Patient guide · 5 min read
Cytosponge cell collection, a swallowed sponge-on-a-string that samples oesophageal cells for Barrett’s screening.
The Cytosponge is a swallowed capsule containing a compressed sponge on a thread. Once in the stomach, the capsule dissolves and the sponge expands and is pulled back up, collecting oesophageal cells. Combined with TFF3 immunostaining it screens for Barrett’s oesophagus without endoscopy.
Key facts
- 01
Definition
A swallowed sponge-on-a-string for oesophageal cell sampling.
- 02
No endoscopy or sedation
Performed awake, in clinic, without a scope or sedative.
- 03
TFF3 immunostaining
Cells are stained for trefoil factor 3, a marker of Barrett’s epithelium.
- 04
Positive result triggers gastroscopy
A positive TFF3 result is followed by endoscopy for confirmation.
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Nurse-led, 10 minutes
A short, nurse-delivered procedure in an outpatient setting.
- 06
Endorsed by NHS trials
Backed by the BEST3 and DELTA Barrett’s screening trials.
Preparation and procedure
From referral to result — what happens, in order.
A nurse-led ten-minute appointment, with the result back inside two weeks.
- 01
Step 1
GP or gastro referral
Referral from your GP or a gastroenterologist to confirm the test is appropriate.
- 02
Step 2
Fast for 4 hours before the test
Nothing to eat or drink for four hours before the appointment.
- 03
Step 3
Capsule swallowed with water
You swallow a small capsule containing a compressed sponge, on a thread.
- 04
Step 4
7-minute wait
The capsule dissolves in the stomach and the sponge expands over about seven minutes.
- 05
Step 5
Sponge withdrawn on the string
The nurse gently pulls the sponge back up, collecting oesophageal cells on the way.
- 06
Step 6
Sample sent for TFF3 immunostaining
The sponge is sent to a specialist lab for TFF3 immunocytochemistry.
- 07
Step 7
Result within 2 weeks
A written result is typically available within two weeks.
What it shows
What the Cytosponge can detect.
The sponge samples cells across the oesophagus. TFF3 immunostaining then flags the columnar cells that define Barrett’s oesophagus.
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Barrett’s oesophagus (TFF3+)
TFF3-positive cells suggest columnar Barrett’s epithelium.
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Reflux oesophagitis
Cellular changes consistent with acid-driven inflammation.
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Squamous cell atypia
Atypical squamous cells that warrant further assessment.
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Glandular dysplasia
Dysplastic glandular cells that need endoscopic confirmation.
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Reassuring negative result
A TFF3-negative sponge with adequate cell yield is reassuring.
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Inadequate sample (repeat)
Occasionally the yield is insufficient and the test is repeated.
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Concomitant candida
Fungal elements may be picked up alongside the target cells.
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Red flag: TFF3+ with dysplasia — urgent gastroscopy + surveillance pathway
A positive result with dysplasia moves you onto an urgent endoscopic pathway.
Next steps
What happens after the result.
The pathway depends on whether the sponge is TFF3-negative, TFF3-positive, or shows dysplasia on subsequent endoscopy.
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Reassurance if TFF3 negative
A negative result with adequate cellularity is a reassuring end-point.
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Gastroscopy for TFF3-positive result
A positive TFF3 result is confirmed by upper GI endoscopy with biopsies.
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Barrett’s surveillance pathway
Confirmed Barrett’s enters an interval endoscopic surveillance programme.
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Endoscopic radiofrequency ablation
RFA is considered for dysplastic Barrett’s.
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Endoscopic mucosal resection (EMR)
EMR removes visible dysplastic or early neoplastic lesions.
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Anti-reflux therapy optimisation
PPI dose and lifestyle measures are optimised alongside surveillance.
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Anti-reflux surgery discussion
Fundoplication or magnetic sphincter augmentation may be considered.
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MDT review for high-grade dysplasia
High-grade dysplasia is discussed by an upper GI MDT.
