Special and Immunohistochemical Stains for Microscopic Evaluation of Esophageal and Gastric Tissue

POLICY NUMBER

L.2.04.433

DESCRIPTION

Disease of the esophagus and the stomach are frequently evaluated with the use of biopsies which are obtained during esophagogastroduodenoscopy (EGD). A large number of esophageal and gastric diseases, both benign and malignant, can be definitively diagnosed with the tissue taken and examined from the endoscopy procedure.

Hematoxylin and eosin (H&E) staining is the first stain in tissue-based microscopic diagnosis. Thin sections of tissue are stained with H&E to visualize the tissue morphology. Hematoxylin dye stains the cell nuclei blue and the eosin dye stains other structures pink/red. H&E staining provides excellent detail required for tissue-based diagnosis.

Special Stains and Immunohistochemistry

Special histochemical stains are called “special” because they are dyes used to stain particular tissues, structures or pathogens such as bacteria that may not be visible by routine H&E staining. Special stains can identify whether a substance is present or absent, where the substance is located in the tissue specimen, and frequently, how many or how much of a substance is present. There are special stains to identify bacteria, yeast and fungi; for connective tissue, muscle, collagen, lipid and fibrin; for nuclei acids; and multi-purpose stains to identify basement membranes, mucins, and various other cellular constituents. Examples of special stains used in the evaluation of esophageal and gastric tissue include, but are not limited to, alcian blue-periodic acid Schiff (AB-PAS) or other mucin stains, such as diastase-periodic acid Schiff (D-PAS), and special stains for Helicobacter pylori (H. pylori).

Immunohistochemistry (IHC) is a powerful tool for identifying substances and cells in tissue sections using the specificity of antigen-antibody reactions, where the antibody is linked to a colored indicator (stain) that can be seen with a microscope. More than 400 distinct antibody targets are currently available with varying sensitivity and specificity for a given target. A major use of IHC is to identify poorly differentiated malignant neoplasms (tumors) such as carcinoma, lymphoma, melanoma and sarcoma. Some IHC stains are useful in determining the primary site of a metastatic neoplasm, and others are used to guide specific therapies. Examples of IHC stains used in the evaluation of esophageal and gastric tissue include, but are not limited to, CDX-2; stains for neuroendocrine markers such as synaptophysin or chromogranin; CD3; stains which are used to characterize GIST tumor, enterochromaffin-like (ECL) cell hyperplasia/carcinoid tumor and stains for autoimmune disease.

POLICY

Special stains and IHC stains of esophageal, gastric and duodenal specimens may be considered medically necessary even though they have not been specifically requested by the treating provider, when after review of routine H&E stains, the pathologist deems them and ALL the following criteria are met:

• The services are medically necessary so that a complete and accurate diagnosis can be reported to the treating physician/practitioner;

• The results of the tests are communicated to and are used by the treating physician/practitioner in the treatment of the patient; and

• The pathologist documents in his/her report why additional testing was done.

Special stains or IHC stains of esophageal, gastric and duodenal specimens may be considered medically necessary for the following indications:

• Detection of H. pylori in an appropriate milieu when organisms are not seen on H&E stained slides;

• Evaluating atrophic gastritis for evidence of autoimmune etiology and for enterochromaffin-like (ECL) cell hyperplasia/carcinoid tumor

• Characterizing a carcinoma, lymphoma, melanoma or sarcoma

• Defining a GIST tumor and to distinguish it from mimics

• Ki-67 by IHC in grading of certain neuroendocrine tumors of the gut.

Routine use of special histochemical stains (special stains) and immunohistochemical (IHC) stains on esophageal, gastric and duodenal specimens is considered not medically necessary to determine if clinically meaningful intestinal metaplasia is present.

Special stains or IHC stains to determine the presence of H. pylori organisms, with the exception being cases of chronic gastritis when the organisms are not seen on the H&E slide, is considered not medically necessary.

The following special stains or IHC stains of esophageal, gastric and duodenal specimens are considered not medically necessary as a routine:

• Esophagus – fungal stains, trichrome, DPAS, CDX-2 or other mucin stains

• Gastric – AB-PAS, D-PAS, CDX-2 or other mucin stains, or special stains or IHC for H. pylori, or neuroendocrine markers such as synaptophysin or chromogranin

• Duodenum – AB-PAS, D-PAS, CD3, and trichrome, or other mucin stains

• Colon – CD3, p53 trichrome

• Hyperplastic polyps – Ki67, CK20, p53, CEA, BRAF

• Tubular or tubulovillous adenoma – Ki-67, CK20, CEA, p53, MMR.

