Does the Pittsburgh Severity Score predict outcome in esophageal perforation?

Esophageal perforation is an uncommon and challenging surgical emergency associated with high rates of morbidity and mortality. At present, no consensus exists on optimal management of the condition. The Pittsburgh Severity Score (PSS) is a tool intended to stratify perforation severity and guide treatment. However, there is a paucity of literature examining the validity of the score or its application in a UK population. This study aims to validate the PSS and explore its use in stratifying patients with esophageal perforation into distinct subgroups with differential outcomes in an independent UK study population.All patients treated for esophageal perforation at Queen Elizabeth Hospital, Birmingham between September 2003 and October 2017 were included in this study. Cases were identified using a combination of ICD-10 and OPCS informatics search codes and prospective case collection. Data relating to the clinical presentation, diagnosis, management, and outcome of cases were recorded using a preformed data collection form. PSS predictive performance was assessed against five outcomes: rates of post-perforation and post-operative complications, in-hospital mortality, length of intensive care (ICU/HDU) stay, and total length of hospital stay.A total of 87 cases were identified, consisting of 48 (55%) iatrogenic perforations, 24 (28%) cases of spontaneous (Boerhaave's) perforation, and 15 perforations due to other etiologies (17%). Operative management was favored in this series, with 47% of all perforations being treated surgically. Overall in-hospital mortality was 13%, coupled with a median length of hospital stay of 24 days (interquartile range [IQR]: 12-49), of which a median of 2 days was spent in intensive care facilities (IQR: 0-14). A total of 46% of patients developed post-perforation complications, with 59% of the operatively managed cohort developing complications post-operatively.The PSS was not found to be significantly predictive of post-perforation complications (area under the ROC curve [AUROC]: 0.62, p = 0.053) or in-hospital mortality (AUROC: 0.69, p = 0.057) for the cohort as a whole. However, a subgroup analysis found the accuracy of the PSS to vary considerably by etiology, being significantly predictive of post-perforation complications within the subgroup of Boerhaave's perforations (AUROC: 0.86, p = 0.004).In conclusion, we found that the PSS has some utility in stratifying esophageal perforation severity and predicting specific patient outcomes. However, it appears to be of more value when applied to the subgroup of patients with Boerhaave's perforations.

Rectal cancer in young adults: a series of 102 patients at a tertiary care centre in India.

OBJECTIVE: Rectal cancer in young patients is uncommon. There is little information on rectal cancer in young adults in India. The aim of this study was to determine the relative incidence of rectal cancer in young patients in India and identify any differences in histological grade and pathological stage between younger and older cohorts. METHOD: All adult patients presenting at a tertiary colorectal unit with primary rectal adenocarcinoma between September 2003 and August 2007 were included. Patients were divided into two groups: 40 years and younger, and older than 40 years. Details regarding patient demographics, preoperative assessment, management and tumour grade and stage were obtained from a prospectively maintained database. RESULTS: One hundred and two of 287 patients (35.5%) were 40 or younger at presentation. Younger patients were more likely to present with less favourable histological features (52.0% vs 20.5% (P < 0.001)) and low rectal tumours (63.0% vs 50.0%) (P = 0.043), but were equally likely to undergo curative surgery compared to the older group (P = 0.629). Younger patients undergoing surgery had a higher pathological T stage (T0-2 18.9%, T3 62.3%, T4 19.7% vs 34.5%, 56.0%, 9.5%) (P = 0.027) and more advanced pathological N stage (N0 31.1%, N1 41.0%, N2 27.9% vs 53.4%, 26.7%, 17.2%) (P = 0.014). CONCLUSION: The relative number of young patients with rectal cancer in this Indian series is higher than figures reported in western populations. The reasons for this are not clear. The histopathological features of rectal tumours in young patients in this study are consistent with similar studies in Western populations.

Locally recurrent chondrosarcoma of the pelvis and limbs can only be controlled by wide local excision.

