malignant salivary gland tumour staging

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Major salivary gland cancer staging refers to TNM staging of malignant tumors of the major salivary glands (parotid, submandibular, and sublingual glands). In contrast, tumors arising from minor salivary glands are staged according to their site of origin. The following article reflects the 8th edition published by the American Joint Committee on Cancer, which is used for staging starting January 1, 2018 .

Primary tumor (T)

TX: primary tumor cannot be assessed
T0: no evidence of primary tumor
Tis: carcinoma in situ
T1: tumor ≤2 cm in greatest dimension without extraparenchymal extension*
T2: tumor >2 cm and ≤4 cm without extraparenchymal extension*
T3:
- tumor >4 cm and/or
- tumor with extraparenchymal extension*
T4: moderately or very advanced
- T4a: moderately advanced local disease:
  - tumor invades skin, mandible, ear canal, and/or facial nerve
- T4b: very advanced local disease:
  - tumor invades base of skull and/or pterygoid plates, or
  - tumor encases the carotid artery

*Extraparenchymal extension refers to clinical or macroscopic pathologic evidence of soft tissue invasion. Microscopic evidence does not suffice.

Regional lymph node (N)

Regional nodal status is defined the same as for most other cancers of the head and neck. See the main article, cervical lymph node (staging).

Distant metastases (M)

The terms pM0 and MX are not valid TNM categories. The following categories may be used, either in the clinical classification (c) for patients with cancer identified before treatment and/or in the pathological classification (p) for patients for whom surgery is the first definitive therapy:

cM0: no evidence of metastases
cM1: distant metastasis
pM1: distant metastasis, microscopically confirmed

Stage groups

The prognostic stage groups are defined the same as for most other cancers of the head and neck:

Stage 0
- Tis, N0, M0
Stage I
- T1, N0, M0
Stage II
- T2, N0, M0
Stage III
- T3, N0, M0
- [T0, T1, T2, T3], N1, M0
Stage IVA
- T4a, [N0, N1], M0
- [T0, T1, T2, T3, T4a], N2, M0
Stage IVB
- [Any T], N3, M0
- T4b, [Any N], M0
Stage IVC
- [Any T], [Any N], M1

Changes since prior versions

Compared to the prior edition, there has been no change in primary tumor category definitions, but regional lymph node categories have been updated as it has elsewhere in the head and neck to emphasize extranodal extension.