Desmoid fibromatosis: MRI features of response to systemic therapy

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.

Oral vinorelbine in young patients with desmoid-type fibromatosis

BACKGROUND

Desmoid-type fibromatosis are rare intermediate tumors in children and adolescents. Owing to local aggressiveness and relapse, systemic treatment for symptomatic advanced or progressive forms is recommended. Following promising results in adult patients, oral vinorelbine is investigated in young patients.

METHODS

A retrospective review of young patients (<25 years old) with advanced or progressive desmoid type fibromatosis treated with oral vinorelbine in eight large centers of the Société Française des Cancers de l'Enfant was performed. In addition to tumor assessment according to RECIST 1.1, pre-treatment and during-treatment imagery were reviewed centrally to assess tumor volume and estimate fibrosis score through the change in percentage in hypoT2 signal intensity.

RESULTS

From 2005 to 2020, 24 patients (median age 13.9 years [range, 1.0-23.0]) received oral vinorelbine. Median number of prior systemic lines of treatment was 1 (range, 0-2), mainly based on intravenous low dose methotrexate and vinblastine. Before vinorelbine initiation, all patients had a progressive disease: radiological for 19, radiological and clinical (pain) for three and only clinical for two. Oral vinorelbine was delivered for a median duration of 12 months (range, 1-42). The toxicity profile was favorable, with no grade 3-4 event. Overall response estimated on 23 evaluable patients according to RECIST 1.1 criteria was three partial responses (13%), 18 stabilization (78%) and two progressive disease (9%). Overall progression-free survival was 89.3% (95% confidential intervals 75.2-100) at 24 months. Four stable tumors according to standard RECIST criteria displayed a partial response with > 65% tumor volume reduction. Among 21 informative patients, the estimated fibrosis score decreased for 15 patients, was stable for four patients and increased for two patients.

CONCLUSION

Oral vinorelbine seems to be effective to control advanced or progressive desmoid type fibromatosis in young patients, with a well-tolerated profile. These results support testing this drug as first-line alone or in combination to improve response rate while preserving quality of life.

A Pilot Study of Intralesional Injection of Triamcinolone Acetonide for Desmoid Tumors: Two-Year Outcomes

PURPOSE

The purpose of this pilot study was to examine the clinical efficacy and safety of serial triamcinolone injections for the treatment of desmoid tumors.

PATIENTS AND METHODS

Nine patients were enrolled into this prospective study and underwent three serial ultrasound-guided triamcinolone injections (120 mg) at 6-week intervals. MRI was compared at baseline and every 6 months, out to 24 months. Safety and tolerability were assessed by clinical evaluation and questionnaires, including the 12-item short form survey (SF-12), visual analog scale (VAS), and desmoid patient-reported outcome (PRO) tool.

RESULTS

At 24 months, 8 (88.9%) patients demonstrated a reduction in the volume of their tumor while 1 (11.1%) enlarged. Median tumor volume change was -26.9% (-81.1% to 34.6%; P = 0.055) All 9 tumors remained stable based on World Health Organization criteria, whereas 2 (22.2%) demonstrated partial response based on RECIST. There was a significant decrease in the tumor:muscle postcontrast mean signal intensity ratio at 6 months (P = 0.008) and 24 months (P = 0.004). There was a similar decrease in the tumor:muscle T2 mean signal intensity ratio at 24 months (P = 0.02). We found no difference in the SF-12 and VAS scores, but there were significant improvements in the desmoid PRO.

CONCLUSIONS

Treatment of desmoid tumors with serial triamcinolone injections appears safe and well tolerated by patients, with a 22% partial response based on RECIST. Further research is needed to confirm our results and determine factors predictive of response.

Selective Intra-Arterial Doxorubicin Eluting Microsphere Embolization for Desmoid Fibromatosis: A Combined Prospective and Retrospective Study

Simple Summary

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic treatment with doxorubicin is effective, but associated with significant toxicity. We investigated arterial doxorubicin eluting embolization (DEE), an approach that delivers high doxorubicin concentrations to the tumor with limited systemic drug exposure, in 24 patients (median age, 24 years; interquartile range, 16–34). Most patients (71%) had one or more than one prior DFs treatment (surgery, systemic therapy, or both). Patients underwent a median of two (range, 1–4) DEE treatments, with a median of 49 mg (range, 8–75) doxorubicin per treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. The procedure was safe and well tolerated.

Abstract

Desmoid fibromatoses (DFs) are locally aggressive tumors composed of monoclonal fibroblasts within an abundant extracellular matrix. Systemic doxorubicin treatment is effective, but toxic. We investigated arterial doxorubicin eluting embolization (DEE), an approach characterized by high drug concentrations in the tumor alongside limited systemic drug exposure. The primary and secondary endpoints were radiological response using MRI and RECIST 1.1, respectively. The study included 24 patients (median age, 24; interquartile range, 16–34 years). Data were collected prospectively for 9 patients and retrospectively for 15 patients. The most frequent tumor locations were chest/abdomen wall and neck/shoulder/axilla (29% each). Of 24 patients, 7 (24%) were treatment naïve, and 17 (71%) had received one or two prior treatments. Patients underwent a median of two treatments (range, 1–4), with a median of 49 mg (range, 8–75) doxorubicin/treatment. Efficacy outcomes were available for 23 patients. With a median follow-up of 8 months (interquartile range, 3–13), median tumor volumes decreased by 59% (interquartile range, 40–71%) and T2 signal intensity decreased by 36% (interquartile range, 19–55%). Of 23 patients, 9 (39%), 12 (52%), and 2 (9%) had a partial response, stable disease, and progressive disease, respectively. DEE was safe and well tolerated, with one reported grade 3–4 adverse event (cord injury). In conclusion, DEE was safe and achieved rapid clinical/volumetric responses in DFs.

