Prognostic significance of immunohistochemical expression of VEGFR2 and iNOS in spinal chordoma.

PURPOSE: To clarify whether vascular endothelial growth factor receptor 2 (VEGFR2) and inducible nitric oxide synthase (iNOS) are involved in the angiogenesis and recurrence of spinal chordoma tissues and influence the overall survival. METHODS: All patients affected by a spinal chordoma surgically treated between 1986 and 2007 were reviewed. We examined the expression of VEGFR2 and iNOS with immunohistochemistry using a tissue microarray containing 120 chordoma samples. Local recurrence and overall survival (OS) were analyzed. RESULTS: A series of 40 chordoma patients who underwent surgery for a total of 120 lesions (including 80 recurrent lesions) were identified (sacrum 77.5 %, lumbar spine 17.5 %, cervical/thoracic spine 5 %). Surgical margins were wide in 30 (75 %), marginal in 8 (20 %) and intralesional in 2 (5 %) patients. Median follow-up was 120 months. The 5- and 10-year OS of the entire series of patients was 78.6 and 30 %, respectively. There were five primary chordomas (12.5 %) with moderate and 35 (87.5 %) with strong expression of VEGFR-2. All recurrent spinal chordomas displayed strong expression of VEGFR-2. The expression of iNOS was predominately moderate to high in primary chordomas: There were 15 tumors (37.5 %) with moderate and 25 tumors (62.5 %) with strong expression. All recurrent chordomas displayed strong expression of iNOS. CONCLUSION: The high expression of VEGFR-2 and iNOS affected the OS. The OS at 10 years was only 30 %.

Microscopic examination of iatrogenic subglottic tracheal stenosis: observations that may elucidate its histopathologic origin.

OBJECTIVES: The histopathologic origin of iatrogenic subglottic tracheal stenosis (ISTS) remains unclear. The purpose of this study was to use detailed operative microscopy to systematically examine the operative en bloc specimens of patients with ISTS and to observe the histologic and morphological changes in the hopes that these observations will provide insight into the histopathologic origin of these devastating injuries. METHODS: The operative specimens of 18 patients who underwent open tracheal or laryngotracheal resection for ISTS were examined. Precise morphological characteristics were investigated for each tissue layer, including the adventitia, the outer surface of the perichondrium, the cartilage, the inner surface of the perichondrium, the submucosa, and the mucosa. Each tissue layer was evaluated independently and in relationship to the other layers. The cartilaginous airway was further evaluated relative to the pars membranacea. RESULTS: The most common morphological finding in the epithelium was squamous metaplasia with occasional intense inflammation visible in the underlying mucosa, including cicatrization. The underlying cartilage demonstrated ossific metaplasia with sequestration in many cases. By far the most pronounced changes were found in the outer perichondrium and overlying adventitia and included diffuse paucicellular or hyperplastic fibrosis with intense hyperplastic scar formation or hyaline cicatrization. In the pars membranacea, severe scar formation and hyperplastic fibrosis were predominant. Ossific metaplasia was particularly severe in the lateral or outer parts of the tracheal ring, particularly in the vicinity of the adventitia and outer perichondrium. These changes were much more pronounced than the relatively minor changes observed in the submucosa and mucosa. CONCLUSIONS: The most severe pathologic observations occurred in the lateral tissue layers, ie, the outer perichondrium and adventia. Given that an injury occurs from the tracheal lumen, these tissue layers have the greatest distance from the site of injury. As only minor changes occurred in the inner tissue layers, we hypothesize that these tissues have a greater regenerative capacity than the outer layers. This study supports the theory that the depth of the airway injury is more critical to the development of ISTS than is the extent or length of the injury.

Expression of c-MET, low-molecular-weight cytokeratin, matrix metalloproteinases-1 and -2 in spinal chordoma.

