Skip to main content

Main menu

  • Home
  • Content
    • First Release
    • Current
    • Archives
    • Collections
    • Audiovisual Rheum
    • COVID-19 and Rheumatology
  • Resources
    • Guide for Authors
    • Submit Manuscript
    • Payment
    • Reviewers
    • Advertisers
    • Classified Ads
    • Reprints and Translations
    • Permissions
    • Meetings
    • FAQ
    • Policies
  • Subscribers
    • Subscription Information
    • Purchase Subscription
    • Your Account
    • Terms and Conditions
  • About Us
    • About Us
    • Editorial Board
    • Letter from the Editor
    • Duncan A. Gordon Award
    • Privacy/GDPR Policy
    • Accessibility
  • Contact Us
  • JRheum Supplements
  • Services

User menu

  • My Cart
  • Log In

Search

  • Advanced search
The Journal of Rheumatology
  • JRheum Supplements
  • Services
  • My Cart
  • Log In
The Journal of Rheumatology

Advanced Search

  • Home
  • Content
    • First Release
    • Current
    • Archives
    • Collections
    • Audiovisual Rheum
    • COVID-19 and Rheumatology
  • Resources
    • Guide for Authors
    • Submit Manuscript
    • Payment
    • Reviewers
    • Advertisers
    • Classified Ads
    • Reprints and Translations
    • Permissions
    • Meetings
    • FAQ
    • Policies
  • Subscribers
    • Subscription Information
    • Purchase Subscription
    • Your Account
    • Terms and Conditions
  • About Us
    • About Us
    • Editorial Board
    • Letter from the Editor
    • Duncan A. Gordon Award
    • Privacy/GDPR Policy
    • Accessibility
  • Contact Us
  • Follow jrheum on Twitter
  • Visit jrheum on Facebook
  • Follow jrheum on LinkedIn
  • Follow jrheum on YouTube
  • Follow jrheum on Instagram
  • Follow jrheum on RSS
LetterLetter

A Rare Cause of Foot Swelling Mimicking Tenosynovitis

NEIL MO, VUN LIM, JONATHAN J. GREGORY and PAUL COOL
The Journal of Rheumatology September 2010, 37 (9) 1977; DOI: https://doi.org/10.3899/jrheum.100264
NEIL MO
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • For correspondence: nmo@doctors.net.uk
VUN LIM
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
JONATHAN J. GREGORY
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
PAUL COOL
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site
  • Article
  • Figures & Data
  • Info & Metrics
  • References
  • PDF
  • eLetters
PreviousNext
Loading

To the Editor:

Tenosynovitis occurring over the digital extensors of the extremities is a common cause of soft tissue swelling seen by the rheumatologist. We describe a case of long-standing soft tissue swelling on the dorsum of the foot. This was initially attributed to tenosynovitis but gradually became more edematous. Indeterminate radiological findings prompted a biopsy, which revealed an unusual low-grade tumor with metastatic potential. We highlight the importance of obtaining a soft-tissue biopsy if there is any degree of diagnostic uncertainty after radiological imaging.

A 54-year-old woman presented with a 12-month history of painful swelling over the dorsum of the right foot. The swelling varied in size, the patient describing discrete episodes of more pronounced swelling for up to 2 weeks. There was a family history of rheumatoid arthritis in the mother and sister. The patient did not experience undue weight loss or loss of appetite. Clinical examination revealed a soft, fluctuant swelling over the digital extensor tendons of the right foot (Figure 1). This measured 3–4 cm in size and was mildly tender to palpation. Rheumatoid factor and antinuclear antibody were negative. C-reactive protein and erythrocyte sedimentation rate were within normal range. The possibility of tenosynovitis was noted, with an ultrasound scan requested to confirm this.

Figure 1.
  • Download figure
  • Open in new tab
  • Download powerpoint
Figure 1.

Soft tissue swelling in right foot.

The ultrasound showed a solid hyperemic mass with cystic elements, raising concern for the mass being neoplastic. Gadolinium enhanced magnetic resonance imaging (MRI) showed a diffuse area of abnormal signal confined to subcutaneous fat with moderate patchy enhancement. The mass did not appear to involve the extensor tendons (Figure 2). Although the appearances were fairly nonspecific, in view of the long history and persistent unilateral involvement, a referral to the regional sarcoma service was made. The patient underwent Trucut biopsies for histological examination, which confirmed an acral myxoinflammatory fibrosarcoma (AMFS). The treatment options consisted of wide local excision with reconstructive surgery or below-knee amputation. After discussion with the patient, she chose below-knee amputation to minimize the risk of local recurrence.

Figure 2.
  • Download figure
  • Open in new tab
  • Download powerpoint
Figure 2.

Gadolinium enhanced MRI showing patchy enhancement of swelling.

Soft tissue sarcomas can be difficult to distinguish from benign lesions on history and clinical examination findings alone. AMFS is part of a group of soft tissue tumors that have been recognized to mimic benign lesions1. AMFS is a low-grade tumor with a predilection for the extremities and tends to occur in middle-aged patients. It is rare, with fewer than 200 cases reported in the literature2. When situated over joints or tendons, its soft consistency may resemble synovial proliferation or tenosynovitis. Although the tumor tends to feel more firm than a benign lipoma, this may be difficult to distinguish clinically. It can also be clinically and radiographically mistaken for an atypical ganglion. AMFS is usually a painless tumor and the pain experienced by our patient may have been due to compression by footwear. Radiological clarification of the swelling is important but even MRI studies have demonstrated difficulties in distinguishing this tumor from tenosynovitis3. Histological appearances of the tumor are unusual. Large epithelioid cells with vesicular nuclei are commonly present and closely resemble the Reed-Sternberg cells seen in Hodgkin’s lymphoma.

