alternative Medicine (CAM) is becoming increasingly popular among cancer patients, in particular those with breast cancer. It represents one of the fastest growing treatment modalities in the United States. Therefore, knowledge of CAM therapies is becoming necessary for physicians and other health care providers. CAM encompasses a wide range of modalities including special diet and nutrition, mind-body approaches, and traditional Chinese medicine.

METHODS

We reviewed the biomedical literature on CAM use in breast cancer patients, using Medline search from 1975 until 2002. In addition, consensus reports and books on CAM and breast cancer were included in the review. We evaluated the prevalence of CAM use in breast cancer patients, the reasons cited for its use, the different available modalities, and the reported outcomes.

RESULTS

Use of CAM in breast cancer patients ranges between 48% and 70% in the United States. The most commonly used CAM modalities include dietary supplements, mind-body approaches, and acupuncture. The reasons cited for using CAM were to boost the immune system, improve the quality of life, prevent recurrence of cancer, provide control over life, and treat breast cancer and the side effects of treatment. Several studies reported favorable results including improved survival, better pain control, reduced anxiety, improvement in coping strategies and significant efficacy in treating nausea and vomiting. Other less well-organized trials have reported either no benefit or negative effect of CAM and potential toxicity of some commercial products.

SIGNIFICANCE OF RESULTS

CAM is a growing field in health care and particularly among breast cancer patients. Knowledge of CAM by physicians, especially oncologists, is necessary. Oncologists should be willing to discuss the role of CAM with their patients and encourage patients to participate in well-organized research about CAM.

Current concepts in allogeneic hematopoietic stem cell transplantation

Progress in allogeneic SCT will depend on several factors including the advances in the conventional treatment of diseases treated currently with allogeneic SCT, the expansion of the donor pool, the selective control of GVHD, the development of more effective and less toxic preparative regimens to eradicate the neoplastic cell population, the characterization of a new generation of hematopoietic growth factors and cytokines and the development of newer and safer techniques for ex-vivo manipulation of stem cells. The use of hematopoietic growth factor-mobilized donor progenitor cells collected from the peripheral blood has been associated with a rapid hematopoietic engraftment without an increase in the incidence of acute GVHD compared to allogeneic BMT, an increased donor acceptance, elimination of the risk of general anesthesia and a decreased cost. The use of nonmyeloablative conditioning regimens prior to SCT represents a novel treatment approach that may lead to reduced toxicity and an extended use of this treatment in older patients and those with co-morbid conditions and in the treatment of malignant and non-malignant disorders. This approach may play a role in inducing tolerance for solid organ transplantation and in utilizing the GVM effect to treat solid tumors that are not fully responsive to myeloablative cytotoxic regimens. The optimal intensity of cytoreduction and immunosuppression is not well defined. GVHD and disease recurrence remain a challenge. Promising results have been reported in patients with refractory hematologic malignancies as well as in metastatic renal cell cancer, but the ultimate role of this treatment modality remains to be defined pending prospective, well designed, randomized trials.

Nonmyeloablative therapy and allogeneic hematopoietic stem cell transplantation

The toxicities associated with conventional myeloablative therapy and allogeneic hematopoietic stem cell transplantation (SCT) limit the use of this potentially curative approach to relatively healthy young patients. The risk of treatment-related morbidity and mortality with conventional allogeneic SCT ranges from 10% to 50%, depending on the age of the patient, HLA histocompatibility, diagnosis and disease status, and presence or absence of comorbid conditions. The main goals of conventional high-dose preparative regimens are to eradicate the malignancy and induce adequate host immunosuppression to prevent graft rejection. However, accumulated data indicate that the currently used myeloablative regimens frequently do not eradicate the malignant clone, and that an immune-mediated effect between donor immunocompetent T lymphocytes and host tumor cells seems to induce a major therapeutic benefit, accounting for the significantly lower incidence of leukemic relapse seen with allogeneic SCT compared to autologous or syngeneic SCT. These observations have led to the development of newer treatment modalities focusing on the induction of host tolerance to donor cells followed by the administration of scheduled donor T-lymphocyte infusions. Preliminary clinical data are encouraging but need to be confirmed in well-designed prospective controlled trials with direct comparison to conventional allogeneic SCT and extended follow-up to determine the durability of responses and the consequences of late complications such as chronic graft-vs-host disease on the patient's quality of life.