Red flags
When the sponge isn’t the right test.
The Cytosponge is a screening tool. Alarm features, high-grade disease and prior anatomical problems all bypass it in favour of endoscopy.
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Dysphagia
Difficulty swallowing warrants urgent endoscopy rather than a sponge test.
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Weight loss
Unintentional weight loss with reflux symptoms needs urgent gastroscopy.
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Iron deficiency anaemia
New iron deficiency anaemia is an alarm feature for upper GI pathology.
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Post-radiotherapy stricture
Prior radiotherapy strictures make sponge withdrawal unsafe.
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High-grade dysplasia
HGD requires endoscopic assessment and MDT-led management.
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Adenocarcinoma on gastroscopy
Confirmed adenocarcinoma moves you to the cancer pathway.
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Non-adherence to surveillance
Missing surveillance intervals raises the risk of progression going undetected.
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Failed swallow (capsule retained)
Rarely the capsule is retained — clinical review is required.
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Concomitant reflux with alarm symptoms
Reflux plus any alarm feature bypasses screening in favour of endoscopy.
Sources
What this guide is built on.
Reviewed by Pulse Atlas Editorial Board (). Last reviewed 2026-07-30. Next review 2027-07-30.
Frequently asked
Everything patients ask about the Cytosponge.
What the sponge is, who it is for, and what happens with a positive result.
-
What is the Cytosponge?
The Cytosponge is a swallowed gelatin capsule containing a compressed sponge on a thread. In the stomach the capsule dissolves, the sponge expands to about 3 cm, and the nurse withdraws it on the string — collecting oesophageal cells on the way up.
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Is the Cytosponge safe?
Yes. Large trials including BEST3 and DELTA report the sponge is well tolerated, with a very low rate of complications. The main discomfort is a brief gag on withdrawal.
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Who is the Cytosponge for?
Adults with chronic reflux (typically over five years of symptoms or long-term PPI use) whose risk of Barrett’s oesophagus is elevated but who do not have alarm features. Anyone with dysphagia, weight loss or anaemia needs gastroscopy instead.
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What does TFF3 stand for?
Trefoil factor 3 — a protein expressed by the columnar cells of Barrett’s epithelium. Staining the retrieved cells for TFF3 makes Barrett’s cells stand out against normal squamous cells.
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How long does the procedure take?
Around ten minutes in total. The capsule is swallowed, there is a seven-minute wait for the sponge to expand, and the sponge is then withdrawn in a few seconds.
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What happens if the test is positive?
A TFF3-positive result is followed by upper GI endoscopy with biopsies to confirm Barrett’s oesophagus and to characterise any dysplasia — which then determines surveillance intervals or treatment.
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In practice, in London
Booking cytosponge cell collection privately in London — what actually happens
With cytosponge cell collection, the London question is usually about report turnaround and the radiologist reading it — not whether the scan is available. The NHS route for cytosponge cell collection is thorough, but the queue is real. Most patients we speak with have been told to expect anywhere from a handful of weeks to several months, depending on their local trust and how the referral is graded. Going private in London usually collapses that window to a matter of days — often the same week if the diary allows. It isn’t about jumping a queue so much as buying time back while you still have the flexibility to plan around it.
A typical private booking for cytosponge cell collection in London starts with a consultant conversation — sometimes in person on Harley Street or Marylebone, sometimes on video if that suits better. Any imaging or diagnostics happen at a nearby CQC-registered facility, and reports usually land within 24 to 72 hours. The whole loop, from first call to written report, is often done inside a fortnight. For cytosponge cell collection specifically, the difference between a routine report and a sub-speciality read is where private care earns its keep.
We’re careful about what a private pathway for cytosponge cell collection can and can’t promise. It can compress a wait, put you in front of a subspecialist quickly, and get a proper report in your hands within a week. It can’t rewrite what the imaging or the bloods say. Setting that expectation up front tends to make the whole experience less stressful.