Clinical management and outcome of head and neck paragangliomas (HNPGLs): A single centre retrospective study.

CONTEXT: Head and neck paragangliomas (HNPGLs) are rare, usually benign, slow-growing tumours arising from neural crest-derived tissue. Definitive management pathways for HNPGLs have yet to be clearly defined. OBJECTIVE: To review our experience of the clinical features and management of these tumours and to analyse outcomes of different treatment modalities. METHODS: Demographic and clinical data were obtained from The Northern Ireland Electronic Care Record (NIECR) as well from a prospectively maintained HNPGL database between January 2011 through December 2023. RESULTS: There were 87 patients; 50 females: 37 males with a mean age of 52.3 ± 14.2 years old (range 17-91 years old). 58.6% (n = 51) of patients had carotid body tumours, 25.2% (n = 22) glomus vagal tumours, 6.8% (n = 6) tumours in the middle ear, 2.2% (n = 2) in the parapharyngeal space and 1.1% (n = 1) in the sphenoid sinus. 5.7% (n = 5) of patients had multifocal disease. The mean tumour size at presentation was 3.2 ± 1.4 cm (range 0.5-6.9 cm). Pathogenic SDHD mutations were identified in 41.3% (n = 36), SDHB in 12.6% (n = 11), SDHC in 2.2% (n = 2) and SDHA in 1.1% (n = 1) of the patients. Overall treatment modalities included surgery alone in 51.7% (n = 45) of patients, radiotherapy in 14.9% (n = 13), observation in 28.7% (n = 25), and somatostatin analogue therapy with octreotide in 4.5% (n = 4) of patients. Factors associated with a significantly higher risk of recurrence included age over 60 years (p = .04), tumour size exceeding 2 cm (p = .03), positive SDHx variants (p = .01), and vagal and jugular tumours (p = .04). CONCLUSION: The majority of our patients underwent initial surgical intervention and achieved disease stability. Our results suggest that carefully selected asymptomatic or medically unfit patients can be safely observed provided lifelong surveillance is maintained. We advocate for the establishment of a UK and Ireland national HNPGL registry, to delineate optimal management strategies for these rare tumours and improve long term outcomes.

Cervical Gastric-type Adenosquamous Carcinoma: Case Report of a Rare Neoplasm Associated With a BRCA1 Pathogenic Variant.

Gastric-type adenocarcinoma is the commonest human papillomavirus (HPV)-independent adenocarcinoma of the cervix. We report a rare case of a primary cervical gastric-type adenocarcinoma with malignant squamous elements (gastric-type adenosquamous carcinoma) in a 64-yr-old female. This is only the third report of a cervical gastric-type adenosquamous carcinoma. The tumor was p16 negative and molecular studies for HPV were negative. Next-generation sequencing showed pathogenic variants in BRCA1 and KRAS , as well as variants of unknown significance in CDK12 and ATM and homozygous deletion of CDKN2A/CDKN2B . Pathologists should be aware that not all cervical adenosquamous carcinomas are HPV-associated and the term gastric-type adenosquamous carcinoma is recommended when malignant squamous elements are present within a gastric-type adenocarcinoma. In reporting this case, we discuss the differential and the possible therapeutic options raised by the presence of pathogenic variants in BRCA1 .

WT1 Positive Ovarian Endometrioid Tumors: Observations From Consult Cases and Strategies for Distinguishing From Serous Neoplasms.

Ovarian endometrioid carcinoma, more than any other type of ovarian epithelial malignancy, demonstrates a varied morphology which can cause problems in diagnosis. In tubo-ovarian tumor pathology, WT1 is a commonly used marker as it is consistently expressed in low-grade and high-grade serous carcinomas and is often considered a specific marker of a serous phenotype. However, ovarian endometrioid neoplasms may also express WT1 which may contribute to misdiagnosis. We report our experience with 23 ovarian endometrioid neoplasms (4 borderline tumors, 19 carcinomas), mainly received in consultation, which were WT1 positive (diffuse in 11 cases) which often contributed to misdiagnosis. Endometriosis was identified in the same ovary in 6 cases and squamous elements in 7. We describe strategies for distinguishing such neoplasms, which may exhibit morphologic overlap with serous tumors, from low-grade and high-grade serous carcinomas and stress that a diagnosis of HGSC is unlikely with two grossly and histologically normal fallopian tubes. We also stress that a panel of markers should always be used rather than relying on a single marker and that when the morphology is classical of an endometrioid carcinoma, diagnostic immunohistochemistry is not needed given the potential for confusion in cases showing "aberrant" staining. We also discuss the phenomenon of "aberrant" immunohistochemical staining in endometrioid carcinomas which appears more common than in other ovarian carcinomas.

