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Scanning electron microscopy of Barrett's esophageal mucosa
0016-5107/79/2503-0092$02.00/0 GASTROINTESTINAL ENDOSCOPY Copyright © 1979 by the American Society for Gastrointestinal Endoscopy
Scanning electron microscopy of Barrett's esophageal mucosa Jagdish c. Mangla, MD Chung-Seng Lee, MD Rochester, New York
The morphologic features of Barrett's esophagus as depicted by scanning electron micrography are compared with those of normal esophageal and normal gastric mucosa. The authors conclude that the shaggy, denuded, irregular configuration of Barrett's esophageal mucosa may render it liable to ulceration, bleeding, stricture, and neoplasm.
The normal adult human esophagus is lined by stratified squamous epithelium. In Barrett's esophagus the normal stratified squamous epithelium is replaced by columnar epithelium. First described by N. R. Barrett,l this condition was considered as an esoteric and rare pathologic entity, but lately it is being reported frequently. The mucosa of Barrett's esophagus is prone to bleeding, ulceration, inflammation, and stricture formation. 2 - 6 It has become of increasing concern because supervening adenocarcinoma has been reported in as many as 8.5% of cases.? The histologic spectrum of Barrett's esophagus has been well described. B • a There are few reports of scanning electron microscopy (SEM) of normal esophagus. 9 - 11 One report describes the findings in 2 normal human volunteers and compares these findings to the esophageal mucosa of opossums. l l So far there has been no report of SEM study of Barrett's esophageal mucosa. The present report describes the SEM of normal esophageal and gastric mucosa and compares the findings with the patterns seen in Barrett's esophagus. MATERIALS AND METHODS Esophagogastroscopy (Olympus GIF-D3) in 2 patients referred to the gastroenterology clinic with nonspecific gastrointestinal complaints, whose upper gastrointestinal radiographs were unremarkable, revealed normal esophageal and gastric mucosa. Specimens were obtained with the standard biopsy forceps. the gastric specimens were taken from the body of the stomach. The esophageal specimens were taken 6 cm above the lower esophageal sphincter. The same procedure was undertaken in 3 patients whose diagnosis of Barrett's esophagus was well established. 6 All the specimens were studied by light microscopy as well as by SEM. Biopsy specimens for SEM were fixed by immersion in Karnovsky's fixative for 24 hours at 4°C. After fixation the
specimens were washed 3 times for 30 minutes at room temperature with 0.1 M Sorenson's buffer. Dehydration was carried out at room temperature by means of 3Dminute washes using a graded series of ethanol (50, 70, 80, 95, and 100%). The absolute (100%) ethanol wash was repeated 3 times. The specimens were then transferred from the last 100% ethanol to wire baskets and placed into a Critical Point Dryer (PElCO Model H). After completion of the critical point cycle, the specimens were m<.>unted on an SEM stub with conductive cement and coated with palladium-gold. Specimens were examined using a IEOl looB instrument equipped with a scanning microscope attachment. RESULTS On SEM the normal esophageal mucosa consisted of flat polygonal epithelial cells and the whole mucosa formed multiple transversely oriented microplicae (Figure 1A). The luminal aspect of the normal esophageal mucosa contained no openings or pits as does the stomach (Figure 18). Our observations of the structure of gastric mucosa conformed with previous descriptions. 2 . 12 The mucosa contained gastric pits or openings, spilling mucus granules, and the surface was mottled (Figure 18). Samples of gastric mucosa from patients with Barrett's esophagus have the same morphologic appearance as those of patients without the disease. The luminal aspect of Barrett's esophagus (Figure 1C) bore no resemblance to a comparable area of the normal esophagus of Figure lA. The surface of Barrett's esophagus was shaggy, with none of the regular and uniform features seen in normal esophageal mucosa. In specimens from a patient with the specialized intestinal type Barrett's epithelium,a the mucosa was covered with numerous microvilli although there were areas denuded of microvilli. Inter-
From the Department of Gastroenterology, Monroe Community Hospital, University of Rochester, School of Medicine and Dentistry, Rochester, New York. Reprint requests: )agdish C. Mangla, MD, Monroe Community Hospital, 43S East Henrietta Road, Rochester, New York 14603. 92
GASTROINTESTINAL ENDOSCOPY
spersed between the microvilli were gastric pit-like openings covered with cellular debris (Figure 10). The microvilli, gastric pit-like openings, and denuded areas were more clearly seen by higher magnification (Figure 1E). In a third patient, also with the specialized type of Barrett's epithelium, the gastric pit-like structures were surrounded by long filamentous structures (Figure 1F).
