Myofibrosarcoma: a clinicopathologic study

Myofibroblastic sarcoma in breast: a case report and literature review

Myofibroblastic sarcoma is a malignancy in which myofibroblasts are the main component, with a very low incidence. In this study, we report a case of low-grade myofibroblastic sarcoma (LGMS) in the breast. After the diagnosis of LGMS, the patient received a mastectomy. The patient showed no relapse or progression during the follow-up time of 3 months following the operation. LGMS in the breast is extremely rare, and the limited experience with its diagnosis and treatment brings obstacles to doctors. Therefore, this report summarizes the preoperative diagnosis, treatment, and prognosis of breast LGMS through a literature review.

Low-grade myofibrosarcoma of the maxillary sinus: Two case reports

BACKGROUND

Low-grade myofibroblastic sarcoma (LGMS) is an extremely rare tumor characterized by the malignant proliferation of myofibroblasts. LGMS most commonly develops in adults, predominantly in males, in the head and neck region, oral cavity, especially on the tongue, mandible, and larynx. This article presents 2 cases of LGMS localized to the maxillary sinus and provides an overview of the available literature.

CASE SUMMARY

Two patients with LGMS located in the maxillary sinus underwent surgery at the Department of Head and Neck Surgery. Case 1: A 46-year-old patient was admitted to the clinic with suspected LGMS recurrence in the right maxillary sinus (rT4aN0M0), with symptoms of pain in the suborbital area, watering of the right eye, thick discharge from the right nostril, and augmented facial asymmetry. After open biopsy-confirmed LGMS, the patient underwent expanded maxillectomy of the right side with immediate palate reconstruction using a microvascular skin flap harvested surgically from the middle arm. The patient qualified for adjuvant radiotherapy for the postoperative bed, with an additional margin. Currently, the patient is under 1.5 years of observation with no evidence of disease. Case 2: A 45-year-old man was admitted to our clinic with facial asymmetry, strabismus, exophthalmos, and visual impairment in the right eye. Six months earlier, the patient had undergone partial jaw resection at another hospital for fibromatosis. A contrast-enhanced computed tomography scan revealed a tumor mass in the postoperative log after an earlier procedure. An open biopsy confirmed low-grade fibrosarcoma (rT4aN0M0). The patient qualified for an extended total right maxillectomy with orbital excision and right hemimandibulectomy with immediate microvascular reconstruction using an anterolateral thigh flap. The patient subsequently underwent adjuvant radiotherapy to the postoperative area. After 9 months, recurrence occurred in the right mandibular arch below the irradiated area. The lesion infiltrated the base of the skull, which warranted the withdrawal of radiotherapy and salvage surgery. The patient qualified for palliative chemotherapy with a regimen of doxorubicin + dacarbazine + cyclophosphamide and palliative radiotherapy for bone metastases. The patient died 26 months after surgical treatment. The cases have been assessed and compared with cases in the literature.

CONCLUSION

No specific diagnostic criteria or treatment strategies have been developed for LGMS. The treatment used for LGMS is the same as that used for sinonasal cancer radical tumor excision; adjuvant radiotherapy or chemoradiotherapy should also be considered. They have low malignant potential but are highly invasive, tend to recur, and metastasize to distant sites. Patients should undergo regular follow-up examinations to detect recurrence or metastasis at an early stage. Patients should be treated and observed at the highest referral centers.

Recurrent USP6 rearrangement in a subset of atypical myofibroblastic tumours of the soft tissues: low-grade myofibroblastic sarcoma or atypical/malignant nodular fasciitis?

AIMS

Low-grade myofibroblastic sarcoma (LGMS) is a rarely metastasizing myofibroblastic tumour mostly affecting extremities and the head and neck of adults. Histologically, it shows long infiltrative fascicles of spindle cells with moderate nuclear atypia. By immunohistochemistry, it stains positive for smooth muscle actin (SMA) and sometimes for desmin. To date, no recurrent genetic abnormalities have been described. Ubiquitin-specific peptidase 6 (USP6) gene rearrangement is typically found in some benign bone and soft-tissue tumours including nodular fasciitis (NF), among others. Nevertheless, rare cases of USP6-rearranged tumours resembling NF with atypical features have been reported.

METHODS AND RESULTS

One index case of LGMS of the deltoid in a 56-year-old man presented the THBS2::USP6 translocation by RNA sequencing (Archer FusionPlex Sarcoma v2 panel). Further screening of 11 cases of LGMS using fluorescent in situ hybridization (FISH) analysis with a USP6 break-apart probe identified two additional cases. These cases were investigated with RNA-sequencing, and a RRBP1::USP6 translocation was detected in one. The other case was not assessable because of low-quality RNA. Noteworthy, rearranged LGMSs presented distinctive features including variable multinodular/plexiform architecture, prominent vasculature with occasional wall thickening, scattered osteoclast-like multinucleated giant cells, and peripheral lymphoid aggregates.

CONCLUSION

Our findings support the notion that among soft-tissue neoplasms with fibroblastic/myofibroblastic phenotype, USP6 rearrangement is not limited to benign tumours, and warrants further investigation of genetic changes in myofibroblastic sarcomas.

Anlotinib in combination with pembrolizumab for low-grade myofibroblastic sarcoma of the pancreas: A case report

BACKGROUND

Low-grade myofibroblastic sarcoma (LGMS) is a rare spindle cell sarcoma especially in the pancreas, with myofibroblastic differentiation. Hitherto, only a few cases have been reported.

CASE SUMMARY

Herein, we report a case involving the discovery of a pancreatic mass detected during a routine physical examination. Subsequent imaging and pathological tests of the patient led to the diagnosis of LGMS of the pancreas. Following surgical intervention, the patient experienced recurrence and metastasis. Conventional treatment is not effective for postoperative recurrent pancreatic LGMS with multiple metastases. After communicating with the patients and their families, informed consent was obtained for the treatment of anlotinib combined with pembrolizumab. Evaluation of imaging and clinical symptoms post-treatment revealed a relatively favorable response to the combination of anlotinib and pembrolizumab.

CONCLUSION

Based on the comprehensive literature review, our report aimed to provide evidence for a better understanding of the disease characteristics, diagnostic criteria, imaging findings, and identification of LGMS. And explore novel treatment strategies for this disease.