AIMS: The purpose of this study was to investigate the potential for achieving local and systemic control after local recurrence of a chondrosarcoma of bone. PATIENTS AND METHODS: A total of 126 patients with local recurrence (LR) of chondrosarcoma (CS) of the pelvis or a limb bone were identified from a prospectively maintained database, between 1990 and 2015 at the Royal Orthopaedic Hospital, Birmingham, United Kingdom. There were 44 female patients (35%) and 82 male patients (65%) with a mean age at the time of LR of 56 years (13 to 96). The 126 patients represented 24.3% of the total number of patients with a primary CS (519) who had been treated during this period. Clinical data collected at the time of primary tumour and LR included the site (appendicular, extremity, or pelvis); primary and LR tumour size (in centimetres); type of operation at the time of primary or LR (limb-salvage or amputation); surgical margin achieved at resection of the primary tumour and the LR; grade of the primary tumour and the LR; gender; age; and oncological outcomes, including local recurrence-free survival and disease-specific survival. A minimum two years' follow-up and complete histopathology records were available for all patients included in the study. RESULTS: For patients without metastases prior to or at the time of local recurrence, the disease-specific survival after local recurrence was 62.5% and 45.5% at one and five years, respectively. After univariable analysis, significant factors predicting disease-specific survival were grade (p < 0.001) and surgical margin (p = 0.044). After multivariable analysis, grade, increasing age at the time of diagnosis of local recurrence, and a greater time interval from primary surgery to local recurrence were significant factors for disease-specific survival. A secondary local recurrence was seen in 26% of patients. Wide margins were a good predictor of local recurrence-free survival for subsequent recurrences after univariable analysis when compared with intralesional margins (p = 0.002) but marginal margins did not reach statistical significance when compared with intralesional margins (p = 0.084). CONCLUSION: In cases of local recurrence of a chondrosarcoma of bone, we have shown that if the tumour is non-metastatic at re-staging, an increase in disease-specific survival and in local recurrence-free survival is achievable, but only by resection of the local recurrence with a wide margin. Cite this article: Bone Joint J 2019;101-B:266-271.

Minimising aseptic loosening in extreme bone resections: custom-made tumour endoprostheses with short medullary stems and extra-cortical plates.

AIMS: Following the resection of an extensive amount of bone in the treatment of a tumour, the residual segment may be insufficient to accept a standard length intramedullary cemented stem. Short-stemmed endoprostheses conceivably have an increased risk of aseptic loosening. Extra-cortical plates have been added to minimise this risk by supplementing fixation. The aim of this study was to investigate the survivorship of short-stemmed endoprostheses and extra-cortical plates. PATIENTS AND METHODS: The study involved 37 patients who underwent limb salvage surgery for a primary neoplasm of bone between 1998 and 2013. Endoprosthetic replacement involved the proximal humerus in nine, the proximal femur in nine, the distal femur in 13 and the proximal tibia in six patients. There were 12 primary (32%) and 25 revision procedures (68%). Implant survivorship was compared with matched controls. The amount of bone that was resected was > 70% of its length and statistically greater than the standard control group at each anatomical site. RESULTS: The mean follow-up was seven years (one to 17). The mean length of the stem was 33 mm (20 to 60) in the humerus and 79 mm (34 to 100) in the lower limb. Kaplan-Meier analysis of survival of the implant according to anatomical site confirmed that there was no statistically significant difference between the short-stemmed endoprostheses and the standard stemmed controls at the proximal humeral (p = 0.84), proximal femoral (p = 0.57), distal femoral (p = 0.21) and proximal tibial (p = 0.61) sites. In the short-stemmed group, no implants with extra-cortical plate osseointegration suffered loosening at a mean of 8.5 years (range 2 to 16 years). Three of ten (30%) without osseointegration suffered aseptic loosening at a mean of 7.7 years (range 2 to 11.5 years). CONCLUSION: When extensive resections of bone are required in the surgical management of tumours, and in revision cases, the addition of extra-cortical plates to short medullary stems has shown non-inferiority to standard length medullary stems and minimises aseptic failure. Cite this article: Bone Joint J 2017;99-B:1689-95.

Presence of two cytogenetic forms of amplified DNA: evidence for a role in tumor growth in an intraspecific mouse hybrid cell line.