COMMENTS Examination of conventional sections of the Barrett's esophageal mucosa by light microscopy is adequate for a gross interpretation of its characteristics, but SEM delineates further details of this abnormal mucosa. By
SEM the structure of Barrett's esophagus bears a superficial resemblance to that of normal gastric epithelium. The presence of microvilli is interpreted as a feature of intestinalization and indicates that the mucosa is of the specialized variety of Barrett's esophagus. s The most consistent finding by SEM in normal esophageal mucosa is the presence of prominent surface microridges and regularly lined transverse folds; it contains no openings or pits. In contrast, Barrett's mucosa is devoid of microplicae, denuded, and without any regular structure. A similarity to stomach mucosa is suggested by the presence of gastric pit-like structures, but Barrett's mucosa
Figure 1. A, Mucosal surface of normal human esophagus; the mucosa is regular with prominent delicate transverse folds interspersed by ridges and is finely reticulated; there are no openings or pit-like structures (X 4lJ(X)). B, Normal stomach; the mucosa has many regular gastric pits spilling mucus granules; the columnar cells form a mosaic of poorly defined whorls around the gastric pits (X 224). C, Mucosa in a patient with Barrett's esophagus is shaggy with cellular degeneration; there is no uniformity as seen in A; there are irregular gastric pitlike structures (arrow) covered with cell debris (X 48(0). D, Mucosa in another patient with Barrett's esophagus, again showing irregular mucosa without any regular ridges or folds as seen in A; the mucosa gives a superficial resemblance to gastric mucosa; the gastric pit-like structures are also shaggy (arrows) and covered by cellular debris (X 4lJ(X)). E, On higher magnification of D, this mucosa is covered by microvilli (intestinal type Barrett's mucosa) with irregular gastric pit-like structures; there are regions of focal cellular degeneration and denudation lacking microvilli (X 64(0). F, In the third patient with specialized Barrett's epithelium, the gastric pit-like structure is surrounded by long filamentous structures, the rest of the features being the same as in E. VOLUME 25, NO. 3, 1979
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lacks the fine regular structure of normal gastric mucosa. The specialized intestinal type of Barrett's mucosa exhibits microvilli while still containing pit-like structures. Our SEM observations confirm that Barrett's esophageal mucosa is morphologically distinct when compared with normal gastric or esophageal mucosa. It is conceived that the shaggy, denuded, irregular configuration of Barrett's esophageal mucosa may render it liable to ulceration, bleeding, stricture, and neoplasia.
ACKNOWLEDGMENT The authors acknowledge with thanks the expert technical assistance of Ms. Patricia Santillo.
REFERENCES 1. BARRETT NR: Chronic peptic ulcer of the oesophagus. Br 1 Surg 38:175, 1950 2. ALLISON PR: Peptic ulcer of the oesophagus. Thorax 3:20, 1948 3. WOLF BS, MARSHAK RH, SOM ML, WINKELSTEIN A: Peptic esophagitis, peptic ulcer of the esophagus and marginal esophagogastric ulceration. Gastroenterology 29:744, 1955
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4. SOM ML, WOLF BS: Peptic ulcer of the esophagus and esophagitis in gastric-lined esophagus. lAMA 162:641, 1956 5. LAW SW, SHEEHAN EE: Benign esophageal stricture and the lower esophagus lined by columnar epithelium: Report of two cases. Chest 48:214, 1965 6. MANGLA lC, DESBAILLETS L, SCHENK EA, GUARASCI G, TURNER MD: Pepsin secretion, pepsinogen, and gastrin in "Barrett's esophagus." Gastroenterology 70:669, 1976 7. NAEF AP, SAVARY M, OZZELLO L: Columnar-lined lower esophagus: an acquired lesion with malignant predisposition. 1 Thor Cardiovas Surg 70:826, 1975 8. PAULL A, TRIER], DALTON D, CAMP RC, LOEB P, GOYAL RK: The histologic spectrum of Barrett's esophagus. N Eng 1 Med 295: 476, 1976 9. ALEXANDER IGS, ATKINS AM: Intracellular relationships at epithelial surfaces as seen by scanning electron microscopy. 1 Anat (London) 110:493, 1971 10. CARR KE, DUNN jS, TONER PG: Scanning electron microscopy of the alimentary tract. Scot Moo 1 19:211, 1974 11. ACKERMAN L, PIROS ], DE CARLE D, CHRISTENSEN J: A scanning electron microscopic study of esophageal mucosa. Proceedings of the Workshop on Advances in Biomedical Applications of the SEM. ITT Research Institute, Chicago, 1976 12. FALLAH E, SCHUMAN BM, WATSON IHL, GOODWIN J: Scanning electron microscopy of gastroscopic biopsies. Gastrointestinal Endoscopy 22:137, 1976
GASTROINTESTINAL ENDOSCOPY
Scanning electron microscopy of Barrett's esophageal mucosa Jagdish c. Mangla, MD Chung-Seng Lee, MD Rochester, New York
The morphologic features of Barrett's esophagus as depicted by scanning electron micrography are compared with those of normal esophageal and normal gastric mucosa. The authors conclude that the shaggy, denuded, irregular configuration of Barrett's esophageal mucosa may render it liable to ulceration, bleeding, stricture, and neoplasm.
