From Churg-Strauss Syndrome to Eosinophilic Granulomatosis With Polyangiitis: A Historical Review of Nomenclature and Diagnostic Criteria.

ABSTRACT: Eosinophilic granulomatosis with polyangiitis (EGPA) is rare vasculitis syndrome that involves the skin and other organ systems manifesting as asthma, eosinophilia, and pulmonary infiltrates. The understanding of EGPA, previously known as Churg-Strauss Syndrome, has continued to evolve from its earliest documentation in the literature in 1951. Herein, we review key historical advances in the diagnosis, classification, and nomenclature of EGPA that have shaped our understanding of this protean disorder over time.

Lymphocyte-activation gene 3 in non-small-cell lung carcinomas: correlations with clinicopathologic features and prognostic significance.

Lymphocyte-activation gene 3 (LAG-3) modulates the tumor microenvironment through immunosuppressive effects. Its associations with clinicopathologic parameters and prognostic significance in non-small-cell lung carcinomas remain unclear. We examined LAG-3 expression in 368 resected non-small-cell lung carcinomas (including 218 adenocarcinomas and 150 squamous-cell carcinomas) using tissue microarrays, with normalization to CD8+ T-cell count (LAG-3/CD8 index), and correlated LAG-3, CD8, and LAG-3/CD8 index with clinicopathologic features, molecular status, and survival. LAG-3 expression in the immune cells (ranged 0.35-540.1 cells/mm²) was identified in 92% of non-small-cell lung carcinomas. In adenocarcinomas and squamous-cell carcinomas, LAG-3 expression correlated with CD8+ T-cell count and PD-L1 expression. In adenocarcinomas, high LAG-3 expression (defined as >median) was additionally associated with smoking history, high T stage, aggressive pathologic features (solid-predominant histologic pattern, lymphovascular invasion, and nodal metastasis), and lack of EGFR mutation. In the entire resected tumor cohort and in adenocarcinomas, high LAG-3 and LAG-3/CD8 index were each associated with worse overall survival. In squamous-cell carcinomas, high CD8 was associated with better overall survival. In an exploratory analysis of pretreatment samples from advanced non-small-cell lung carcinoma patients treated with pembrolizumab, high CD8 was predictive of improved overall and progression-free survival, while high LAG-3, but not high LAG-3/CD8 index, was associated with improved progression-free survival. In conclusion, the clinicopathologic correlations and prognostic impact of LAG-3 in non-small-cell lung carcinoma are histotype-dependent, highlighting differences in the immune microenvironment between adenocarcinomas and squamous-cell carcinomas. The predictive impact of LAG-3 warrants further investigation.

Eosinophilic granulomatosis with polyangiitis: Cutaneous clinical and histopathologic differential diagnosis.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare, but severe systemic vasculitis that can affect skin and other organ systems. Diagnostic criteria have evolved, and many attempts have been made to classify the vasculitides based on clinical and/or histopathologic features, with an aim to develop standardized criteria. According to the EGPA Consensus Task Force recommendations, EGPA is a syndrome of asthma, eosinophilia, pulmonary infiltrates, and extrapulmonary vasculitis (such as cutaneous involvement with purpura). Histopathologic evidence of vasculitis in EGPA may be associated with eosinophilic infiltration and/or perivascular granulomatous inflammation. We review clinicopathologic criteria of this enigmatic vasculopathy.

Pancreatic ductal adenocarcinoma: tumour regression grading following neoadjuvant FOLFIRINOX and radiation.

AIMS: In the adjuvant setting, when compared to gemcitabine, patients with pancreatic ductal adenocarcinoma (PDAC) treated with FOLFIRINOX (Folinic Acid, Fluorouracil, Irinotecan, and Oxaliplatin) show superior survival. In this study, we quantitatively assess the pathological tumour response to chemoradiation in pancreatectomy specimens and reassess guidelines for tumour regression grading. METHODS AND RESULTS: We evaluated 92 patients with borderline resectable/locally advanced PDAC following pancreatectomy and neoadjuvant treatment with FOLFIRINOX and radiation. Demographic data, CAP tumour regression grade (TRG) and overall survival (OS) were recorded. A quantitative analysis of residual tumour was performed on the slide with the highest tumour burden to derive a tumour-to-tumour bed ratio. On univariate analysis, only lymph node status (P = 0.043) and CAP TRG (P = 0.038) correlated with OS. Sixteen per cent of patients showed a complete pathological response. The optimal tumour-to-tumour bed ratio cut-point was 11.6%, and on a multivariate model was the only pathological parameter that correlated with OS (P = 0.016) (hazard ratio = 2.27). CONCLUSIONS: The high proportion of patients with PDAC showing complete and near-complete pathological responses supports the use of FOLFIRINOX and radiation in the neoadjuvant setting. Several traditional pathology parameters fail to predict OS in patients treated with chemoradiation, while a quantitative tumour-to-tumour bed ratio is a powerful predictor of OS. The data support a two-tiered approach to TRG based on tumour-to-tumour bed ratio, and quantitative analysis merits further consideration.