What is the likelihood of a malignancy being misdiagnosed as haemorrhoids, even after an anoscopy is performed?

Hi @cpg firstly, Im sorry to hear about your ordeal! Piles are abnormally swollen blood vessels towards the end of the colorectal tract. They are actually very common although most patients tend to delay seeking medical attention until they bleed or cause pain. Piles tend to be a chronic recurring condition, and factors such as increased abdominal pressure from constipation (straining to pass motion) or prolonged cough can contribute. If you recently had either of these before the relapse, that could be a cause and the best way to find out would be to visit your GP for an examination.

Colonoscopes are an effective method to diagnose Piles and also to differentiate them from cancer (in fact they are considered the "gold standard" for cancer diagnosis), as the specialist directly examines the entire colorectal region using high resolution scope devices and takes biopsies of any suspicious lesions (a "bite" using the scope, whereby cells are examined under the microscope). Furthermore, cancers are very rare in individuals your age unless you have many blood-related relatives that had colon or other related cancers at an early age.

That being said, if you experience any loss of weight/appetite, narrow or "pencil thin" stools, low energy/giddiness, or repeat episodes of blood loss, it would be prudent to arrange an early review with the specialist that performed the scope for you in order to have another detailed discussion. Hope this helps!