Systemic Chemotherapies Retain Antitumor Activity in Desmoid Tumors Independent of Specific Mutations in CTNNB1 or APC: A Multi-institutional Retrospective Study

PURPOSE

Determine whether specific CTNNB1 or APC mutations in patients with desmoid tumor were associated with differences in clinical responses to systemic treatments.

EXPERIMENTAL DESIGN

We established a multi-institutional dataset of previously treated patients with desmoid tumor across four U.S. sarcoma centers, including demographic and clinicopathologic characteristics, treatment regimens, and clinical and radiographic responses. CTNNB1 or APC mutation status was determined from prior pathology records, or archival tissue was requested and analyzed by Sanger sequencing and/or next-generation sequencing. Evaluable patients with mutation results were analyzed to determine clinical progression-free survival (cPFS), RECIST 1.1 PFS (rPFS), time to next treatment (TTNT), and overall survival (OS). Kaplan-Meier analysis and Cox proportional hazards regression were performed to identify differences in cPFS, rPFS, TTNT, and OS by mutation subtype, desmoid tumor location, and treatment regimen.

RESULTS

A total of 259 evaluable patients were analyzed for at least one of the survival outcomes, with 177 patients having mutation data. First- and second-line cPFS, rPFS, and TTNT were not significantly affected by mutation subtype; however, APC-mutant desmoid tumors demonstrated nonstatistically significant inferior outcomes. Extremity/trunk desmoid tumor location and treatment with doxorubicin-based, methotrexate/vinca alkaloids and sorafenib regimens were associated with better clinical outcomes compared with surgery or "other" therapies, including estrogen-receptor blockade and imatinib. OS was significantly worse with APC or CTNNB1 negative/other mutations.

CONCLUSIONS

Mutation subtype did not affect responses to specific systemic therapies. APC mutations and nonextremity desmoid tumor locations remain prognostic for worse outcomes, and earlier initiation of systemic therapy for these higher-risk desmoid tumors should be prospectively evaluated. See related commentary by Greene and Van Tine, p. 3911.

The Role of Pharmacotherapeutic Agents in Children with Desmoid Tumors

Desmoid tumors (DT) are rare fibroblastic, soft-tissue tumors that do not metastasize but can aggressively infiltrate tissues causing significant chronic discomfort and/or functional impairment. In the pediatric population, the incidence of DT is greatest during infancy and adolescence but can occur at any age. Dysregulated β-catenin, most commonly resulting from mutations in either CTNNB1 or germline APC (adenomatous polyposis coli) drives DT. Most cases are sporadic but some are associated with predisposition syndromes such as familial adenomatous polyposis (FAP). Historically, treatment has been surgery. However, the recurrence rate after surgery can be high. Various systemic cytotoxic chemotherapy regimens used in other soft-tissue sarcomas have been applied to DT with differing results. Given the chronic and rarely life-threatening nature of this disease and the potential short- and long-term toxicity of these regimens, especially in children, alternative non-cytotoxic interventions have been investigated. Molecularly targeted agents such as tyrosine kinase and gamma secretase inhibitors have shown activity against DT. Innovative local control therapies are being employed as alternatives to surgery and radiation. Periods of prolonged stability and spontaneous regression in the absence of therapy in some patients has prompted wider adoption of an upfront active surveillance approach in the appropriate setting. This review will briefly summarize the epidemiology, pathophysiology, and clinical presentation of DT in children, then focus on historical, current, and future pharmacotherapeutic management and finally, propose areas for future study.

Desmoid tumors: who, when and how to treat?

PURPOSE OF REVIEW

The objective of this article is to summarize new treatment strategies of desmoid tumors.

RECENT FINDINGS

Desmoid tumor has an unpredictable evolution that may spontaneously regress or stabilize. A shift toward an initial frontline active surveillance has been acknowledged by experts. Surveillance monitoring should be performed frequently after the diagnosis to avoid missing a significant progression and then spaced in case of stabilization. Treatment is based on significant tumor growth or symptoms. Recent guidelines recommend commencing medical treatment. Kinase inhibitors and cytotoxic agents are the two classes of drugs where studies included progressive desmoid tumors and should be selected to guide medical practice. In a randomized trial, 2 years progression-free survival (PFS) was significantly better in the sorafenib group (81 versus 36% in the placebo group). In another randomized phase 2, 6 months PFS was 83.7% with pazopanib versus 45% with methotrexate and vinblastine. In a retrospective study, including progressive desmoid tumors, methotrexate + vinca alkaloids achieved 75 months median PFS. Cryotherapy is an alternative option in desmoid tumors with compatible locations and tumor sizes. Following medical treatment or cryotherapy failure, superficial sites represent the best indications for surgery in cases of continuous progression. In the event of a contra-indication or failure of medical treatment, in locations where surgery would be mutilating and incomplete, radiotherapy is an effective option.

