Evidence-based MR imaging follow-up strategy for desmoid-type fibromatosis

Diffuse-Type Tenosynovial Giant Cell Tumor: What Are the Important Findings on the Initial and Follow-Up MRI?

Tenosynovial giant cell tumor (TSGCT) is a rare soft tissue tumor that involves the synovial lining of joints, bursae, and tendon sheaths, primarily affecting young patients (usually in the fourth decade of life). The tumor comprises two subtypes: the localized type (L-TSGCT) and the diffuse type (D-TSGCT). Although these subtypes share histological and genetic similarities, they present a different prognosis. D-TSGCT tends to exhibit local aggressiveness and a higher recurrence rate compared to L-TSGCT. Magnetic resonance imaging (MRI) is the preferred diagnostic tool for both the initial diagnosis and for treatment planning. When interpreting the initial MRI of a suspected TSGCT, it is essential to consider: (i) the characteristic findings of TSGCT-evident as low to intermediate signal intensity on both T1- and T2-weighted images, with a blooming artifact on gradient-echo sequences due to hemosiderin deposition; (ii) the possibility of D-TSGCT-extensive involvement of the synovial membrane with infiltrative margin; and (iii) the resectability and extent-if resectable, synovectomy is performed; if not, a novel systemic therapy involving colony-stimulating factor 1 receptor inhibitors is administered. In the interpretation of follow-up MRIs of D-TSGCTs after treatment, it is crucial to consider both tumor recurrence and potential complications such as osteoarthritis after surgery as well as the treatment response after systemic treatment. Given its prevalence in young adult patents and significant impact on patients' quality of life, clinical trials exploring new agents targeting D-TSGCT are currently underway. Consequently, understanding the characteristic MRI findings of D-TSGCT before and after treatment is imperative.

MRI T2 mapping assessment of T2 relaxation time in desmoid tumors as a quantitative imaging biomarker of tumor response: preliminary results

Objectives

Because size-based imaging criteria poorly capture biologic response in desmoid-type fibromatosis (DF), changes in MRI T2 signal intensity are frequently used as a response surrogate, but remain qualitative. We hypothesized that absolute quantification of DF T2 relaxation time derived from parametric T2 maps would be a feasible and effective imaging biomarker of disease activity.

Methods

This IRB-approved retrospective study included 11 patients with DF, managed by observation or systemic therapy, assessed by 3T MRI. Tumor maximum diameter, volume, and T2-weighted signal intensity were derived from manual tumor segmentations. Tumor:muscle T2 signal ratios were recorded. Two readers measured tumor T2 relaxation times using a commercial T2 scanning sequence, manual ROI delineation and commercial calculation software enabling estimation of reader reliability. Objective response rates based on RECIST1.1 and best responses were compared between size-based and signal-based parameters.

Results

Median patient age was 52.6 years; 8 subjects were female (73%). Nine patients with longitudinal assessments were followed for an average of 314 days. Median baseline tumor diameter was 7.2 cm (range 4.4 - 18.2 cm). Median baseline T2 was 65.1 ms (range 40.4 - 94.8 ms, n=11); median at last follow-up was 44.3 ms (-32% from baseline; range 29.3 - 94.7 ms, n=9). T2 relaxation times correlated with tumor:muscle T2 signal ratios, Spearman p=0.78 (p<0.001). T2 mapping showed high inter-reader reliability, ICC=0.84. The best response as a percentage change in T2 values was statistically significant (mean -17.9%, p=0.05, paired t-test) while change in diameter was not (mean -8.9%, p=0.12).

Conclusions

Analysis of T2 relaxation time maps of DF may offer a feasible quantitative biomarker for assessing the extent of response to treatment. This approach may have high inter-reader reliability.

MRI-based navigated cryosurgery of extra-abdominal desmoid tumors using skin fiducial markers: a case series of 15 cases

BACKGROUND

Precision surgery is becoming increasingly important in the field of Orthopaedic Oncology. Image-guided percutaneous cryosurgery (CRA) has emerged as a valid treatment modality for extra-abdominal desmoid tumors (EDTs). To date, most CRA procedures use CT-based guidance which fails to properly characterize tumor segments. Computer-guided MRI navigation can address this issue however, the lack of a fixed landmark for registration remains a challenge. Successful CRA correlates directly with precision approaches facilitated by intraoperative imaging guidance. This is the first study that attempts to assess the feasibility and efficacy of a novel approach of using skin fiducial markers to overcome the challenge of a MRI-based navigation CRA for symptomatic or progressive EDTs.

