The epidemiologic, health-related quality of life, and economic burden of gastrointestinal stromal tumours

BACKGROUND AND OBJECTIVES

Gastrointestinal stromal tumours (GIST) are uncommon tumours believed to arise from interstitial cells of Cajal or their precursors in the gastrointestinal (GI) tract, accounting for a small percentage of GI neoplasms and sarcomas. Given the recent recognition of GIST as a distinct cancer, as well as new treatment options available today, a review of the epidemiologic, health-related quality of life (HRQL), and economic burden of GIST is timely from a payer, provider and patient perspective and may provide guidance for treatment decision making and reimbursement.

METHODS

A systematic literature review of PubMed and five scientific meeting databases, was conducted to identify published studies and abstracts describing the epidemiologic, HRQL and economic impact of GIST. Publications deemed worthy of further review, based on the information available in the abstract, were retrieved in full text.

RESULTS AND DISCUSSION

Thirty-four publications met the review criteria: 29 provided data on GIST epidemiology, one provided cost data, three reported HRQL outcomes, and one reported cost and HRQL outcomes. The annual incidence of GIST (cases per million) ranged from 6.8 in the USA to 14.5 in Sweden, with an estimated 5-year survival rate of 45-64%. On the Functional Illness of Chronic Therapy-fatigue instrument, GIST patients scored 40.0 compared with 37.6 in anaemic cancer patients (0 = worst; 52 = least fatigue). Total costs over 10 years for managing GIST patients with molecularly targeted treatment was estimated at pounds 47 521- pounds 56 146 per patient compared with pounds 4047- pounds 4230 per patient with best supportive care.

CONCLUSIONS

The incidence of GIST appears to be similar by country; the lower estimate in one country could be explained by differences in method of case ascertainment. Data suggest that the HRQL burden of GIST is similar to that with other cancers although this requires further exploration. The value of new therapies in GIST needs to consider not only cost but also anticipated benefits and the unmet medical need in this condition.

Serum macrophage migration inhibitory factor (MIF) levels after allogeneic hematopoietic stem cell transplantation

Macrophage migration inhibitory factor (MIF) may play an important role in the pathogenesis of acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (allo-HSCT), as MIF plays an important role to regulate the production of tumor necrosis factor-alpha (TNF-alpha), one of the inflammatory cytokines which induces and exacerbates aGVHD. We examined the association between serum MIF levels and aGVHD vs. chronic GVHD (cGVHD) in allo-SCT patients in this study. We found a significant increase in the peak serum MIF (14.46 ng +/- 1.47 ng/ml) at onset in patients that developed aGVHD (n = 23, P = 0.009). We also found that mean serum MIF levels in patients who developed extensive type cGVHD within 6 months (12.58 +/- 2.18 ng/ml, n = 13) were significantly higher than MIF levels before allo-HSCT (7.86 +/- 1.17 ng/ml, n = 19, P = 0.04). Therefore, we speculated that serum MIF levels increase during the active phase of both aGVHD and cGVHD.

Sex differences in under and over nutrition among school-going Black teenagers in South Africa: an uneven nutrition trajectory

OBJECTIVES

To investigate the nutritional status of Black South African teenagers by sex and compare it with nutritional profiles of teenagers from other countries.

METHODS

The first South African Youth Risk Behaviour Survey (2002) was adapted to include anthropometric data and this paper reports on the prevalence of under and over nutrition among 5322 Black teenagers, aged 13.0-17.9 years, grades 8-11. Prevalence of over nutrition in this study was compared with other countries using a World Bank country economic classification.

RESULTS

Significant sex differences were observed for under and over nutrition. Boys (18.4%) had a higher prevalence of underweight than girls (2.6%) (P < 0.005), who were more at risk of overweight than boys (20.9%vs. 4.2%) (P < 0.005). Boys (21.9%) were more stunted than girls (9.4%) (P < 0.05), but stunted girls were at greater risk of overweight than boys across all levels of stunting. The prevalence of overweight among boys (4.2%) was lower than in other countries while for girls (20.9%) was similar to several upper middle and high income countries.