Bronchus-like Structures in Ovarian Teratomas: Report of a Series of a Previously Unreported Phenomenon With Potential For Misdiagnosis.

We report 10 cases of a previously undescribed lesion within ovarian teratomas which we designate bronchus-like structures. The lesions occurred in patients aged 16 to 56 yr (mean: 36) and involved the left ovary (n=5) or right ovary (n=5). Nine cases were mature teratomas (dermoid cysts/mature cystic teratomas or mature solid teratomas), 1 with somatic malignant transformation, and 1 was an immature teratoma. The bronchus-like structures ranged in size from 2.5 to 10 mm and were unifocal (7 cases) or multifocal (3 cases). The morphology was relatively constant in all cases and characterised by a well-formed bronchus surrounded by glandular structures, some of which were dilated, separated by stroma containing a variable amount of smooth muscle. In all but 1 case, a proportion of the glands contained abundant foamy cytoplasm. There was little or no nuclear atypia or mitotic activity. At low-power, the glands often had a somewhat "infiltrative" appearance and one case was originally diagnosed as a "pulmonary-type" adenocarcinoma arising in a dermoid cyst. In all cases, there was diffuse staining of the bronchus and glands with TTF1 and Napsin A, confirming the cell lineage. Follow-up in 4 cases (18-130 mo; median: 64 mo) showed no evidence of recurrence; 1 patient died from an unrelated malignancy. In reporting this apparently rare but possibly underrecognized benign lesion arising within ovarian teratomas, we discuss the differential diagnosis and stress that pathologists should be aware of this phenomenon in order to avoid an erroneous diagnosis of malignancy.

Ganglioneuroblastoma Arising in an Ovarian Dermoid Cyst: First Report in the Literature.

The development of a somatic neoplasm within an ovarian dermoid cyst (mature cystic teratoma) is a rare, but well described, phenomenon which occurs in approximately 1% of all cases. Any of the tissue components of a dermoid cyst has the potential to undergo neoplastic transformation with carcinoid tumors and squamous cell carcinomas being among the most common neoplasms. We report a case of a ganglioneuroblastoma arising within an ovarian dermoid cyst, an association which, as far as we are aware, has not been described previously.

Assessing the frequency of CD163+ tumor-associated macrophages and CD3+ T lymphocytes between MGUS and plasma cell myeloma.

Plasma cell dyscrasias (PCDs) are a heterogeneous group of diseases, and the most common is monoclonal gammopathy of undetermined significance (MGUS). This premalignant PCD consistently precedes multiple myeloma (MM), with a 1% risk of progression per year. Evading and suppressing the host immune system is an important step in the progression of MGUS to MM. This pilot study was designed to assess whether MGUS and MM have a distinct microenvironment, characterized by a unique distribution of immune cells, including tumor-associated macrophages. Evaluation of bone marrow (BM) tumor microenvironment was performed using immunohistochemical quantification of T cells (CD3), macrophages (CD68), and a macrophage subtype (CD163). The findings were compared between MGUS and MM to determine whether differences existed. The results suggest that there is a significantly lower percentage of CD3-positive, CD68-positive and CD163-positive immune effector cells in BM trephine biopsy samples from patients with MGUS than in those from patients with untreated MM (p < 0.001). Interestingly, in a patient treated for MM, the percentages of CD3+ and CD68+ cells were the same as those in other patients with untreated MM; however, the percentage of CD163+ cells reduced and correlated with low plasma cell count. Future studies are required to investigate whether the percentage of CD163+ cells is correlated with disease burden in patients with MM. If this is the case, then the level of soluble CD163 in plasma could be a potential biomarker of disease burden in patients with nonsecretory myelomas, in whom measurements of levels of paraprotein and free light chains are inconclusive.

Control and augmentation of long-term plasmid transgene expression in vivo in murine muscle tissue and ex vivo in patient mesenchymal tissue.

