A Case of Lung Metastasis of Mesoblastic Nephroma in Adulthood

Mesoblastic nephroma is a neoplasm of the kidney which is characterized by interlacing bundles of spindle mesenchymal cells. It is usually diagnosed during the first six months of life and is mostly benign. Incidence in adults is exceedingly rare. In most cases, only total excision is required without postoperative adjuvant therapy, and the rare cases of local recurrence have usually been related to incomplete removal. However, mesoblastic nephroma may behave aggressively, in contrast to a congenital mesoblastic nephroma. Several cases of metastatic mesoblastic nephroma have been previously described. We report herein a case of a 42-year-old woman with mesoblastic nephroma which recurred as a large metastatic lung mass seven years after the nephrectomy. The patient presented with chest wall discomfort for four days. Seven years previously, total nephrectomy had been performed because of a right renal tumor which had been diagnosed as a mesoblastic nephroma. There had been no evidence of recurrence for five years, after which she discontinued follow-up. On readmission two years later, chest X-ray and CT scan revealed a large lung mass in the left upper lobe. It was completely excised and the pathologic examination was identical with that of the original renal tumor. Synovial sarcoma was excluded because the fusion transcripts of the SYT-SSX fusion gene associated with the t(X;18) translocation were negative. The final diagnosis was a lung metastasis of mesoblastic nephroma and the patient remained free of disease for 7 months postoperatively.

성인에서 발생한 중배엽성 신종의 폐전이 1예

저자 등은 성인에서 드물며, 또한 국내에서 원격전이를 일으킨 예가 보고된 바 없는 중배엽성 신종이 35세 여자 환자에서 발생하여 신적출술 7년 후 폐전이로 하나의 큰 종괴를 형성한 증례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.