A Systematic Review and Illustrative Case Presentation of Low-Grade Myofibroblastic Sarcoma (LGMS) of the Extremities

INTRODUCTION

Low-grade myofibroblastic sarcoma (LGMS) is a rare tumor entity which occurs in the subcutaneous and deep soft tissues; it is less common in the bone with a predilection for the extremities and the head and neck region. As confirming the diagnosis is difficult and treatment strategies are not standardized, we aimed to identify patient and tumor characteristics, and to summarize treatment strategies and their clinical outcomes to guide surgeons.

METHODS

Included were full articles reporting patients with histology of LGMS in the extremities, excluding tumors of the trunk. All patients underwent surgery but with different extend, from marginal to wide resection. Included studies should inform about local recurrence, metastasis, or evidence of disease, depending on the surgical treatment. We conducted a structured search using MEDLINE (via PubMed), Web of Science, EMBASE and Cochrane Central Register of Controlled Trials (CENTRAL) to identify studies on low-grade myofibroblastic sarcoma of the extremities. Study designs like randomized controlled trials, systematic reviews, prospective trials, retrospective studies, and case reports were included. Prospective studies and comparative studies were not available at all. Therefore, meta-analysis was not possible and statistical analysis was purely descriptive.

RESULTS

Of the 789 studies identified from our initial search, 17 studies including 59 cases reported LGMS of the extremities with the surgical treatment and clinical outcome and were therefore analyzed. In addition, we present the rare case and surgical management of a 28-year-old male patient with residual LGMS of the thumb after an initial incomplete resection. The current literature suggests that a wide excision with R0 margins should be considered the standard treatment for LGMS. In cases where surgery leads to significant functional impairment, individual options like free tissue transfer from a donor site have to be considered. Therefore, we also present an illustrative case. For all selected case series and case reports, a high risk of confounding, selection bias, information bias, and reporting bias must be anticipated. Nevertheless, this systematic review provides a comprehensive overview on surgical treatment and clinical outcomes in LGMS surgery of the extremities.

Low-Grade Myofibroblastic Sarcoma on Back with Repeated Localized Recurrence and Regional Metastasis

Low-grade myofibroblastic sarcoma (LGMS) is a rare spindle cell tumor with indolent course. Due to rarity and low-grade histologic features of LGMS, accurate diagnosis is challenging. We report a 63-year-old female patient with a three-month history of a 3.1 cm×2.5 cm sized, firm, skin-colored, painless, protruding left back mass. Initial excisional biopsy was performed and the mass was diagnosed as nodular fasciitis. After 18 months after excision, the mass recurred with pain and grew larger. Considering the clinical manifestations, diagnostic impression was changed as dermatofibrosarcoma protuberans not nodular fasciitis. Second wide excision was performed and the histopathology revealed proliferative atypical spindle cells with moderate nuclear atypia and a distinctive whorling pattern, which is suggestive of low-grade sarcoma. Additional computed tomography and positron emission tomography revealed no metastasis and suspicious residual viable malignant tissue. To remove suspicious residual tumor, third wide excision were performed and the diagnosis confirmed as LGMS. A microscopically clear resection was achieved with deep and lateral safety margin 0.6 cm each. Despite of postoperative radiotherapy with 35 times, recurrence of the tumor and lung metastasis was found after 7 months later. LGMS rarely metastasizes and occurs most commonly in the head and neck region. Thus, we report a rare case of LGMS on back which repeated localized recurrence and regional lung metastasis occurred despite wide excision and adjuvant radiotherapy.

Low-Grade Myofibroblastic Sarcoma of the Oral and Maxillofacial Region: An International Clinicopathologic Study of 13 Cases and Literature Review

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical tumor composed of myofibroblasts with a variety of histological patterns and with a high tendency to local recurrence and a low probability of distant metastases. LGMS has predilection for the head and neck regions, especially the oral cavity. This study aimed to report 13 new cases of LGMS arising in the oral and maxillofacial region. This study included LGMS cases from five oral and maxillofacial pathology laboratories in four different countries (Brazil, Peru, Guatemala, and South Africa). Their clinical, radiographic, histopathological, and immunohistochemical findings were evaluated. In this current international case series, most patients were females with a mean age of 38.7 years, and commonly presenting a nodular lesion in maxilla. Microscopically, all cases showed a neoplasm formed by oval to spindle cells in a fibrous stroma with myxoid and dense areas, some atypical mitoses, and prominent nucleoli. The immunohistochemical panel showed positivity for smooth muscle actin (12 of 13 cases), HHF35 (2 of 4 cases), β-catenin (3 of 5 cases), desmin (3 of 11 cases), and Ki-67 (range from 5 to 50%). H-caldesmon was negative for all cases. The diagnosis of LGMS was confirmed in all cases. LGMS shows predominance in young adults, with a slight predilection for the female sex, and maxillary region. LGMS should be a differential diagnosis of myofibroblastic lesions that show a proliferation of spindle cells in a fibrous stroma with myxoid and dense areas and some atypical mitoses, supporting the diagnosis with a complementary immunohistochemical study. Complete surgical excision with clear margins is the treatment of choice. However, long-term follow-up information is required before definitive conclusions can be drawn regarding the incidence of recurrence and the possibility of metastasis.

Low-grade malignant myofibroblastic sarcoma of the larynx: a case report

Low-grade myofibroblastic sarcoma (LGMS) is a rare malignant mesenchymal tumor derived from myofibroblasts. It is commonly identified in the head and neck, and particularly in the oral cavity, but rarely in the larynx. In this case report, we describe a patient who presented with hoarseness and underwent electronic fiber laryngoscopy, which revealed a neoplasm on the surface of his left vocal cord. The vocal cord tumor was resected under general anesthesia, and a malignant LGMS was diagnosed on postoperative pathologic examination. The results of immunohistochemical staining of the sections for vimentin (diffuse +), actin (partial +), and desmin (-) were consistent with this diagnosis. The patient recovered well after the surgery, and there was no recurrence of the neoplasm.

