Archived Policies - Medicine


Fiberoptic Analysis of Colorectal Polyps

Number:MED201.022

Effective Date:05-01-2008

End Date:02-14-2014

Coverage:

This policy is no longer scheduled for routine literature review and update.

Fiberoptic analysis of colorectal polyps is considered experimental, investigational and unproven.

Description:

During a colonoscopy or sigmoidoscopy as a screening test for colorectal cancer, the physician must often decide which polyp should be removed for histologic diagnosis.  While hyperplastic polyps are considered benign without malignant potential, adenomatous polyps are thought to represent one of the earliest stages in the progression to a malignancy.  Identification of these premalignant lesions is considered one of the cornerstones of colorectal cancer prevention.  The physician must thus balance the time and potential morbidity of removing all polyps, many of which will be benign, versus removal of those polyps most likely to be adenomatous.  Recently a spectrophotometry technique has been developed as an adjunct to colonoscopy that is intended to distinguish between normal and precancerous tissue.  This system is based on the observation that benign and malignant tissue emits different patterns and wavelengths of fluorescence after exposure to a laser light.  One such device was approved by the U.S. Food and Drug Administration (FDA) in 2000, the Optical Biopsy System (SpectraScience, Minneapolis MN). This system consists of an optical fiber emitting a laser that is directed against three different regions of the same polyp.  The subsequent fluorescent signal is collected, measured, and analyzed by a proprietary system software, and classifies a polyp as "suspicious" (i.e., adenomatous) or "not suspicious" (i.e., hyperplastic).

The FDA-labeled indication reads as follows:

"The SpectraScience™ Optical Biopsy™ System is indicated for use as an adjunct to lower gastrointestinal endoscopy.  The device is intended for the evaluation of polyps less than one centmeter in diameter that the physician has not already elected to remove.  The device is only to be used in deciding whether such polyps should be removed (which includes submission for histological examination)."

Rationale:

The FDA approval was based on a prospective, non-randomized phase II study involving 101 subjects from five sites.  The data from this trial have not been published in a peer-reviewed journal but are available as an FDA summary of safety and effectiveness.  Patients who participated in the study had undergone a prior lower GI endoscopic procedure with at least one polyp identified and were referred for an additional colonoscopy exam, in which fiberoptic analysis of the polyps was performed.  At the time of the colonoscopy, the physicians documented whether or not the polyp was considered hyperplastic or adenomatous and whether or not they would remove the polyp.  The fiberoptic probe was then applied to three different portions of the polyp and a segment of normal adjacent mucosa.  The physician did not know the results of the analysis and thus the test did not affect patient treatment.  The effectiveness of the analysis was then calculated as its ability to correctly identify adenomatous polyps (i.e., sensitivity) and to correctly identify hyperplastic polyps (i.e., the specificity), either alone or in conjunction with the physician assessment.  The sensitivity and specificity of the physician assessment alone was 82.7% and 50%, respectively, compared to a combined sensitivity and specificity of 96.3% and 33%, respectively.  In other words, fiberoptic analysis identified additional adenomatous polyps that the physician had classified as hyperplastic and presumably would not have removed based on visual assessment alone.  This increase in sensitivity comes at the price of a decrease in sensitivity, as more hyperplastic polyps will undergo biopsy.  However, according to the FDA, the risk of taking biopsies of additional hyperplastic polyps is minimal.

The clinical significance of these results and their effect on patient management is difficult to interpret from the data presented.  It is not clear how the physician decided to select additional polyps for fiberoptic analysis (it is not entirely clear whether all polyps were analyzed and then underwent biopsy), or whether the same results could be obtained by simply randomly taking a biopsy of a subset of polyps that were considered hyperplastic on visual assessment.  While adenomatous polyps are considered premalignant lesions, the evolution to cancer is a slow process requiring seven to eight years, and thus the immediate removal of all adenomatous polyps is not required.  In addition, the finding of an adenomatous polyp serves as a marker that the patient should undergo more frequent endoscopic exams.   It is well known that the current practice of visual inspection of polyps will certainly miss some adenomatous polyps, but this lack of sensitivity is considered acceptable if at least one adenomatous polyp is identified and the patient undergoes more frequent screening.

An updated search of the MEDLINE database through July 2006 did not identify any new published articles that addressed the above limitations.  The only study identified was a feasibility study of fiberoptic analysis of normal, adenomatous and cancerous tissue in 11 patients.

Contract:

Each benefit plan, summary plan description or contract defines which services are covered, which services are excluded, and which services are subject to dollar caps or other limitations, conditions or exclusions. Members and their providers have the responsibility for consulting the member's benefit plan, summary plan description or contract to determine if there are any exclusions or other benefit limitations applicable to this service or supply. If there is a discrepancy between a Medical Policy and a member's benefit plan, summary plan description or contract, the benefit plan, summary plan description or contract will govern.

Coding:

None


Medicare Coverage:

The information contained in this section is for informational purposes only.  HCSC makes no representation as to the accuracy of this information.  It is not to be used for claims adjudication for HCSC Plans.

The Centers for Medicare and Medicaid Services (CMS) does not have a national Medicare coverage position.  Coverage may be subject to local carrier discretion.

A national coverage position for Medicare may have been developed or changed since this medical policy document was written.  See Medicare's National Coverage at <http://www.cms.hhs.gov>.

References:

FDA – Optical Biopsy System:  Summary of Safety and Effectiveness.  1999.  Food and Drug Administration – Center for Devices and Radiologic Health (2000 November 14).  <http://www.fda.gov>   

Mayinger, B., Jordon, M., et al.  Endoscopic light-induced autofluorescence spectroscopy for the diagnosis of colorectal cancer and adenoma.  Journal of Photochemistry and Photobiology (2003 April) 70(1): 13-20.

Mayinger, B.  Endoscopic fluorescence spectroscopic imaging in the gastrointestinal tract.  Gastrointestinal Endoscopy Clinics of North America (2004 July) 14(3): 487-505.

Fiberoptic Analysis of Colorectal Polyps.  Chicago, Illinois:  Blue Cross and Blue Shield Association Medical Policy Reference Manual (2005 January) Medicine 2.01.51.

Policy History:

5/1/2008          Policy reviewed without literature review; new review date only.  This policy is no longer scheduled for routine literature review and update.

11/15/2006      Revised/updated entire document

8/15/2006        New medical document

Archived Document(s):

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