Endoscopy 1 (1979) 36-42
Diminutive Colonic Polyps Clinical Significance and Management S. Granqvist, N. Gabrielsson, P. Sundelin
Summary
Of 300 diminutive polyps .(up to 5 mm) found at colonoscopy, 114 were neoplastic (37 per cent) and
thus possible precursors of carcinoma. This suggests that all colonic polyps, regardless of size, should if possible be extirpated or coagulated. As polyps of this small size often escape detection roentgenologically,
especially
by
conventional
technique, colonoscopy should be extended to involve the entire colon. This is because diminutive polyps, especially of neoplastic type, are common also in the proximal part of the colon.
Key-Words: Diminutive colonic polyps, radiology, endoscopy, histopathology, management.
In several studies carcinoma has been found
in more than every tenth colonic polyp exceeding 1 cm in size (8, 9), and diagnosis and extirpation of such polyps is therefore
considered very important. However, the management of very small colonic polyps 5 mm or less is more doubtful. Polyps of
this size were earlier only rarely found by roentgenography. With improved roentgenological technique, however, small polyps can be diagnosed to a greater extent (19, 20). By means of colonoscopy it is now possible to detect polyps down to millimetre size
Kleine Kolonpolypen ihre klinische Bedeutung und Behandlung Von 300 bei der Koloskopie festgestellten kleinen Polypen (bis 5 mm) waren 114 neoplastisch ( = 37%) und daher mögliche Kolonkarzinomvorläufer. Daraus wird der Vorschlag abgeleitet, möglichst alle Kolonpolypen ungeachtet ihrer Gröge zu exstirpieren bzw. zu koagulieren. Da Polypen von derart kleinen Abmessungen röntgenologisch oft nicht nachweisbar sind, insbesondere mit den herkömmlichen Aufnahmetechniken, sollte die Kolo-
skopie auf den gesamten Dickdarm ausgedehnt werden, weil kleine Polypen, insbesondere neoplastischer Art, auch häufig im proximalen Teil des Kolon auftreten.
plastic type (3, 11) and there is no evidence that such polyps can develop into carcinoma (10, 14). On the other hand, a rectoscopic study of 1,000 polyps up to 5 mm showed 86 per cent to be neoplastic and dysplasia occurred in 55 per cent of the polyps (16). Also in an autopsy material two-thirds of the polyps under 5 mm were of the adenomatous type (1).
The aim of the present investigation was to ascertain the importance of diminutive polyps seen in
colonoscopy, by means of his-
topathologic classification. Special attention
throughout the colon. The question of the
was paid to their distribution in the large
management of these diminutive polyps has therefore come up for discussion in recent years. From the literature it is apparent that carcinoma is extremely rare in such small polyps (9, 16). On the other hand, reports are contradictory concerning the proportion of diminutive polyps which are neoplastic and accordingly may progress to carcinoma. It has
bowel as the literature on colonic polyps gives
no definite guidance in this respect. In most materials polyps are found to be situated predominantly distally (9, 20), in others they are reported to be uniformly distributed through-
out the colon
(4,
5). The proportion of
been stated that 90 per cent of all colonic
diminutive polyps observed prior to colonoscopy by means of conventional and of double contrast roentgenography has also been
polyps up to 3-4 mm in size are of the meta-
calculated.
0013-726 X/79
1300-0036
$ 02.00
CD 1979
Georg Thieme Publishers
Downloaded by: National University of Singapore. Copyrighted material.