Risk Factors for Recurrence and the Role of Radiotherapy in Low-grade Myofibroblastic Sarcoma: A Systematic Review

Low-grade myofibroblastic sarcoma (LGMS) is a rare malignancy that commonly occurs in the head and neck region. The role of radiotherapy has been unclear in treating LGMS and the risk factors for recurrence have remained undefined. The objective of this study is to determine risk factors for the recurrence of LGMS in the head and neck as well as the role of radiotherapy in the treatment of LGMS. A comprehensive review of the literature was performed through Pubmed leading to the inclusion of 36 articles after our inclusion and exclusion criteria were applied. Continuous variables were analyzed with a 2-tail unpaired t test. Categorical variables were assessed with the χ 2 test or Fisher exact test. Logistic regression and multivariable logistic regression analysis with 95% CIs were used to obtain odds ratios. LGMS most commonly occurred in the oral cavity (49.2%). Half of all recurrences occurred in the paranasal sinuses/skull base. LGMS occurring at the paranasal sinuses/skull base had a significantly increased risk of recurrence compared with other subsites within the head and neck (odds ratio: -40; 95% CI: 2.190, 762.005; P = 0.013). The average time to recurrence of LGMS was 19.2 months. Adjuvant treatment with radiation did not improve recurrence rates. Sex, tumor size, or bony involvement were not found as risk factors for recurrence. Patients with LGMS of the paranasal sinuses and skull base are at high risk for recurrence and should be monitored closely. The role of adjuvant radiation treatment in these patients remains unclear.

Clinical Outcome of Low-Grade Myofibroblastic Sarcoma in Japan: A Multicenter Study from the Japanese Musculoskeletal Oncology Group

This retrospective multicenter study aimed to analyze the clinical features and prognosis of 24 patients diagnosed with LGMS between 2002 and 2019 in the Japanese sarcoma network. Twenty-two cases were surgically treated and two cases were treated with radical radiotherapy (RT). The pathological margin was R0 in 14 cases, R1 in 7 cases, and R2 in 1 case. The best overall response in the two patients who underwent radical RT was one complete response and one partial response. Local relapse occurred in 20.8% of patients. Local relapse-free survival (LRFS) was 91.3% at 2 years and 75.4% at 5 years. In univariate analysis, tumors of 5 cm or more were significantly more likely to cause local relapse (p < 0.01). In terms of the treatment of relapsed tumors, surgery was performed in two cases and radical RT was performed in three cases. None of the patients experienced a second local relapse. Disease-specific survival was 100% at 5 years. A wide excision aimed at the microscopically R0 margin is considered the standard treatment for LGMS. However, RT may be a viable option in unresectable cases or in cases where surgery is expected to cause significant functional impairment.

A 37-Year-Old Man with Myofibroblast Sarcoma Combined with Pleural Maculopathy: Case Report

Myofibroblastic sarcoma (MS) is a malignant tumor of soft tissue or bone that can occur in children or adults, with a high rate of recurrence and metastasis. We report a case of low-grade malignant MS of the left shoulder, diagnosed based on pathological examination and immunohistochemical staining. However, the patient had unexplained pleural maculopathy. The patient passed away 6 months after the diagnosis of myofibroblast sarcoma due to multiple metastases throughout the sarcoma. Combined with the patient's history, ancillary findings, and after MDT discussion, the patient was ultimately considered to have a high probability of myofibroblast sarcoma combined with pleural maculopathy. In conclusion, when a patient is diagnosed with myofibroblast sarcoma in combination with pleural macula, in the absence of other causative factors, a deep tissue biopsy of the pleura should be actively performed to confirm the diagnosis.

Low-Grade Malignant Myofibroblastic Sarcoma of the Larynx: A Case Report and Literature Review

Squamous cell carcinomas predominate in laryngeal malignancies, while spindle cell tumors, typically derived from non-epithelial tissues, are uncommon, accounting for 0.3%-1% of all malignant laryngeal tumors. Low-grade malignant myofibroblastic sarcoma (LGMS) is an extremely rare, atypical myofibroblastic tumor classified as a spindle cell tumor that primarily affects the head and neck region. There have been few reports in the literature regarding the LGMS of the larynx. LGMS of the larynx was discovered during a pathological biopsy. There was no recurrence during the 6-month follow-up after the total laryngectomy.

Low-grade myofibroblastic sarcoma of the proximal femur: A case report and literature review

RATIONAL

Low-grade myofibroblastic sarcoma (LGMS) is an atypical type of tumor composed of myofibroblasts. LGMS in the femoral head neck junction is extremely rare and no case treated by hip arthroscopy was reported.

PATIENT CONCERNS

We reported a case of LGMS in the femoral head neck junction treated by hip arthroscopy. A 30-year-old female was admitted to our hospital with discomfort and pain after left hip sprained one year prior. Physical examination revealed swelling of the left hip and magnetic resonance images showed a soft tissue mass in the femoral head neck junction.

DIAGNOSIS

Via microscopy of pathological specimens, spindle cell proliferative lesions, atypia of some cells, and mitotic figures/pathological mitotic figures of some cells were observed. Immunohistochemistry revealed positive for smooth muscle actin, focally positive for CD34 and CD68, while negative for S-100, desmin, and anaplastic lymphoma kinase. The imaging, histomorphological and immunohistochemical features suggested a final diagnosis of LGMS of the proximal femur.

INTERVENTIONS

This patient underwent hip arthroscopy for excision of the soft tissue mass.

OUTCOMES

The clinical and imaging follow-up at 6 months postoperatively showed that surgery had achieved good clinical outcomes.

LESSONS

To the best of our knowledge, this is the first case report of LGMS in the femoral head neck junction treated by hip arthroscopy. Beyond the present case, other 120 cases from 58 literatures (1998-2022) are reviewed and discussed. The age of LGMS patients ranged from 11 months to 77 years and the male-to-female ratio was approximately 1.28:1. The location distribution of previously reported LGMS cases and the present case was as follows: Head&neck (45.90%), trunk (30.33%), and extremity (23.77%). Hip arthroscopic excision of LGMS may achieve relatively good clinical outcomes.

A rare low-grade myofibroblastic sarcoma in lower jaw with the resemblance to benign lesions

Background

Low-grade myofibroblastic sarcoma (LGMS) is a rare solid infiltrative soft tissue tumor with a predilection for the head and neck region.

Case presentation

We report the diagnostic steps of a fast-growing lesion of the lower left jaw in a 45-year-old otherwise healthy woman. A first biopsy and subsequent histopathological examination showed potential differentials of a benign myofibroma, benign nodular fasciitis or an LGMS. This diagnostic overlap was a challenge for the decision of the further treatment approach. The treatment consisted of a segmental en bloc resection of the mandible including the second premolar, first and second molar. Histopathological examination of the resected tumor confirmed an LGMS.

Conclusion

The histopathologic resemblance of LGMS to a range of benign and reactive tumors may lead to misdiagnosis and mistreatment. The rarity of LGMS explains the lack of established treatment protocols. This case shows the importance of adequate clinical decisions, expertise in the histopathology of rare tumors and interdisciplinary exchange to achieve state-of-the-art patient management.

