Does C4A.21 require prior authorization?

No, C4A.21 does not require prior authorization (high confidence). Covered without prior authorization.

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`C4A.21`, Merkel cell carcinoma of right ear and external auricular canal

ICD-10-CM

Prior Authorization

No Prior Auth Required

Covered without prior authorization (high confidence)

Documentation Required

Operative notes and pathology documentation must clearly show that Mohs was performed using accepted technique and that the surgeon acted in both surgical and pathology capacities.
Medical record must document location, number, and size of lesion(s); number of stages performed; and number of specimens per stage.
Histology documentation must include for the first stage: presence of tumor, depth of invasion, pathological pattern, cell morphology, and perineural invasion if present; subsequent stages must note if characteristics are same or describe differences.
Documentation must explain why the lesion will not be or was not managed by standard excision or destruction, and when applicable justify the selection of complex repair techniques (adjacent tissue transfer, flap, graft) or referral to plastic surgery.

Key Coverage Criteria

Mohs micrographic surgery is covered when selected because the lesion's complexity (e.g., poorly defined borders, suspected deep invasion, recurrent lesion, prior radiation), size, or anatomic location requires maximal tissue conservation and other approaches (standard excision or destruction) are not medically reasonable or necessary.
Mohs surgery is considered covered when the surgeon performs both the surgical excision and the pathologic examination (surgeon acting in integrated surgical and pathology roles) as part of the Mohs technique.
Initial MRD testing is covered for patients with cancer when baseline tumor profiling from a prior analysis is utilized, using listed bespoke/plasma-series MRD tests (e.g., Signatera Bespoke Assay Design + Plasma Series Bundle, RaDaR Bespoke Assay Design + Plasma Series Bundle, Oncodetect Bespoke Assay Design + Plasma Test Bundle, Guardant Reveal MRD Bundle, Guardant360 Response).
Subsequent MRD testing for patients with cancer is covered only if there is clinical evidence of an a priori change in tumor genetic content in accordance with NCD 90.2.
Initial MRD testing is covered for patients without current cancer (per policy definition) when baseline tumor profiling from a prior analysis is utilized, using listed recurrence-monitoring bespoke + single-plasma tests (e.g., Signatera Recurrence Monitoring Bespoke Assay Design + single Plasma Test, RaDaR Recurrence Monitoring, Oncodetect Bespoke Assay, Pathlight Recurrence Monitoring).
Subsequent MRD testing for patients without cancer is covered as specified for listed single-plasma recurrence-monitoring tests (e.g., Signatera Recurrence Monitoring single Plasma Test, RaDaR Recurrence Monitoring single Plasma Test, Oncodetect single Plasma Test, Pathlight Recurrence Monitoring single Plasma Test).

20 Active Policies

CGS-J15-L38067, MolDX: Next-Generation Sequencing for Solid Tumors

J15

CGS-J15-L38065, MolDX: Plasma-Based Genomic Profiling in Solid Tumors

J15

CGS-J15-L34195, Mohs Micrographic Surgery

J15

CGS-J15-L38822, MolDX: Minimal Residual Disease Testing for Cancer

J15

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C4A.21, Merkel cell carcinoma of right ear and external auricular canal