Underreporting and Underrepresentation of Racial and Ethnic Minority Patients in Lymphedema Clinical Trials: A Systematic Review

The generalizability of findings from Clinical Trials (CTs) investigating lymphedema treatment modalities requires an accurate representation of the target population. This study aims to evaluate racial and ethnic reporting and representation in lymphedema CTs. A comprehensive systematic literature search was conducted during May 2023 using multiple databases, following the PRISMA guidelines. All CTs published from 2018 to 2023 were included. A total of 84 articles were included in this review, from which 6,546 participants were included in the analysis. Seventy-four (88.1%) articles addressed secondary lymphedema, of which 60 (81.1%) were related to breast cancer. Only 12 (13%) of CTs reported at some extend race or ethnicity. Of these, five (41.6%) reported race and two (16.6%) reported ethnicity according to FDA guidelines. White race had the highest pooled prevalence (80%; 95% CI 72-86%; I2=90%), followed by Black (7%; 95% CI 2- 15%; I2= 94.3%) and Asian (4%; 95% CI 1-8%; I2= 89.9%). In studies reporting ethnicity, participants were predominantly non-Hispanic (92.1%; 95% CI 90 - 94%). There is an underreporting and underrepresentation of racial and ethnic minorities among lymphedema CTs, limiting their generalizability. It is imperative to future development of strategies to enhance diversity in the study sample.

Predicting Quadruple Semitendinosus Graft Size for Anterior Cruciate Ligament Reconstruction by Patient Anthropometric Variables: A Cohort Study of 280 Cases

Introduction:

Pre-operative identification of patients with inadequate hamstring graft for anterior cruciate ligament reconstruction is still a subject of interest. The purpose of this study is to correlate dimension of a harvested dimensions graft with patient physical anthropometric variables.

Materials and methods:

This cohort study included 280 patients (male = 226, female = 54) scheduled for primary anterior cruciate ligament (ACL) reconstruction. Interrelationships between quadruple semitendinosus (ST) graft and anthropometric parameters (age, sex, height, weight, and BMI) were assessed using Pearson Correlation test and regression analysis. Difference among gender was analysed using Mann Whitney and t test. The observed graft diameter was also compared with the literature using Bland – Altman plot.

Results:

Mean age of cohort was 29 years (range, 17-50 years), mean height was 1.69m (range, 1.6-1.9m), mean weight was 75 kg (range, 50-116kg) and mean BMI was 26kg/m2 (range 16.65-40.40kg/m2). Mean quadruple length of harvested ST graft was 7cm (7.1±0.6 cm, range, 5.6-8.8cm) and mean diameter was 8mm (8.2±0.8mm, range, 6.5-10mm). Only height and weight were significantly correlated with graft length and diameter in both sex (p value <0.05). Female, compared to male, had significantly smaller (p<0.0001) and thinner graft (p<0.0001). There was a strong agreement between the literature and our observed graft diameter, but with an overestimated graft diameter in 18.5% of the cases.

Conclusion:

Among anthropometric parameter, only height and weight had moderate positive correlation with graft diameter. Males had longer and wider ST graft in contrast to age-matched female group.

The inferior turbinate flap: a novel technique for prosthetic preparation of a total rhinectomy defect

For total rhinectomy defects, the decision to proceed with a prosthetic versus surgical reconstruction is multifactorial, taking into account patient risk factors, availability of donor tissues, the need for tumor surveillance, and personal preferences. When a prosthetic approach is chosen, the reconstructive surgeon is tasked with preparing the defect to maximize prosthetic retention and prevent ulcerations. Stable bone coverage is critical to achieve this aim. Although skin grafting has been described previously for bone coverage, the periosteum is often stripped. We present a novel use of the inferior turbinate flap for preparation of rhinectomy defects that can be utilized regardless of the presence or absence of the periosteum and provides a more durable coverage than skin grafts.

Management of solid-pseudopapillary neoplasms of the pancreas: a comparison with standard pancreatic neoplasms

Background

Solid-pseudopapillary neoplasms (SPNs) of the pancreas are increasingly diagnosed, but the exact surgical management in terms of extent of the resection is not well defined.

Materials and Methods

Patients operated on in our hospital between January 1993 and March 2005 formed the study groups.

