Long-term Effectiveness of Integrated Caries Preventive Programs in Thailand Among Preschool Children Using a System Dynamics Model

OBJECTIVE

To compare the effect of three caries preventive interventions provided by Thailand's Ministry of Public Health (MOPH): supervised toothbrushing (STB), fluoride varnish (FV), and combined STB+FV from 0 to 5 years old to the base case using the System Dynamics Model (SDM).

METHODS

The SDM was developed to compare the intervention scenarios: STB, FV, and combined STB+FV with the base case scenario. Meta-analyses determined the effective rates of the interventions included in the model.

RESULTS

The model indicated that the population with no caries in deciduous teeth increased by 7.5%, 5.7%, and 4.2% at three years of age, and 12.8%, 9.9%, and 5.9% at five years of age, under STB+FV, STB, and FV respectively when compared to the base case. At three years old, the population with untreated caries in deciduous teeth decreased by 12.9% in STB+FV, 9.8% in STB, and 7.3% in FV, and by 10.9% in STB+FV, 8.5% in STB, and 4.9% in FV, at five years old. The increase in the population without caries is considered clinically significant compared to baseline.

CONCLUSION

The model determined that an effective combination of STB and FV should be administered between 0 and 5 years of age to reduce caries in the primary dentition. The SDM could be applied as a "what-if" analysis in order to determine the most beneficial intervention or policy by comparing them.

Management and Outcomes of Hematological Immune-related Adverse Events: Systematic Review and Meta-analysis

Data regarding clinical outcomes and management of hematological manifestations of immune checkpoint inhibition (ICI) is limited to case reports, series, and a few retrospective reviews. We aimed to determine the rate of response of hematological immune-related adverse events (irAEs) to immunosuppressive therapy. MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to the present day. Retrospective reports were included without language restrictions. The risk of bias was evaluated with the Cochrane Collaboration's tool. The primary outcome of this study was the rate of response to immunosuppression. Eighty studies (14 case series and 66 individual case reports) were analyzed with a total of 135 patients with ICI-related hematological irAEs. Data analysis showed an average proportional response rate to immunosuppression among hematological irAE entities of 50% (range: 25%-70%). The heterogeneity index (I2) was 0% among reports within each entity. There is a wide spectrum of hematological manifestations to ICI therapy, and to date there is no large randomized-controlled trial data to evaluate the efficacy of treatment strategies for hematological irAEs. We found a variable overall response rate to immunosuppression therapy of around 50%, without statistically significant heterogeneity among different irAE types but significant differences among the different countries of publication. Future studies evaluating the optimal dose and duration of immunosuppressive agents for patients with hematological irAEs should be undertaken.

Treatment of catheter-related thrombosis in patients with hematologic malignancies: A Venous thromboEmbolism Network U.S. retrospective cohort study

INTRODUCTION

Optimal treatment of catheter-related thrombosis (CRT) is uncertain in patients with hematologic malignancy. We aimed to evaluate the treatment strategies, outcomes, and predictors of recurrent venous thromboembolism (VTE) associated with catheter-related thrombosis (CRT) in patients with hematologic malignancy.

METHODS

We performed a multicenter retrospective cohort study of eight institutions through the Venous thromboEmbolism Network US. Patients with hematologic malignancies with documented CRT were identified using ICD-9 and ICD-10 diagnostic codes. Semi-competing risks proportional hazard regression models were created.

RESULTS AND CONCLUSIONS

Of the 663 patients in the cohort, 124 (19%) were treated with anticoagulation alone, 388 (58%) were treated with anticoagulation and catheter removal, 119 (18%) treated with catheter removal only, and 32 (5%) had neither catheter removal nor anticoagulation. 100 (15%) patients experienced a recurrent VTE event. In the 579 patients who had catheter removal, the most common reason for catheter removal was the CRT [392 (68%)]. For subjects who received any anticoagulation (n = 512), total anticoagulation duration was not associated with VTE recurrence [1.000 (0.999-1.002)]. After adjustment patients treated with catheter removal only had an increased risk of VTE recurrence [2.50 (1.24-5.07)] and death [4.96 (2.47-9.97)]. Patients with no treatment had increased risk of death [16.81 (6.22-45.38)] and death after VTE recurrence [27.29 (3.13-238.13)]. In this large, multicenter retrospective cohort, we found significant variability in the treatment of CRT in patients with hematologic malignancy. Treatment without anticoagulation was associated with recurrent VTE.

