Why you always retrovert in the rectum

This is a 55 year old lady undergoing flexible sigmoidoscopy to investigate her PR bleeding. This lesion was found on retroverting the endoscope in the rectum. 
WHAT IS THE MOST LIKELY DIAGNOSIS?

■ Fibro-epithelial polyp

INCORRECT

■ Inflammatory polyp

INCORRECT

■ Haemorrhoid

Yes!

■ Adenocarcinoma

INCORRECT!

■ Squamous cell carcinoma

INCORRECT

explanation

The three anal vascular cushions (at 3, 7 and 11 O’clock) help with maintaining continence.  
When these cushions become abnormally enlarged, due to for example excessive straining (chronic constipation), age, or raised intra-abdominal pressure (such as pregnancy, chronic cough, or ascites), they become pathological.

Haemorrhoids are classified as follows: 

• 1st Degree Remain in the rectum
• 2nd Degree Prolapse through the anus on defecation but spontaneously reduce
• 3rd Degree Prolapse through the anus on defecation but require digital reduction
• 4th Degree Remain persistently prolapsed

After a flexible sigmoidoscopy has excluded a low colonic lesion, most cases can be managed conservatively by reassurance, preventing constipation and topical analgesia. 

Alternatively, 1st and 2nd degree haemorrhoids can be treated with rubber-band ligation (RBL). A surgical haemorrhoidectomy may be indicated in the case of 3rd degree and 4th degree haemorrhoids. The serious complication of hemorrhoidectomy is  anal stenosis which occurs after 2-4% of operations. However, I have the impression that this procedure is performed far less now than in the past but have not seen any data to actually confirm this impression.