PURPOSE: In vivo gene therapy directed at tissues of mesenchymal origin could potentially augment healing. We aimed to assess the duration and magnitude of transene expression in vivo in mice and ex vivo in human tissues. METHODS: Using bioluminescence imaging, plasmid and adenoviral vector-based transgene expression in murine quadriceps in vivo was examined. Temporal control was assessed using a doxycycline-inducible system. An ex vivo model was developed and optimised using murine tissue, and applied in ex vivo human tissue. RESULTS: In vivo plasmid-based transgene expression did not silence in murine muscle, unlike in liver. Although maximum luciferase expression was higher in muscle with adenoviral delivery compared with plasmid, expression reduced over time. The inducible promoter cassette successfully regulated gene expression with maximum levels a factor of 11 greater than baseline. Expression was re-induced to a similar level on a temporal basis. Luciferase expression was readily detected ex vivo in human muscle and tendon. CONCLUSIONS: Plasmid constructs resulted in long-term in vivo gene expression in skeletal muscle, in a controllable fashion utilising an inducible promoter in combination with oral agents. Successful plasmid gene transfection in human ex vivo mesenchymal tissue was demonstrated for the first time.

Induction of effective antitumor response after mucosal bacterial vector mediated DNA vaccination with endogenous prostate cancer specific antigen.

PURPOSE: The induction of systemic immune responses against antigenic targets that are over expressed by cancer cells represents a powerful therapeutic strategy to target metastatic cancer. We generated specific antitumor immune responses in a murine model of prostate cancer by oral administration of an attenuated strain of Salmonella typhimurium containing a plasmid coding for murine prostate stem cell antigen. MATERIALS AND METHODS: Trafficking of S. typhimurium SL7207 in the initial 10 hours after gavage feeding was determined using a bacterial lux expressing strain and live bioluminescence imaging. For vaccination trials male C57 BL/6 mice were gavage fed SL7207/murine prostate stem cell antigen expressing plasmid or controls twice at 2-week intervals. One week after the last feeding the mice were challenged subcutaneously with TRAMPC1 murine prostate carcinoma cells. Tumor dynamics and animal survival were recorded. RESULTS: Clearance of bacterial vector from animals was complete 9 hours after feeding. Delivery of vector transformed with a firefly luciferase reporter plasmid resulted in maximal eukaryotic reporter gene expression in splenocytes 48 hours after feeding. Induction of tumor protective immunity was achieved by feeding the mice murine prostate stem cell antigen expressing plasmid bearing bacteria and greater than 50% of immunized mice remained tumor free. No significant toxicity was observed. Induction of T-helper type 1 immune responses was determined by measuring interferon-γ produced by splenocytes from vaccinated mice. When adoptively transferred to naive animals, splenocytes from vaccinated mice prevented tumor growth in 66% of challenged animals. CONCLUSIONS: Endogenous prostate cancer antigen gene delivery using a bacterial vector resulted in breaking immune tolerance to murine prostate stem cell antigen and significant retardation of tumor growth.

Orally administered bifidobacteria as vehicles for delivery of agents to systemic tumors.

Certain bacteria have emerged as biological gene vectors with natural tumor specificity, capable of specifically delivering genes or gene products to the tumor environment when intravenously (i.v.) administered to rodent models. We show for the first time that oral administration of bacteria to mice resulted in their translocation from the gastrointestinal tract (GIT) with subsequent homing to and replication specifically in tumors. The commensal, nonpathogenic Bifidobacterium breve UCC2003 harboring a plasmid expressing lux fed to mice bearing subcutaneous (s.c.) tumors were readily detected specifically in tumors, by live whole-body imaging, at levels similar to i.v. administration. Reporter gene expression was visible for >2 weeks in tumors. Mice remained healthy throughout experiments. Cytokine analyses indicated a significant upregulation of interferon-gamma (IFN-gamma) in the GIT of bifidobacteria-fed mice, which is associated with increases in epithelial permeability. However, B. breve feeding did not increase systemic levels of other commensal bacteria. The presence of tumor was not necessary for translocation to systemic organs to occur. These findings indicate potential for safe and efficient gene-based treatment and/or detection of tumors via ingestion of nonpathogenic bacteria expressing therapeutic or reporter genes.

HistoClean: Open-source software for histological image pre-processing and augmentation to improve development of robust convolutional neural networks.

