Abdominal wall desmoid mimicking intra-abdominal mass: MR features

Giant desmoid tumour mimicking recurrent uterine myoma in a nulliparous young Nigerian: a case report

Background

Desmoid tumors are rare lesions. Although they demonstrate tumor characteristics, such as infiltrative growth and tendency towards local recurrence, they lack the ability to metastasize. To date, the cause of desmoid tumors is unknown. They can occur in both sexes, but predominant slightly in women, including nulliparous women, of reproductive age, but mostly during and after pregnancy.

Case presentation

A 36-year-old nulliparous Nigerian woman presented with a large desmoid tumor of the anterior abdominal wall, mimicking recurrent leiomyoma. At presentation, she had a painless abdominal mass for 1 year, which was first noticeable as a small induration that progressively increased in size. The patient had a previous surgical history of open myomectomy for symptomatic fibroids of 3 years duration, prior to presentation. Treatment comprised a complete excision of the tumor with a wide margin and partial omentectomy and the anterior abdominal wall closed in layers, though without prosthesis. The patient subsequently developed incisional hernia.

Conclusions

Large desmoid tumors may be misdiagnosed or mistaken for uterine leiomyoma or other abdominal or pelvic tumors. Attention should therefore be paid to detailed patient history and systematic clinical evaluation. To guard against incisional hernia associated with surgical resection of huge desmoid tumors, mesh reconstruction is recommended.

Huge desmoid tumor of the anterior abdominal wall mimicking an intraabdominal mass in a postpartum woman: a case report

Desmoid tumors are benign neoplasms that most often arise from muscle aponeurosis and have been associated with both trauma and pregnancy. The etiology of desmoids has not been determined. We report the case of anterior abdominal wall desmoid tumor in a female patient with previous history of cesarean section. Preoperative ultrasound and computed tomography demonstrated a large mass mimicking a large hematoma or an intraabdominal mass. The tumor was removed by wide excision with safe margins. The abdominal wall defect was reconstructed with polypropylene mesh. Subsequent histology revealed a desmoid tumor. Desmoid tumors in females are often associated with pregnancy or occur post-partum. The reasons behind this association are unclear. The most common sites are in the abdominal muscles.

Abdominal wall desmoid tumor mimicking a subserosal uterine leiomyoma

Desmoid tumors are cytologically bland fibrous neoplasms originating from musculoaponeurotic structures throughout the body. The cause of desmoid tumors is uncertain, but may be related to trauma or hormonal factors, or may have a genetic association. These tumors can be found in some young women during pregnancy or just after giving birth. We report herein a case of desmoid tumor on the inner aspect of the abdominal wall that mimicked a large subserosal uterine leiomyoma. Initial clinical examination of the patient suggested a large abdominal wall tumor, while the imaging techniques including transabdominal ultrasound and magnetic resonance imaging suggested a large subserosal uterine leiomyoma as the initial diagnosis. This case emphasizes the importance of clinical examination during the diagnostic process.

MR imaging of soft-tissue masses of the extraperitoneal spaces

Magnetic resonance (MR) imaging has an increasing role in evaluating soft-tissue masses of the extraperitoneal spaces. Since the MR imaging features of most soft-tissue masses are nonspecific, prediction of a specific histologic diagnosis remains a challenge for the radiologist. However, there are certain specific MR imaging appearances that are helpful for more accurate diagnosis. Some histologic components, such as myxoid stroma, collagen fibers, calcification, and fat, have characteristic MR imaging features. Recognition of these features can assist the radiologist in limiting the differential diagnosis. Dynamic enhancement patterns can reflect the vascularity of masses and may be useful in diagnosis, especially in differentiating benign from malignant soft-tissue masses. Familiarity with specific signs and knowledge of diagnostic pitfalls are also important for shortening the list of differential diagnoses. Specific signs are the target sign, the bowl of fruit sign, a whorled appearance, a flow void, speckled enhancement, associated lymphadenopathy, and extension into the intervertebral foramen. Diagnostic pitfalls are as follows: a myxoid stroma simulating cystic degeneration and necrosis, collagen fibers simulating hemorrhage, a fat component simulating extraperitoneal fat, extensive intratumoral hemorrhage simulating hematoma, benign masses mimicking malignant ones, malignant masses mimicking benign ones, and peritoneal lesions mimicking extraperitoneal masses.