Height-based formulas for predicting intravascular length of tunnelled neck central venous catheter in paediatric population

INTRODUCTION

Central venous catheter (CVC) placement is commonly performed in children. We aim to develop simple formulas to predict CVC intravascular length to minimise radiation exposure associated with the procedure.

METHODS

124 paediatric patients who received tunnelled neck CVCs and subsequent CT thorax at Hong Kong Children's Hospital from January 2020 to July 2022 were reviewed retrospectively. Formula development cohorts were subdivided by insertion sites-9 right external jugular vein (REJV), 41 right internal jugular vein (RIJV), 14 left external jugular vein (LEJV), 10 left internal jugular vein (LIJV). Using measurements from CT by two radiologists, formulas predicting the CVC intravascular length based on height and insertion sites were developed using a linear regression model. These formulas were tested with validation cohorts (10 randomly selected cases in REJV and RIJV groups respectively). Validation cohorts were not available for LEJV and LIJV groups due to small sample sizes.

RESULT

The goodness-of-fit (R^2) of all formulas are above 0.8. In the validation cohorts, the REJV formula was predictive of intravascular CVC length within 1 cm in 70% of CVC with mean absolute difference of 0.63 cm (SD 0.48 cm), and the RIJV formula was predictive of intravascular CVC length within 1 cm in 80% of CVC with mean absolute difference of 0.67 cm (SD 0.53 cm).

CONCLUSION

Intravascular CVC length can be estimated using simple formulas based on height and insertion sites. Further prospective validation of the LEJV and LIJV formulas is needed.

Workforce Capacity and Capability Building Through Metrics-Based Mentoring Partnerships

Background: Globally, cancer is the second leading cause of death. Low- and middle-income countries (LMICs) especially lack the sufficient healthcare and oncology workforces needed to screen, diagnose and treat individuals with cancer. While traditional academic and training programs designed to produce healthcare professionals in these countries fill a critical role, few programs exist that maintain, develop, and increase the knowledge, skills, and professional performance of current healthcare and oncology workforces. Mentoring partnerships and twinning programs can provide ongoing education and training that strengthen and build workforce capacity and capability for the full scope of cancer care. Aim: The goal is to achieve resource-appropriate multimodality cancer-care using guideline- and protocol-based education and training and also to develop the capability to conduct world quality research. The model utilizes in-person, in-country site visits lasting from several weeks to months and ongoing connectivity through weekly telemedicine video conferences. Methods: The International Cancer Expert Corps (ICEC) and partner organizations are establishing a network of global and multisectoral partnerships that builds human capacity and capability needed to establish sustainable cancer programs that function at world-class standards. The three-fold mentor-mentee approach ( www.iceccancer.org ) is built by 1) enlisting hubs of expertise to include academic medical centers/universities, private practices and an ICEC Central Hub, 2) enrolling the breadth of expert-mentors needed from a university, practice, professional society and interested individuals, and 3) identifying centers in LMICs - clinics/hospitals/and other care delivery sites in underserved areas, and associates - physicians/allied healthcare workers- seeking mentoring and education. Results: Recent implementation of the ICEC 5-Step Progression Plan provides guidance and serves as an assessment tool for measuring progress between the hubs-centers programs and expert-associate. Twinning programs (hubs-ICEC centers) have been established in multiple sites worldwide including in Africa, Asia and Eurasia. Conclusion: Implementation of the ICEC 5-Step Progression Plan provides a platform from which to track the current stages and progress of twinning mentor-mentee programs, and to evaluate new programs. This information guides the programs and also provides metric-based investment in global health. Critically as the skills in associates and ICEC centers grows, they achieve expert-mentor status and centers become hubs to serve the surrounding regions, thereby enabling geometric growth in cancer care to meet the needs of the growing global burden of cancer. The content is the personal opinion of the authors and not their organizations.

