Oesophagogastric Surgery meets the needs of surgeons in higher training and practising consultants for a contemporary and evidence-based account of this sub-specialty that is relevant to their general surgical practice. It is a practical reference source incorporating the most current information on recent developments, management issues and operative procedures. The text is thoroughly referenced and supported by evidence-based recommendations wherever possible, distinguishing between strong evidence to support a conclusion, and evidence suggesting that a recommendation can be reached on the balance of probabilities.
This is a title in the Companion to Specialist Surgical Practice series whose eight volumes are an established and highly regarded source of information for the specialist general surgeon.
- The Companion to Specialist Surgical Practice series provides a current and concise summary of the key topics within each major surgical sub-specialty.
- Each volume highlights evidence-based practice both in the text and within the extensive list of references at the end of every chapter.
- An expanded authorship team across the series includes additional European and World experts with an increased emphasis on global practice.
- The contents of the series have been extensively revised in line with recently published evidence.
- This revised edition takes full account of the advances in the roles of endoscopic and laparoscopic investigation, management and the treatment of benign and malignant oesophagogastric disease.
- Key areas of evolving oesophagogastric practice are reflected in state of the art chapters from authors in the United States, Japan and Australia.
- Over half of the chapters have been updated to reflect the latest opinions on complicated and rapidly changing disciplines in endoscopic and open surgery
Pathology of oesophageal and gastric tumours
Heike I. Grabsch
Patients with neoplastic processes of the oesophagus most commonly present clinically at an advanced disease stage with strictures, plaque-like or polypoid masses protruding into the lumen, diffuse thickening of the mucosa and wall or deeply penetrating ulcers. Oesophageal neoplasms can be broadly divided into epithelial and mesenchymal subtypes according to the cell of origin. Whilst epithelial neoplasms are more common and can be recognised endoscopically due to mucosal irregularities, mesenchymal neoplasms are usually located subepithelially with an intact overlying mucosa. Precursor lesions have been recognised for malignant epithelial tumours and will be discussed in this chapter together with the histopathological features and molecular pathology of oesophageal tumours.
Epithelial tumours of the oesophagus and the gastro-oesophageal junction
Benign tumours and tumour-like lesions
Squamous cell papillomas are the most frequent benign epithelial tumours of the oesophagus, with a distinctive endoscopic appearance. They are most commonly located in the middle or lower third of the oesophagus, are exophytic, sessile or partly pedunculated, well demarcated and measure usually less than 5 mm in diameter. Only patients with very large lesions become clinically symptomatic. True adenomas of the oesophagus are benign tumours that develop from the submucosal oesophageal glands and are exceedingly rare.
Developmental cysts and congenital oesophageal duplications are benign lesions that may clinically mimic a tumour because of their mass effect, causing compression of the neighbouring respiratory tract. Similarly, patients with giant fibrovascular polyps, an entirely benign neoplasm, may present with severe dysphagia and respiratory symptoms and a large pedunculated mass obliterating the oesophageal lumen.
Squamous cell carcinoma
Squamous cell carcinoma is the most common malignant tumour of the oesophagus worldwide and affects men two to ten times more often than females, with an average age between 50 and 60 years at time of diagnosis. There is a marked geographic and ethnic variation in incidence. Incidence rates are highest in Iran, China, South America and Eastern Africa and are higher in African-Americans than Caucasian-Americans regardless of gender.
The aetiology and predisposing factors for oesophageal squamous cell carcinoma vary significantly in different regions of the world.1 Tobacco smoking and alcohol consumption are major risk factors for oesophageal squamous cell carcinoma.2,3
The intake of hot beverages has been shown to increase the risk of squamous cell carcinoma. Furthermore, dietary factors such as a lack of fresh fruit and vegetables and high intake of barbecued meat or pickled vegetables most likely play a role in the aetiology of squamous cell carcinoma. Human papilloma virus infection has been implicated in the pathogenesis of oesophageal squamous cell carcinoma, but its precise role is still controversial at present. Patients with achalasia have an increased risk of developing cancer compared to the normal population.4 The risk of developing oesophageal carcinoma is also increased in patients with coeliac disease,5 Plummer–Vinson syndrome (also called Paterson–Kelly syndrome),6 tylosis (also called focal non-epidermolytic palmoplantar keratoderma),7,8 previous ingestion of corrosive substances,9 Zenker's diverticulum10 or after ionising radiation.11 In the Asian population, polymorphisms in ALDH1B1 and ALDH2, both genes encoding aldehyde dehydrogenases, are associated with squamous cell carcinoma.12
Oesophageal squamous cell carcinomas are found in the upper, middle and lower third of the oesophagus in a ratio of approximately 1:5:2. The macroscopic appearance depends on the depth of tumour invasion and is classified into four different types according to the Japanese classification for oesophageal cancer,13 which is similar to the macroscopic classification of gastric cancer (see Fig. 1.8 below). Approximately 60% of squamous cell carcinomas show an exophytic or fungating growth pattern, 25% are ulcerative and 15% are infiltrative (Fig. 1.1). However, the macroscopic appearance of all cancers can significantly change as a result of neoadjuvant chemotherapy or chemoradiation, with tumour shrinkage, extensive necrosis and fibrosis.