METHODS

In this retrospective study conducted between 2018 and 2020, 11 patients at a single center with symptomatic or progressive EDTs were treated with CRA using intraoperative MRI navigation. Fifteen cryosurgery procedures were performed, each adhering to a personalized pre-operative plan. Total tumor size, viable and non-viable portions pre- and post-operation, and SF-36 questionnaire evaluating subjective health were recorded.

RESULTS

All CRAs demonstrated 100% adherence to the predetermined plan. Overall, tumor size decreased Median= -56.9% [-25.6, -72.4]) with a reduction in viable tissue, (Median= -80.4% [-53.3, -95.2]). Four patients required additional CRAs. Only one patient's tumor did not reduce in size. One patient suffered from local muscle necrosis. Pre-operation, the average physical and mental scores 41.6 [29.4, 43] and 26.3 [17.6, 40.9] respectively. Post-operation, the average physical and mental scores were 53.4[38, 59.7] and 38 [31.2, 52.7] respectively.

CONCLUSION

These findings provide an early indication of the feasibility and efficacy of performing percutaneous cryosurgery using skin fiducial marker registration for MRI-computed navigation to treat EDTs safely. Larger cohorts and multicenter evaluations are needed to determine the efficacy of this technique.

Desmoid Tumor of the Posterior Neck: A Case Report

Desmoid tumors are rare. They account for roughly 0.03% of all neoplasms and less than 3% of all soft tissue tumors. They are locally aggressive tumors with no known metastatic potential or dedifferentiation. A 29-year-old woman with no family history of neoplasms presented with a mass in the cervical region and moderate pain that had developed a year before. The patient underwent marginal resection of the bilateral posterior and lateral compartments of the neck. The histopathological report confirmed the diagnosis of desmoid tumor with nuclear positivity for beta-catenin. The patient received radiotherapy but did not show a favorable response; she has stable disease and takes colchicine at one-year follow-up.

Desmoid-type fibromatosis: imaging features and course

Desmoid-type fibromatosis (DF) is a soft tissue tumor characterized by infiltrative growth and a tendency toward local recurrence, while it exhibits self-limiting behavior and shows spontaneous regression. With its unpredictable behavior, a change in treatment strategies from initial surgery to nonsurgical management has been proposed, and active surveillance is currently widely chosen as the initial treatment strategy for DF. We reviewed the imaging features of DF regarding its clinical course, focusing on regression cases, postoperative cases, and imaging changes after systemic treatment.

Semi-Automatic Volumetric and Standard Three-Dimensional Measurements for Primary Tumor Evaluation and Response to Treatment Assessment in Pediatric Rhabdomyosarcoma

Current prognostic classification of rhabdomyosarcoma in children requires precise measurements of the tumor. The purpose of the study was to compare the standard three-dimensional (3D) measurements with semi-automatic tumor volume measurement method concerning assessment of the primary tumor size and the degree of response to treatment for rhabdomyosarcoma in children. Magnetic Resonance Imaging data on 31 children with treated rhabdomyosarcoma based on the Cooperative Weichteilsarkom Studiengruppe (CWS) guidance was evaluated. Tumor sizes were measured by two methods: 3D standard measurements and semi-automatic tumor volume measurement (VOI) at diagnosis, and after 9 and 17/18 weeks of the induction chemotherapy. Response to treatment and prediction values were assessed. The tumor volume medians calculated using VOI were significantly higher in comparison with those calculated using the 3D method both during the diagnosis as well as after 9 weeks of the chemotherapy and during the 17-18th week of the treatment. The volume measurements based on the generalized estimating equations on the VOI method were significantly better than the 3D method (p = 0.037). The volumetric measurements alone can hardly be considered an unequivocal marker used to make decisions on modification of the therapy in patients with rhabdomyosarcoma.

Efficacy and safety of apatinib for patients with advanced extremity desmoid fibromatosis: a retrospective study

PURPOSE

Desmoid fibromatosis (DF) is a locally aggressive connective-tissue tumor arising in deep soft tissues. Although multiple therapeutic modalities have been demonstrated effective for DF, there is no standard systemic treatment for progressive and recurrent DF. As a part of systemic treatment, tyrosine kinase inhibitors have shown promising activity against DF with tolerable toxicity profiles. Thus, the aim of this study was to investigate the efficacy and safety of apatinib, a novel multi-target angiogenesis inhibitor, in patients with DF.

METHODS

We retrospectively analyzed the medical records of patients with advanced extremity DF regularly treated with apatinib between October 2017 and January 2020 in our center. Apatinib was initially administered with a dose of 250 mg daily and the dose was adjusted according to the toxicity. Tumor response was assessed by the Response Evaluation Criteria in Solid Tumors 1.1 criteria. The primary endpoint was progression-free survival (PFS); objective response rates and drug-related adverse events were also evaluated.