In most cases, the tumor will be confined to the dermis, underlying fascia, tendons, and ligaments (as in our patient). Muscle involvement and local bone infiltration is rare. Metastases are also rare but well described, as are tumor related deaths4. Surgical excision is the only definitive treatment, with many patients being treated with local excision only, depending on the site and extent of the tumor. Recurrence after local excision is uncommon, provided that adequate margins can be achieved.

Although many soft tissue swellings can be diagnosed clinically, our case demonstrated that a rare tumor can masquerade as a seemingly benign swelling. The protracted time course and slow-growing nature of the tumor may dissuade the clinician from a sinister pathology. However, clinical presentation of a persistent unilateral swelling, in the absence of any risk factors for foot edema, should prompt clinical suspicion of the possibility of an unusual pathology. Our case highlights the importance of confirming the nature of any soft tissue swelling with further investigations and biopsy as appropriate.

    REFERENCES

    1. 1.↵
      1. Hollowood K,
      2. Fletcher CD
      . Soft tissue sarcomas that mimic benign lesions. Semin Diagn Pathol 1995;12:87–97.
      OpenUrlPubMed
    2. 2.↵
      1. Kovarik CL,
      2. Barrett T,
      3. Auerbach A,
      4. Cassarino DS
      . Acral myxoinflammatory fibroblastic sarcoma: case series and immunohistochemical analysis. J Cutan Pathol 2008;35:192–6.
      OpenUrlPubMed
    3. 3.↵
      1. Narvaez JA,
      2. Martinez S,
      3. Dodd LG,
      4. Brigman BE
      . Acral myxoinflammatory fibroblastic sarcomas: MRI findings in four cases. AJR Am J Roentgenol 2007;188:1302–5.
      OpenUrlCrossRefPubMed
    4. 4.↵
      1. Hassanein AM,
      2. Atkinson SP,
      3. Al-Quran SZ,
      4. Jain SM,
      5. Reith JD
      . Acral myxoinflammatory fibroblastic sarcomas: are they all low-grade neoplasms? J Cutan Pathol 2008;35:186–91.
      OpenUrlPubMed
    PreviousNext
    Back to top

    In this issue

    The Journal of Rheumatology
    Vol. 37, Issue 9
    1 Sep 2010
    • Table of Contents
    • Table of Contents (PDF)
    • Index by Author
    • Editorial Board (PDF)
    Print
    Download PDF
    Article Alerts
    Sign In to Email Alerts with your Email Address
    Email Article

    Thank you for your interest in spreading the word about The Journal of Rheumatology.

    NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

    Enter multiple addresses on separate lines or separate them with commas.
    A Rare Cause of Foot Swelling Mimicking Tenosynovitis
    (Your Name) has forwarded a page to you from The Journal of Rheumatology
    (Your Name) thought you would like to see this page from the The Journal of Rheumatology web site.
    CAPTCHA
    This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
    Citation Tools
    A Rare Cause of Foot Swelling Mimicking Tenosynovitis
    NEIL MO, VUN LIM, JONATHAN J. GREGORY, PAUL COOL
    The Journal of Rheumatology Sep 2010, 37 (9) 1977; DOI: 10.3899/jrheum.100264

    Citation Manager Formats

    • BibTeX
    • Bookends
    • EasyBib
    • EndNote (tagged)
    • EndNote 8 (xml)
    • Medlars
    • Mendeley
    • Papers
    • RefWorks Tagged
    • Ref Manager
    • RIS
    • Zotero

     Request Permissions

    Share
    A Rare Cause of Foot Swelling Mimicking Tenosynovitis
    NEIL MO, VUN LIM, JONATHAN J. GREGORY, PAUL COOL
    The Journal of Rheumatology Sep 2010, 37 (9) 1977; DOI: 10.3899/jrheum.100264
    del.icio.us logo Digg logo Reddit logo Twitter logo CiteULike logo Facebook logo Google logo Mendeley logo
    • Tweet Widget
    • Facebook Like
    • Google Plus One
    Bookmark this article

    Jump to section

    • Article
      • REFERENCES
    • Figures & Data
    • Info & Metrics
    • References
    • PDF
    • eLetters

    Related Articles

    Cited By...

    More in this TOC Section

    • Does the BNT162b2 Vaccine Trigger Antimelanoma Differentiation-Associated Gene 5 Antibody–Positive Interstitial Lung Disease?
    • Duration of Steroid Therapy and Temporal Artery Biopsy Positivity in Giant Cell Arteritis: A Retrospective Cohort Study
    • Desk Rejections: Not Without Due Deliberation
    Show more Letters

    Similar Articles

    Content

    • First Release
    • Current
    • Archives
    • Collections
    • Audiovisual Rheum
    • COVID-19 and Rheumatology

    Resources

    • Guide for Authors
    • Submit Manuscript
    • Author Payment
    • Reviewers
    • Advertisers
    • Classified Ads
    • Reprints and Translations
    • Permissions
    • Meetings
    • FAQ
    • Policies

    Subscribers

    • Subscription Information
    • Purchase Subscription
    • Your Account
    • Terms and Conditions

    More

    • About Us
    • Contact Us
    • My Alerts
    • My Folders
    • Privacy/GDPR Policy
    • RSS Feeds
    The Journal of Rheumatology
    The content of this site is intended for health care professionals.
    Copyright © 2022 by The Journal of Rheumatology Publishing Co. Ltd.
    Print ISSN: 0315-162X; Online ISSN: 1499-2752
    Powered by HighWire