Clinical and laboratory features of autoimmune hemolytic anemia associated with immune checkpoint inhibitors

Immune checkpoint inhibitors (ICPis) are a novel class of immunotherapeutic agents that have revolutionized the treatment of cancer; however, these drugs can also cause a unique spectrum of autoimmune toxicity. Autoimmune hemolytic anemia (AIHA) is a rare, but often severe, complication of ICPis. We identified 14 patients from nine institutions across the United States who developed ICPi-AIHA. The median interval from ICPi initiation to development of AIHA was 55 days (interquartile range [IQR], 22-110 days). Results from the direct antiglobulin test (DAT) were available for 13 of 14 patients: 8 patients (62%) had a positive DAT and 5 (38%) had a negative DAT. The median pretreatment and nadir hemoglobin concentrations were 11.8 g/dL (IQR, 10.2-12.9 g/dL) and 6.3 g/dL (IQR, 6.1-8.0 g/dL), respectively. Four patients (29%) had a preexisting lymphoproliferative disorder, and two (14%) had a positive DAT prior to initiation of ICPi therapy. All patients were treated with glucocorticoids, with three requiring additional immunosuppressive therapy. Complete and partial recoveries of hemoglobin were achieved in 12 (86%) and 2 (14%) patients, respectively. Seven patients (50%) were rechallenged with ICPis, and one (14%) developed recurrent AIHA. Clinical and laboratory features of ICPi-AIHA were similar in DAT positive and negative patients. ICPi-AIHA shares many clinical features with primary AIHA; however, a unique aspect of ICPi-AIHA is a high incidence of DAT negativity. Glucocorticoids are an effective first-line treatment in the majority of patients with ICPi-AIHA, and most patients who are rechallenged with an ICPi do not appear to develop recurrence of AIHA.

Abstract P1-16-04: Risk of venous thromboembolism with abemaciclib based regimen versus other CDK 4/6 inhibitor containing regimens in patients with hormone receptor-positive HER2-negative metastatic breast cancer

Background: Approximately 70% of patients with metastatic breast cancer (MBC) are hormone receptor (HR) - positive and the cyclin dependent kinases (CDK) along with their D-type cyclin catalysts, have been shown to play a role in mediating the resistance to endocrine therapy. Several CDK-targeted agents have been recently approved by FDA. Nevertheless, the risk of venous thromboembolism (VTE) with the use of different CDK 4/6 inhibitors has never been reported. We undertook a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of VTE with abemaciclib based regimens versus other CDK 4/6 inhibitor containing regimens in patients with HR-positive HER2-negative MBC.

Methods: We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through February 2018. The randomized controlled trials that mention deep vein thrombosis and pulmonary embolism as adverse effects of CDK 4/6 inhibitor therapy were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR) and risk difference (RD) with 95% confidence interval (CI).

