Reference only. Testing guidance shown is derived from published clinical guidelines and regulatory sources. It does not constitute a clinical recommendation for any individual patient. Payer coverage information is a general summary and may not reflect current policy or individual benefit design. Full disclaimer
Colorectal CancerICD-10: C20
Rectal Adenocarcinoma
Adenocarcinoma arising in the rectum. Shares biomarker testing priorities with colon cancer; HER2 testing increasingly recommended given emerging antibody-drug conjugate therapies.
AJCC TNM Staging
8th Edition (2017)American Joint Committee on Cancer TNM staging — the primary staging system for solid tumors. Version 8 is current for most solid tumor types.
Stage ITumor ≤4 cm, no nodal or distant metastasis (T1-T2a, N0, M0). Surgically resectable.Stage IIATumor >4–5 cm, no nodal or distant metastasis (T2b, N0, M0). Resectable.Stage IIBTumor with ipsilateral hilar/peribronchial nodal involvement, or tumor >5–7 cm (T1-2/N1 or T3/N0, M0). Potentially resectable.Stage IIIAIpsilateral mediastinal or subcarinal nodal involvement, or T3-4/N1-2/M0. Potentially resectable in select cases; often requires multidisciplinary evaluation.Stage IIIB–IIICContralateral mediastinal/supraclavicular nodes, or very locally advanced disease (T3-4/N2-3/M0). Typically unresectable; treated with concurrent chemoradiation ± durvalumab.Stage IVASingle extrathoracic metastatic lesion or contralateral lung nodule or pleural/pericardial involvement. Metastatic but potentially oligometastatic.Stage IVBMultiple extrathoracic metastases in one or more organs. Widely metastatic disease.
Recommendations reflect published guidelines as of their listed evidence dates. Staging categories without recommendations may not yet be included in this reference. Always consult current guidelines and institutional protocols.