An intraspecific mouse hybrid epithelial cell line, F5/B, is described in which the homogeneously staining region (HSR)-containing marker chromosome from one parent is absent in about half of the cells. It is replaced in these cells by double minutes (DM), an alternative form of amplified DNA, which is liable to loss because of its instability at mitosis. DM probably arise from the breakdown of the HSR during clonal growth of F5/B. Subclones were derived possessing one or another cytogenetic feature, and their cloning efficiency in vitro and tumorigenicity in syngeneic animals were compared. There were no differences in in vitro tumorigenicity, but in vivo DM-containing subclones were significantly less tumorigenic than HSR-containing subclones or the F5/B parent hybrid. In tumors that developed after long latent periods, cells had increased numbers of DM compared with the inoculated population, demonstrating a selective advantage in vivo for cells with a high DM content. These results indicate a role for the amplified DNA in tumor growth.

Chromosome changes associated with the progression of cell lines from preneoplastic to tumorigenic phenotype during transformation of mouse salivary gland epithelium in vitro.

Two mouse salivary gland epithelial cell lines, CSG 211 and CSG 205/2B1, isolated during carcinogen-induced neoplastic transformation in vitro, were analyzed cytogenetically before and after they acquired the ability to produce carcinomas in syngeneic animals. With the use of Giemsa banding techniques, chromosome changes were identified that were associated with the transition from a preneoplastic to a fully transformed (tumorigenic) phenotype during serial passage in vitro. Results were compared with those from a third cell line of similar origin, CSG 225, which was tumorigenic at the earliest passage tested. These cell lines were found to be subtetraploid, which confirms previous data, and the tumorigenic lines showed consistent losses of copies of chromosomes 1, 4, 7, 9, and 14. Compared with their preneoplastic counterparts, the loss of no single chromosome seems to be sufficient to generate the tumorigenic phenotype, but the loss of a combination of some or all of these chromosomes appears to be important in the phenotypic transition. In CSG 211 the loss of chromosome 7 is probably more important in this respect than loss of the other chromosomes listed. The karyotype of this cell line undergoes major structural rearrangement, which suggests that loss of specific regions of chromosomes 1 and 9 is also important.

Changes in DNA content during in vitro transformation of mouse salivary gland epithelium.

DNA content was measured in single cells in situ during the in vitro development of neoplastic transformation in epithelial cells from mouse salivary glands. The earliest change in DNA content was found in stage III of the transformation process (a preneoplastic stage). In foci of these cells, the percentage of tetraploid (4C) cells was 30--60% compared with the starting tissue and early primary cultures, which were diploid. The stage III foci eventually gave rise to subtetraploid tumorigenic cell lines. The studies suggested that during in vitro development of neoplastic transformation in salivary gland epithelium, tetraploids were generated that then underwent a period of chromosome instability and loss. Evidence was also presented that a similar mechanism may be operating in transformation of salivary gland epithelium in vivo. A possible mechanism for transformation on the basis of chromosome imbalance was discussed.

Different effects of a macrophage cytokine on proliferation in astrocytes and Schwann cells.

The proliferative response in vitro to a novel macrophage inflammatory protein (MIP) 1 alpha has been investigated in astrocytes and Schwann cells. MIP 1 alpha is growth-inhibitory in all cell systems investigated so far and we show here that this cytokine also inhibits the proliferation of astrocytes. This response is seen most clearly when MIP 1 alpha reduces the proliferative response of astrocytes to a potent mitogen. Elevation of intracellular cyclic AMP with forskolin enhances the effects of MIP 1 alpha. In contrast, we show that the proliferation of cultured Schwann cells is stimulated by MIP 1 alpha, and that stimulation is enhanced by simultaneous exposure to forskolin. The possible consequences of these differing responses are discussed in the context of the acute response to injury and potential for regeneration of the peripheral and central nervous systems.

Spontaneous orientation of transplanted olfactory glia influences axonal regeneration.

Transplanted olfactory ensheathing cells (OECs) have previously been demonstrated to support axonal growth and myelination in the adult rat CNS. Here, the capacity of donor OECs to control the direction of axonal regeneration has been investigated following transplantation, as elongated columns, into the thalamus of adult rats. The OECs formed a 'glial bridge' which extended from the thalamus to the hippocampus. Transplanted OECs rapidly adopted a spindle-shaped morphology which was orientated along the vertical axis of the transplant. Numerous host axons grew into the transplants and followed the highly orientated OEC cell matrix across the choroid fissure. Thus, the spontaneous elongation and orientation of donor OECs may support highly directional host axonal growth across natural barriers within the CNS.

