Esophageal Cancer - MU

Esophageal Cancer

• Esophageal cancer is reviewed, with key information about surgical anatomy, vasculature, and nerve supply

Esophagus Anatomy

• The esophagus is about 25 cm long, extending from the cricopharyngeal sphincter to the cardio-esophageal junction.
• The esophagus runs in the posterior mediastinum as a continuation of the pharynx.
• Approximately 2 cm of the esophagus lies below the diaphragm.
• Anatomically, the cardio-esophageal junction lies to the left of the thoracic vertebra number 11.
• Endoscopically, the junction is identified by a Z-line, where the esophageal mucosa changes to the gastric mucosa.
• The Collar of Helvetius marks where the esophagus's circular muscles turn into the stomach's oblique muscles at the incisura.

Physiological Constrictions

• The esophagus has 3 constrictions
• The cricopharyngeal constriction is 15 cm from the incisor teeth and has a diameter of 14 mm and can cause foreign body lodgement
• The aortic and bronchial constriction is 25 cm from the incisor teeth and has a diameter of 15-17 mm and this area is prone to perforation during endoscopy
• The diaphragmatic sphincter is 40 cm from the incisor teeth, has a diameter of 16-19 mm and is linked to malignancy

Vasculature and Nerve Supply

• The cervical esophagus is mainly suppliedby branches of the inferior thyroid artery.
• The upper thoracic esophagus is supplied mainly from branches of the inferior thyroid artery, and less consistently from an anterior esophago-tracheal branch from the aorta.
• The mid and lower thoracic esophagus is supplied by bronchial arteries.
• The lower esophagus receives small branches of the left gastric artery.
• Azygos and hemiazygos veins drain the thoracic esophagus.
• Veins accompany arteries
• Rich internal arterial anastomosis is present in the esophagus and the stomach allowing for extensive mobilization of the esophagus without compromising viability.
• Lymphatics:
  • The upper esophagus drains into the left and right supraclavicular nodes.
  • The middle esophagus drains into the tracheobronchial and paraoesophageal nodes.
  • The lower esophagus drains into LNs along the lesser curvature of the stomach and then into coeliac nodes.
  • Involvement of coeliac nodes indicates inoperability.
• Parasympathetic supply is from the vagus nerve and includes extrinsic/intrinsic plexuses.
  • The intrinsic plexus lacks Meissner's network.
  • Auerbach's plexus is only present in the lower two-thirds.

Surgical Anatomy Key Points

• Upper esophageal sphincter: dense cricopharyngeus muscle leads to Zenker's diverticulum through Killian triangle
• Lower esophageal sphincter: high pressure zone at gastro-oesophageal junction. Weakness causes reflux oesophagitis
• Oesophageal mucosa: important in oesophageal anastomosis
• No serosa, no mesentery: mobilization is required and the leak rate is high, so easy spread of carcinoma.
• Helicoidal muscle: helps peristalsis, but it recoils due to elasticity. Post resection, the specimen shortens and anastomosis may become difficult.
• Segmental arterial supply: extensive mobilization can be done without compromising blood supply for transhiatal esophagectomies
• Lower end of oesophagus-veins: rich intercommunicating veins between portal and systemic veins resulting in oesophageal varices occurring
• Azygos vein crossing oesophagus in thorax are prone to injury and bleeding making midoesophageal tumours form
• Mucosal & submucosal lymphatics out number capillaries so Oesophageal tumours extend over a long distance within oesophageal wall, requiring total oesophagectomy, cervical anastomosis, & lymph node clearance.

Histology

• Layers consist of an inner circular layer and outer longitudinal layer.
• Muscle Type:
  • Upper 1/3: Striated muscle fibers
  • Lower 2/3: Smooth muscle fibers Clinically significant motility disorders affect lower 2/3 (smooth muscle) of esophagus.
• Lining:
  • The entire esophagus is lined by squamous epithelium.
  • Except last 3 cm which is lined by columnar cells "The columnar cells are similar to gastric mucosa, but oxyntic & peptic cells are absent".
• Mucosa is the toughest coat of esophagus and is transformed into rugal folds.