Results: Five phase 3 studies and one phase 2 study with a total of 3,159 patients with HR-positive HER2-negative MBC were eligible for analysis. The study arms used palbociclib-letrozole, palbociclib-fulvestrant, ribociclib-letrozole, abemaciclib-fulvestrant, and abemaciclib-nonsteroidal aromatase inhibitors (either letrozole or anastrozole) while the control arms utilized placebo in combination with letrozole or anastrozole or fulvestrant. The randomization ratio was 2 to 1 in PALOMA-2, PALOMA-3, MONARCH-2 and MONARCH-3 studies and 1 to 1 in PALOMA-1 and MONALEESA-2 trials. CDK 4/6 inhibitors were utilized as first line treatment in PALOMA-1, PALOMA-2, MONALEESA-2 and MONARCH-3. The I2 statistic for heterogeneity was 0, and the heterogeneity X2 (Cochran's Q) was 1 (P= 0.707), suggesting homogeneity among RCTs. The VTE incidence was 25 (3.255%) in the abemaciclib group vs 2 (0.520%) in the control group. The pooled relative risk for VTE was 6.222 (95% CI: 1.481 – 26.145, P = 0.013) and the absolute RD was 0.027 (95% CI: 0.013 – 0.042, P < 0.0001). In other CDK 4/6 inhibitor containing regimens, the VTE incidence was reported at 15 (1.243%) vs 2 (0.374%) in the control arm. The pooled RR for VTE was 2.312 (95% CI: 0.852 –6.272, P = 0.100) and the absolute RD was 0.008 (95% CI: - 0.000 – 0.017, P = 0.259).

Conclusion: VTE is a major cause of morbidity and mortality and is particularly common in patients with breast cancer. Our meta-analysis demonstrated that the addition of abemaciclib to endocrine therapy notably contributed to a higher incidence of VTE with a relative risk of 6.22. However, no significant increase in the risk of VTE was noted in other CDK 4/6 inhibitor-based regimen. More randomized trials are required to determine the actual relation and definitive incidence of VTE among different CDK-targeted agents when added to endocrine therapy.

Citation Format: Thein KZ, Ball S, Zaw MH, Quirch M, Hardwicke F, Awasthi S, Oo TH, Jones C. Risk of venous thromboembolism with abemaciclib based regimen versus other CDK 4/6 inhibitor containing regimens in patients with hormone receptor-positive HER2-negative metastatic breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-16-04.

Copper deficiency anemia: review article

Copper is a crucial micronutrient needed by animals and humans for proper organ function and metabolic processes such as hemoglobin synthesis, as a neurotransmitter, for iron oxidation, cellular respiration, and antioxidant defense peptide amidation, and in the formation of pigments and connective tissue. Multiple factors, either hereditary or acquired, contribute to the increase in copper deficiency seen clinically over the past decades. The uptake of dietary copper into intestinal cells is via the Ctr1 transporter, located at the apical membrane aspect of intestinal cells and in most tissues. Copper is excreted from enterocytes into the blood via the Cu-ATPase, ATP7A, by trafficking the transporter towards the basolateral membrane. Zinc is another important micronutrient in animals and humans. Although zinc absorption may occur by direct interaction with the Ctr1 transporter, its absorption is slightly different. Copper deficiency affects physiologic systems such as bone marrow hematopoiesis, optic nerve function, and the nervous system in general. Detailed pathophysiology and its related diseases are explained in this manuscript. Diagnosis is made by measuring serum copper, serum ceruloplasmin, and 24-h urine copper levels. Copper deficiency anemia is treated with oral or intravenous copper replacement in the form of copper gluconate, copper sulfate, or copper chloride. Hematological manifestations are fully reversible with copper supplementation over a 4- to 12-week period. However, neurological manifestations are only partially reversible with copper supplementation.

Abstract P3-14-02: Incidence of venous thromboembolism in patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with CDK 4/6 inhibitors: A systematic review and meta- analysis of randomized controlled trials

Background:

The cyclin dependent kinases (CDK) along with their partners, the cyclins, have a crucial role in regulation of the cell cycle. Several CDK-targeted agents have been employed in hormone receptor positive metastatic breast cancer (MBC) with noteworthy safety concerns. Nevertheless, the impact of this agent on risk of venous thromboembolism (VTE) remains uncertain. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of VTE among patients with hormone receptor-positive HER2-negative MBC treated with CDK 4/6 inhibitors.

Methods:

We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through June 2017. Trials that mention deep vein thrombosis and pulmonary embolism as adverse effects were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% confidence interval (CI). Pooled VTE rates were estimated as follows: we multiplied the median follow-up duration by the sample size. Crude study-specific VTE rates were then calculated by dividing the number of incident VTE cases by the total number of person-months follow-up.