Results

From 659 consecutive resections for pancreatic neoplasms, 12 female patients (1.8%) with a median age of 21 years who underwent resection for (SPN) are compared with the remaining 647 pancreatic resection patients. Jaundice (SPN 0 versus PR 73%, p < 0.001) and weight loss (SPN 0 versus PR 49%, p = 0.001) occurred significantly less often. Neoplasms were distributed equally among the pancreatic head (SPN 5 out of 12 patients versus PR 88%, p < 0.001) and corpus/tail (SPN 6 out of 12 patients versus PR 8%, p < 0.001). The operative time was significantly shorter (SPN 233 min versus PR 280 min, p = 0.012), and there were significantly fewer complications (SPN 1 of 12 patients versus PR 48%, p = 0.007). The mortality was not different (SPN 0 versus PR 1.6%, p = 1.000), and the hospital stay was significantly shorter (SPN 9 days versus PR 15 days, p = 0.012). The median size of the neoplasms was significantly larger (SPN 6.9 cm versus PR 2.5 cm). The median number of lymph nodes harvested was significantly fewer (SPN 1 versus PR 6, p = 0.001), and lymph node metastases occurred significantly less often (SPN 0 versus PR 64%, p < 0.001). The 5-year survival of SPN patients was 100% and is significantly better compared with survival of patients with pancreatic adenocarcinoma (12%, p < 0.001) and ampulla of Vater adenocarcinoma (22%, p = 0.005).

Conclusions

Patients with solid-pseudopapillary neoplasms of the pancreas present differently and the course of the disease is more benign. These patients can be adequately managed by pylorus-preserving pancreatoduodenectomy or spleen-preserving distal pancreatectomy with excellent early and long-term results.

Adjuvant chemotherapy for small intestine adenocarcinoma

BACKGROUND

Although the small intestine represents 75% of the length and over 90% of the mucosal surface of the alimentary tract, it is the site of only about 2% of malignant gastrointestinal tumours. Adenocarcinoma is the most common histological subtype, accounting for about 40% of all malignant small intestinal tumours. The infrequent occurrence when compared with malignancies of the stomach and colon is accompanied by non-specific clinical symptoms. The consequences are a significant delay in diagnosis and the finding of advanced, incurable disease at operation. Wide surgical resection of early lesions is the only potentially curative treatment, but it is possible only in a minority of patients. The rare nature of adenocarcinomas of the small intestine has led to a paucity of information about the benefits of adjuvant chemotherapy but there are reports of overall better survival for those patients that receive combination treatment. Most chemotherapy regimens consist of 5-fluorouracil (5-FU), alone or in combination with a variety of other agents like doxorubicin, cisplatin, mitomycin C, cyclophosphamide and oxaliplatin.

OBJECTIVES

To determine the role of adjuvant chemotherapy in the management of adenocarcinoma of the small intestine compared to another adjuvant treatment, a placebo or no other adjuvant treatment.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (1966 to 2006), EMBASE (1974 to 2006), PubMed and CINHAL using the Cochrane highly sensitive search strategy for randomised controlled trials.

SELECTION CRITERIA

Phase III randomised controlled trials comparing post-operative adjuvant chemotherapy for adenocarcinoma of the small intestine with other adjuvant therapies, placebo or no adjuvant treatment.

DATA COLLECTION AND ANALYSIS

No suitable trials were identified.

MAIN RESULTS

No studies fulfilled the inclusion criteria.

AUTHORS' CONCLUSIONS

There is a need for high quality randomised controlled trials to evaluate the effectiveness of adjuvant chemotherapy in the management of adenocarcinoma of the small intestine.

Palliative management of hilar cholangiocarcinoma

Around 80% of the patients with hilar cholangiocarcinoma are candidates for palliative management due to extensive co-morbidity for major surgery, metastases or advanced loco-regional disease. The primary aim of treatment is to provide biliary drainage with long-term relief from pruritus, cholangitis, pain and jaundice. Endoscopically placed self-expanding metallic biliary stent has low procedure-related complications and is probably the modality of choice for patients with unresectable tumour on preoperative assessment. Percutaneous biliary drainage has comparable results and is an alternative when endoscopic expertise is not available or has failed or there are multiple isolated segments with cholangitis. Surgical cholangiojejunostomy provides lasting biliary drainage but has limitations of associated morbidity and mortality. In the absence of high-quality studies, comparing these modalities the choice of biliary drainage procedure should be guided by the available local expertise. Other modalities of treatment like radiotherapy, chemotherapy and photodynamic therapy currently remain investigational.

