Christian Andreas Nebiker

Clinical impact of programmed cell death ligand 1 expression in colorectal cancer.

BACKGROUND Programmed cell death 1 (PD-1) receptor triggering by PD ligand 1 (PD-L1) inhibits T cell activation. PD-L1 expression was detected in different malignancies and associated with poor prognosis. Therapeutic antibodies inhibiting PD-1/PD-L1 interaction have been developed. MATERIALS AND METHODS A tissue microarray (n=1491) including healthy colon mucosa and clinically annotated colorectal cancer (CRC) specimens was stained with two PD-L1 specific antibody preparations. Surgically excised CRC specimens were enzymatically digested and analysed for cluster of differentiation 8 (CD8) and PD-1 expression. RESULTS Strong PD-L1 expression was observed in 37% of mismatch repair (MMR)-proficient and in 29% of MMR-deficient CRC. In MMR-proficient CRC strong PD-L1 expression correlated with infiltration by CD8(+) lymphocytes (P = 0.0001) which did not express PD-1. In univariate analysis, strong PD-L1 expression in MMR-proficient CRC was significantly associated with early T stage, absence of lymph node metastases, lower tumour grade, absence of vascular invasion and significantly improved survival in training (P = 0.0001) and validation (P = 0.03) sets. A similar trend (P = 0.052) was also detectable in multivariate analysis including age, sex, T stage, N stage, tumour grade, vascular invasion, invasive margin and MMR status. Interestingly, programmed death receptor ligand 1 (PDL-1) and interferon (IFN)-γ gene expression, as detected by quantitative reverse transcriptase polymerase chain reaction (RT-PCR) in fresh frozen CRC specimens (n = 42) were found to be significantly associated (r = 0.33, P = 0.03). CONCLUSION PD-L1 expression is paradoxically associated with improved survival in MMR-proficient CRC.

High Myeloperoxidase Positive Cell Infiltration in Colorectal Cancer Is an Independent Favorable Prognostic Factor

Background Colorectal cancer (CRC) infiltration by adaptive immune system cells correlates with favorable prognosis. The role of the innate immune system is still debated. Here we addressed the prognostic impact of CRC infiltration by neutrophil granulocytes (NG). Methods A TMA including healthy mucosa and clinically annotated CRC specimens (n = 1491) was stained with MPO and CD15 specific antibodies. MPO+ and CD15+ positive immune cells were counted by three independent observers. Phenotypic profiles of CRC infiltrating MPO+ and CD15+ cells were validated by flow cytometry on cell suspensions derived from enzymatically digested surgical specimens. Survival analysis was performed by splitting randomized data in training and validation subsets. Results MPO+ and CD15+ cell infiltration were significantly correlated (p<0.0001; r = 0.76). However, only high density of MPO+ cell infiltration was associated with significantly improved survival in training (P = 0.038) and validation (P = 0.002) sets. In multivariate analysis including T and N stage, vascular invasion, tumor border configuration and microsatellite instability status, MPO+ cell infiltration proved an independent prognostic marker overall (P = 0.004; HR = 0.65; CI:±0.15) and in both training (P = 0.048) and validation (P = 0.036) sets. Flow-cytometry analysis of CRC cell suspensions derived from clinical specimens showed that while MPO+ cells were largely CD15+/CD66b+, sizeable percentages of CD15+ and CD66b+ cells were MPO−. Conclusions High density MPO+ cell infiltration is a novel independent favorable prognostic factor in CRC.

Early versus delayed cholecystectomy in patients with biliary acute pancreatitis

BACKGROUND In patients with biliary acute pancreatitis (AP), cholecystectomy is mandatory to prevent further biliary events, but timing of cholecystectomy remains a subject of ongoing debate. The objective of the present, retrospective study was to compare the outcomes of early (within 2 weeks after onset of disease) versus delayed cholecystectomy in patients with biliary AP. METHODS Between January 2000 and December 2005, 112 patients underwent cholecystectomy because of biliary AP. Thirteen patients were excluded from analysis because of necrotizing pancreatitis on the initial computed tomography. Thirty-two were operated within 14 days (group A) and 67 after a longer time period (group B). The primary end point of the study was the rate of biliary complications before cholecystectomy. RESULTS There were no differences regarding conversion rates to open surgery (6% vs 3%; P = .59), local (3% vs 4%; P = 1.00), or systemic complications (0% vs 3%; P = 1.00), and mean postoperative stay (4.7 vs 5.7 days; P = .40). Nevertheless, a greater rate of recurrent biliary pancreatitis was found in the group undergoing cholecystectomy later (0% vs 13%; P < .03). CONCLUSION The timing of cholecystectomy seems to have no clinically relevant effect on local or systemic complications, but delaying cholecystectomy is associated with an increase of biliary complications in patients with non-necrotizing biliary AP.

Laboratory markers predicting severity of acute pancreatitis

Abstract Acute pancreatitis (AP) is an inflammatory disease of highly variable severity, ranging from mild cases with low mortality to severe cases with high mortality. Numerous biomarkers have been studied as potential early predictors of the severity of this disease so that treatment can be optimally tailored to prevent complications. We aim to present and discuss the most relevant biomarkers for early severity assessment in AP that have been studied to date. We review the current literature on biomarkers that have been used to predict the severity in AP. C-reactive protein (CRP) is still considered to be the gold standard, with a cut-off value of 150 mg/ml 48 h after disease onset. Other markers, including procalcitonin (PCT) and interleukin 6 (IL-6) have been implemented in some hospitals, but are not used on a routine basis. Most other markers, including acute phase proteins (LBP, SAA, PTX3), cytokines (Il-8, TNF-a, MIF), activation peptides of pancreatic proteases (TAP, CAPAP, PLAP), antiproteases (AAT, a2M), adhesion molecules (ICAM-1, selectins, E-cadherin) and leukocyte-derived enzymes (PA2, PMN-E) have shown some promising results but have not been routinely implemented. Furthermore, new and interesting biomarkers (Copeptin, TRX-1, Ang-2, E-2) have shown good results, but more research is needed to determine if they could play a role in the future. Various reasons why new markers for disease severity have not been adopted in daily routine include low accuracy, cumbersome laboratory techniques and high cost. Despite these difficulties, research is still very active in finding new markers to predict the severity of AP.