Results:

A total of 2671 patients with hormone receptor-positive HER2-negative MBC from four phase 3 studies and one phase 2 study were eligible for analysis. The study arm used palbociclib-letrozole, palbociclib-fulvestrant, ribociclib-letrozole and abemaciclib-fulvestrant while the control arm utilized placebo in combination with letrozole or fulvestrant. The I2 statistic for heterogeneity was 13.6, and the heterogeneity X2 (Cochran's Q) was 4.6 (P= 0.3), suggesting homogeneity of results among the randomized trials. The VTE incidence was 24 (1.46%) in CDK 4/6 group vs 4 (0.39%) in control group. The pooled RR for VTE was 2.736 (95% CI: 1.115 – 6.714, P = 0.028) and the absolute RD was 0.010 (95% CI: 0.002 – 0.018, P = 0.010) according to the fixed effects model. By the random effects model, the pooled RR was 2.411 (95% CI: 0.809 – 7.181, P = 0.114) and RD was 0.009 (95% CI: 0.0 – 0.019, P = 0.048). Over median follow up of 36 months, the RR for VTE was 3.792 (95% CI: 1.838 – 7.822, P < 0.0001) and RD was 0.024 (95% CI: 0.014 – 0.034, P < 0.0001) with the fixed effects model. By the random effects model, the pooled RR for VTE was 4.248 (95% CI: 0.952- 18.959, P = 0.058) and RD was 0.026 (95% CI: 0.004 – 0.021, P < 0.0001). The pooled rate of VTE among CDK 4/6 group was 2.99 per person years compared to 0.50 per person years among control arm.

Conclusion:

Approximately 1% of patients on letrozole or fulvestrant alone developed VTE in previous studies. Our meta-analysis demonstrated that the addition of CDK 4/6 inhibitors to letrozole or fulvestrant, contribute to higher incidence of VTE. More randomized trials are required to determine the actual relation and definitive incidence of VTE, a major cause of morbidity and mortality among these patients.

Citation Format: Thein KZ, Zaw MH, Tun AM, Jones C, Radhi S, Hardwicke F, Oo TH. Incidence of venous thromboembolism in patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with CDK 4/6 inhibitors: A systematic review and meta- analysis of randomized controlled trials [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-14-02.

Acquired amegakaryocytic thrombocytopenia and red cell aplasia in a patient with thymoma progressing to aplastic anemia successfully treated with allogenic stem cell transplantation

Association of pure red-cell aplasia with thymoma is well documented. However, acquired amegakaryocytic thrombocytopenia (AAMT) has been rarely associated with thymoma with only five reported cases in literature. We report a patient with thymoma complicated by pure red cell aplasia (PRCA) and AAMT who progressed to develop aplastic anemia (AA). The patient was refractory to 10-months of immunosuppressive therapy with cyclosporine, prednisone, and antithymocyte globulin. She was eventually treated with allogeneic stem cell transplantation (allo-SCT). On Day +323 the patient continues to be transfusion-independent. This case illustrates how in patients with thymoma and AAMT may herald development of AA. This is also the first report of a patient with AAMT progressing to thymoma-associated AA being successfully treated with allo-SCT. The successful outcome suggests allo-SCT as a feasible option similar to other AA patients.

Frequency of venous thromboembolism events during acute inpatient rehabilitation in a comprehensive cancer centre

OBJECTIVE

To determine the frequency of venous thromboembolism, possible predictors, and the association between venous thromboembolism and Functional Independence Measure (FIM) scores and length of stay among cancer patients admitted to the inpatient rehabilitation unit at a cancer centre.

DESIGN

Retrospective analysis of patients admitted to acute inpatient rehabilitation from September 2011 to June 2013. Subject/patients: Cancer patients in the acute inpatient rehabilitation unit within a tertiary cancer centre.

