Mitral paravalvular leak closure by antegrade percutaneous approach using amplatzer PFO closure device

Percutaneous closure of paravalvular leaks is becoming a more widely practiced technique. We describe the technique we used to deploy an Amplatzer PFO closure device to treat a prosthetic mitral paravalvular leak. The procedure was performed under real time 3D trans-oesophageal echo and fluoroscopic guidance requiring a trans-septal puncture and utilising an 035″ Safari wire which was developed for TAVR implantation. An excellent result was achieved acutely and at 4 month follow-up. © 2016 Wiley Periodicals, Inc.

The morbidity and mortality of hepaticojejunostomies for complex bile duct injuries: a multi-institutional analysis of risk factors and outcomes using NSQIP

INTRODUCTION

Bile duct injury (BDI) is an infrequent but morbid complication of cholecystectomy. High-grade BDI repairs requiring hepaticojejunostomies are complex and associated with increased morbidity and mortality. This study sought to establish the increased risk associated with complex bile duct repair at a multi-institutional level in the United States.

METHODS

Using the ACS-NSQIP Participant Use File, all patients who underwent a hepaticojejunostomy for bile duct repair between 2005 and 2012 were identified. Clinical data, perioperative risk factors and morbidity and mortality rates were calculated.

RESULTS

Of the 293 BDI patients, 102 (65.2%) were female and the mean age was 49.8 years. The 30-day morbidity and mortality rates were 26.3% and 2%, respectively. Univariable analysis identified male gender, ASA class, functional status, diabetes, hypertension and chronic steroid use to be associated with increased morbidity. A higher ASA class was associated with increased postoperative sepsis and chronic steroid use was associated with increased overall morbidity on multivariable analysis. The morbidity rates for BDI repair within 30 days of injury vs. later repair were similar (24% vs. 23%), but the mortality rate was higher for the earlier repair group (5% vs. 0%, p = 0.012).

CONCLUSIONS

Within the largest multi-institutional analysis of 30-day outcomes after hepaticojejunostomies for BDI in the US, morbidity and mortality rates were established at 26.3% and 2% respectively. ASA class and preoperative functional status remain the main risk factors for surgery. Earlier repair in the face of ongoing sepsis and disability is associated with worse outcomes. A multidisciplinary approach at a specialized center aimed at controlling infection and improving functional status prior to surgical reconstruction is recommended.

Evaluation of chlorine dioxide based product as a hatchery sanitizer

Formaldehyde is commonly used to overcome contaminants introduced by hatching eggs or water supply in the hatcher cabinets. However, health risks associated with its use make economical alternatives important. This project evaluated a chlorine dioxide based product (CDBP) (0.3% concentrate) as a hatchery sanitizer in decontaminating microbial populations on the shell surface of hatching eggs (>18 d old), as well as its impact on hatchability and chick performance. Hatchers (0.20 m2) designed to hold approximately 50 eggs and equipped with circulation fans, heaters, and thermostats were used for the evaluation. For each of the 2 trials conducted, 450 hatching eggs were obtained and incubated in a common setter. Eggs used in trial 1 were floor eggs whereas in trial 2 nest eggs were used. On d 18 of incubation, eggs were removed from the setter, and viable eggs were randomly allocated to 9 hatchers. Pre-treatment egg rinse samples (10 eggs per hatcher) were collected for initial microbial analysis. Three hatchers were treated with CDBP and 3 hatchers with a formaldehyde based product (FBP). Three untreated hatchers served as control (C). Prior to hatch, 10 eggs/incubator, not previously rinsed, were used for post treatment microbial counts. The hatched chicks were reared until d 21 in floor pens with a common starter diet. For the CDBP treated eggs, hatchability and chick performance (weight gains, mortality, and FCR on d 7 and d 21) were similar to the other treatments. The application rate of CDBP evaluated in this study was not an effective antimicrobial alternative to formaldehyde for sanitizing hatching eggs in hatcher cabinets prior to hatch.

