Infantile Sinonasal Myxoma Is Clinically and Genetically Distinct From Other Myxomas of the Craniofacial Bones and From Desmoid Fibromatosis

Sinonasal myxomas are rare benign tumors of the maxillary bone and sinus. There is published evidence that sinonasal myxomas occurring in children up to 3 years of age ("infantile sinonasal myxomas") are clinically distinctive and harbor Wnt signaling pathway alterations. Here, we characterized 16 infantile sinonasal myxomas and compared them to 19 maxillary myxomas and 11 mandibular myxomas in older patients. Clinical follow-up was available for 21 patients (46%) overall (median: 2.6 y; range: 4 mo to 21 y), including 10 of 16 infantile sinonasal myxomas (62%). None of the 8 resected infantile sinonasal myxomas recurred, despite positive margins in 6 of them. One incompletely resected infantile sinonasal myxoma underwent partial regression without additional treatment. In contrast, 4 of the 11 other myxomas with follow-up recurred (36%), including one that recurred twice. Imaging studies demonstrated all infantile sinonasal myxomas to be expansile lesions arising from the anterior maxillary bone adjacent to the nasal aperture, with peripheral reactive bone formation. Histologically, infantile sinonasal myxomas showed short, intersecting fascicles of bland fibroblastic cells with prominent stromal vessels. Examples with collagenous stroma showed some morphologic overlap with desmoid fibromatosis, although none showed infiltrative growth into adjacent soft tissue. Immunohistochemistry demonstrated nuclear β-catenin expression in 14 of 15 infantile sinonasal myxomas (93%), in contrast to 4 of 26 other myxomas of craniofacial bones (15%). Smooth muscle actin was expressed in only 1 of 11 infantile sinonasal myxomas (9%). Next-generation sequencing was successfully performed on 10 infantile sinonasal myxomas and 7 other myxomas. Infantile sinonasal myxomas harbored CTNNB1 point mutations in 4 cases (D32Y, G34E, G34R, and I35S), and none harbored alterations to the phosphorylation sites T41 and S45 that are altered in 99% of CTNNB1 -mutant desmoid fibromatoses. Three tumors showed alterations consistent with biallelic APC inactivation. Three infantile sinonasal myxomas that showed strong nuclear β-catenin expression were negative for CTNNB1 and APC alterations. Sequencing was negative for CTNNB1 or APC alterations in all 7 myxomas of craniofacial bones in older patients. Four of these myxomas in older patients (57%) showed copy number alterations, and all lacked known driving alterations. These findings support the notion that infantile sinonasal myxomas are clinically and genetically distinctive, and we propose the use of the diagnostic term "infantile sinonasal myxoma" to distinguish this tumor type from other myxomas of the craniofacial bones. Infantile sinonasal myxoma should be distinguished from desmoid fibromatosis because of its unique clinical presentation, more indolent clinical behavior, different morphology, different immunohistochemical profile, and different genetics. Given its indolent behavior even when marginally excised, infantile sinonasal myxoma can be managed with conservative surgery.

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.

High-Intensity Focused Ultrasound Ablation for Postoperative Recurrent Desmoid Tumors: Preliminary Results

This study was aimed at evaluating the feasibility, safety and therapeutic effects of high-intensity focused ultrasound ablation (HIFUA) in the treatment of post-operative recurrent desmoid tumors. From September 2017 to May 2020, 42 consecutive patients with pathologically proven desmoid tumors treated with HIFUA for the first time were enrolled. These were divided into two groups: post-operative recurrent group (30 cases) and non-surgery group (12 cases). The basic characteristics, treatment parameters, ablation efficacy, tolerance and adverse events were recorded and compared between groups. The minimum distance between the tumor and skin surface in the post-operative recurrent group was significantly smaller than that in the non-surgery group (6.9 mm vs. 10.8 mm, p = 0.011), but there was no significant difference in the other basic characteristics (p > 0.05). The average acoustic power and intensity of treatment in the post-operative recurrent group were significantly lower than those in the non-surgery group (p = 0.006 and 0.036, respectively), but there was no significant difference in the remaining parameters or in ablation efficacy between groups (p > 0.05). HIFUA was successfully performed, and a large volume of coagulation necrosis was obtained from all patients without serious or life-threatening adverse events. Furthermore, there was no significant difference in the incidence of moderate adverse events and average length of stay between groups (p > 0.05). The average power and intensity of HIFUA treatment were adversely affected by surgical scar and tumor infiltration along the surgical path. However, HIFUA can still be used as an effective minimally invasive therapy for the local control of post-operative recurrent desmoid tumors.

