Paraneoplastic leukemoid reaction in a localised squamous cell oesophageal cancer with paracrine G-CSF production.

A 51-year-old-man presented with symptoms and baseline investigations suggestive of an infective process. Most strikingly, there was a pronounced neutrophil predominant leucocytosis. Lack of a clinical and biochemical response to empirical antibiotic therapy, prompted imaging for a deep-seated infective process, incidentally uncovering a gastro-oesophageal junction tumour. Resection of the tumour was followed by rapid resolution of the leucocytosis. He remains in clinical remission since tumour resection and adjuvant chemotherapy. Cancer-associated leukemoid reactions in non-disseminated tumours are rare. The role of polymorphonuclear (PMN) leucocytes both in the peripheral blood and the tumour itself is discussed herein. There is increasing recognition of the importance of the non-cancer cellular components of the tumour microenvironment. Myeloid suppressor cells are a subset of PMN leucocytes which play a role in tumour progression.The role of these cells and granulocyte colony-stimulating factor is highlighted in this case.

Clear cell sarcoma of the gastrointestinal tract and malignant gastrointestinal neuroectodermal tumour: distinct or related entities? A review.

Clear cell sarcoma is an uncommon sarcoma which rarely occurs as a primary tumour in the gastrointestinal tract (CCS-GIT). It shares common molecular genetic abnormalities with the more recently described entity, malignant gastrointestinal neuroectodermal tumour (GNET) but is distinguished by its morphological and immunohistochemical findings. The exact nosological relationship between these tumours continues to be debated. In this review, we present two cases of these rare neoplasms from our files and perform a statistical comparison of all published cases to determine if significant differences exist in their clinicopathological features and biological behaviour. Thirteen cases of CCS-GIT and 58 of GNET were included. CCS-GIT occurred more commonly in males (84.6% vs 46.6%, p = 0.01) and in an older age group (median 57 vs 33 years, p < 0.01). There was no significant difference in their location in the gastrointestinal tract, median tumour size and proportion of cases with an EWSR1-ATF1 vs EWSR1-CREB1 fusion. Median survival for CCS-GIT was 13.5 months and for GNET, 9.5 months (p = 0.78). There was no significant difference in the Kaplan-Meier survival curves for either time to first metastasis (p = 0.88) or overall survival (p = 0.18), including after controlling for tumour size using regression models. Our analysis confirms that aside from morphological variations between these tumours, they also exhibit epidemiological and clinical differences. Despite the prevalent perception that GNET is associated with a more aggressive clinical course, our findings indicate that there is no significant difference in their biological behaviour, although both clearly share a bleak prognosis. Further experience is awaited to determine optimal treatment strategies and whether CCS-GIT and GNET would differ in their response to various therapies.

Erdheim-Chester disease associated with a novel, complex BRAF p.Thr599_Val600delinsArgGlu mutation.

BRAF mutation testing to determine eligibility for treatment with vemurafenib was performed on archival skin lesions of a 54-year-old patient diagnosed with Erdheim-Chester disease (ECD) in 1999. Sanger sequencing of DNA extracted from a 2008 skin lesion identified two non-contiguous base substitutions in BRAF, which were shown by next-generation sequencing (NGS) to be located in the same allele. Due to its long-standing duration, molecular evolution of disease was possible; however, both Sanger and NGS of a 2000 skin lesion were unsuccessful due to the poor quality of DNA. Finally, droplet digital PCR using a probe specific for this novel mutation detected the complex BRAF mutation in both the 2000 and 2008 lesions, indicating this case to be ECD with a novel underlying BRAF p.Thr599_Val600delinsArgGlu mutation. Although well at present, molecular modelling of the mutant BRAF suggests suboptimal binding of vemurafenib and hence reduced therapeutic effectiveness.

A diagnostic conundrum: heterophilic antibody interference in an adrenocorticotropic hormone immunoassay not detectable using a proprietary heterophile blocking reagent.

