乳癌超音波診断における3次元超音波検査の有用性

Miho Hirano; 平野 美穂; Masumi Hashimoto; 橋本 真澄; Masako Matsuda; 松田 雅子; Tomoyuki Aruga; 有賀 智之; Shinichirou Horiguchi; 堀口慎一郎; Yoshikazu Ozaki; 尾崎 喜一; Taminori Oobayashi; 大林 民典

doi:10.11272/jss.41.386

乳癌超音波診断における3次元超音波検査の有用性Usefulness of 3D-ultrasound in the Breast Cancer Diagnosis

平野美穂¹，橋本真澄¹，松田雅子¹，有賀智之²，堀口慎一郎³，尾崎喜一¹，大林民典⁴Miho Hirano¹, Masumi Hashimoto¹, Masako Matsuda¹, Tomoyuki Aruga², Shinichirou Horiguchi³, Yoshikazu Ozaki¹, Taminori Oobayashi⁴

¹ がん・感染症センター都立駒込病院臨床検査科Departments of Clinical Laboratory, Tokyo Metropolitan Cancer and  Infectious Disease Center Komagome Hospital

² がん・感染症センター都立駒込病院乳腺外科Departments of Mammary Gland Surgery, Tokyo Metropolitan Cancer and  Infectious Disease Center Komagome Hospital

³ がん・感染症センター都立駒込病院病理科Departments of Pathology, Tokyo Metropolitan Cancer and  Infectious Disease Center Komagome Hospital

⁴ 東埼玉総合病院診療部臨床検査科Departments of Clinical Laboratory, Higashi Saitama General Hospital

受付日：2015年6月13日Received: June 13, 2015

受理日：2016年6月12日Accepted: June 12, 2016

発行日：2016年8月1日Published: August 1, 2016

目的：3D超音波（US）による乳癌の腫瘍体積測定の臨床的妥当性，有用性を証明することを目的とした．また，PSC（primary systemic chemotherapy）の治療効果判定法としての3D-USの可能性についても検討した．

対象と方法：対象は2011年4月から2013年8月までに当院にて乳腺超音波検査を施行し，細胞診，針生検または切除生検にて診断が確定された乳腺腫瘍91例91結節．乳腺超音波検査に携っている臨床検査技師8名が高周波リニア型プローブおよび3D型プローブを用いて検査を施行した．検討項目は①トレース断面数の違いによる腫瘍体積計測値，②良性腫瘍と悪性腫瘍の体積測定値，③悪性腫瘍と良性腫瘍の習熟度別体積測定値，④3D-USと摘出標本から算出した体積の乳癌組織型による差，⑤乳癌術前化学療法の効果判定．統計学的検討は①，②はt検定，③はMann–Whitney U検定，④はχ²検定を用い，有意水準5%とした．

結果：①各トレース断面数ごとの体積の差には有意差はみられなかった（p＞0.05）．②悪性腫瘍の変動係数の最頻値は良性腫瘍より有意に高値であった（p＝0.007）．③体積計測の変動係数は，検査習熟前の前期では悪性と良性腫瘍間に有意差がみられた（p＝0.007）が，習熟後の後期では有意差はみられなかった（p＝0.14）．④乳頭腺管癌と硬癌との，3D-USと摘出検体から算出した体積には有意な差はみられなかった（p＝0.24）．⑤2D-USと摘出標本から算出した長径との間に相関関係はみられなかった（r＝0.19, p＝1.00），一方，3D-USと摘出標本から算出した体積との間には強い相関係数を認めた（r＝0.86, p＝0.58）．

結語：3D-USによる乳癌の腫瘍体積測定は臨床的に有用であり，今後は術前化学療法の効果判定法として有用となる可能性がある．

Purpose: The aim of this study was to investigate the clinical utility and validity of three-dimensional volumetric ultrasound (3D-US) for breast cancer. We also evaluated the possibility of 3D-US as a method for evaluating the clinical response to primary systemic chemotherapy (PSC) for breast cancer.

Subjects and Methods: Ninety-one patients with histologically confirmed breast lesions were enrolled and underwent breast ultrasonography (US) between April 2011 and August 2013. Eight medical technologists performed US using a conventional linear (2D) and 3D type probe. The following findings were examined: 1) the tumor volume measured by different number of the trace sections, 2) the coefficient of variation of measured volume value between benign and malignant tumors, 3) the coefficient of variation of measured volume value in the level of proficiency between benign and malignant tumors, 4) the breast cancer volume measured with US image and resected specimen in different histopathological types, and 5) response evaluation of PSC in the breast cancer. Statistical analysis was performed using the Student’s t-test, the Mann–Whitney U test, and the chi-square test. A p value of ＜0.05 was considered to be statistically significant.

Result: 1) There were no significant differences in the number of the trace sections (p＞0.05). 2) The coefficient of variation of measured volume value of the malignant tumors was significantly higher than that of the benign tumors (p＝0.007). 3) A significant difference of tumor volume was seen before proficiency (p＝0.007), but was not seen after proficiency (p＝0.14). 4) There was no significant difference between scirrhous carcinoma and papillotubular carcinoma with regard to the measured tumor volume (p＝0.13). 5) No correlation was found between the longer axis of 2D-US image and that of resected specimen (r＝0.19, p＝1.00), while strong correlation was found between the measured volume of 3D-US image and that of resected specimen (r＝0.86, p＝0.58).

Conclusion: 3D-US would be reliable method to measure the tumor volume of breast cancer.

キーワード：乳癌；3D超音波；術前化学療法

Key words: breast cancer; three-dimensional volumetric ultrasound; primary systemic chemotherapy

超音波検査技術

研究Research Paper

乳癌超音波診断における3次元超音波検査の有用性Usefulness of 3D-ultrasound in the Breast Cancer Diagnosis