Comparison of Bone Scan Findings with Collagenase Activities in Patients with Breast Cancer

유방암 환자에서 종양조직내 Collagenase 활성도와 골스캔과의 비교

Purpose : It has been known that the activity of extracellular matrix degradative enzymes such as collagenase correlate well with the metastatic potential of various tumor cells in experimental study. This study was aimed at comparing the activities of type IV collagenase with bone scan findings in patients with breast cancer. Materials and Methods : We retrospectively correlated bone scan findings with the results of immunohistochemical staining for 92kDa, 72kDa type IV collagenase in 28, and 30 patients with metastatic breast cancer, respectively, as well as 23, and 27 patients with primary breast cancer, respectively. The immunohistochemical staining was performed with tissue specimens obtained from primary or metastatic breast tumor lesions. The amounts of the enzyme were graded from 0 to 4 and scored by multiplication with the percentage of tumor cells. The confidence of bone scan interpretation for metastasis was also scored from 1 to 5 with increasing probability. Results : There was a significant difference in enzyme scores between patients with and without metastasis. In patients with primary breast cancer group, the frequency of patients with enzyme score of less than 170 were 96%(26/27) and 100%(26/26) with 92kDa and 72kDa collagenase, respectively. In contrast, in patients with metastatic breast cancer group, the frequency of patients with enzyme score of more than 200 were 93%(28/30) and 87%(26/30) with 92kDa and 72kDa collagenase, respectively. All patients with each enzyme score of less than 170 show no active bony metastasis, however, there were variable bone scan findings in patients with each enzyme score of more than 200. Conclusion : Bone scan is useful to confirm, localize or follow up of bony metastasis in patients with each enzyme scores of more than 200. Acitve metastatic lesions were hardly seen on the bone scintigraphy in patients with collagenase scores of less than 170.

기저막 성분인 type IV collagen을 분해하는 type IV collagenase의 농도와 종양의 전이사이에 상관관계가 있다는 동물 실험보고가 있다. 저자들은 유방암환자의 종양조직내 type IV collagenase의 농도와 골스캔상 골전이 소견과 비교하여 그 의의를 알아보고자 하였다. 원발성 및 전이성 유방암 환자의 종양조직에서 92kDa 및 72kDa type IV collagenase에 대한 면역조직화학염색을 각각 57명, 56명 환자에서 시행하여 각 효소 농도를 평가하고 골스캔상 골전이 소견을 관찰하고 등급을 부여하였다. 면역조직화학적으로 평가한 각 효소의 농도는 원발성 유방암과 전이성 유방암 환자 사이에 큰 차이가 있었으며, 골스캔 소견과 효소농도를 상호 비교한 결과 각 효소의 농도가 170이하일 경우에는 골스캔상 활동적인 골전이 소견을 볼 수 없었으나 효소의 농도가 200이상일 경우 골스캔 소견은 정상에서 골전이 소견까지 매우 다양하게 분포하였다. 결론적으로, 면역 조직화학적으로 측정한 92kDa 및 72kDa collagenase의 농도가 170이하일 때는 골스캔상 대부분 정상소견을 보여 골전이의 확률이 낮았다. 반면에 각 효소치의 농도가 200이상일 경우에는 골전이의 확진과 병소의 위치를 확인하고 추적검사를 위해서는 골스캔이 필요하다고 사료된다.