Desmoid Tumor of the Rectus Abdominis with Urinary Bladder Involvement: A Case Report and Review of Literature

Desmoid tumors (DTs) account for 3% of all soft tissue tumors. They are benign and have no malignant potential with a favorable prognosis, and predominantly occur in young women. The pathogenesis and clinical behavior of DTs are still uncertain. In addition, most cases of DTs were associated with abdominal trauma (including surgery), while genitourinary involvement seemed to be quite rare. Up to now, there has been only one DT case with urinary bladder involvement reported in the literature. We, Hereby, report a 67-year-old male patient with left lower abdominal pain while micturition. Computed tomography (CT) showed a mass located at the lower aspect of the left rectus muscle with an extension attached to the urinary bladder. Based on the pathological findings of tumor specimen, a diagnosis of benign desmoid tumor (DT) of the abdominal wall was made. Laparotomy with wide local excision was carried out. The patient had a smooth postoperative recovery and was discharged after 10 days. Introduction:Historically, MacFarland first described these tumors in 1832. Etymologically, the word desmoid was first coined by Muller in 1838 and is derived from the Greek word desmos, which means band or tendon-like. Stout first used the term fibromatosis in 1961[1,2,3]. Desmoid tumors (DTs) are a kind of rare neoplasm, which represents 3% of all soft tissue tumors and 0.03% of all neoplasms with an incidence of 5 to 6 per million of the population per annum[4,5,6]. DTs predominantly affect young females with a median age of 30 to 40 years old and is more than twice in female than male patients. However, there is no gender preference in older patients [7,8]. Furthermore, the symptoms of DTs are not typical in general. Symptoms can occasionally occur due to the size and location of the tumor but usually are nonspecific. Because of its rarity and unusual behavior, DT is often associated with diagnostic and therapeutic challenges. Computed tomography (CT) and magnetic resonance imaging (MRI) is beneficial for the diagnosis of this tumor but pathological diagnosis is mandatory. Surgical resection is now considered as the most efficient treatment option for patients with DT, because it offers a good chance of long-term survival. Our case is of unusual presentation and finding of abdominal wall desmoid tumor with an extension to urinary bladder in a male patient who is 67 years old. Keywords: desmoid tumor, fibromatosis, spindle cell tumor, urinary bladder.

Desmoid tumor is a rare tumor of the soft tissue. The frequency of occurrence is 2.4 to 4.3 cases per year per million people, which is a very rare disease. We experienced a huge intra-abdominal desmoid tumor which is thought to be the primary mesentery. The case was a male in his 20s. He visited a nearby doctor with a complaint of abdominal bloating and abdominal pain. Abdominal contrast CT revealed a huge abdominal mass with a clear boundary of 35×25 cm in size extending from the upper right abdomen to the pelvis. Surgery was performed with a diagnosis of an intra-abdominal mass. Open abdominal tumor resection. Due to infiltration into the duodenum, transverse colon, and pancreas, right hemicolectomy and duodenal combined resection were performed. The pathological diagnosis was a diagnosis of desmoid tumor.

Desmoid fibromatosis is a rare, aggressive borderline lesion arising from soft tissues. Treatment will depend on the structures that the tumor has involved. Surgery with negative margins is the recommended strategy as it can usually achieve disease control; however, the tumor’s location sometimes does not allow it. Therefore, a combination of medical therapies along with strict surveillance is crucial. We present the case of a 6-month-old boy with a chest mass. After further evaluation, a rapidly growing mediastinal mass involving the sternum and costal cartilage was detected. Desmoid fibromatosis was the final diagnosis.

