Antibiotic delivery from bone-targeted mesoporous silica nanoparticles for the treatment of osteomyelitis caused by methicillin-resistant Staphylococcus aureus

Osteomyelitis is a hard-to-treat infection of the bone and bone marrow that is mainly caused by Staphylococcus aureus, with an increasing incidence of methicillin-resistant S. aureus (MRSA). Owing to the aggressiveness of these bacteria in colonizing and destroying the bone, systemic antibiotic treatments fail to eradicate the infection. Instead, it normally entails surgery to remove the dead or infected bone. In this work, we report bone-targeted mesoporous silica nanoparticles for the treatment of osteomyelitis. The nanoparticles have been engineered with a functional gelatine/colistin coating able to hamper premature release from the mesopores while effectively disaggregating the bacterial biofilm. Because antibiotic resistance is a global emergency, we have designed two sets of identical nanoparticles, carrying each of them a clinically relevant antibiotic, that have demonstrated to have synergistic effect. The bone-targeted nanoparticles have been thoroughly evaluated in vitro and in vivo, obtaining a notable reduction of the amount of bacteria in the bone in just 24 h after only one dose, and paving the way for localized, nanoparticle-mediated treatment of MRSA-caused osteomyelitis. STATEMENT OF SIGNIFICANCE: In this work, we propose the use of bone-targeted mesoporous silica nanoparticles to address S. aureus-caused osteomyelitis that render synergistic therapeutic effect via multidrug delivery. Because the bacterial biofilm is responsible for an aggressive surgical approach and prolonged antibiotic treatment, the nanoparticles have been functionalized with a functional coating able to both disaggregate the biofilm, hamper premature antibiotic release and protect the intact bone. These engineered nanoparticles are able to effectively target bone tissue both in vitro and in vivo, showing high biocompatibility and elevated antibacterial effect.

Overcoming PLK1 inhibitor resistance by targeting mevalonate pathway to impair AXL-TWIST axis in colorectal cancer

New therapeutic targets are revolutionizing colorectal cancer clinical management, opening new horizons in metastatic patients' outcome. Polo Like Kinase1 (PLK1) inhibitors have high potential as antitumoral agents, however, the emergence of drug resistance is a major challenge for their use in clinical practice. Overcoming this challenge represents a hot topic in current drug discovery research. BI2536-resistant colorectal cancer cell lines HT29R, RKOR, SW837R and HCT116R, were generated in vitro and validated by IG50 assays and xenografts models by the T/C ratio. Exons 1 and 2 of PLK1 gene were sequenced by Sanger method. AXL pathway, Epithelial-to-Mesenchymal transition (EMT) and Multidrug Resistance (MDR1) were studied by qPCR and western blot in resistant cells. Simvastatin as a re-sensitizer drug was tested in vitro and the drug combination strategies were validated in vitro and in vivo. PLK1 gene mutation R136G was found for RKOR. AXL pathway trough TWIST1 transcription factor was identified as one of the mechanisms involved in HT29R, SW837R and HCT116R lines, inducing EMT and upregulation of MDR1. Simvastatin was able to impair the mechanisms activated by adaptive resistance and its combination with BI2536 re-sensitized resistant cells in vitro and in vivo. Targeting the mevalonate pathway contributes to re-sensitizing BI2536-resistant cells in vitro and in vivo, raising as a new strategy for the clinical management of PLK1 inhibitors.

Defining stage in mucinous tumours of the appendix with peritoneal dissemination: the importance of grading terminology: systematic review

Background

Mucinous appendiceal neoplasms with peritoneal dissemination (PD) show a wide spectrum of clinical behaviour. Histological grade has been correlated with prognosis, but no universally accepted histological grading has been established. The aim of this systematic review was to provide historical insight to understand current grading classifications, basic histopathological features of each category, and to define which classification correlates best with prognosis.

Methods

MEDLINE and the Cochrane Library were searched for studies that reported survival across different pathological grades in patients with mucinous neoplasm of the appendix with PD treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. PRISMA guidelines were followed.

Results

Thirty-eight studies were included. Ronnett’s classification was the most common (9 studies). Classifications proposed by the Peritoneal Surface Oncology Group International (PSOGI) (6 studies) and the seventh or eighth edition of the AJCC (7 studies) are gaining in popularity. Nine studies supported a two-tier, 12 a three-tier, and two a four-tier classification system. Three studies demonstrated that acellular mucin had a better prognosis than low-grade pseudomyxoma peritonei in the PSOGI classification or M1bG1 in the eighth edition of the AJCC classification. Four studies demonstrated that the presence of signet ring cells was associated with a worse outcome than high-grade pseudomyxoma peritonei in the PSOGI classification and M1bG2 in the eighth edition of the AJCC.

Conclusion

There is a great need for a common language in describing mucinous neoplasms of the appendix with PD. Evolution in terminology as a result of pathological insight turns the four-tiered PSOGI classification system into a coherent classification option.

Aryl hydrocarbon receptor interacting protein (AIP) significantly influences prognosis of pancreatic carcinoma

INTRODUCTION

Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor. Aryl hydrocarbon receptor interacting protein (AIP) in one of AHR ligands. The aim of this study is to analyze the prognostic influence of AIP in pancreatic carcinoma.

MATERIAL AND METHODS

Retrospective case series with immunohistochemical analysis of AIP. We have estimated a multivariate Cox's model for the outcome (progression free and overall survival).

RESULTS

204 patients were included in the study. As expected prognosis was poor and 67.8% died of disease. As for AIP 9.8% of the cases showed nuclear staining of the epithelial tumor cells and 59.4% a cytoplasmic one. Stroma was stained in 53.1% of the cases. Univariate survival analysis revealed a significantly worse prognosis of patients with cytoplasmic AIP expression (stroma and epithelium), but nuclear expression was associated to a better prognosis. In the multivariate analysis stromal AIP expression was an independent prognosticator of progression free survival, together with pT stage, histological grade and history of diabetes.

DISCUSSION

AIP Is a conserved cochaperone protein binding to many proteins. AIP has been proposed as a potential tumor suppressor gene. To date, no study has analyzed the immunohistochemical expression of AIP in pancreatic carcinoma. Our results indicate that both epithelial and stromal cytoplasmic expression of AIP is associated to bad prognosis, while nuclear translocation seems to improve prognosis.