The normal adult human esophagus is lined by stratified squamous epithelium. In Barrett's esophagus the normal stratified squamous epithelium is replaced by columnar epithelium. First described by N. R. Barrett,l this condition was considered as an esoteric and rare pathologic entity, but lately it is being reported frequently. The mucosa of Barrett's esophagus is prone to bleeding, ulceration, inflammation, and stricture formation. 2 - 6 It has become of increasing concern because supervening adenocarcinoma has been reported in as many as 8.5% of cases.? The histologic spectrum of Barrett's esophagus has been well described. B • a There are few reports of scanning electron microscopy (SEM) of normal esophagus. 9 - 11 One report describes the findings in 2 normal human volunteers and compares these findings to the esophageal mucosa of opossums. l l So far there has been no report of SEM study of Barrett's esophageal mucosa. The present report describes the SEM of normal esophageal and gastric mucosa and compares the findings with the patterns seen in Barrett's esophagus. MATERIALS AND METHODS Esophagogastroscopy (Olympus GIF-D3) in 2 patients referred to the gastroenterology clinic with nonspecific gastrointestinal complaints, whose upper gastrointestinal radiographs were unremarkable, revealed normal esophageal and gastric mucosa. Specimens were obtained with the standard biopsy forceps. the gastric specimens were taken from the body of the stomach. The esophageal specimens were taken 6 cm above the lower esophageal sphincter. The same procedure was undertaken in 3 patients whose diagnosis of Barrett's esophagus was well established. 6 All the specimens were studied by light microscopy as well as by SEM. Biopsy specimens for SEM were fixed by immersion in Karnovsky's fixative for 24 hours at 4°C. After fixation the
specimens were washed 3 times for 30 minutes at room temperature with 0.1 M Sorenson's buffer. Dehydration was carried out at room temperature by means of 3Dminute washes using a graded series of ethanol (50, 70, 80, 95, and 100%). The absolute (100%) ethanol wash was repeated 3 times. The specimens were then transferred from the last 100% ethanol to wire baskets and placed into a Critical Point Dryer (PElCO Model H). After completion of the critical point cycle, the specimens were m<.>unted on an SEM stub with conductive cement and coated with palladium-gold. Specimens were examined using a IEOl looB instrument equipped with a scanning microscope attachment. RESULTS On SEM the normal esophageal mucosa consisted of flat polygonal epithelial cells and the whole mucosa formed multiple transversely oriented microplicae (Figure 1A). The luminal aspect of the normal esophageal mucosa contained no openings or pits as does the stomach (Figure 18). Our observations of the structure of gastric mucosa conformed with previous descriptions. 2 . 12 The mucosa contained gastric pits or openings, spilling mucus granules, and the surface was mottled (Figure 18). Samples of gastric mucosa from patients with Barrett's esophagus have the same morphologic appearance as those of patients without the disease. The luminal aspect of Barrett's esophagus (Figure 1C) bore no resemblance to a comparable area of the normal esophagus of Figure lA. The surface of Barrett's esophagus was shaggy, with none of the regular and uniform features seen in normal esophageal mucosa. In specimens from a patient with the specialized intestinal type Barrett's epithelium,a the mucosa was covered with numerous microvilli although there were areas denuded of microvilli. Inter-
From the Department of Gastroenterology, Monroe Community Hospital, University of Rochester, School of Medicine and Dentistry, Rochester, New York. Reprint requests: )agdish C. Mangla, MD, Monroe Community Hospital, 43S East Henrietta Road, Rochester, New York 14603. 92
GASTROINTESTINAL ENDOSCOPY
spersed between the microvilli were gastric pit-like openings covered with cellular debris (Figure 10). The microvilli, gastric pit-like openings, and denuded areas were more clearly seen by higher magnification (Figure 1E). In a third patient, also with the specialized type of Barrett's epithelium, the gastric pit-like structures were surrounded by long filamentous structures (Figure 1F).
