CPT Code Overview

CPT 81405 is used to report genetic and molecular pathology testing for the full gene sequence or targeted sequence analysis of more than five exons of the TP53 (tumor protein 53) gene. This testing is clinically relevant for conditions such as Li-Fraumeni syndrome and various tumor samples, providing critical information for diagnosis and management of hereditary cancer syndromes and certain hematologic malignancies. The service is typically performed in a laboratory setting (POS 81) or within a hospital (POS 19), depending on the clinical context. As a molecular pathology procedure, it plays a key role in precision medicine and cancer risk assessment.

Clinical Context

A patient presents with a suspected or confirmed hematologic malignancy, such as acute myelogenous leukemia or myelodysplastic syndrome. The treating physician, often a hematologist or oncologist, orders genetic testing to assess for mutations in the TP53 gene, which may influence prognosis and treatment decisions. The laboratory receives a tumor or blood sample and performs full gene sequencing or targeted analysis of more than 5 exons of TP53, as described by CPT code 81405. Results are interpreted by a pathologist or clinical laboratory specialist and reported back to the ordering provider for integration into the patient's care plan.

Coding Specifications

• Modifier 26: Used to indicate the professional component of the laboratory service, typically when the interpretation is performed separately from the technical component.

• Modifier 91: Used when the laboratory test is repeated on the same patient for clinical reasons, such as monitoring disease progression or response to therapy.

Associated Provider Taxonomies:

• 207ZP0102X: Pathology - Clinical Pathology/Laboratory Medicine
• 207Q00000X: Family Medicine Physician
• 207R00000X: Internal Medicine Physician

These taxonomies represent providers who may order or interpret TP53 genetic testing, including pathologists, family medicine physicians, and internal medicine physicians.

Related Diagnoses

• C92.00: Acute myelogenous leukemia not having achieved remission

  • Relevant for TP53 testing to assess genetic mutations in newly diagnosed AML.

• C92.02: Acute myelogenous leukemia in remission

  • Used for monitoring TP53 status in patients with AML in remission.

• C92.30: Chronic myeloid leukemia not having achieved remission

  • TP53 testing may inform prognosis or treatment in CML.

• C92.32: Chronic myeloid leukemia in remission

  • Used for ongoing assessment in CML patients.

• C92.40: Acute leukemia of unspecified cell type not having achieved remission

  • TP53 analysis may help clarify genetic risk in unspecified acute leukemia.

• C92.42: Acute leukemia of unspecified cell type in remission

  • Used for follow-up genetic testing in remission.

• C92.50: Myeloproliferative disease, unspecified, not having achieved remission

  • TP53 testing may be indicated for diagnostic clarification.

• C92.52: Myeloproliferative disease, unspecified, in remission

  • Used for monitoring genetic status.

• C92.60: Myelodysplastic disease, not having achieved remission

  • TP53 mutations are relevant in MDS for prognosis and therapy.

• C92.62: Myelodysplastic disease in remission

  • Used for follow-up testing in MDS.

• C92.A0: Juvenile myelomonocytic leukemia not having achieved remission

  • TP53 testing may be part of genetic workup in JMML.

• C92.A2: Juvenile myelomonocytic leukemia in remission

  • Used for monitoring genetic changes.

• C92.Z0: Other myeloid leukemia not having achieved remission

  • TP53 analysis may be indicated for other myeloid leukemias.

• C92.Z2: Other myeloid leukemia in remission

  • Used for ongoing genetic assessment.

• C94.00: Acute leukemia of unspecified cell type, site unspecified

  • TP53 testing may help define genetic risk.

• C94.02: Acute leukemia of unspecified cell type, bone marrow

  • Used for bone marrow samples in acute leukemia.

• C94.6: Myeloid sarcoma

  • TP53 mutations may be relevant in myeloid sarcoma.

• D46.0: Refractory anemia

  • TP53 testing may be indicated in refractory anemia for diagnostic purposes.

• D46.1: Refractory anemia with ring sideroblasts

  • Used for genetic assessment in this subtype.

• D46.20: Refractory anemia with excess of blasts, unspecified

  • TP53 analysis may inform prognosis.

• D46.21: Refractory anemia with excess of blasts, subtype 1

  • Used for genetic testing in this subtype.

• D46.22: Refractory anemia with excess of blasts, subtype 2

  • TP53 testing may be relevant for subtype 2.

• D46.A: Refractory cytopenia with multilineage dysplasia

  • Used for genetic assessment in multilineage dysplasia.

• D46.B: Refractory anemia with excess blasts in transformation

  • TP53 mutations may be relevant in transformation phase.

• D46.C: Myelodysplastic syndrome with isolated del(5q)

  • Used for genetic testing in MDS with del(5q).

• D46.4: Chronic myelomonocytic leukemia

  • TP53 testing may be indicated in CMML.

• D46.Z: Other myelodysplastic syndromes

  • Used for genetic assessment in other MDS types.

• D46.9: Myelodysplastic syndrome, unspecified

  • TP53 analysis may clarify genetic risk in unspecified MDS.

Related CPT Codes

• 81404: TP53 (tumor protein 53), targeted sequence analysis of 2‑5 exons

  • Used for more limited TP53 analysis, typically when fewer exons are tested. May be used as an alternative to 81405 when clinical indications require less extensive sequencing.

• 81351: Tier 1 TP53 testing code that replaced 81405 in certain groupings

  • Represents a newer, tiered coding structure for TP53 testing. May be used instead of 81405 depending on payer requirements and laboratory coding practices.

These codes are related to 81405 in that they all describe TP53 genetic testing, but differ in the extent of sequencing or coding structure. 81404 and 81351 may be used as alternatives or in place of 81405 depending on clinical and billing circumstances.