FIT References/Resource List

For more information about colorectal cancer, visit these web sites:
American Cancer Society: Statistics for 2007
American Cancer Society Detailed Guide: Colon and Rectum Cancer
Comparison Study: Brush-sampling Fecal Immunochemical Test with Guaiac-Based Fecal Occult Blood Test
Centers for Disease Control and Prevention: Colorectal Cancer Screening
MedlinePlus: Colorectal Cancer
National Cancer Institute: Colorectal Cancer Screening
Quest Diagnostics Patient Health Library


InSure® Fecal Immunochemistry Test (FIT) References of Improved or Superior Performance Compared to guaiac-based FOBT (Hemoccult ® Sensa®)

Chronological Timeline: | 2006 | 2005 | 2003

2006

Allison J.E., Lawson, M. Screening Tests for Colorectal Cancer: A Menu of Options Remains Relevant Current Oncology Reports 8: p.492-498.

  Page 494-495.  “The advantages of FIT over GT include the following:
 
  1. FITs have superior sensitivity and specificity
  2. FITs use antibodies specific for human globin and are, unlike GT, specific for colorectal bleeding and not affected by diet or medications.
  3. Some FITs can be developed by automated developers and readers. This innovation allows for management of large numbers of tests in a standardized manner with excellent quality assurance.
  4. There is evidence that FIT use improves patient participation in screening for CRC.
  5. New technology for FITs allows them to quantify fecal hemoglobin so that sensitivity, specificity and positivity rates can be adjusted in screening for colorectal neoplasia.

  See Page 496 Table: FIT Performance Characteristics.

 Lieberman, D.  Screening for Colorectal Cancer in Average-Risk  Populations  The American Journal of Medicine, Vol. 119, No 9, September 2006. p.728-735.

Page 730: “ There have bee many efforts to improve the operating characteristics of a stool-based occult blood test. Immunochemical FOBT ( iFOBT) uses antibodies specific for human globin in stool.  There is not need for dietary or drug restrictions, which might help improve adherence with testing.”
Page 731: “ There is some evidence that sampling with iFOBT can be conducted with 1or 2 stool samples because of improved selectivity compared with gFOBT. Test positivity rates for iFOBT (3%-5.9%) are acceptable for population-based screening.  Test sensitivity for cancer ranges from 60% to 85% and may be superior to gFOBT. The iFOBT is covered as a benefit for by Medicare beneficiaries and should be considered as an alternative to gFOBT.”

Young, G.  Molecular Approaches to Stool Screening for Colorectal Cancer
Current Colorectal Cancer Reports 2006, 2: p.30-35.
Page 32: Table 1:  Paired comparison of brush sampling FIT InSure with GFOBT   Hemoccult Sensa in 18 patients with colorectal cancer. The difference in sensitivity was 39% indicating that the FIT was significantly more sensitive for cancer than the GFOBT.

Page 32: “Fecal immunochemical tests (FIT) for hemoglobin are increasingly being considered in place of GFOBT. They are not affected by diet or drugs, differentiate upper from lower GI bleeding, and achieve better sensitivity for neoplasia without deterioration in specificity when compared with the sensitive guaiac tests such as Hemoccult.”

‘There have been few direct comparisons of FIT with GFOBT. Recent comparisons have shown either improved specificity, improved participation, or improved sensitivity.”
 “ InSure uses a brush to sample toilet bowl water around the stool, a method that has been shown to be both valid and preferred to the original stick-sampling method. One study showed 66% increase in population participation when using the brush-sampling FIT InSure; another showed a 90% increase.
On the basis of these observations, FIT should replace GFOBT as the simple, non invasive screening test of choice even though FIT cost $10 to $20 more per episode of testing.”
2006

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2006

Smith, A., Young, G. et al. Comparison of a brush-sampling fecal immunochemical test for hemoglobin with a sensitive guaiac-based occult blood test in detection of colorectal neoplasia. Cancer 2006; 107 (9) 2152-59.

Background: This Australian study, published in the journal CANCER, was conducted to determine if InSure, a brush-sampling fecal immunochemical test (FIT) improved- detection of significant neoplasia as compared Hemoccult® II Sensa®, a sensitive guaiac fecal occult blood test (GFOBT). The study was funded in part by Enterix, which did not participate in the data analysis nor influence the conclusions reached.

Method:  Patients sampled consecutive stools, at home, to complete both the InSure and the Hemoccult II Sensa tests. Study groups included a screening cohort (n=2,351) and a symptomatic diagnostic cohort (n=161). Patients with positive screening results – i.e., blood in the stool - were referred for colonoscopy to detect possible cancer or a significant adenoma. Following colonoscopy, the cancer and type of polyp were subsequently confirmed by histopathology.