CONCLUSION

Although we must deepen into the complex signaling pathways underlying this potential association, our results open a way to inhibiting AHR as a potential target against pancreatic carcinoma.

Preoperative management of obese patients undergoing bariatric surgery: Role of endoscopy and Helicobacter eradication

BACKGROUND

Obesity is a pandemic disease associated to severe health problems. Management is usually multimodal, but many patients eventually need surgery to reduce weight. Many guidelines recommend endoscopy prior to surgery. This study reviews a series of patients undergoing sleeve gastrectomy to see whether endoscopy performance and histopathological findings influence surgery outcome.

MATERIAL AND METHODS

Retrospective series of patients undergoing sleeve gastrectomy as bariatric procedure at a single institution. We have reviewed the demographic data, the associated pathologies, endoscopic findings prior to surgery, histopathological findings in the surgical resection specimen and postoperative complication rate.

RESULTS

259 patients fulfilled criteria for the study. Over 70% were women and the mean age was 46.9 (SD 9.8). Preoperative endoscopy was performed in 28.9% of the patients and biopsy only in 19.3%. Helicobacter pylori was detected in 28% of the patients undergoing endoscopy (either in the biopsy or the urease test) and eradicated before surgery in all the patients. Helicobacter pylori was present in 9.7% of the surgical resection specimens and its presence was significantly associated with the development of postoperative complications, mostly staple line leaks (p = 0.01).

CONCLUSION

Our study confirms that Helicobacter infection is significantly associated with postoperative complications after sleeve gastrectomy. It is therefore important to detect its presence and eradicate it before surgery.

SOD3 induces a HIF-2α-dependent program in endothelial cells that provides a selective signal for tumor infiltration by T cells

Background

Tumor-infiltrating lymphocytes (TILs), mainly CD8⁺ cytotoxic T lymphocytes (CTL), are linked to immune-mediated control of human cancers and response to immunotherapy. Tumors have nonetheless developed specific mechanisms that selectively restrict T cell entry into the tumor microenvironment. The extracellular superoxide dismutase (SOD3) is an anti-oxidant enzyme usually downregulated in tumors. We hypothesize that upregulation of SOD3 in the tumor microenvironment might be a mechanism to boost T cell infiltration by normalizing the tumor-associated endothelium.

Results

Here we show that SOD3 overexpression in endothelial cells increased in vitro transmigration of naïve and activated CD4⁺ and CD8⁺ T cells, but not of myeloid cells. Perivascular expression of SOD3 also specifically increased CD4⁺ and CD8⁺ effector T cell infiltration into tumors and improved the effectiveness of adoptively transferred tumor-specific CD8⁺ T cells. SOD3-induced enhanced transmigration in vitro and tumor infiltration in vivo were not associated to upregulation of T cell chemokines such as CXCL9 or CXCL10, nor to changes in the levels of endothelial adhesion receptors such as intercellular adhesion molecule-1 (ICAM-1) or vascular cell adhesion molecule-1 (VCAM-1). Instead, SOD3 enhanced T cell infiltration via HIF-2α-dependent induction of specific WNT ligands in endothelial cells; this led to WNT signaling pathway activation in the endothelium, FOXM1 stabilization, and transcriptional induction of laminin-α4 (LAMA4), an endothelial basement membrane component permissive for T cell infiltration. In patients with stage II colorectal cancer, SOD3 was associated with increased CD8⁺ TIL density and disease-free survival. SOD3 expression was also linked to a T cell–inflamed gene signature using the COAD cohort from The Cancer Genome Atlas program.

Conclusion

Our findings suggest that SOD3-induced upregulation of LAMA4 in endothelial cells boosts selective tumor infiltration by T lymphocytes, thus transforming immunologically “cold” into “hot” tumors. High SOD3 levels are associated with human colon cancer infiltration by CD8⁺ T cells, with potential consequences for the clinical outcome of these patients. Our results also uncover a cell type–specific, distinct activity of the WNT pathway for the regulation of T cell infiltration into tumors.

PAUF/ZG16B promotes colorectal cancer progression through alterations of the mitotic functions and the Wnt/β-catenin pathway

Pancreatic adenocarcinoma upregulated factor (PAUF), also known as ZG16B, was previously found in the secretome of metastatic colorectal cancer cells. Here, we demonstrated the presence of PAUF at the intracellular level and its multiple effects on cancer progression. An initial decline of PAUF expression was observed at early stages of colorectal cancer followed by an increase at the metastatic site. PAUF was located at different cellular compartments: membrane-associated vesicles, endosomes, microtubule-associated vesicles, cell growth cones and the cell nucleus. PAUF loss in two colorectal cancer cell lines caused severe alterations in the cell phenotype and cell cycle, including tetraploidy, extensive genomic alterations, micronuclei and increased apoptosis. An exhaustive analysis of the PAUF interactome using different proteomic approaches revealed the presence of multiple components of the cell cycle, mitotic checkpoint, Wnt pathway and intracellular transport. Among the interacting proteins we found ZW10, a moonlighting protein with a dual function in membrane trafficking and mitosis. In addition, PAUF silencing was associated to APC loss and increased β-catenin nuclear expression. Altogether, our results suggest that PAUF depletion increases aneuploidy, promotes apoptosis and activates the Wnt/β-catenin pathway in colorectal cancer cells facilitating cancer progression. In summary, PAUF behaves as a multifunctional protein, with different roles in cancer progression according to the extra- or intracellular expression, suggesting a therapeutic value for colorectal cancer.

TRIM72 Immunohistochemical Expression Can Predict Relapse in Colorectal Carcinoma

