Rectoscopy with fine needle biopsyMedical editor Stein Gunnar Larsen MD
Oslo University Hospital
Rectoscopy is the most simple diagnostic examination for suspicion of rectal cancer or cancer in the anal canal. The examination is always combined with rectal exploration and possibly needle biopsy.
The examination is performed with a rectoscope, which is a stiff tube with a light source. With this, the rectum is inspected as well as the surrounding mucous membrane - usually about 15 cm up from the anal opening. Behind the rectum ampule, right inside the anal canal, there is a large angle in which it is difficult to see small changes. This must be assessed carefully by exploration.
During the examinations, biopsies can be taken.
- Suspicion of cancer or inflammation in the rectum
- Suspicion of cancer or inflammation of the anal canal
- Diagnose changes in the rectum
- Diagnose changes in the anal canal
- Biopsy taking
- Double balloon for inflating air into the colon
- Light source for rectoscope
- Gel for exploration
- Rectal suction
- Biopsy forceps
- Specimen glass with formalin
- Needle for fine needle biopsy and fine needle cytology
- The colon is emptied the day of the examination with enema 1-2 hours prior.
- The patient must fast for the last 6 hours before the exam but may drink fluids up to 2 hours prior in case short term sedation is necessary.
- The patient lies in the lithotomy position.
- Before endoscopy, a thorough exploration is performed.
- The rectoscope is lubricated and inserted into the rectum.
- The stick in the rectoscope used to ease insertion is removed.
- The scope is inserted further into the bowel.
- Air is inflated into the bowel to improve overview.
- If needed, surface or fine needle biopsies are taken.
- The biopsy needle is inserted into the lesion along the finger
- When the biopsy needle is released, the mandrin is first released followed by the needle 2.5 cm forward.
- The biopsy remains in a notch in the mandrin.
- The scope is retrieved with circular movements such that the entire bowel is inpected. Be aware of the "blind zone" behind.
- The exam takes about 5 minutes.
The patient is observed for:
- bleeding if a biopsy is taken
- pain (gas pains can be expected)
At the outpatient clinic, the patient may go home the same day. Test results are usually available after 1-4 weeks.
An appointment for possible further follow-up and treatment is made.