Triage score for severity of illness

OBJECTIVE

To evolve a triage scoring system for severity of illness based on clinical variables related to systemic inflammatory response syndrome (SIRS).

DESIGN

Prospective study in a tertiary-care hospital.

METHODS

Consecutive pediatric patients admitted to the ward or pediatric intensive care unit (PICU) were studied. The respiratory rate, heart rate, capillary refill time, oxygen saturation (SpO2), systolic blood pressure and temperature were noted, Sensorium level was assessed on AVPU score. Variables were based on SIRS criteria and criteria mentioned in Advanced Pediatric Life Support (APLS). Each study variable was scored as 0 or 1 (normal or abnormal) and total score for each child obtained. The survival at discharge was correlated with the study variables and the total score. Another score based on the magnitudes of the coefficients in multiple logistic regression analysis was computed and the correlation between this score and mortality was also studied. ROC curve analysis was performed to see the overall predictive ability of the score as well as a cut off at which maximum discrimination occurred.

RESULTS

Of 1099 children studied, 44 died. Of the seven variables, only five variables were abnormal in the study subjects. Except heart rate and respiratory rate, all other variables and age showed significant association with survival status (P < 0.01). The mortality increased with increase in the number of abnormal variables: 0.4% 2.2% 6.1% 15.3% 19.4% and 29.4%for scores of 0,1,2,3,4 and 5 respectively and the linear trend was significant (P < 0.01). Mortality also increased with a decrease in age (P < 0.01). Children with a score of 2 or more (2 or more abnormal clinical variables) had significantly higher mortality as compared to those with no abnormal clinical variables (score = 0). Based on the regression coefficients, the maximum possible score was 9.8. Regression based score was found to predict survival status well. The area under the ROC curve was 0.887, indicating that overall 88.7% of the subjects could be predicted correctly. Maximum discrimination was observed at a score of 2.5 (sensitivity 84.1% specificity 82.2%).

CONCLUSION

For triage scoring, any child with 2 or more abnormal clinical variables should be taken as serious that might lead to death. With a more detailed scoring, score of 2.5 can be taken as cut-off to select children who possibly need admission and closer observation.

Prediction of mortality by application of PRISM score in intensive care unit

OBJECTIVE

Prediction of mortality by application of Pediatric Risk of Mortality (PRISM) score in Pediatric Intensive Care Unit (PICU) patients under Indian circumstances.

DESIGN

Prospective study.

SETTING

PICU of a tertiary care multi-specialty hospital.

METHODS

100 sick pediatric patients admitted consecutively in PICU were taken for this study. PRISM score was calculated. Hospital outcome was recorded as (died/survived). The predicted death was calculated by the formula:

RESULTS

Of 100 patients, 18 died and 82 survived. By PRISM score 49 children had the score of 1-9. The expected death in this group was 10.3% (n = 5.03) and the observed death was 8.2% (n = 4). Among 45 children with the score of 10-19, the expected mortality was 21.2% (n = 9.6) and observed was 24.4% (n = 11). There were 3 patients with the score of 20-29, the expected mortality in this group was 39.3% (n = 1.18) and observed mortality 33.3% (n = 1). There were 3 patients with score > or = 30, observed death 66.3% (n = 2) and expected mortality was 74.7% (n = 2.24). There was no significant difference between expected and observed mortality in any group. (p > 0.5). ROC analysis showed area under the curve of 72%.

CONCLUSION

PRISM score has good predictive value in assessing the probability of mortality in relation to children admitted to a PICU under Indian circumstances.

