The Role of Shear Wave Elastography In Diagnosis of Soft Tissue Tumours

To obtain more information about the characteristics and stiffness of soft tissue tumors using shear wave elastography (SWE) and magnetic resonance imaging (MRI). This study involved 83 patients diagnosed with a soft tissue mass who underwent surgical excision. These patients were evaluated with MRI and then ultrasonographically and SWE values were measured. The values obtained were compared with the pathology results of the patients following surgical excision. Correlations between SWE and tumour size, grade, and content components were investigated.A total of 52 benign and 31 malignant soft tissue tumors were diagnosed pathologically. The SWE values measured were significantly higher in the malignant and high grade tumors (pswe=11.2) compared with the benign tumors (pswe=3.07) (p<0.001). A significant correlation was determined between the SWE values and the fibrotic component in the content of the excised tumour (Spearman correlation: r=0.571; p<0.001). High SWE values were obtained, close to malignant values in desmoid tumors and those with a dense fibrotic component, despite being benign. The study results showed that high SWE values were associated with the mass content and malignancy in certain tumors. Positive correlations were observed between SWE values and tumor size, grade, and fibrotic component density. When SWE is combined with MRI and ultrasonography, the awareness of benign lesions is increased and may reduce the need for biopsy in benign lesions.

Objective: Neuromuscular choristoma (NMC) is a rare developmental lesion that may give rise to desmoid-type fibromatosis (DTF) within the same nerve territory (NMC-DTF). While MRI features of NMC are well established, the natural history of progression to NMC-DTF has not been systematically described. This study aimed to define radiological groups from NMC to NMC-DTF using serial MRI and a literature review.

Methods: Following IRB approval, the authors retrospectively analyzed 28 patients with NMC from their institutional database. Diagnosis was based on pathology or classic clinicoradiological features. Sequential MR images were reviewed to evaluate nerve enlargement, enhancement patterns, low T1/T2 foci, and NMC-DTF formation. Cases were classified into 3 radiological groups: 1) classic NMC with typical MRI features (group I), 2) NMC plus, with atypical features (foci of low T1/T2 signal intensity and/or at least moderate postcontrast enhancement; group II), and 3) NMC-DTF with a mass outside of the epineurium (group III). Data were correlated with pathology results and prior reports from the literature.

Results: Of the 28 patients, 24 underwent serial MRI. Eleven patients presented with group I features, 4 with group II, and 9 with group III. Among group I patients with follow-up imaging, 4 (36.4%) progressed to group III over a mean of 6.2 years and 1 (9.1%) to group II. All 4 group II patients (100%) developed NMC-DTF within a mean of 3.0 years. All group III patients demonstrated NMC-DTF extending beyond the epineurium. No prior cases in the literature documented radiological progression from NMC to NMC-DTF on serial MR images.

Conclusions: The authors propose a framework for NMC progression based on radiological features, identifying group II as being high risk and a potential transitional phase for the formation of DTF. Structured surveillance with serial MRI is essential to prevent iatrogenic triggers and improve management strategies in patients with NMC.

Case: A 54-year-old man received radiation therapy (50 Gy) for popliteal desmoid fibromatosis. After 17 years, he developed an enlarging mass in the same location. Initial biopsy suggested recurrent desmoid, but a repeat biopsy revealed sclerosing rhabdomyosarcoma. Despite chemotherapy and transfemoral amputation, he developed pulmonary and chest wall metastases.

Conclusion: The 17-year latency period and tumor location within the prior radiation field are consistent with radiation-associated malignant transformation; however, definitive causality cannot be established. Orthopaedic surgeons should maintain a low threshold for rebiopsy of any new or changing mass in previously irradiated fields.

Endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) is widely used for the pathological diagnosis of pancreatic diseases. However, needle tract seeding (NTS) remains a clinical concern, particularly when the puncture route is not included in the surgical resection field. We report a case in which distinguishing NTS from other pathologies was challenging. A woman in her 70s underwent EUS-FNB via the gastric antrum for a 10-mm pancreatic head lesion, which was diagnosed as adenocarcinoma (cT1bN0M0, Stage IA). She subsequently underwent pancreaticoduodenectomy (pT3N0M0, Stage IIA) without adjuvant chemotherapy. Two years postoperatively, a 30-mm submucosal tumor was detected in the stomach. Although positron emission tomography-computed tomography demonstrated fluorodeoxyglucose uptake, three separate sessions of EUS-FNB failed to yield a definitive diagnosis, with NTS being strongly suspected. Partial gastrectomy was performed. Histopathology revealed a fascicular proliferation of spindle-shaped cells with nuclear β-catenin positivity, leading to the diagnosis of a desmoid fibromatosis (DF). This case underscores that although NTS should be considered when a lesion arises along the EUS-FNB puncture tract, alternative diagnoses, including DF, must also be carefully evaluated.

Colorectal cancer (CRC) recurrence found in the abdominal wall is a rare but devastating event following colorectal adenocarcinoma resection. Desmoid tumours (DTs) are benign, locally invasive tumours which can present clinically and radiologically similar to CRC recurrence in the abdominal wall. Although they have a superior prognosis, they have the potential for significant morbidity. This poses both a diagnostic and treatment dilemma requiring thorough investigation through imaging, histology and multidisciplinary discussion to optimise patient outcomes. We report two cases which involve the identification of abdominal wall masses highly suspicious for recurrence during routine surveillance in the period post-CRC resection. In the first case, the mass was excised, but surveillance was deemed appropriate in the second case following core biopsy. Histology confirmed DTs in both cases. Differentiating between abdominal wall recurrence and DTs represents a significant diagnostic challenge and a dilemma in regard to the decision to resect or not.