Allogeneic hematopoietic stem cell transplantation: complications and results

Acute complications such as veno-occlusive disease of the liver, acute and chronic graft-vs-host disease (GVHD), and infectious conditions remain major obstacles for the success of allogeneic hematopoietic stem cell transplantation (HSCT). Progress in allogeneic HSCT depends on several factors, including the adequate prevention and management of associated complications, advances in the conventional management of diseases currently treated with allogeneic HSCT, expansion of the donor pool, selective control of GVHD, development of more effective preparative regimens to eradicate the neoplastic cell population, characterization of a new generation of hematopoietic growth factors and cytokines, and development of newer techniques for ex vivo manipulation of stem cells. Hematopoietic growth factor-mobilized donor progenitor cells collected from peripheral blood have been shown to be associated with rapid hematopoietic engraftment without an increase in the incidence of acute GVHD compared with allogeneic bone marrow transplantation. Implementation of this approach will enhance donor acceptance, eliminate the risk of general anesthesia, decrease cost, and reduce the risk of infectious complications by reducing the duration of neutropenia. Nonmyeloablative allogeneic stem cell transplantation represents a novel treatment approach that may lead to reduced toxic effects and extended use of this treatment in older patients and in those with malignant and nonmalignant disorders. However, GVHD and disease recurrence remain a challenge. Promising results have been reported in patients with refractory hematologic malignancies and in metastatic renal cell cancer. Because late complications are commonly encountered in patients receiving allogeneic HSCT, lifelong observation is needed.

Nonsecretory multiple myeloma

Nonsecretory multiple myeloma (NSMM) is a rare variant of the classic form of multiple myeloma (MM) and accounts for 1% to 5% of all cases of MM. The clinical presentation and radiographic findings of NSMM and MM are the same. The diagnosis of MM requires the detection of a monoclonal gammopathy in the serum or urine. In NSMM, however, no such gammopathy can be demonstrated, making the diagnosis more difficult. We describe a 43-year-old African American woman who initially had back pain and pathologic vertebral compression fractures that were thought to be due to osteoporosis. Five months later, hypercalcemia developed and NSMM was diagnosed. No monoclonal gammopathy was found in the serum or urine, but skeletal survey showed diffuse osteolytic lesions, and bone marrow biopsy revealed marked plasmacytosis. The immunohistochemical techniques and chromosomal analysis methods that are currently available are discussed.

Advanced germ cell tumors in male patients

Germ cell tumors (GCTs) in male patients are particularly important in oncology because the impact of a cure in the young patient population is significant. Patients with poor-risk tumors by the international classification system have about a 50% likelihood of long-term survival. No randomized trial has proved a chemotherapy regimen to be superior to that of four courses of combination bleomycin, etoposide, and cisplatin. Ongoing research is evaluating the role of high-dose chemotherapy and hematopoietic stem cell transplantation as initial therapy in patients with intermediate-risk and poor-risk GCT. Newer agents such as gemcitabine and paclitaxel have shown promise and may be incorporated in future chemotherapeutic regimens. We review the major prognostication systems, areas of research directed at improving treatment outcome, and approaches that will improve understanding and management of these neoplasms in the future.

Empiric antimicrobial therapy of febrile neutropenic patients undergoing haematopoietic stem cell transplantation

This study was conducted to assess the efficacy and toxicity of intravenous (i.v.) ceftazidime and ciprofloxacin in neutropenic febrile patients undergoing high dose myeloablative therapy and hematopoietic stem cell transplantation (HSCT). All patients undergoing HSCT for leukaemia, lymphoma, multiple myeloma and solid tumours received open-label ceftazidime 2 g i.v. every 8 h and ciprofloxacin 400 mg i.v. every 12 h if they developed fever while they were neutropenic. Success with or without modification of this regimen was defined as survival through the neutropenic period; failure was defined as death secondary to infection. Of 106 patients treated with this regimen, the success rate was 99%. Sixty-one of the patients (57.5%) defervesced within 48-72 h and remained afebrile without regimen modification. In 41.5% of the cases (44/106), the regimen was modified because of persistent fever. One patient died secondary to sepsis. The combination of ceftazidime and ciprofloxacin as initial empiric antibacterial therapy in febrile neutropenic patients undergoing myeloablative therapy and HSCT is highly effective and is associated with minimal toxicity.

