Esophageal and esophagogastric junction adenocarcinoma (staging)

Esophageal and esophagogastric junction adenocarcinoma staging refers to TNM staging of adenocarcinoma originating in the esophagus or esophagogastric junction (including tumors whose center is within the proximal 2 cm of the gastric cardia).

Related histologies included in this system are high-grade glandular dysplasia (intraepithelial neoplasia), adenoid cystic carcinoma, mucoepidermoid carcinoma, mixed adenoneuroendocrine carcinoma, and undifferentiated carcinoma with glandular component but without squamous component. While the individual TNM category definitions are identical to that of other histologies of esophagus and esophagogastric junction cancers, the prognostic stage groups are different. The following article reflects the 8^th edition published by the American Joint Committee on Cancer, which is used for staging starting 1 January 2018 ^1,2.

For the other histological types, please refer to their dedicated staging articles:  

• esophageal and esophagogastric junction squamous cell carcinoma (staging)
• esophageal and esophagogastric junction neuroendocrine tumor (staging)

Primary tumor (T)

• Tx: primary tumor cannot be assessed
• T0: no evidence of primary tumor
• Tis: high-grade dysplasia (malignant cells confined to the epithelium by the basement membrane)
• T1: tumor invades lamina propria, muscularis mucosae or submucosa
  • T1a: invades lamina propria or muscularis mucosae
  • T1b: invades submucosa
• T2: tumor invades muscularis propria
• T3: tumor invades adventitia
• T4: tumor invades adjacent structures
  • T4a: tumor invades pleura, pericardium, azygos vein, diaphragm, or peritoneum
  • T4b: tumor invades other adjacent structures, e.g. aorta, vertebra, or trachea

Regional lymph node (N)

• Nx: regional nodes cannot be assessed
• N0: no regional lymph node metastasis
• N1: metastasis in 1-2 regional nodes
• N2: metastasis in 3-6 regional nodes
• N3: metastasis in ≥7 regional nodes

The regional lymph node stations are defined separately: esophageal lymph node stations.

​Distant metastasis (M)

• cM0: no distant metastasis
• cM1: distant metastasis clinically present
• pM1: distant metastasis pathologically (microscopically) confirmed

NB: The MX category is no longer used, it was removed in the 6th edition of the TNM system, if the presence of metastases is not known the cancer is assigned M0 ⁵.

Other prognostic factors

The prognostic stage group also depends on the histologic grade.

Histologic grade (G)

• Gx: differentiation cannot be assessed
• G1: well-differentiated. >95% of the tumor is composed of well-formed glands
• G2: moderately differentiated. 50% to 95% of the tumor showing gland formation
• G3: poorly differentiated or undifferentiated; composed of nest and sheets of cells with <50% of tumor demonstrating glandular formation

Stage groups

Staging criteria are separated by treatment strategy: clinical (cTNM) classification prior to any treatment, pathologic (pTNM) classification after surgery alone, and posttherapy pathologic (ypTNM) classification after both neoadjuvant (systemic or radiation therapy) treatment and then surgery.

Clinical (cTNM)

• stage 0
  • ​Tis, N0, M0
• stage I
  • T1, N0, M0
• stage IIA
  • T1, N1, M0
• stage IIB
  • ​T2, N0, M0
• stage III
  • ​T2, N1, M0
  • T3, [N0, N1], M0
  • T4a, [N0, N1], M0
• stage IVA
  • [T1, T2, T3, T4a], N2, M0
  • T4b, [N0, N1, N2], M0
  • [Any T], N3, M0
• stage IVB
  • ​[Any T], [Any N], M1

Pathological (pTNM)

• stage 0
  • ​Tis, N0, M0, [G N/A]
• stage IA
  • T1a, N0, M0, [GX, G1]
• stage IB
  • T1a, N0, M0, G2
  • T1b, N0, M0, [GX, G1, G2]
• stage IC
  • T1, N0, M0, G3
  • T2, N0, M0, [G1, G2]
• stage IIA
  • T2, N0, M0, [GX, G3]
• stage IIB
  • T1, N1, M0, [Any G]
  • ​T3, N0, M0, [Any G]
• stage IIIA
  • T1, N2, M0, [Any G]
  • T2, N1, M0, [Any G]
• stage IIIB
  • ​T2, N2, M0, [Any G]
  • T3, [N1, N2], M0, [Any G]
  • T4a, [N0, N1], M0, [Any G]
• stage IVA
  • ​T4a, N2, M0, [Any G]
  • T4b, [N0, N1, N2], M0, [Any G]
  • [Any T], N3, M0, [Any G]
• stage IVB
  • ​[Any T], [Any N], M1, [Any G], [Any L]

Posttherapy pathological (ypTNM)

• stage I
  • [T0, T1, T2], N0, M0
• stage II
  • T3, N0, M0
• stage IIIA
  • [T0, T1, T2], N1, M0
• stage IIIB
  • ​T3, N1, M0
  • [T0, T1, T2, T3], N2, M0
  • T4a, N0, M0
• stage IVA
  • ​T4a, [NX, N1, N2], M0
  • T4b, [N0, N1, N2], M0
  • [Any T], N3, M0
• stage IVB
  • ​[Any T], [Any N], M1