TWO CASES OF ABDOMINAL DESMOID TUMOR

Two cases of desmoid tumor are presented with a review of 74 cases reported in Japan. The first case was a 38-year-old female with a non-tender mass in the right lower abdominal wall, which was 4.5×2.5×2.0 cm in size and growing invasively within the internal oblique abdominal muscle. The second case was a 39-year-old female with a non-tender mass in the left lower abdominal wall, which was 4.5×4.4×2.5 cm in size and growing invasively within the internal obliaque, rectus and transverse abdominal muscles. Both patients' tumors were resected completely, including the surrounding nomal tissues within 1 cm from the tumor. Defects of the fasciae were approximated primarily by adding multiple incisions in the surrounding fasicae to reduce tension. There has been no evidence of recurrence 2 years and 10 months and 11 months after surgery, respectively. Review of the 74 reported cases indicated this tumor is found more frequently in females aged from 20 to 40. About 90% of tumors originated from the rectus or internal oblique abdominal muscle. US and CT were useful for the diagnosis. Charactristic findings on US were a hypoechoic mass, sometimes heterogenous, with an irregular and slightly unclear margin. Recurrence of the tumor was reported 5 patients (6.8%). It is therefore considered that complete resection is necessary to treat this tumor.