CONCLUSION

Gender sensitive strategies are required to address both under and over nutrition among South African teenagers to reduce stunting and future chronic disease epidemics in adulthood. This paper suggests that Black South African teenagers are experiencing an uneven nutritional transition across sex, from under nutrition to over nutrition.

Screening for extended-spectrum beta-lactamase-producing Enterobacteriaceae among high-risk patients and rates of subsequent bacteremia

BACKGROUND

Bloodstream infections due to extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae have been associated with increased hospital costs, length of stay, and patient mortality. However, the role of routine inpatient surveillance for ESBL colonization in predicting related infection is unclear.

METHODS

From 2000 through 2005, we screened 17,872 patients hospitalized in designated high-risk units for rectal colonization with vancomycin-resistant enterococci and ESBL-producing Enterobacteriaceae using a selective culture medium. In patients with a bloodstream infection due to ESBL-producing Enterobacteriaceae (ESBL-BI) during the study period, surveillance results were evaluated for evidence of antecedent ESBL-producing Enterobacteriaceae colonization.

RESULTS

The rate of ESBL-producing Enterobacteriaceae colonization doubled during the 6-year study period, increasing from 1.33% of high-risk patients in 2000 to 3.21% in 2005. Among patients with ESBL-producing Enterobacteriaceae colonization, 49.6% also carried vancomycin-resistant enterococci. The number of ESBL-BIs increased >4-fold in 5 years, from 9 cases in 2001 to 40 cases in 2005. Of 413 patients colonized with ESBL-producing Enterobacteriaceae, 35 (8.5%) developed a subsequent ESBL-BI. Of concern, more than one-half of all ESBL-BIs occurred in patients who were not screened. These 56 patients received a diagnosis of ESBL-BI in the emergency department, when hospitalized in low-risk medical units, or at transfer from an acute or long-term health care facility.

CONCLUSIONS

Colonization with ESBL-producing Enterobacteriaceae is increasing at a rapid rate, and routine rectal surveillance for ESBL-producing Enterobacteriaceae may have clinical implications. However, in our experience, over one-half of patients with an ESBL-BI did not undergo screening through our current surveillance measures. As a result, targeted screening for ESBL-producing Enterobacteriaceae among additional patient populations may be integral to future ESBL-BI prevention and management efforts.

Morphosurgical correlation of outcomes in complete double outlet right ventricle

Even though surgical experience with wide spectrum of double outlet right ventricle (DORV) is available, the experience with extreme form of complete DORV where both great arteries completely arise from the right ventricle is limited. We present our experience with this unique subset where the systemic outflow is far removed from the interventricular foramen and hence, the systemic ventricle. In this situation, biventricular repair can be technically demanding and challenging. Between June 2002 and February 2006, 12 patients underwent biventricular repair of this subset. The VSD was subaortic in all; eight patients had infundibular and valvar obstruction. Aorta was anterior and to the right, with the pulmonary artery far posterior and to the left. The interventricular foramen was patched with a long Gore-Tex patch to route the LV flow to the aorta. Eight patients had infundibular resection and right ventricular outflow tract (RVOT) enlargement with an autologous monocusp pericardial patch. No patient required a valved conduit. There was no operative mortality. In one patient, there was a small residual VSD that was not of haemodynamic significance. There was no RVOT and left ventricular outflow tract obstruction and no RV inflow obstruction. The early and mid-term results are good.