Regeneration of adult rat retinal ganglion cell processes in monolayer culture: comparisons between cultures of adult and neonatal neurons.

The aim of the present study was to develop a model culture system for the study of factors controlling regeneration of axons from injured adult mammalian central nervous system. We show, for the first that retinal ganglion cells (RGC) dissociated from adult rat retina, regrow processes in vitro over long distances under over appropriate conditions in monolayer culture. Most importantly, adult RGC depend completely upon the presence of a preformed layer of neonatal cortical astrocytes, whereas RGC from neonatal retinae are supported by indigenous retinal glia which spread and proliferate to form a monolayer of cells upon which RGC regrow processes. Adult retinal glia fail to spread on the culture surface and proliferate in the same way and we suggest that this is a major factor in limiting the survival of adult RGC on an acellular substrate such as polylysine. Laminin does not substitute for the presence of a glial monolayer. These findings indicate that at least one type of adult CNS neuron is capable of regenerating its processes in vitro in an environment which includes a cellular component of CNS tissue.

Oligodendrocyte-type 2 astrocyte (O-2A) progenitor cells from neonatal and adult rat optic nerve differ in their responsiveness to platelet-derived growth factor.

We have investigated, in vitro, the mitogenic responsiveness to platelet-derived growth factor (PDGF) of oligodendrocyte-type 2 astrocyte (O-2A) progenitor cells isolated from adult rat optic nerve and their differentiation into oligodendrocytes. Progenitor cells from adult optic nerves differentiate into oligodendrocytes in a limiting concentration of foetal calf serum more slowly than in cultures of neonatal cells. Nevertheless, differentiation of oligodendrocytes from progenitors is nearly complete by 6 days in vitro, with 50% expressing galactocerebroside by 4-5 days. In these experiments, adult optic nerve cells were grown in medium containing PDGF, a potent mitogen for neonatal O-2A progenitor cells, and yet the decline in numbers of O-2A progenitor cells matches the rise in oligodendrocyte numbers. We suggest that this is because adult O-2A progenitor cells differ from their neonatal counterparts and do not show the same proliferative response in the presence of exogenous PDGF. We tested this hypothesis by a quantitative autoradiographic analysis of tritiated thymidine-labelled nuclei, comparing percentages of labelled adult and neonatal O-2A lineage glial cells in low-serum medium, in the presence of absence of PDGF, with their response to a monolayer of neonatal rat cortical type 1 astrocytes or astrocyte-conditioned medium. Whereas, adult O-2A progenitors responded to astrocyte monolayers and to conditioned medium from astrocyte cultures, there was no dose-dependent response to PDGF-BB over a wide range of concentrations. Antibodies to human PDGF neutralise the growth-promoting activity of astrocyte-conditioned medium for neonatal O-2A cells but do not neutralise astrocyte-conditioned medium stimulation of adult O-2A progenitor cells. This indicates that the principal astrocyte-derived growth factor(s) for adult O-2A progenitor cells is unlikely to be PDGF.

The conditioning effect of optic nerve injury upon axonal regrowth from adult rat retinal ganglion cells explanted in vitro.

An in vitro assay was used to determine the effects of conditioning nerve lesions on the regeneration of adult rat retinal ganglion cell (RGC) axons from retinal explants. Following the conditioning lesion (CL) of unilateral optic nerve transection, maximal regrowth was seen from RGC explanted from ipsilateral retinae 10 days post-CL. Explants from this group initiated axonal regrowth earlier and a greater percentage regrew axons when compared with explants from normal rats. Axonal regrowth from explants of retinae contralateral to CL was also seen earlier than normal. In further experiments, the effects of both exposure of the optic nerve sheath in the orbit and the incision of the dura without injury to optic nerve axons were studied. The conditioning effect of a dural incision was found to be the same as that of optic nerve transection, whilst exposure of the optic nerve sheath had no conditioning effect on RGC axonal regrowth in vitro.

Cell-mediated mutagenesis in cultured Chinese hamster cells by carcinogenic polycyclic hydrocarbons: nature and extent of the associated hydrocarbon-DNA reaction.

