Epidermal growth factor receptor mutation testing: From conventional to real-time diagnosis of lung cancer.

Patients with non-small cell lung cancer (NSCLC) commonly harbor epidermal growth factor receptor (EGFR) mutation. Due to the complex disease pathology, early-stage diagnosis of patients with EGFR mutation is essential to make appropriate treatment decision. Tyrosine kinase inhibitors (TKIs) are commonly used for their treatment, but almost half of the patients with EGFR mutation do not respond to the available TKIs and develop acquired resistance owing to T790M mutation. The presence of T790M mutation also warrants a robust diagnostic method so as to allow clinicians to modify cancer treatment. Numerous diagnostic techniques for the detection of EGFR mutation, however, their performance and working profile variation necessitate a comparative evaluation for the selection of a better diagnostic method or an advanced combination of theirs. The present review compares various EGFR-mutation detection techniques such as Sanger sequencing, next-generation sequencing, and different polymerase chain reaction (PCR)-based methods. It also highlights the role of advanced PCR-based techniques, i.e., real-time or quantitative PCR and digital droplet PCR (ddPCR) for detecting EGFR mutations in NSCLC patients. ddPCR, when compared to other methods, shows enhanced sensitivity, superior reliability, and improved time and cost-effectiveness. Moreover, its ability to detect EGFR mutations including T790M, in both conventional (solid tissue biopsy samples) and nonconventional sample sources (blood, plasma, and urine samples), gives it an edge over other diagnostic techniques and support its integration in clinical practice setting.

Cyclooxygenase 2 mediates post-inflammatory colonic secretory and barrier dysfunction.

BACKGROUND AND AIMS: The colonic epithelium plays a key role in host defence. During colitis, epithelial function is impaired, leading to elevated bacterial translocation and exacerbation of inflammation. We previously documented perturbation of epithelial function, in terms of secretion and as a barrier to bacterial translocation, that persisted long after resolution of a bout of colitis in the rat. The mechanisms underlying the epithelial dysfunction are not completely understood. METHODS: Given the ability of prostaglandin (PG) D2 to suppress colonic epithelial secretion, we investigated the potential roles of this eicosanoid and of cyclooxygenase 2 (COX-2) in mediating post-colitis epithelial secretory and barrier dysfunction. RESULTS: Six weeks after induction of colitis with trinitrobenzene sulphonic acid, there was marked elevated synthesis of PGD2 and elevated COX-2 expression. Selective COX-2 inhibition abolished the increase in PGD2 synthesis. Colonic chloride secretory responses (in vitro) were significantly diminished relative to those in controls, a defect that was reversed by pre-exposure to a selective COX-2 inhibitor (celecoxib) but not to a selective COX-1 inhibitor (SC-560). The hyporesponsiveness was mimicked by pre-exposure of normal colonic tissue to PGD2, but not to its metabolite, 15-deoxy-Delta(12-14)PGJ2. The post-colitis rats exhibited a 10-fold increase in bacterial colonisation of the colon, and >3-fold increase in bacterial translocation. Twice daily treatment for one week with a selective COX-2 inhibitor (rofecoxib) did not affect bacterial colonisation but abolished the increase in bacterial translocation. CONCLUSIONS: These studies demonstrate an important role for COX-2, possibly via generation of PGD2, in mediating the prolonged epithelial secretory and barrier dysfunction after a bout of colitis in the rat.

Acute lymphoblastic leukemia presenting as breast mass.

We present here a 34 years female who presented with bilateral breast lumps as the initial manifestation of acute lymphoblastic leukemia. She was treated with consolidation chemotherapy and showed good response.