SUMMARY

Active surveillance with planned imaging has become the first-line management in desmoid tumor.

Tenosynovial giant cell tumor-diffuse type, treated with a novel colony-stimulating factor inhibitor, pexidartinib: initial experience with MRI findings in three patients

Tenosynovial giant cell tumor-diffuse type (diffuse TSGCT) is a benign but locally aggressive proliferative disorder of the synovium. Treatment is usually surgical, although in cases of extensive disease complete synovectomy is not possible and local recurrence rates are high. Pexidartinib (trade name Turalio®), a colony-stimulating factor-1 (CSF-1) inhibitor, was shown in a recent phase III trial to effectively treat diffuse TSGCT and is FDA approved for the treatment of adult patients with symptomatic diffuse TSGCT associated with severe morbidity or functional limitations and not amenable to improvement with surgery. Pexidartinib is available only through a restricted program under a risk evaluation and mitigation strategy (REMS) because of the risk of hepatotoxicity. Magnetic resonance imaging (MRI) is the preferred imaging modality for the diagnosis and surveillance of TSGCT. Here we present three patients with diffuse TSGCT of the knee who underwent multiple MRIs over several years while on pexidartinib. We describe the disease burden and signal characteristics on MRI and correlate with the response reported in the patients' medical records. Given that the use of pexidartinib and other CSF inhibitors is likely to increase, musculoskeletal radiologists should be aware of this novel non-operative treatment and the MRI appearance of diffuse TSGCT during therapy.

Update of pediatric soft tissue tumors with review of conventional MRI appearance-part 1: tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors

There are numerous soft tissue tumors and tumor-like conditions in the pediatric population. Magnetic resonance imaging is the most useful modality for imaging these lesions. Although certain soft tissue lesions exhibit magnetic resonance features characteristic of a specific diagnosis, most lesions are indeterminate, and a biopsy is necessary for diagnosis. We provide a detailed update of soft tissue tumors and tumor-like conditions that occur in the pediatric population, emphasizing each lesion's conventional magnetic resonance imaging appearance, using the recently released 5th edition of the World Health Organization Classification of Soft Tissue and Bone Tumors as a guide. In part one of this review, pediatric tumor-like lesions, adipocytic tumors, fibroblastic and myofibroblastic tumors, and perivascular tumors are discussed. In part two, vascular lesions, fibrohistiocytic tumors, muscle tumors, peripheral nerve sheath tumors, tumors of uncertain differentiation, and undifferentiated small round cell sarcomas are reviewed. Per the convention of the WHO, these lesions involve the connective, subcutaneous, and other non-parenchymatous-organ soft tissues, as well as the peripheral and autonomic nervous system.

Pseudoaneurysm within a desmoid tumor in an extremity: report of 2 cases

Desmoid tumor is considered a benign neoplasm, yet substantial morbidity can result from local invasion of structures adjacent to the tumor or from complications related to its treatment. We report two patients with extremity desmoid tumor who were each found at MRI to have an unsuspected pseudoaneurysm within their tumor after prior treatments (surgery and systemic therapy in one, surgery alone in the other). Such a pseudoaneurysm probably results from weakening of an arterial wall by adjacent desmoid tumor, as well as from local trauma. Due to the potential risk for life-threatening rupture of a pseudoaneurysm, one patient underwent surgical repair and the other, coil embolization. To our knowledge the presence of pseudoaneurysm has been reported within a few cases of abdominal desmoid tumor but not within an extremity desmoid tumor. This diagnosis has not been reported to have been made at MRI, either.

Differential diagnosis of T2 hypointense masses in musculoskeletal MRI

Many soft tissue masses have an indeterminate appearance on MRI, often displaying varying degrees and extent of T2 hyperintensity. However, a subset of neoplasms and tumor-like lesions may exhibit prominent areas of T2 hypointensity relative to skeletal muscle. The hypointensity observed on T2-weighted MRI can be caused by a variety of substances, including evolving blood products, calcifications or other inorganic crystals, or fibrous tissue. Carefully evaluating the presence and pattern of T2 hypointensity in soft tissue masses and considering potential causes in their associated clinical contexts can help to narrow the differential diagnosis among neoplastic and non-neoplastic possibilities. These include endometriosis, aneurysmal bone cysts, tenosynovial giant cell tumor, arteriovenous malformation and pseudoaneurysm, calcium pyrophosphate and hydroxyapatite deposition diseases, tumoral calcinosis, gout, amyloidosis, hemangiomas with phleboliths, low-grade fibromyxoid sarcoma, ossifying fibromyxoid tumor, collagenous fibroma, desmoid-type fibromatosis, myxofibrosarcoma, peripheral nerve sheath tumors, dedifferentiated liposarcoma, and treated sarcoma.

Familial adenomatosis polyposis-related desmoid tumours treated with low-dose chemotherapy: results from an international, multi-institutional, retrospective analysis

Introduction

Desmoid tumour (DT) is a locally aggressive fibroblastic proliferative disease representing the most common extraintestinal manifestation of familial adenomatosis polyposis (FAP). As data on the activity of chemotherapy in these patients are limited, we examined the outcomes of patients treated with low-dose methotrexate (MTX)+vinca alkaloids (vinorelbine or vinblastine).

