Extent of field change in colorectal cancers with BRAF mutation.

INTRODUCTION: Sporadic colorectal cancers with BRAF mutations constitute two distinct subgroups of colorectal cancers. Recent studies have linked the presence of the BRAF mutation to a familial inheritance pattern. This was a proof-of-concept study that aimed to examine: (a) the extent of field change in sporadic colorectal cancers with BRAF mutation; and (b) the extent of resection margins required and the pattern of DNA mismatch repair protein loss in these tumours. METHODS: Eight microsatellite instability-high tumours with positive BRAF mutation from an existing histopathological database were selected for BRAF mutation and mismatch repair protein analysis. RESULTS: All the resection margins were negative for BRAF mutation. Three tumours had loss of MLH1 and PMS2 expressions, and five tumours had no protein loss. Six peritumoral tissues were negative and one was positive for BRAF mutation. CONCLUSION: The results suggest that any early field change effect is restricted to the immediate vicinity of the tumour and is not a pan-colonic phenomenon. Current guidelines on resection margins are adequate for BRAF mutation-positive colorectal cancers. Any suggestion of a hereditary link to these tumours is likely not related to germline BRAF gene mutations. The pattern of protein loss reinforces previous findings for the two subgroups of BRAF mutation-positive colorectal cancers.

Innovations in chronic anal fissure treatment: A systematic review.

A chronic anal fissure is a common perianal condition. This review aims to evaluate both existing and new therapies in the treatment of chronic fissures. Pharmacological therapies such as glyceryl trinitrate (GTN), Diltiazem ointment and Botulinum toxin provide a relatively non-invasive option, but with higher recurrence rates. Lateral sphincterotomy remains the gold standard for treatment. Anal dilatation has no role in treatment. New therapies include perineal support devices, Gonyautoxin injection, fissurectomy, fissurotomy, sphincterolysis, and flap procedures. Further research is required comparing these new therapies with existing established therapies. This paper recommends initial pharmacological therapy with GTN or Diltiazem ointment with Botulinum toxin as a possible second line pharmacological therapy. Perineal support may offer a new dimension in improving healing rates. Lateral sphincterotomy should be offered if pharmacological therapy fails. New therapies are not suitable as first line treatments, though they can be considered if conventional treatment fails.

Obstructive sleep apnoea (OSA) patterns in bariatric surgical practice and response of OSA to weight loss after laparoscopic adjustable gastric banding (LAGB).

INTRODUCTION: This study aims to evaluate the incidence of Obstructive Sleep Apnoea (OSA) in severely obese Asians and to study the impact of weight loss on OSA. MATERIALS AND METHODS: We report the results of routine preoperative Polysomnograms in 350 Asian patients undergoing bariatric surgery in our institute. Polysomnograms were repeated in 75 randomly selected patients with moderate to severe OSA after target weight loss with the laparoscopically placed adjustable gastric band (LAGB). RESULTS: The prevalence of OSA in obese Asians is high. Moderate OSA was found in 46% of patients and severe OSA was found in 33%. Severe OSA was significantly more in the Chinese (46%) compared to the Malays (29%) or Indians (21%) (P = 0.035). We identified other risk factors for severe OSA (male sex, higher body mass index and the presence of hypertension) but were unable to select identifying parameters for very low (<5%) likelihood of severe OSA such that routine sleep studies prior to bariatric surgery could be omitted. Apnoea Hypoapnoea Index (AHI) showed improvement of 50% at 20 kg excess weight loss with the cure of OSA in preoperatively severe cases (P <0.005). Mild to moderate cases reported similar improvements although a direct correlation could not be established. Desaturation events, apnoea episodes, work of breathing and subjective assessment of sleepiness scores and quality of life (QOL) showed improving trends, albeit not statistically significant. Similar improvements were seen in sleep architecture with increased rapid eye movement (REM) and stage 3 sleep. CONCLUSIONS: The incidence of OSA in Asians undergoing bariatric surgery is high. Routine sleep studies in Asian patients are justified. Weight loss brought about a significant improvement in AHI and continuous positive airway pressure requirements. LAGB placement should be considered a broadly effective therapy for sleep apnoea in the severely obese patient.