Optimization of the local inhibition of intestinal adenosine deaminase (ADA) by erythro-9-(2-hydroxy-3-nonyl)adenine: enhanced oral delivery of an ADA-activated prodrug for anti-HIV therapy

Previous in situ perfusion studies in rat ileal segments have demonstrated that high concentrations (>40 microg/mL) of erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), a semitight binding inhibitor of adenosine deaminase (ADA), are effective in completely inhibiting the intestinal metabolism of 6-chloro-2',3'-dideoxypurine (6-Cl-ddP), an ADA activated prodrug of the anti-HIV agent 2', 3'-dideoxyinosine (ddI) designed for improved targeting to the central nervous system. However, the intestinal absorption of EHNA results in complete inhibition of the ADA activity in the mesenteric blood draining the isolated intestinal segment being perfused and may lead to complete inhibition of ADA present in the systemic circulation and other sites, an unacceptable outcome since bioconversion in the target tissue is required for prodrug efficacy. This study examines the feasibility of locally inhibiting ADA present in the intestinal wall using EHNA to increase the intestinal absorption of 6-Cl-ddP. Transport experiments conducted in isolated ileal segments from mesenteric cannulated rats using perfusate containing prodrug and various concentrations of EHNA demonstrated that a 0.1 microg/mL logarithmic mean lumenal concentration of EHNA was effective in increasing the intestinal bioavailability of Cl-ddP to > 90%. Intestinal uptake parameters for EHNA and pharmacokinetic parameters generated in vivo in chronically catheterized rats given intravenous infusions ranging from 12.5 to 310 microg/kg/min were used to demonstrate that <10% of systemic ADA would be inhibited at steady state using the optimal perfusate concentration of EHNA. Thus, in continuous perfusions it is possible to increase the intestinal bioavailability of 6-Cl-ddP to >90% with minimal (<10%) inhibition of systemic ADA. Local inhibition of enzymes may be an effective strategy to increase the oral bioavailability of tissue enzyme-activated prodrugs or other drugs which may also be substrates for intestinal enzymes.

Absorption and intestinal metabolism of purine dideoxynucleosides and an adenosine deaminase-activated prodrug of 2',3'-dideoxyinosine in the mesenteric vein cannulated rat ileum

This study investigates the mechanisms of absorption and the role of intestinally localized purine salvage pathway enzymes on the ileal availabilities of 2',3'-dideoxyinosine (ddI), a substrate for purine nucleoside phosphorylase (PNP); 2'-fluoro-2',3'-dideoxyinosine (F-ddI), a non-PNP substrate; and 6-chloro-2',3'-dideoxypurine (6-Cl-ddP), an adenosine deaminase (ADA) activated prodrug of ddI. The potential for increasing the intestinal availability of 6-Cl-ddP through the use of ADA inhibitors, namely, 2'-deoxycoformycin (DCF) and erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA), is also explored. Drug permeability coefficients across the intestinal epithelium were determined in in situ perfusions in the mesenteric vein cannulated rat ileum based on both drug appearance in blood (Pblood) and disappearance from the lumen (Plumen) and their paracellular and transcellular components were estimated by comparison to the permeabilities of two paracellular markers, mannitol and urea. Values of Pblood for ddI were determined to be (1.1 +/- 0.3) x 10(-6) cm/s, in close agreement with the value of (1.0 +/- 0.3) x 10(-6) cm/s obtained for F-ddI, a PNP resistant analogue of ddI having virtually the same molecular size and lipophilicity as ddI. This indicates that PNP may not play an important role in the low intestinal absorption of ddI. The Pblood for 6-Cl-ddP, (19 +/- 2) x 10(-6) cm/s, was 4.5-fold lower than Plumen, (84 +/- 12) x 10(-6) cm/s, which means that 77 +/- 6% of 6-Cl-ddP was metabolized during its intestinal transport, thus qualitatively accounting for the low oral bioavailability (7%) of 6-Cl-ddP observed in vivo in rats. Extensive intracellular metabolism of 6-Cl-ddP by ADA was confirmed by the high concentrations of ddI found both in the intestinal lumen and blood during 6-Cl-ddP perfusions and by a rate of ddI appearance in blood which was approximately 10-fold higher than ddI controls. Co-perfusion of the potent, hydrophilic ADA inhibitor DCF (Ki = 0. 001-0.05 nM) with 6-Cl-ddP led to only partial inhibition of intestinal ADA, while complete inhibition was obtained using the less potent but more lipophilic inhibitor EHNA (Ki = 1-20 nM). Hence, EHNA may be used to improve intestinal absorption of 6-Cl-ddP in vivo.

