From the Guidelines
The staging for sinonasal cancer primarily follows the American Joint Committee on Cancer (AJCC) TNM classification system, which evaluates the primary tumor extent (T), regional lymph node involvement (N), and presence of distant metastasis (M) 1.
Staging Components
The TNM staging system is crucial for determining the prognosis and guiding treatment planning for sinonasal cancer. The components of the TNM system are:
- T staging: ranges from T1 to T4, with T1 representing a tumor confined to one subsite with no bone erosion, while T4 tumors invade critical structures like the brain, orbit, or cranial nerves.
- N staging: assesses lymph node involvement, from N0 (no regional lymph node metastasis) to N3 (metastasis in lymph nodes larger than 6 cm).
- M staging: simply M0 (no distant metastasis) or M1 (distant metastasis present).
Importance of Accurate Staging
Accurate staging is essential for treatment planning, as early-stage cancers may be treated with surgery or radiation alone, while advanced stages typically require multimodal therapy including surgery, radiation, and possibly chemotherapy 1. Imaging studies like CT, MRI, and PET scans are essential for proper staging assessment, along with thorough physical examination and tissue biopsy.
Key Considerations
- Sinonasal cancer staging is based on the latest eighth edition of the American Joint Committee on Cancer classification of cancer 1.
- The approach to staging and posttreatment imaging varies and depends on the anatomic site and pathology.
- Timely detection and accurate delineation of the extent of recurrent disease can help guide salvage therapy and improve prognosis.
From the Research
Staging of Sinonasal Cancer
The staging of sinonasal cancer is based on the American Joint Committee on Cancer (AJCC) TNM staging system, which takes into account the size and extent of the primary tumor (T), the presence of lymph node metastasis (N), and the presence of distant metastasis (M) 2.
TNM Staging System
- The T category is used to describe the size and extent of the primary tumor, with higher numbers indicating more advanced disease.
- The N category is used to describe the presence and extent of lymph node metastasis, with higher numbers indicating more advanced disease.
- The M category is used to describe the presence of distant metastasis, with M0 indicating no distant metastasis and M1 indicating distant metastasis.
Clinical Staging
Clinical staging is used to describe the extent of disease based on clinical evaluation, including physical examination, imaging studies, and laboratory tests. For example, a study of 140 cases of maxillary sinus squamous cell carcinoma found that the clinical staging was as follows:
- cStage I: 5 cases
- cStage II: 9 cases
- cStage III: 36 cases
- cStage IVa: 74 cases
- cStage IVb: 16 cases 3.
Importance of Staging
Accurate staging is important for determining the prognosis and guiding treatment decisions for patients with sinonasal cancer. Different staging systems have been proposed for specific histopathologic subtypes, and further research is needed to refine and improve these systems 2.
Treatment Decisions
Treatment decisions for sinonasal cancer are based on the stage and extent of disease, as well as the patient's overall health and preferences. A multidisciplinary approach, including surgery, radiation therapy, and chemotherapy, is often used to treat sinonasal cancer 3, 4, 5.