Departments of Diagnostic Radiology and Pathology, Huddinge, Sweden
Diminutive Colonic Polyps
x545
Tubular adenoma. Hematoxylin and eosin,
Material and Method In our study, the material consisted of 300 diminutive colonic polyps (up to 5 mm) in the
colon of 114 patients 71 men and 43 women. The patients examined were aged between 30 and 83 years, mean age 63 years. Polyps in patients with inflammatory intesti-
nal disease were not included in the study. Colonoscopy was performed with a long colonoscope (Olympus) and the entire colon was examined in 84 per cent of the cases. The
size of polyps which were not removed was assessed by comparison with the diameter of the biopsy forceps (2.5 mm). The average size of all polyps was 3.2 mm. Fifty-eight polyps were examined histologically in their entirety after endoscopic polypectomy; from the remainder one or more biopsies were
Fig. 2
x545
Metaplastic polyp. Hematoxylin and eosin,
Histological classification of 300 diminutive polyps Table 1
Neoplastic (adenomatous, villous, adenovillous) Slight dysplasia 71 Moderate dysplasia 39 I 111 Severe dysplasia 1
Non- neoplastic Metaplastic Inflammatory Fibrous tissue Normal mucosa
117 } 20 6
189
46
degree of epithelial dysplasia (Fig. 1). The
simulate neoplasia, is the metaplastic polyp (Fig. 2). In typical cases, however, the metaplastic polyp is easily identified. It is characterized by a villous structure. Its epithelial cells have a large, slightly eosinophilic cytoplasm, and lack nuclear dysplasia (14). The cases in which the biopsy material was too scanty for detailed assessment were not included in the series. Roentgenography was
only kind of non-neoplastic polyp which may
performed within 6 months (average
examined. The polyps were then subdivided into neoplastic and non-neoplastic ones. The neoplastic polyps, which are of tubular, vill-
ous or mixed type, always possess some
1.6
Downloaded by: National University of Singapore. Copyrighted material.
Fig. 1
37
38
S. Granqmst, N. Gabrielsson, P. Sonde/in
Table 2
Proportion of neoplastic diminutive polyps in groups divided according to various characteristics of polyps and patients
size
Proportion of neoplastic polyps
in mm
in per cent
Statistically significant difference
215 85 273 27
2.6 4.7
27
p
61
34 67
p < 0.001
4.6
113 187
3.3 3.2
50 29
p < 0.0005
103 197
3.2 3.3
26 43
p=
0.005
106 194
3.2 3.2
45 32
p
60 years Women Men
Concurrent of earlier neoplasia of the colon > 5 mm Carcinoma Benign polyp No tumour
3.1
171
49
Diminutive Colonic Polyps Clinical Significance and Management S. Granqvist, N. Gabrielsson, P. Sundelin
Summary
Of 300 diminutive polyps .(up to 5 mm) found at colonoscopy, 114 were neoplastic (37 per cent) and
thus possible precursors of carcinoma. This suggests that all colonic polyps, regardless of size, should if possible be extirpated or coagulated. As polyps of this small size often escape detection roentgenologically,
especially
by
conventional
technique, colonoscopy should be extended to involve the entire colon. This is because diminutive polyps, especially of neoplastic type, are common also in the proximal part of the colon.
Key-Words: Diminutive colonic polyps, radiology, endoscopy, histopathology, management.
In several studies carcinoma has been found
in more than every tenth colonic polyp exceeding 1 cm in size (8, 9), and diagnosis and extirpation of such polyps is therefore
considered very important. However, the management of very small colonic polyps 5 mm or less is more doubtful. Polyps of
this size were earlier only rarely found by roentgenography. With improved roentgenological technique, however, small polyps can be diagnosed to a greater extent (19, 20). By means of colonoscopy it is now possible to detect polyps down to millimetre size
Kleine Kolonpolypen ihre klinische Bedeutung und Behandlung Von 300 bei der Koloskopie festgestellten kleinen Polypen (bis 5 mm) waren 114 neoplastisch ( = 37%) und daher mögliche Kolonkarzinomvorläufer. Daraus wird der Vorschlag abgeleitet, möglichst alle Kolonpolypen ungeachtet ihrer Gröge zu exstirpieren bzw. zu koagulieren. Da Polypen von derart kleinen Abmessungen röntgenologisch oft nicht nachweisbar sind, insbesondere mit den herkömmlichen Aufnahmetechniken, sollte die Kolo-
skopie auf den gesamten Dickdarm ausgedehnt werden, weil kleine Polypen, insbesondere neoplastischer Art, auch häufig im proximalen Teil des Kolon auftreten.
plastic type (3, 11) and there is no evidence that such polyps can develop into carcinoma (10, 14). On the other hand, a rectoscopic study of 1,000 polyps up to 5 mm showed 86 per cent to be neoplastic and dysplasia occurred in 55 per cent of the polyps (16). Also in an autopsy material two-thirds of the polyps under 5 mm were of the adenomatous type (1).