The growth of digital pathology over the past decade has opened new research pathways and insights in cancer prediction and prognosis. In particular, there has been a surge in deep learning and computer vision techniques to analyse digital images. Common practice in this area is to use image pre-processing and augmentation to prevent bias and overfitting, creating a more robust deep learning model. This generally requires consultation of documentation for multiple coding libraries, as well as trial and error to ensure that the techniques used on the images are appropriate. Herein we introduce HistoClean; a user-friendly, graphical user interface that brings together multiple image processing modules into one easy to use toolkit. HistoClean is an application that aims to help bridge the knowledge gap between pathologists, biomedical scientists and computer scientists by providing transparent image augmentation and pre-processing techniques which can be applied without prior coding knowledge. In this study, we utilise HistoClean to pre-process images for a simple convolutional neural network used to detect stromal maturity, improving the accuracy of the model at a tile, region of interest, and patient level. This study demonstrates how HistoClean can be used to improve a standard deep learning workflow via classical image augmentation and pre-processing techniques, even with a relatively simple convolutional neural network architecture. HistoClean is free and open-source and can be downloaded from the Github repository here: https://github.com/HistoCleanQUB/HistoClean.

Anti-metastatic effects of viral and non-viral mediated Nk4 delivery to tumours.

The most common cause of death of cancer sufferers is through the occurrence of metastases. The metastatic behaviour of tumour cells is regulated by extracellular growth factors such as hepatocyte growth factor (HGF), a ligand for the c-Met receptor tyrosine kinase, and aberrant expression/activation of the c-Met receptor is closely associated with metastatic progression. Nk4 (also known as Interleukin (IL)32b) is a competitive antagonist of the HGF c-Met system and inhibits c-Met signalling and tumour metastasis. Nk4 has an additional anti-angiogenic activity independent of its HGF-antagonist function. Angiogenesis-inhibitory as well as cancer-specific apoptosis inducing effects make the Nk4 sequence an attractive candidate for gene therapy of cancer. This study investigates the inhibition of tumour metastasis by gene therapy mediated production of Nk4 by the primary tumour. Optimal delivery of anti-cancer genes is vital in order to achieve the highest therapeutic responses. Non-viral plasmid delivery methods have the advantage of safety and ease of production, providing immediate transgene expression, albeit short-lived in most tumours. Sustained presence of anti-angiogenic molecules is preferable with anti-angiogenic therapies, and the long-term expression mediated by Adeno-associated Virus (AAV) might represent a more appropriate delivery in this respect. However, the incubation time required by AAV vectors to reach appropriate gene expression levels hampers efficacy in many fast-growing murine tumour models. Here, we describe murine trials assessing the effects of Nk4 on the spontaneously metastatic Lewis Lung Carcinoma (LLC) model when delivered to primary tumour via plasmid lipofection or AAV2 vector. Intratumoural AAV-Nk4 administration produced the highest therapeutic response with significant reduction in both primary tumour growth and incidence of lung metastases. Plasmid-mediated therapy also significantly reduced metastatic growth, but with moderate reduction in primary subcutaneous tumour growth. Overall, this study demonstrates the potential for Nk4 gene therapy of metastatic tumours, when delivered by AAV or non-viral methods.

Antegrade deligation of iatrogenic distal ureteric obstruction utilising a high pressure balloon dilatation technique.

BACKGROUND: Iatrogenic trauma is the leading cause of ureteric injury with an incidence in abdominal and pelvic surgery varying between 0.4 and 2.5%. CASE: We report a case of ureteric obstruction caused by a haemostatic clip. There was associated rupture of the ureter proximal to the clip with intra-peritoneal leakage of urine. The patient was unfit for surgery and was managed by a novel procedure of endoluminal balloon deligation. CONCLUSION: Ureteric injuries are rare but potentially serious complications. They require prompt diagnosis and management depends on the patients' clinical condition, extent of injury and interval from injury to diagnosis. We have successfully demonstrated a new technique to treat ureteric obstruction caused by a haemostatic clip with associated ureteral rupture in a patient unfit for surgery.

Fallopian Tube Mucosal Involvement in Cervical Gastric-type Adenocarcinomas: Report of a Series With Discussion of the Distinction From Synchronous In Situ Tubal Lesions.

Cervical gastric-type adenocarcinomas are aggressive non-human papillomavirus-related carcinomas with a propensity for extracervical spread, including unusual sites such as the omentum, peritoneum, and ovary. We report 7 cases of cervical gastric-type adenocarcinoma with fallopian tube involvement predominantly in the form of mucosal colonization without underlying invasion. As far as we are aware, this has not been previously described and this report adds to the literature regarding metastatic neoplasms, which may exhibit tubal mucosal involvement and mimic an in situ lesion at this site. In all cases, there was associated ovarian involvement and in 6 of 7 cases, there was endometrial colonization. We speculate that the fallopian tube (and ovarian) involvement is secondary to transuterine spread. Given the occasional occurrence of multifocal gastric-type glandular lesions (benign or malignant) involving different sites in the female genital tract, we discuss the distinction between synchronous independent and metastatic lesions.