Surgical treatment and long-term outcomes of low-grade myofibroblastic sarcoma: a single-center case series of 15 patients

Background

Low-grade myofibroblastic sarcoma (LGMS) is a poorly studied, rare, soft tissue sarcoma. LGMS is characterized by a low malignancy potential, tendency for local recurrence, and low likelihood of distant metastases. However, no studies have reported on the surgical treatment method and its long-term outcomes.

Methods

We included all patients treated for LGMS at our institution between March 2010 and March 2021. Medical charts were retrospectively reviewed to collect demographic information, as well as information about the clinical course, tumor characteristics, and outcomes. Statistical analysis was performed to identify the factors associated with the recurrence rate.

Results

Fifteen patients who underwent surgical treatment were enrolled in this study. There were seven cases in the upper extremities, four in the trunk area, three in the lower extremities, and one in the head and neck area. There were no metastatic cases and two cases of local recurrence.

Conclusions

The incidence of LGMS in the extremities or trunk may be higher than expected based on the current literature. Univariate analysis showed that local tissue invasion and surgical method could be associated with local recurrence. Although further large studies are needed to establish risk factors of local recurrence or extent of resection margins, based on our study, wide local excision under the proper diagnosis is the most important treatment.

Giant chondroid lipoma of the breast: A case report and literature review

Chondroid lipoma is a rare benign lesion affecting the breast, in which the diagnosis of malignancy is difficult to be excluded during preoperative studies. In this respect, a correct histopathological diagnosis is mandatory in order to avoid overdiagnosis and subsequently overtreatment. In the present study, the case of a 61-year-old patient who self-referred for the development of a large tumor at the level of the left breast is reported. Biopsy raised the suspicion of a chondroid lipoma; thus, the patient was submitted to conservative surgery. The lesion was completely excised by performing a total mastectomy. The histopathological studies confirmed the presence of chondroid lipoma, with no signs of malignant transformation. At the 24-month follow-up interval no signs of recurrence were detected. In conclusion, although it may reach significant dimensions, giant chondroid lipoma of the breast is a benign lesion that may benefit from conservative treatment and does not recur.

Limbal, low-grade myofibroblastic sarcoma: Case report and literature review

Low-grade myofibroblastic sarcoma is a relatively recently-described neoplasm of the myofibroblasts having a predilection for the head and neck region. Ophthalmic involvement is extremely rare. Limbal involvement has not yet been documented in the literature. We describe one such case involving the limbus of a 48-year-old Asian male.

Cutaneous mesenchymal tumors treated with Mohs micrographic surgery: a comprehensive review

Cutaneous mesenchymal tumors (CMT) are rare tumors with wide clinicopathologic heterogeneity. Treatment of malignant cutaneous mesenchymal tumors traditionally includes wide local excision (WLE), though Mohs micrographic surgery (MMS) has been increasingly used. A PubMed literature review of articles from inception until September 2019 related to malignant CMT and surgical treatment with MMS or WLE was completed. Dermatofibrosarcoma protuberans treated with MMS recurred in 1.2% of patients with no reported metastasis. Atypical fibroxanthoma treated with MMS recurred and metastasized in 2.7 and 2.5%, respectively. Undifferentiated pleomorphic sarcoma treated with MMS recurred in 32% with an unknown metastatic rate. Superficial leiomyosarcoma treated with MMS recurred in 3.8% with no reported metastasis. Cutaneous angiosarcoma and myofibrosarcoma treated with MMS have shown no recurrence or metastatic disease, but literature is sparse. The rarity of malignant CMT and the lack of comparative data on treatment make conclusive treatment recommendations difficult. However, recent literature suggests MMS is a useful option and potentially a superior treatment for primary cutaneous mesenchymal tumors.

Low-Grade Myofibroblastic Sarcoma of the Oral Cavity: A Report of Three Cases Illustrating an Emerging Disease in Children

Low-grade myofibroblastic sarcoma (LGMS) is a mesenchymal tumor of myofibroblasts that occurs more frequently in adults. A series of three cases is presented to illustrate that LGMS may also occur within the oral cavity in children and adolescents. The first case (Case 1) occurred intra-osseously in the mandible, while the remaining two presented as gingival swellings and were purely restricted to soft tissue (Cases 2 and 3). The intra-osseous lesion arose in a 7-year-old girl, whereas the gingival lesions were observed in a 12-year-old girl (Case 2) and a 13-year-old boy (Case 3). Histopathologically, all cases were composed of spindle shaped cells arranged into long fascicles showing mild to moderate degree of nuclear atypia. Ki-67 (MIB-1) proliferation activity was relatively low, amounting to 3–5% in all cases. Immunohistochemically, all cases showed smooth muscle actin (SMA) positivity in spindle cells, while desmin, beta catenin, cytokeratin, and CD34 were negative, resulting in a diagnosis of LGMS. In conclusion, current series of three cases of LGMSs that occurred in the oral cavity in a child and two adolescent patients is presented to highlight an emerging disease that requires additional data for further characterization.

Low-grade myofibroblastic sarcoma of the levator scapulae muscle: a case report and literature review

BACKGROUND

Low-grade myofibroblastic sarcoma (LGMS) is described as a distinct atypical myofibroblastic tumor often with fibromatosis-like features and predilection for the head and neck, especially the oral cavity and larynx. LGMS arising in the levator scapulae muscle is extremely rare.

CASE PRESENTATION

A 69-year-old woman was admitted to our hospital because she noticed a hard mass in her left neck six months prior. Magnetic resonance images (MRI) showed a soft tissue tumor of the left levator scapulae muscle. A core needle biopsy showed cellular fascicles or a storiform growth pattern of spindle-shaped tumor cells with minimally atypia. Immunohistochemistry revealed focally positive for α-smooth muscle actin (α-SMA), negative for S-100, and a low-grade spindle cell sarcoma was suspected. Following a biopsy, the tumor was resected with a wide surgical margin. Immunohistochemical staining was a positive for vimentin and α-SMA and negative for desmin, CD34, nuclear β-catenin, and h-caldesmon. LGMS diagnosis was determined based on the histopathological findings. The patient was alive with no evidence of disease eight years after the surgery.