Large bowel adenocarcinoma is one of the most frequent human neoplasms and despite recent insights into the pathophysiology and molecular basis of this disease, mortality remains high in advanced and metastatic cases. Most guidelines recommend adjuvant chemotherapy for tumours involving lymph nodes, but not for patients with localized stage I or II disease. However, it is well known that approximately 20% of stage II colorectal carcinoma patients eventually recur, mainly with distant or peritoneal involvement and show bad prognosis. It would be important to predict which patients are at increased risk of recurrence to guide potential adjuvant therapy use in this controversial setting. In this sense, only microsatellite stability has been proposed as a predictive tool in some guidelines. The tripartite motif family protein 72 (TRIM72) is a ubiquitin ligase, involved in the cell membrane repair machinery and known to be associated to insulin resistance. Its potential role in colon cancer has recently been proposed. The aim of this study is to determine the potential predictive value of TRIM72 immunohistochemical expression in stage II colon carcinoma. We have retrospectively reviewed a series of 95 patients with stage II colon microsatellite stable carcinomas operated with a curative intent at a single large tertiary hospital in Madrid (Spain) between 2006 and 2012. None of the patients received adjuvant chemotherapy. We reviewed the histopathological slides and constructed a tissue microarray (TMA) of three representative areas to perform immunohistochemical staining for TRIM72. In our series 30 patients (31.7%) recurred after a median follow-up of 17.5 months. Lack of immunohistochemical expression of TRIM72 in the tumor was significantly and independently associated to recurrence. A recent report by Chen et al. has shown that TRIM72 can be measured in plasma for colon carcinoma detection as an alternative to CEA or CA19.9, with lower levels in patients with carcinoma. Our report is the first one to show that lower immunohistochemical expression of TRIM72 predicts recurrence in colon stage II carcinoma. We feel this predictive influence can be related to its crucial role as a central regulator in many signaling pathways (PI3K-AKT, ERK). As an ubiquitin ligase, the lack of TRIM72 could increase the levels of several potential oncogenic molecules and therefore lead to a more aggressive phenotype. It remains to be shown whether chemotherapy could change the clinical behaviour of this bad prognosis group. We propose TRIM72 immunohistochemical analysis as a potential tool to predict recurrence risk in stage II colon carcinoma patients. Our results should be confirmed in larger series, but could open the way to management strategies refinement in this early stage group of patients.

Histopathological changes associated to an absorbable fibrin patch (Tachosil®) covering in an experimental model of high-risk colonic anastomoses

BACKGROUND

TachoSil® is a fibrin sponge that contains fibrinogen and thrombin and is a useful adjuvant to enhance control of air leaks in thoracic surgery and to control bleeding in vascular and general surgery. Its use in intestinal surgery to prevent suture dehiscence is currently under investigation.

MATERIAL AND METHODS

We report the results of a prospective randomized experimental study on 33 large white pigs in which a high-risk suture was created by induction of ischemia. We randomly employed TachoSil® to cover the anastomosis in half of the animals compared to a control group of uncovered anastomosis. After euthanasia, postmortem analysis was performed describing the findings related to anastomotic leakage, peritonitis and grade of adhesions. The entire anastomosis was resected in bloc and sent for histopathological analysis. A single blinded-pathologist evaluated the histopathological features of the specimens.

RESULTS

We found statistically significant differences favouring the patch in decreasing leakage in the covered group. The healing process did not show significant differences between groups, although a higher rate of microscopic abscess was observed in the covered group.

CONCLUSION

The use of fibrin sealants covering high-risk intestinal sutures has a positive effect in avoiding macroscopic anastomotic leakage. The patch did not have any influence in the anastomotic healing process, however, as a result of the effect in containing the inflammatory response, it may increase the rate of abscess.

Histopathological factors predicting response to neoadjuvant therapy in gastric carcinoma

BACKGROUND

Neoadjuvant therapy (NAT) is a useful therapeutic option. However, some patients respond poorly to it and can even show tumor progression. It is important to define factors that can predict response to NAT.

MATERIALS AND METHODS

This is a retrospective cohort study to define histopathological factors predicting response to NAT in gastric tubular carcinoma. This study has enrolled 80 patients receiving chemotherapy for locally advanced gastric carcinoma.

RESULTS

44.5% of the patients were men; mean age was 64.49 years. Only 5.7% of the patients showed a complete response to therapy, 10% had grade 1, 21.4% grade 2, and 62.9% grade 3 regression. On follow-up, 43.8% of the patients showed recurrence of disease (57.1% distant metastasis) and 33.8% eventually died of it. We found a statistically significant association between response and prognosis. We found a statistically significant association between regression and perineural, vascular, and lymph vessel invasion. Logistic regression model showed that only lymph vessel invasion had independent influence. Lymph vessel invasion not only indicated lack of response to therapy, but also higher incidence of lymph node involvement in the gastrectomy specimen.

DISCUSSION

Our study indicates that the presence of vascular or perineural invasion in the endoscopic biopsies and high histopathological grade predict poor response to therapy. This seems peculiar, for undifferentiated tumors are supposed to have better response to therapy.

CONCLUSION

Our study indicates that undifferentiated tumors respond worse to therapy. Furthermore, studies are necessary to define lack of response, to help avoid neoadjuvant therapy in unfavorable cases.

CPEB4 immunohistochemical expression is associated to prognosis in stage IV colorectal carcinoma

The cytoplasmic polyadenylation element binding protein 4 (CPEB4) is a RNA binding protein and translational regulator. It has been associated with tumor growth, vascularization and invasion and with tumor progression in breast, pancreas and lung carcinomas. To the best of our knowledge only one previous report has analyzed the prognostic value of CPEB4 in an experimental model of colorectal carcinoma. We have reviewed the files of patients with stage IV colorectal carcinoma metastatic to the liver. All the patients had received chemotherapy followed by hepatic metastasis resection and subsequent resection of the colon (liver-first approach). We have gathered demographic, analytical and morphological data of the primary tumors. We have performed immunohistochemical analysis of CPEB4 expression in these tumors and analyzed the potential prognostic value of this protein. 50 patients fulfilled inclusion criteria for the present study. All of them received preoperative chemotherapy based on platinum and also postoperative chemotherapy, with or without targeted drugs (18% received anti-epidermal growth factor receptor (EGFR) drugs and 24% anti-vascular endothelial growth factor receptor (VEGFR) drugs. 66% of the primaries were of sigmoid-rectal origin. CPEB4 expression was mainly cytoplasmic and it was scored as intense in 46% of the patients. Survival analysis revealed a significant association between progression free survival (PFS) and overall survival (OS) and CPEB4 immunohistochemical expression, which was independent in the multivariate analysis. CPEB4 behaves as a significant predictor of prognosis in stage IV colorectal carcinoma. The existence of CPEB4 specific inhibitors can open a new way for targeted therapy. Larger prospective studies are needed to confirm our promising results.