Using endoscopy to minimize the extent of resection in the management of giant GISTs of the stomach

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Giant gastric GISTs are usually managed with neo-adjuvant therapy followed by a partial or total gastrectomy.

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We present a case of where intraoperative endoscopy was used to limit the extent of resection.

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Simultaneous intra-operative endoscopy demonstrated a 2 mm fistula on the lesser curvature of the stomach. A stapler was used to encompass the mass and the fistulous opening.

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A frozen-section showed clear margins and the endoscope was used to confirm luminal patency and perform an air-leak test.

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Oncologic principles of minimal tissue handling and negative margins were observed.

Introduction

Presentation of case

Discussion

Conclusion

Spontaneous endometriosis associated with an umbilical hernia: A case report and review of the literature

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Primary umbilical endometriosis is rare and the presence of an underlying hernia makes it a diagnostic challenge.

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Only 7 cases have been reported in the literature.

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Our patient underwent an en-bloc resection of the hernia sac, endometrioma and umbilicus with reconstruction. There is no disease recurrence at 6 months.

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MRI is the preoperative imaging modality of choice and there is a limited role for preoperative FNA and medical management.

Introduction

Umbilical endometriosis occurring in the presence of an underlying hernia is extremely rare and presents a diagnostic challenge for the general surgeon. We present an interesting case and perform a comprehensive review of the literature.

Methods

Medline and PubMed were queried for all cases of spontaneous umbilical endometriosis associated with an umbilical hernia. Data was analyzed and is presented along with an interesting case.

Results

Only 7 cases have been reported in the literature. Median age was 38 years. Time to presentation was long (up to 5 years) and the majority had cyclical symptoms related to menstruation. All patients, including our case, were treated surgically.

Discussion

Spontaneous umbilical endometriosis with an underlying hernia is often missed preoperatively. Preoperative suspicion warrants axial imaging for better operative planning and patient counseling. Surgery consists of enbloc excision of the umbilicus, implant and the hernia sac to avoid residual disease and reduce recurrence. The hernia defect can be repaired primarily or using mesh and the umbilicus reconstructed using skin flaps if necessary.

Conclusions

Surgery is the mainstay of therapy for umbilical endometriosis associated with an underlying hernia. Clinical suspicion warrants preoperative imaging, and follow-up with a gynecologist is essential to address any pelvic disease.

A new method to improve the objectivity of early Six Sigma analysis

Purpose

A process improvement sampling methodology, known as process variation diagnostic tool (PROVADT), was proposed by Cox et al. (2013). The method was designed to support the objectivity of Six Sigma projects performing the measure-analyse phases of the define-measure-analyse-improve-control cycle. An issue in PROVADT is that it is unable to distinguish between measurement and product variation in the presence of a poor Gage repeatability and reproducibility (R&R) result. The purpose of this paper is to improve and address PROVADT’s sampling structure by enabling a true Gage R&R as part of its design.

Design/methodology/approach

This paper derives an enhanced PROVADT method by examining the theoretical sampling constraints required to perform a Gage R&R study. The original PROVADT method is then extended to fulfil these requirements. To test this enhanced approach, it was applied first to a simulated manufacturing process and then in two industry case studies.

Findings

The results in this paper demonstrates that enhanced PROVADT was able to achieve a full Gage R&R result. This required 20 additional measurements when compared to the original method, but saved up to ten additional products and 20 additional measurements being taken in future experiments if the original method failed to obtain a valid Gage R&R. These benefits were highlighted in simulation and industry case studies.

Originality/value

The work into the PROVADT method aims to improve the objectivity of early Six Sigma analyses of quality issues, which has documented issues.