Early post transplant (F-18) 2-fluoro-2-deoxyglucose positron emission tomography does not predict outcome for patients undergoing auto-SCT in non-Hodgkin and Hodgkin lymphoma

Positron emission tomography (PET) in conjunction with computed tomography is a frequently used modality for staging patients with lymphoma. Utility of PET-computed tomography before or early following auto-SCT has not been as rigorously evaluated. We retrospectively analyzed patients who received auto-SCT for treatment of relapsed or refractory non-Hodgkins lymphoma or Hodgkins disease between the years of 1996 and 2007. Patients who had either a PET scan following salvage chemotherapy within 14 weeks of transplantation (pre-PET), and/or a PET scan 6-14 weeks following transplantation (post-PET) were included. A total of 90 patients were identified for analysis. The median follow-up time is 3.3 years, with a range of 0.13-12.0 years. The median PFS was 4.6 years, and median OS was 5.1 years. At the time of this analysis, 34 patients (37%) experienced disease relapse, and 25 (27%) of the patients died from disease progression. In multivariate Cox proportional hazards analysis, post-PET did not predict for outcome, pre-PET positivity predicted for decrease in PFS. In conclusion, post-PET scan did not predict for PFS or OS in multivariate analysis. Positive pre-PET scan did predict for PFS as seen in previous studies, and may help identify patients who would benefit from innovative post transplant therapies.

Regulating regulatory T cells

Regulatory T cells (Tregs) are a specialized subpopulation of T cells that act to suppress activation of other immune cells and thereby maintain immune system homeostasis, self-tolerance as well as control excessive response to foreign antigens. The mere concept of Tregs was the subject of significant controversy among immunologists for many years owing to the paucity of reliable markers for defining these cells and the ambiguity of the nature and molecular basis of suppressive phenomena. However, recent advances in the molecular characterization of this cell population have firmly established their existence and their vital role in the vertebrate immune system. Of interest, accumulating evidence from both humans and experimental animal models has implicated the involvement of Tregs in the development of graft-versus-host disease (GVHD). The demonstration that Tregs could separate GVHD from graft-versus-tumor (GVT) activity suggests that their immunosuppressive potential could be manipulated to reduce GVHD without detrimental consequence on GVT effect. Although a variety of T lymphocytes with suppressive capabilities have been reported, the two best-characterized subsets are the naturally arising, intrathymic-generated Tregs (natural Tregs) and the peripherally generated, inducible Tregs (inducible Tregs). This review summarizes our current knowledge of the generation, function and regulation of these two populations of Tregs during an immune response. Their role in the development of GVHD and their therapeutic potential for the prevention and treatment of GVHD will also be described.

Pharmacokinetic and maximum tolerated dose study of micafungin in combination with fluconazole versus fluconazole alone for prophylaxis of fungal infections in adult patients undergoing a bone marrow or peripheral stem cell transplant

In this dose escalation study, 74 adult cancer patients undergoing bone marrow or peripheral blood stem cell transplantation received fluconazole (400 mg/day) and either normal saline (control) (12 subjects) or micafungin (12.5 to 200 mg/day) (62 subjects) for up to 4 weeks. The maximum tolerated dose (MTD) of micafungin was not reached, based on the development of Southwest Oncology Group criteria for grade 3 toxicity; drug-related toxicities were rare. Commonly occurring adverse events considered related to micafungin were headache (6.8%), arthralgia (6.8%), hypophosphatemia (4.1%), insomnia (4.1%), maculopapular rash (4.1%), and rash (4.1%). Pharmacokinetic profiles for micafungin on days 1 and 7 were similar. The mean half-life was approximately 13 h, with little variance after repeated or increasing doses. Mean maximum concentrations of the drug in serum and areas under the concentration-time curve from 0 to 24 h were approximately proportional to dose. There was no clinical or kinetic evidence of interaction between micafungin and fluconazole. Five of 12 patients (42%) in the control group and 14 of 62 (23%) in the micafungin-plus-fluconazole groups had a suspected fungal infection during treatment which resulted in empirical treatment with amphotericin B. The combination of micafungin and fluconazole was found to be safe in this high-risk patient population. The MTD of micafungin was not reached even at doses up to 200 mg/day for 4 weeks. The pharmacokinetic profile of micafungin in adult cancer patients with blood or marrow transplants is consistent with the profile in healthy volunteers, and the area under the curve is proportional to dose.