Ceftazidime and ciprofloxacin as empiric therapy in febrile neutropenic patients undergoing hematopoietic stem cell transplantation

This pilot study was done to assess the efficacy and toxicity of intravenous ceftazidime and ciprofloxacin in patients developing febrile neutropenia while undergoing high-dose myeloablative therapy and hematopoietic stem cell transplantation (HSCT). All patients undergoing high-dose chemoradiotherapy and HSCT for leukemias, lymphomas, multiple myeloma, and solid tumors received open-label ceftazidime 2 g intravenously every 8 hours and ciprofloxacin 400 mg intravenously every 12 hours if they developed fever while they were neutropenic. Success with or without modification of this regimen was defined as survival through the neutropenic period; failure was defined as death secondary to infection. Among 45 patients treated with this regimen, the success rate was 98%. Sixty-two percent (28 of 45) of the patients achieved defervescence within 48 to 72 hours and remained afebrile without regimen modification. In 16 patients (36%) the regimen was modified because of persistent fever. The combination of ceftazidime and ciprofloxacin as initial empiric antibacterial therapy in febrile neutropenic patients undergoing myeloablative therapy and HSCT appears to be highly effective and is associated with minimal toxicity.

The role of granulocyte colony-stimulating factor in hematopoietic stem cell transplantation

Recombinant granulocyte colony-stimulating factor (G-CSF) has been shown to decrease the duration of severe neutropenia, the incidence of febrile neutropenic episodes, the overall duration of intravenous antibiotic therapy, and the length of hospitalization in patients receiving myelosuppressive chemotherapy. G-CSF has also been shown to accelerate myeloid recovery after autologous and allogeneic bone marrow transplantation, and to mobilize stem cells in peripheral blood for hematopoietic rescue. However, the optimal dose, schedule, and method of administration of G-CSF in these settings remain to be standardized. This review focuses on the role of G-CSF in bone marrow and peripheral blood stem cell transplantation, and in hematopoietic stem cell mobilization.

The clinical applications of granulocyte colony-stimulating factor in hematopoietic stem cell transplantation: a review

The administration of recombinant human granulocyte colony-stimulating factor (G-CSF) following chemotherapy, has been shown, in controlled randomized trials, to decrease the incidence of febrile neutropenic episodes, the duration of severe neutropenia and intravenous antimicrobial therapy, and the length of hospitalization. This review focuses on the evolving role of G-CSF in bone marrow and peripheral blood stem cell transplantation, and in hematopoietic stem cell mobilization.

Allogeneic bone marrow transplantation

Allogeneic bone marrow transplantation (BMT) after high-dose, marrow-ablative chemoradiotherapy has been established as the treatment of choice for various hematologic, neoplastic, and congenital disorders. The most common type of marrow graft is an allogeneic one from a sibling donor who has compatible human leukocyte antigen (HLA). Only 30% of patients requiring allogeneic BMT have an HLA-compatible sibling donor. Over the past few years, marrows from unrelated HLA-compatible donors have been used with increasing frequency and promising outcome in certain hematologic malignancies. Despite the morbidity and mortality associated with this treatment modality, allogeneic BMT may provide a 20% to 90% chance of long-term, disease-free survival to patients with a wide variety of neoplastic and abnormal marrow disorders.

Allogeneic bone marrow transplantation: acute and late complications

Allogeneic bone marrow transplantation (BMT) following high-dose marrow-ablative chemoradiotherapy, has been established as the treatment of choice for various hematologic, neoplastic, and congenital disorders. This procedure is performed to restore lymphohematopoiesis in patients with bone marrow failure states, to replace a diseased marrow by a healthy donor marrow, and as "rescue" to reconstitute lymphohematopoiesis following marrow-ablative chemoradiotherapy to eradicate a malignancy. Only 30 percent of patients requiring marrow transplantation have an HLA-compatible sibling and very few patients have an identical twin donor (syngeneic graft). Over the past few years, marrows from unrelated HLA-compatible donors have been used with increasing frequency and promising outcome in certain hematologic malignancies. Infectious complications, graft-versus-host disease, veno-occlusive disease of the liver, leukemic relapse, and graft failure, remain major obstacles adversely affecting the outcome of patients undergoing allogeneic BMT. Despite these complications, allogeneic BMT remains a highly successful therapeutic procedure associated with a 20% to 90% long-term disease-free survival in a variety of patients.

