Esophageal Flashcards
Epidemiology of esophageal cancer
Represents approximately 1% of all cancer diagnoses.
Men are three to four times more likely to develop esophageal cancer.
Most cancers are diagnosed between 55 to 85 years of age.
Greater frequency in northern china, northern Iran and South Africa has been attributed to nutritional and environmental factors.
Etiology of esophageal cancer
Squamous cell carcinoma: - excessive drinking and smoking Barret's esophagus - gastroesophageal reflux Adenocarcinoma - long-standing gastroesophageal reflux disease (30% of esophageal cancers are associated with GERD) Diet - diets low in fresh fruits and vegetables and high in nitrates (cured meats, pickled veggies) Other diseases - Achalasia - Tylosis
Achalasia
The lower two-thirds of the esophagus lose normal peristaltic activity. The esophagus becomes dilated and the esophagogastric junction sphincter fails to relax so food cannot pass to the stomach.
Tylosis
A rare inherited disorder that causes excessive skin growth on the palms of the hands and feet. Individuals with this disease see a 40% increased risk of esophageal cancer due to a mutation on the chromosome.
Prognostic indicators esophageal cancer
Tumour size is an important tool.
- smaller tumours are typically localized and have a better 2-year survival
- larger tumours typically have metastasized
Other factors:
- weight loss of 10%
- poor performance status
- age greater than 65 years
Anatomy of the esophagus
25cm long tube lined with stratified epithelium.
Begins at the level of C6 and traverses the thoracic cage to terminate in the abdomen at the esophageal gastric junction.
Three regions of the esophagus
Upper thoracic: SSN to the carina
Middle thoracic: begins at carina and extends to the esophageal gastric junction
Lower thoracic: includes the abdominal esophagus
Layers of the esophagus
Mucosa
Submucosa: circular layer
Muscular layer: longitudinal layer
* lacks a serosal layer, the outermost layer is called the adventitia, which consists of thin loss connective tissue. This is another factor that contributes to the early spread to adjacent structures.
Barrets Esophagus
Condition in which the distal esophagus is lined with columnar epithelium rather than stratified squamous epithelium.
Mucosal change typically occurs with gastrointestinal reflux.
Upper and middle thoracic esophagus lymph drainage
paratracheal lymph nodes hilar lymph nodes sub-carinal lymph nodes paraesophageal lymph nodes paracardial lymph nodes
The lower third of the esophagus lymph drainage
Celiac axis nodes
Left gastric nodes
Nodes of the lesser curvature of the stomach
Clinical presentation of the esophagus cancer
Dysphagia and weight loss occur in 90% of patients
Patients may feel the food sticking when swallowing
Regurgitation of undigested food may also occur
Odynophagia (painful swallowing occurs in 50% of patients)
Symptoms of a locally advanced tumour include:
- hematemesis (vomiting blood)
- coughing
- hemoptysis
Histologic confirmation of esophageal cancer
Esophagoscopy a rigid or flexible endoscope that can be used to examine the entire esophagus with brushing and biopsies done to suspicious lesions.
EUS
Endoscopic ultrasound scan: useful for visualizing the tumour and depth of invasion and lymph node status.
Pathology of esophageal cancer
Squamous cell carcinoma: more commonly found in the upper and middle esophagus
Adenocarcinoma: typically occurs in the distal esophagus and GE junction.
T1 stage esophagus
T1a: tumour invades lamina propria or muscularis mucosa
T2b: tumour invades submucosa
T2 stage esophagus
Tumour invades muscularis propria
T3 stage esophagus
Tumour invades adventitia
T4 stage esophagus
T4a: resectable tumour invades pleura, pericardium or diaphragm
T4b: unresectable tumour invading other adjacent structures such as the aorta, vertebral body, trachea etc.
N1 stage esophagus
regional lymph node metastasis involving 1 or 2 lymph nodes
N2 stage esophagus
regional lymph node metastasis involving 3 or 5 lymph nodes
N3 stage esophagus
Regional lymph nodes metastasis involving 7 or more lymph nodes
Spread of esophagus
Usually longitudinal/
Occasionally skip lesions may be present
Locally advanced disease invasion into adjacent structures and early spread to lymphatics is common.
Distant met locations of esophageal cancer
Liver and lung are most common
Surgery options for esophageal cancer
Patients who receive either surgery or RT have a high risk of local and distant recurrence.
Surgical resection is typically limited to the middle and lower thirds of the esophagus.
Curative surgery typically involves are esophagectomy, The entire esophagus is removed and the stomach or left colon is placed in the thoracic region.
Radiation therapy for esophageal cancer
Radiation + chemotherapy or preoperative chemoradiation is considered the best option to reduce the chance of local and distant recurrence.
Clinical treatment volume for esophageal cancer
Planning must take into account the longitudinal spread of esophageal cancers, the chance of skip lesions and the likelihood of lymph node involvement.
The treatment volume includes regional lymph nodes and encompasses the tumour with 3cm to 4cm margins above and below the tumour volume and a 1cm radial margin.
Field borders for upper 1/3 of esophagus lesions
The field begins at the thyroid cartilage and ends at the level of the carina to include:
- supraclavicular nodes
- low anterior cervical nodes
- mediastinal lymph nodes
field borders for distal 1/3 of esophagus lesion
Must include the celiac-axis nodes which are located at T12-L1. The superior aspect should include the paraesophageal nodes and mediastinal nodes.
Field borders for mid-thoracic esophagus lesions
Periesophageal lymph nodes and the mediastinal lymph nodes should be included.
Organs at risk esophageal treatment
Lung Heart Spinal cord Kidneys Liver
TDF for esophageal cancer
RT alone: 60 to 65Gy
Pre-operative chemoradiation: 41.4-50.4 Gy
Definitive chemoradiation: 50-50.4Gy
Side effects of esophageal cancer
After 2 weeks of RT:
- esophagitis: substernal pain when swallowing and the sensation of food sticking.
- treatment: small meals of soft pureed foods, can supplement with boosts.
- medication: liquid analgesics or viscous lidocaine
Pericarditis and pneumonitis may also occur if the lung or heart is in the field.
Late effects:
- stenosis
- stricture
Radiation tolerance of the esophagus
65Gy
With chemotherapy, it is reduced to 50Gy