Resistance of pancreatic carcinoma cells is reversed by coculturing NK-like T cells with dendritic cells pulsed with tumor-derived RNA and CA 19-9

Immunization with defined tumor antigens is limited to the small number of cancers in which specific tumor antigens have been defined but insufficient tumor material is available to produce an antitumor vaccine. In this study, we investigated whether pulsing dendritic cells (DC) using a liposomal transfer technique with a pancreatic tumor cell line-derived RNA can effectively activate NK-like T cells and tumor immunity. Pulsed DC were cocultured with NK-like T cells, i.e., CD3+CD56+ cells, as immunologic effector cells. Target cells resistant to NK-like T-cell-mediated lysis were used. Total tumor-derived RNA transfected into DC was found to completely reverse tumor cell resistance. Total tumor RNA transfection (30 microg) was found to be superior to poly(A)(+) RNA transfection (5 microg) in inducing NK-like T lymphocytes. Interestingly, additional pulsing of DC with the CA 19-9 peptide in a CA 19-9-positive cell line further increased the sensitivity of pancreas carcinoma cells to NK-like T cells. Treatment of tumor RNA with RNase completely blocked the effect of RNA-transfected DC on NK-like T cells, suggesting that intact tumor-derived RNA is needed for reversal of tumor cell resistance. In conclusion, coculture of NK-like T cells with DC transfected with pancreatic tumor cell line-derived RNA reverses pancreatic tumor cell resistance by directly triggering NK-like T lymphocytes.

A computed tomography scan assessment of regional lung volume in acute lung injury. The CT Scan ARDS Study Group

The lobar and cephalocaudal distribution of aerated and nonaerated lung and of PEEP-induced alveolar recruitment is unknown in acute lung injury (ALI). Dimensions of the lungs and volumes of aerated and nonaerated parts of each pulmonary lobe were measured using a computerized tomographic quantitative analysis and compared between 21 patients with ALI and 10 healthy volunteers. Distribution of PEEP-induced alveolar recruitment along the anteroposterior and cephalocaudal axis and influence of the resting volume of nonaerated lower lobes were also assessed. Anteroposterior and transverse dimensions of the lungs of the patients were similar to those of healthy volunteers, whereas cephalocaudal dimensions were reduced by more than 15%. Total lung volume (aerated plus nonaerated lung) was reduced by 27%. Volumes of upper and lower lobes were 99 and 48% of normal values. In addition to an anteroposterior gradient in the distribution of aerated and nonaerated areas, a cephalocaudal gradient was also observed. Nonaerated areas were predominantly found in juxtadiaphragmatic regions. PEEP-induced alveolar recruitment was more pronounced in nondependent than in dependent regions and in cephalad than in caudal regions. A significant correlation between resting volume of nonaerated lower lobes and regional PEEP-induced alveolar recruitment was observed. In ALI, loss of lung volume involves predominantly lower lobes. The thorax shortens along its cephalocaudal axis. PEEP-induced alveolar recruitment predominates in nondependent and cephalad lung regions and is inversely correlated with the resting volume of nonaerated lung.

Busulfan/cyclophosphamide as conditioning regimen for allogeneic bone marrow transplantation for myelodysplasia

PURPOSE

A non-radiation-containing regimen of busulfan and cyclophosphamide (BU/CY) was evaluated for toxicity, relapse, and long-term survival in patients who received allogeneic bone marrow transplantation (BMT) for myelodysplasia (MDS).

PATIENTS AND METHODS

Thirty-eight patients with MDS, including eight with therapy-related MDS, were prepared for BMT using BU/CY.

RESULTS

Fourteen patients remain in first remission 18 to 60 months posttransplant. Five patients relapsed after BMT, and four of these patients died. Eight additional patients died of acute or chronic graft-versus-host disease (GVHD), and 11 died of regimen-related toxicity, primarily systemic mycoses. Overall survival rate at 2 years was 45% (95% confidence interval [CI], 0.30 to 0.61), with a 24% probability of relapse (95% CI, 0.10 to 0.49). Regimen-related toxicity was manifested primarily as hepatic dysfunction in 72% of patients, with 16% developing overt venoocclusive disease (VOD).

