Esophageal Cancer





Esophageal cancer is an uncommon malignancy that ranks sixth in terms of mortality worldwide. Squamous cell carcinoma is the predominant histologic subtype worldwide whereas adenocarcinoma represents the majority of cases in North America, Australia, and Europe. Esophageal cancer is staged using the American Joint Committee on Cancer and the International Union for Cancer Control TNM system and has separate classifications for the clinical, pathologic, and postneoadjuvant pathologic stage groups. The determination of clinical TNM is based on complementary imaging modalities, including esophagogastroduodenoscopy/endoscopic ultrasound; endoscopic ultrasound–fine-needle aspiration; computed tomography of the chest, abdomen, and pelvis; and fluorodeoxyglucose PET/computed tomography.


Key points








  • Squamous cell carcinoma and adenocarcinoma represent more than 90% of cases of esophageal cancer, the latter of which is the most prevalent histologic subtype in North America.



  • The most commonly used scheme for staging esophageal cancer is the eighth edition of the American Joint Committee on Cancer/The International Union for Cancer Control TNM system.



  • The T category ranges from Tis (high-grade dysplasia) to T4 (invasion of the primary tumor into adjacent structures).



  • The N category is subdivided into the following components based on the number of involved regional lymph nodes: N1—1 to 2 lymph node metastases, N2—3 to 6 lymph node metastases, and N3—greater than 6 lymph node metastases.



  • The M category includes M0 (no metastasis) and M1 (nonregional lymph nodal metastasis and distant visceral metastasis) subcategories.




Introduction


Esophageal cancer is a relatively uncommon malignancy in the United States, although its incidence has been increasing since the 1980s. It currently ranks seventh in terms of incidence and sixth in overall mortality worldwide. The 2 most common histologic types of esophageal cancer are squamous cell carcinoma (SCC) and adenocarcinoma (AC), representing more than 90% of all cases. SCC accounts for more than 80% of all cases worldwide and is the predominant histologic type in less developed countries. In contrast, AC represents more than 60% of all cases in North American, Australia, and Europe. ,


The treatment of esophageal cancer is stage-specific in order to ensure the best possible clinical outcomes. The treatment plan typically includes surgical resection for early disease, multimodality treatment with neoadjuvant chemotherapy, or combined chemoradiotherapy followed by surgery for patients with locally advanced cancer and systemic therapy for patients with metastatic disease. Accordingly, accurate pretreatment staging is important to ensure the development of appropriate treatment plans. The most commonly used staging for esophageal cancer is the eighth edition of the American Joint Committee on Cancer (AJCC)/The international Union for Cancer Control (UICC) TNM system. TNM staging includes determination of the depth of local invasion by the primary tumor (T), the presence and number of regional lymph nodes involved (N), and the presence or absence of distant metastasis (M). Because of differences in epidemiology, pathogenesis, location, and outcomes of the major histologic subtypes, TNM staging is separate for AC and SCC and takes into account the differences in prognosis between clinically and pathologically staged patients. In this regard, clinical (cTNM) staging before treatment and pathologic (pTNM) staging after surgical resection are used. The eighth edition of the TNM system also includes an additional stage grouping for patients who have undergone neoadjuvant therapy and surgical resection (ypTNM).


Tumor-Node-Metastasis Staging System


Categories and subcategories are used in cTNM, pTNM, and ypTNM staging. The T category represents the primary tumor, and the subcategories describe the depth of local invasion (T1–T4). Lymph node metastasis is designated by the N category, and the subcategories (N0–N3) describe the number of regional lymph nodes. The M category represents distant metastatic disease and includes subcategories describing its absence (M0) or presence (M1) ( Fig. 1 ). Nonanatomic categories comprise histologic cell type, grade of differentiation (G), and location (L) of the primary tumor. Categories G and L are used only for pTNM. These anatomic and nonanatomic categories and subcategories are used to determine cTNM (based on imaging studies and histology obtained by biopsies) ( Table 1 ) and pTNM ( Table 2 ) and ypTNM (both based on pathology of the resected specimen) ( Table 3 ).




Fig. 1


TNM anatomic categories include the primary tumor (T), regional lymph node (N), and distant metastases (M). The T category provides information regarding the extension of tumor invasion into the esophageal wall. The N category represents regional lymph node involvement, and the M category represents metastasis to distant organ/s.


Table 1

Clinical TNM stage groups






























































Clinical TNM Adenocarcinoma
Stage T N M
0 Tis N0 M0
I T1 N0 M0
IIA T1 N1 M0
IIB T2 N0 M0
III T2–3 N1 M0
T3–4a N0–1 M0
IVA T1–4a N2 M0
T4b N0–2 M0
T1–4 N3 M0
IVB Any T Any N M1



































































Clinical TNM Squamous Cell Carcinoma
Stage T N M
0 Tis N0 M0
I T1 N0–1 M0
II T2 N0–1 M0
T3 N0 M0
III T3 N1 M0
T1–3 N2 M0
IV T4 N0–2 M0
IIIA T1–T2 N2 M0
T1–4 N3 M0
IVA T4 N0–2 M0
IVB Any T Any N M1

The cTNM is separate for AC and SCC, given the differences in epidemiology, pathogenesis, location and outcomes of both subtypes. cTNM is based on imaging and biopsy specimens.


Table 2

Pathologic TNM stage groups

























































































































Pathologic TNM Adenocarcinoma
Stage T N M G
0 Tis N0 M0 N/A
IA T1a N0 M0 G, X
IB T1a N0 M0 G2
T1b N0 M0 G1–2, X
IC T1 N0 M0 G3
T2 N0 M0 G1–2
IIA T2 N0 M0 G3, X
IIB T1 N1 M0 Any
T3 N1 M0 Any
IIIA T1 N2 M0 Any
T2 N0–1 M0 Any
IIIB T4a N1–2 M0 Any
T3 N1 M0 Any
T2–3 N2 M0 Any
IVA T4a N2 M0 Any
T4b N0–2 M0 Any
T1–4 N3 M0 Any
T1–4 N0–3 M1 Any


























































































































































Pathologic TNM Squamous Cell Carcinoma
Stage T N M G Location
0 Tis N0 M0 1, X Any
IA T1a N0 M0 G1, X Any
IB T1b N0 M0 G1, X Any
T1 N0 M0 G2–3 Any
T2 N0 M0 G1 Any
IIA T2 N0 M0 G2–3, X Any
T3 N0 M0 G1 Upper/middle
IIB T3 N0 M0 G2–3 Upper/middle
T3 N0 M0 X Any
T3 N1 M0 Any X
T1 N1 M0 Any Any
IIIA T1 N2 M0 Any Any
T2 N1 M0 Any Any
IIIB T4a N0–1 M0 Any Any
T3 N1 M0 Any Any
T2–3 N2 M1 Any Any
IVA T4a N2 M0 Any Any
T4b N0–2 M0 Any Any
T1–4 N3 M0 Any Any
IVB T1–4 N0–3 M1 Any Any

Only gold members can continue reading. Log In or Register to continue

Stay updated, free articles. Join our Telegram channel

Apr 19, 2021 | Posted by in GENERAL RADIOLOGY | Comments Off on Esophageal Cancer

Full access? Get Clinical Tree

Get Clinical Tree app for offline access