Special stains or IHC stains are considered not medically necessary when performed as reflex templates or pre-orders prior to review of routine H&E stains by the pathologist.

Special stains or IHC stains without clinical evidence that the stain is actionable or provides the treating physician with information that changes patient management is considered not medically necessary.

Use of added stains when the diagnosis is already known based on morphologic evaluation of the primary stain is considered not medically necessary.

Special stains and IHC stains may be used selectively with appropriate documentation regarding medical necessity.

POLICY EXCEPTIONS

None

POLICY GUIDELINES

The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member's specific benefit plan language.

Medically Necessary is defined as those services, treatments, procedures, equipment, drugs, devices, items or supplies furnished by a covered Provider that are required to identify or treat a Member's illness, injury or Mental Health Disorders, and which the Company determines are covered under this Benefit Plan based on the criteria as follows in A through D:

A.  consistent with the symptoms or diagnosis and treatment of the Member's condition, illness, or injury; and

B.  appropriate with regard to standards of good medical practice; and

C.  not solely for the convenience of the Member, his or her Provider; and

D. the most appropriate supply or level of care which can safely be provided to Member. When applied to the care of an Inpatient, it further means that services for the Member's medical symptoms or conditions require that the services cannot be safely provided to the Member as an Outpatient.

For the definition of medical necessity, “standards of good medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. BCBSMS makes no payment for services, treatments, procedures, equipment, drugs, devices, items or supplies which are not documented to be Medically Necessary. The fact that a Physician or other Provider has prescribed, ordered, recommended, or approved a service or supply does not in itself, make it Medically Necessary.

Investigative is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized as a generally accepted standard of good medical practice for the treatment of the condition being treated and; therefore, is not considered medically necessary. For the definition of Investigative, “generally accepted standards of medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. In order for equipment, devices, drugs or supplies [i.e, technologies], to be considered not investigative, the technology must have final approval from the appropriate governmental bodies, and scientific evidence must permit conclusions concerning the effect of the technology on health outcomes, and the technology must improve the net health outcome, and the technology must be as beneficial as any established alternative and the improvement must be attainable outside the testing/investigational setting.

POLICY HISTORY

06/15/2017: New policy added. Effective 07/15/2017.

09/30/2022: Policy Guidelines updated to change "Nervous/Mental Conditions" to "Mental Health Disorders" and "Medically Necessary" to "medical necessity." Code Reference section updated to revise description for ICD-10 diagnosis code C84.43, effective 10/01/2022.

01/24/2023: Policy reviewed; no changes.

09/27/2023: Code Reference section updated to make note of deleted ICD-10 diagnosis code.

03/15/2024: Policy reviewed; no changes.

10/01/2024: Code Reference section updated to add new ICD-10 diagnosis codes C86.00, C86.01, C86.10, C86.20, C86.21, C86.30, C86.31, C86.40, C86.41, C86.50, C86.51, C86.60, C88.00, C88.20, C88.30, C88.40, and C88.90. Removed deleted ICD-10 diagnosis code D48.1.

03/26/2025: Policy reviewed; no changes.

SOURCE(S)

1. Batts K, et al. Appropriate use of special stains for identifying Helicobacter pylori: recommendations from the Rodger C. Haggitt Gastrointestinal Pathology Society. Am J Surg Pathol 2013;37(1 l):el2-22.

2. Chitkara Y. Upfront special staining for Helicobacter pylori in gastric biopsy specimens is not indicated. AJCP 2015; 143:84-8.

3. Goldblum JR: Current issues in Barrett's esophagus and Barrett's-related dysplasia. Modem Pathology (2015) 28, S1-S6.

4. Hartman DJ, et al. Are routine ancillary stains required to diagnose Helicobacter infection in gastric biopsy specimens? Am J Clin Path 2012;137:255-60.

5. Smith SB, et al. Helicobacter pylori. To stain or not to stain? Am J Clin Path 2012;137:733-8.

6. Wright CL, et al. The use of routine special stains for upper gastrointestinal biopsies. Am J Surg Pathol 2006;30:357-61.

7. Yantiss RK: Diagnostic challenges in the pathologic evaluation of Barrett's esophagus. Arch Pathol Lab Med 2010; 134: 1589-1600.

CODE REFERENCE

This may not be a comprehensive list of procedure codes applicable to this policy.

The code(s) listed below are ONLY medically necessary if the procedure is performed according to the "Policy" section of this document.

Medically Necessary Codes

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