위암의 병기판정에 있어서 내시경 초음파검사의 유용성

Abstract

[한글]

우리나라에서 가장 흔한 암종으로 성인 남자와 여자에서 암에 의한 사망중 각각 1, 2위를 차지하고 있는 위암의 예후는 진단 당시의 병기가 가장 풍요하다. 1980년부터 개발되어 널리 보급되고 있는 내시경초음파검사(Endoscopic Ultrasonography: 이하 EUS)는 복부

초음파검사가 가지는 초음파의 투과장애요인을 해결하고, 7.5 내지 12 MHz의 주파수를 이용하므로 늘은 해상도의 초음파영상을 얻을 수 있는 검사법으로 부각되고 있다. 최근 EUS가 위암의 심달도 진단과 임파절 전이의 판정에 정확도가 높다는 보고들이 이어지고 있으나, 그 정도는 보고자마다 상이하다. 이애 연구자는 위암의 심달도 및 임파절전이애 있어서 EUS의 정확도를 알아보고, 이러한 정확도에 영향을 줄 수 있는 암병변의 특성들(진행정도, 형태, 위치, 크기, 병리분류, 분화도, 궤양형성 유무등)과 오진된 경우에 병리조직학적 원인을 조사하고자 하였다. EUS를 시행하고 수술을 받았으며 절재된 조직의 병리소

견으로 침윤정도를 알 수 있었던 116예(조기위암 30에, 진행위암 86예)를 대상으로 하였으며, Olympus사의 sector형 초음파내시경(GF-UM3)과 관측장치(EU-M3)로서. 주파수 7.5 MHz의 탐촉자를 사용하였다. 풍선밀갈법(balloon method)이나 탈기수층만법(deaerated wat

er filled method)으로 시행하여 위암의 심달도, 주변임파절 밋 주위장기에 전이 유무등을 판정하였다. EUS에 의한 위암의 심달도 판정은 Yasuda 등(1986)의 분류를 기준으로 하였다.

EUS에 의한 심달도 진단을 수술후 병리조직의 결과와 비교하였는데 점막층암이 15예중 9예(60.07), 점막하층암이 15예중 4예(26.77). 고유근층암이 26예중 11예(42.377), 장막하층 이상을 침범한 암이 60예중 54예(90.07)에서 일치하여 전채 116예중 78예로 67.2%의

진단정확도를 나타내었다. 대상 중예를 조기암과 진행암으로 감별진단할 경우, 그 정확도는 조기암 56.7%(17/30), 진행암93%(80/86)로 전체적으로 83.6%(97/116)의 감별진단 정확도를 나타냈다. Ⅱc+Ⅲ형 Ⅲ형 조기위암은 심달도의 진단정확도는 0%(0/8에)였으며, Borrmann Ⅳ형 진행암은 90.9%(10/11에)의 진단정확도를 보였다. 궤양을 동반한 경우 67.5%(54/80), 궤양을 동반하지 앉은 경우 69.4%(25/36에)외 진단정확도를 나타내었다. 조직형별, 조직분화도별 심달도의 진단정착도는 차이가 없었다. 진행위암이 체하부에 위치한 경우 93.7%(14/15에), 소만부에 위치한 겅우에는 8l%(36/44에)의 진단정확도를 보였다. 총 116예중 38예에서 심달도의 진단이 오진되었으며. 과대평가된 경우가 28예었고 과소평가

된 경우가 10예었다. 과대평가된 경우 궤양저부에 섬유화가 등반된 예가 15예로 가장 많았으며, 종괴의 압박으로 주위 조직층 구조가 �曇팁�것이 암의 침윤으로 오인된 경우가 5예, 암주변 염증세포들의 침윤에 희한 경우가 1예등이었고, 원인을 알 수 없는 경우도 7

예었다. 과소평가된 경우 9에가 EUS상에 발견되지 않았던 암세포의 미소침윤이었고,1에어서는 원인을 찾을 수 없었다. 임파절전이 유무만을 판정한 결과 N^^0 는78.9%(41/52에)에서 임파절전이가 없는 것으로 진단하였고, N^^1 은 65.2%(15/23에)어서 임파절전이 양성

으로 진단하였으며. N^^2 의 경우는 85.4%(35/41에)어서 임파절전이 양성으로 진단하였다. 층 12에의 원격전이중 2에에서만 원격전이가 있는 것으로 진단하였는데 이들 2에는 간좌엽의 전이와 악성복수가 있는 경우였다.

위암환자어서 EUS는 심달도 진단에 있어서 유용한 방법으로 이용될 수 있으나 진단정확도를 높이기 위해서는 병리조직학적 변화에 따른 EUS의 초음파상을 토대로 EUS소견을 해석하여야할 것으로 생각된다. 그리고 기존의 영상 진단법과 함께 위암의 병기판정에 보조적인 진단법으로 유용하게 사용될 수 있을 것이다.

Endoscopic ultrasonography(EUS) for staging of the gastric cancer

Sang Bae Chun

Department of Medical Science, The Graduate School, Yonsei University

(Directed by Professors In Suh Park)

The postoperative prognosis of the patients with gastric cancer depends on stage,

defined as the depth of the tumor invasion and extent of lymph node metastasis. In

comparison with the customary endoscope and radiologic imaging techniques,

endoscopic ultrasonography(EUS) provide us with a new tool to assess the upper

gastrointestinal tract, which has the potential to reach region previous1y

inassessible. EUS has been found useful in assesing the depth of invasion of

gastric cancer and the extent of lymph node metastasis. but the accuracy of

diagnosis for the depth of tumor invasion and the extent of lymph node metastasis

are reported so variable as to reporters. EUS was performed in 116 patients with

gastric cancer in order to estimate the depth of tumor invasion on the gastric wall

and the extent of lymph node metastasis. Subsequently all patients underwent

operation, and the depth of tumor invasion and the extent of lymph node metastasis

was confirmed by histologic examination. The instrument which we have employed in

thus study was GF-UM3 and EU-M3(7.5MHz) manufactured by Olympus Company.