CONCLUSIONS

To the best of our knowledge, this is the first case report of LGMS arising in the levator scapulae muscle. In addition to the case report, 48 reports with 103 LGMS cases are reviewed and discussed. In previous reports of LGMS, there were 43 females and 60 males, with a mean age of 43.0 years (range, 2-75). There were 13 (12.6%) patients aged < 18 years, 67 (65.1%) patients aged 18 to 59 years, and 23 (22.3%) patients aged ≥60 years. The average tumor size was 4.4 cm (range: 0.4-22.0). The commonest sites of LGMS was the tongue. Tumor growth patterns were evaluated in 52 cases, and 44 cases (84.6%) showed infiltrative growth patterns. Local recurrence was 26.7%, and distant metastasis was 4.4%. Because of the locally aggressive feature, it is important to diagnose LGMS with biopsy and to excise the tumor with an adequately wide margin.

Primary low-grade myofibroblastic sarcoma: A rare case report of this tumor in the orbit and literature review

Low-grade myofibroblastic sarcoma (LGMS) is an exceedingly rare, malignant tumor with myofibroblastic differentiation. It frequently occurs in the oral cavity and extremities, despite being classified as a distinct entity by the World Health Organization (WHO). Here, we report a rare case of orbital LGMS occurring in an 11-month-old baby with a 3.2 × 2.4 × 2.1 cm mass. LGMS was diagnosed based on the histological and immunohistochemical findings. Previous literature suggests that surgical resection with clear margins is an appropriate method for the treatment of LGMS, and combined adjuvant therapy (local radiotherapy with or without chemotherapy) can improve the prognosis, but further studies are needed.

Evaluation and Management of an Uncommon Tumor of the Larynx: A Case Report and Literature Review of Laryngeal Low-Grade Myofibroblastic Sarcoma

Low-grade myofibroblastic sarcoma (LGMS) of the larynx is an uncommon entity. These mesenchymal tumors of the larynx are rare and account for approximately 0.3% to 1.0% of all neoplasms at this site. We report a rare case of LGMS of the larynx that involved the larynx of a 63-year-old man with a history of hoarseness of voice. The patient was treated with total laryngectomy with partial pharyngectomy without any adjuvant treatment. Histopathologically, the tumor was composed of spindle cells that manifested variable cellular anaplasia and expressed smooth muscle actin (SMA). Our patient is disease-free two years after surgery. The authors emphasize the clinical and histopathological findings and treatment of this case with a literature review. This case is among the few reported cases of LGMS of the larynx. It enlightens the classical clinical findings, histopathology, differential diagnosis, and treatment. Surgical excision with negative margins requires no adjuvant therapy.

High-grade myofibroblastic sarcoma of the pleura: A case report and literature review

High‐grade myofibroblastic sarcoma (HGMS) is a rare cancer that has high recurrence and metastatic rates. Here, we report the first case of HGMS originating from the pleura. Based on the findings of pleural biopsy, pathological examination and immunohistochemical staining, grade III myofibroblastic sarcoma (MS) was diagnosed. The patient underwent eight cycles of chemotherapy (epirubicin and ifosfamide), followed by radiotherapy. As of May 2020, the patient had been followed for six months and no tumor progression had occurred.

Key points

This is the first report of high‐grade myofibroblastic sarcoma originating from the pleura. The patient was treated via nonsurgical strategies, including chemotherapy and radiotherapy.

Is there a role for chemotherapy and radiation in the treatment of patients with low-grade myofibroblastic sarcoma?

PURPOSE

Low-grade myofibroblastic sarcoma (LGMS) is a rare entity with a predilection for the head and neck. There are still no optimal treatment strategies for patients with LGMS. We retrospectively investigated the efficacies of chemotherapy and radiation treatment for patients with LGMS.

METHODS/PATIENTS

We obtained data from the Surveillance, Epidemiology, and End Result (SEER) database for 96 patients diagnosed with LGMS between 2001 and 2015. We used Kaplan-Meier curves and log-rank tests to estimate overall survival (OS) and Cox proportional hazard regression to identify prognostic factors.

RESULTS

The median age of the patients was 55.0 years. Twenty-two of the patients had LGMS in the head and neck region. Of the 96 patients, 86 (89.6%) received surgical treatment, 28 (29.2%) received radiation treatment, and 20 (10.4%) received chemotherapy. The mean OS was 125.2 [95% confidence interval (CI) 106.3-144.2] months. The 1, 3, 5, and 10-year OS rates were 88%, 77%, 70%, and 59%, respectively. Age greater than 60 years, positive nodal status, and no surgical treatment were independent prognostic factors for patients with LGMS, whereas chemotherapy and radiation treatment were not.

CONCLUSIONS

Surgical resection is the most effective therapy for LGMS. Chemotherapy and radiation had limited effects on survival improvement for patients with LGMS. Therefore, chemotherapy and/or radiation therapy should not be routinely performed in LGMS, especially for those with negative margins after surgery.

Low-Grade Myofibroblastic Sarcoma Arising From Keloid Scar on the Chest Wall After Thoracic Surgery

Keloids are considered as benign fibroproliferative skin tumors, and rare cases of malignancies have been reported. We present a case of low-grade myofibroblastic sarcoma arising from a recurrent painful keloid scar on the right chest wall after video-assisted thoracic surgery for pneumothorax in a 77-year-old man. Wide composite excision of the keloid, surrounding ribs, and partial diaphragm were performed. The chest wall pleural defect was reconstructed with Teflon (Chemours, Wilmington, DE), and soft tissue was reconstructed with a transverse rectus abdominis myocutaneous flap. This case highlights that refractory keloids may be considered a harbinger of malignancy.

Soft Tissue Special Issue: Fibroblastic and Myofibroblastic Neoplasms of the Head and Neck

Fibroblastic and myofibroblastic neoplasms of the head and neck encompass a group of rare tumor types with often overlapping clinicopathologic features that range in biologic potential from benign to overtly malignant. Even neoplasms with no metastatic potential may provide significant therapeutic challenges in this region due to the unique anatomy of the head and neck. This review will cover the following entities, highlighting important clinical aspects of each neoplasm and then focusing on their characteristic histomorphology, immunophenotype, and molecular alterations: nodular and cranial fasciitis, fibrous hamartoma of infancy, nasopharyngeal angiofibroma, nuchal-type and Gardner fibromas, desmoid fibromatosis, dermatofibrosarcoma protuberans and giant cell fibroblastoma, solitary fibrous tumor, inflammatory myofibroblastic tumor, low-grade myofibroblastic sarcoma, infantile fibrosarcoma, low-grade fibromyxoid sarcoma, and sclerosing epithelioid fibrosarcoma. While some of these neoplasms characteristically arise in the head and neck, others are rarely described in this anatomic region and may therefore be particularly difficult to recognize. Distinction between these entities, however, is crucial, particularly as the molecular pathogenetic basis for these neoplasms are being rapidly elucidated, in some instances allowing for targeted therapeutic approaches.