Role of brain tissue localized purine metabolizing enzymes in the central nervous system delivery of anti-HIV agents 2'-beta-fluoro-2',3'-dideoxyinosine and 2'-beta-fluoro-2',3'-dideoxyadenosine in rats

PURPOSE

This study examines the central nervous system (CNS) delivery of 2'-beta-fluoro-2',3'-dideoxyadenosine (F-ddA) and 2'-beta-fluoro-2',3'-dideoxyinosine (F-ddI), acid stable analogues of dideoxyadenosine (ddA) and dideoxyinosine (ddI) having reduced susceptibility to purine salvage pathway enzymes important in the metabolism of ddA and ddI, adenosine deaminase (ADA) and purine nucleoside phosphorylase (PNP), respectively. Their CNS delivery compared to that for ddI provides insight into the role of brain tissue ADA and PNP in these processes.

METHODS

Brain and cerebrospinal fluid (CSF) concentration-time profiles were obtained for F-ddI during and after intravenous infusions of F-ddI, and for both F-ddA and F-ddI after F-ddA infusions in normal rats or rats pre-treated with the ADA inhibitor 2'-deoxycoformycin (DCF). Rate constants for CNS entry, efflux and metabolism were estimated by computer fits using plasma concentration-time profiles as the driving force functions.

RESULTS

The CNS delivery of F-ddI did not differ significantly from that for ddI. F-ddA, which is more lipophilic than F-ddI, provided higher brain (approximately 8x) and CSF (approximately 11x) concentrations of total dideoxynucleoside (F-ddA and F-ddI) compared to F-ddI. Deamination by brain tissue ADA to form F-ddI reduced CNS levels of intact F-ddA but provided higher brain parenchyma (5x) and CSF/plasma (3x) ratios of F-ddI relative to F-ddI controls. Thus, F-ddA functions in part as a CNS-activated prodrug of F-ddI. DCF pre-treatment inhibited brain tissue ADA, abolishing the prodrug effect, and enhancing F-ddA concentrations in both brain parenchyma (5x) and CSF (6x).

CONCLUSIONS

PNP metabolism does not appear to play a role in the low CNS delivery of ddI. On the other hand, deamination of F-ddA by brain tissue ADA is an important process, such that F-ddA functions in part as a CNS-activated prodrug of F-ddI. Enhanced CNS uptake of intact F-ddA can be achieved with ADA inhibition.

Role of altered metabolism in dideoxynucleoside pharmacokinetics. Studies of 2'-beta-fluoro-2',3'-dideoxyinosine and 2'-beta-fluoro-2',3'-dideoxyadenosine in rats

Enzymes of the purine salvage pathway play an important role in altering the in vivo pharmacokinetics of 2',3'-dideoxypurine nucleosides. This study examines the pharmacokinetics of enzyme-resistant 2'-beta-fluoro analogues of 2',3'-dideoxyinosine (ddI) and 2',3'-dideoxyadenosine (ddA). 2'-beta-Fluoro-2',3'-dideoxyinosine (F-ddI) is an acid-stable analogue of ddI that is highly resistant to purine nucleoside phosphorylase, the principal enzyme in ddI metabolism. 2'-beta-Fluoro-2',3'-dideoxyadenosine (F-ddA), an acid-stable and purine nucleoside phosphorylase-resistant analogue of ddA, is converted in vivo to F-ddI by adenosine deaminase (ADA) but is a much poorer substrate for this enzyme than is ddA. Both F-ddA and F-ddI have been shown to have activity against human immunodeficiency virus in vitro, and F-ddA has been selected by the National Cancer Institute for clinical trials as a new human immunodeficiency virus reverse transcriptase inhibitor. The pharmacokinetics of F-ddI and ddI were compared at equivalent doses in chronically catheterized rats. Because ddI and F-ddI are isosteres having nearly identical lipophilicity, this comparison is likely to reflect primarily metabolic differences. The clearance of F-ddI was substantially reduced, in comparison with that of ddI (27.3 ml/min/kg vs. 90.9 ml/min/kg), resulting in higher systemic concentrations at steady state and prolonged retention of F-ddI after termination of infusions, consistent with a significant metabolic component in the clearance of ddI. Concentrations of F-ddA and F-ddI during and after infusions of F-ddA were determined in both untreated and 2'-deoxycoformycin-pretreated rats. In untreated rats, F-ddA was rapidly eliminated from plasma, with a total clearance of 68.5 ml/kg/min. Metabolic clearance of F-ddA to F-ddI accounted for 58% of this value (bioconversion t1/2 = 9.8 +/- 1.9 min). Pretreatment with 2'-deoxycoformycin, an ADA inhibitor, reduced the clearance of F-ddA to 23.8 ml/min/kg, leading to 2.9 +/- 0.4-fold higher steady-state plasma concentrations of F-ddA, in agreement with a 2.5-fold enhancement predicted by a compartmental model assuming complete ADA inhibition.