Patients and methods

We retrospectively reviewed clinical and outcome data from all patients with confirmed FAP-associated DTs treated with weekly MTX+vinca alkaloids in seven European sarcoma reference centres between January 2000 and December 2018. Radiological responses were assessed using RECIST V.1.0 and V.1.1. The Kaplan-Meier method associated to the log-rank test was used to estimate and compare survival curves.

Results

We identified 37 patients (median age 29 years, range 7–44). According to RECIST, 20/37 (54.1%) patients achieved partial response (PR), 15/37 (40.5%) patients had stable disease and 2/37 (5.4%) had progressive disease as best response. Overall, the median progression-free survival (PFS) was 6.5 years (range, 0.3–12.1 years). In the subset of patients achieving PR as best response, the median PFS was not reached. In a subset of 11 patients with progressive disease offered MTX+vinca alkaloids rechallenge (after chemotherapy withdrawal following prolonged disease control), the disease control rate was 100%, resulting in a median PFS after rechallenge of 5.8 years.

Conclusions

This is the largest series on the activity of low-dose chemotherapy in patients with FAP-related DT. In this population, MTX+vinca alkaloids is an active combination, as already reported in patients with sporadic DT.

MRI Volumetrics and Image Texture Analysis in Assessing Systemic Treatment Response in Extra-Abdominal Desmoid Fibromatosis

Purpose To determine whether MRI volumetric and image texture analysis correlates with treatment-induced biologic changes in desmoid fibromatosis (DF) earlier than conventional response criteria. Materials and Methods This retrospective study included 27 patients with histologically proven extra-abdominal DF who were managed with active surveillance or systemic therapy (from 2004 to 2016). MRI volumetric and image texture parameters were derived from manual tumor segmentations, and tumor signal intensity was normalized to muscle. Results were compared with objective response rates based on Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1, World Health Organization (WHO) lesion response, volumetrics, and MRI-modified Choi criteria. Correlation coefficients (r) between image texture features and maximum tumor diameters were obtained by using a meta-analysis approach. Results The 27 included patients (mean age, 39 years; 74% women) were followed for an average of 4 years, comprising 207 distinct time-point assessments. The mean baseline tumor maximum diameter was 7.9 cm (range, 3.4-15.2 cm). Partial response (PR) rates as best response were 37%, 44%, 70%, and 81% by RECIST, WHO, volumetrics, and MRI-modified Choi criteria, respectively. Among the 10 tumors showing RECIST PR, a preceding MRI-modified Choi PR was observed in 70% (seven of 10), on average 1.3 years earlier. Multiple image texture parameters showed associations with objective measurements of tumor diameter including mean tumor-to-muscle signal ratio (r = 0.51; P = .004), median tumor-to-muscle signal ratio (r = 0.52; P = .003), energy (r = 0.48; P < .001), run entropy (r = 0.32, P = .04), and gray-level nonuniformity (r = 0.54; P ≤ .001). Conclusion Volumetric signal and image texture assessment allows more comprehensive analysis of DF biologic change and may permit early prediction of DF behavior and therapeutic response. Keywords: MR Imaging, Soft Tissues/Skin, Neoplasms-Primary © RSNA, 2021.

Superficial fibromatosis: MRI radiomics and T2 mapping correlate with treatment response

BACKGROUND

Superficial fibromatosis exhibits variable MR signal intensity due to collagenous and fibroproliferative components. Quantifying this signal heterogeneity using image texture analysis and T2-mapping could have prognostic and therapeutic implications.

METHODS

This IRB-approved retrospective study included 13 patients with superficial fibromatosis, managed by observation, electron beam radiotherapy (EBT), or pentoxifylline/vitamin E. Two-dimensional regions of interest (ROIs) were drawn on proton-density or T2-weighted MRI for radiomics feature analysis, and corresponding T2-maps. Comparisons were made between baseline and follow-up T2 relaxation times and radiomics features: Shannon's entropy, kurtosis, skewness, mean of positive pixels (MPP), and uniformity of distribution of positive gray-level pixel values (UPP).

RESULTS

There were 19 nodules in 13 subjects. Mean patient age was 60 years; 62% (8/13) were female; mean follow-up was 9.7 months. Nodule diameter at baseline averaged 18.2 mm (std dev 16.2 mm) and decreased almost 10% to 16.6 mm (p = 0.1, paired t-test). Normalized T2 signal intensity decreased 23% from 0.71 to 0.55 (p = 0.03, paired t-test). T2 relaxation time decreased 16% from 46.5 to 39.1 ms (p < 0.001, paired t-test). Among radiomics features, skewness increased to 0.71 from 0.41 (p = 0.03, paired t-test), and entropy decreased from 8.37 to 8.03 (p = 0.05, paired t-test); differences in other radiomics features were not significant.

CONCLUSIONS

Radiomics analysis and T2-mapping of superficial fibromatosis is feasible; robust decreases in absolute T2 relaxation time, and changes in image textural features (increased skewness and decreased entropy) offer novel imaging biomarkers of nodule collagenization and maturation.