Decreased PLK1 expression denotes therapy resistance and unfavourable disease-free survival in rectal cancer patients receiving neoadjuvant chemoradiotherapy

AIM

Polo-like kinase 1 (Plk1) plays a key role in mitotic cell division and DNA damage repair. It has been observed that either up-regulated or down-regulated Plk1 could induce mitotic defects that results in aneuploidy and tumorigenesis, probably depending on the context. Few previous reports have associated Plk1 expression with prognosis and response to radiotherapy in rectal carcinomas. The aim of this study is to investigate the prognostic impact of Plk1 expression and its role in predicting response to neoadjuvant cheomoradiotherapy in rectal cancer.

METHODS AND RESULTS

Immunohistochemical analysis of Plk1 expression was performed in the pre-treatment tumour specimens from 75 rectal cancer patients. We analysed the assocation between Plk1 expression and clinicopathological parameters, pathologic response and outcome. Opposed to previous reports on this issue, low expression of Plk1 was significantly associated with a high grade of differentiation (P=0.0007) and higher rate of distant metastasis (P=0.014). More importantly, decreased levels of Plk1 were associated with absence of response after neoadjuvant therapy (P=0.049). Moreover, low Plk1 expression emerged as an unfavourable prognostic factor for disease-free survival in the non-responder group of patients (P=0.037).

CONCLUSIONS

Decreased Plk1 expression was associated with poor pathologic response and worse disease-free survival in rectal cancer patients receiving neoadjuvant chemoradiotherapy, suggesting Plk1 as a clinically relevant marker to predict chemoradiotherapy response and outcome.

Focal adhesion kinase: predictor of tumour response and risk factor for recurrence after neoadjuvant chemoradiation in rectal cancer

Rectal cancer represents about 30% of colorectal cancers, being around 50% locally advanced at presentation. Chemoradiation (CRT) followed by total mesorectal excision is the standard of care for these locally advanced stages. However, it is not free of adverse effects and toxicity and the complete pathologic response rate is between 10% and 30%. This makes it extremely important to define factors that can predict response to this therapy. Focal adhesion kinase (FAK) expression has been correlated with worse prognosis in several tumours and its possible involvement in cancer radio‐ and chemosensitivity has been suggested; however, its role in rectal cancer has not been analysed yet. To analyse the association of FAK expression with tumour response to CRT in locally advanced rectal cancer. This study includes 73 patients with locally advanced rectal cancer receiving standard neoadjuvant CRT followed by total mesorectal excision. Focal adhesion kinase protein levels were immunohistochemically analysed in the pre‐treatment biopsies of these patients and correlated with tumour response to CRT and patients survival. Low FAK expression was significantly correlated with local and distant recurrence (P = 0.013). Low FAK expression was found to be a predictive marker of tumour response to neoadjuvant therapy (P = 0.007) and patients whose tumours did not express FAK showed a strong association with lower disease‐free survival (P = 0.01). Focal adhesion kinase expression predicts neoadjuvant CRT response in rectal cancer patients and it is a clinically relevant risk factor for local and distant recurrence.

PLK-1 Expression is Associated with Histopathological Response to Neoadjuvant Therapy of Hepatic Metastasis of Colorectal Carcinoma

Polo-like kinase 1 (PLK1) is a serine/threonine-protein kinase expressed during mitosis and overexpressed in multiple human cancers, including leukemia and also many solid tumors. PLK1 knockdown has been shown to block proliferation of leukemic cell lines and the clonogenic potential of tumor cells grown from patients with cancer. PLK1 inhibition is a promising strategy for the treatment of some tumors. We aim to analyze expression of PLK1 in metastatic colorectal carcinoma. Retrospective analysis of colorectal carcinomas with hepatic metastasis during follow-up receiving neoadjuvant chemotherapy (NAC), based on oxaliplatin. Immunohistochemistry for PLK-1 in paraffin-embedded tissue from the primary and also from the metastasis. 50 patients. 32% showed good histopathological response. 43% of the primaries were positive for PLK1, as opposed to 23.5% of the metastasis. Expression of PLK1 was significantly reduced in metastasis compared with the primaries (p = 0.05), what could be due to therapy or to a phenotypic change of the metastatic nodule. Analysis of the prognostic influence of PLK1 expression showed significant association between PLK1 expression in metastasis and lower overall survival (p = 0.000). We have also found a significant association between PLK1 expression and histopathological response (p = 0.02). All the tumors with high expression of PLK1 showed minor response (11/11). This study shows the association between survival and poor histopathological response to therapy and high expression of PLK1 in metastasis. Our results could open a new therapeutic approach through the inhibition of PLK1.

Meniscal degeneration in human knee osteoarthritis: in situ hybridization and immunohistochemistry study

OBJECTIVE

Meniscus injury is one of the causes of secondary osteoarthritis (OA). However, the role of meniscus is still unclear. Human meniscal distribution of cells and cartilage oligomeric matrix protein (COMP) and their changes in advanced OA were analyzed.

PATIENTS AND METHODS

Thirty-one medial menisci from patients with knee OA that underwent a total knee arthroplasty were studied. Normal meniscal tissue was obtained from partial arthroscopic meniscectomy. Meniscal samples were processed for histology, immunohistochemistry and in situ hybridization, for cell assessment including density, active divisions, apoptosis, COMP distribution and proteoglycan content.

RESULTS

Osteoarthritic menisci demonstrated areas of cell depletion and significant decrease in COMP immunostaining. Actively dividing cells were only found in the meniscectomy group, but not in the osteoarthritic group. Proteoglycan staining was less prominent in menisci from the osteoarthritis group.

CONCLUSIONS

Our results show a decreased cell population, with low COMP and altered matrix organization in osteoarthritis menisci that suggest an altered meniscal scaffold and potential impairment of meniscal function. These meniscal changes may be associated with the development of knee osteoarthritis.