Kelly procedure for male primary epispadias.

INTRODUCTION: Primary epispadias is a rare congenital malformation involving the urogenital system. In patients with epispadias, bladder closure enhances bladder growth and continence. METHODS: Several steps were carried out to bring the bladder neck to the midline and allow tension-free bladder neck reconstruction and recreation of the natural angulation of urethra. The urethral plate and penile shaft were dissected and the corpora cavernosa separated, and then the bladder neck repair was performed. The urethral plate was tubularised and brought ventrally. The separated corpora were reapposed, avoiding torsion. The skin was reoriented to provide cover to the penis. RESULTS: The Kelly procedure improves cosmesis and continence by reconstructing a tension-free bladder neck repair and lengthening the penis. CONCLUSION: The video demonstrates the Kelly procedure for primary epispadias in a male child.

High-flow priapism following perineal trauma in a child.

Priapism is a rare condition in children and can be classified as high or low flow. We present a case of traumatic high-flow priapism that was successfully managed by selective embolisation of a branch of the internal pudendal artery. The pertinent clinical features are antecedent trauma and prolonged painless partial erection. The investigation of choice is Doppler ultrasound. Management can either be conservative, radiological or surgical. While conservative management can be safely attempted for 6 weeks, given the nature of the condition, early intervention is often required. Radiological embolisation is the first line and is successful in 97% of cases. Surgery carries a higher morbidity and is only reserved in cases where repeated embolisation has failed. This case highlights the importance of a thorough history and careful interpretation of imaging with protocolised follow-up of patients by a paediatric urologist for early and accurate diagnosis of erectile dysfunction and prompt intervention to prevent future complications.

Lithium Modulates Autophagy in Esophageal and Colorectal Cancer Cells and Enhances the Efficacy of Therapeutic Agents In Vitro and In Vivo.

Many epithelial cancers, particularly gastrointestinal tract cancers, remain poor prognosis diseases, due to resistance to cytotoxic therapy and local or metastatic recurrence. We have previously shown that apoptosis incompetent esophageal cancer cells induce autophagy in response to chemotherapeutic agents and this can facilitate their recovery. However, known pharmacological inhibitors of autophagy could not enhance cytotoxicity. In this study, we have examined two well known, clinically approved autophagy inducers, rapamycin and lithium, for their effects on chemosensitivity in apoptosis incompetent cancer cells. Both lithium and rapamycin were shown to induce autophagosomes in esophageal and colorectal cancer cells by western blot analysis of LC3 isoforms, morphology and FACS quantitation of Cyto-ID or mCherry-GFP-LC3. Analysis of autophagic flux indicates inefficient autophagosome processing in lithium treated cells, whereas rapamycin treated cells showed efficient flux. Viability and recovery was assessed by clonogenic assays. When combined with the chemotherapeutic agent 5-fluorouracil, rapamycin was protective. In contrast, lithium showed strong enhancement of non-apoptotic cell death. The combination of lithium with 5-fluorouracil or oxaliplatin was then tested in the syngenic mouse (balb/c) colorectal cancer model--CT26. When either chemotherapeutic agent was combined with lithium a significant reduction in tumor volume was achieved. In addition, survival was dramatically increased in the combination group (p < 0.0001), with > 50% of animals achieving long term cure without re-occurrence (> 1 year tumor free). Thus, combination treatment with lithium can substantially improve the efficacy of chemotherapeutic agents in apoptosis deficient cancer cells. Induction of compromised autophagy may contribute to this cytotoxicity.

Adenovirus-mediated transcriptional targeting of colorectal cancer and effects on treatment-resistant hypoxic cells.