Myofibroblastic sarcoma of the breast. Report of a case induced by radiotherapys

Myofibroblastic sarcoma (MFS) is an uncommon tumor rarely located in the breast. Ionizing radiation is a carcinogen capable of inducing sarcomas through DNA damage. A 42-year-old woman was diagnosed with synchronous bilateral breast infiltrating ductal carcinoma with axillary lymph node metastases on the left side. After modified left radical mastectomy and simple right mastectomy, she underwent postoperative radiation with a total volume dose of 50 Gy that included the thoracic wall and the left axillary-supraclavicular region. After a latency period of 6 years and 4 months, the patient developed an MFS in the area of radiation (mammary upper outer quadrant). To our knowledge, only 11 cases of MFS have been previously published in the breast. The study of the 12 cases including the present one revealed that the ages of the patients ranged from 42 to 86 years (mean 60.3 years). There was a clear difference concerning sex (M:F, 1:5). The average duration of the lesion varied from 1 week to 8 months (mean 3.3 months). The size ranged from 2.2 to 22 cm (average 5.1 cm). The tumors showed frequent mitosis and areas of necrosis. The percentage of recurrences, metastasis, and death due to the tumor was 27.3%, 36.4%, and 27.3% respectively. MFS cases differ from those affecting extramammary regions. They are more common in females and show a greater degree of aggressiveness. Correct diagnosis of mammary MFS requires morphological and immunohistochemical study. We present for the first time a case of MFS of the breast induced by radiotherapy.

Low-grade Myofibroblastic sarcoma: clinical and imaging findings

Background

Low-grade myofibroblastic sarcoma (LGMS) is a rare type of tumor. Previous research has paid much attention to reporting pathological analyses of LGMS. However, only few systematic clinical and/or radiological studies have been conducted.

Methods

This study recruited 14 cases (8 males and 6 females) of LGMS. X-ray or computer tomography (CT) scan were performed on 11 cases. MRI was performed on 5 cases.

Results

X-Ray and CT scan: Five cases developed LGMS in bones, including 3 cases in the distal femur, 1 in the right shoulder blade, and another 1 in the right inferior ramus. Massive infiltrative and vermiform bone destruction with poorly-circumscribed lesion margins and partial soft tissue masses were observed. The other 9 cases were developed in soft tissues. Out of them, 4 cases presented slightly irregular hyper- or lower-density masses with poorly-circumscribed margins. 2 cases presented massive calcification and ossification. Significant enhancement was observed in 1 case, while no obvious enhancement was seen in the other 2 cases.

MRI: MR images of 5 cases revealed homogeneous iso- or hyper-signal intensity on T1WI and homogeneous or heterogeneous hyper-signal intensity on T2WI. Enhanced MRI revealed homogeneous enhancement in 2 cases and rim enhancement in 1 case.

Conclusions

Our findings show that LGMS is characterized by invasiveness, metastases and calcification. Different radiological tools should be employed to make an accurate diagnosis.

Myofibroblastic lesions in the oral cavity: Immunohistochemical and ultrastructural analysis

OBJECTIVE

To immunohistochemically characterize a group of oral myofibroblastic lesions (MLs) and to evaluate the ultrastructural features of myofibroblasts.

MATERIAL AND METHODS

Using a tissue microarray technique (TMA), cases of myofibroma (MF), of nodular fasciitis (NF), of desmoplastic fibroma (DF), and of myofibroblastic sarcoma (MS) from the Universidad Autónoma Metropolitana Xochimilco, and a Private Oral Pathology Service in Mexico City were stained with antibodies against alpha-smooth muscle actin (α-SMA), H-caldesmon, vimentin, desmin, β-catenin, CD34, anaplastic lymphoma protein kinase (ALK-1), and Ki-67.

RESULTS

Nineteen of the 22 MF cases, 2/5 of the NF cases, 1/10 of the DF cases, and 1/2 of the MS cases were positive for α-SMA. 1/2 of the MS cases were positive for desmin; 6/10 of the DF cases were positive for β-catenin, and 2 of the MF cases were positive for ALK-1. All of the MLs were positive for vimentin and negative for H-caldesmon and CD-34. The Ki-67 labeling index in all of the 8/22 MF, 3/5 NF, and 2/2 MS cases was ≥10%. For all of the MLs evaluated, ultrastructural analysis revealed spindle-shaped cells containing endoplasmic reticulum and peripheral actin filament bundles.

CONCLUSION

In certain myofibroblastic lesions, the use of auxiliary techniques (such as immunohistochemistry) can be critical for differential diagnosis.

The bottom line: MRI and CT findings of unusual rectal and perirectal pathology

Although common nonspecific symptoms (i.e., rectal bleeding, pelvic pressure, and change in bowel habits) are associated with rectal cancer, occasionally these are related to a different underlying disease. Over the past few years, considerable progress has been made in imaging of the rectum. Specifically, new magnetic resonance techniques and capabilities provide impressive high-resolution assessment of the rectal wall and enable evaluation and characterization of the perirectal tissues. This paper reviews imaging findings of uncommon causes of rectal and perirectal pathology that may be clinically confounded with rectal cancer. Radiologists need to be aware of uncommon pathologies in this region in order to facilitate optimal management decisions.

Low-grade myofibroblastic sarcoma of the orbit: A case report and literature review

RATIONALE

Low-grade myofibroblastic sarcoma (LGMS) is a malignant lesion composed of myofibroblasts. It is an uncommon tumor of unknown etiology that mainly develops in the bone or soft tissue and is most often reported in the head and neck, particularly in the tongue and oral cavity.

PATIENT CONCERNS

A 2-year-old girl, previously well and with no significant medical history or family history of other diseases, presented with a 2-week painless swelling of the right orbit.

DIAGNOSES

Preoperative computed tomography (CT) revealed a large homogeneous enhanced mass, 21 × 13 mm in size, located on lateral wall of the right orbit with bone absorption. The mass was resected and histopathological examination revealed LGMS of the orbit.

INTERVENTIONS

On May 2016, she underwent surgery without the additional postoperative treatment.

OUTCOMES

The patient's postoperative course was uneventful, and was discharged on the 6th day after surgery. During a year follow-up period, there was no recurrence of the postoperative CT. The patient and her family were satisfied with the result of the surgery.