Use of information and communication technology amongst New Zealand dental students

Although international studies have shown an increasing use of information and communication technology (ICT) amongst dental students, there are no published studies specific to New Zealand (NZ). The aim of this research was to identify device ownership and academic utilisation patterns amongst New Zealand dental students, including preferences and perceptions, and barriers to use. All currently enrolled dental students (322) were invited to complete a 15-item questionnaire. Data were statistically analysed in SPSS version 20.0. Qualitative data were analysed using a general inductive technique. The participation rate was 78.6% (N = 253 of 322). The majority of respondents personally owned laptop computers (98%) and smartphones (80.2%). A total of 10.8% of participants used a desktop computer everyday for academic purposes, whilst 78.7% used a laptop computer daily, and 54.7% a smartphone. New Zealand dental students demonstrated a high usage of ICT for their coursework with varied use of different online resources. The most frequently used online resources were search engines, social networking sites and lecture slides provided on Blackboard(®) . A high perceived value was placed on both audio podcasts and video podcasts despite the high value also placed on the traditional lectures. Although most participants (84.5%) felt that their ICT knowledge was adequate to meet academic requirements, a small number (1.6%) did not agree.

Role of nutritional status and intervention in oesophageal cancer treated with definitive chemoradiotherapy: outcomes from SCOPE1

BACKGROUND

Malnutrition is common in oesophageal cancer. We aimed to identify nutritional prognostic factors and survival outcomes associated with nutritional intervention in the SCOPE1 (Study of Chemoradiotherapy in OesoPhageal Cancer with or without Erbitux) trial.

METHODS

Two hundred and fifty eight patients were randomly allocated to definitive chemoradiotherapy (dCRT) +/- cetuximab. Nutritional Risk Index (NRI) scores were calculated; NRI<100 identified patients at risk of malnutrition. Nutritional intervention included dietary advice, oral supplementation or major intervention (enteral feeding/tube placement). Univariable and multivariable analyses using Cox proportional hazard modelling were conducted.

RESULTS

At baseline NRI<100 strongly predicted for reduced overall survival (hazard ratio (HR) 12.45, 95% CI 5.24-29.57; P<0.001). Nutritional intervention improved survival if provided at baseline (dietary advice (HR 0.12, P=0.004), oral supplementation (HR 0.13, P<0.001) or major intervention (HR 0.13, P=0.003)), but not if provided later in the treatment course. Cetuximab patients receiving major nutritional intervention had worse outcomes compared with controls (13 vs 28 months, P=0.003).

CONCLUSIONS

Pre-treatment assessment and correction of malnutrition may improve survival outcomes in oesophageal cancer patients treated with dCRT. Nutritional Risk Index is a simple and objective screening tool to identify patients at risk of malnutrition.

Intestinal stenosis of Garré: A rare cause of small bowel obstruction in the virgin abdomen

INTRODUCTION

Small bowel obstruction (SBO) in the virgin abdomen usually requires operative intervention. Intestinal stenosis of Garré is a rare and frequently missed cause of SBO following hernia repair.

METHODS

We describe a case of intestinal stenosis of Garré and provide a comprehensive review of the literature. Statistical analysis was performed using IBM SPSS Statistics V.22 software and included descriptive analysis.

RESULTS

Most males developed a delayed stricture following an inguinal hernia repair (93.3%). 84.6% of females, on the other hand, developed intestinal stenosis following repair of a femoral hernia. 87.5% of strictures developed on the right side. The timing of development of a bowel obstruction is very variable and ranges from 5days to 22 years. 22 patients (68.8%), however, presented with an obstruction within 5 months of hernia repair.

CONCLUSIONS

Intestinal stenosis of Garré is an under-reported cause of delayed stricture formation.It is most common following right inguinal hernia repair in men and right femoral hernia repair in women.

Comparison of the Mechanism of Toxicity of 3′-Azido-3′-Deoxythymidine and 3′-Fluoro-3′-Deoxythymidine in Human Lymphocytes

The thymidine analogue 3′-azido-3′-deoxythymidine (AZT), whilst a useful drug for the treatment of acquired immunodeficiency syndrome, produces toxic side-effects which can be severe and can interfere with therapy. The toxic mechanism of AZT is unknown. We have investigated the relationship between the phosphorylation and effect on natural dNTP pools of 3′-azido-3′-deoxythymidine and the closely related 3′-fluoro-3′-deoxythymidine and their toxicity in human lymphocytes. We attempted to reduce the toxicity by co-administration of natural nucleosides.

