Diagnose: IOBT - FOB test - immunochromatographic fecal occult blood test - ontlastingstest goedkoper en minder belastend voor de patiënt in het opsporen en vaststellen van darmkanker

28 januari 2021: zie ook dit artikel: https://kanker-actueel.nl/bloedtest-kan-vroeg-darmkanker-en-voorstadia-van-darmkanker-kwaadaardige-darmpoliepen-zichtbaar-maken-met-een-betrouwbaarheid-van-100-procent-voor-darmtumoren-en-75-procent-voor-kwaadaardige-poliepen-van-1-cm.html
4 december 2018: lees ook dit artikel:

https://kanker-actueel.nl/NL/coloscopie-met-g-eye-balloon-techniek-ontdekt-veel-beter-kwaadaardige-darmpoliepen-28-procent-dan-standaard-coloscopie.html

15 juli 2012: Hoewel de FOBT ontlastingstest een aantal voordelen heeft is ook deze niet 100% betrouwbaar. In Nederland wordt als proef al enige jaren in sommige ziekenhuizen ook aanvullend gevraagd naar persoonlijke factoren: Project: Risk profiling for colon cancer. Op basis van de resultaten uit dit onderzoek wordt in 2013 een bevolkingsonderzoek naar darmkanker ingevoerd: Bevolkingsonderzoek darmkanker

16 september 2005: Bron: Pol Merkuriusz Lek. 2004 Dec;17(102):579-82 en WCOG 2005: Abstract DR 0527. Presented Sept. 13, 2005.

Een nieuwe immuunchromatografische fecal occult blood test (IOBT of FOB afgekort) (is een simpele test van de ontlasting) is veel gevoeliger dan de standaard gebruikte bloedtest (GOBT) voor het opsporen van darmkankers en ook beter voor het opsporen van voorstadia van darmkanker, blijkt uit een 1 op 1 vergelijking in twee grote studies. 1 studie is gepubliceerd in 2004 en blijkt een andere grote studie dezelfde resultaten te geven. De FDA heeft deze test volgens de schrijver van het artikel uit Medscape reeds goedgekeurd voor gebruik. De Spaanse onderzoeksleider dr. Enrique Quintero van de meest recente studie beveelt na deze studieresultaten deze test aan als voortaan standaard te gaan gebruiken voor iedereen die in de risico groep zit voor het krijgen van een vorm van darmkanker.

Hier een studiecitaat letterlijk vertaald uit de meest recente studie:
De IOBT test was veel gevoeliger en betrouwbaarder dan de GOBT test, met een gevoeligheid van 50% voor de opsporing en vaststelling van gevorderde darmkanker van het type adeno, 100% voor dikke darmkanker en 58% voor gevorderde neoplasia is kwaadaardige poliepen bevestigd met een colonoscopie. In vergelijking, de gevoeligheid van de GOBT test was 9% voor opsporing van gevorderde adeno darmkanker, 23% voor dikke darmkanker en 12% voor gevorderde neoplasia bevestigd door colonoscopie. Deze superieure gevoeligheid was niet verkregen ten koste van de specificiteit. Beide testen hadden een specificiteit van 92% of meer voor de opsporing en vaststelling van elk van genoemde condities bevestigd door colonscopie met voor de IOBT test 2 tot 5% minder specificiteit dan voor de GOBT test. Ook de Poolse studie, abstract zie hieronder, wijst op hoog significant betere resultaten voor de FOB test. We vragen ons wel af of deze test al in Nederlandse ziekenhuizen wordt uitgevoerd en of deze test wellicht een alternatief kan zijn voor het grote bevolkingsonderzoek naar dikke darmkanker waar nu heel veel geld voor wordt uitgegeven om te onderzoeken of dat wenselijk is. De IOBT test is veel gevoeliger, stukken goedkoper en veel minder belastend voor de patiënt. Wat willen we nog meer. Achtereenvolgens het abstract van de Poolse studie en daronder artikel uit Medscape van de meest recente Spaanse studie.

[Evaluation of usefulness of faecal occult blood test. Prospective screening study in patients with colorectal neoplasia]

[Article in Polish]

Banaszkiewicz Z, Jawien A, Jarmocik P, Tojek K, Jankowski M, Switonski M.
Klinika Chirurgii Ogolnej Akademii Medycznej w Bydgoszczy. banaszkiewicz@mediclub.pl

High incidence of colorectal cancer (CRC), good treatment outcome in case of surgery performed at an early stage of the disease, and a simple, low cost and quick diagnostic test, encourage the common use of screening for CRC. The aim of the study was to examine the efficacy of immunochromatographic faecal occult blood (FOB) testing in screening for early colorectal cancer.

MATERIAL AND METHODS: A total of 346 subjects with abdominal symptoms of unclear etiology were included to the study. Patients with diagnosed CRC, clinical symptoms suggesting CRC or those with family history of CRC were excluded from the study. All subjects had FOB testing done. All were subjected to sigmoidoscopy, no matter what the result of the screening test was. The sensitivity and specificity of the screening test for CRC was evaluated.