BACKGROUND: Colorectal cancer is the second leading cause of cancer-related mortality and frequently presents with locally advanced or metastatic disease. Adenovirus (Ad) vectors are important gene delivery agents because they offer efficient and broad tissue transduceability. However, their ability to penetrate through multicell layers in colorectal cancers and maintain expression in colon tumor-related hypoxic conditions has yet to be analyzed. Furthermore, their broad tissue tropism presents safety concerns. MATERIALS AND METHODS: An ex vivo cultured patient tumor sample model was employed to examine Ad transduction of colorectal tumors. RESULTS: Results obtained from Ad delivery of the firefly luciferase (FLuc) reporter gene indicated that colon tumor tissue was more amenable to Ad transduction than other tumor histologic types examined (breast and ovary). Ad transduction levels were significantly higher than a range of viral and nonviral methods examined in patient colon tissue. Control of transgene expression using the CXC chemokine receptor 4 (CXCR4) promoter was examined as a strategy to confine expression to tumor cells. An Ad construct carrying FLuc under the control of the human CXCR4 promoter demonstrated low reporter gene expression compared with the ubiquitously expressing cytomegalovirus promoter in normal colon and liver tissue while providing high expression in tumors, demonstrating a 'tumour-on' and 'normal-off' phenotype in patient tissue. The effects of changing hypoxia on Ad-related transgene expression were examined in an in vitro model of hypoxic conditions relevant to clinical colorectal tumors. Reporter gene expression varied depending on the level of hypoxia, with significantly reduced levels observed with prolonged hypoxia. However, transgene expression was robust in the cycling hypoxic conditions relevant to colorectal tumors. CONCLUSION: This study provides novel, clinically relevant data demonstrating the potential for efficient gene delivery to colorectal tumors using Ad.

Targeting of breast metastases using a viral gene vector with tumour-selective transcription.

BACKGROUND: Adeno-associated virus (AAV) vectors have significant potential as gene delivery vectors for cancer gene therapy. However, broad AAV2 tissue tropism results in nonspecific gene expression. MATERIALS AND METHODS: We investigated use of the C-X-C chemokine receptor type 4 (CXCR4) promoter to restrict AAV expression to tumour cells, in subcutaneous MCF-7 xenograft mouse models of breast cancer and in patient samples, using bioluminescent imaging and flow cytometric analysis. RESULTS: Higher transgene expression levels were observed in subcutaneous MCF-7 tumours relative to normal tissue (muscle) using the CXCR4 promoter, unlike a ubiquitously expressing Cytomegalovirus promoter construct, with preferential AAVCXCR4 expression in epithelial tumour and CXCR4-positive cells. Transgene expression following intravenously administered AAVCXCR4 in a model of liver metastasis was detected specifically in livers of tumour bearing mice. Ex vivo analysis using patient samples also demonstrated higher AAVCXCR4 expression in tumour compared with normal liver tissue. CONCLUSION: This study demonstrates for the first time, the potential for systemic administration of AAV2 vector for tumour-selective gene therapy.

Preclinical evaluation of gene delivery methods for the treatment of loco-regional disease in breast cancer.

Preclinical results with various gene therapy strategies indicate significant potential for new cancer treatments. However, many therapeutics fail at clinical trial, often due to differences in tissue physiology between animal models and humans, and tumor phenotype variation. Clinical data relevant to treatment strategies may be generated prior to clinical trial through experimentation using intact patient tissue ex vivo. We developed a novel tumor slice model culture system that is universally applicable to gene delivery methods, using a realtime luminescence detection method to assess gene delivery. Methods investigated include viruses (adenovirus [Ad] and adeno-associated virus), lipofection, ultrasound (US), electroporation and naked DNA. Viability and tumor populations within the slices were well maintained for seven days, and gene delivery was qualitatively and quantitatively examinable for all vectors. Ad was the most efficient gene delivery vector with transduction efficiency >50%. US proved the optimal non-viral gene delivery method in human tumor slices. The nature of the ex vivo culture system permitted examination of specific elements. Parameters shown to diminish Ad gene delivery included blood, regions of low viability and secondary disease. US gene delivery was significantly reduced by blood and skin, while tissue hyperthermia improved gene delivery. US achieved improved efficacy for secondary disease. The ex vivo model was also suitable for examination of tissue-specific effects on vector expression, with Ad expression mediated by the CXCR4 promoter shown to provide a tumor selective advantage over the ubiquitously active cytomegalovirus promoter. In conclusion, this is the first study incorporating patient tissue models in comparing gene delivery from various vectors, providing knowledge on cell-type specificity and examining the crucial biological factors determining successful gene delivery. The results highlight the importance of in-depth preclinical assessment of novel therapeutics and may serve as a platform for further testing of current, novel gene delivery approaches.