Oesophageal Tumours

• Benign tumors are rare, occurring in less than 0.5% of cases
  • Epithelial: hyperplastic polyps, papilloma, and adenoma.
  • Stromal: leiomyoma, granular cell tumor (schwannoma), & lipoma.
• Malignant
  • SCC (squamous cell carcinoma) in the upper 2/3
  • Adenocarcinoma in the lower 1/3
  • Melanoma, Lymphoma, leiomyosarcoma, liposarcoma & special type: GIST

Benign Esophageal Tumors

• Leiomyoma is the most common kind
• Usually arises in the distal third with intact overlying mucosa
• Symptoms: asymptomatic for a long time, until it reaches an enormous size to cause dysphagia
• Diagnosis:
  • Barium swallow.
  • Endoscopy reveals "smooth submucosal lesion" + biopsy.
  • CT chest reveals its exact extent.
• Treatment:
  • Small lesions (< 5 cm): Enucleation.
  • Larger lesions: Esophagectomy.

Carcinoma of Esophagus: Epidemiology

• Most patients are above 50 years old
• Overall Male:Female is 3:1
• Gender incidence:
  • Lesions of cervical region: Females > Males.
  • Lesions of Thoracic & abdominal oesophagus: Males > Females.
• Site incidence:
  • Lower third of the oesophagus is more common than the upper two thirds
  • Worldwide, most esophageal cancers are squamous cell carcinoma.
  • In most Western countries, More than 70% are adenocarcinomas.
• Shift is mainly due to smoking, alcohol and Barrett's oesophagus
• Some improvement in diagnosis and treatment

Etiopathogenesis

• The exact etiology is unknown
• Precancerous/predisposing conditions:
  • GORD (Gastroesophageal reflux disease)
  • Plummer-Vinson syndrome
  • Achalasia of cardia
  • Familial keratosis palmaris or plantaris (tylosis) which is an autosomal dominant trait and increases esophageal cancer
• Exposure to Carcinogens:
  • Tobacco, heavy smoking, and abuse of alcohol increases squamous cell carcinoma and adenocarcinoma by 20-25%
  • Human papilloma virus (HPV) infection increases squamous cell carcinoma
    • Risk for cervical and oropharyngeal cancers also.
  • Dietary carcinogens/squamous cell carcinoma: elevated nitrates, fungi, and baked bread

Factors

• Squamous cell carcinoma:
  • Hovels-Evans syndrome or tylosis in 40 to 60% develop cancers and is called familial keratosis plantaris
  • Lye strictures up to 30% and forms 40 to 50 years after. Located in the middle third of the esophagus.
  • Achalasia, esophageal web, Plummer-Vinson syndrome, short esophagus, peptic esophagitis and patients with celiac disease.
• Adenocarcinoma
  • Barrett's esophagus, obesity (7-fold greater risk), reflux esophagitis, low socioeconomic status, and helicobacter pylori infection: inversely associated with the risk of adenocarcinoma

Sites

• 17% of cases occurs in the the upper 1/3 of oesophagus
• 50% of cases occurs in the the middle 1/3 of oesophagus
• 33% of cases occurs in the the lower 1/3 of oesophagus

Histopathological features of esophageal carcinoma

• Squamous cell carcinoma:
  • Epitheliomatous ulcer (carcinomatous): raised edges and flat base
  • Proliferative growth (Cauliflower): surface ulcer and commonly bleeds
  • Infiltrative (Annular stenosing) variety: early dysphagia (circumferential and longitudinal spread)
  • Polypoidal lesion: 5 year survival 70%
• Adenocarcinoma: lower end & middle esophagus (Barrett's esophagus)
• Sarcoma (leiomyosarcoma)
• Carcinosarcoma (best prognosis)
• Primary malignant melanoma and lymphoma
• Carcinoid

Macroscopic Features

• Visible lesions are advanced macroscopically/radiologically
• May be Fungating, Ulcerative, or infiltrative

Spread

• Starts as mucosal ulceration that spreads to the submucosa
• Advances, causing fibrosis and narrowing the lumen
• Then spreads to structures nearby
• Local Spreads
  • Tracheo-esophageal fistula: develops from carcinoma in the upper 3rd esophagus when trachea is involved.
  • Broncho-esophageal fistula: develops from carcinoma in the middle 3rd esophagus when bronchus is involved.
  • Esophago-aortic fistula: results in massive bleeding and is a cause of death and contraindications for surgery/radiotherapy.
• Lymphatic spread: better outcome if metastasis to 5 or fewer lymph nodes
• Blood spread:
  • Secondaries in the liver that appear nodular
  • Ascites and rectovesical deposits occur later
  • Lung metastasis
  • Palpable left supraclavicular nodes indicates advanced disease and this sign is called Troisier's sign.

