Cancers of the oesophagus and stomach are among the most lethal of all malignancies. The majority of these neoplasms in Western countries are detected at an advanced stage due to the insidious nature of the onset of symptoms and their similarity in early stages to benign causes of dysphagia and dyspepsia. Only by earlier diagnosis, more accurate staging methods, and more effective treatment protocols can we offer any hope of improving the dismal prognosis of these tumours.

In the past, squamous cell carcinoma accounted for over 95% of oesophageal malignancies. Over the past two decades, however, there has been a dramatic increase of adenocarcinoma arising in columnar cell-lined Barrett’s mucosa, accounting for greater than 50% of all oesophageal cancers in some areas [1].

Early adenocarcinoma arising from Barrett’s mucosa can manifest as small sessile polyps, plaque-like lesions, or superficial spreading lesions that cause focal nodularity of the mucosa without a discrete mass. These early cancers can also cause focal irregularity, flattening or nodularity of a pre-existing peptic stricture. Accordingly, early endoscopy and biopsy are necessary to exclude adenocarcinoma whenever any of these suspicious features develop in the region of a peptic stricture. Advanced adenocarcinoma of the oesophagus can appear infiltrating, polypoid, ulcerative, or, less commonly varicoid (Fig. 1) [2].

Figure 1 Carcinoma of the oesophagus on double contrast barium studies. (A) Squamous cell carcinoma showing luminal narrowing, abrupt shelf-like borders, ulceration, circumferential growth and a fistula to the tracheobronchial tree. (B) Adenocarcinoma arising (more ...)

Cancers of the antrum and body of the stomach have decreased in incidence in Western countries but the incidence of adenocarcinomas at the gastro-oesophageal junction have been dramatically rising. Early gastric cancer can only be found by screening asymptomatic, at-risk patients.

Type 1 advanced gastric cancer is a large polypoid or fungating lesion that has irregular lobulation and measures 3 cm or larger in greatest diameter. In Type 2 advanced gastric cancer, the bulk of the tumour has been replaced by ulceration. These tumours have discrete, sharply defined borders. Type 3 advanced gastric cancers have mixed morphology with both infiltrative and ulcerative components. The ulceration does not have discrete borders, however. Type 4 advanced gastric cancers are diffusely infiltrating lesions that are associated with marked proliferation of fibrotic tissue and desmoplasia producing the so-called linitis plastica appearance (Fig. 2) [3].

Figure 2 Adenocarcinoma of the stomach. (A) Early gastric cancer with mucosal nodularity. (B) Advanced gastric cancer with narrowing and rigidity of the antral wall due to mural infiltration of scirrhous tumour.

Once the diagnosis of oesophageal and gastric cancer is established, accurate staging is essential in planning the surgical approach, in deciding whether neoadjuvant chemotherapy or radiation therapy is necessary, and in determining the risk of tumour recurrence and overall prognosis.

A number of imaging examinations have proven useful for upper gastrointestinal tumour staging [4–8]:

• (1) MDCT
• (2) MRI
• (3) endoluminal MRI
• (4) transabdominal ultrasound
• (5) endoscopic ultrasound
• (6) intraoperative ultrasound
• (7) PET
• (8) PET/CT.

Figure 3 Schematic showing T staging of oesophageal and gastric cancer. T1, tumour extends into submucosa; T2, tumour extends into muscularis propria; T3, tumour extends through the muscularis propria into the subserosa; T4, tumour extends directly into other (more ...)

Figure 4 Endoscopic ultrasound demonstrates a T2 oesophageal neoplasm that has invaded but has penetrated beyond the muscularis propria.

Figure 5 N staging of oesophago-gastric neoplasm. Schematic diagram depicting common sites of lymph node metastases in oesophageal and gastric cancers.

Figure 6 CT scan shows extensive adenopathy in the gastro-hepatic ligament due to spread of an adjacent gastric neoplasm.

Endoscopic ultrasound is superior to MDCT, conventional MR and endoscopic MR in the depiction of local adenopathy. PET/CT is superb for detecting regional and distant adenopathy.

MDCT is the standard means of M staging in most situations. It is superior to MR in depicting mediastinal, hilar, pulmonary, pericardial, pleural, omental, mesenteric and peritoneal disease. PET/CT appears to be the most accurate means of globally evaluating the chest and abdominal cavities for metastatic tumour. Intraoperative ultrasound appears to be the most sensitive technique in the depiction of liver metastases (Fig. 7).

Figure 7 PET scan showing a tumour of the oesophago-gastric junction with metastatic disease to the liver.