Cost effectiveness of sorafenib versus best supportive care in advanced renal cell carcinoma in Canada

5111

Background: Sorafenib is an oral multi-kinase inhibitor that targets tumour cell proliferation and tumour angiogenesis. In the TARGETs study (phase III trial), sorafenib plus best supportive care (BSC) significantly prolonged progression-free survival (PFS) compared with BSC alone (P<0.000001) in patients with advanced renal cell carcinoma (RCC). The objective of this study was to evaluate the costeffectiveness of sorafenib plus BSC versus BSC alone in advanced RCC from a Canadian provincial Ministry of Health perspective. Methods: A Markov model was developed to project the lifetime survival and costs associated with the two treatment groups. The model tracked patients with advanced RCC through three disease states - PFS, progression, and death. Resource utilization included drug, drug administration, physician visits, monitoring, and adverse events. Costs and survival benefits were discounted annually at 5%. Results: The lifetime per patient costs were $62,426 CDN and $18,898 CDN for sorafenib + BSC and BSC alone, respectively. The life-years gained (LYG) were higher for sorafenib relative to BSC. The incremental cost-effectiveness ratio (ICER) of sorafenib plus BSC versus BSC alone over a lifetime horizon was $36,046/LYG CDN (with a half cycle correction). Univariate sensitivity analyses yielded ICERs below $70,000/LYG CDN. Probabilistic sensitivity analyses showed that the results were moderately sensitive to the clinical variables and less sensitive to the cost variables, yielding ICERs below $100,000/LYG CDN in most cases. Conclusion: Sorafenib is cost effective with an ICER of $36,046/LYG CDN which is below the suggested cost effectiveness threshold of $100,000/QALY ($CDN 1992) or $130,860/QALY ($CDN 2006).

[Table: see text]

End Cutaneous Ureterostomy for the Management of Severe Hydronephrosis

PURPOSE

Although rarely indicated, surgical treatment of severe megaureter can pose a formidable technical challenge, especially in the small infant. We present our experience and outcomes with end cutaneous ureterostomy as a temporizing adjunct to future ureteral reimplantation.

MATERIALS AND METHODS

We performed a retrospective cohort study of patients who underwent end cutaneous ureterostomy between 1993 and 2005. Patient demographics, surgical details and outcomes were recorded.

RESULTS

A total of 29 patients (22 males, 7 females) underwent diversion of 34 renal units. Primary megaureter was diagnosed in 15 patients (17 renal units). Secondary megaureter was found in 10 patients (12 renal units). Postoperative megaureter was diagnosed in 4 patients (5 renal units). Mean patient age at time of diversion was 3.2 months for those with primary megaureter and 1.4 years overall. Bilateral diversion or diversion of a solitary functioning kidney was performed in 14 patients (48%), of whom 4 had renal insufficiency. Nine patients (31%) had a febrile urinary tract infection while awaiting undiversion, with no evidence of renal scarring on followup. Undiversion was performed in 12 patients (13 renal units) with primary megaureter at a mean age of 18 months. Overall, undiversion was performed in 21 patients (23 renal units), and ureteral tailoring was required in only 5 renal units (22%). Mean followup after undiversion was 4.2 years for primary megaureter and 3.9 years overall.

CONCLUSIONS

End cutaneous ureterostomy is a safe and effective procedure to temporize massive hydronephrosis while awaiting definitive ureteral reimplantation.

Thermoelectricity in Molecular Junctions

By trapping molecules between two gold electrodes with a temperature difference across them, the junction Seebeck coefficients of 1,4-benzenedithiol (BDT), 4,4'-dibenzenedithiol, and 4,4''-tribenzenedithiol in contact with gold were measured at room temperature to be +8.7 +/- 2.1 microvolts per kelvin (muV/K), +12.9 +/- 2.2 muV/K, and +14.2 +/- 3.2 muV/K, respectively (where the error is the full width half maximum of the statistical distributions). The positive sign unambiguously indicates p-type (hole) conduction in these heterojunctions, whereas the Au Fermi level position for Au-BDT-Au junctions was identified to be 1.2 eV above the highest occupied molecular orbital level of BDT. The ability to study thermoelectricity in molecular junctions provides the opportunity to address these fundamental unanswered questions about their electronic structure and to begin exploring molecular thermoelectric energy conversion.