AIMS: In skull base chordoma, c-MET expression has been reported to correlate with younger patient age and favourable prognosis; however, it also contributes to tumour invasiveness, especially in recurrent lesions, suggesting variable roles for c-MET according to clinical status. The aim of this study was to investigate the significance of c-MET expression in spinal chordoma, which affects patients who are 10-20 years older than those with skull base chordoma. METHODS AND RESULTS: Using immunohistochemical techniques, the expression of c-MET and its ligand, hepatocyte growth factor (HGF) was investigated in 34 primary spinal chordomas and compared with other clinicopathological parameters. Expression of c-MET and HGF was observed in 85.3 and 21.7% of lesions, respectively. c-MET expression correlated with the expression of an epithelial marker, low-molecular-weight cytokeratin (CAM5.2). Lesions with higher c-MET expression showed significantly stronger expression of proteinases, including matrix metalloproteinase (MMP)-1 and MMP-2. However, c-MET expression was not associated with patient age, proliferative ability estimated by MIB-1 labelling index, or prognosis. CONCLUSIONS: c-MET expression was observed in most spinal chordomas and correlated with the expression of CAM5.2, suggesting a relationship to an epithelial phenotype.

Expression of matrix metalloproteinases-1, -2, and -9; tissue inhibitors of matrix metalloproteinases-1 and -2; cathepsin B; urokinase plasminogen activator; and plasminogen activator inhibitor, type I in skull base chordoma.

Little is known about proteinase expression in skull base chordoma, a rare bone tumor exhibiting local invasiveness. Using immunohistochemical techniques, we investigated the expression of matrix metalloproteinases (MMPs)-1, -2, and -9; tissue inhibitors of matrix metalloproteinases (TIMPs)-1 and -2; cathepsin B (CatB); urokinase plasminogen activator (uPA); and plasminogen activator inhibitor, type I (PAI1), in 45 patients with skull base chordoma (45 primary and 25 autologous recurrent lesions). We compared these data with clinicopathologic parameters and the expression of cell differentiation markers. MMP-1, MMP-2, TIMP-1, CatB, uPA, and PAI1 were frequently expressed, and there was a significant correlation in the expression of some proteinases. Immunoreactivity for MMP-1, MMP-2, CatB, and uPA was significantly higher in lesions exhibiting tumor infiltration of host bone than in those without such components. Expression of MMP-1, TIMP-1, CatB, and uPA was associated with that of low-molecular-weight cytokeratin (CAM5.2). There were no differences in proteinase expression in 25 pairs of primary and their recurrent lesions, and proteinase expression did not predict local recurrences. However, patients with higher expression of both MMP-1 and uPA showed worse prognosis compared with the others. In conclusion, expression of some proteinases correlated with CAM5.2 expression and seemed to play an important role in a synergistic manner in the invasion process in skull base chordoma. The authors believe that elevated expression of MMP-1 and uPA can be used to identify patients with a worse prognosis in skull base chordoma.

Chordomas of the skull base: surgical management and outcome.

OBJECT: The goal of this study was to report on the surgical management of skull base chordomas and to evaluate both the short- and long-term treatment outcomes. METHODS: The authors retrospectively studied data from 49 patients who had undergone consecutive surgeries at a single institution. They also analyzed patterns of chordoma extension. Complications and surgery-related morbidity were recorded. A Kaplan-Meier analysis was performed to determine survival rates in patients 5 and 10 years after their first surgery. Operative approaches were selected on the basis of the predominant tumor extension. RESULTS: The approach used most frequently was the transethmoidal in 36.3%, followed by the pterional in 23.4% and the retrosigmoid in 23.4%. The tumor was totally removed in 49.4% and subtotally in 50.6%. The rate of total removal was highest at initial surgery (78%) and progressively declined thereafter. In 11.8% of cases a new neurological deficit developed, while the preoperative deficit remained unchanged. In 20% of cases the preoperative deficits improved, but new deficits also appeared. The 5- and 10-year survival rates are 65 and 39%, respectively. CONCLUSIONS: With an individually tailored surgical approach, total tumor removal in 78% of the cases was achieved at the initial surgery. Radical surgery appears to increase slightly the surgical morbidity, but at the same time prolongs the recurrence-free interval. Chordomas cannot be regarded as surgically curable tumors given the 5- and 10-year survival rates in patients harboring such lesions.

Molecular Diagnosis of Human Taenia martis Eye Infection.

