A Timely Oral Option: Single-Agent Vinorelbine in Desmoid Tumors

UK guidelines for the management of soft tissue sarcomas

Soft tissue sarcomas (STS) are rare tumours arising in mesenchymal tissues and can occur almost anywhere in the body. Their rarity, and the heterogeneity of subtype and location, means that developing evidence-based guidelines is complicated by the limitations of the data available. This makes it more important that STS are managed by expert multidisciplinary teams, to ensure consistent and optimal treatment, recruitment to clinical trials, and the ongoing accumulation of further data and knowledge. The development of appropriate guidance, by an experienced panel referring to the evidence available, is therefore a useful foundation on which to build progress in the field. These guidelines are an update of the previous versions published in 2010 and 2016 [1, 2]. The original guidelines were drawn up by a panel of UK sarcoma specialists convened under the auspices of the British Sarcoma Group (BSG) and were intended to provide a framework for the multidisciplinary care of patients with soft tissue sarcomas. This iteration of the guidance, as well as updating the general multidisciplinary management of soft tissue sarcoma, includes specific sections relating to the management of sarcomas at defined anatomical sites: gynaecological sarcomas, retroperitoneal sarcomas, breast sarcomas, and skin sarcomas. These are generally managed collaboratively by site specific multidisciplinary teams linked to the regional sarcoma specialist team, as stipulated in the recently published sarcoma service specification [3]. In the UK, any patient with a suspected soft tissue sarcoma should be referred to a specialist regional soft tissues sarcoma service, to be managed by a specialist sarcoma multidisciplinary team. Once the diagnosis has been confirmed using appropriate imaging and a tissue biopsy, the main modality of management is usually surgical excision performed by a specialist surgeon, combined with pre- or post-operative radiotherapy for tumours at higher risk for local recurrence. Systemic anti-cancer therapy (SACT) may be utilised in cases where the histological subtype is considered more sensitive to systemic treatment. Regular follow-up is recommended to assess local control, development of metastatic disease, and any late effects of treatment.

Current therapies and future prospective for locally aggressive mesenchymal tumors

Locally aggressive mesenchymal tumors comprise a heterogeneous group of soft tissue and bone tumors with intermediate histology, incompletely understood biology, and highly variable natural history. Despite having a limited to absent ability to metastasize and excellent survival prognosis, locally aggressive mesenchymal tumors can be symptomatic, require prolonged and repeat treatments including surgery and chemotherapy, and can severely impact patients' quality of life. The management of locally aggressive tumors has evolved over the years with a focus on minimizing morbid treatments. Extensive oncologic surgeries and radiation are pillars of care for high grade sarcomas, however, play a more limited role in management of locally aggressive mesenchymal tumors, due to propensity for local recurrence despite resection, and the risk of transformation to a higher-grade entity following radiation. Patients should ideally be evaluated in specialized sarcoma centers that can coordinate complex multimodal decision-making, taking into consideration the individual patient's clinical presentation and history, as well as any available prognostic factors into customizing therapy. In this review, we aim to discuss the biology, clinical management, and future treatment frontiers for three representative locally aggressive mesenchymal tumors: desmoid-type fibromatosis (DF), tenosynovial giant cell tumor (TSGCT) and giant cell tumor of bone (GCTB). These entities challenge clinicians with their unpredictable behavior and responses to treatment, and still lack a well-defined standard of care despite recent progress with newly approved or promising experimental drugs.