Early drop in protein C and antithrombin III is a predictor for the development of venoocclusive disease in patients undergoing hematopoietic stem cell transplantation

Venoocclusive disease (VOD) of the liver remains one of the major obstacles for patients undergoing high-dose chemotherapy and hematopoietic stem cell transplantation (HSCT). Many factors have been associated with the development of VOD, including a hypercoagulable state secondary to a drop in protein C and antithrombin III (AT III). We conducted a prospective nonrandomized trial to try to determine whether the development of clinical VOD was associated with a drop in protein C, protein S, and AT III. A total of 42 patients undergoing high-dose chemotherapy and HSCT were enrolled in this study. Eleven patients underwent allogeneic bone marrow transplantation (BMT) following high-dose cyclophosphamide and fractionated total body irradiation (TBI). Thirty-one patients received autologous stem cell rescue following different preparative regimens. Measurements of protein C, protein S, and AT III levels were obtained prior to conditioning therapy and weekly thereafter for 2-3 weeks. A significant difference was noted in the mean levels of protein C on day 7 between those who developed VOD and those who did not (57.5 versus 72.1, p = 0.009). Similarly, there was a significant difference in the mean levels of AT III on days 7 and 14 between the two groups (day 7, 95.5 versus 80.6, p = 0.002; day 14, 99.6 versus 85.2, p = 0.01). The drop in protein S levels on days 7 and 14 was not statistically significant between the two groups. In conclusion, the degree of drop in protein C and AT III levels on day 7 was predictive for the development and severity of VOD.

Voltage-activated K+ conductance and cell proliferation in small-cell lung cancer

Whole-cell patch-clamp measurements indicate that human small-cell lung cancer (SCLC) cells express voltage-dependent potassium channels, whose function is blocked by K+ channel antagonist 4-aminopyridine (4-AP). Exposure of the tumour cells to 4 mM 4-AP reduced the peak outward K+ current (evoked by a depolarization to +80 mV) from 2.05 +/- 0.24 nA (mean +/- SEM, n = 28 cells) to 0.98 +/- 0.12 nA (n = 27). Incubation of SCL cells with 0.1, 4 and 16 mM 4-AP resulted in a concentration- and time-dependent reduction in the number of viable cells when compared with the control; over a period of 144 hours, the drug either significantly reduced the number of viable SCLC cells or caused an apparent cessation of neoplastic cell proliferation, whereas the untreated control cells demonstrated a more than 16-fold multiplication in the number of viable cells. The inhibitory effect on cell growth was also observed with an additional K+ channel antagonist, tetraethylammonium. These data suggest that voltage-activated K+ channels expressed by SCLC cells play a role in neoplastic cell proliferation.

Granulocyte colony-stimulating factor

Recombinant human granulocyte colony-stimulating factor (G-CSF) is a nonglycosylated protein produced in Escherichia coli using recombinant DNA technology. G-CSF was first defined in vitro as a relatively selective stimulator of pure granulocyte colonies from normal marrow and as a factor that induces differentiation of leukemic cell lines. Additional studies have shown that it has significant effects on primitive marrow stem cells as well as on the differentiated cells of the granulocyte-macrophage pathway enhancing phagocytosis, superoxide release, antibody-dependent cellular cytotoxicity, and migration of both neutrophils and monocytes. The most extensively studied clinical application of G-CSF has been in chemotherapy-induced myelosuppression, where it was shown to reduce the duration of severe neutropenia, the incidence of febrile neutropenic episodes, the overall duration of intravenous antibiotic therapy, and the length of hospitalization. G-CSF has also been shown to correct primary and acquired forms of neutropenia, to accelerate neutrophil recovery after bone marrow transplantation, and to mobilize stem cells in peripheral blood or hemopoietic rescue. G-CSF is well tolerated, mild to moderate bone pain being the most frequently reported adverse side effect. The clinical applications of G-CSF are likely to expand as more information emerges from continuing clinical trials.

Erythropoietin. Biology and clinical applications

Hemopoiesis is a complex process that underlies the production of highly specialized cells. The mechanisms involved in this process include positive and negative feedback by humoral activities, pluripotent stem cell self-renewal and differentiation, and local interactions between stromal components of the hemopoietic microenvironment and various stem and progenitor cells.

Peripheral hematopoietic stem cell transplantation: current concepts

As methods for increasing stem cells are perfected and alternate regimens for transplantation developed, PSCT will undoubtedly see wider application in combination with BMT and may ultimately replace BMT. The initial encouraging results with PSCT so far portend a major therapeutic role of this modality in the approach to hematologic and oncologic diseases. Prospective randomized trials comparing PSCT and BMT in a variety of clinical settings are needed and are already underway.