A to G transitions at 260, 386 and 437 in DAZL gene are not associated with spermatogenic failure in Indian population

The autosomal DAZL (Deleted-in-Azoospermic-Like) gene, mapped to the short arm of the human chromosome 3, is the precursor for the Y-chromosomal DAZ cluster, which encodes for putative RNA-binding proteins. Mutations in the DAZL have been reported to be associated with spermatogenic failure in Taiwanese population but not in Caucasians. As there was no study on Indian populations, we have analysed the entire coding sequences of exons 2 and 3 of DAZL in a total of 1010 men from Indian subcontinent, including 660 infertile men with 598 non-obstructive azoospermia, 62 severe oligozoospermia and 350 normozoospermic fertile control men, to investigate whether mutation(s) in the DAZL is associated with male infertility. Interestingly, none of our samples (1010) showed A386G (T54A) mutation, which was found to be associated with spermatogenic failure in Taiwanese population. In contrast, A260G (T12A) mutation was observed in both infertile and normozoospermic fertile control men, without any significant association with infertile groups (chi2= 0.342; p = 0.556). Similarly, we have found a novel A437G (I71V) mutation, which is also present in both infertile and normozoospermic fertile control men without any significant difference (chi2 = 0.476; p = 0.490). Our study clearly demonstrates the complete absence of the A386G (T54A) mutation in Indian subcontinent and the other two mutations --A260G (T12A) and A437G (I71V)--observed are polymorpic. Therefore, we conclude that these mutations in the DAZL gene are not associated with male infertility in Indian subcontinent.

Urinary metabolic evaluations in normal and stone forming children

PURPOSE

Urinary stone disease is relatively rare in children and urinary metabolic evaluations have been the standard in our practice. We have previously reported a high rate of urinary metabolic abnormalities in stone forming children. We compared urinary chemistry values in normal and stone forming children.

MATERIAL AND METHODS

A prospective study was performed to assess urinary metabolic profiles in children with no history or a family history of urinary calculi. The 24-hour urine collections were performed and evaluated at an outside central laboratory. Urine chemistry studies were adjusted for creatinine. The data were compared to those on a historical cohort of calcium stone forming children.

RESULTS

A total of 58 samples from normal children and 142 from stone forming children were evaluated. Mean age was 10 years in normal children and 12 years in stone forming children. of the normal and stone forming children 45% and 51%, respectively, were female. Supersaturation levels of calcium oxalate as well as calcium to creatinine levels were significantly higher in children with stones. No data confounding by age or sex was identified by stratification.

CONCLUSIONS

There are significant differences in urinary metabolic evaluations between normal and stone forming children. This may allow more precise treatment to prevent recurrent stone episodes. We continue to perform metabolic evaluations in all children with documented urolithiasis.

Endoscopic injection of dextranomer/hyaluronic acid copolymer to correct vesicoureteral reflux following failed ureteroneocystostomy

PURPOSE

The efficacy of endoscopic injection of dextranomer/hyaluronic acid to correct primary vesicoureteral reflux is well documented. We present experience at 2 institutions with endoscopic treatment for vesicoureteral reflux after failed ureteroneocystostomy.

MATERIALS AND METHODS

A retrospective review was performed of the records of all patients who underwent endoscopic dextranomer/hyaluronic acid injection to correct vesicoureteral reflux following ureteral reimplantation between April 2002 and July 2005. De novo ipsilateral vesicoureteral reflux was noted after repair of primary nonrefluxing megaureters or renal transplantation and persistent vesicoureteral reflux was noted following attempted vesicoureteral reflux repair. Injection was performed using the standard technique if the ureteral orifice was easily accessible, and percutaneously if access was difficult.

RESULTS

Nine male and 9 female patients were identified. Median age was 1.9 years at reimplantation and 6.5 years at injection, and median followup was 19 months. Ten patients underwent extravesical detrusorrhaphy and 8 underwent cross-trigonal reimplantation. Six patients underwent reimplantation for primary megaureter repair and all had resolution of vesicoureteral reflux with injection. Of the 20 renal units 16 (80%) and 15 of 18 patients (83%) had complete resolution of vesicoureteral reflux after 1 injection. One patient had improvement in vesicoureteral reflux and 2 had no improvement. There were no complications resulting from injections.