Rationale for the use of tyrosine kinase inhibitors in the treatment of paediatric desmoid-type fibromatosis

In children with desmoid-type fibromatosis (DTF) in whom disease progression occurs after an initial watch-and-wait strategy, prolonged low-dose chemotherapy using vinblastine and methotrexate (VBL-MTX) is currently the standard of care. These conventional drugs have been prospectively evaluated but their efficacy and safety profiles are limited, and alternative therapeutic options are therefore essential. Based on the results of clinical trials, the use of tyrosine kinase inhibitors (TKIs) in the treatment of DTF is currently considered only in adult patients. TKIs such as imatinib show superior therapeutic efficacy to VBL-MTX and tolerable short-term side effects for the treatment of adult DFT, supporting the concept of the use of TKIs for the treatment of paediatric DFT. Moreover, new-generation TKIs, such as pazopanib and sorafenib, have shown improved therapeutic efficacy compared to imatinib in adult non-comparative studies. A tolerable safety profile of TKI therapy in children with disease entities other than DTF, such as leukaemia, has been reported. However, the efficacy and, in particular, the long-term safety of TKIs, including childhood-specific aspects such as growth and fertility, for the treatment of children with DTF should be investigated prospectively, as DFT therapy requires long-term drug exposure.

Percutaneous Microwave Ablation of Desmoid Fibromatosis

Objective

To demonstrate the feasibility of percutaneous microwave ablation in desmoid fibromatosis with respect to tumor volume control and improvement in the quality of life.

Materials and Methods

Twelve microwave ablations were performed in 9 patients with a histological diagnosis of desmoid fibromatosis between January 2010 and January 2019. The study population included 6 female and 3 male, with an age range of 21–76 years (mean = 46.6 years; standard deviation [SD] = 19.3 years). The mean major axis of the tumors was 10.9 cm (SD = 5.2 cm) and mean lesion volume was 212.7 cm³ (SD = 213 cm³). Their anatomical distribution was as follows: 3 lesions in the thigh, 2 in the gluteus, 2 in the leg and 2 in the periscapular region. We evaluated the reduction in tumor volume and improvement in the quality of life based on the Eastern Cooperative Oncology Group (ECOG) scale.

Results

An average tumor volume reduction of 70.4% (SD = 24.9) was achieved, while the quality of life (ECOG scale) improved in 88.9% of patients.

Conclusion

Percutaneous microwave ablation may potentially be a safe, effective, and promising technique for controlling tumor volume and improving the quality of life in patients with desmoid fibromatosis.

MRI T1 Contrast-Enhanced Signal Intensity Is a Prognostic Indicator of Imatinib Therapy in Desmoid-Type Fibromatosis

Objective

To investigate the efficiency of pre-therapy magnetic resonance imaging (MRI) features in predicting the prognosis of desmoid-type fibromatosis patients treated with imatinib.

Materials and Methods

A total of 38 desmoid-type fibromatosis patients treated with imatinib were collected in this retrospective study. The high signal intensity on pre-therapy MRI was evaluated on axial T2 and T1 contrast-enhanced sequences with fat suppression. Cox regression and Kaplan-Meier analyses explored the correlation between clinical or radiographic characteristics and progression-free survival (PFS).

Results

Hyperintense T1 contrast enhancement (CE) proportion (≥ 75%) was identified as an independent predictor for PFS. Patients with hyperintense T1 CE proportion <75% demonstrated no progression, while patients with hyperintense T1 CE proportion ≥75% demonstrated a progression rate of 78.4%.

Conclusion

Hyperintense T1 CE proportion in the tumor is a potential predictor of disease progression in patients with desmoid-type fibromatosis treated with imatinib. Hyperintense T1 CE proportion <75% indicates progression-free during treatment.

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.

Long-term diagnostic value of MRI in detecting recurrent aggressive fibromatosis at two multidisciplinary sarcoma centers

PURPOSE

To assess the diagnostic accuracy of MRI in detecting recurrent aggressive fibromatosis (AF) during long-term follow-up at two multidisciplinary sarcoma centers.

METHODS

Seventy-nine patients from two sarcoma centers were included in this IRB-approved study and were examined postoperatively using 1.5-T MRI. MRI follow-up scans were reviewed for true-positive/-negative and false-positive/-negative results. Available pathological reports and MRI follow-ups were set as reference.

RESULTS

The median age of the patients was 38.1 ± 15.3 years. Of the patients 27.9 % showed recurrent AF lesions. The most common localizations of AF were the axilla/shoulder (n = 15) and the thigh (n = 11). From 498 postoperative MRI follow-ups, 24 true-positive, 16 false-positive, 6 false-negative, and 452 true-negative MRI follow-ups were identified. The overall sensitivity and specificity for detecting recurrent AF was 80 % and 97 %, respectively. There was no significant difference in the diagnostic accuracy at the two sarcoma centers. All false-negative results were found in small lesions. False-positive results mostly mimicked streaky (n = 10) and small ovoid/nodular (n = 5) lesions. The configuration of recurrent AF was significantly most often fascicular (50 %; p = 0.001-0.005).

CONCLUSION

MRI shows a high long-term diagnostic value in detecting AF recurrences. Nevertheless, radiologists should pay close attention when lesions are small, as they may remain undetected. Although the configuration of recurrent AF is most often fascicular, recurrences may also appear in different shapes.

Progressive Desmoid Tumor: Radiomics Compared With Conventional Response Criteria for Predicting Progression During Systemic Therapy-A Multicenter Study by the French Sarcoma Group

OBJECTIVE. 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. MATERIALS AND METHODS. 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 β-catenin mutation. RESULTS. 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). CONCLUSION. Quantifying early changes in heterogeneity through a dedicated radiomics score could improve response evaluation for patients with DT undergoing chemotherapy.

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.

