[Skip to Content]
[Skip to Content Landing]

Parotid Mass in an 81-Year-Old Woman

Educational Objective
Based on this clinical scenario and the accompanying image, understand how to arrive at a correct diagnosis.
1 Credit CME

An 81-year-old woman presented with a 3-month history of a slow-growing mass in her left cheek. She denied having any symptoms, tenderness, numbness, or facial nerve weakness. Physical examination revealed a mass in the buccinator space that was smooth, was nontender to palpation, and had no overlying cutaneous changes. A contrast-enhanced maxillofacial computed tomography scan demonstrated a 1.8 × 1.8 × 1.9-cm rounded, well-circumscribed lesion at the anterior aspect of the left masticator space (Figure 1). The mass was abutting the parotid duct, which did not appear dilated, and appeared to have a peripheral rim of hyperenhancing soft tissue with a central cystic/necrotic component. Results of ultrasound-guided fine-needle aspiration revealed rare epithelial cells with degenerative changes and inflammatory cells present. Findings from a core biopsy demonstrated a spindle cell neoplasm of uncertain origin. On immunostaining, spindle cells were CK8/18, S100, and SOX10 negative; myosin and smooth muscle actin (SMA) negative; and CD31 negative. However, STAT6 staining was diffusely positive.

Please finish quiz first before checking answer.

You answered correctly!

Read the answer below and download your certificate.

You answered incorrectly.

Read the discussion below and retake the quiz.

D. Solitary fibrous tumor

Solitary fibrous tumors (SFTs) are rare, spindle-cell neoplasms of mesenchymal origin that preferentially arise in serosal membranes, intracranial and spinal cord meninges, and the extremities.1 While pleural SFTs are most common, an estimated 6% to 18% of SFTs occur in the head and neck region, most frequently involving the oral cavity, sinonasal tract, orbit, or salivary glands.2 Peak incidence is in middle-aged adults (median age, 51 years); there is no sex predilection. Patients most commonly present with a small (<5 cm), painless, slow-growing mass, with or without site-related compressive symptoms. Standard of care is wide surgical resection; however, rates of positive surgical margins are high, and postoperative radiation therapy may be considered.2 Under the 2020 World Health Organization Classification of Soft Tissue and Bone Tumors, SFTs are categorized as fibroblastic/myofibroblastic neoplasms with intermediate—rarely metastasizing—biological behavior, and multiple case series have described the indolent nature of SFT.13 However, the clinical behavior of individual tumors is notoriously difficult to predict: there is a predilection for late local recurrence in 5% to 40% of patients,1 with varying reports of median time to recurrence between 37 and 120 months.1 Several risk-assessment schema have been proposed to predict the behavior of SFT (ie, risk of metastasis, risk of recurrence, disease-free and overall survival).1,4 These schema consider factors such as patient age, tumor size, depth of location, cellularity, pleomorphism, and mitotic rate/index to stratify SFTs as very low, low, moderate/intermediate, or high risk.1,4

Survey Complete!

Sign in to take quiz and track your certificates

Buy This Activity

JN Learning™ is the home for CME and MOC from the JAMA Network. Search by specialty or US state and earn AMA PRA Category 1 Credit(s)™ from articles, audio, Clinical Challenges and more. Learn more about CME/MOC

CME Disclosure Statement: Unless noted, all individuals in control of content reported no relevant financial relationships. If applicable, all relevant financial relationships have been mitigated.

Article Information

Corresponding Author: Karthik Rajasekaran, MD, Department of Otorhinolaryngology–Head and Neck Surgery, University of Pennsylvania, 800 Walnut St, 18th Floor, Philadelphia, PA 19107 (karthik.rajasekaran@pennmedicine.upenn.edu).

Published Online: August 11, 2022. doi:10.1001/jamaoto.2022.2249

Conflict of Interest Disclosures: None reported.

Additional Contributions: We thank the patient for granting permission to publish this information.

References
1.
Demicco  EG , Park  MS , Araujo  DM ,  et al.  Solitary fibrous tumor.   Mod Pathol. 2012;25(9):1298-1306.PubMedGoogle ScholarCrossref
2.
Ronchi  A , Cozzolino  I , Zito Marino  F ,  et al.  Extrapleural solitary fibrous tumor.   Ann Diagn Pathol. 2018;34:142-150.PubMedGoogle ScholarCrossref
3.
Sbaraglia  M , Bellan  E , Dei Tos  AP .  The 2020 WHO Classification of Soft Tissue Tumours.   Pathologica. 2021;113(2):70-84.PubMedGoogle ScholarCrossref
4.
Pasquali  S , Gronchi  A , Strauss  D ,  et al.  Resectable extra-pleural and extra-meningeal solitary fibrous tumours.   Eur J Surg Oncol. 2016;42(7):1064-1070.PubMedGoogle ScholarCrossref
5.
Bauer  JL , Miklos  AZ , Thompson  LDR .  Parotid gland solitary fibrous tumor.   Head Neck Pathol. 2012;6(1):21-31.PubMedGoogle ScholarCrossref
6.
O’Regan  EM , Vanguri  V , Allen  CM , Eversole  LR , Wright  JM , Woo  SB .  Solitary fibrous tumor of the oral cavity.   Head Neck Pathol. 2009;3(2):106-115.PubMedGoogle ScholarCrossref
7.
Doyle  LA , Vivero  M , Fletcher  CD , Mertens  F , Hornick  JL .  Nuclear expression of STAT6 distinguishes solitary fibrous tumor from histologic mimics.   Mod Pathol. 2014;27(3):390-395.PubMedGoogle ScholarCrossref
8.
LeBlanc  RE , Taube  J .  Myofibroma, myopericytoma, myoepithelioma, and myofibroblastoma of skin and soft tissue.   Surg Pathol Clin. 2011;4(3):745-759.PubMedGoogle ScholarCrossref
9.
Gopalakrishnan  V , Amini  B , Wagner  MJ ,  et al.  Synovial sarcoma of the head and neck.   Sarcoma. 2017;2017:2016752.PubMedGoogle Scholar
10.
Obeidin  F , Alexiev  BA . Synovial sarcoma. PathologyOutlines.com. Accessed July 7, 2022. https://www.pathologyoutlines.com/topic/softtissuesynovialsarc.html
Close
Want full access to the AMA Ed Hub?
After you sign up for AMA Membership, make sure you sign in or create a Physician account with the AMA in order to access all learning activities on the AMA Ed Hub
Buy this activity
Close
Want full access to the AMA Ed Hub?
After you sign up for AMA Membership, make sure you sign in or create a Physician account with the AMA in order to access all learning activities on the AMA Ed Hub
Buy this activity
Close
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Education Center Collection Sign In Modal Right
Close

Name Your Search

Save Search
With a personal account, you can:
  • Access free activities and track your credits
  • Personalize content alerts
  • Customize your interests
  • Fully personalize your learning experience
Close
Close

Lookup An Activity

or

My Saved Searches

You currently have no searches saved.

Close

My Saved Courses

You currently have no courses saved.

Close