Current Status and Future Prospects for Esophageal Cancer

Abstract

Esophageal cancer (EC) is the ninth most common cancer and the sixth leading cause of cancer deaths worldwide. Esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) are the two main histological subtypes with distinct epidemiological and clinical features. While the global incidence of ESCC is declining, the incidence of EAC is increasing in many countries. Decades of epidemiologic research have identified distinct environmental exposures for ESCC and EAC subtypes. Recent advances in understanding the genomic aspects of EC have advanced our understanding of EC causes and led to using specific genomic alterations in EC tumors as biomarkers for early diagnosis, treatment, and prognosis of this cancer. Nevertheless, the prognosis of EC is still poor, with a five-year survival rate of less than 20%. Currently, there are significant challenges for early detection and secondary prevention for both ESCC and EAC subtypes, but Cytosponge™ is shifting this position for EAC. Primary prevention remains the preferred strategy for reducing the global burden of EC. In this review, we will summarize recent advances, current status, and future prospects of the studies related to epidemiology, time trends, environmental risk factors, prevention, early diagnosis, and treatment for both EC subtypes.

Keywords: adenocarcinoma; epidemiology; prevention; risk factors; squamous cell carcinoma.

Figure 1

(A) Country-level male-to-female ratio (MFR) for esophageal cancer (EC) versus a country’s Human Development Index. (B) Country-level age-standardized incidence rates (ASR) for esophageal cancer among men versus rates among women. Both plots are color-coded according to categories of the MFR as indicated. Data source: Globocan 2020.

Figure 2

High incidence areas of esophageal cancer (EC) in Eastern and South-Central Asia (Asian EC belt) and Eastern and Sothern Africa (African EC corridor).

Figure 3

(A,B) Chromoendoscopy with acetic acid using narrow-band imaging and Lugol’s iodine staining both increase identification of HGD and early ESCC, which makes targeted biopsy for diagnosis and ablation or resection of HGD the precursor of ESCC possible. (C) Endoscopic image of Barrett’s esophagus visible as a salmon-colored metaplastic epithelium (columnar) replacing the normal bright-pink epithelium of the distal squamous esophagus.

Figure 4

Cytosponge™ capsule with string is swallowed with 150 mL of water. After 5 min, the gelatin coat of the capsule will be dissolved, and the sponge that is inside the capsule will be released. The sponge gathers cells from the esophagus and gastroesophageal junction upon retrieval by pulling the string. The retrieved and expanded sponge is placed in a preservative fluid and transferred to the laboratory for cytological examination and staining.