Quantitative assessment of blood-brain barrier damage during microdialysis

In view of the increasing use of microdialysis for monitoring drug uptake into the brain, the consequences of tissue/blood-brain barrier (BBB) damage that occurs on microdialysis probe insertion on the extent and rate of solute uptake need to be more carefully examined. In this study, both microdialysis and a classic method were used to compare the apparent brain uptake of two polar permeants, [3H]sucrose and [14C]urea. The blood-to-brain transfer constants of these compounds differ significantly, with the value of urea exceeding that of sucrose by a factor of approximately 20 when compared by the classic one-point-per-animal method. The BBB selectivity to these nonmetabolized permeants as assessed by microdialysis provides a sensitive measure of the integrity of the BBB to polar nonelectrolytes within the molecular size range of most drugs. The following evidence for blood-brain barrier damage during microdialysis sampling was obtained: (1) the loss of [3H]sucrose from the extracellular fluid in brain on termination of an intravenous infusion is biphasic, with the initial phase evident immediately on termination by the infusion, suggesting that a fraction of the microdialysis probe resides in a region in rapid equilibrium with plasma; (2) complete loss of selectivity in the rate constants for CNS entry of sucrose vs. urea and (3) there were substantially higher area under the concentration vs. time curve AUCECF/AUCplasma ratios for both sucrose and urea generated by microdialysis than the corresponding ratios (AUCCSF/AUCplasma or AUCbrain/AUCplasma) obtained by classic methods. These results suggest that the BBB to small molecule transport likely remains compromised for some time after microdialysis probe insertion.

Enhanced oral bioavailability of DDI after administration of 6-Cl-ddP, an adenosine deaminase-activated prodrug, to chronically catheterized rats

PURPOSE

6-Cl-2',3'-dideoxypurine (6-Cl-ddP), an adenosine deaminase (ADA) activated prodrug of ddI, may be an effective antiretroviral agent for the treatment of AIDS dementia due to its ability to deliver increased concentrations of ddI to brain tissue. To examine the feasibility of administering this drug orally, the oral and hepatic portal bioavailabilities of 6-Cl-ddP were determined. In addition, the oral and portal bioavailabilities of ddI after administration of the prodrug were compared to those from administration of ddI itself.

METHODS

Pharmacokinetic and bioavailability studies were conducted in fully conscious, chronically catheterized rats in a randomized crossover design. Plasma ddI and 6-Cl-ddP concentration-time profiles were determined by HPLC.

RESULTS

6-Cl-ddP has poor apparent oral bioavailability (7% +/- 3%, n = 3) but high bioavailability after portal administration (97% +/- 11%), suggesting either poor absorption or extensive gut wall metabolism. The appearance of > 50% of the dose as ddI in the systemic circulation after an oral dose of 6-Cl-ddP rules out poor absorption of the prodrug, and confirms expectations of high ADA activity in the gastrointestinal tract. Gastric administration of 6-Cl-ddP resulted in a > 10-fold increase in the oral bioavailability of ddI, from 3-7% to > 50%, and a significant decrease in the variability in apparent bioavailability.

CONCLUSIONS

These data indicate that lipophilic adenosine deaminase activated prodrugs of dideoxypurine nucleosides may have limited utility for improving CNS delivery after oral administration but may be useful in enhancing the oral bioavailability of highly polar and therefore poorly absorbed dideoxynucleosides.