[Long-term effectiveness of "West China Classification" guided surgical treatment of desmoid-type fibromatosis in shoulder girdle]

Objective

To evaluate the long-term effectiveness of patients received surgical treatment under the guidance of "West China Classification" of desmoid-type fibromatosis (DTF) in the shoulder girdle.

Methods

The clinical data of 32 patients with DTF in the shoulder girdle admitted between June 2003 and December 2016 were retrospectively analyzed, including 14 males and 18 females, aged 14-56 years with an average age of 36.8 years. The maximum diameter of the tumor was 7-19 cm, with an average of 11.1 cm. According to the "West China Classification" of DTF in the shoulder girdle, there were 4 cases of region Ⅰ, 3 cases of region Ⅱ, 6 cases of region Ⅲ, 3 cases of region Ⅳ, 5 cases of regions Ⅰ+Ⅱ, 5 cases of regions Ⅱ+Ⅲ, and 6 cases of regions Ⅰ+Ⅱ+Ⅲ. In addition, the involvement of blood vessels and nerves was also taken into consideration for choosing a surgical approach. Finally, 12 cases were operated via anteroposterior approach (group A), 14 via posterior approach (group B), and 6 via combined anterior-posterior approach (group C). The 1993 Musculoskeletal Tumor Society (MSTS93) score (including pain, limb function, satisfaction, hand position, hand flexibility, and lifting ability), Japanese Orthopedic Association (JOA) score, range of motion (ROM) of shoulder joint (including flexion, extension, abduction, and adduction), and complications of patients in the 3 groups were recorded and compared.

Results

All the 32 patients were followed up 30-190 months, with an average of 94.6 months. At last follow-up, complications occurred in 5 cases (15.6%), including 2 cases (16.6%) in group A, 2 (14.3%) in group B, and 1 (16.6%) in group C. There was no significant difference in the incidence of complications among the 3 groups ( P=1.000). Tumor recurrence occurred in 5 (15.6%) cases, including 1 (8.3%) case in group A, 2 (14.3%) in group B, and 1 (16.6%) in group C. No significant difference was found in the recurrence rate among the 3 groups ( P=1.000). At last follow-up, MSTS93 score of pain, limb function, satisfaction, hand flexibility, and hand position in groups A and B were significantly better than those in group C ( P<0.05), even though no significant difference existed between group A and group B ( P>0.05). The lifting ability score in group C was significantly lower than in group A ( P<0.05), and no significant difference was found between other groups ( P>0.05). The JOA score and flexion, extension, abduction, and adduction activities of shoulder in groups A and B were significantly better than those in group C ( P<0.05). The extension activity in group A was significantly better than that in group B ( P<0.05), the flexion activity in group B was significantly better than that in group A ( P<0.05). There was no significant difference in other indexes between groups A and B ( P>0.05).

Conclusion

Taking a rational approach to fully expose and completely remove the tumor is the key point of surgical treatment for patients with DTF in the shoulder girdle. At the same time, preservation of vital structures and reconstruction of soft tissues should also be taken into consideration. Overall, surgical treatment under the guidance of "West China Classification" of DTF in the shoulder girdle has achieved satisfactory long-term effectiveness.

Desmoid-type fibromatosis of the head and neck in children: A changing situation

INTRODUCTION

Desmoid-type fibromatosis (DF) is a rare benign lesion known for its local aggressiveness. The tumor management still remains under debate. Primary head and neck (HN), represents the second most prevalently affected sitein children with DF. This study aims to analyze the specificity of HN-DF in children, focusing on long-term effects of the tumor and therapies.

