Aetna modified CPB 0747 for transanal endoscopic microsurgery (TEM), effective November 27, 2025. Here's what billing teams need to do.
Aetna, a CVS Health company, updated its TEM coverage policy under CPB 0747, clarifying which rectal conditions qualify as medically necessary and expanding the list of non-covered indications. The single CPT code in play is 0184T — excision of a rectal tumor via transanal endoscopic microsurgical approach. If your practice or facility bills 0184T for Aetna members, this policy revision defines exactly where coverage starts and stops.
Quick-Reference Table
| Field | Detail |
|---|---|
| Payer | Aetna, a CVS Health company |
| Policy | Transanal Endoscopic Microsurgery – CPB 0747 |
| Policy Code | CPB 0747 |
| Change Type | Modified |
| Effective Date | November 27, 2025 |
| Impact Level | Medium — narrow covered indications with a long experimental list |
| Specialties Affected | Colorectal surgery, general surgery, gastroenterology |
| Key Action | Audit any 0184T claims billed with non-covered diagnoses before or after November 27, 2025 |
Aetna Transanal Endoscopic Microsurgery Coverage Criteria and Medical Necessity Requirements 2025
Aetna's TEM coverage policy is tight. Only three indications clear the medical necessity bar under CPB 0747 in the CPB 0747 Aetna system.
Medically necessary indications for CPT 0184T:
| # | Covered Indication |
|---|---|
| 1 | Benign rectal tumors (adenomas) |
| 2 | Low-risk Tis and T1 rectal carcinoma — ICD-10 codes D01.1 and D01.2 (carcinoma in situ) and C20 for low-risk malignant neoplasm of the rectum apply here |
| 3 | Small rectal carcinoids less than 2 cm in diameter — coded with D3A.026 (benign carcinoid tumor of the rectum) or C7a.026 for malignant carcinoid |
That's it. Three buckets. Everything else falls into the experimental and investigational category.
The Aetna transanal endoscopic microsurgery coverage policy does not specify prior authorization requirements in the CPB itself. That said, 0184T is a surgical procedure code, and most Aetna commercial plans require prior authorization for surgical procedures. Check the specific plan benefits before scheduling. Don't assume the absence of a PA requirement in the clinical policy means the plan doesn't require one at the claim level.
Reimbursement for 0184T is contingent on meeting these selection criteria. If the diagnosis doesn't match one of the three covered indications, Aetna won't cover it — and you'll face a claim denial.
Aetna TEM Exclusions and Non-Covered Indications
This is where CPB 0747 does the most work — and where your billing team faces the most risk.
Aetna explicitly labels 18 conditions as experimental, investigational, or unproven for TEM. "Effectiveness has not been established" is the stated reason for all of them. That phrase matters in an appeal — it tells you exactly what clinical evidence Aetna will expect to see if you push back.
The non-covered list includes some diagnoses that might seem like reasonable TEM candidates to a surgeon. Giant villous adenoma of the rectum (D12.7–D12.9) is on the experimental list, even though standard benign adenomas are covered. Rectal neuroendocrine tumors in advanced stages or with metastasis are excluded — but early-stage benign carcinoids under 2 cm are covered. The line matters.