Objective: To examine the impact of an active surveillance (AS) approach on health-related quality of life (HRQoL) of patients with desmoid-type fibromatosis (DTF). Summary background data: AS is recommended as initial approach in DTF patients. AS might however negatively affect HRQoL due to physical symptoms or stress and anxiety. Methods: In a prospective observational study, the GRAFITI trial (NTR4714), DTF patients were followed during an initial AS approach for three years. HRQoL was assessed by the EORTC QLQ-C30 at baseline, 6, 12 and 24-month follow-up. Patients who completed questionnaires at≥1 time point were included in this analysis of the secondary endpoint. A multivariable linear mixed-effects model with random intercept was conducted to assess trends of HRQoL scores over time and to explore the effect of treatment strategy on HRQoL. Results: All 105 patients enrolled in the GRAFITI trial were eligible for the HRQoL analyses. During 24-month follow-up, 75 patients (71%) continued AS and 30 patients (29%) started an active treatment (AT). DTF patients who continued AS demonstrated relatively stable HRQoL scores during follow-up. HRQoL scores of patients who started AT worsened compared to patients who continued AS, although no significant changes in HRQoL score over time were found in the mixed-model analyses. Overall, DTF patients who started AT scored significantly worse on pain (β=10.08, P=0.039) compared to patients who continued AS. Conclusions: An initial AS approach did not impair HRQoL of DTF patients who continued AS over time, therefore providing further support for AS as the frontline approach in DTF patients. Longitudinal assessment of HRQoL should be part of clinical follow-up to identify patients who may need a change in treatment strategy.

Desmoid tumors (DT) are rare benign tumors with a local invasion potential and recurrence. It is characterized on histology by an abnormal fibroblastic proliferation in a collagenous stroma, in variable proportions leading to heterogeneity of the lesion signal on magnetic resonance imaging (MRI). Current guidelines propose watchful waiting but in case of progression or symptoms, cryotherapy may be a therapeutic option in its extra-abdominal form. Tumor recurrence is mostly detected based on post-contrast magnetic resonance imaging (MRI). Although DWI sequence is the key-sequence for tumor detection in oncologic imaging, there are very few data in literature on diffusion weighted imaging (DWI) in DT generally and even fewer on DT after cryotherapy. DWI changes after cryotherapy may be confusing and suspicious of residual tumor or tumor recurrence when displaying low ADC values; thus knowledge of possible DWI patterns after cryotherapy of DT seem paramount. We found that the early changes of DT after cryotherapy are hyperintensity on DWI sequence with low ADC values (<1.00 × 10-3mm2/s), without corresponding enhancement and a later decrease in signal of the treated lesion on DWI. The freezing-thawing cycles of cryotherapy turn DT into gelatinous necrosis with a slow resorption rate, as reported in the only few studies referring of changes of DWI signals after cryotherapy, which are on renal and prostate models. Hyperintensity on DWI with low ADC values may be seen in early MRI follow-up after cryotherapy of extra-abdominal DT, corresponding with tumor necrosis changes and should not be mistaken with recurrence.KEY MESSAGESMagnetic resonance imaging is the modality of choice for desmoid tumor (DT) follow-up, mainly based on contrast uptake which make data on diffusion weighted imaging (DWI) very rare.Cryotherapy is an accepted therapeutic option for DT that will lead to tumor necrosis.Hyperintensity on DWI with low apparent diffusion coefficient values is a possible expected early pattern on DWI after cryotherapy of DT.

Objective: Desmoid fibromatosis (DF) is a rare, locally aggressive soft tissue tumor. Computed tomography (CT) and magnetic resonance imaging (MRI) play a critical role in the diagnosis of DF and in developing treatment plans. Currently, observation is the primary therapeutic option for a biopsy-confirmed DF. Here, we present a case of a DF that was misdiagnosed as uterine fibroid before surgery. Case report: A 36-year-old woman presented with urinary frequency and a palpable lower abdominal mass, which was suspected as uterine fibroid based on sonography and CT. During surgery, an abdominal wall mass was found to be densely adherent to the bladder. Permanent pathology revealed that the tumor was desmoid-type fibromatosis. Conclusion: Desmoid tumors often occur in the abdomen, abdominal wall, extremities, head, and neck. Abdominal wall DF involving the rectus abdominis muscles is most commonly observed. Conversely, desmoid tumors involving the bladder are less described. The review of similar cases reported since 1985 showed that partial cystectomy was primarily performed for complete resection.