METHODS

This retrospective multicenter study analyzed children treated for a HN-DF between 1993 and 2013. All medical files were reviewed and their outcomes analyzed according to the initial therapies provided.

RESULTS

Sixteen children were selected. Mandibular and submandibular areas were the main locations (11 cases). Eight children underwent chemotherapy as first-line therapy with tumor control in 3 cases and 5 cases needing additional treatment. Six children underwent primary surgery: isolated in 3 cases and with additional treatment after tumor progression in 3 cases. A wait-and-see attitude was adopted for 2 children without any additional treatment in 1 case, and followed by additional chemotherapy in the other case. Total burden of treatment to control the disease was a biopsy (1 case), surgery (3 unique cases, 1 multiple case), surgery with chemotherapy (6 cases), and exclusive medical therapies (5 cases). Surgical postoperative sequelae were facial palsy (cases of parotid gland affection), XI^th cranial nerve sacrifice or sensory impairment.

CONCLUSION

HN-DF is a local and extensive disease that is difficult to control with surgery alone. Sequelae are frequent due to the initial tumor location or therapies. Initial conservative strategies need to be discussed in a multidisciplinary way in order to try to control the disease with the minimal morbidity.

Clinical prognostic factors for pediatric extra-abdominal desmoid tumor: analyses of 66 patients at a single institution

Background and purpose

Pediatric desmoid tumor (PDT) is rare and has a high local recurrence rate. The purpose of the present study was to analyze clinical risk factors of local recurrence in PDT patients.

Materials and methods

We reviewed clinical data of 66 PDT patients from 2004 to 2015. All patients underwent macroscopically complete resection, and some recurrent tumors were prescribed radiotherapy. Factors such as sex, age at presentation, location, and proximity to nerves or vasculature were analyzed. The local recurrence rate and recurrence-free survival were analyzed with these factors.

Results

All patients in the present study were children and had extra-abdominal tumors. The median follow-up time was 6.6 years. Thirty-six (55%) patients had local recurrence. Age, sex, tumor site, tumor size, and proximity to nerves/vasculature had a significant impact on prognosis in univariate analysis. Radiotherapy decreased the local recurrence rate. In multivariate analysis, younger age, tumor location in buttocks, larger tumor, and proximity to important nerves/vasculature were independent risk factors for poor prognosis.

Conclusions

Favorable therapeutic strategies could be selected according to the preoperative prognostic risk factors. Radiotherapy should be considered for local recurrence of PDT.

Orbital Desmoid-Type Fibromatosis: A Case Report and Literature Review

Purpose

Desmoid-type fibromatosis is a benign fibrous neoplasia originating from connective tissue, fascial planes, and musculoaponeurotic structures of the muscles. Currently, there is no evidence-based treatment approach available for desmoid fibromatosis. In this article, a case of a patient in the pediatric age affected by desmoid fibromatosis localized in the orbit is presented. The aim of the article is to describe this unusual and rare location for the desmoid fibromatosis and outline the principle phases in the decision-making process and the therapeutic alternatives for a patient affected by desmoid fibromatosis.

Methods

The protocol of this review included study objectives, search strategy, and selection criteria. The primary end point of this study was to analyze the head and neck desmoid fibromatosis. The secondary end point was to identify the available therapies and assess their specific indications.

Results

The mean age of patients was 18.9 years ranging from 0 to 66, and 52% were female. A bimodal age distribution was observed, and two age peaks were identified: 0–14 years (57%) and 28–42 years (18%). The most common involved areas were the mandible (25%) followed by the neck (21%). In 86% of the cases, the treatment was the surgical resection of the disease, and only in 5% of the cases, the surgical resection was followed by adjuvant radiotherapy.

Conclusion

The orbital location is extremely rare, especially in the pediatric population. The management of desmoid fibromatosis is based on the function preservation and the maintenance of a good quality of life, but in case of symptomatic patients or aggressive course of the disease or risk of functional damages, the surgical approach may be considered. Therapeutic alternatives to surgical resection are radiotherapy and systemic therapy.