Aggressive Behaviour Factors

• Lack of serosal layer
• Proximity of vital structures
• Extensive mediastinal lymphatic drainage
• Late presentation

Complications

• Neurological complications
  • Recurrent laryngeal nerve paralysis
  • Phrenic nerve paralysis → Hiccough & diaphragmatic paralysis
• Respiratory complications
  • Pneumonia, Mediastinitis, Empyema, and Purulent pericarditis
  • Erosion of the aorta (rare) → massive bleeding

Features of Unresected Cancer

• Death
• Obstruction, malnutrition, dehydration, anemia, cachexia

Diagnosis

• Age & sex is men > 60 years
• Progressive development takes place over 18 months
• Affects solids
• 60% of the circumference of the lumen must be involved for growth
• Dysphagia is a late symptom
• Dysphagia
  • Short duration
  • Solid food but progressively worsens
  • Progressive
• Other symptoms
  • Regurgitation & loss of appetite, weight loss/cachexia
  • Haematemesis is rare
  • Melaena is rare
• Pain
  • Backache indicates enlarged (coeliac) lymph nodes.
• Other system affection
  • Aspiration Pneumonitis & fetor hepaticus
  • Hoarseness, and cervical lymph nodes enlargement

Investigations

• CBC: Hb% is low due to generalized weakness.
• Liver function test (LFT) shows if secondary liver problems occurs (increased ALP).
• Take tumor markers

Radiological Testing

• Done to rule out:
  • Liver and peritoneal secondaries.
  • Lymph nodes in the porta hepatis, coeliac nodes, etc
• Uses fungating or ulcerating irregular persistent intrinsic filling defects and identifies if they deviate
• Barium swallow demonstrates
• Also look for abnormal 'axis', deviation or angulation to demonstrate fistulas
• Detect local infiltration, tumor and liver spread and involvement in the tracheobronchial tree
• Assesses vital structures. and fat
• PET scans are computerized tomography scans that are based on the principle of active tumor cells, is used on lymph nodes, and shows them differentiating, if cancerious or noncancerious and it's response to radio therapy or chemotherap

Oesohagoscopy

• It confirms the diagnosis in more than %90 and confirm cancer
• The addition of brush cytology specimens and seven biopsies
• Is addition of 100% if the lesions thought the addition of lesions thought to seven were the biopsy's

PET Scan Uses

• Finds 'endosono' when more than 5 lymph nodes are not a case for curative resection. Is also a high frequency and good transducer
• Bronchoscopy is used to find if that the tumour is local

Important to Decide in Investigations:

• To resect or not
• Is it worth the resecting
• Can the patient tolerate the procedure
• If the absent of systemic spread

Staging

• Factors deciding the choice of therapy
• General health of patient
• Co-morbid conditions and fitness.

1. General Features In Staging

• Operative risk, spread
• Multiple nodes on CT scan
• Tumor length greater than 20%

TNM Staging

• TO is no evidence of tumor
• Tls is carcinoma and tumor with lamina pro.
• Tis means no primary tumor
• Nx. Lymph cannot be assessed
• No. Lyph

Treatment

• Is main maintenance treatment and ongoing consequence with nutritional status
• Upper and lower tumours are also to be removed to cure

Principle Management:

• Metastatic and locally enavsive disease
• Neoadjuvant followed by esophagectomy. And manage nodes and A and B Lesions

Radiotherapy and Surgery:

• For the primary tumour, the resection that is done has to have 10cm proximally and 5 distal to the tumour.

Standard Esophagectomy:

• Midline laparotomy, followed by distal oesophagus mobilisation and a resection
• Stomach mobilisation
• Thoracotomy mobilises thoracic oeosphagus and mediastinal nodes,
  • Left thoracotomy, the proximal is below
  • Right thoracotomy approaches, Ivor Lewis approach where aortic arches are used to reach proximal

Other approaches:

• Additional cervical incisions are preformed so an oesophagogastric anastomosis
• A transhiatal approach which mobilizes by brunt dissection from the hiatus and at the cervical incision
• Minimally invasive robotic surgery
• Oesophageal replacement replaces the stomach via gastric pull up
• Mobilizes both right gastropeploic vessel the segment segments as a connector
• Oesophageal jeyunal flaps separate segments using a microvascular technique
• Then used like radiotherapy and surgery
• Useful at surgeries
• Mainly for the cells that are squamous c and other cancerous cells