CONCLUSIONS

Endoscopic treatment of vesicoureteral reflux with dextranomer/hyaluronic acid following extravesical or cross-trigonal reimplantation is safe and efficacious, at least at short-term followup. Endoscopic injection should be considered first line treatment for this situation.

Technique of cultivating limbal derived corneal epithelium on human amniotic membrane for clinical transplantation

BACKGROUND

The technique of transplantation of cultivated limbal epithelium rather than direct limbal tissue isa novel method of "cell therapy" involved in reconstructing the ocular surface in severe limbal stem cell deficiency [LSCD], caused by chemical burns.

AIM

To describe a simple feeder-cell free technique of cultivating limbal epithelium on human amniotic membrane[HAM].

MATERIALS AND METHODS

The limbal tissues (2 mm) were harvested from patients with LSCD. These tissues were proliferated in vitro on HAM supplemented by human corneal epithelial cell medium and autologous serum. Cultures covering more > or = 50% area of 2.5 x 5 cm HAM were considered adequate for clinical use. The cultured epithelium was characterized by histopathology and immunophenotyping.

RESULTS

A total of 542 cultures out of 250 limbal tissues were cultivated in the laboratory from January 2001 through July 2005. The culture explants showed that clusters of cells emerging from the edge of the explants in one-three days formed a complete monolayer within 10-14 days. In 86% of cultures (464 of 542), the growth was observed within one-two days. Successful explant cultures were observed in 98.5% (534 of 542 cultures) with 91% explant cultures showing an area of > or = 6.25 cm2 (6.25 - 12.5 cm2 range). The cultivated epithelium was terminated between 10-14 days for clinical transplantation. The problems encountered were inadequate growth (2 of 542) and contamination (2 of 542).

CONCLUSIONS

We demonstrate a simple technique of generating a sheet of corneal epithelium from a limbal biopsy. This new technique could pave the way for a novel form of cell therapy.

Interpretation of stochastic events in single molecule conductance measurements

The electrical conductance of a series of thiol-terminated alkanes, (1,6-hexanedithiol (HDT), 1,8-octanedithiol (ODT), and 1,10-decanedithol (DDT)) was measured using a modified scanning tunneling microscope break junction technique. The interpretation of data obtained in this technique is complicated due to multiple effects such as microscopic details of the metal-molecule junctions, superposition of tunneling currents, and conformational changes in the molecules. A new method called the last-step analysis (LSA) is introduced here to clarify the contribution of these effects. In direct contrast to previous work, LSA does not require any data preselection, making the results less subjective and more reproducible. Finally, LSA was used to obtain the conductance of single molecules (HDT, (3.6 x 10(-4))G(o); ODT, (4.4 x 10(-5))G(o); DDT, (5.7 x 10(-6))G(o)). The tunneling decay parameter (beta) was calculated, and it was found to be approximately 1.0 per carbon atom.

Nephrotic syndrome associated with chronic graft-versus-host disease after allogeneic hematopoietic stem cell transplantation

Chronic graft-versus-host disease (cGVHD) is the most common late complication of allogeneic hematopoietic cell transplantation (HCT) causing significant morbidity and mortality. The kidneys are not considered a target organ for cGVHD in humans, although animal models show renal damage. Renal involvement in patients with cGVHD, presenting as nephrotic syndrome (NS), has rarely been reported in patients who received allogeneic transplantation. Herein we describe, by far, the largest series of nine patients with NS associated with cGVHD, including two patients who received a reduced-intensity regimen. Pathological features of membranous nephropathy were the most common finding on renal biopsy. The clinical course of the NS was temporally associated with the classical features of cGVHD in all but one of the nine cases. The clinicopathologic features of NS in our series as well as reports in the literature demonstrate an immunopathologic process typical of antibody-mediated damage consistent with cGVHD. Treatment directed against antibody-mediated damage, such as anti-B-cell antibody may play an important role in ameliorating NS associated with cGVHD.