Hemolytic anemias. Diagnosis and management

Hemolysis can be induced by two general mechanisms. In the first one, erythrocytes lyse intravascularly due to complement fixation, trauma, or other extrinsic factors. In the second mechanism, which is the most common, the red cells are removed from the circulation by the mononuclear-phagocytic system either because they are intrinsically defective or because of the presence of bound immunoglobulins to their surfaces. The diagnosis of hemolysis is not difficult to establish and is based on the presence of anemia with sustained reticulocytosis in the absence of blood loss. Additional findings can include marrow erythroid hyperplasia; increased unconjugated bilirubin, LDH, and free hemoglobin; decreased haptoglobin and hemopexin; hemoglobinuria and hemosiderinuria; and decreased 51Cr red cell half-life. Hemoglobinemia, hemoglobinuria, and hemosiderinuria occur only in the setting of severe and rapid intravascular hemolysis. Conditions associated with significant lysis of red cells in the circulation include incompatible transfusion, G6PD deficiency, PNH, severe burns, and certain infections. The morphology of the red cell is abnormal in almost all cases of hemolytic anemia. However, the morphologic abnormality can be, in certain cases, diagnostic of the underlying condition. Treatment is usually supportive, with effective therapy directed to treat the underlying cause of hemolysis.

Small-cell carcinoma of the head and neck. A novel treatment regimen

Four patients with small-cell carcinoma (SCC) of the head and neck were treated in a pilot Phase I-II study to evaluate the response rate and toxicity of weekly non-cross-resistant combination chemotherapy administered as primary therapy in small-cell carcinomas. All four patients had locoregional disease without evidence of distant metastasis. The treatment regimen consisted of dose-intensive chemotherapy administered for 16 weeks. One or two of six cytotoxic agents (cisplatin, vincristine, methotrexate, Adriamycin, cyclophosphamide, and etoposide) were used weekly in different combinations followed by radiotherapy and/or surgical resection. To date, three of the four patients have completed therapy and achieved a complete response. The fourth patient is currently receiving chemotherapy and has achieved a partial response. Our treatment regimen appears effective in producing high initial response rates in SCC of the head and neck.

Hematopoietic growth factors

Hematopoiesis is a complex process that underlines the production of multiple highly specialized cells. The intricate mechanisms involved in this process include both positive and negative feedback by humoral activities, pluripotent stem cell selfrenewal and differentiation, and local interactions between stromal components of the hematopoietic microenvironment and various stem and progenitor cells. A group of hematopoietic growth factors, as well as their genes and chromosomal locations, have been identified. Advances in biochemistry and molecular biology led to the purification, genetic sequencing and molecular cloning of these glycoproteins. They include interleukin-3 (IL-3), granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF) and erythropoietin (EPO). The biologic specificity of these substances is defined by their ability to support proliferation and differentiation of hematopoietic cells in a semisolid clonal assay system. These factors share certain characteristics, including their ability to stimulate the function of mature cells, their overlapping activity affecting progenitor cells of several lineages, and their direct and indirect actions on nonhematopoietic cells. Trials using hematopoietic growth factors demonstrated their remarkable efficacy in a variety of clinical settings.

Spinal cord compression due to metastatic neoplasm

A retrospective study of 73 assessable patients with spinal cord compression due to metastatic tumor was conducted. Fifty-five patients had paraparesis and 18 were paraplegic. Treatment consisted of surgical decompression in 22 patients, radiotherapy in 31 patients, and a combination of both modalities in 20 patients. The three groups were comparable in their pretreatment characteristics. Of patients treated with surgical decompression followed by radiotherapy, 45% showed improvement in motor deficit; of patients treated with either surgery or radiotherapy, 18% (P = .06) and 16% (P = .02) showed improvement, respectively. These results were most significant in patients with paraparesis, where 47% of those who received combined therapy improved compared to 17% (P = .06) and 9% (P = .009) in the surgical and radiotherapy groups, respectively. In our series of patients with spinal cord compression due to metastatic tumor, surgical decompression followed by radiotherapy was superior to either surgical decompression or radiotherapy in improving motor deficit.

Treatment of small-cell carcinoma of the cervix with weekly combination chemotherapy

Three patients with small-cell carcinoma of the cervix entered a pilot study of combination chemotherapy with agents that are not cross-resistant. Two patients had local disease and the third had extensive metastatic disease of the liver. The regimen consisted of weekly chemotherapy for 16 weeks with cisplatin, vincristine, methotrexate, doxorubicin, cyclophosphamide and etoposide followed by radiotherapy and/or surgery. The two patients with local disease achieved a pathological complete response, with no evidence of disease at 24 months and 15 months from diagnosis. The third patient achieved a partial response and is alive at 13 months with progressive disease. Side-effects were tolerable.