1. The diagnostic accuracy in the depth of tumor invasion was 60.O% (9/15 cases)

in the m-cancer, 26.7% (4/15 cases) in the sm-cancer, 42.3%(l1/2 cases) in the

pm-cancer and 90.0% (54/60 cartes) in the cancer above ss-layer, respectively and

the overal1 diagnostic accuracy was 67.2% (78/116 cases), The accuracy in

differentiation between EGC and AGC was 83.6% (97/116 Cases).

2. The diagnostic accuracy in the depth of tumor invasion in EGC type Ⅱc+Ⅲ and

type Ⅲ was O% (O/8 cases).

3. The diagnostic accuracy in the depth of tumor invasion was 67.5%(54/80) in

cases with ulceration and 69.4%(25/36) in cases without ulceration

4. The diagnostic accuracy in the depth of tumor invasion in relation to the

histologic type and differentiation did not show significant difference.

5. The diagnostic accuracy in the depth of tumor invasion was 93.3%(14/15) in the

cases located at the lower body and 81.8%(36/44) at the lesser curvature.

6. The extant of disease in the depth of tumor invasion was overestimated in 28

cases and underestimated in 10 cases. Overestimating was due to ulceration wi th

concomitent fibrosis in 39.5%(15/38) cases, thinned next layers by pressure effect

of tumor mass in 13.2%(5/38) cases, The main cause of underestimation(23.7%; 9/38)

was due to microinvasion into the next layer which was not demonstrated as a change

of structure by EUS

7. Lymph node metastasis was diagnosed as negative in N^^0 cases(78.9%;41/52) and

as positive in N^^1 cases(65.2%;15/23) and N^^2 cases985.4%;35/41), respectively.

8. In the evaluation of all 12 cases with distant metastasis, EUS could diagnose

in only 2 cases which were metastatic cases to the left lobe of the liver and

malignant ascites.

As a result obtained. we could know that EUS image of gastric cancer provided

useful information on the depth of cancer invasion and regional Iymph node

metastasis and that the petritumorous pathologic changes affect on diagnostic

accuracy of EUS in the depth of tumor invasion in gastric cancer.

[영문]

The postoperative prognosis of the patients with gastric cancer depends on stage, defined as the depth of the tumor invasion and extent of lymph node metastasis. In comparison with the customary endoscope and radiologic imaging techniques, endoscopic ultrasonography(EUS) provide us with a new tool to assess the upper gastrointestinal tract, which has the potential to reach region previous1y inassessible. EUS has been found useful in assesing the depth of invasion of gastric cancer and the extent of lymph node metastasis. but the accuracy of diagnosis for the depth of tumor invasion and the extent of lymph node metastasis

are reported so variable as to reporters. EUS was performed in 116 patients with gastric cancer in order to estimate the depth of tumor invasion on the gastric wall and the extent of lymph node metastasis. Subsequently all patients underwent

operation, and the depth of tumor invasion and the extent of lymph node metastasis was confirmed by histologic examination. The instrument which we have employed in thus study was GF-UM3 and EU-M3(7.5MHz) manufactured by Olympus Company.

1. The diagnostic accuracy in the depth of tumor invasion was 60.O% (9/15 cases) in the m-cancer, 26.7% (4/15 cases) in the sm-cancer, 42.3%(l1/2 cases) in the pm-cancer and 90.0% (54/60 cartes) in the cancer above ss-layer, respectively and the overal1 diagnostic accuracy was 67.2% (78/116 cases), The accuracy in differentiation between EGC and AGC was 83.6% (97/116 Cases).

2. The diagnostic accuracy in the depth of tumor invasion in EGC type Ⅱc+Ⅲ and type Ⅲ was O% (O/8 cases).

3. The diagnostic accuracy in the depth of tumor invasion was 67.5%(54/80) in cases with ulceration and 69.4%(25/36) in cases without ulceration

4. The diagnostic accuracy in the depth of tumor invasion in relation to the histologic type and differentiation did not show significant difference.

5. The diagnostic accuracy in the depth of tumor invasion was 93.3%(14/15) in the cases located at the lower body and 81.8%(36/44) at the lesser curvature.

6. The extant of disease in the depth of tumor invasion was overestimated in 28 cases and underestimated in 10 cases. Overestimating was due to ulceration wi th concomitent fibrosis in 39.5%(15/38) cases, thinned next layers by pressure effect

of tumor mass in 13.2%(5/38) cases, The main cause of underestimation(23.7%; 9/38) was due to microinvasion into the next layer which was not demonstrated as a change

of structure by EUS

7. Lymph node metastasis was diagnosed as negative in N^^0 cases(78.9%;41/52) and as positive in N^^1 cases(65.2%;15/23) and N^^2 cases985.4%;35/41), respectively.

8. In the evaluation of all 12 cases with distant metastasis, EUS could diagnose in only 2 cases which were metastatic cases to the left lobe of the liver and malignant ascites.

As a result obtained. we could know that EUS image of gastric cancer provided useful information on the depth of cancer invasion and regional Iymph node metastasis and that the petritumorous pathologic changes affect on diagnostic

accuracy of EUS in the depth of tumor invasion in gastric cancer.