COMMENTS Examination of conventional sections of the Barrett's esophageal mucosa by light microscopy is adequate for a gross interpretation of its characteristics, but SEM delineates further details of this abnormal mucosa. By
SEM the structure of Barrett's esophagus bears a superficial resemblance to that of normal gastric epithelium. The presence of microvilli is interpreted as a feature of intestinalization and indicates that the mucosa is of the specialized variety of Barrett's esophagus. s The most consistent finding by SEM in normal esophageal mucosa is the presence of prominent surface microridges and regularly lined transverse folds; it contains no openings or pits. In contrast, Barrett's mucosa is devoid of microplicae, denuded, and without any regular structure. A similarity to stomach mucosa is suggested by the presence of gastric pit-like structures, but Barrett's mucosa
Figure 1. A, Mucosal surface of normal human esophagus; the mucosa is regular with prominent delicate transverse folds interspersed by ridges and is finely reticulated; there are no openings or pit-like structures (X 4lJ(X)). B, Normal stomach; the mucosa has many regular gastric pits spilling mucus granules; the columnar cells form a mosaic of poorly defined whorls around the gastric pits (X 224). C, Mucosa in a patient with Barrett's esophagus is shaggy with cellular degeneration; there is no uniformity as seen in A; there are irregular gastric pitlike structures (arrow) covered with cell debris (X 48(0). D, Mucosa in another patient with Barrett's esophagus, again showing irregular mucosa without any regular ridges or folds as seen in A; the mucosa gives a superficial resemblance to gastric mucosa; the gastric pit-like structures are also shaggy (arrows) and covered by cellular debris (X 4lJ(X)). E, On higher magnification of D, this mucosa is covered by microvilli (intestinal type Barrett's mucosa) with irregular gastric pit-like structures; there are regions of focal cellular degeneration and denudation lacking microvilli (X 64(0). F, In the third patient with specialized Barrett's epithelium, the gastric pit-like structure is surrounded by long filamentous structures, the rest of the features being the same as in E. VOLUME 25, NO. 3, 1979
93
lacks the fine regular structure of normal gastric mucosa. The specialized intestinal type of Barrett's mucosa exhibits microvilli while still containing pit-like structures. Our SEM observations confirm that Barrett's esophageal mucosa is morphologically distinct when compared with normal gastric or esophageal mucosa. It is conceived that the shaggy, denuded, irregular configuration of Barrett's esophageal mucosa may render it liable to ulceration, bleeding, stricture, and neoplasia.
ACKNOWLEDGMENT The authors acknowledge with thanks the expert technical assistance of Ms. Patricia Santillo.
REFERENCES 1. BARRETT NR: Chronic peptic ulcer of the oesophagus. Br 1 Surg 38:175, 1950 2. ALLISON PR: Peptic ulcer of the oesophagus. Thorax 3:20, 1948 3. WOLF BS, MARSHAK RH, SOM ML, WINKELSTEIN A: Peptic esophagitis, peptic ulcer of the esophagus and marginal esophagogastric ulceration. Gastroenterology 29:744, 1955
94
4. SOM ML, WOLF BS: Peptic ulcer of the esophagus and esophagitis in gastric-lined esophagus. lAMA 162:641, 1956 5. LAW SW, SHEEHAN EE: Benign esophageal stricture and the lower esophagus lined by columnar epithelium: Report of two cases. Chest 48:214, 1965 6. MANGLA lC, DESBAILLETS L, SCHENK EA, GUARASCI G, TURNER MD: Pepsin secretion, pepsinogen, and gastrin in "Barrett's esophagus." Gastroenterology 70:669, 1976 7. NAEF AP, SAVARY M, OZZELLO L: Columnar-lined lower esophagus: an acquired lesion with malignant predisposition. 1 Thor Cardiovas Surg 70:826, 1975 8. PAULL A, TRIER], DALTON D, CAMP RC, LOEB P, GOYAL RK: The histologic spectrum of Barrett's esophagus. N Eng 1 Med 295: 476, 1976 9. ALEXANDER IGS, ATKINS AM: Intracellular relationships at epithelial surfaces as seen by scanning electron microscopy. 1 Anat (London) 110:493, 1971 10. CARR KE, DUNN jS, TONER PG: Scanning electron microscopy of the alimentary tract. Scot Moo 1 19:211, 1974 11. ACKERMAN L, PIROS ], DE CARLE D, CHRISTENSEN J: A scanning electron microscopic study of esophageal mucosa. Proceedings of the Workshop on Advances in Biomedical Applications of the SEM. ITT Research Institute, Chicago, 1976 12. FALLAH E, SCHUMAN BM, WATSON IHL, GOODWIN J: Scanning electron microscopy of gastroscopic biopsies. Gastrointestinal Endoscopy 22:137, 1976
GASTROINTESTINAL ENDOSCOPY