Here are all 18 non-covered indications as stated in CPB 0747:
| # | Excluded Procedure |
|---|---|
| 1 | Advanced rectal cancer |
| 2 | Anorectal melanoma (C43.51) |
| 3 | Benign rectal strictures |
| 4 | Colorectal anastomotic stenosis (K56.690–K56.699) |
| 5 | Colovesical fistula |
| 6 | Functional constipation |
| 7 | Giant villous adenoma of rectum (D12.7–D12.9) |
| 8 | Megacolon (B57.32) |
| 9 | Rectal amyloidoma |
| 10 | Rectal gastrointestinal stromal tumor (C49.A0–C49.A9) |
| 11 | Rectal neuroendocrine tumor in advanced stages or with metastasis |
| 12 | Rectal prolapse and diverticula (K57.x series) |
| 13 | Rectal schwannoma (D36.15) |
| 14 | Rectal ulcer syndrome |
| 15 | Recto-urinary fistula, including recto-urethral fistula |
| 16 | Recto-vesical fistula |
| 17 | Retro-rectal (pre-sacral) tumors |
| 18 | Tubulovillous adenoma of the colon |
The giant villous adenoma distinction deserves attention. A giant villous adenoma of the rectum codes to D12.7–D12.9 — the same code range used for other benign rectal neoplasms. If your documentation says "benign adenoma" generically, the diagnosis code may look covered. But if the operative or pathology report clarifies "giant villous adenoma," Aetna considers TEM unproven for that specific subtype. Make sure your ICD-10 code matches the actual diagnosis — not the most favorable one.
Coverage Indications at a Glance
| Indication | Coverage Status | Key ICD-10 Codes | Notes |
|---|---|---|---|
| Benign rectal adenomas | Covered | D12.7, D12.8, D12.9 | Excludes giant villous adenoma |
| Low-risk Tis rectal carcinoma | Covered | D01.1, D01.2 | Carcinoma in situ only |
| Low-risk T1 rectal carcinoma | Covered | C20 (low-risk) | Not applicable to advanced rectal cancer |
| Small rectal carcinoids < 2 cm | Covered | D3A.026, C7a.026 | Size threshold is hard — document diameter |
| Advanced rectal cancer | Not Covered | C20 (advanced) | Experimental per CPB 0747 |
| Anorectal melanoma | Not Covered | C43.51 | Experimental |
| Benign rectal strictures | Not Covered | — | Experimental |
| Colorectal anastomotic stenosis | Not Covered | K56.690–K56.699 | Experimental |
| Colovesical fistula | Not Covered | — | Experimental |
| Functional constipation | Not Covered | — | Experimental |
| Giant villous adenoma of rectum | Not Covered | D12.7, D12.8, D12.9 | Experimental — same codes as covered benign adenoma; documentation critical |
| Megacolon | Not Covered | B57.32 | Experimental |
| Rectal amyloidoma | Not Covered | — | Experimental |
| Rectal GIST | Not Covered | C49.A0–C49.A9 | Experimental |
| Rectal neuroendocrine tumor (advanced/metastatic) | Not Covered | C7a.026 (advanced) | Early-stage < 2 cm may qualify |
| Rectal prolapse and diverticula | Not Covered | K57.x | Experimental |
| Rectal schwannoma | Not Covered | D36.15 | Experimental |
| Rectal ulcer syndrome | Not Covered | — | Experimental |
| Recto-urinary fistula / recto-urethral fistula | Not Covered | — | Experimental |
| Recto-vesical fistula | Not Covered | — | Experimental |
| Retro-rectal (pre-sacral) tumors | Not Covered | — | Experimental |
| Tubulovillous adenoma of the colon | Not Covered | — | Experimental |
Aetna TEM Billing Guidelines and Action Items 2025
The effective date is November 27, 2025. These action items apply now.