CONTEXT: Heterophilic antibodies are a well-described interferent but poorly appreciated and are often not a recognized problem affecting most immunoassays. We describe for the first time heterophilic antibodies interference affecting an adrenocorticotropic hormone (ACTH) assay in a patient with Cushing's syndrome due to bilateral nodular adrenal hyperplasia. CASE: A 60-year-old retired female nurse underwent extensive invasive investigations, which were ultimately unnecessary, as a result of initial analytical interference in the ACTH assay, which could not be resolved using a proprietary heterophilic binding reagent. RESULTS: This case highlights the inherent difficulty of diagnosing Cushing's syndrome and the large emphasis placed on laboratory tests. The consequence of not initially identifying interference in this patient's laboratory test results led to unnecessary and costly investigations with potentially adverse outcomes. CONCLUSIONS: Clinicians and the laboratory community need to be continuously vigilant and view laboratory results with caution when they are inconsistent with the clinical picture. This approach is paramount, especially at a time of increasing automation and ever-diminishing scientist involvement in sample processing.

Gastric intraepithelial neoplasia in a Western population.

BACKGROUND AND STUDY AIMS: Descriptions of the natural history and endoscopic appearances of gastric dysplasia/intraepithelial neoplasia (IEN) that originate mainly from Europe. Currently, there are no Australian data available. We aimed to document endoscopic appearances and progression rates of gastric IEN and to determine the significance of indefinite for IEN. PATIENTS AND METHODS: This is a retrospective study, in which cases diagnosed with gastric IEN were identified between 2000 and 2009. Endoscopic appearances, progression rates to more advanced IEN or cancer, and long-term outcomes were recorded. RESULTS: A total of 160 cases with IEN (26.9% high grade, 57.5% low grade, 15.6% indefinite) were identified. The mean age was 67.8 years and 53.8% were men. Endoscopic lesions were polypoid in 29.4% and nonpolypoid in 70.6%. The most common location was the antrum (58.7%). Forty patients had an intervention and 76 underwent endoscopic follow-up only. Twenty-two cancers were diagnosed; three who had an intervention were diagnosed within 12 months, one with low-grade intraepithelial neoplasia developing a cancer after 9.9 years, and 13 undergoing surveillance only, were diagnosed with cancer within 12 months of index endoscopy. Five cases had cancer after a mean of 2.6 years. Forty-seven cases initially labelled as indefinite; following rereview 25 remained unchanged, 11 reclassified as negative for IEN, 10 as low grade, and one as high grade. Three of these cases developed cancer over the study period. CONCLUSION: We concluded that (a) majority of gastric IEN are associated with endoscopic lesions, (b) high rate of early cancer diagnosis was observed (c) rates of progression to cancer were lower than reported rates, and (d) indefinite for IEN is not innocuous requiring an expert pathologist's review.

Human epidermal growth factor receptor 2 testing in gastric carcinoma: issues related to heterogeneity in biopsies and resections.

AIMS: To assess human epidermal growth factor receptor 2 (HER2) status and heterogeneity using immunohistochemistry (IHC) and silver in-situ hybridization (SISH) in gastric carcinoma and dysplasia, and to correlate HER2 status between biopsy and resection specimens of gastric carcinoma. METHODS AND RESULTS: Immunohistochemistry for HER2 was performed in 178 cases of gastric carcinoma, and SISH in cases showing at least 1+ reaction. HER2 positivity [European Medicines Agency (EMA) guidelines] was identified in 20.2% of carcinomas and 12.9% of high-grade dysplasia, and HER2 heterogeneity noted in 50% and 33% of these cases, respectively. IHC negative/positive reactivity and SISH results were concordant in 96.2%. SISH amplification was seen in 35.3% of IHC 2+ and in a case with previously unrecognized staining pattern. Concordance of IHC HER2 status on biopsies and gastrectomies was seen in 74.1%. False negative IHC results on either the biopsy or gastrectomy were seen in 19.4% of HER2 amplified cases. CONCLUSIONS: Human epidermal growth factor receptor 2 status in gastric carcinoma is comparable to previous studies with good concordance between IHC and SISH; all IHC 2+ and unusual patterns should be assessed with ISH studies; heterogeneity of tumour HER2 overexpression/amplification is common with possible implications for HER2 testing; and HER2 overexpression appears sufficiently specific to be considered a potential diagnostic biomarker of dysplasia.