CONCLUSION

Non-radiation-containing preparative regimens offer long-term survival in allogeneic BMT for MDS that is comparable to that of radiation-containing regimens, and are useful in patients with therapy-related MDS. Monitoring BU levels may reduce regimen-related mortality and improve survival.

Thalidomide as salvage therapy for chronic graft-versus-host disease

Thalidomide has been reported to be an effective agent for treatment of chronic graft-versus-host disease (CGVHD). To determine the efficacy of this agent in patients with refractory CGVHD a total of 80 patients who failed to respond to prednisone (PSE) or PSE and cyclosporine (CSA) were treated with thalidomide. Sixteen patients (20%) had a sustained response, 9 with a complete remission and 7 with a partial response. Twenty-nine patients (36%) had thalidomide discontinued because of side effects, which included sedation, constipation, neuritis, skin rash, and neutropenia. Side effects were reversible with drug discontinuation except for mild residual neuritis in one case. Rashes and neutropenia have not previously been reported as thalidomide side effects when used for CGVHD treatment. We conclude thalidomide is immunosuppressive and active in the treatment of CGVHD. A high incidence of reversible side effects limited dose intensity and reduced the number of patients who could benefit from treatment.

A molecular basis for MHC class II--associated autoimmunity

Class II major histocompatibility (MHC) molecules have an immunoregulatory role. These cell-surface glycoproteins present fragments of protein antigens (or peptides) to thymus-derived lymphocytes (T cells). Nucleotide sequence polymorphism in the genes that encode the class II MHC products determines the specificity of the immune response and is correlated with the development of autoimmune diseases. This study identifies certain class II polymorphic amino acid residues that are strongly associated with susceptibility to insulin-dependent diabetes mellitus, rheumatoid arthritis, and pemphigus vulgaris. These findings implicate particular class II MHC isotypes in susceptibility to each disease and suggest new prophylactic and therapeutic strategies.

Retroperitoneal fibrosis following treatment for Hodgkin's disease

With improvement and refinement of therapy, the majority of Hodgkin's disease patients are alive and free of disease at 5 years. As these patients continue to be observed, a variety of late complications have been reported. We describe herein three patients who developed retroperitoneal fibrosis following definitive therapy for Hodgkin's disease. The incidence approaches that seen with methysergide.

Molecular composition of an antigen-specific, Ly-1 T suppressor inducer factor. One molecule binds antigen and is I-J-; another is I-J+, does not bind antigen, and imparts an Igh-variable region-linked restriction

Immunized Ly-1+2-T cells (Ly-1 cells) make an antigen-specific soluble suppressor product (Lyl-1 TsiF) that will induce Ly-2+ cells to express suppressive activity but only if the Ly-2+ and the Ly-1 producer cell share genetic polymorphisms that are linked to the Igh locus and in particular that part where the Igh-V (or VH) is encoded. Ly-1 TsiF can be separated into entities, one binds antigen and does not express I-J determinants, and the other is I-J+ and does not bind antigen. Neither of these "subfactors" has biological activity, but a 50:50 mixture of them reconstitutes biological activity that expresses the antigen specificity of the antigen-binding molecule. Any of the three heterologous erythrocytes (antigens) studied can be used for immunization to produce the I-J+ nonantigen-binding factor, i.e., the I-J+ moiety makes no contribution to the factor's specificity. It does, however, determine the intact factor's Igh-V linked restriction. Thus, the antigen combining site of the factor is irrelevant to the factor's Igh-V restriction but crucial for its specificity. The I-J+ molecule does not bind antigen nor influence the factor's antigen specificity but expresses the Igh-V polymorphism (or anti-Igh-V polymorphism) that is required for the transmission of an inductive signal to the factor's Ly-2+ acceptor cell.