神谷 久美子¹, 豊島 里志², 小野 稔³, 神谷 武志⁴, 光山 昌珠⁵

Kumiko KAMITANI¹, Satoshi TOYOSHIMA², Minoru ONO³, Takeshi KAMITANI⁴, Shoshu MITSUYAMA⁵

¹北九州市立医療センター臨床検査科, ²北九州市立医療センター病理, ³北九州市立医療センター放射線科, ⁴九州大学大学院医学研究院臨床放射線科学分野, ⁵北九州市立医療センター外科

¹Department of Clinical Laboratory, Kitakyushu Municipal Medical Center, ²Department of Pathology, Kitakyushu Municipal Medical Center, ³Department of Radiology, Kitakyushu Municipal Medical Center, ⁴Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, ⁵Department of Surgery, Kitakyushu Municipal Medical Center

キーワード : breast cancer, ultrasonogram, microcalcfication, comedo

目的：マンモグラフィ（MMG）で微小円形または淡く不明瞭な石灰化のみを呈した乳癌の超音波検査による石灰化巣の描出能とその病理学的所見の関係を検討する．方法：術前MMGで微小円形または淡く不明瞭な石灰化のみを示した非浸潤性乳管癌あるいは微小浸潤癌14例を対象に，超音波像での高エコースポットの明瞭さを3段階に分類した．組織亜型をcomedo typeとnon-comedo typeに分類，さらに組織学的因子として石灰化径，管腔拡張の程度，管腔密度，管腔内細胞量を3段階に分類した．結果：組織亜型では，comedo typeを有するものは8例中7例で高エコースポットが描出されたが，non-comedo typeのみの病変では6例中5例で描出は不能であり，comedo typeを有するものは有意に高エコースポットの描出が明瞭であった（P＝0.007）．組織学的所見では，石灰化径の大きいもの（P＝0.02），管腔拡張程度が大きいもの（P＝0.003），管腔密度が高いもの（P＝0.01）が有意に高エコースポットの描出が明瞭であったが，管腔内細胞量と高エコースポットの描出に有意な相関は認めなかった（P＝0.58）．結論：comedo typeでは高エコースポットが良好に描出された．組織学的所見として，石灰化径が大きい，管腔が拡張している，管腔密度が高いほど高エコースポットの描出が明瞭であった．

Purpose: To compare the prominence of echogenic spots with the surrounding hisopathologic findings in breast cancer demonstrating only small round or amorphous microcalcifications on mammography. Subjects and methods: Ultrasonographic findings were investigated in 14 cases of non-invasive ductal carcinoma, with or without minimal invasion, in which small round or amorphous microcalcifications were noted on preoperative mammography. The obviousness of the echogenic spots was classified into three degrees; the histologic subtypes were divided into the comedo type and non-comedo type; and the diameters of the calcifications, degree of ductal dilatation, density of the ducts, and cellularity in the ducts were grouped into three grades. Results: Echogenic spots were demonstrated in 7 of the 8 cases with comedo type lesions, but were not detected in 5 of the 6 cases with only non-comedo lesions. The former demonstrated significantly more obvious echogenic spots than the latter (P=0.007). Histopathologic study of the surrounding tissue revealed that, larger diameter of calcification (P=0.02), greater ductal dilation (P=0.003), and higher duct density (P=0.01) correlated significantly with prominence of echogenic spots; however, no correlation was found between cellularity in the ducts and prominence of the echogenic spots (P=0.58). Conclusion: The histopathologic findings showed that echogenic spots were clearly imaged in cases with comedo-type lesions. In the surrounding tissue, larger diameter of calcification, more dilated ducts, and higher duct density was associated with more prominent echogenic spots.