Prognostic significance of tumor regression in lymph nodes after neoadjuvant therapy for rectal carcinoma

Neoadjuvant therapy (NAT) is mainly indicated for locally advanced rectal carcinoma. Many reports have shown that regression of the primary tumor is a prognostic factor. However, few reports to date have analyzed the potential prognostic significance of lymph node regression in rectal carcinoma. The aim of the present study is to describe the pattern of tumor regression in lymph nodes after NAT for rectal carcinoma and its potential prognostic significance. We have retrospectively reviewed 106 cases of rectal carcinoma treated at a single institution. We have retrieved data from the patients and reviewed the histopathological slides to evaluate tumor regression both of the primary tumor and of LN metastases. Prognosis has been defined both in terms of disease-free survival (DFS) and disease-specific survival (DSS). Of the patients, 16% showed complete response of the primary tumor, while 24% showed poor response, according to the CAP regression grading system. Absence of lymph node involvement after therapy was found in 80% of the patients (ypN0 cases), while 20% were ypN+. We reviewed 639 LN; 85 were involved by tumor, and 170 showed histological signs of tumor regression. The main pattern of tumor regression in lymph nodes was fibrosis (66.3%), followed by hystiocytosis (29.1%) and mucin pools (4.6%). We found histological signs of regression in 57% of ypN0 cases and 76% of ypN+ cases. We found a significant association between regression grade of the primary tumor and of lymph node metastases. For ypN0 patients with persistence of the primary tumor after NAT, the median DFS was significantly shorter in patients showing tumor regression in the LN. In a Cox multivariate survival model for DFS, this prognostic influence was independent of the regression grade of the primary tumor and also of the ypTNM stage. We found no significant association between any factor and DSS. The pattern of tumor regression in lymph nodes was not significantly associated with prognosis. Tumor regression in lymph nodes is an important prognostic factor in rectal carcinoma after NAT and should be specifically looked for and included in pathology reports.

Evaluation of a minimally aggressive method of patellofemoral osteoarthritis treatment at 10 years minimum follow-up

BACKGROUND

Knee osteoarthritis mainly affecting the lateral facet of the patella, especially in young patients, is a definite challenge to the surgeon. Our purpose was to investigate the long-term outcome of a simple operation such as the partial lateral facetectomy on middle-aged to elderly patients with predominant lateral patellofemoral osteoarthritis.

METHODS

A retrospective, long-term study of 39 knees (28 females, mean aged at surgery 61yearsold) with a minimum follow-up of 10years was performed. Evaluations included preoperative and postoperative questionnaires, physical examinations, and radiographs.

RESULTS

The main outcomes included the initial anterior pain relief, with higher scores using the Knee Society Score (that improved in 84% of the knees), and the eventual failure of the technique, including percentage of patients that required secondary total knee replacement (30% of the knees).

CONCLUSION

Partial lateral facetectomy aiming to decrease the high pressure in the lateral facet of the patella confirmed frequent pain relief. This surgical procedure being minimally invasive, relatively simple, and effective in selected patients, is a valid early alternative to more complex operations and does not preclude further reconstructive surgery in case of disease progression.

Implementation of a joint protocol for the management of thyroid nodules with a cytological diagnosis of follicular lesion of undetermined significance: experience in one hospital

BACKGROUND

Follicular lesion of undetermined significance (FLUS) was introduced for fine needle aspiration (FNA) cytology in which there is insufficient evidence to classify the lesion as follicular neoplasm/suspicious of follicular neoplasm or suspicious for malignancy. The recommended management was repeat FNA and correlation with clinical and radiological data. In 2009 we started a joint clinicopathological protocol to improve management of FLUS, recommending follow-up with repeat FNA at 6months. The aim of this study was to report on the audit of results of this protocol.

METHODS

We reviewed the medical records of the patients with FLUS at a single hospital. Between 2007 and 2010 we found 135 cases with this diagnosis (3.6%). We only had long enough follow-up information for the 95 patients that were included in the present study.

RESULTS

FLUS was diagnosed in 74 FNAs before protocol implementation (3.2%) and 61 FNAs after (4.2%), with follow-up of 46 and 49 patients, respectively. Before 2009, 38/46 (82.6%) patients had surgical excisions, compared with 32/49 (65.3%): a significant reduction of 17% in the number requiring surgery (P=0.05). We have also shown a reduction in the median time to surgery (11.9 versus 2.9 months). Despite the joint protocol, the FNA was only repeated in two patients. The histological diagnoses were similar in the two periods of time: 31.6% and 31.3% follicular adenomas; 13.1% and 3.1% (P=0.2) papillary carcinoma (follicular variant).

CONCLUSIONS

Implementation of a joint protocol reduced the number of surgical operations in patients with FLUS but in most cases FNA was not repeated as recommended. Excision was justified in one-third of operated patients. Less than 15% of lesions were malignant, which is in accordance with previous reports in the literature.

An experimental study of COMP (cartilage oligomeric matrix protein) in the rabbit menisci

INTRODUCTION

Secondary knee osteoarthritis (OA) is currently associated with meniscal injuries, but the pathogenesis is unclear. We analyzed the distribution of cells and cartilage oligomeric matrix protein (COMP) and its changes in the early stages of degeneration in meniscus.

METHOD

Ten New Zealand rabbits underwent anterior cruciate ligament (ACL)-transection of the right knee-joint. Left knee-joints were used as controls. The animals were killed at 4 and 12 weeks. Gross injuries in meniscus and articular cartilage were scored. Meniscal tissues were immunostained with a specific antibody against COMP, with Ki-67, using TUNEL-assay and alcian blue stain. The number of cells was counted.

RESULTS

At 4 weeks post-ACL-transection, 2/5 of the operated knees showed articular damages and medial menisci tears. Menisci showed a weak increase of cells, higher in cells under division and an increase of apoptosis, COMP and proteoglycans. At 12 weeks, 5/5 of the medial menisci and 2/5 of lateral menisci presented tears, and osteoarthritic changes were seen in the cartilage of all the operated knees. Meniscal cells reverted to normal number, while active cell division decreased below normal, apoptotic events were still high, COMP remained elevated, and glycosaminoglycans were even more elevated.

CONCLUSION

Extracellular matrix changes and altered cell distribution occur early in the degenerative meniscus. There is a close relationship between changes in the articular cartilage and the menisci at the onset of secondary OA.

[Early histopathological aspects of benign prostatic hyperplasia: myxoid-inflammatory nodules]

OBJECTIVES

Infiltration of benign prostatic hyperplasia (BPH), nodular prostatic hyperplasia (NPH) or prostatic adenoma by mononuclear cells, predominantly lymphocytes, is a common finding in surgical specimens. The biological significance of this infiltration, very similar to chronic inflammation, is unknown, but it is suspected as being related to the pathogenesis and progression of the BPH. The identity and number of the infiltrating cells is not well known. The objectives of the present study were: 1) to describe in more detail the histologic pattern of early lesions BPH, that is myxoid nodules. 2) to count and locate these myxoid nodules and to analyse the possible influence of age 3) and describe the patterns of mononuclear cell infiltration in BPH.