Cost-effectiveness of sorafenib versus best supportive care in advanced renal cell carcinoma

4604

Background: Results from the Phase III TARGETs study showed that sorafenib plus best supportive care (BSC) significantly prolonged progression-free survival (PFS) compared with BSC alone (p < 0.000001) in patients with advanced renal cell carcinoma (RCC). In addition, at a planned interim analysis, overall survival was numerically longer with sorafenib than BSC with a hazard ratio of 0.72. The objective of this study was to evaluate the cost-effectiveness of sorafenib + BSC versus BSC alone in advanced RCC from a US payer perspective. Methods: A Markov model was developed to project the lifetime survival and costs associated with sorafenib + BSC and BSC alone. The model tracked patients with advanced RCC through three disease states - PFS, progression, and death. Transition probabilities between disease states varied for each 3-month period and were obtained from the TARGETs study. Life-years gained were used as a measure of treatment effectiveness. Resource utilization included drug, administration, physician visits, monitoring, and adverse events. Costs and survival benefits were discounted annually at 3%. All costs were adjusted to 2004 US dollars. Scenario sensitivity analyses were conducted. Results: The lifetime per patient costs were $85,571 and $36,634 for sorafenib + BSC and BSC alone, respectively. The life-years gained were higher for sorafenib relative to BSC. The incremental cost-effectiveness ratio (ICER) of sorafenib + BSC versus BSC alone was $75,354 per life-year gained. The key drivers of the model results were survival after progression and PFS probabilities for both treatment groups. Sensitivity analyses showed that the model results were robust to variance in sorafenib and BSC treatment costs. Conclusions: The incremental cost-effectiveness ratio was within the established threshold that society is willing to pay (i.e., $50,000-$100,000). Therefore, sorafenib + BSC appears to be cost-effective in the management of advanced RCC.

[Table: see text]

Thymoquinone, a component of the herb Nigella sativa, suppresses proliferation and viability of prostate cancer cells by down-regulating androgen receptor and E2F-1

20038

Background: Prostate cancer (CaP) that relapses following androgen-ablation therapy is hormone refractory, yet its growth continues to depend on androgen receptor (AR). Therefore, a curative strategy must include structural elimination of AR. Thymoquinone (TQ) is a component of Nigella sativa, an herb that has been used for thousands of years for a variety of diseases including cancer. We examined TQ effect on AR and cell cycle regulatory proteins required for proliferation and viability of CaP cells. Methods: Inhibitory effect of TQ on DNA synthesis and proliferation of exponentially growing LNCaP cells was assessed by 3H-thymidine incorporation into DNA and MTS assay respectively. We examined TQ effect on AR and cell cycle regulatory proteins by Western blot analysis. The effect of TQ on cell cycle progression was determined using synchronized LNCaP cells. Western blots were then used to analyze equal amounts of protein isolated from cells at regular intervals during their progression through the cell cycle in the presence or absence of TQ. Results: We observed a dose-dependent increase in the inhibitory effect of TQ on DNA synthesis and proliferation of LNCaP cells. We also observed a significant decrease in AR and E2F-1, and a dramatic increase in p21, p27, and pRB, and Bax. Synchronized LNCaP cells treated with TQ failed to enter S phase. Western blot analysis revealed that TQ treatment of synchronized cells resulted in: (i) a significant decrease in AR, that normally increases in early- to late-G1phase, and E2F-1, that normally increases in late-G1phase (ii) down-regulation of cyclins A and E, Cdks-2 and 4, and Cdc-6 (iii) induction of p53 and p27. Conclusion: These observations demonstrate that TQ inhibits proliferation and viability of prostate cancer cells by decreasing AR and E2F-1 levels and inducing the proteins that cause cell cycle arrest and promote apoptotic events. Thus TQ may prove to be an effective treatment of hormone refractory CaP and a promising chemo- and/or radiation- sensitizing agent in adjuvant therapy as well. This could represent a novel approach for treatment of prostate cancer by an herbal agent that was shown to spare normal cells in previous studies.

No significant financial relationships to disclose.