A Large Sporadic Intra-abdominal Desmoid-Type Fibromatosis in a Young Male: A Case Report

We present a case of a young male with a sporadic 31 ? 25 ? 12 cm desmoid type fibromatosis (DTF) arising from the ileocolic mesentery that was complicated by mass effect on bowel and intra-abdominal organs requiring surgical intervention. The tumor biopsy confirmed the diagnosis of DTF. No evidence of familial adenomatous polyposis or Gardner syndrome was identified. The tumor was surgically excised and intimately associated with the bowel requiring ileocolonic resection with primary anastomosis. At 3-months follow up, surveillance MRI showed no residual or recurrent lesion. A multi-disciplinary approach to this patient’s diagnosis and treatment allowed for an accurate diagnosis, efficient treatment, and follow up plan.

We report a case of fibromatosis of cheek in an adult female that was managed successfully by surgical intervention and to discuss the review of literature on this subject.

As targeted therapy, tyrosine kinase inhibitors have been recently reported to contribute to the treatment of desmoid fibromatosis (DF). Thus, the purpose of this study was to assess the efficacy and safety of anlotinib, a novel multi-kinase angiogenesis inhibitor, in patients with DF. We retrospectively collected the clinical medical records of patients with extremity DF who received anlotinib between January 2019 and January 2020 in our center. Anlotinib was started with a dose of 8 mg daily and adjusted according to the drug-related toxicity. In total, 21 (6 male, 15 female) consecutive patients with DF were enrolled. None of the patients achieved a complete response, but eight (38.1%) patients achieved a partial response and ten patients (47.6%) achieved disease stability. Three (14%) patients developed progressive disease and the 3-, 6-, and 12-month PFS rates were 95.2%, 90.5%, and 84.0%, respectively. The disease control rate was 86.0% (18/21) and the objective response rate was 38.1% (8/21). Moreover, 15/21 (71.4%) patients achieved a reduction in tumor size, accompanied with a decrease in T2-weighted signal intensity on magnetic resonance imaging and clinical benefit. Anlotinib was effective against DF with an acceptable safety profile, and significantly slowed the disease progression.

The response of desmoid tumors (DTs) to chemotherapy is evaluated with Response Evaluation Criteria in Solid Tumors version 1.1 (RECIST 1.1) in daily practice and clinical trials. MRI shows early change in heterogeneity in responding tumors due to a decrease in cellular area and an increase in fibronecrotic content before dimensional response. Heterogeneity can be quantified with radiomics. Our aim was to develop radiomics-based response criteria and to compare their performances with clinical and radiologic response criteria. Forty-two patients (median age, 38.2 years) were included in this retrospective multicenter study because they presented with progressive DT and had an MRI examination at baseline, which we refer to as “MRI-0,” and an early MRI evaluation performed after the first chemotherapy cycle (mean time after first chemotherapy cycle, 3 months [SD, 28 days]), which we refer to as “MRI-1.” After signal intensity normalization, voxel size standardization, discretization, and segmentation of DT volume on fat-suppressed contrast-enhanced T1-weighted imaging, 90 baseline and delta 3D radiomics features were extracted. Using cross-validation and least absolute shrinkage and selection operator-penalized Cox regression, a radiomics score was generated. The performances of models based on the radiomics score, modified Response Evaluation Criteria in Solid Tumors, European Association for the Study of the Liver criteria, Cheson criteria, Choi criteria, and revised Choi criteria from MRI-0 to MRI-1 to predict progression-free survival (PFS, as defined by RECIST 1.1) were assessed with the concordance index. The results were adjusted for performance status, tumor volume, prior chemotherapy, current chemotherapy, and beta-catenin mutation. There were 10 cases of progression. The radiomics score included four variables. A high score indicated a poor prognosis. The radiomics score independently correlated with PFS (adjusted hazard ratio = 5.60, p = 0.003), and none of the usual response criteria independently correlated with PFS. The prognostic model based on the radiomics score had the highest concordance index (0.84; 95% CI, 0.71-0.96). Quantifying early changes in heterogeneity through a dedicated radiomics score could improve response evaluation for patients with DT undergoing chemotherapy.

Pancreas is an exceptionally rare location for desmoid tumors. There are very few case reports of pancreatic fibromatosis in the English radiology literature. We present a case of a 45-year-old male with a mixed solid and cystic desmoid tumor of the pancreas which was surgically resected and was followed by recurrence in the mesentery. This will be the first case report of pancreatic desmoid with documented recurrence of fibromatosis in the mesentery which was also surgically resected and confirmed on pathology. In this case report, we discuss this entity’s radiological findings with pathology correlation, clinical findings and management along with literature review.

Diagnosing desmoid-type fibromatosis (DTF) requires an invasive tissue biopsy with beta-catenin staining and CTNNB1 mutational analysis, and is challenging due to its rarity. The aim of this study was to evaluate radiomics for distinguishing DTF from soft tissue sarcomas (STS), and in DTF, for predicting the CTNNB1 mutation types. Patients with histologically confirmed extremity STS (non-DTF) or DTF and at least a pretreatment T1-weighted (T1w) MRI scan were retrospectively included. Tumors were semi-automatically annotated on the T1w scans, from which 411 features were extracted. Prediction models were created using a combination of various machine learning approaches. Evaluation was performed through a 100x random-split cross-validation. The model for DTF vs. non-DTF was compared to classification by two radiologists on a location matched subset. The data included 203 patients (72 DTF, 131 STS). The T1w radiomics model showed a mean AUC of 0.79 on the full dataset. Addition of T2w or T1w post-contrast scans did not improve the performance. On the location matched cohort, the T1w model had a mean AUC of 0.88 while the radiologists had an AUC of 0.80 and 0.88, respectively. For the prediction of the CTNNB1 mutation types (S45 F, T41A and wild-type), the T1w model showed an AUC of 0.61, 0.56, and 0.74. Our radiomics model was able to distinguish DTF from STS with high accuracy similar to two radiologists, but was not able to predict the CTNNB1 mutation status.