The toxicity of 3′-fluoro-3′-deoxythymidine could be reduced with thymidine or deoxyuridine five- and 10-fold, respectively. The toxicity of 3′-azido-3′-deoxythymidine could be reduced twofold with cytidine or uridine but was increased by all other nucleosides, including thymidine. Neither analogue caused significant changes in the dNTP pools at cytotoxic concentrations; the effect of the nucleosides in reducing toxicity was not owing to replacement of a depleted dNTP. Thymidine reduced the phosphorylation of 3′-azido-3′-deoxythymidine and 3′-fluoro-3′-deoxythymidine 6 and 17 times, respectively.

3′-azido-3′-deoxythymidine and 3′-fluoro-3′-deoxythymidine appear to have different mechanisms of toxicity. The toxic mechanism of 3′-fluoro-3′-deoxythymidine is probably inhibition of cellular DNA synthesis by the triphosphate. The toxicity of 3′-azido-3′-deoxythymidine in lymphocytes does not appear to be directly related to the amounts of the phosphorylated forms. The mechanism may be interference with RNA metabolism or precursors, perhaps by the nucleoside.

Intracellular Metabolism of 3′-Azido-3′-Deoxythymidine in the Presence of Ganciclovir or Foscarnet

Comparisons were made between the intracellular phosphorylation of 3′-Azido-3′-deoxythymidine (AZT) alone and in combination with ganciclovir (GCV) or foscarnet (PFA) in lymphocytes, uninfected fibroblasts and CMV-infected fibroblasts. The effects of AZT and the combinations of AZT with GCV or PFA on cellular dNTP pools were also examined. The phosphorylation of AZT was not altered by the presence of GCV or PFA in lymphocytes, and neither AZT nor the combinations of AZT with GCV or PFA changed the levels of cellular dNTP pools in these cells. AZT was phosphorylated to a greater extent in lymphocytes when compared to fibroblasts, but the proportion of AZT di- and triphosphates was greater in fibroblasts. The infection of fibroblasts with CMV enhanced AZT phosphorylation and increased the levels of cellular dNTP pools. GCV caused a specific reduction in AZT phosphorylation in CMV-infected fibroblasts, with a seven-fold drop in AZT triphosphate compared to AZT alone. GCV did not affect AZT phosphorylation in uninfected fibroblasts, nor did GCV reduce the dTTP pool compared to AZT alone. The effects of GCV upon AZT phosphorylation in CMV-infected cells may shed light on the antagonistic effects of GCV upon the anti-HIV activity of AZT, and are of importance for the development of effective combination therapies for the treatment of AIDS patients infected with CMV.

Studies on the Reversal of Azidothymidine Toxicity in Human Lymphocytes by Cytidine and Uridine

The toxicity of 3′-azidothymidine (AZT) in human lymphocytes has been shown previously to be reversed by co-incubation with the ribonucleosides cytidine or uridine. In the present paper, the effects of 3′-azidothymidine and cytidine/uridine, both alone and in combination, were studied upon key processes in lymphocytes in order to discover more about the mechanism of toxicity reversal.

In these experiments 3′-azidothymidine had only minor effects on the ribonucleoside triphosphate pools. Cytidine increased the CTP pool, and uridine the UTP pool. Co-incubation with AZT caused similar changes to incubation with cytidine or uridine alone. Toxicity reversal was not linked to replacement of deficient ribonucleoside triphosphate pools.

3′-Azidothymidine caused the excretion of thymidine from lymphocytes. Incubation with cytidine and uridine increased the intracellular cytidine and uridine pools, respectively. Co-incubation with 3′-azidothymidine increased still further the intracellular cytidine and uridine pools. Cytidine and uridine did not affect the intracellular 3′-azidothymidine pool.