Taenia martis, a tapeworm harbored in the intestine of mustelids, is a rarely encountered zoonotic cysticercosis pathogen. The larval stage closely resembles the Taenia solium cysticercus, but the natural host and thus the epidemiology of the disease is different. We here report a human eye infection diagnosed molecularly in a previously healthy female German patient. The case represents the third human infection described worldwide; the two previous cases were also European, involving eye and brain.

Is a synthetic augmentation in medial open wedge high tibial osteotomies superior to no augmentation in terms of bone-healing?

INTRODUCTION: Medial open-wedge high tibial osteotomy (MOWHTO) is an established method to treat unicompartimental osteoarthritis of the knee joint. However, augmentation of the created tibial gap after osteotomy is controversially discussed. METHODS: We performed a prospective investigation of 49 consecutive cases of MOWHTO at our department. Patients were divided into two groups: group A consisted of 19 patients while group B consisted of 30 patients. In group A, the augmentation of the opening gap after osteotomy was filled with a synthetic bone graft, whereas group B received no augmentation. As an indicator for bone healing we investigated the non-union rate in our study population and compared the non-union-rate between the two groups. RESULTS: The non-union rate was 28% in group A (five of 19 patients had to undergo revision) which received synthetic augmentation, while it was 3.3% in group B (one of 30 patients had to undergo revision) which received no augmentation. The difference between the groups was statistically significant (p-value 0.027). CONCLUSIONS: With regard to bone healing after MOWHTO, synthetic augmentation was not superior to no augmentation in terms of non-union rates after surgery. In fact, we registered a significantly higher rate of non-union after augmentation with synthetic bone graft. LEVEL OF EVIDENCE: III.

Intralesional fibrous septum in chordoma: a clinicopathologic and immunohistochemical study of 122 lesions.

Intralesional fibrous septum (IFS) generally is considered a reactive tissue in chordoma; however, little is known about its significance. We studied 122 chordomas for IFS using immunohistochemical techniques and compared IFS and lobular growth patterns (LGPs) formed by IFS with clinicopathologic parameters. Seventy-nine tumors (64.8%) revealed IFS. However, IFS frequently was infiltrated and interrupted by tumor cells with increased expression of proteases; only 33 (42%) of 79 tumors had LGP. In non-skull base chordomas, IFS and LGP were associated with nuclear pleomorphism, a previously described prognostic indicator, mitosis, and the MIB-1 labeling index, indicating a role of IFS and LGP in tumor growth or progression. Paradoxically, patients without LGP tended to have a worse prognosis than those with LGP. We believe that IFS exerts diverse influences on chordoma; however, invasion of IFS leading to loss of the LGP indicates advanced stages of tumor development, possibly predicting an unfavorable prognosis in chordoma.

Histogenesis of intralesional fibrous septum in chordoma.

Intralesional fibrous septum (IFS), a histologic architecture that is typical of chordoma, consists of proliferating spindle-shaped, fibroblast-like cells with an abundance of collagen fibers. However, the histogenesis of IFS is still controversial. In a series of 122 chordomas, special emphasis was placed on the morphology of host tissues involved in IFS and on a transition between IFS and neighboring tissues. In 23 lesions, IFS was also characterized both histochemically and immunohistochemically. IFS was observed in 79 (64.8%) lesions. Occasionally, IFS contained bone fragments and hyalinized matrix with no lining of osteoblastic cells, suggesting degenerated rather than metaplastic bone tissue. Moreover, IFS occasionally showed a direct transition to host bone trabeculae. Histochemically and immunohistochemically, IFS included calcium deposits positive for Alizarin red S staining and expressed both type I and type III collagen. In extraosseous lesions extending to the adjacent soft tissues, IFS frequently involved muscle fibers or peripheral nerve fibers and displayed a smooth transition to neighboring soft tissues. We believe that IFS is induced by a tumor-host interaction that is based on the host bone trabeculae in intraosseous lesions or on soft tissues in extraosseous lesions.

Expression of matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, cathepsin B, and urokinase plasminogen activator in non-skull base chordoma.

