Oesophageal cancer

From greek.doctor

There are two major types of oesophageal cancer, adenocarcinoma and squamous cell carcinoma. Both type typically affect elderly men. Oesophageal adenocarcinoma evolves from the Barrett-mucosa and is the most common type of oesophageal cancer in the Western world. Its incidence is rising. It’s usually found in the lower part of the oesophagus.

Oesophageal SCC is more common in developing countries, and the most common type overall. It’s usually found in the middle and upper parts of the oesophagus. Its prognosis is worse than adenocarcinoma.

It’s usually asymptomatic in the early stages, and therefore is rarely discovered until the late stages. In the late stages it may present with non-specific symptoms like weight loss, dysphagia, and dyspepsia. At the time of presentation, most patients already have advanced cancer.

Etiology

Because adenocarcinoma evolves from GERD and Barrett oesophagus, the risk factors are the same as for GERD, especially smoking.

The risk factors for SCC are:

  • Alcohol consumption
  • Smoking
  • Diet low in fruits and vegetables
  • Exposure to nitrosamines in diet
  • Frequent consumption of very hot beverages, like the coffee at McDonalds.

Clinical features

Both types of oesophageal cancer have similar clinical features. It’s usually asymptomatic in the early stages, and therefore is rarely discovered until the late stages. In the late stages it may present with non-specific symptoms like dysphagia, odynophagia, cough, weight loss, and dyspepsia.

At the time of presentation most patients already have advanced cancer.

Diagnosis and evaluation

Upper endoscopy is the investigation of choice, as it allows for both visual diagnosis and biopsy. After the diagnosis is made, the most important is to determine the tumour’s resectability. Endoscopic ultrasound (EUS) is the preferred method for this, as it’s the most accurate technique for staging the tumour locally (T) and regionally (N). EUS can separate T1A and T1B stages.

CT thorax and abdomen is required for staging. Bronchoscopy is required if extension into the bronchial system is suspected.

Treatment

Proper evaluation and staging are essential to determine the resectability of the disease. Only around 1/3 of patients are operated on.

In the rare case where very early cancers are discovered, we may use minimally invasive methods like endoscopic resection or laser ablation. Locally advanced oesophageal cancer is treated with neoadjuvant chemoradiation, followed by surgery if the tumour is considered resectable on restaging, possibly followed by adjuvant chemotherapy.

Radiochemotherapy, targeted therapy, or immunotherapy may be used as palliative therapy for stage IV (advanced) disease. The placement of an oesophageal stent to keep the lumen open is an important palliative treatment option for oesophageal cancer, allowing for continued passage of food.

Surgery

Most patients present in a stage where radical surgery is required for cure. However, oesophageal resection is a large and complicated procedure, and patients often develop post-operative complications like nutritional problems, stenosis in the anastomosis, and slow passage of foodstuffs. After surgical resection of the oesophagus, either total or partial, the resected part of the oesophagus should be substituted with stomach (first choice) or colon. Because of the localisation of the oesophagus, oesophageal surgery may involve the neck, thorax, and/or the abdomen, making for a large and complicated surgery.

Surgery may be performed open, laparoscopically, or in combination.

Systemic therapy

Chemotherapy, most commonly the FLOT regimen, is commonly used in oesophageal cancer. In case of HER2 overexpression, trastuzumab (an anti-HER2 antibody) may be used as targeted therapy. In case of PD-L1 overexpression, pembrolizumab may be used as immunotherapy.

Radiotherapy

Radiotherapy is often combined with chemotherapy for oesophageal cancer.

Prognosis

The prognosis is very poor, with a 5-year survival of 15%. The 5-year survival of patients treated with curative surgery is around 30 – 40%. Squamous cell carcinoma has a worse prognosis than adenocarcinoma.