Differential diagnosis and mutation stratification of desmoid-type fibromatosis on MRI using radiomics

PURPOSE

Diagnosing desmoid-type fibromatosis (DTF) requires an invasive tissue biopsy with β-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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Desmoid-type fibromatosis of the lower extremity: A unique case of complete lesion resolution following core needle biopsy

Desmoid-type fibromatosis (DF) is a rare neoplasm characterized by fibroblastic and myofibroblastic proliferation. While characterized as a benign lesion that does not metastasize, desmoid-type fibromatosis exhibits a wide range of behavior from aggressive local tissue invasion and post-surgical recurrence to spontaneous regression. Tumor regression can occur following systemic medical therapy or rarely may occur in the absence of therapy. We present a case of a 50-year-old female with a left thigh vastus medialis intramuscular mass which underwent imaging work-up and subsequent core needle ultrasound-guided biopsy showing results of desmoid-type fibromatosis. Following biopsy, the tumor showed prompt, complete regression with complete MRI resolution 2 months following biopsy. The patient showed no evidence of disease recurrence out to one year on MRI surveillance. This case report will discuss desmoid-type fibromatosis imaging features, treatment strategies, spectrum of disease behavior, and atypical behavior such as the spontaneous tumor regression as seen in this case report. To our knowledge there have been no reported cases of DF spontaneous regression 2 months following a core needle biopsy. Understanding the variable behavior of desmoid-type fibromatosis can assist the radiologist in guiding management of these lesions with the goal of optimizing clinical outcomes and preventing unnecessary aggressive treatments for stable or regressing disease.

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.

[Magnetic resonance imaging of desmoid-type fibromatosis: Current evaluation criteria]

The management of desmoid-type fibromatosis has considerably evolved these last years, toward first-line active surveillance then systemic or local symptomatic treatment in case of aggressive tumor. Magnetic resonance imaging is the modality of choice in each of these treatment settings. It needs multiparametric approach taking into account mainly the tumor size, and T2-weighted signal that is correlated with histological composition and clinical behavior. A volumetric approach should be favored for the evaluation of tumor size change. The interest of paramagnetic contrast injection and tumor enhancement requires further investigation.

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

OBJECTIVES

To propose a follow-up strategy for desmoid-type fibromatosis (DF) based on tumor growth behavior and the signal on T2-weighted MRI.

METHODS

We retrospectively reviewed 296 MRI studies of 34 patients with histologically proven DF. In each study, tumor volume and T2 signal relatively normal striated muscle were assessed. Volume variation and monthly growth rates were analyzed to determine lesion growth behavior (progressing versus stable/regressing lesions). Growth behavior was correlated with T2 signal, tumor location, β-catenin status, treatment strategy, and follow-up duration. Interobserver variability of volume measurements and interobserver measurement variation ratio were assessed.

RESULTS

There were 25 women and 9 men with a mean age of 39.9 ± 19 (4-73) years. Mean follow-up time in the patients included was 55 ± 41 (12-148) months. In progressing lesions, the mean average monthly growth ratio was 10.9 ± 9.2 (1.1-42.5) %. Interobserver variability of volume measurements was excellent (ICC = 0.96). Mean interobserver measurement variation ratio was 20.4 ± 23.6%. The only factor correlated with tumor growth behavior was T2 signal ratio (p < 0.0001). Seventeen out of 34 (50%) patients presented a signal change over the threshold of 1 during follow-up. There were five occurrences of secondary growth after a period of stability with a mean delay until growth of 38.2 ± 44.2 (17-116) months.

CONCLUSION

DF growth rate was quantitatively assessed. A threshold for volume variation detection was established. DF growth behavior was significantly related to T2 signal. An evidence-based follow-up strategy is proposed.

KEY POINTS

• In progressing desmoid fibromatosis, the mean average monthly growth ratio was 10.9 ± 9.2%. • Lesions with muscle/tumor T2 signal ratios lower than 1 tended to be stable or regress over time. • Given the interobserver measurement variability and MRI in-plane spatial resolution, a variation higher than 42.6% in tumor volume is required to confirm punctual progression.

MRI characteristics predict the efficacy of meloxicam treatment in patients with desmoid-type fibromatosis

INTRODUCTION

This study aimed to determine the clinical significance of MRI characteristics as a possible predictor of responsiveness to meloxicam treatment in patients with desmoid-type fibromatosis (DF). Additionally, it analysed the correlation between CTNNB1 mutation status and signal intensity of MRI.

METHODS

Forty-six patients consecutively treated with meloxicam composed this study. The low-intensity area (LIA) on T2-weighted MRI was determined. We divided patients into two groups based on the efficacy of meloxicam: a clinical benefit group (CB group, including CR: complete response; PR: partial response; and SD: stable disease) and non-clinical benefit group (NB group, including PD: progressive disease). Correlations of the efficacy with LIA and CTNNB1 mutation status with LIA were investigated.

RESULTS

In total, 11, 17 and 18 patients showed PR, SD and PD, respectively. The mean LIA ratio before treatment was significantly higher (P < 0.001) in the CB group than in the NB group. For predicting the efficacy, sensitivity was 68%, and specificity was 89% when setting the cut-off value as 20% for LIA. Mean changes in the LIA ratio before and after treatment were significantly higher (P = 0.01) in the CB group than in the NB group. Mean LIA ratio before treatment was significantly lower (P < 0.001) in the S45F mutation group than in the other mutation group. In multivariate analysis, the LIA ratio before treatment was a significant predictor of responsiveness (P = 0.02).

