Tracheobronchial Polyflex stents for the management of benign refractory hypopharyngeal strictures.

AIM: To describe a modified technique for placement of a tracheobronchial self-expanding plastic stent (SEPS) in patients with benign refractory hypopharyngeal strictures in order to improve dysphagia and allow stricture remodeling. METHODS: A case series of four consecutive patients with complex hypopharyngeal strictures after combined therapy for laryngeal cancer, previously submitted to multiple sessions of dilation without lasting improvement, is presented. All patients underwent placement of a small diameter and unflared tracheobronchial SEPS. Main outcome measurements were improvement of dysphagia and avoiding of repeated dilation. RESULTS: The modified introducer system allowed an easy and technically successful deployment of the tracheobronchial Polyflex stent through the stricture. All four patients developed complications related to stent placement. Two patients had stent migration (one proximal and one distal), two patients developed phanryngocutaneous fistulas and all patients with stents in situ for more than 8 wk had hyperplastic tissue growth at the upper end of the stent. Stricture recurrence was observed at 4 wk follow-up after stent removal in all patients. CONCLUSION: Although technically feasible, placement of a tracheobronchial SEPS is associated with a high risk of complications. Small diameter stents must be kept in place for longer than 3 mo to allow adequate time for stricture remodeling.

Decreased Toll-interacting protein and peroxisome proliferator-activated receptor γ are associated with increased expression of Toll-like receptors in colon carcinogenesis.

BACKGROUND: Animal data suggest that Toll-like receptors (TLR) may play an important role in colon carcinogenesis. Studies in humans to support that hypothesis are scarce. AIM: To evaluate the expression of TLR2, TLR4 and TLR5, and the expression of several other related molecules, in different human colonic lesions. METHODS: Colon biopsy samples from normal mucosa, normal mucosa adjacent to lesion, adenoma or sporadic carcinoma were obtained from 35 consecutive patients undergoing colonoscopy. Quantification of TLR2, TLR4, TLR5, Toll-interacting protein (TOLLIP), peroxisome proliferator-activated receptor γ (PPAR-γ), nuclear factor κB, tumour necrosis factor (TNF) α, cyclooxygenase (COX) 1 and 2 mRNA was performed by real-time reverse transcription PCR. TLR2, TLR4 and TLR5 protein expression was quantified by immunohistochemistry. RESULTS: When compared with normal mucosa (1.0 arbitrary unit (AU)), adjacent normal mucosa presented higher expression of COX-2 (1.86±0.3 AU, p=0.01) and TNFα (1.44±0.18 AU, p=0.04) and lower TOLLIP expression (0.75±0.05 AU, p=0.004). Adenomas and carcinomas presented higher expression of COX-2 (1.63±0.27 and 1.38±0.14 AU, p=0.03 and p=0.05, respectively) and lower expression of TOLLIP (0.44±0.04 AU, p<0.001), with diffuse and higher TLR protein expression (p<0.001). Carcinomas also expressed higher TLR2 (2.31±0.32 AU, p=0.006) and lower PPAR-γ (0.56±0.12 AU, p=0.003). There was a trend towards decreased TOLLIP (p<0.001) and PPAR-γ (p=0.05) from normal mucosa to adenoma/carcinoma. CONCLUSIONS: Persistently positive TLR expression and lower expression of TLR inhibitors was associated with higher TLR protein levels throughout the spectrum of lesions of colon carcinogenesis. Increasing activation of these receptors by bacteria may play a crucial role in colon carcinogenesis and tumour progression.