Figure 1.1 Oesophageal squamous cell carcinoma located in the middle oesophagus. (a) Fresh oesophagectomy specimen with a polypoid exophytic tumour growth and a smaller flat (red coloured) mucosal abnormality. (b) Lack of (dark) iodine staining in the abnormal areas. (c) Same specimen after fixation. Courtesy of Dr Tomio Arai, Tokyo.
Figure 1.8 (a) Borrmann classification for advanced cancers. Type I: polypoid with a broad base, may be superficially ulcerated. Type II: excavated ulcerated lesion with elevated borders, sharp margin with no definitive infiltration into adjacent mucosa. Type III: ulcerative, diffusely infiltrating base. Type IV: diffusely infiltrative thickening of the wall (linitis plastica). (b) Murakami classification for early cancers. Modified from Japanese Gastric Cancer Association. Japanese classification of gastric carcinoma, 3rd English edn. Gastric Cancer 2011; 14(2):101–12.
Squamous cell carcinomas invade both horizontally and vertically. In the West, 60% of patients have carcinomas that have invaded beyond the muscularis propria and have regional lymph node metastases at the time of diagnosis, whereas in Japan up to 40% of all resected carcinomas are superficial or early carcinomas involving mucosa and submucosa only.14 The frequency of lymph node metastases is related to the depth of tumour invasion and has been reported as less than 5% for intramucosal carcinomas and up to 45% for submucosal carcinomas. Although tumours located in the upper third of the oesophagus are more likely to spread to cervical and upper mediastinal nodes, a significant proportion will also spread to perigastric nodes.
Tumours located in the middle and lower oesophagus can spread to upper mediastinal and perigastric nodes, and patients with lymph node metastases on both sides of the diaphragm have been shown to have a poorer prognosis.15–17
Distant metastases due to haematogenous spread are most commonly found in liver, lung, adrenal gland and kidney.18
Histologically, squamous cell carcinomas are characterised by keratinocyte-like cells that may or may not have intercellular bridges and show a variable degree of keratinisation (Fig. 1.2). Depending on the extent of mitotic activity, nuclear atypia and degree of squamous differentiation including degree of keratinisation, squamous cell carcinomas are graded as well, moderately or poorly differentiated.12 The histology of squamous cell carcinoma can change dramatically after neoadjuvant chemo(radio)therapy and then typically shows extensive necrosis, inflammation, fibrosis and foreign body-type granulomas around keratin pearls. There is currently no consensus on how to grade tumour regression. The regression grading according to Mandard et al.19 considers the relative proportion of residual viable tumour cells and fibrosis in the primary cancer and is probably currently the one most commonly used in the UK. Very recently, a grading system to assess tumour regression in lymph nodes has been proposed and showed prognostic significance in a small series of patients.20
Figure 1.2 Histological images from specimen in Fig. 1.1. (a) Histology of the nodule shows poorly differentiated squamous cell carcinoma with no evidence of keratin formation and necrosis (pink material) between strands of neoplastic cells. (b) Histology of the flat lesion shows early infiltrative squamous cell carcinoma. Courtesy of Dr Tomio Arai, Tokyo.
Three main variants of squamous cell carcinoma have been described:12
1. Verrucous carcinoma of the oesophagus is a rare, locally aggressive tumour that is more common in males. Macroscopically, the tumour has an exophytic papillary appearance and tumours are usually very large before they become clinically apparent. Microscopically, the tumour is very well differentiated with minimal atypia. Superficial biopsies are often insufficient to distinguish between a squamous papilloma, pseudoepitheliomatous hyperplasia and verrucous carcinoma.21
2. Spindle cell carcinoma (also known as carcinosarcoma, sarcomatoid carcinoma and polypoid carcinoma) is a polypoid tumour located in the middle or lower third of the oesophagus. Histologically, the tumour is a mixture of a well-differentiated squamous cell carcinoma and a high-grade spindle cell component that can show osseous, cartilaginous or skeletal muscle...