We analyzed the expression of proteases and the clinicopathologic significance in non-skull base chordoma (NSBC). By using immunohistochemical techniques, we studied the expression of matrix metalloproteinase (MMP)-1, MMP-2, MMP-9, cathepsin B (CatB), and urokinase plasminogen activator (uPA) in 29 NSBCs and compared these data with clinicopathologic parameters and the expression of cell differentiation markers. Expression of MMP-1 (P = .092), MMP-2 (P = .041), and CatB (P = .058) was associated with nuclear pleomorphism, a previously described adverse prognostic indicator. Expression of cytokeratin 8 correlated with that of MMP-1 (P = .005), MMP-2 (P = .002), and uPA (P = .032). Patients with higher MMP-2 expression had a poorer prognosis than those with lower MMP-2 expression (P = .013). We believe that NSBCs with nuclear pleomorphism or stronger epithelial character have a higher invasive ability than those without. In addition, high MMP-2 expression was an indicator of an unfavorable clinical outcome in NSBC.

Apoptosis, vascularity, and proliferation in primary central nervous system lymphomas (PCNSL): a histopathological study.

BACKGROUND: In the present study apoptosis, vascularity, and proliferation were quantitatively analyzed with immunohistopathological techniques in primary central nervous system lymphomas (PCNSL). Statistical analysis of these parameters was performed to evaluate their possible relationship with the unfavorable outcome of this tumor. METHODS: A series of 32 PCNSL patients for a total of 33 tumors treated from 1984 to 2000 in the Neurosurgical Department were reviewed, and their histologic specimens examined for apoptosis, vascularity, and proliferation. RESULTS: Patients were treated with either gross total/subtotal tumor removal or stereotactic biopsy. Vascularity was studied by means of FVIII staining, proliferative index with Ki-67 staining, and apoptosis with the TUNEL technique. Most tumors could be classified as immunoblastic or centroblastic B-Cell NHL. Mean Mib-1 Labeling Index was 35.34% (5-80), blood vessel density of 40.8 per 10 high power fields. Apoptotic cells were zero or less than 8 cells per 10 high power fields. CONCLUSION: No statistically significant correlation between survival and histopathological parameters could be shown. However, the apoptosis index was found to be negatively correlated with proliferative index and may account for a more aggressive clinical course of PCNSL.

Connection between expression of inducible nitric oxide synthase (iNOS) in skull base chordoma and lower urinary tract symptoms.

OBJECTIVE: To provide first insights into the potential role of iNOS expressed by skull base chordoma, which causes brainstem compression in and around Barrington's nucleus, and its effect on the micturition center. METHODS: Urodynamic testing of 22 symptomatic patients was performed. All women and men with skull base chordoma treated in two hospitals in Germany between 1986 and 2007 were studied. Lower urinary tract symptoms (LUTS) were documented in patients with acute brainstem compression due to local chordoma growth positive for iNOS expression. Brain magnetic resonance (MRI) images of the lesions of the symptomatic patients were performed. RESULTS: Of 74 treated patients, 22 (7 women, 15 men) with a median age of 37 years were evaluated with voiding diaries and computer urodynamic investigation. Urodynamic testing of 22 symptomatic patients with positive iNOS expression of skull base chordoma revealed detrusor overactivity in 55 %, low-compliance bladder in 14 %, detrusor sphincter dyssynergia in 45 % and uninhibited sphincter relaxation in 27 %. There was a significant correlation between strong iNOS expression (score 3-6) in skull base chordoma and severe urinary symptoms (p = 0.003, Spearman ρ = 0.526). CONCLUSIONS: The expression of iNOS in skull base chordoma compressing the dorsolateral pons, in and around Barrington's nucleus, may influence the pontine micturition center (PMC) and be responsible for lower urinary tract symptoms. Nitric oxide may possibly act as a neurotransmitter. We assume that the high infiltration of chordoma with monocyte/macrophages enhances the release of nitric oxide, as monocyte/macrophages are the main source of iNOS.

Expression of PDGFR-α, EGFR and c-MET in spinal chordoma: a series of 52 patients.

