Ischemic fasciitis conversion to myxofibrosarcoma: A case report

Abstract

Introduction

Ischemic fasciitis is a rare pseudosarcomatous fibroblastic lesion. It is considered benign and generally occurs in the elderly. Long-term follow-up is rare therefore; the natural history is largely unknown. It is excised without specific attention to margins.

Case presentation

We present a case of a 94-year-old female with ischemic fasciitis on the shoulder for which we have three years of follow-up. During this time, multiple re- excisions for recurrence were required. This lesion eventually progressed to myxofibrosarcoma.

Clinical discussion

We suggest ischemic fasciitis may be a precursor to malignancy. Ischemic fasciitis itself is noted to have features similar to sarcoma on histopathology. Simple excision of ischemic fasciitis without margins may be inadequate therapy.

Conclusion

Ischemic fasciitis or pseudosarcomatous fibroblastic lesion and myxofibrosarcoma have many histological similarities. A pseudosarcomatous fibroblastic lesion may be a precursor to myxofibrosarcoma and we recommend complete excision with negative margins at the initial treatment to prevent a recurrence.

Highlights

• •Ischemic fasciitis is a rare pseudosarcomatous fibroblastic lesion.
• •The natural history is largely unknown. It is excised without specific attention to margins.
• •Conversion of lesion to myxofibrosarcoma.
• •Pseudosarcomatous fibroblastic lesion may be a precursor to myxofibrosarcoma.

1. Background

Ischemic fasciitis is a rare pseudosarcomatous fibroblastic lesion. Typical patients are elderly often immobile or debilitated. These lesions appear as soft tissue masses overlying bony prominences [1]. The soft tissue overlying the shoulder is the most common site, followed by the chest wall over ribs, sacrococcygeal area, and the greater trochanter. It was first characterized by Montgomery et al. as “atypical decubital hyperplasia” and pathogenesis of the lesion was hypothesized to be due to pressure-induced ischemia. This has since been challenged and it is being described as a reactive process [1]. Defining microscopic pathologic findings include a zonal pattern with a central zone of liquefactive or focally coagulative necrosis [2]. Studies have shown varying degrees of recurrence including Montgomery et al. reporting three cases of recurrence out of 21 and a study by Liegl et al. reporting only one recurrence in a cohort of 44 patients [1], [2]. Follow up is often limited as this patient population is elderly.

We present a case of a patient with a lesion initially diagnosed as ischemic fasciitis with recurrent lesions significant for myxofibrosarcoma. Ischemic fasciitis is a rare lesion that is described in the literature as benign. Our case represents a conversion to myxofibrosarcoma. This work was completed following the SCARE criteria [3].

2. Case presentation

This patient didn't report any other significant medical, surgical, and drug history other than what will be described in this case report. Our patient noticed a right shoulder mass at age 94 three months after a stroke which limited her mobility. One year later, a dermatologist excised the mass. The pathology report was significant for a 3 × 2.9 × 0.7 cm mass diagnosed as ischemic fasciitis. Microscopic description demonstrated a dense fibrotic and edematous area containing focal mucin and “tissue-culture” type fibroblasts. At age 96, the mass recurred (Fig. 1). The patient felt this was limiting her arm movements and requested excision. On clinical exam, a six centimeter rubbery, well-defined, non-tender mass was palpable. It was fixed to the musculature of the shoulder. She was taken to the operating room for excision of the mass. A 6.5 × 5 × 2.5 cm mass was excised. Pathology evaluation demonstrated extensive myxoid changes separated by dense fibrous tissue and focal cystic degenerative changes without nuclear pleomorphism or mitosis but few scattered mast cells (Fig. 2). A final diagnosis of benign fibromyxoid nodules with cystic degenerative changes, negative for malignancy was made. The patient returned eight months later at age 97 with a recurrent mass in the area of the previous excision, which had been growing rapidly the eight weeks prior to evaluation. Again the patient wished to proceed with excision as the mass was painful and limiting arm movements. In the operating room, a seven-centimeter mass was excised. The microscopic evaluation demonstrated a hypercellular myxoid neoplasm with areas of loose fascicular growth, moderate to high cytologic atypia, geographic necrosis, and areas of more epithelioid cells with vesicular chromatin and prominent nucleoli (Fig. 3). The lesional cells showed weak CD34 activity. These findings were consistent with high-grade myxofibrosarcoma.

Fig. 1.

Right posterior shoulder mass at time of initial surgical evaluation.

Fig. 2.

Histology from initial excision of recurrent mass, ischemic fasciitis.

Fig. 3.

Histology from second re-excision consistent with myxofibrosarcoma.

After receiving the diagnosis of myxofibrosarcoma, the patient was offered re-excision for better margins and consultation with radiation oncology. She initially elected to forego additional treatment. She returned eight months later with recurrent nodules at the same site.

Multiple nodules were excised in the operating room, once again positive for recurrent myxofibrosarcoma (Fig. 4, Fig. 5). After consultation with radiation oncology, she elected to proceed with radiation therapy after surgical excision.

Fig. 4.

Multiple recurrent nodules of myxofibrosarcoma at time of last excision.

Fig. 5.

Specimens after last excision, multiple recurrent nodules.

3. Discussion

Although rare, ischemic fasciitis is recognized as a benign pseudosarcomatous fibroblastic lesion. In this case, our patient had a history of a lesion diagnosed as ischemic fasciitis and subsequent progression to myxofibrosarcoma. A review of the histology slides from each excision that occurred at our facility revealed a trend of increasing hypercellularity. We suggest ischemic fasciitis may be a precursor to malignancy. Ischemic fasciitis itself is noted to have features similar to sarcoma on histopathology [4].

Our literature review did not identify any other reports of this rare benign lesion progressing to myxofibrosarcoma. This could be a result of difficulty with long-term follow-up in an elderly population. The patient population with ischemic fasciitis is elderly, with a peak incidence in the eighth and ninth decade of life [5]. In our case, we were able to have a consistent follow-up with our patient over several years.

Myxofibrosarcomas is treated with wide resection of the lesions with two-centimeter margins, and radiation therapy for high-grade lesions [6]. The natural history of ischemic fasciitis over time is largely unknown. If these lesions are precursors to sarcoma as in our case, we suggest that simple excision of ischemic fasciitis without margins may be inadequate therapy. As our population ages, we expect the incidence of ischemic fasciitis to increase. Although recurrence is uncommon with ischemic fasciitis, there still are documented cases of recurrence due to inadequate margins [7]. Given the lack of long-term follow-up in patients with ischemic fasciitis, strong consideration needs to be made for obtaining adequate margins at the time of initial excision along with close follow-up for surveillance of recurrence.

4. Conclusion

A 96-year-old female was treated for a recurrent right posterior shoulder mass that was originally diagnosed as ischemic fasciitis. After multiple re-excisions for recurrent masses in the area, pathology became significant for myxofibrosarcoma. A literature review showed that ischemic fasciitis recurring as a myxofibrosarcoma is uncommon. Given our patient's conversion to myxofibrosarcoma, we suggest obtaining clear margins at the time of initial excision.

Provenance and peer review

Not commissioned, externally peer-reviewed.

Funding

No sources of funding.

Ethical approval

This case report was approved by our institutional review board.

Consent

Written informed consent was obtained from the patient for publication of this case report and accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Research registration

Not applicable.

Guarantor

Dr. Constanze Rayhrer.

CRediT authorship contribution statement

Dr. Rayhrer: Writing original draft, visualization, project administration; Writing original draft; Janelle Lopez: Writing, review, editing, submission.

Declaration of competing interest

Nothing to declare.