MATERIALS AND METHODS

One hundred and seventy-three specimens of BPH tissue were reviewed. These samples were processed routinely for histological examination and immunohistochemical examination was performed in selected cases in order to further define the cellular composition of the described lesions. The immunohistochemical stains were performed automatically. Vimentin, specific smooth muscle actin an desmin were use to show the stromal cells and CD3, CD20 and CD68 monoclonal antibodies were used to quantify the populations of T-lymphocytes, B-lymphocytes and macrophages, respectively. The number of myxoid nodules identified in each patient was counted and the maximum and minimum diameter measured. These data have been compared in two groups of patients, those younger than 57 years and those over 80. Statistical analysis has been performed with SPSS 13.0. Student s t test was used for bivariate analysis and Pearson s r for correlation.

RESULTS

Interstitial infiltration involving T and B lymphocytes with less macrophages was a constant finding of the early nodules of BPH. The bivariate analysis with Student s t has shown a statistically significant difference between the mean number of myxoid nodules (p<or=0.02), significantly lower in the younger patients. Although we have found differences between the mean diameters of the smallest and the largest nodules in both groups, these differences did not reach statistical significance. We have not shown any significant correlation between the number of nodules and the patient age (p<or=0.11) in the Pearson s correlation.

CONCLUSION

Inflammatory cells and myxoid nodules are a constant finding in BPH surgical samples. The mean number of myxoid nodules is significantly lower in younger patients. Interstitial distribution is the most common pattern of mononuclear cell infiltration. B and T-cell lymphocytes are the most frequently found inflammatory cells in early myxoid nodules.

Cutaneous endometriosis: review of 15 cases diagnosed at a single institution

INTRODUCTION

Endometriosis is a disease characterized by the presence of endometrial glands and/or stroma outside the uterine cavity. The main location is the ovary, but it has been described in many other extragenital locations, mainly the intestinal wall and the epiplon, but also the lung and the skin.

MATERIALS AND METHODS

In this report we review the cases of cutaneous endometriosis diagnosed at Fundación Jiménez Díaz in Madrid in the last decade.

RESULTS

In this time period we have seen 376 specimens with endometriosis, 330 from ovarian origin, 11 cases involving the appendix, 3 affecting the uterine cervix, 3 involving the epiplon, 1 in an ileal lymph node, 5 in the small intestine, 6 in the large intestine, 2 affecting the lung (with recurring pneumothorax) and 15 involving the skin.

CONCLUSION

We comment on the features of the patients with cutaneous endometriosis and their gynaecological history.

Utility of a simplified molecular classification of tumors for predicting survival of patients with invasive ductal breast carcinoma

BACKGROUND

In a recent report it was shown that molecular subgroups of early (pT1) breast tumors belonging exclusively to the most common histological variant, ductal-infiltrating carcinoma, showed significantly different clinical and biological features.

OBJECTIVE

To test in a series of patients with ductal-infiltrating carcinoma encompassing all stages of the disease if the above-mentioned biological differences already detected at the earliest stage are ultimately reflected in survival differences.

PATIENTS AND METHODS

All patients with ductal infiltrating carcinoma operated upon at Hospital de Móstoles, Madrid, Spain, between 1997 and 2002 were included into the study, to allow for at least five years of follow-up for survivors. Of 242 studied patients, according to the International Federation of Gynecology and Obstetrics (FIGO) classification, 37.6% were in stage I, 47.2% in stage II, 11.0% in stage III, and 4.2% in stage IV. According to the simplified molecular classification of Carey et al., 116 tumors (47.9%) expressed estrogen receptors, and did not express c-erb-B2 (Luminal A), 67 (27.7%) coexpressed hormone receptors (either estrogen receptors, progesterone receptors or both) and c-erb-B2 (Luminal B), 33 (13.3%) expressed c-erb-B2 in the absence of hormone receptors (HER-2), and 26 (10.7%) neither expressed hormone receptors, nor c-erb-B2 (triple-negative, basal).

RESULTS

In a univariate model, both disease-free survival and overall survival of the patients were significantly associated with stage (p=0.0003; p<0.0001), histological grade (p<0.0001; p<0.0001), lymphatic vascular space invasion (p=0005; p=0.0044), menopausal status (p=0.04; p=0.034) and molecular subgrouping (p=0.037: p=0.01). In a multivariate model, only stage (p=0.013), grade (p<0.0001), and menopausal status (p=0.007) retained their prognostic power for predicting disease-free survival, and just stage (p<0.0001) and grade (p<0.0001) for predicting overall survival. The molecular classification of the tumors almost reached statistical significance for predicting overall survival (p=0.06).

Atypical cells in the urinary sediment: a protocol for cytological analysis of the urinary sediment

INTRODUCTION

The Department of Clinical Chemistry of the General Hospital of Móstoles (Madrid, Spain) has for many years diagnosed the presence of atypical cells in the urinary sediment (ACUS), but this finding only led to a comment in the final report of the urinalysis, informing the clinician of this fact in case he/she decided to perform further studies in these patients.

METHODS

Since 2004, the Clinical Chemistry Department has implemented a new protocol together with the Department of Surgical Pathology of the Hospital, according to which all the urinary sediment samples with ACUS are sent for cytological analysis. In this report, we comment on the results corresponding to 99 samples.

RESULTS

With this new strategy, we can directly diagnose if the ACUS correspond to a carcinoma or to another process, and this has allowed us to reduce time until diagnosis in our patients and also to avoid unnecessary studies in negative cases. We comment on our results with this new management strategy.

[Sclerokeratitis and invasive conjunctival squamous cell carcinoma]

PURPOSE/METHODS

To describe one case of invasive squamous cell carcinoma of the conjunctiva in a 74-year-old woman, who two years previously had presented with a lesion which appeared to be an anterior nodular scleritis.

RESULTS/CONCLUSIONS

An anterior nodular scleritis, which did not respond to therapy, preceded the development of a squamous cell carcinoma of the conjunctiva adjacent to it. In our patient, the conjunctival squamous cell carcinoma could have masqueraded as a scleritis, delaying the correct diagnosis and allowing orbital spread of the tumor. A diagnosis of neoplasia must be considered when a scleritis shows an atypical appearance or does not respond to the usual therapy.