Clinical outcomes of medical treatments for progressive desmoid tumors following active surveillance: a systematic review

Approximately 80% of desmoid tumors (DTs) show spontaneous regression or disease stabilization during first-line active surveillance. Medical treatment can be considered in cases of disease progression. This systematic review aimed to evaluate the effectiveness and toxicity of each medical treatment by reviewing only the studies that included progressive disease as the inclusion criterion. We searched the EMBASE, PubMed, and CENTRAL databases to identify published studies for progressive DTs. The disease control rates of the medical treatments, such as low-dose chemotherapy with methotrexate plus vinblastine or vinorelbine, imatinib, sorafenib, pazopanib, nilotinib, anlotinib, doxorubicin-based agents, liposomal doxorubicin, hydroxyurea, and oral vinorelbine for progressive DTs were 71-100%, 78-92%, 67-96%, 84%, 88%, 86%, 89-100%, 90-100%, 75%, and 64%, respectively. Low-dose chemotherapy, sorafenib, pazopanib, nilotinib, anlotinib, and liposomal doxorubicin had similar toxicities. Sorafenib and pazopanib were less toxic than imatinib. Doxorubicin-based chemotherapy was associated with the highest toxicity. Hydroxyurea and oral vinorelbine exhibited the lowest toxicity. Stepwise therapy escalation from an initial, less toxic treatment to more toxic agents is recommended for progressive DTs. Sorafenib and pazopanib had limited on-treatment side effects but had the possibility to induce long-term treatment-related side effects. In contrast, low-dose chemotherapy has some on-treatment side effects and is known to have very low long-term toxicity. Thus, for progressive DTs following active surveillance, low-dose chemotherapy is recommended in young patients as long-term side effects are minor, whereas therapies such as sorafenib and pazopanib is recommended for older patients as early side effects are minor.

Pregnancy-associated desmoid fibromatosis: A Dutch multi-centre retrospective study

INTRODUCTION

The development of desmoid fibromatosis (DF) is associated with pregnancy. The current treatment consensus recommends active surveillance (AS). However, data in pregnancy-associated DF is scarce and it is uncertain whether AS is the best management strategy for this DF-subgroup. The aim of this study was to describe demographic, tumor, obstetric, treatment characteristics and treatment outcome in pregnancy-associated DF.

METHODS

Female DF patients who were 18-50 years old at time of diagnosis (2000-2020) and had a history (≤5 years) of pregnancy at time of diagnosis were included.

RESULTS

Overall, 62 patients were included. The most common locations were abdominal wall (74%), pelvis (10%) and extremities (10%). Mutational analysis was conducted in 31 patients of which 94% had CTNNB1-mutations. Ten patients (16%) were diagnosed during pregnancy, while the remainder were diagnosed after pregnancy with a median time from delivery to diagnosis of 19 months (1-60). The frontline management was AS in 38 patients (61%) of whom 12 (33%) developed progressive disease and surgery in 23 patients (37%). In total, 30 patients underwent surgery and five had local recurrence (17%). Positive resection margins were no prognostic factor. Nine patients received systemic treatment in second- or third-line.

CONCLUSIONS

Pregnancy-associated DF generally has an indolent behavior, where our results underscore the difficulty of establishing a clear definition of this entity. This study shows that AS should be the frontline management strategy for pregnancy-associated DF. When active treatment is indicated, surgery is a good option with low recurrence rates, even with positive (R1) resection margins.

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.

Percutaneous cryoablation for desmoid fibromatosis: initial experience at a UK centre

AIM

To report the first UK experience of cryoablation in desmoid fibromatosis (DF) with particular focus on technique, safety, and efficacy.

MATERIALS AND METHODS

Patients were selected at multidisciplinary tumour board meetings at a specialist cancer hospital. Radiation dose, procedure duration, and number of cryoprobes were compared for small versus large tumours (>10 cm long axis). Response at magnetic resonance imaging (MRI) was evaluated using different criteria, and percentage agreement with clinical response as assessed in oncology clinic calculated.

RESULTS

Thirteen procedures were performed in 10 patients (eight women, median age 51 years, IQR 42-69 years) between February 2019 and August 2021. Procedures for large tumours had higher radiation dose (2,012 ± 1,012 versus 1,076 ± 519 mGy·cm, p=0.048) used more cryoprobes (13 ± 7 versus 4 ± 2, p=0.009), and were more likely to have residual unablated tumour (38 ± 37% versus 7.5 ± 10%, p=0.045). Adverse events were minor apart from one transient radial nerve palsy. Eight of 10 patients had symptomatic benefit at clinical follow-up (median 353 days, IQR 86-796 days), and three started systemic therapy mean 393 days later. All patients who had complete ablation demonstrated symptomatic response, with no instances of repeat treatment, recurrence, or need for systemic therapy during the study period. All progression occurred outside ablation zones.