The toxicity of 3′-azidothymidine was increased by co-incubation with the bases adenine, guanine, hypoxanthine, and uracil, but not by dihydrouracil, thymine, or xanthine.

Comparison of the Intracellular Metabolism of 3′-Azido-3′-Deoxythymidine and 3′-Fluoro-3′-Deoxythymidine in Lymphocytes in the Presence of 5-Fluoro-2′-Deoxyuridine

The mechanism of action of 2′, 3′-dideoxythymidine analogues such as azidothymidine (AZT) and fluorothymidine (FLT) is thought to be chain termination and inhibition of reverse transcriptase by the triphosphate. However, little triphosphate is formed intracellularly relative to monophosphate and diphosphate. Azidothymidine and fluorothymidine are phosphorylated intracellularly by the thymidine salvage pathway and therefore must compete with thymine nucleotides for phosphorylation, which may limit the rate of phosphorylation. We have investigated the degree to which competition with thymidine limits the phosphorylation of azidothymidine and fluorothymidine. In this paper we show that inhibition of thymidylate synthase by 5-fluoro-2′-deoxyuridine monophosphate increases the phosphorylation of azidothymidine and fluorothymidine by reducing the pools of thymine nucleotides and therefore removing the competition. 5-fluoro-2′-deoxyuridine abolished the pools of TTP and dGTP and caused the appearance of dUTP in treated lymphocytes. Three times more triphosphate was formed in cells treated with 5-fluoro-2′-deoxyuridine. Ten times more fluorothymidine triphosphate than azidothymidine triphosphate was formed. The results suggest that while competition with intracellular thymine nucleotides does hinder the phosphorylation of AZT and FLT, the major limiting factor is their ability to act as substrates for the phosphorylating enzymes.

Metabolism of 3′-Azido-3′-Deoxythymidine and 3′-Fluoro-3′-Deoxythymidine in Combination in Human Immunodeficiency Virus Infected Lymphoblastoid Cells

A combination of 3′-azido-3′-deoxythymidine (AZT) with 3′-fluoro-3′-deoxythymidine (FLT) has been shown previously to give synergistic inhibition of human immunodeficiency virus replication and greatly reduced cytotoxicity in vitro. The phosphorylation of the compounds, and their effect upon the natural deoxynucleoside triphosphate pools, were compared in CEM, H9, and HIV-infected H9 lymphoblastoid cells, both for the compounds when used alone and when combined together.

Higher levels of FLT triphosphate than AZT triphosphate, and higher levels of AZT monophosphate than FLT monosphosphate, were formed in all cell types. Both compounds were phosphorylated most efficiently in CEM cells, whereas they were least efficiently phosphorylated in infected H9 cells.

Owing to competition, the phosphorylation of both analogues was reduced when used in combination, compared to the phosphorylation of the separate compounds. The phosphorylation of the separate compounds was therefore at a maximum and was not increased by combining the compounds. The two compounds competed equally with each other for phosphorylation when used at a ratio of AZT: FLT of 5: 1.

Both analogues severely reduced the deoxynucleoside triphosphate pools in uninfected and human immunodeficiency virus-infected H9 cells, but not in CEM cells. The effects of the two compounds were similar to those found when the compounds were combined, and thus H9 cells were shown to be much more sensitive to the effects of the analogues upon deoxynucleoside triphosphate pools than CEM cells were.

Thus the synergistic combination of 3′-azido-3′-deoxythymidine and 3′-fluoro-3′-deoxythymidine was shown to have a similar metabolism and a similar effect upon cellular deoxynucleoside triphosphate pools to the individual compounds.

Antiviral Activity against VZV and HSV Type 1 and Type 2 of the (+) and (−) Enantiomers of (R,S)-9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine, in Comparison to other Closely Related Acyclic Nucleosides

The separate (+) and (−) enantiomers of the acyclic guanosine analogue 9-[4-hydroxy-2-(hydroxymethyl)-butyl]guanine (2HM-HBG) were tested for inhibition of varicella-zoster virus (VZV), herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2). In all cases the (−) enantiomer was the most active enantiomer. The (+) enantiomer was 10 times less active than the racemate against VZV and inactive against HSV-1 and -2.