A system of cell-mediated mutagenesis is described for the study of compounds which require metabolic activation to exert their cytotoxic and mutagenic effects. This system combines BHK21 cells for metabolism of the compounds and V79 cells as targets for mutagenesis. Using the two polycyclic hydrocarbon carcinogens benzo(a)pyrene and 7-methylbenz(a)anthracene we have shown that the hydrocarbon-DNA reaction which accompanies mutagenesis in the target cell is indistinguishable from that reported to occur in vivo and in primary cell cultures. Our results also support the view that a diol epoxide metabolite is responsible for the biological activity of benzo(a)pyrene. The application of cell-mediated mutagenesis to the routine testing of suspect environmental chemicals for biological activity is discussed.

TPA affects early and late stages of chemically-induced transformation in mouse submandibular salivary epithelial cells in vitro.

The tumor promoter, 12-O-tetradecanoyl-phorbol-13-acetate (TPA), is a potent mitogen in mouse submandibular epithelial cells in vitro. Effects of TPA were investigated on various stages in the transformation of this cell type by the carcinogen benzo[a]pyrene. There was no evidence of enhancement of the frequency of induction of foci of preneoplastic epithelial cells following a high, transforming dose of carcinogen, but TPA promoted this early stage in transformation if given at weekly intervals after a subthreshold, initiating exposure to carcinogen. Foci from all TPA-treated cultures appeared earlier and grew in size more rapidly than those induced by carcinogen alone. There was no evidence from these experiments, however, that foci from TPA-treated cultures were more likely to give rise to permanent epithelial cell lines or that these cell lines became tumorigenic earlier. Preliminary results showed that one out of two permanent, preneoplastic epithelial cell lines examined responded to the promoter at a late stage in transformation by showing enhanced tumorigenicity in syngeneic animals.

Salivary epithelial cells in primary culture: characterization of their growth and functional properties.

Mouse submandibular salivary gland cells were grown in primary explant culture. After an initial period of degeneration within the explant, surviving epithelial cells proliferated rapidly and duct-like structures recolonized the explant. Autoradiographic studies showed that a peak of DNA synthesis occurred after 4 days in vitro and that proliferation was enhanced by insulin and hydrocortisone. These cells retained specialized secretory function (protease activity) for at least 2 weeks in vitro. This enzyme is a differentiated product of granular tubule cells in vivo. Between 6 and 10 days, explants attached to the substrate. An outgrowth developed, consisting largely of ultrastructurally identifiable epithelial cells which formed pseudoglandular structures in the monolayer. Epithelium survived for over 6 months in primary culture but could not be serially transferred. Secondary cultures were rapidly overgrown by mesenchymal cells.

Different tumours induced by benzo(a)pyrene and its 7,8-dihydrodiol injected into adult mouse salivary gland.

A comparison has been made between the carcinogenic activities of benzo(a)pyrene and the proposed proximate carcinogen, benzo(a)pyrene 7,8-dihydrodiol, in the adult C57BL mouse submandibular salivary gland. In preliminary studies using a range of doses, the dihydrodiol was slightly less active than the parent hydrocarbon in this system. There was a difference in the type of tumour induced by the 2 compounds. Benzo(a)pyrene induced tumours of the salivary glands at the site of injection, whereas the dihydrodiol induced malignant lymphosarcomas, particularly of the thymus, which were often metastatic to other orgnas. Possible reasons for the different sites of action of the 2 compounds are discussed.

Elevated production of growth factor by human premalignant colon adenomas and a derived epithelial cell line.

Growth factor activity which stimulates anchorage-independent growth (AIG) in a rat fibroblast line, was detected in human premalignant adenoma tissue from familial polyposis coli colectomy specimens and in serum-free culture supernatant from an adenoma cell line PC/AA. The activity extracted from adenoma tissue was compared quantitatively in the AIG bioassay with extracts of normal mucosa from split thickness colorectal tissue. Adenoma tissue yielded three times the amount of acid-extractable protein g-1 wet wt and adenoma extracts consistently had significantly greater specific activity over a wide protein concentration range. Activity extracted from adenoma tissue and from the derived cell line PC/AA were compared qualitatively after fractionation by gel filtration. Both extracts showed almost identical profiles of biological activity after assay of individual fractions for AIG stimulation, suggesting that the factor(s) originates from the epithelial component of the adenoma tissue since PC/AA is a pure epithelial cell line. Activity eluted as two major peaks with apparent mol. wts of 9 kd and 20-25 kd (relative to standards) in both cases. This report demonstrates for the first time that elevated production of a growth factor may be an early change in the evolution of human colorectal cancer from small, premalignant adenomas.

