A 28-year-old woman with a history of an appendectomy presents with a nontender palpable mass in the right lower quadrant abdominal incision. The following statement(s) is/are true concerning the diagnosis and management of this patient

a. The best diagnostic test involves imaging of the abdominal wall by either CT or MRI

Desmoid tumors are fibromatous tumors that may resemble low-grade fibrosarcoma but never metastasize. The tumor often infiltrates adjacent muscle and has a high incidence of recurrence despite seemingly adequate gross resection. The highest frequency is in women of childbearing age of which over 90% of tumors are abdominal in location. For abdominal wall desmoid tumors, approximately one-third are associated with a previous operation at the tumor site. The most frequent presenting symptom is a nontender, palpable abdominal wall mass. Diagnostic imaging is best carried out by CT or MRI, which delineate the extent of involvement of the layers of the abdominal wall and potential intraperitoneal extension. Initial treatment of abdominal wall desmoid tumors is surgical. Because the margins of the tumor are not easily determined and because the tumor often infiltrates muscle and periosteum, limited margins around the gross tumor frequently result in microscopic tumor at the margin. Recurrence rates for abdominal desmoid tumors vary from 9% to 40%, and recurrence is frequent with inadequate margins. A 5-cm margin of resection is considered adequate with mono bloc resection of rib cage, pubic or iliac bone or involved portions of organs such as bladder to achieve these margins. Reconstruction of the abdominal wall with polypropylene mesh is necessary in most cases. In patients in whom adequate margins of resection are achieved, there is no benefit from adjuvant radiotherapy. Second and third resections after recurrence have been associated with no higher rate of recurrence than primary resection. Radiotherapy alone has achieved local control in desmoid tumor in as many as 100% of tumors treated primarily and 75% of recurrent tumors. Radiation doses at least 60 Gy are considered necessary for consistent control. The large radiation dose risks major damage to adjacent bowel and therefore primary radiation treatment of abdominal wall desmoid tumors has a limited role.