Voltage-dependent ion channels in small-cell lung cancer cells

Small-cell carcinoma of the lung is a highly lethal form of cancer associated with a wide variety of paraneoplastic syndromes. Using the patch-clamp technique, we have directly demonstrated the presence of voltage-gated K+, Na+, and Ca2+ channels in three cell lines of human small-cell carcinoma, NCI-H128, NCI-H69, and NCI-H146. Whole-cell currents were measured from the tumor cells held at -80 mV and depolarized to -60 to +120 mV. Outward K+ current (IK), which was found in every cell tested, reached 1.58 +/- 0.12 nA (mean +/- SE, n = 24 cells) for H128 cells and 2.14 +/- 0.18 nA (n = 41) for H69 cells in response to a test potential of +80 mV. Unlike H69 and H128 tumor cells, IK from H146 cells occasionally exhibited partial inactivation during the 60-ms pulse length and reached 0.94 +/- 0.15 nA (n = 18) in response to a +80 mV test potential. IK from each of the cell lines was significantly reduced by 4-aminopyridine and tetraethylammonium. The rapidly inactivating inward Na+ current (INa), recorded in H146 cells and about 30% of the H69 and H128 cells tested, demonstrated a peak amplitude of 58 +/- 6 pA (n = 11) at 0 mV and a reversal potential of 47 +/- 2 mV (n = 11). Externally applied tetrodotoxin quickly suppressed INa. For the H128 and H69 tumor cells, inward Ca2+ current (ICa), observed in about 25% of the cells exposed to 10 mM [Ca2+]o, peaked at 5.1 +/- 0.4 ms (n = 5) with an amplitude of 46 +/- 14 pA (n = 5) at +20 mV and partially inactivated over the 40-ms depolarization. In H128 cells exposed to isotonic Ba2+ (110 mM), inward currents with time courses similar to those of ICa were recorded. Nearly all H146 tumor cells demonstrated a significant inward Ca2+ current which peaked with an amplitude of 93 +/- 16 pA (n = 26) at +30 to +40 mV in the presence of 10 mM [Ca2+]o. Application of test potentials 2 s in duration revealed that H146 ICa inactivated in a voltage-dependent manner with a time constant on the order of seconds. Adjustment of the holding potential from -80 mV to -40 mV had no observable effect on the amplitude of the evoked current. These voltage-dependent ion channels may have integral roles in several small-cell carcinoma bioelectric phenomena, including secretion, resting membrane potential, and action potential generation.(ABSTRACT TRUNCATED AT 400 WORDS)

High-dose chemotherapy and autologous marrow transplantation for esthesioneuroblastoma and sinonasal undifferentiated carcinoma

Eight patients with recurrent esthesioneuroblastoma or sinonasal undifferentiated carcinoma of the nasal or sinus cavities were treated with high-dose chemotherapy and autologous bone marrow transplantation. All patients had stage C disease initially and had received extensive prior conventional treatment with surgery, radiotherapy, and chemotherapy. Two patients achieved prolonged relapse-free survival for 18+ and 60 months. The latter patient relapsed at 60 months, but died of progressive disease after a second transplant. Two additional patients remain alive without disease progression at 17+ and 31+ months posttransplant. No deaths occurred secondary to toxicity. Progression of tumor accounted for failure in five patients. High-dose chemotherapy and autologous bone marrow transplantation should be considered as a salvage regimen for selected patients who fail conventional therapy for these diseases.

Treatment of small cell carcinoma with weekly combination chemotherapy. A pilot study

We conducted a prospective non-randomized pilot study to evaluate the response rate and toxicity of weekly combination chemotherapy in pulmonary and extrapulmonary small cell carcinoma. A consecutive collection of 13 patients seen at the University of Virginia Medical Center was entered into the study after written informed consent. Ten of these patients had small cell carcinoma of the lung (4 with limited disease and 6 with extensive disease) and 3 patients had extrapulmonary small cell carcinoma (esophagus, cervix, and larynx). The treatment regimen consisted of weekly chemotherapy for 16 weeks using six cytotoxic agents (cisplatin, vincristine, methotrexate, adriamycin, cyclophosphamide, and VP-16) in different combinations followed by radiotherapy to the primary site. To date, ten patients have completed chemotherapy and radiotherapy with 9 (90%) achieving a complete response. The overall objective response rate was 100%. Of the remaining 3 patients who are currently receiving treatment, one achieved a complete response and two are showing significant responses. This ongoing trial shows that a weekly combination chemotherapy regimen is effective in producing high response rates in small cell carcinoma.