CONCLUSION

Cryoablation for symptomatic DF is a reproducible technique with low, transient toxicity, where one or two treatments can achieve a meaningful response. Where possible, the ablation ice ball should fully cover DF tumours.

Evolving strategies for management of desmoid tumor

Desmoid tumors (DTs) are rare soft tissue mesenchymal neoplasms that may be associated with impairments, disfigurement, morbidity, and (rarely) mortality. DT disease course can be unpredictable. Most DTs are sporadic, harboring somatic mutations in the gene that encodes for β-catenin, whereas DTs occurring in patients with familial adenomatous polyposis have germline mutations in the APC gene, which encodes for a protein regulator of β-catenin. Pathology review by an expert soft tissue pathologist is critical in making a diagnosis. Magnetic resonance imaging is preferred for most anatomic locations. Surgery, once the standard of care for initial treatment of DT, is associated with a significant risk of recurrence as well as avoidable morbidity because spontaneous regressions are known to occur without treatment. Consequently, active surveillance in conjunction with pain management is now recommended for most patients. Systemic medical treatment of DT has evolved beyond the use of hormone therapy, which is no longer routinely recommended. Current options for medical management include tyrosine kinase inhibitors as well as more conventional cytotoxic chemotherapy (e.g., anthracycline-based or methotrexate-based regimens). A newer class of agents, γ-secretase inhibitors, appears promising, including in patients who fail other therapies, but confirmation in Phase 3 trials is needed. In summary, DTs present challenges to physicians in diagnosis and prognosis, as well as in determining treatment initiation, type, duration, and sequence. Accordingly, evaluation by a multidisciplinary team with expertise in DT and patient-tailored management are essential. As management strategies continue to evolve, further studies will help clarify these issues and optimize outcomes for patients.

Desmoid fibromatosis: is the current picture changing?

Desmoid fibromatosis is a locally aggressive tumor with an unpredictable clinical course. Surgery was once the mainstay of treatment, but the treatment protocol has been constantly evolving and currently active surveillance is the front-line approach. There have been significant insights into the molecular biology with the addition of mutational analysis of CTNNB1 adding to prognostic information. We present a review of the literature with current practice guidelines, also including novel therapeutic targets and ongoing clinical trials, to unravel the next step in the management of sporadic desmoid fibromatosis.

Desmoid-type fibromatosis: toward a holistic management

PURPOSE OF REVIEW

Desmoid-type fibromatosis, a rare locally aggressive fibroblastic proliferation, is a treatment challenge. This review aimed to explore recent data about the management of desmoid-type fibromatosis.

RECENT FINDINGS

New data underline the role of kinases and ɣ-secretase in stimulating cell proliferation and invasiveness in desmoid-type fibromatosis. This explains the proven activity of multikinase inhibitors (sorafenib or pazopanib) in the management of desmoid-type fibromatosis or the emerging role of a ɣ-secretase inhibitor. An international guideline for management was recently published, and this guideline take into account patient point of view. Lastly, recent studies highlight the multidimensional burden of desmoid-type fibromatosis, particularly health-related quality of life (HRQoL).

SUMMARY

Active surveillance with planned MRI is the first-line management in desmoid-type fibromatosis. A site-specific and stepwise approach should be considered for progressive desmoid-type fibromatosis. Further, a risk-benefit analysis that considers the side effects and long-term sequelae should be conducted before deciding to start any treatment. A less aggressive approach should be considered. Multikinase inhibitors are effective, but their tolerability and side effects should be discussed with the patients. The symptoms and HRQoL should be integrated in decision-making. Desmoid-type fibromatosis patients should be offered support to address their needs supportive care.