AIM: To investigate the expression of platelet-derived growth factor (PDGF) receptor-A (PDGFRα), epidermal growth factor receptor (EGFR) and c-Met in spinal chordoma. To the authors' knowledge, little is known regarding the prognostic significance of receptor tyrosine kinase in spinal chordoma. MATERIALS AND METHODS: Using immunohistochemical techniques, the authors investigated PDGFR-α, EGFR and c-MET expression in 52 primary and 104 recurrent lesions, and compared these data with clinicopathological parameters. RESULTS: PDGFR-α, EGFR and c-MET were found to be expressed in 75.0%, 83% and 77% of primary, and in 97.0% of recurrent lesions in all investigated receptor tyrosine kinases. Higher PDGFR-α and c-MET expression was found to be correlated with younger patient age. Lesions with a higher expression of PDGFR-α demonstrated significantly higher EGFR scores in both primary and recurrent lesions compared to those with lower PDGFR-α expression. In recurrent lesions, higher c-MET expression was found to be associated with significantly better prognosis than those with lower c-MET expression (p=0.033). Lesions with a higher level of PDGFR-α expression were found to have significantly poorer prognosis than those with lower PDGFR-α expression (p=0.024). Those patients with lower EGFR expression were found to have significantly better prognosis than those with higher EGFR expression (p=0.005). CONCLUSION: In the current study, c-MET expression in patients with spinal chordoma was found to be correlated with a younger patient age and a favorable prognosis. Patients with a higher level of PDGFR-α and EGFR expression were found to have a significantly poorer prognosis than those with lower PDGFR-α and EGFR expression.

Common molecular cytogenetic pathway in papillary tumors of the pineal region (PTPR).

Primary papillary tumors of the central nervous system and particularly the pineal region are rare. Papillary tumor of the pineal region (PTPR) is a recently described neoplasm that has been formally recognized in the 2007 World Health Organization Classification of Tumors of the Nervous System. Because of their rarity, further pheno- and genotypical observations as well as therapeutic experience are necessary to differentiate PTPR from other primary or secondary papillary tumors of this region. We herein present three cases of PTPR characterized by local recurrence in two of them. Primary and recurrent tumors were analyzed by immunohistochemistry and comparative genomic hybridization (CGH). From our results clonal chromosomal aberrations can be postulated which seem to be a feasible tool to differentiate PTPRs from other primary or secondary papillary tumors of this region.

Both epithelial cells and mesenchymal stem cell-derived chondrocytes contribute to the survival of tissue-engineered airway transplants in pigs.

OBJECTIVE: We sought to determine the relative contributions of epithelial cells and mesenchymal stem cell-derived chondrocytes to the survival of tissue-engineered airway transplants in pigs. METHODS: Nonimmunogenic tracheal matrices were obtained by using a detergent-enzymatic method. Major histocompatibility complex-unmatched animals (weighing 65 +/- 4 kg) were divided into 4 groups (each n = 5), and 6 cm of their tracheas were orthotopically replaced with decellularized matrix only (group I), decellularized matrix with autologous mesenchymal stem cell-derived chondrocytes externally (group II), decellularized matrix with autologous epithelial cells internally (group III), or decellularized matrix with both cell types (group IV). Autologous cells were recovered, cultured, and expanded. Mesenchymal stem cells were differentiated into chondrocytes by using growth factors. Both cell types were seeded simultaneously with a dual-chamber bioreactor. Animals were not immunosuppressed during the entire study. Biopsy specimens and blood samples were taken from recipients continuously, and animals were observed for a maximum of 60 days. RESULTS: Matrices were completely covered with both cell types within 72 hours. Survival of the pigs was significantly affected by group (P < .05; group I, 11 +/- 2 days; group II, 29 +/- 4 days; group III, 34 +/- 4 days; and group IV, 60 +/- 1 days). Cause of death was a combination of airway obstruction and infection (group I), mainly infection (group II), or primarily stenosis (group III). However, pigs in group IV were alive, with no signs of airway collapse or ischemia and healthy epithelium. There were no clinical, immunologic, or histologic signs of rejection despite the lack of immunosuppression. CONCLUSIONS: We confirm the clinical potential of autologous cell- and tissue-engineered tracheal grafts, and suggest that the seeding of both epithelial and mesenchymal stem cell-derived chondrocytes is necessary for optimal graft survival.