Incarcerated obturator hernia–laparoscopic repair with intraoperative view of the corona mortis

Obturator hernias are a rare form of abdominal wall hernias. We present a case of a patient with an obturator hernia diagnosed by the classical signs of lower abdominal pain, a positive Howship–Romberg sign (painful internal rotation of the hip) and a computed tomography scan showing a herniated loop of small bowel. During the emergency laparoscopic hernia repair (transabdominal preperitoneal approach) a variant vessel, the corona mortis, was detected.

Absence of myeloperoxidase and CD8 positive cells in colorectal cancer infiltrates identifies patients with severe prognosis

Colorectal cancer (CRC) infiltration by cells expressing myeloperoxidase (MPO) or CD8 positive T lymphocytes has been shown to be independently associated with favorable prognosis. We explored the relationship occurring between CD8+ and MPO+ cell CRC infiltration, its impact on clinical-pathological features and its prognostic significance in a tissue microarray (TMA) including 1,162 CRC. We observed that CRC showing high MPO+ cell infiltration are characterized by a prognosis as favorable as that of cancers with high CD8+ T cell infiltration. However, MPO+ and CD8+ CRC infiltrating cells did not synergize in determining a more favorable outcome, as compared with cancers showing MPOhigh/CD8low or MPOlow/CD8high infiltrates. Most importantly, we identified a subgroup of CRC with MPOlow/CD8low tumor infiltration characterized by a particularly severe prognosis. Intriguingly, although MPO+ and CD8+ cells did not co-localize in CRC infiltrates, an increased expression of TIA-1 and granzyme-B was detectable in T cells infiltrating CRC with high MPO+ cell density.

OX40 expression enhances the prognostic significance of CD8 positive lymphocyte infiltration in colorectal cancer

Background OX40 is a TNF receptor family member expressed by activated T cells. Its triggering by OX40 ligand promotes lymphocyte survival and memory generation. Anti-OX40 agonistic monoclonal antibodies (mAb) are currently being tested in cancer immunotherapy. We explored the prognostic significance of tumor infiltration by OX40+ cells in a large colorectal cancer (CRC) collective. Methods OX40 gene expression was analyzed in 50 freshly excised CRC and corresponding healthy mucosa by qRT-PCR. A tissue microarray including 657 clinically annotated CRC specimens was stained with anti-OX40, -CD8 and -FOXP3 mAbs by standard immunohistochemistry. The CRC cohort was randomly split into training and validation sets. Correlations between CRC infiltration by OX40+ cells alone, or in combination with CD8+ or FOXP3+ cells, and clinical-pathological data and overall survival were comparatively evaluated. Results OX40 gene expression in CRC significantly correlated with FOXP3 and CD8 gene expression. High CRC infiltration by OX40+ cells was significantly associated with favorable prognosis in training and validation sets in univariate, but not multivariate, Cox regression analysis. CRC with OX40high/CD8high infiltration were characterized by significantly prolonged overall survival, as compared to tumors with OX40low/CD8high, OX40high/CD8low or OX40low/CD8low infiltration in both uni- and multivariate analysis. In contrast, prognostic significance of OX40+ and FOXP3+ cell infiltration was not enhanced by a combined evaluation. Irrespective of TNM stage, CRC with OX40high/CD8high density infiltrates showed an overall survival similar to that of all stage I CRC included in the study. Conclusions OX40high/CD8high density tumor infiltration represents an independent, favorable, prognostic marker in CRC with an overall survival similar to stage I cancers.

Swelling of the right thigh for over 30 years-The rare finding of a De Garengeot hernia.

Highlights • Inguinal/femoral swelling can obtain the appendix.• De Garengeot hernia needs to be considered as differential diagnosis in all femoral hernia.• A femoral hernia in a woman can obtain the appendix in an open processus vaginalis.• Sonography is a valid diagnostic tool for De Garengeot hernia.

Cancer‐associated retinopathy as the leading symptom in colon cancer

Cancer‐associated retinopathy (CAR) is a rare paraneoplastic visual syndrome. Its early detection may lead to the diagnosis of the causative malignancy. As many different types of malignancies are known to be associated with CAR, it is important that clinicians are aware of the phenomenon of CAR.

Acute thyroid swelling and elevated C reactive protein.

A 34-year-old lady presented with a painful swelling of the left thyroid lobe since 1 week and elevated C reactive protein (CRP) above 100 mg/L. An ultrasound examination revealed a thyroid cyst with partly solid component, suitable with a haemorrhage into a cyst. The serum thyroid stimulating hormone (TSH), as well as peripheral thyroid hormones, was in the normal range. The acute swelling could be well explained by a haemorrhage, but not an elevated CRP. Her medical history was uneventful apart from a tooth extraction 2 weeks ago due to an infection. Therefore, our hypothesis was a haemorrhage into a pre-existing thyroid cyst during bacteraemia caused by the tooth infection. Conservative treatment with the aim of delayed hemithyreoidectomy failed due to a second episode of haemorrhage. During surgical resection pus drained out of the cyst and the histological report afterwards confirmed our tentative diagnosis. The patient was discharged 2 days later.