The Short Answer
Prior authorization (PA) — sometimes called pre-authorization, pre-certification, or pre-approval — is a process by which a health insurance payer requires a provider to obtain approval before a service, drug, or diagnostic test is delivered. Without that approval, the payer can legitimately deny the claim, leaving the patient or the lab holding the bill.
For genetic laboratories and oncology revenue cycle teams, PA is not a peripheral concern. It sits at the center of your reimbursement model. Molecular diagnostics, hereditary cancer panels, tumor biomarker assays, and specialty oncology drugs are among the most heavily managed categories in every payer's utilization management program.
Why Payers Use Prior Authorization
Payers implement PA programs for two stated reasons: clinical appropriateness and cost management. The clinical argument is that some services are only appropriate in specific clinical contexts — a BRCA1/2 test ordered without documented family history or clinical criteria, for example, may not meet coverage requirements. The cost argument is straightforward: high-cost genetic tests and oncology therapies represent significant per-unit spend, and payers use PA as a gate.
In practice, utilization management programs vary enormously. Commercial payers may require PA for nearly every molecular test over a certain CPT code range. Medicare typically follows Local Coverage Determinations (LCDs) or National Coverage Determinations (NCDs), with specific coverage requirements and documentation standards. Medicaid requirements differ by state.
Understanding why a payer uses PA for a given service helps you build better submissions from the start.
The Policy Landscape You're Navigating
Before you can submit a successful prior authorization, you need to understand which policies govern coverage for the test or treatment in question.
Local Coverage Determinations (LCDs) are coverage rules issued by Medicare Administrative Contractors (MACs) — the regional contractors that process Medicare claims. An LCD specifies which diagnoses and clinical circumstances support coverage for a given service, and which do not. For molecular diagnostics, LCDs issued by Palmetto GBA (which administers the MolDX program) are particularly important.
National Coverage Determinations (NCDs) are coverage rules set at the federal level by the Centers for Medicare & Medicaid Services (CMS). NCDs supersede LCDs in their coverage scope. NCDs relevant to oncology include policies on next-generation sequencing (NGS) panels and certain companion diagnostics.
MolDX is Palmetto GBA's molecular diagnostic testing program. MolDX establishes technical assessment and coverage requirements for molecular tests billed to Medicare. Labs billing tests managed under MolDX must complete a technical assessment and obtain a DEX Z-code for billing. Many commercial payers reference MolDX criteria in their own policies.
NCCN Clinical Practice Guidelines are not payer policies, but they carry significant weight in the PA process. The National Comprehensive Cancer Network publishes evidence-based guidelines for oncology, and payers frequently cite NCCN category designations (Category 1, 2A, 2B, 3) when determining whether a drug or test is medically necessary. Category 1 designations (based on high-level evidence with uniform NCCN consensus) are the most likely to be covered without dispute.
Medical policies are insurer-specific documents that define coverage criteria for services beyond what LCDs and NCDs specify. Every major commercial payer publishes medical policies, and these can differ substantially from one payer to the next — even for the same test or drug.
The Prior Authorization Workflow
A standard PA workflow for genetic testing or oncology involves the following steps:
- Service identification: The ordering clinician determines which test or treatment is needed and whether it requires PA under the patient's plan.
- Policy lookup: The lab or provider's RCM team identifies the applicable coverage policy — LCD, NCD, medical policy, or formulary — and confirms the specific clinical criteria required.
- Documentation assembly: The team gathers supporting clinical documentation: diagnosis codes (ICD-10), procedure codes (CPT/HCPCS), treating physician notes, prior treatment history (relevant to step therapy requirements), and any supporting clinical literature or guideline references.
- Submission: The PA request is submitted through the payer's portal, fax, or EDI channel — depending on what that payer supports.
- Payer review: The payer's medical director or designated reviewer evaluates the request against their policy criteria. Turnaround times vary; federally mandated timeframes exist for certain plan types and urgency levels.
- Decision: The payer issues an approval (with or without conditions), a denial, or a request for additional information (a "pend" or "hold").
- Appeals (if denied): If the initial request is denied, the provider has the right to appeal through defined escalation pathways.
Common Terms to Know
- Medical necessity: The clinical justification that a service is appropriate, reasonable, and necessary for the diagnosis or treatment of a covered condition. Most PA denials cite failure to establish medical necessity.
- CPT codes: Current Procedural Terminology codes that identify the specific procedure or test being requested.
- ICD-10 codes: International Classification of Diseases codes that document the patient's diagnosis and clinical context.
- HCPCS codes: Healthcare Common Procedure Coding System codes used primarily for Medicare and Medicaid billing, including J-codes for injectable drugs.
- Formulary: A payer's list of covered drugs; specialty oncology drugs are often tiered or require PA regardless of tier.
- Peer-to-peer review: A direct conversation between the ordering physician and the payer's medical director, often the most effective tool when an initial request is denied.
What Makes Genetic Testing and Oncology Different
Standard PA workflows are built for high-volume, relatively simple services. Genetic testing and oncology are neither.
Molecular diagnostic tests involve complex coding requirements (including DEX Z-codes for MolDX), evolving coverage policies that frequently lag behind the science, and clinical context that is difficult to capture in a standard form. Oncology drugs often require demonstration of biomarker expression (PD-L1, HER2, EGFR, MSI/MMR status), specific line-of-therapy sequencing, or companion diagnostic results — all of which must be documented precisely.
A submission that would be straightforward for a standard service becomes a clinical narrative exercise for a next-generation sequencing panel or a checkpoint inhibitor. That is the gap Converus is built to close.