Structural and morphologic evaluation of a novel detergent-enzymatic tissue-engineered tracheal tubular matrix.

OBJECTIVE: We sought to bioengineer a nonimmunogenic tracheal tubular matrix of 6 cm in length and test its structural, functional, and immunologic properties in vitro and in vivo. METHODS: Twelve-centimeter tracheal segments were harvested from Yorkshire boars. Half of each segment was subjected to a detergent-enzymatic method (containing sodium deoxycholate/DNase lavations) of decellularization for as many cycles as needed, and the other half was stored in phosphate-buffered saline at 4 degrees C as a control. Bioengineered and control tracheas were then implanted in major histocompatibility complex-unmatched pigs (allograft) or mice (xenograft) heterotopically for 30 days. Structural and functional analysis and immunostaining were performed after each detergent-enzymatic method cycle and transplantation. RESULTS: Compared with control tracheas, bioengineered matrices displayed no major histocompatibility complex class I and II antigens after 17 detergent-enzymatic method cycles, without significant (P > .05) differences in their strain ability (rupture force, 56.1 +/- 3.3 vs 55.5 +/- 2.4 N; tissue deformation at 203% +/- 13% vs 200% +/- 8% or 12.2 +/- 0.8 vs 12 +/- 0.5 cm; and applied maximum force, 173.4 +/- 3.2 vs 171.5 +/- 4.6 N). Thirty days after implantation, significantly (P < .01) smaller inflammatory reactions (392 vs 15 macrophages/mm(2) and 874 vs 167 T lymphocytes/mm(2)) and P-selectin expressions (1/6 vs 6/6) were observed in both the xenograft and allograft models with bioengineered matrices compared with those seen with control tracheas. There was no development of anti-pig leukocyte antigen antibodies or increase in both IgM and IgG content in mice implanted with bioengineered tracheas. CONCLUSIONS: Bioengineered tracheal matrices displayed similar structural and mechanical characteristics to native tracheas and excite no immune response to 30 days when implanted as allografts or xenografts. This method holds great promise for the future of tissue-engineered airway replacement.

An experimental animal model of postobstructive pulmonary hypertension.

BACKGROUND: A small experimental animal model of postobstructive pulmonary hypertension (PH) providing insights in the physiopathology of this disease was developed. MATERIALS AND METHODS: Male Lewis rats were anesthetized and aleatory manipulated via a left thoracotomy with (group I, n = 10) or without (group II, n = 10) ligation of the left pulmonary artery. Animals were followed for 2 weeks and then sacrificed. Hemodynamic parameters and blood gases were recorded at baseline and 2 weeks after surgical procedure. RESULTS: Group I animals developed a significant (P < 0.01) PH (mean pulmonary artery pressure, 32 +/- 6 versus 16 +/- 2 mm Hg; pulmonary vascular resistance, 46 +/- 3 versus 21 +/- 2 mm Hg/mL/min; reduction of cardiac output, 75 +/- 3 versus 105 +/- 4 mL/min), compared to group II animals, and had a significant (P < 0.01) worse gas exchange (partial arterial pressure of O(2): 91 +/- 3 versus 439 +/- 24 mm Hg; partial arterial pressure of CO(2): 54 +/- 3 versus 42 +/- 2 mm Hg, on a fraction of inspired oxygen of 1.0), right ventricle hypertrophy (ventricle to left ventricle/septum ratio, 0.56 +/- 0.04 versus 0.45 +/- 0.04, P < 0.02) and less tolerance test (immobility time, 123 +/- 11 versus 61 +/- 8 s, P < 0.01) than group II animals. Histologically, ligated lungs showed postobstructive pulmonary vasculopathic abnormalities and bronchial-pulmonary artery hypertrophy, and the contralateral lung had initial signs of small vessel arteriopathy. CONCLUSIONS: The experimental model generated here successfully reproduced a PH morphologically and functionally similar to clinical postembolic PH and might be used for evaluating the physiopathology of postobstructive PH.