The parent compound, 9-(4-hydroxybutyl)guanine, containing an unbranched side chain, was inactive against VZV, whereas substitution with a hydroxymethyl group at the 2 or 3 position of the side chain conferred anti-VZV activity. The effect of hydroxymethyl substitution may increase the recognition of the compound by the VZV thymidine kinase by increasing its similarity to the natural substrate thymidine. Further substitution of the side chain of the parent compound with oxygen, fluorine or hydroxyl groups did not confer antiviral activity against VZV.

Two VZV strains were isolated which could be grown in the presence of high concentrations of 2HM-HBG and which were also cross-resistant to other nucleoside analogues. These strains induced very little viral thymidine kinase activity in infected cells and thus were probably deficient for a functional thymidine kinase.

2HM-HBG exhibited a persistent antiviral effect even after the nucleoside was removed from the medium of VZV-infected cells, whereas acyclovir did not show this effect.

Intracellular Metabolism of 3′-azido-3′-deoxythymidine and 2′,3′-dideoxyinosine in Combination in the Absence and Presence of Ribavirin

We examined the intracellular phosphorylation of 3′-azido-3′-deoxythymidine (AZT) and 2′,3′-dideoxyinosine (ddl) and the effects on rNTP and dNTP pools when AZT and ddl were incubated separately and in combination in lymphocytes. We also compared the effect of adding ribavirin (RBV) to the two-drug combination of AZT + ddl. AZT and ddl, used singly or in combination, had no effect on the dNTP pools of CEM lymphoblastoid cells. Neither did the combination of AZT + ddl have any effect on the rNTP pools. RBV, a known inhibitor of IMP dehydrogenase, caused a decrease in GTP and an increase in dTTP whether incubated alone or with the drug combination of AZT + ddl. The addition of AZT + ddl therefore did not alter the effects of RBV upon cellular nucleotide pools. AZT was phosphorylated to a much greater extent than ddl. The activation of ddl to ddA-TP was increased 2-fold in the presence of AZT, whereas AZT phosphorylation was unchanged when combined with ddl. This increase in ddl activation may explain in part the synergistic antiviral activity of the combination of AZT + ddl. The increased activation was not due to increased phosphorylation of ddl resulting from IMP dehydrogenase inhibition. The addition of 10 μm RBV to the two-drug combination of AZT + ddl did not change the intracellular phosphorylation of AZT or ddl. The activation of ddl to ddA-TP, when combined with AZT, appeared to be maximal and could not be further increased by addition of RBV to this combination.

Effect upon the anti-HIV Activity of 3′-Azido-3′-Deoxythymidine and 3′-Fluoro-3′-Deoxythymidine of Combination with anti-Herpes Nucleoside Analogues

The treatment of the severe and often life-threatening herpesvirus infections which commonly occur in AIDS patients is complicated by the need to treat simultaneously with drugs directed against the human immunodeficiency virus (HIV). Combining together different drugs in this way can lead to effects upon the activities of the individual drugs, such as synergism or antagonism. The effect upon the anti-HIV activity of 3′-azido-3′-deoxythymidine (AZT) and 3′-fluoro-3′-deoxythymidine (FLT) of combination with the anti-herpesvirus drugs 9-(1,3-dihydroxy-2-propoxymethyl-)guanine (DHPG; ganciclovir) and (-)-9-[4-hydroxy-2-(hydroxymethyl)butyl]guanine ([-]-2HM-HBG) was investigated.

Neither DHPG nor (-)-2HM-HBG showed antiviral activity against HIV-1 up to 50 [AM. When combined with AZT or FLT at ratios of antiherpes:anti-HIV drug of 10:1 or greater, both DHPG and (-)-2HM-HBG antagonized the anti-HIV activity of AZT and FLT. When combined at a lower ratio (1:1), there was no effect upon the anti-HIV activity of either AZT or FLT. The phosphorylation of FLT was found to be unchanged in the presence of DHPG or (-)-2HM-HBG, indicating that the mechanism of the antagonism was not owing to an effect of DHPG or (-)-2HM-HBG upon the metabolism of the anti-HIV drugs.

