Diagnostic accuracy of pit pattern and vascular pattern in colorectal lesions

Digestive Disease Center, Showa University Northern Yokohama Hospital Department of Pathology ♯

Yoshiki Wada, Shin-ei Kudo, Hiroshi Kashida, Masashi Misawa, Takemasa Hayashi, Toshihisa Hosoya, Kunihiko Wakamura,

Nobunao Ikehara, Shigeharu Hamatani＃

Background •  Pit pattern analysis has been reported as useful for predicting the colorectal lesion’s histological nature. •  Recently a new method of image-enhanced endoscopy called narrow band imaging (NBI) has been developed. The benefits of NBI over chromoendoscopy are that it is easier and time-saving.

Aim •  The aim of this prospective study is to compare the usefulness of magnifying narrow band imaging (NBI) and magnifying chromoendoscopy in the diagnosis of colorectal lesions.

Subjects

•  3380 lesions (106 hyperplastic polyps, 3056 adenomas and 218 invasive cancers limited to submucosal layer) which were observed by magnifying scope with NBI and magnifying chromoendoscopy and treated endoscopically or surgically from January 2006 to June 2009.

•  The scopes were CF-H260AZI (up to x 80). •  The diagnosis of NBI and pit pattern was made by endoscopists who were blinded to the final pathological diagnosis. •  The pit patterns were classified into I, II, III, IV, VI and VN according to Kudo’s classification. •  VI pit pattern was divided into VI low-grade and VI high-grade. Our definitions for VI high-grade pit pattern were rough margin and narrowed lumen.

Methods

•  We classified colonic microvascular pattern into six; normal, faint, network, dense, irregular and sparse. •  Faint pattern was usually seen in hyperplastic polyps. Network and dense patterns were frequently recognized in benign adenomas. •  Irregular pattern was characteristic for protruded or flat cancers, and sparse pattern was predictive for depressed cancers.

Kudo S, et al. Gastrointest Endosc 1996; 44: 8-14

Surgical Specimen EMR Specimen

carcinoma

muscularis mucosa

sm scanty

sm massive submucosa

submucosa

resection margin muscularis propria

sm1

sm2

sm3

Tsuruta O, Toyonaga A, Ikeda H et al. Int J Oncology 1997; 10: 1003-08

Classification of the degree of submucosal invasion

Vascular Pattern Classification

Normal pattern Faint pattern Network pattern

Dense pattern Irregular pattern Sparse pattern Wada Y, Kudo S, Kashida H et al. Gastrointest Endosc 2009; 70: 522-31

Pit Pattern Classification (Kudo’s Classification)

I II IIIs

IIIL IV VI VN

Kudo S et al. Endoscopy 2001; 33: 367-373

rough margin narrowed lumen

Definitions for VI high-grade pit pattern

network

dense

faint

Comparison between vascular pattern and pathological diagnosis

hyp* adenoma

vascular pattern

total pathological diagnosis

106 3056 total 3380

89

2426

531

47**

17

irregular

sparse

SMm

40

12

65

87

7

5

164

111

108

544

2481

136

* hyperplastic polyp

SMs

54

33

6

6

9

** 31 lesions were sessile serrated adenomas.

pathological diagnosis

hyp neoplasia

faint

network / dense irregular / sparse

47**

106 3274

17 3227

89

3380

136

total

total

sensitivity 84.0%, specificity 98.6%, accuracy 98.1%

3244

vascular pattern

Differential diagnosis between hyperplastic polyp and neoplasia by vascular pattern

** 31 lesions were sessile serrated adenomas.

pathological diagnosis

SMm adenoma / SMs

network / dense / faint

irregular / sparse 67

164 3110

12 3043

152

3274

219

total

total

Vascular patterns of submucosally invasive cancers

sensitivity 92.7%, specificity 97.8%, accuracy 97.6%

3055

vascular pattern

1987 IIIL

IIIs II

Comparison between pit pattern and pathological diagnosis

hyp adenoma pit pattern total

pathological diagnosis

total

96

1978

35

20

9 IV

VI low-grade

SMm

788

222

6

16

807

273

35 116

VI high-grade 13 91 111 VN 51 51

SMs

12

35 7

1

106 3056 3380 164 54

pathological diagnosis

hyp neoplasia

II

III / IV / VI / VN

20

106 3294

10 3274

96

3380

116

total

total

sensitivity 90.6%, specificity 99.4%, accuracy 99.1%

3264

pit pattern

Differential diagnosis between hyperplastic polyp and neoplasia by pit pattern

pathological diagnosis

SMm

VI low-grade / IV / III /II

VN / VI high-grade 20

164 3110

22 3090

142

3274

162

total

total

Pit patterns of submucosally invasive cancers

sensitivity 86.6%, specificity 99.4%, accuracy 98.7%

3112

pit pattern adenoma / SMs

Rectosigmoid colon, Is, 9mm　 Case 1

irregular pattern

VI high-grade

Adenocarcinoma (tub1) with adenoma, sm2 (pSM 1500µm), ly1, v0

Rectosigmoid colon, IIa+IIc, 10mm　 Case 2

sparse pattern

VI high-grade

Adenocarcinoma (tub2 > tub1), sm3 (pSM 3250µm), ly1, v2, pN1, H1

Summary

•  Both NBI and chromoendoscopy can be useful tools for distinguishing between neoplastic and non-neoplastic lesions. •  In the diagnosis of submucosal cancer, pit pattern diagnosis was a little superior to vascular pattern diagnosis.

Conclusion

•  It is desirable to perform not only NBI but also chromoendoscopy for distinguishing between SMm and SMs and determining treatment selection, endoscopic or surgical.

Diagnostic accuracy of pit pattern and vascular pattern in colorectal lesions

Digestive Disease Center, Showa University Northern Yokohama Hospital Department of Pathology #

Yoshiki Wada, Shin-ei Kudo, Hiroshi Kashida, Masashi Misawa, Takemasa Hayashi Toshihisa Hosoya, Kunihiko Wakamura, Nobunao Ikehara, Shigeharu Hamatani＃