Gluten intolerance: sex and age-related features

OBJECTIVE

Gluten intolerance is an immune-mediated enteropathy associated with gluten-containing foods in genetically susceptible patients. The typical form mainly affecting children shows failure to thrive and/or gastrointestinal symptoms. The adult form is less typical, presenting vague gastrointestinal symptoms, iron deficiency (with or without anemia) or nonspecific serum chemistry abnormalities. The present study aims to analyze clinical and biochemical differences of celiac disease (CD) according to sex and age.

PATIENTS AND METHODS

The present study reviewed clinical and biochemical features of patients with suspected CD admitted to the Hospital General of Móstoles (Madrid, Spain) between July 2001 and June 2005. Two hundred fifty-two patients were analyzed, in whom intestinal biopsy was performed due to clinical and/or biochemical abnormalities suggestive of CD. One hundred seventy-eight asymptomatic relatives of the affected patients were also included. Overall, 125 patients showed diagnostic features of CD in the intestinal biopsy.

RESULTS

The results confirmed higher prevalence of typical forms of CD in children (67% in children compared with only 14.3% in adults). CD seemed to be more frequent in adult women than in men (ratio of women to men 4:1), but it is worth noting that men diagnosed were most often referred with a typical clinical picture, so atypical forms of the disease in men may have been underdiagnosed.

CONCLUSIONS

CD shows atypical features in adults, and physicians must include this disorder in the differential diagnosis of adults with iron deficiency or slight hypertransaminasemia. Increased awareness of the disease and extensive availability of accurate sero-logical tests will lead to improved diagnosis of this disorder, both in children and adults.

Uremia associated with erythrophagocytosis by small intestine epithelial cells: a case report

BACKGROUND

Anemia is a frequent finding in patients with uremia due to chronic renal failure. Two factors contribute to the decrease in the red blood cell count and worsen the patient's general status: depression of erythropoiesis and shortening of the red blood cell lifespan.

CASE

A novel response mechanism to erythrocyte loss took place in a uremic patient with gastrointestinal hemorrhage. In an autopsy case of an 80-year-old woman dying of uremia, analysis of an intestinal fluid smear revealed small intestine epithelial cells engulfing complete erythrocytes.

CONCLUSION

This cytologic finding could account for a potential response mechanism to counteract the massive erythrocyte loss that occurs in hemorrhagic anemia with a uremic background.

Two consecutive outbreaks of Acinetobacter baumanii 1-a in a burn Intensive Care Unit for adults

Acinetobacter baumanii is generally a highly antibiotic resistant micro-organism that can be easily transmitted between inpatients of ICUs. We report two consecutive outbreaks of A. baumanii in a burn ICU.

MATERIAL AND METHODS

All patients with ICU-stay greater than 2 days were subject to a strict epidemiological surveillance after admission, recording age, sex, TSBA, etc. and follow-up data such as antibiotherapy, instrumentation, infections, etc. We also monitored the microbial flora evolution and their resistance to antibiotic by weekly cultures of pharynx, rectum, skin (healthy and burned), etc. Because of an "epidemic" microorganism, infection control procedures, were increased. We studied the colonization by other prevalent microorganisms: MR-S. aureus and Pseudomonas aeruginosa.

RESULTS

Seventy-two burn patients were followed in 1 year. Only 4.1% were infected at some site by A. baumanii, but 1/3 of patients were colonized by this microorganism, distributed in two outbreaks, one in the first trimester, after admission in the Unit of two non-burned and colonized patients (from another ICU). The second epidemic began in July and probably was due to transitory colonization of skin or fomites by health personnel working in both ICUs. All the isolates (from both ICUs) of A. baumanii were identical by PFGE. The length of hospital stay was the main risk factor for colonization. P. aeruginosa and MR-S. aureus showed a tendency to be endemo-epidemic at all times.

CONCLUSION

Our cross colonization control measures showed a limited efficacy our burn patients. Therefore, we must impede the introduction to burn ICUs of epidemic microorganisms by colonized patients or heath personnel by restriction of admission of A. baumanii colonized patients from other ICUs (if the treatment can be administered in this ICU) and by strict disinfection/antiseptic procedures.

Gastric Actinomycosis: a Rare Complication after Gastric Bypass for Morbid Obesity

A 41-year-old woman in November 2002 underwent a gastric bypass by the Capella technique for morbid obesity. Almost 1 year after the surgery, she developed severe vomiting. Radiological studies confirmed a severe stenosis of the gastrojejunal anastomosis. Two pneumatic dilatations of the stenosis failed. In February 2004, she underwent resection of the stenotic anastomosis. Histology showed an intact mucosa and beneath it an abscess filled with numerous filamentous microorganisms, with typical features of Actinomyces. With the diagnosis of gastric actinomycosis, she received a postoperative course of antibiotherapy with imipenem and was discharged after an uneventful recovery. Gastric actinomycosis is a rare infection, of which only 19 additional cases have been reported in the literature. To our knowledge, this is the first case to affect a patient following batriatric surgery. The reported cases of this entity are reviewed, and the diagnostic criteria that could avoid surgery in these cases are discussed.

The influence of laboratory adaptation on test strains, such as Pseudomonas aeruginosa, in the evaluation of the antimicrobial efficacy of ortho-phthalaldehyde

The microbiocidal efficacy of 0.55% ortho-pthalaldehyde (OPA) was evaluated in a rough carrier test, using more than 200 strains of bacteria and yeasts from patients and reference ATCC strains. This test was then compared with the European carrier test (prEN14561) using Pseudomonas aeruginosa. We also sought to determine whether recently isolated P. aeruginosa had the same susceptibility to OPA, after laboratory adaptation. It was shown that P. aeruginosa was less susceptible to OPA (being reduced by a factor of 10(3.8)) than the other strains (reduced by a factor of 10(4)). The surface test used, produced a lesser reduction of P. aeruginosa than the European test. For recently isolated strains (N = 66), the rough model demonstrated that the number of survivors increased both quantitatively and qualitatively from day one to day seven. It was concluded that disinfectant efficacy should be confirmed with recently isolated organisms.

Prognostic significance of microvascular counts in rectal carcinoma

Numerous studies of many tumor types have demonstrated that microvessel quantitation as a measure of angiogenesis is a powerful prognostic tool. Vascular enumeration has been claimed to be an independent prognosticator for several human tumors, including breast carcinoma, melanoma or bladder carcinoma; however, the studies of colorectal cancer have rendered variable results. To test the prognostic influence of this factor in our patients, we selected 39 patients with rectal carcinoma Dukes' stages A to C treated only with curative surgery, with no further adjuvant therapy. The minimal follow-up time was 5 years (60 months). After immunostaining with CD34, we performed a manual count of the vessels following Gasparini's criteria. In our series, vascular enumeration has been a prognosticator for OS (overall survival) but not for RFS (relapse-free-survival) at all Dukes' stages in the univariate analysis. This prognostic influence was lost in the multivariate analysis, in which only stage as well as vascular and neural invasion behaved as significant independent prognosticators. The presence of hypervascularization did not show any significant association with histologic grade, tumor staging, and vascular or neural invasion.