The results suggest that combination chemotherapy with the anti-herpes drugs DHPG/(-)-2HM-HBG and AZT/FLT should be used cautiously. The possibility of such antagonistic interactions should be borne in mind when considering the choice of drug and ratio for treatment of herpesvirus infections in AIDS patients on anti-HIV therapy.

Optimal management of GIST tumors located near the gastroesophageal junction: Case report and review of the literature

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There are several endoscopic, laparoscopic and open surgical procedures available for the management of GIST tumors near the GE junction.

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We present a case-report utilizing both endoscopy and laparoscopy to facilitate resection using the non-touch lesion-lifting technique.

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Pathology demonstrated a 4.7 cm GIST. The patient was discharged on post-operative day 3 with no complications.

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We include a full literature review and describe the various combined modalities available for successful resection.

Introduction

The safety and oncologic outcome of laparoscopic gastric GIST resection is well established especially for lesions <5 cm in diameter. The optimal management of GIST tumors near the GE junction remains unclear.

Methods

We present a case-report of a 4.7 cm GIST tumor near the GE junction managed by endoscopically-assisted laparoscopic wedge resection (EAWR). We present a review of the literature highlighting the various combined laparo-endoscopic techniques available.

Results

We used the non-touch lesion-lifting method to laparoscopically resect the GIST tumor under endoscopic guidance. There were no complications and the patient was discharged on postoperative day 3.

Conclusions

Endoscopically-assisted laparoscopic wedge resections are feasible and safe for GIST tumors near the GE junction.

Biologic mesh spacer placement facilitates safe delivery of dose-intense radiation therapy: A novel treatment option for unresectable liver tumors

INTRODUCTION

Patients with unresectable liver tumors who fail initial treatment modalities have a poor prognosis (<1 yr). Although effective, delivery of high dose radiation therapy to these tumors is limited by proximity of radiosensitive bowel. We have previously reported that placement of a biologic mesh spacer (BMS) can effectively displace the bowel allowing for dose-intense radiation to be delivered with low short-term toxicity. The purpose of this study was to assess and report the long-term safety and oncologic outcomes of this cohort.

METHODS

From 2012 to 2014 seven patients with unresectable hepatic malignancy (6 IHCC, 1 CRLM) underwent BMS (acellular human dermis) placement (2 open, 5 MIS) prior to radiation therapy. Prospective registry data were reviewed for tumor and treatment details, progression, metastasis and survival. RTOG guidelines were used to define radiation toxicities.

RESULTS

Mean patient age was 50.4 years (30-62 years) and 4 patients were male (57.1%). Prior to surgery, all patients had been treated for an average of 12.5 months with surgery, chemotherapy, radiation and/or TACE. After surgery, all patients recovered well and received a mean radiation dose of 76.1 Gy (58.1-100 Gy) over 13-25 fractions. 1 patient received SBRT; 4 fractions, 10 Gy each. Maximum dose delivered was 100 Gy (Biologic Equivalent Dose of 140 Gy, α/β = 10). Mean time to initiation of radiation therapy was 24 days (12-48 days) from surgery. No significant GI toxicity was recorded, and no GI bleeding or ulcers were observed. Mean follow-up after XRT was 18.2 months (5.5-31 months). Three patients had no loco-regional progression of disease. 2 patients had infield progression of liver disease and another had progressive lymphadenopathy. 3 patients developed pulmonary metastasis, at a mean time to distant failure of 3 months. There are 4 survivors over 2-years from surgery.

CONCLUSION

For patients with unresectable liver tumors, placement of a BMS enhances the safety and efficacy of high-dose radiotherapy, providing a survival benefit via delay in time to progression compared to traditional treatments with no significant short or long term GI toxicity.