METHODS

International Classification of Diseases (ICD-9) codes identified deep vein thrombosis, pulmonary embolism, and inferior vena cava filter.

RESULTS

Venous thromboembolism occurred in 32/611 patients (5.2%): 23/611 (3.8%) during the course of hospitalization before admission to rehabilitation, and 9/611 patients (1.5%) during rehabilitation. Patients with lower extremity oedema at admission (p = 0.0218) had a higher chance of subsequently developing venous thromboembolism. Patients with venous thromboembolism during rehabilitation had a significantly lower FIM transfer score at admission to rehabilitation (p = 0.0247), a longer length of stay in rehabilitation (p = 0.0013) and overall hospitalization (p = 0.0580).

CONCLUSION

Cancer patients with low FIM transfer scores and lower extremity oedema are at higher risk of venous thromboembolism. Patients with these clinical findings at admission may require measures for more aggressive surveillance for the presence of venous thromboembolism. Patients with venous thromboembolism had an increased length of stay in rehabilitation, but ultimately did not have significant differences in FIM score changes.

Successful treatment of aplastic anemia-paroxysmal nocturnal hemoglobinuria associated with eosinophilic fasciitis with matched unrelated donor allogeneic peripheral blood stem cell transplantation

We report the first patient case of successful treatment intervention for both eosinophilic fasciitis and aplastic anemia with allogeneic peripheral blood stem cell transplantation from a matched unrelated donor after multiple immunosuppressant failure.

Vitamin B12 deficiency--A 21st century perspective

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JAK2 (V617F) Positive Latent Myeloproliferative Neoplasm Presenting with Splanchnic Vein Thrombosis

Myeloproliferative neoplasms (MPNs) are chronic clonal hematopoietic stem cell disorders characterized by proliferation of one or more of the granulocytic, red cell or platelet lineages in the bone marrow, with fairly normal maturation, resulting in increase in the leukocyte, erythrocytes and platelets in the blood. They also represent a common cause of splanchnic vein thrombosis (SVT). Herein, we describe a case of SVT as a presenting symptom of latent MPN. The patient has had normal complete blood counts since presentation. 3 ½ years later, she was found to have JAK2 (V617F) mutation and bone marrow biopsy was consistent with MPN. Five years later, her platelet count started to rise. In patients with a first episode of SVT, thrombophilia workup including JAK2 (V617F) mutation is warranted. Anticoagulation with heparin and warfarin is the treatment of choice for SVT.

Coadministration of telaprevir and transcatheter arterial chemoembolization in hepatitis C virus-associated hepatocellular carcinoma

The use of direct-acting antiviral agents (e.g., telaprevir, boceprevir) has improved response rates in patients with hepatitis C virus (HCV) genotype 1 infections. Substantial number of drug-drug interactions are anticipated with the use of telaprevir, a cytochrome P450 3A and P-glycoprotein substrate and inhibitor. Herein we describe a patient with HCV-associated hepatocellular carcinoma treated simultaneously with a telaprevir-containing regimen and localized chemotherapy (transcatheter arterial chemoembolization) with doxorubicin. No clinically relevant interactions or adverse events developed while on antiviral therapy.

Sequencing of t(2;7) translocations reveals a consistent breakpoint linking CDK6 to the IGK locus in indolent B-cell neoplasia

The translocation t(2;7)(p11;q21) has repeatedly been documented in association with indolent B-cell lymphoproliferative disorders (BLPDs). However, the chromosomal breakpoints associated with this recurrent translocation have rarely been characterized. Using an approach based on long-range PCR, we mapped the t(2;7) breakpoints in five patients presenting with indolent B-cell neoplasia. The sequencing of these rearrangements revealed several striking parallels across the t(2;7) breakpoints. The junction sites on 2p11 consistently mapped to the heptamer recombination signal sequence (RSS) of an immunoglobulin kappa variable gene (IGK) within the Vκ3 family, while the breakpoints on 7q21 each localized to within 4 bp of an RSS-like element located approximately 0.5 kb upstream of the transcription start site of the cyclin-dependent kinase 6 gene (CDK6). These findings confirm the significant genetic overlap arising in BLPD-associated t(2;7) translocations, and implicate the deregulated expression of CDK6 as a common molecular mechanism involved in the emergence of clonal B-cell proliferations presenting with this recurrent abnormality. In addition, the successful mapping of the t(2;7) translocations in each of five patients using a simple PCR-based protocol highlights the potential diagnostic utility of this approach during characterization of cases harboring analogous rearrangements.

Amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation

Amniotic fluid embolism is a rare syndrome with potentially lethal outcomes. Complications include cardiorespiratory failure, disseminated intra-vascular coagulation, seizures, neurological deficits, and death. A 34-year-old woman had amniotic fluid embolism complicated by paradoxical embolism and disseminated intravascular coagulation. Emergency cesarean section followed by cardiopulmonary bypass with removal of the clot from the atria and closure of the patent foramen ovale was performed, resulting in a good outcome for both the mother and the baby. Subsequent treatment with anticoagulants for 6 months was recommended. A literature review revealed that this clinical scenario is rare but can be successfully managed by cardiopulmonary bypass and thromboembolectomy. Data on guidelines for the use of anticoagulation in this situation are limited.

Amiodarone-Associated Bone Marrow Granulomas: A Report of 2 Cases and Review of the Literature

Amiodarone therapy is associated with several adverse effects, including hematologic ones such as pancytopenia, hemolytic anemia, and aplastic anemia. Very few cases of amiodarone-associated bone marrow granulomas have been reported. We report 2 cases of amiodarone-associated bone marrow granulomas. Patient 1 was an 81-year-old man who presented with leukopenia, thrombocytopenia, and hepatosplenomegaly after 2 years of amiodarone therapy. Patient 2 was an 80-year-old man who presented with pancytopenia 2 1/2 years after starting amiodarone treatment. Both patients had normal blood counts before amiodarone therapy. Bone marrow biopsies showed noncaseating granulomas in both patients. We reviewed the literature available on Medline for amiodarone-associated bone marrow granulomas and found 8 reported cases of amiodarone-associated bone marrow granulomas. One case also featured amiodarone-associated hepatic granulomas. Amiodarone therapy was stopped in 5 cases, with improvement of the granulomas occurring in 3 cases. We conclude that bone marrow granulomas, although rare, should be considered as a differential diagnosis for patients undergoing amiodarone therapy and presenting with cytopenias.

Gastric relapse of solitary bone plasmacytoma

This case report describes a patient with solitary bone plasmacytoma who had a gastric relapse of his tumor. Skeletal surveys, magnetic resonance imaging of the spine, and bone marrow examination done at the time of relapse failed to show any other site of disease. Positron emission tomography finally clarified the true extent of the tumor.

Drug Insight: new antiemetics in the management of chemotherapy-induced nausea and vomiting

Nausea and vomiting remain among the most feared side effects of chemotherapy for cancer patients. Significant progress has been made in the last 15 years in developing more effective and better-tolerated measures to minimize chemotherapy-induced nausea and vomiting (CINV). During the 1990s, the selective 5-hydroxytryptamine receptor antagonists were first introduced for the treatment of CINV, and resulted in more effective and better tolerated treatment of CINV. Despite recent progress, however, a significant number of patients still develop CINV, particularly during the 2-5 day period (delayed emesis) following chemotherapy. There is evidence that this may be an underappreciated problem on the part of some caregivers. Recently, two new antiemetics, aprepitant, the first member of the neurokinin-1 antagonists, and palonosetron, a second-generation 5-hydroxytryptamine receptor antagonist, received regulatory approval in the US. Both represent useful additions to the therapeutic armamentarium for the management of CINV.