Malignant spiradenoma: report of two cases and literature review

Spiradenoma is a benign skin adnexal neoplasm that usually appears as a solitary nodule in any area of the body. There have been only 33 reports on malignant transformation of a benign eccrine spiradenoma since the first description by Dabska in 1972. Most cases have originated on a long-standing cutaneous lesion. These tumors can behave in an aggressive fashion, and some have led to the patient's death. We report 2 new cases of this rare neoplasm affecting 2 men, 92 and 72 years of age, comment on the clinical and pathologic features of our cases, and review the literature concerning this lesion.

Prognostic influence of tumor-associated eosinophilic infiltrate in colorectal carcinoma

BACKGROUND

In 1983, Pretlow et al. reported one classical study of the prognostic influence of eosinophil infiltration in human colon carcinoma. Since then, very few reports have analyzed this supposed prognostic influence in this type of tumor, although there have been several reports of other types of tumors with different results. Eosinophils seem to play a central role in the immunologic defense against tumors; their activity can be induced through immunotherapy with interleukin in cases that are unresponsive to conventional therapies.

METHODS

To analyze the prognostic influence of eosinophils in colorectal carcinoma, the authors selected 126 patients with this type of tumor treated only with curative surgery and followed for a minimal period of 5 years. They divided these patients into 4 categories according to the number of eosinophils per high-power field (400x): 0 (Grade 1), 1-9 (Grade 2), 10-50 (Grade 3), and more than 50 (Grade 4).

RESULTS

The results of this series confirm that high eosinophil counts are associated with a significantly better prognosis. In multivariate analysis, this factor was independent from staging, vascularization, p53 expression, and histologic grade.

CONCLUSIONS

Eosinophil count served as a significant independent favorable prognosticator in colorectal carcinoma patients.

p53 expression in two cases of spiradenocarcinomas

p53 protein is a nuclear 53-kDa phosphoprotein that acts as a suppressor protein. There are several studies on the expression of p53 in skin tumors, but few deal with adnexal malignant tumors because of their rarity. We performed immunohistochemistry for the detection of p53 and Ki-67 in two cases of malignant spiradenomas and six cases of spiradenomas retrieved from our files. In our cases, p53 was expressed only in the malignant areas of the lesions, whereas the benign areas of the spiradenocarcinomas and all the spiradenomas were negative (nuclear positivity <10%). These results seem to support the idea that p53 is implicated in the malignant transformation of adnexal tumors.

[The cost effectiveness of echography biopsy]

Ecopsy is a postmortem technique which, by means of echography-guided puncture and/or aspiration obtains material for histological analysis. This study compared cost and time employed in 100 ecopsies and 100 classic necropsies and confirmed that cost of materials in ecopsy is 65% lower than that in necropsy. Physicians, necropsy technicians, laboratory technicians and secretary team personnel spent 33%, 54%, 19% and 32% less time than in necropsy. The clinical report of ecopsy was finished within nine days even with the brain study included.

Laryngeal liposarcoma: report of a case

Laryngeal and hypopharyngeal liposarcomas are fairly rare tumors, with only 30 convincing cases reported to date. These tumors usually arise in the supraglottic area, and only two cases have been reported to affect the true vocal cord. They behave in an indolent fashion with multiple local recurrences and only rarely cause the patient's death. Our case highlights the natural history of this entity. A 62-year-old man presented because of air-way obstruction. A CT scan discovered a large 5 cm polypoid mass in the right aryepiglottic fold. The patient had already undergone three previous operations for the same reason in another clinic, with histopathological diagnoses of fibrovascular polyps. In the last recurrence, only a careful search for lipoblasts in the surgical specimen allowed us to identify this lesion as a low-grade well-differentiated liposarcoma. Complete resection was impossible in this case, despite total laryngectomy.

Evaluation of ultrasonography and clinical diagnostic scoring in suspected appendicitis

BACKGROUND

Several diagnostic aids have been developed to improve diagnosis in suspected appendicitis including ultrasonography and clinical diagnostic scoring. The aim of this study was to elaborate a new scoring system and to measure its accuracy in the preoperative diagnosis of appendicitis, comparing it with the available scoring systems.

METHODS

The clinical, radiological and ultrasonographic data of 192 patients with suspected appendicitis were collected prospectively.

RESULTS

Only six of the 12 variables analysed were shown to have prognostic significance. Using Bayesian methodology, a weight was given to each criterion and two overall scores were calculated (ultrasonographic and classical scores). A cut-off point was identified to separate patients who needed surgery and those for observation. The ultrasonographic score showed an 81 per cent sensitivity and a 96 per cent specificity, compared with 60 and 73 per cent respectively for the classical score.

CONCLUSION

Ultrasonography increases the diagnostic accuracy in patients with suspected acute appendicitis.

Pulmonary toxicity of cadmium in rats: a histologic and ultrasound study

Several studies have shown a carcinogenic effect of inhaled or injected cadmium in rats. This carcinogenity has not yet been confirmed in humans. We have performed a study with 48 Wistar male rats, to which we have administered either cadmium sulphide (0.2 mg/Kg/day) or the same doses of placebo for four or eight days. 24 hours after the last administration, the rats were euthanised and an autopsy was performed. The histologic changes in the lung of the cadmium-exposed group were diffuse areas of alveolar collapse due to narrowing of the bronchioles secondary to the alteration of the surrounding connective tissue, with compensating alveolar emphysema near these foci and also at the periphery of the lung. There was also an increased number of intra-alveolar macrophages. We also noticed small foci of dysplasia in the alveolar epithelium. Ultrastructural changes were inspecific but suggested a toxic effect of cadmium on the epithelium. These findings, absent in the control group, confirm that intrathoracic injection of cadmium is associated with an increased tendency to the development of pulmonary emphysema and with dysplastic changes in the alveolar epithelium (peribronchiolar alveolar dysplasia).