| # | Action Item |
|---|---|
| 1 | Pull all 0184T claims from the past 12 months and check the diagnosis codes. If any claims used ICD-10 codes from the non-covered list — especially D12.7–D12.9 for giant villous adenoma or K57.x for diverticular disease — review those claims for potential exposure. Recoupment risk is real if diagnoses don't align with the covered indications. |
| 2 | Update your charge capture for CPT 0184T to flag non-covered ICD-10 codes before claims go out. Build a hard stop or soft alert in your practice management system. The list of non-covered diagnoses is long — 18 conditions — and some of them share codes with covered conditions (the D12.x range is the best example). |
| 3 | Document tumor size in the operative and pre-op records for all carcinoid cases. The "less than 2 cm" threshold for rectal carcinoids is a hard clinical criterion. Aetna will look for size in the record if they audit or review a 0184T claim. A note that says "rectal carcinoid" without dimensions doesn't support the coverage criterion. |
| 4 | Verify prior authorization requirements at the plan level, not just the CPB. CPB 0747 doesn't list a PA requirement, but that doesn't mean the individual commercial plan omits one. Call or check the plan benefits for any scheduled TEM procedure on an Aetna member before the case goes to the OR. |
| 5 | Train your coding team on the giant villous adenoma distinction. This is the trickiest part of these billing guidelines. D12.7, D12.8, and D12.9 cover benign neoplasms of the rectum broadly — and benign adenomas are covered for TEM. But if the pathology or operative note says "giant villous adenoma," that specific subtype is experimental. Your coders need to read past the generic code description and check the documentation. |
| 6 | If a case involves an off-label or borderline indication, loop in your compliance officer before billing. Some of these non-covered categories — recto-urinary fistula, retro-rectal tumors, rectal schwannoma — are uncommon. But if a surgeon performs TEM for one of them, billing 0184T without a covered diagnosis is a denial waiting to happen. Get your compliance officer's read before the claim goes out. |
| Previous Version | Current Version |
|---|---|
| Coverage is considered experimental and investigational for all indications | Coverage is considered medically necessary when specific criteria are met |
| Prior authorization is not required | Prior authorization is required for initial treatment |
| Documentation must include clinical history | Documentation must include clinical history |
| Re-review every 24 months | Re-review every 12 months with updated clinical documentation |
CPT, HCPCS, and ICD-10 Codes for Transanal Endoscopic Microsurgery Under CPB 0747
Covered CPT Codes (When Selection Criteria Are Met)
| Code | Type | Description |
|---|---|---|
| 0184T | CPT | Excision of rectal tumor, transanal endoscopic microsurgical approach (i.e., TEMS), including muscular |
Key ICD-10-CM Diagnosis Codes
These codes appear in CPB 0747. Coverage status depends on the specific indication, not just the code — review the table above before billing.
| Code | Description |
|---|---|
| B57.32 | Megacolon in Chagas' disease |
| C20 | Malignant neoplasm of rectum [low-risk covered; advanced not covered] |
| C43.51 | Malignant melanoma of anal skin |
| C49.A0–C49.A9 | Gastrointestinal stromal tumor (rectal GIST) |
| C7a.026 | Malignant carcinoid tumor of the rectum |
| D01.1 | Carcinoma in situ of rectosigmoid junction and rectum |
| D01.2 | Carcinoma in situ of rectosigmoid junction and rectum |
| D12.0 | Benign neoplasm of colon |
| D12.1 | Benign neoplasm of colon |
| D12.2 | Benign neoplasm of colon |
| D12.3 | Benign neoplasm of colon |
| D12.4 | Benign neoplasm of colon |
| D12.5 | Benign neoplasm of colon |
| D12.6 | Benign neoplasm of colon |
| D12.7 | Benign neoplasm of rectosigmoid junction, rectum, anus, and anal canal [includes giant villous adenoma — see coverage status] |
| D12.8 | Benign neoplasm of rectosigmoid junction, rectum, anus, and anal canal [includes giant villous adenoma — see coverage status] |
| D12.9 | Benign neoplasm of rectosigmoid junction, rectum, anus, and anal canal [includes giant villous adenoma — see coverage status] |
| D36.15 | Benign neoplasm of peripheral nerves and autonomic nervous system of abdomen (rectal schwannoma) |
| D3A.026 | Benign carcinoid tumor of the rectum |
| K56.690–K56.699 | Other intestinal obstruction (colorectal anastomotic stenosis) |
| K57.0–K57.5x | Diverticular disease of intestine |
The full ICD-10 list in CPB 0747 includes 158 codes. The table above covers the clinically significant codes most relevant to TEM billing decisions. Review the full policy at app.payerpolicy.org/p/aetna/0747 for the complete code set.
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