Chronically denervated rat Schwann cells respond to GGF in vitro.

C-erbB receptor/neuregulin signalling plays a significant role in Schwann cell function. In vivo, Schwann cells up-regulate expression of c-erbB receptors in the first month after injury, but receptor expression is down-regulated with time to levels that are not detectable immunohistochemically. The inability of chronically denervated Schwann cells to respond adequately to signals derived from regenerating axons may be one reason why delayed repair of an injured peripheral nerve frequently fails. We have examined the effects of GGF on denervated Schwann cells in vitro. A modified delayed dissociation technique was used to obtain adult rat Schwann cells from the distal stumps of transected sciatic nerves which had been acutely (7 days) or chronically (2-6 month) denervated. We found that in vitro denervated Schwann cells invariably expressed p75NTR and c-erbB receptors. There was a progressive decrease in total cell yield and the percentage of cells with Schwann cell phenotype (p75NTR and/S-100 or/laminin or /GFAP or/c-erbB positive); proliferation rate; migratory potential; and expression of the cell adhesion molecules N-CAM and N-cadherin, with increasing time of denervation. Addition of GGF2 had a significant stimulatory effect upon Schwann cell proliferation and migration, and an increased proportion of Schwann cells expressed N-CAM and N-cadherin, suggesting that these responses were mediated via GGF/c-erbB signalling. Our results support the view that it may be possible to manipulate chronically denervated Schwann cells so that they become more responsive to signals derived from regrowing axons.

Spontaneous immortalisation of ensheathing cells from adult rat olfactory nerve.

In this report, we describe the isolation of a cell line, Rolf B1.T, from cultures of adult rat olfactory nerve cells. Rolf B1.T cells have an antigenic phenotype which closely resembles that of olfactory ensheathing cells. In routine culture conditions, Rolf B1.T cells constitutively express glial fibrillary acidic protein, S1OO, the low-affinity neurotrophin receptor p75 NGF, laminin, tenascin, and the neural cell adhesion molecule (N-CAM); a variable proportion of the cells also express cadherin, which is regulated by local culture conditions and is associated positively with cell proliferation status. We provide evidence that the association may be indirect and linked to a related parameter such as local cell density. Rolf B1.T cells arose from a population of less well-differentiated cells after a spontaneous immortalisation event. The cells retain many characteristics of normal cells, are dependent on serum growth factors for their proliferation, and fail to grow in semi-solid agar. Rolf B1.T cells support the regrowth of neurites from adult retinal ganglion cells in vitro in a heterologous co-culture system and will have potential value in investigations into the mechanisms of glial support for axonal regeneration from adult mammalian central neurons.

Neither laminin nor prior optic nerve section are essential for the regeneration of adult mammalian retinal ganglion cell axons in vitro.

Retinal explants obtained from normal adult rats and from operated animals in which the optic nerve had been sectioned 10 days previously were cultured in either serum-containing or serum-free medium on poly-L-lysine and laminin substrata. Regenerating ganglion cell axons growing from these explants have been identified using monoclonal antibodies against Thy-1.1 cell surface glycoprotein and the 200-kDa subunit neurofilament protein. Irrespective of substratum or medium composition, axons regenerated from 28-49% of normal rat retinal explants. This percentage increased to 60-84% of explants from operated rats. There were no significant differences in percentages of explants from normal or operated rats showing neurite outgrowth when substrata of either poly-L-lysine or laminin were compared in serum-free medium. In serum-containing medium the results were less easily interpreted due to the presence of an outgrowth of non-neuronal (glia and mesenchymal) 'flat cells', which served as a preferred axonal substratum in many cases. Thus we show that adult rat retinal ganglion cell axons will regrow in vitro, and that a 'priming' optic nerve section will increase this response. In neither case is the response laminin-dependent.