The aim of the present investigation was to ascertain the importance of diminutive polyps seen in
colonoscopy, by means of his-
topathologic classification. Special attention
throughout the colon. The question of the
was paid to their distribution in the large
management of these diminutive polyps has therefore come up for discussion in recent years. From the literature it is apparent that carcinoma is extremely rare in such small polyps (9, 16). On the other hand, reports are contradictory concerning the proportion of diminutive polyps which are neoplastic and accordingly may progress to carcinoma. It has
bowel as the literature on colonic polyps gives
no definite guidance in this respect. In most materials polyps are found to be situated predominantly distally (9, 20), in others they are reported to be uniformly distributed through-
out the colon
(4,
5). The proportion of
been stated that 90 per cent of all colonic
diminutive polyps observed prior to colonoscopy by means of conventional and of double contrast roentgenography has also been
polyps up to 3-4 mm in size are of the meta-
calculated.
0013-726 X/79
1300-0036
$ 02.00
CD 1979
Georg Thieme Publishers
Downloaded by: National University of Singapore. Copyrighted material.
Departments of Diagnostic Radiology and Pathology, Huddinge, Sweden
Diminutive Colonic Polyps
x545
Tubular adenoma. Hematoxylin and eosin,
Material and Method In our study, the material consisted of 300 diminutive colonic polyps (up to 5 mm) in the
colon of 114 patients 71 men and 43 women. The patients examined were aged between 30 and 83 years, mean age 63 years. Polyps in patients with inflammatory intesti-
nal disease were not included in the study. Colonoscopy was performed with a long colonoscope (Olympus) and the entire colon was examined in 84 per cent of the cases. The
size of polyps which were not removed was assessed by comparison with the diameter of the biopsy forceps (2.5 mm). The average size of all polyps was 3.2 mm. Fifty-eight polyps were examined histologically in their entirety after endoscopic polypectomy; from the remainder one or more biopsies were
Fig. 2
x545
Metaplastic polyp. Hematoxylin and eosin,
Histological classification of 300 diminutive polyps Table 1
Neoplastic (adenomatous, villous, adenovillous) Slight dysplasia 71 Moderate dysplasia 39 I 111 Severe dysplasia 1
Non- neoplastic Metaplastic Inflammatory Fibrous tissue Normal mucosa
117 } 20 6
189
46
degree of epithelial dysplasia (Fig. 1). The
simulate neoplasia, is the metaplastic polyp (Fig. 2). In typical cases, however, the metaplastic polyp is easily identified. It is characterized by a villous structure. Its epithelial cells have a large, slightly eosinophilic cytoplasm, and lack nuclear dysplasia (14). The cases in which the biopsy material was too scanty for detailed assessment were not included in the series. Roentgenography was
only kind of non-neoplastic polyp which may
performed within 6 months (average
examined. The polyps were then subdivided into neoplastic and non-neoplastic ones. The neoplastic polyps, which are of tubular, vill-
ous or mixed type, always possess some
1.6
Downloaded by: National University of Singapore. Copyrighted material.
Fig. 1
37
38
S. Granqmst, N. Gabrielsson, P. Sonde/in
Table 2
Proportion of neoplastic diminutive polyps in groups divided according to various characteristics of polyps and patients
size
Proportion of neoplastic polyps
in mm
in per cent
Statistically significant difference
215 85 273 27
2.6 4.7
27
p
61
34 67
p < 0.001
4.6
113 187
3.3 3.2
50 29
p < 0.0005
103 197
3.2 3.3
26 43
p=
0.005
106 194
3.2 3.2
45 32
p
60 years Women Men
Concurrent of earlier neoplasia of the colon > 5 mm Carcinoma Benign polyp No tumour
3.1
171
49