RESULTS

A total of 22 (6 male, 16 female) patients with advanced extremity DF were included. The mean medication time was 17 months. None of the patients reached a complete response, but ten (45.5%) patients achieved partial response, and 11 patients (50%) achieved stable disease. One (4.5%) patient developed progressive disease, and the 1-year PFS rate was 95.2%. The disease control rate was 95.4% (21/22) and the objective response rate was 45.5% (10/22). Meanwhile, 18 (81.8%) patients with a tumor shrinkage were accompanied by a decreased signal intensity of lesions in T2-weighted magnetic resonance imaging. The most frequent adverse events included hand-foot syndrome (n = 7, 31.8%), fatigue (n = 6, 27.2%), local pain (n = 4, 18.1%), diarrhea (n = 4, 18.1%).

CONCLUSION

Apatinib is an effective and well-tolerated option for patients with advanced extremity DF. Indeed, further prospective, randomized studies with larger cases are required to fully explore the clinical utility of apatinib in DF.

Desmoid tumors: To treat or not to treat, That is the question

Desmoid tumors (DTs) are a rare disease of intermediate malignancy characterized histologically by a locally aggressive, monoclonal, fibroblastic proliferation and clinically by a variable and often unpredictable course. For decades, surgical resection has been the standard initial treatment approach; however, more recently, a paradigm shift toward a more conservative treatment strategy has been introduced. More than 5 years ago, The Desmoid Tumor Working Group started a consensus initiative in Europe with the aim of harmonizing the strategy among clinicians and setting up treatment recommendations for patients with DTs. This review summarizes the latest joint, global, evidence-based guideline approach to DT management. Moreover, a number of gray areas in the treatment recommendations are discussed, and possible future perspectives on the treatment armamentarium for patients with DTs are presented.

The Activity and Safety of Anlotinib for Patients with Extremity Desmoid Fibromatosis: A Retrospective Study in a Single Institution

Purpose

Desmoid fibromatosis (DF) is an aggressive fibroblastic neoplasm with a high propensity for local recurrence. Although multiple therapeutic modalities seem effective for DF, the standard systemic treatment for symptomatic and progressive DF remains controversial. As targeted therapy, tyrosine kinase inhibitors have been recently reported to contribute to the treatment of 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.

Patients and Methods

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. Tumor response was assessed by the Response Evaluation Criteria in Solid Tumors 1.1 criteria. Progression-free survival (PFS) was identified as the primary endpoint and analyzed using the Kaplan–Meier method.

Results

In total, 21 (6 male, 15 female) consecutive patients with DF were enrolled. The median medication time was nine months (Q1, Q3: 7.5, 10.5). 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.

Conclusion

Anlotinib was effective against DF with an acceptable safety profile, and significantly slowed the disease progression. Further, multicenter studies with a longer follow-up time are needed to characterize fully the clinical application of anlotinib in DF.

The value of the black fiber sign on T1-weighted images for predicting stability of desmoid fibromatosis managed conservatively

OBJECTIVES

It is challenging to know at the first which patients with desmoid fibromatosis (DF) are better suited to conservative or aggressive treatment. To investigate whether the low signal intensity bundles on T1- or T2-weighted images (WI), termed the "black fiber sign (BFS)," can predict non-progressive behavior in the conservative approach.

METHODS

This retrospective study included 59 patients with primary DF managed with wait-and-see approach from 2005 to 2018 and serial MR images were analyzed. Three observers blinded to the patient information verified the presence or absence of BFS on baseline T1 or T2WI. The likelihood of progression-free survival (PFS) after ascertaining the presence or absence of the BFS was estimated using the Kaplan-Meier method and analyzed with the log-rank test.

RESULTS

PFS was significantly higher in cases with BFS than without BFS on T1WI (p < 0.01), but there was no significant difference in PFS between cases with and without BFS on T2WI. Multivariable Cox proportional hazards analysis revealed that the absence of BFS on T1WI was a high-risk factor for progression (hazard ratio, 14.9; p < 0.01). Drastic tumor regression was apparent with significantly increased low-signal area in cases with BFS on T1WI. Intra- and interobserver reliabilities of BFS on T1WI were in almost-perfect agreement (κ > 0.8).

CONCLUSION

Our retrospective observational data support that presence of BFS in baseline MRI may be a predictor for progression-free survival of DF. BFS on T1WI is easily identifiable and can be utilized clinically in patients with DF.

KEY POINTS

• We proposed a new imaging marker for prediction of desmoid fibromatosis progression. • The absence of black fiber sign predicted a high risk of disease progression.