Perineurioma of the sigmoid colon

A 24-year-old man presented to the surgical outpatient clinic with a 1-year history of intermittent, painless, fresh rectal bleeding associated with defaecation. The blood was noticeable as streaks on the toilet paper. His bowel habit remained otherwise unchanged. He reported no weight loss or family history of bowel cancer. His medical history was unremarkable. On examination, there were no clinical features of anaemia, jaundice, cyanosis, clubbing, oedema or cervical lymphadenopathy. Proctoscopy revealed an internal haemorrhoid at the 7 o’clock position. Blood test results included a haemoglobin level of 158 g/L, mean corpuscular volume of 87.0 fL and mean corpuscular haemoglobin concentration of 331 g/L, all of which were within normal limits. On flexible sigmoidoscopy, a 3 mm polyp within the sigmoid colon was identified. This was a well-circumscribed, flat elevated lesion (Paris classification type 0–IIa) (figure 1). Its surface …