CONCLUSIONS

MRI characteristics were a useful predictor of the efficacy of meloxicam in DF patients. It may be possible to predict the clinical outcome more accurately when combined with other factors, such as CTNNB1 mutantion status.

Clinical benefit of methotrexate plus vinorelbine chemotherapy for desmoid fibromatosis (DF) and correlation of treatment response with MRI

Background

Desmoid fibromatosis (DF) is a rare fibroblastic proliferation that was historically treated with surgery. We report (a) outcomes using low‐dose chemotherapy, methotrexate (MTX), and vinorelbine (VNL) for patients with progressing disease (PD) and (b) whether tumor volume (V_tumor) and T2 signal on magnetic resonance imaging (MRI) are more reflective of treatment response compared with maximum tumor dimension (D_max) defined by RECIST1.1.

Methods

Patients with biopsy‐proven DF, treated with MTX/VNL from 1997 to 2015 were reviewed. MRI for a subset of patients was independently re‐evaluated for response by RECIST, V_tumor, and quantitative T2 hyperintensity.

Results

Among 48 patients treated for a median 19 months MTX/VNL, only nine (19%) had previous surgery. RECIST‐based overall response rate was complete response (CR) 20 (42%) + partial response (PR) 19 (39%), stable disease (SD) 8 (17%), for a clinical benefit rate of 98%. The median progression‐free survival (PFS) was 120 months, (95%CI 84‐155 months). Thirty‐six (75%) patients had not progressed at a median 38 months from treatment completion. Most common grade 1/2 toxicities included nausea (n = 12, 25%) and fatigue (n = 9,19%) with no grade 3/4 toxicities. In 22 patients with serial MRIs, there was a decrease in D_max mean by 30%, V_tumor by 76%, and in 19/22 (86%) a decrease in T2 signal intensity.

Conclusion

Low‐dose MTX/VNL for a defined duration has high efficacy with sustained benefit and minimal toxicity for treating DF. V_tumor and T2 signal might better predict treatment response than RECIST.

Doxorubicin-Eluting Intra-Arterial Therapy for Pediatric Extra-Abdominal Desmoid Fibromatoses: A Promising Approach for a Perplexing Disease

Systemic doxorubicin is effective for desmoid fibromatosis (DF), but its use is limited by dose-dependent cardiotoxicity. A protocol of selective intra-arterial doxorubicin drug-eluting embolization (DEE) was designed to maximize target tissue efficacy of doxorubicin, while minimizing systemic exposure. Four children with recurrent or refractory DF were treated between 2014 and 2017. Tumor volumes were reduced by 54%-97% over a follow-up interval of 6-32 months. A single patient experienced transient lower extremity paresthesia (Common Terminology Criteria for Adverse Events grade I). Further investigation is needed to better establish these promising results for doxorubicin DEE in DF treatment.

Aggressive fibromatosis response to tamoxifen: lack of correlation between MRI and symptomatic response

Background

One of the commonly used systemic agents for the treatment of aggressive fibromatosis is the anti-oestrogen drug tamoxifen. However, data on efficacy and optimum methods of response assessment are limited, consisting mainly of small case series and reports.

Methods

A retrospective database was used to identify consecutive patients diagnosed with aggressive fibromatosis (AF) and treated with tamoxifen plus/minus non-steroidal anti-inflammatory drugs at our tertiary referral centre between 2007 and 2014. MRI and symptom changes were recorded.

Results

Thirty-two patients (13 male 19 female, median age 41 years) were included. Median duration of treatment with tamoxifen was 316 days. Of 9 patients with progressive disease by RECIST 1.1 (28%): 4 patients experienced worsening symptoms; 3 patients had improved symptoms and 2 had no change in symptoms. Of 22 patients with stable disease (69%): 11 had no change in symptoms; 6 had improved symptoms and 5 patients had worsening symptoms. One patient achieved a partial response with improved symptoms.

Conclusions

No relationship was identified between symptomatic benefit and response by RECIST 1.1 on MRI. Prospective studies in AF should incorporate endpoints focusing on patient symptoms.

T2 signal intensity as an imaging biomarker for patients with superficial Fibromatoses of the hands (Dupuytren's disease) and feet (Ledderhose disease) undergoing definitive electron beam irradiation

OBJECTIVE

Electron beam therapy is a definitive radiation treatment option for superficial fibromatoses of the hands and feet. Because objective criteria for treatment response remain poorly defined, we sought to describe changes in electron beam treated lesions on MRI.

MATERIALS AND METHODS

The study included 1 male and 9 female patients with a total of 37 superficial fibromatoses; average age was 60.7 years. Standard 6 MeV electron beam treatment included 3 Gy per fraction for 10 or 12 treatments using split-course with 3-month halfway break. Pre- and post-treatment MRIs were evaluated to determine lesion size (cm3), T2 signal intensity and contrast enhancement (5-point ordinal scales) by a fellowship trained musculoskeletal radiologist. MRI findings were correlated with clinical response using a composite 1-5 ordinal scale, Karnofsky Performance Scale and patient-reported 10-point visual analog scale for pain.