LESSONS

Based on clinical characteristics and postoperative CT, we considered the mass may be a benign tumor. We completely resected along the capsule without an extensive surgical margin. However, postoperative histopathology diagnose LGMS, which shows a strong potential for local recurrence and vascular invasion. So we should close observation of the patient's symptoms and sign. If the tumor has invaded adjacent tissues, we will use adjuvant chemotherapy or radiotherapy.

Myofibroblastic, fibroblastic and myoid lesions of the breast

Myofibroblastic, fibroblastic and/or myoid lesions are rare in the breast but comprise the majority of mammary mesenchymal spindle cell lesions. Whereas most have similar features to their counterparts at extramammary sites, pseudoangiomatous stromal hyperplasia is considered a breast-specific myofibroblastic proliferation on the same spectrum as myofibroblastoma. Other lesions with myofibroblastic/fibroblastic differentiation include fibromatosis and nodular fasciitis, as well as more aggressive tumors such as the rarely reported myofibrosarcoma, inflammatory myofibroblastic tumor and fibrosarcoma. Lesions with myoid differentiation include benign leiomyoma, myoid hamartoma and leiomyomatous myofibroblastoma, but primary leiomyosarcoma and rhabdomyosarcoma may also rarely arise in the breast. Furthermore, fibroepithelial lesions and metaplastic carcinomas can demonstrate myoid metaplasia. Diagnosis can be challenging, particularly on core biopsy, but benign lesions with or without recurrence potential must be distinguished from more aggressive tumors, especially metaplastic carcinoma and phyllodes tumors. This article will review lesions with myofibroblastic, fibroblastic and myoid differentiation in the breast, with special emphasis on differential diagnosis.

Indolent growth of low-grade myofibroblastic sarcoma of the cheek mimics benign lesions: A case report and literature review

Low-grade myofibroblastic sarcoma (LGMS) is a neoplasm of the soft tissue characterized by myofibroblastic differentiation. This type of tumor has been observed in various sites in the whole body, but frequently occurs in the head and neck region. It typically presents as a slow-growing painless mass, which is often mistaken for a benign lesion due to its indolent growth; however, LGMS is a malignant neoplasm. In the present study, a 43-year-old female presented with a 14-mm LGMS lesion in the buccal subcutaneous tissues of the buccinator muscle. The patient had initially noticed the lesion 2-months prior to presenting at the hospital. Following biopsy, the tumor was surgically resected and no recurrence or metastasis was observed during a follow-up time of 2 years. To the best of our knowledge, this case is the first report of LGMS located in the buccal subcutaneous tissue of the buccinator muscle. The present study a literature review of 55 cases of this tumor type in the head and neck region was conducted, revealing that the indolent growth of these lesions may contribute to a delay in diagnosis. The average time between the onset of clinical symptoms and hospital admission is 3.9 months, and this form of tumor is frequently misdiagnosed as a benign lesion. Therefore, the present study suggests that an incisional biopsy may be performed to rule out LGMS when clinicians encounter patients with the aforementioned indolent lesions anywhere in the body. In addition, the avoidance of radiotherapy is recommended following resection of the LGMS tumor, as it may induce LGMS recurrence.

Recurrent Conjunctival Myofibrosarcoma Managed With Triple Application of Episcleral Brachytherapy

PURPOSE

To report a case of recurrent conjunctival myofibrosarcoma treated with wide surgical excision, cryotherapy, and triple sequential applications of episcleral brachytherapy.

METHODS

A single case of recurrent conjunctival myofibrosarcoma.

RESULTS

A 54-year-old man with a history of a renal transplant presented with a recurrent conjunctival tumor. Histopathologic diagnosis was established through immunohistochemistry. In total, 3 iodine radiation episcleral plaques were used over a period of 49 weeks. After cicatricial ectropion repair and cataract surgery, visual acuity was 20/20 at 4.5-year follow-up without evidence of recurrence or radiation retinopathy.

CONCLUSIONS

Myofibrosarcoma is a rare mesenchymal tumor that can present as ocular surface tumor. Final histopathologic diagnosis can be challenging, and immunohistochemistry is important for evaluation. Myofibrosarcoma should be considered in the clinical differential diagnosis of atypical ocular surface lesions and the histopathologic differential diagnosis of ocular spindle neoplasms.

Low-grade myofibroblastic sarcoma: A population-based study

OBJECTIVES/HYPOTHESIS

Low-grade myofibroblastic sarcoma (LGMS) is a rare entity that is described as having a predilection for occurring in the head and neck region. Here we analyze its demographics, clinic-pathologic, and survival characteristics.

STUDY DESIGN

Retrospective database analysis.

METHODS

A cohort from the Surveillance, Epidemiology, and End Results Program database of cases with LGMS between 2001 and 2012.

RESULTS

There were 49 cases with a 5-year overall survival of 71.6% and disease- specific survival of 76.3%. The majority of cases were in patients <60 years old, female, and white ethnicity. The most common sites were the extremities in 40.8% of cases followed by the head and neck region with 26.5% of cases. Multivariate analysis showed that only older age was significantly associated with worse survival (P < .05).

CONCLUSIONS

LGMS is uncommon in the United States and occurs most commonly in the extremities followed by the head and neck region, despite an existing characterization of a predilection for the head and neck region. Treatment most commonly involves surgery, but the optimal surgical extent and/or radiotherapy needs to be further investigated.

LEVEL OF EVIDENCE

2c Laryngoscope, 127:116-121, 2017.

Low-Grade Myofibroblastic Sarcoma in the Mandibular Canal: A Case Report

Low-grade myofibroblastic sarcoma (LGMS) represents an atypical myofibroblastic tumor characterized by a diffusely infiltrating pattern of spindle-shaped tumor cells. It was classified as a distinct soft tissue tumor by the World Health Organization in 2002. LGMS occurs mostly in adult patients and has a predilection for the head and neck region. So far, only a few cases of LGMS located in the mandible have been reported. Aggressive surgical resection with clear margins is the primary treatment for LGMS. Because of its rarity, reports of radiation therapy are limited, and the therapeutic effect is still controversial. We present the case of an 8-year-old girl with LGMS of the mandibular canal to highlight the clinical features and rarity and to improve the understanding of the therapeutic effect of radiotherapy on LGMS.

Low-grade myofibroblastic sarcoma arising in fibroadenoma of the breast-A case report

BACKGROUND

Myofibroblastic sarcoma or myofibrosarcoma is a malignant tumor of myofibroblasts and known to develop rarely in the breast, but its underlying lesion and tumor cell origin have never been reported yet.