A Co-ligand Complex Anchors Plasmodium falciparum Merozoites to the Erythrocyte Invasion Receptor Band 3

In Plasmodium falciparum malaria, erythrocyte invasion by circulating merozoites may occur via two distinct pathways involving either a sialic acid-dependent or -independent mechanism. Earlier, we identified two nonglycosylated exofacial regions of erythrocyte band 3 termed 5ABC and 6A as an important host receptor in the sialic acid-independent invasion pathway. 5ABC, a major segment of this receptor, interacts with the 42-kDa processing product of merozoite surface protein 1 (MSP1(42)) through its 19-kDa C-terminal domain. Here, we show that two regions of merozoite surface protein 9 (MSP9), also known as acidic basic repeat antigen, interact directly with 5ABC during erythrocyte invasion by P. falciparum. Native MSP9 as well as recombinant polypeptides derived from two regions of MSP9 (MSP9/Delta1 and MSP9/Delta2) interacted with both 5ABC and intact erythrocytes. Soluble 5ABC added to the assay mixture drastically diminished the binding of MSP9 to erythrocytes. Recombinant MSP9/Delta1 and MSP9/Delta2 present in the culture medium blocked P. falciparum reinvasion into erythrocytes in vitro. Native MSP9 and MSP1(42), the two ligands binding to the 5ABC receptor, existed as a stable complex. Our results establish a novel concept wherein the merozoite exploits a specific complex of co-ligands on its surface to target a single erythrocyte receptor during invasion. This new paradigm poses a new challenge in the development of a vaccine for blood stage malaria.

Adrenal hemorrhage secondary to metastasis from lung cancer

The adrenals are common metastatic sites for lung cancers as well as a number of other primary cancers. Usually these metastases are asymptomatic. Hemorrhagic adrenal metastases from lung cancer are extremely rare. Only 5 prior reports of hemorrhagic adrenal metastases from lung cancer have appeared in the English literature. We report a case of spontaneous, massive, adrenal hemorrhage secondary to metastatic lung cancer in a 62-year-old patient. In lung cancer, patients with sudden onset of pain in the flank or back in association with anemia and hypotension, adrenal hemorrhage secondary to metastatic disease should be considered in the differential diagnosis. Computed tomography scans and magnetic resonance imaging aid in confirming the diagnosis.

Unfavorable Therapeutic Index of Cisplatin/Gemcitabine/Vinorelbine in Advanced non—small-Cell Lung Cancer

In view of favorable reports with the 3-drug combination of PGV (cisplatin/gemcitabine/vinorelbine), this multicenter phase II study evaluated the therapeutic index of PGV in patients with advanced non-small-cell lung cancer (NSCLC). Thirty-two patients with stage IV NSCLC and 1 with stage IIIB were studied. There were 23 men and 10 women, with a median age of 63 years (range, 38-80 years). Twelve patients had a performance status (PS) of 0, and 21 patients had a PS of 1. Treatment consisted of cisplatin 50 mg/m2, gemcitabine 1000 mg/m2, and vinorelbine 25 mg/m2 all given intravenously on days 1 and 8, in 21-day cycles. Fifteen patients (45%; 95% confidence interval (CI), 28%-64%) achieved a partial response. Median response duration was 3 months (range, 1-9 months). The median and 1-year survival rates were 9.4 months and 39% (95% CI, 23%-58%), respectively. The median number of cycles was 4. Only 3 patients (9%) completed treatment without regimen modifications. Median dose intensity (% planned) was cisplatin 24 mg/m2/week (72%), gemcitabine 483 mg/m2/week (72%), and vinorelbine 12 mg/m2/week (72%). Toxicities were predominantly hematologic, with grade 3/4 neutropenia (67%), febrile neutropenia (21%), and thrombocytopenia (67%). There were 3 (9%) treatment-related deaths due to neutropenic complications. This study confirms the substantial antineoplastic activity of PGV. We observed a high rate of severe hematologic toxicity, especially febrile neutropenia, despite a lower delivered dose intensity of PGV. Given these results, PGV appears to offer no therapeutic advantage to current doublet regimens.