Efficacy of vinorelbine combined with low-dose methotrexate for treatment of inoperable desmoid tumor and prognostic factor analysis

Objective

To assess the efficacy of conservative chemotherapy for inoperable desmoid tumor (DT) and analyze the prognostic factors.

Methods

From November 2008 to April 2016, 71 patients of inoperable DT were treated with vinorelbine and low-dose methotrexate in the Department of Bone and Soft Tissue Tumors, Peking University Cancer Hospital & Institute, and enrolled in this retrospective study. The chemotherapy duration is one year. The efficacy of chemotherapy and the prognosis were observed.

Results

Of the 71 patients, 55% were female. Age of onset varied from 1 to 47 years, and the median age was 14 years. Only 11 (15.5%) cases suffered primary tumor. The distribution of the site of tumors was: 31 (43.7%) in the trunk, 36 (50.7%) in the limbs, and 4 (5.6%) in the peritoneal and pelvic cavity. The size of tumor (the maximum diameter) differed from 2 to 37 cm with a mean of 9.3 cm. The median follow-up duration was 28 (range, 6-87) months. Common side effects included: nausea and vomiting, liver injury, bone marrow suppression and oral ulcers. When the chemotherapy finished, 1 (1.4%) case achieved complete response, 24 (33.8%) achieved partial response, 37 (52.1%) achieved stable disease and 9 (12.7%) had progressive disease. The overall response rate was 87.3%. The progression-free survival (PFS) of the participants were from 6 to 87 months, and the 2-, 3- and 5-year PFS was 79.9%, 68.4% and 36.3%, respectively. No significant difference was identified in PFS in subgroups of gender, age of onset, age of chemotherapy, tumor site and tumor size.

Conclusions

For recurrent, inoperable and progressive DT, enough course of chemotherapy with vinorelbine combined with low-dose methotrexate was an optional choice for local control.

Pediatric desmoid fibromatosis of the parapharyngeal space: A case report and review of literature

Desmoid fibromatosis, or aggressive fibromatosis, is a benign but locally infiltrative fibroblastic neoplasm arising from fascial or musculoaponeurotic tissues. Although lacking metastatic potential, head and neck fibromatosis can have significant functional or cosmetic morbidities. 7%-15% of all desmoid tumors are seen in the head and neck region, 57% of which occur in the pediatric population. The incidence of pediatric desmoid tumor peaks around age 8. Treatment of choice is complete surgical resection; however, local recurrence is common. We present a case of a 14-month-old male with an 8-cm desmoid tumor in the right parapharyngeal space and provide an overview of diagnosis and management of pediatric head and neck fibromatosis. This is the largest desmoid tumor of the parapharyngeal space in the youngest patient described in the literature.

Is wide resection obsolete for desmoid tumors in children and adolescents? Evaluation of histological margins, immunohistochemical markers, and review of literature

Desmoid fibromatosis is a benign fibroblastic neoplasm with high recurrence rates predominantly observed in pediatric and adolescent patients. The use of wide resection margins has been discussed controversially in literature. In addition, data on non-surgical treatment is limited as phase III studies are still missing. Nineteen patients under the age of 18 years were identified. Tumor location, surgical treatment for primary or recurrent tumors, resection margins, medical neo-/adjuvant treatment, time to recurrence as well as immunohistochemical markers (estrogen receptor, ER α and β, progesterone and androgen receptors, somatostatin, Ki-67, c-kit, platelet-derived growth factor receptors, PDGFRs, α and β, β-catenin) were evaluated. The mean age at diagnosis was 6.6 years, with a mean follow-up of 114 months. Recurrences were detected in four out of nineteen patients. Surprisingly, the recurrence rate was not influenced by type of resection used (R0, R1/2). All samples were tested negative for ER α, somatostatin, and progesterone receptor. In contrast, a majority of tumors showed positive results for PDGFR α and β and β-catenin. No correlation between positive immunohistochemical markers and tumor recurrences was detectable. In conclusion, recurrence rates are not depending on resection type and immunohistochemical markers seem to behave differently in children and adolescents in contrast to adult patients.