A case of cutaneous low-grade myofibroblastic sarcoma

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 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.

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.

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.

Low-grade myofibroblastic sarcoma of the mandible: a case report

INTRODUCTION

Low-grade myofibroblastic sarcoma is a rare entity, which mostly develops in the soft tissues of the head and neck. Within the oral cavity lingual lesions are the most common. It tends to recur locally rather than to metastasise.

CASE PRESENTATION

We present a 54-year-old man with a one-year history of buccal oedema. He also had arterial hypertension and clinical examination revealed distension of the left mandibular ramus with laminar deflection in the area of the retromolar triangle.

CONCLUSION

We present a rare intramandibular encapsulated lesion that caused diagnostic difficulties. Our diagnostic methods included immunohistochemistry and molecular investigations. We emphasise the uncommon location of this tumour type.

Low-grade myofibroblastic sarcoma of the piriform fossa: a case report with a literature review of a tumour with a predilection for the head and neck

A low-grade myofibroblastic sarcoma was removed from the pyriform fossa of a 44-year-old man. It recurred 4 years later and was removed radically through an incision in the neck. There has been no further recurrence after 11 years.

Unusual sarcomatoid neoplasm of the lung suggesting a myofibrosarcoma

Myofibrosarcoma is a rare neoplasm that occurs mainly in the head and neck region and extremities of middle-aged patients. It often appears as a low-grade sarcoma and rarely metastasizes. We report the case of a 47-year-old male patient with a malignant mesenchymal pulmonary tumor affecting almost the entire lower left lobe. Clinically suggestive for a lung carcinoma, the tumor showed typical features of a myofibrosarcoma. A major spindle cell component was observed being positive for smooth-muscle actin, calponin, and vimentin, while stainings for desmin, h-caldesmon, alkaline phosphatase (ALK), and extensively studied cytokeratins were negative. Striking was a strong infiltrate with neutrophilic and eosinophilic granulocytes. DNA cytometry revealed aneuploidy with a peak in the near triploid range. Comparative genomic hybridization demonstrated multiple DNA gains and losses correlating with an aggressive clinical course. Shortly after resection of the primary tumor, the patient showed multiple distant metastases in the contralateral lung, the mediastinal lymph nodes, the left adrenal gland, and the pectoral and deltoid muscle, which responded well to chemotherapy. The case report will discuss the evidence for the final diagnosis of a primary pulmonary myofibrosarcoma and the differential diagnosis of sarcomatoid tumors of the lung.

Low-grade myofibroblastic sarcoma of the distal phalanx

Low-grade myofibroblastic sarcoma is a recently defined tumor that is part of the spectrum of malignant mesenchymal tumors, showing features of myofibroblastic differentiation. These tumors occur most commonly in the head and neck regions, especially in the tongue, and less frequently in the limbs, trunk, and abdominal/pelvic cavity. We describe a 51-year-old woman with a low-grade myofibroblastic sarcoma. The distal phalanx of the finger was amputated with a clear surgical margin. The treatment of this tumor should include a simple local excision with free surgical margins and a long clinical follow-up period with imaging studies. At the 28-month follow-up evaluation the patient was free from this tumor.