RESULTS: The total of 342 subjects aged 29-68 years (median 59 yrs), including 189 (58%) females and 153 (42%) males, were eventually qualified for the study. Colorectal pathology was found in 117 subjects (34.6%). Out of 62 patients with positive tests, 55 (89%) had a colorectal disorder diagnosed during sigmoidoscopy. The results were false positive in 7 cases. Colorectal neoplasia was recognized in 33 cases. These were neoplastic polyps (23) and adenocarcinoma (10). The great majority of neoplastic conditions were found in FOB positive subjects. The sensitivity of the test was 90%, while its specificity reached 84%. Diagnostic accuracy was 84%. Positive and negative predictive values were 15% and 99% respectively.

CONCLUSIONS: FOB testing appears highly sensitive and specific for colorectal cancer in patients with unclear abdominal symptoms.

Publication Types:
Validation Studies

Een artikel over deze nieuwe diagnose techniek gepubliceerd bij Medscape n.a.v. een recente studiepublicatie:

PMID: 15771126 [PubMed - indexed for MEDLINE]
Immunochromatographic Test Superior to Gold Standard for Colorectal Cancer Screening

Alison Palkhivala
Sept. 14, 2005 (Montreal) — A new immunochromatographic fecal occult blood test (IOBT) is far more sensitive than the standard guaiac-based fecal blood test (GOBT) for detecting colorectal cancer as well as precancerous states, according to a head-to-head comparison.

"This immunochemical test should be considered the first-choice fecal occult blood test for screening for colorectal cancer in the average-risk population," presenter Enrique Quintero, MD, told Medscape. He is chief of the gastroenterology department at the Hospital Universitario des Canarias, La Laguna, Tenerife, Spain.

Dr. Quintero and colleagues compared the IOBT, which was developed in Japan and is called OC-Light, directly with the current standard GOBT (Hemo-Fec). Their goal was to determine which test had the most sensitivity and specificity for detecting colorectal cancer and precancerous states compared with colonoscopy. He presented their findings in a poster here at the annual meeting of the World Congress of Gastroenterology.

"It's very easy to take a sample [using the IOBT]," said Dr. Quintero. "You collect the sample in a little bottle and put a strip inside. If you get one blue band, the test is negative, if you get a second band, that means the test is positive." In Europe, the test costs about 3.00 Euros.

Between July 2003 and April 2005, the investigators randomly selected 2,650 individuals aged 50 to 75 years from the Social Security Register of the Canary Islands for participation in the study. They excluded all those with regular use of nonsteroidal anti-inflammatory drugs or anticoagulants, recent history of screening for colorectal cancer or digestive tract bleeding, and a family or personal history of colorectal cancer, inflammatory bowel disease, or coagulopathy. The remaining 2,020 participants, considered to represent a population at average risk for colorectal cancer, were asked to take the GOBT and IOBT and were also invited to undergo a colonoscopy. Of these patients, 1,559 (77%) completed both fecal occult blood tests.

Overall, 8.4% of patients had positive IOBT test results and 3.8% had positive GOBT test results. An additional 1.9% of patients had positive results on both tests. Colonoscopy was performed in 154 of the 161 patients who had positive results on either of these tests and on 222 of the 1,398 patients who were negative for both tests.

Of the patients with a positive fecal occult blood test, 26% were found upon colonoscopy to have advanced adenoma, and 9% were found to have colorectal cancer. In contrast, of patients with a negative fecal occult blood test, 2% had advanced adenoma, and none had colorectal cancer. Of the 14 patients with colorectal cancer, six had early-stage disease.

The IOBT test was far more sensitive than the GOBT test, with a sensitivity of 50% for the detection of advanced adenoma, 100% for colorectal cancer, and 58% for advanced neoplasia, compared with colonoscopy. In contrast, the sensitivity of GOBT was 9% for detection of advanced adenoma, 23% for colorectal cancer, and 12% for advanced neoplasia compared with colonoscopy. This superior sensitivity was not obtained at the expense of specificity. Both tests had a specificity of 92% or more for the detection of each of these conditions compared with colonoscopy, with IOBT 2% to 5% less specific than GOBT.

"And this was a study done with one-time screening," Dr. Quintero told Medscape. "That means that if you repeat the test every year or two, the sensitivity...is going to be much higher."
The relative risk for advanced neoplasia in patients with positive results on a fecal occult blood test was 4.8 for the GOBT compared with 25.7 for the IOBT.
"We have to change our test for screening colorectal cancer," said Dr. Quintero. He added that the IOBT has already been approved by the Food and Drug Administration and is available in the U.S.

WCOG 2005: Abstract DR 0527. Presented Sept. 13, 2005.

Reviewed by Gary D. Vogin, MD