RESULTS

Mean volume decreased from 1.5 to 1.2 cm³ (p = 0.01, paired t-test). Mean T2 hyperintensity score decreased from 3.0 to 2.1 (p < 0.0001, Wilcoxon signed-rank). Mean enhancement score available for 22 lesions decreased from 3.8 to 3.0 (p < 0.0001, Wilcoxon signed-rank). Performance scores improved from 78.9 ± 13.7 to 84.6 ± 6.9 (p = 0.007, paired t-test). Pain scores decreased from 3.0 ± 3.3 to 1.1 ± 2.0 (p = 0.0001, paired t-test). Post-treatment T2 signal correlated weakly with performance and pain (Spearman's ρ = -0.37 and 0.16, respectively).

CONCLUSIONS

MRI is valuable for evaluating patients undergoing electron beam therapy for superficial fibromatoses: higher pretreatment T2 intensity may predict benefit from radiotherapy. T2 hypointensity may be a better marker than size for therapeutic effect.

Long-Term Follow-Up of Desmoid Fibromatosis Treated with PF-03084014, an Oral Gamma Secretase Inhibitor

BACKGROUND

Desmoid fibromatosis is a fibroblastic neoplasm driven by aberrations within the WNT pathway, exhibiting mutations in β-catenin or APC. We review the long-term follow-up of patients in a phase I study treated with an oral gamma secretase inhibitor, PF-03084014.

METHODS

PF-03084014 was administered orally at doses ranging from 20 to 330 mg twice daily. Tumor assessments were performed using computed tomography/magnetic resonance imaging (CT/MRI) within 4 weeks of study entry, and every other cycle through cycle 9. After cycle 9, patients were evaluated as clinically indicated.

RESULTS

Seven patients with desmoid fibromatosis were treated between December 2009 and December 2016 at the University of Colorado. Five patients (71.4%, 95% confidence interval [CI] 29.0-96.3%) achieved a partial response (PR), with a mean time to achieving response of 11.9 months (95% CI 2.5-21.4 months). All patients who achieved a PR continue to maintain responses between 47.9 and 73+ months. Four patients stopped treatment yet remain free of progression between 11 and 53+ months. One patient had PFS of 42+ months, with a 17% decrease in the target lesion. A biopsy performed at the end of the study showed decreased tumoral cellularity compared with previous biopsies. Effective treatment doses ranged from 80 to 330 mg administered orally twice daily.

CONCLUSIONS

PF-03084014 was effective in treating desmoid tumors, with an objective response rate of 71.4% (95% CI 29.0-96.3%) in this small cohort of patients. PF-03084014 exhibits promising activity, even at relatively low doses (80 mg twice daily), with high tolerability leading to prolonged disease control even after therapy discontinuation.

Duodenum-derived fibromatosis that invaded the muscular layer of intestinal wall: A rare case report

RATIONALE

Intraabdominal fibromatosis is a rare benign tumor that often affects the mesentery or retroperitoneum, and can infiltrate adjacent organs. However, it is rare for fibromatosis to arise from the small intestinal wall.

PATIENT CONCERNS

A 27-year-old female with a tangible abdominal tumor is described.

DIAGNOSES

The computed tomography (CT) scan revealed a 7.5 cm, small intestine-associated tumor in the right abdomen.

INTERVENTIONS

The patient received tumor resection and intestinal anastomosis.

OUTCOMES

Further pathological examination confirmed the tumor as a duodenal fibromatosis that infiltrated the intestinal wall. To the best of our knowledge, this is the first report of a duodenum-derived fibromatosis that invaded the muscular layer of the intestine.

LESSONS

Our study demonstrated that an unexplained abdominal mass should be noteworthy and properly treated.

Clinical Activity of the γ-Secretase Inhibitor PF-03084014 in Adults With Desmoid Tumors (Aggressive Fibromatosis)

Purpose Desmoid tumors (aggressive fibromatosis) arise from connective tissue cells or fibroblasts. In general, they are slow growing and do not metastasize; however, locally aggressive desmoid tumors can cause severe morbidity and loss of function. Disease recurrence after surgery and/or radiation and diagnosis of multifocal desmoid tumors highlight the need to develop effective systemic treatments for this disease. In this study, we evaluate objective response rate after therapy with the γ-secretase inhibitor PF-03084014 in patients with recurrent, refractory, progressive desmoid tumors. Patients and Methods Seventeen patients with desmoid tumors received PF-03084014 150 mg orally twice a day in 3-week cycles. Response to treatment was evaluated at cycle 1 and every six cycles, that is, 18 weeks, by RECIST (Response Evaluation Criteria in Solid Tumors) version 1.1. Patient-reported outcomes were measured at baseline and at every restaging visit by using the MD Anderson Symptoms Inventory. Archival tumor and blood samples were genotyped for somatic and germline mutations in APC and CTNNB1. Results Of 17 patients accrued to the study, 15 had mutations in APC or CTNNB1 genes. Sixteen patients (94%) were evaluable for response; five (29%) experienced a confirmed partial response and have been on study for more than 2 years. Another five patients with prolonged stable disease as their best response remain on study. Patient-reported outcomes confirmed clinician reporting that the investigational agent was well tolerated and, in subgroup analyses, participants who demonstrated partial response also experienced clinically meaningful and statistically significant improvements in symptom burden. Conclusion PF-03084014 was well tolerated and demonstrated promising clinical benefit in patients with refractory, progressive desmoid tumors who receive long-term treatment.