CASE PRESENTATION

A 61-year-old female presented with a gradually growing breast mass with well-demarcated ovoid nodular shape. The tumor was histologically characterized by fascicular-growing spindle cell proliferation with large areas of hyalinized fibrosis and focally ductal epithelial remnants embedded in myxoid stroma, mimicking a fibroadenomatous lesion. It had frequent mitoses of 5-16/10 high-power fields, hemorrhagic necrosis, and focally pericapsular invasion. The spindle cells were diffusely immunoreactive for fibronectin, smooth muscle actin, and calponin, which suggest a myofibroblastic origin. Multiple irregularly thickened vessels with medial or pericytic cell proliferation were found to be merged with the intrinsic tumor cells. The tumor could be diagnosed low-grade myofibroblastic sarcoma arising in an old fibroadenoma.

CONCLUSION

We report a case of a low-grade mammary myofibrosarcoma that showed a background lesion of fibroadenoma first in the worldwide literature and suggest the pericytes or medial muscle cells of the intratumoral vessels as the cell origin of the myofibroblastic sarcoma.

LOW-GRADE MYOFIBROBLASTIC SARCOMA OF THE LARYNX: CASE REPORT AND REVIEW OF LITERATURE

Low-grade myofibroblastic sarcoma (LGMS) is a very rare, atypical myofibroblastic tumor with fibromatosis-like features with predilection mostly in head and neck region. LGMS occurs primarily in adult patients with a slight male predominance. Only few cases of LGMS affecting the larynx have been reported in literature to this date. We describe a case of low-grade myofibroblastic sarcoma of the larynx in a 40-year-old male patient. The clinicopathological characteristics, immunohistochemical findings and treatment are discussed.

Conjunctival Leiomyosarcoma: A Report of Two Cases

PURPOSE

Leiomyosarcoma is a common soft tissue tumor in the body. However, ocular leiomyosarcoma is rather uncommon. Herein, we describe the clinical and histopathological features of two cases of conjunctival leiomyosarcoma. There have only been three previously documented cases of conjunctival leiomyosarcoma.

RESULTS

A 34-year-old male presented with a 2-year history of a whitish mass in the right eye. He underwent an incisional biopsy of the mass, which supported the diagnosis of leiomyosarcoma on histopathological examination. Computed tomography showed orbital extension of the mass, following which he underwent an eyelid sparing orbital exenteration of the right side. The second case was that of a 39-year-old male, who had a history of a whitish limbal mass, which had been previously excised elsewhere. The pre-operative clinical photographs and histopathology slides of the excised mass were reviewed. A histopathological diagnosis of conjunctival leiomyosarcoma was established and due to base positivity, he was treated with plaque radiotherapy. Both the cases showed no tumor recurrence or systemic metastasis at one-year follow-up.

CONCLUSION

Primary conjunctival leiomyosarcoma is uncommon. Appropriate treatment of the tumor is associated with good prognosis.

Low-grade myofibroblastic sarcomas of the maxilla

Low-grade myofibroblastic sarcoma (LGMS) is a distinct mesenchymal myofibroblastic malignancy. The tumor may occur at a variety of sites, but is particularly associated with the head and neck. Of the two maxillary sarcomas that were analyzed in the present study, one was misdiagnosed as an inflammatory myofibroblastic tumor during pre-operative excision biopsy, and later presented with a different immunophenotype upon recurrence. Representative paraffin blocks from formalin-fixed tissues were selected from each patient and designated as case 1 and case 2. Immunohistochemical studies were performed on 3-μm thick sections using primary antibodies against α-smooth muscle actin (α-SMA), muscle-specific actin (MSA), desmin, vimentin, calponin, h-caldesmon, fibronectin, cytokeratin, cluster of differentiation 34 (CD34), S-100 protein, anaplastic lymphoma kinase (ALK), epithelial membrane antigen (EMA) and Ki-67. Immunohistochemistry was performed using the streptavidin-biotin-peroxidase complex method. The tumor cells from the two maxillary LGMSs, including the recurrent lesion, were positive for vimentin and fibronectin, and negative for S-100 protein, CD34, EMA, h-caldesmon, ALK, MSA and calponin. The tumor cells from case 1 demonstrated positive staining for α-SMA protein and negative staining for desmin. By contrast, the tumor cells from the primary lesion in case 2 presented with negative staining for α-SMA and positive staining for desmin, while the cells of the recurrent lesion were α-SMA-positive and desmin-negative. The present study concluded that cases of LGMS with immunoprofile alterations are predictive of relatively poor prognoses.

Abnormal liver function induced by myofibroblastic sarcoma infiltrating the liver: A case report

Myofibroblastic sarcoma (MS) is a rare disease, which most frequently occurs in the head, neck and extremities. To the best of our knowledge, although a small number of studies have reported MS of the oral cavity, maxilla, tonsil, thyroid and tongue, MS of the liver and subsequent disabled liver function has not been previously reported. This study presents the case of a 38 year old female initially diagnosed and treated for a mass in the retroperitoneal region, who was subsequently diagnosed with MS of the liver three months following preliminary surgical treatment. The patient refused further treatment and was lost to follow-up three months after discharge from the hospital. Clinical, biochemical and imaging observations, as well as pathological manifestations of the patient in the present case are discussed with the aim of increasing the knowledge of MS of the liver.

Multicentric myofibroblastic sarcoma

We report a case of synchronous, multicentric low-grade myofibroblastic sarcoma presenting in a 62-year-old man. He initially presented with inflammatory symmetric polyarthritis and adhesive capsulitis of his shoulder and hips bilaterally and did not respond to a trial of disease modifying antirheumatic drugs. Over a period of several years he developed progressive restriction of both knees and nodules on his hands, both knees and back. A biopsy of the nodule on his back was inconclusive and subsequent biopsies on his left and then right knee revealed a spindle cell neoplasm with an infiltrative growth pattern, mitotic figures, positive immunostaining for smooth muscle actin and focal myxoid change consistent with myofibroblastic sarcoma. While myofibroblastic sarcoma has been known to metastasise, to our knowledge, a multifocal presentation of this tumour has not been described previously.

Long-term disease-free survival after radical local excision of low-grade myofibroblastic sarcoma of the vulva

•A second case of low-grade myofibroblastic sarcoma of the vulva.•Six-year follow-up with no evidence of disease after radical local excision.•Adequate margin resection is important.