Results: The InSure FIT demonstrated a true-positive result significantly more often in the presence of cancer (n=24, 87.5% vs. 54.2%) or significant adenoma (n=61, 42.6% vs. 23.0%) than did Hemoccult II Sensa. Of all stage I cancers (where the tumor is limited to the lining of the bowel wall), the InSure FIT was positive in 12 of 13 cases, compared to only 4 of 13 with the Hemoccult II Sensa (p=0.002).  The study results also showed that the InSure test was more accurate than the Hemoccult II Sensa in detecting lower gastrointestinal bleeding in early-stage lesions or significant adenomas. The bottom line is InSure detected bleeding due to early-stage colorectal cancers three times as often as Hemoccult II Sensa and bleeding due to significant (pre-cancerous) adenomas nearly twice as often as Hemoccult II Sensa.

Medscape CME: Fecal Immunochemical Test May Be Most Effective for At-Home Colon Cancer Screening

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2005

Allison, JE.   Colon Cancer Screening Guidelines 2005: The Fecal Occult Blood Test Option Has Become a Better FIT   Gastroenterology 2005 Vol. 129, No.2 p.745-748.

Page 745: “The fecal immunochemical tests (FIT) address many of the weaknesses of the GT (guaiac test). They have superior sensitivity and specificity. The application sensitivities for cancer are good (66%-82%) but for polyps >1 cm they are more modest; however, the use of a program of fecal occult blood test (FOBT) screening  in which screening is performed yearly or every other year may result in cumulative sensitivity of the program that is competitive with a program of a more sensitive test performed less frequently….. The FITs efficacy in decreasing colon cancer mortality and incidence has not been studied in randomized controlled trials but if the new screening tests are more accurate that GT (Hemoccult II) , their effectiveness need not be confirmed by randomized controlled trials because Hemoccult II’s ability to save lives from colorectal cancer has already been shown.”
Page 747: “ If, as it appears, the FIT has better performance characteristics than the GT (Hemoccult II), that is compelling evidence for recommending its use as the FOBT of choice in colon cancer screening programs.”

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2003

Smith, R et.al. American Cancer Guidelines for Early Detection of Cancer 2003, CA –A Cancer Journal for Clinicians 2003 vol.53 Number 1 page 34.

“ the Advisory Group concluded that the evidence showing improved specificity with immunochemical tests, and the lack of requirements to adhere to dietary restrictions prior to the test  was sufficiently persuasive to update the guideline statement for FOBT to include immunochemical tests.”

“ In comparison with the guaiac- based tests for the detection of occult blood, immunochemical tests are more patient friendly and are likely to be equal or better in sensitivity and specificity.”

Levin et.al, Emerging Technologies in Screening for Colorectal Cancer. Cancer A Cancer Journal for Clinicians 2003, pages 49-51.

Page 51 Advantages and Limitations of InSure:

  “Advantages of an immunochemical tests compared to guaiac based test include:
 
  • Improved specificity. Immunochemical tests will not react with non-human hemoglobin, vitamins, drugs, or peroxidase from food sources. InSure has also been shown to be non-reactive with blood from the upper gastrointestinal tract when bleeding is occult.
  • Potential increase in patient compliance, since no dietary restrictions are needed and since InSure requires collection from only two stool specimens and is performed by swirling a brush in the toilet water with the stool, it may be more acceptable to the consumer than current FOBT tests with their higher testing and stool handling requirements.

Cole, SR, Young, GP, Esterman, A, Cadd, B, Morcom, J.  A randomized trial of the impact of new faecal hemoglobin test technologies on population participation in screening for colorectal cancer. J Med Science 2003;10:117-22.

This study investigated the effect on participation in colorectal cancer screening of testing for blood products in stool using tests that remove restrictions (diet and medicine) and simplify collection (brush sampling). The study compared Hemoccult Sensa, Flexsure (which is now called Hemoccult ICT and InSure.
 
Page 117: “ The brush sampling faecal immunochemical test for hemoglobin (InSure) achieves the best participation rates by simplifying sampling and removing the need for restrictions of diet and drugs. Because participation in screening is vital to detection, this new technology should contribute to better detection of neoplasia at the population level.”
Page 121: “ It is noteworthy that combining removal of restrictions and simplification of sampling further enhances participation (increase in RR of 66%), indicating that both technological advances offered by the brush- sampling FIT.”

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