Lymph nodes & spleen, nonlymphoma
Ectopic tissue / inclusions
Smooth muscle
Topic Completed: 1 September 2014
Minor changes: 22 March 2021
Copyright: 2003-2021, PathologyOutlines.com, Inc.
PubMed Search: Smooth muscle [title] lymph nodes
Table of Contents
Definition / general | Sites | Etiology | Clinical features | Diagnosis | Case reports | Gross description | Microscopic (histologic) description | Microscopic (histologic) images | Positive stains | Negative stains | Differential diagnosis | Additional referencesCite this page: Balakrishna J. Smooth muscle. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lymphnodessmoothmuscle.html. Accessed October 28th, 2021.
Definition / general
- Topic discusses the presence of smooth muscle within the capsule and hilum of normal lymph nodes
- Common, incidental finding in lymph nodes of hilar smooth muscle proliferation, more commonly in males than females (Virchows Arch A Pathol Anat Histopathol 1985;406:261)
Sites
- Superficial, inguinal and axillary lymph nodes are most commonly involved
Etiology
- Suggested etiological factors include back pressure in efferent lymphatics, local inflammation
Clinical features
- Asymptomatic, with no apparent clinical significance, but may have enlarged lymph nodes
Diagnosis
- Biopsy
- Immunohistochemistry for smooth muscle to confirm
Case reports
- 6 year old boy with intranodal leiomyoma (Pediatr Dev Pathol 2014;17:118)
Gross description
- Enlarged lymph nodes with firm, tan cut surface
Microscopic (histologic) description
- Nodal architecture is well preserved
- Muscle fibers run parallel to capsule or hilar blood vessels
- Varied patterns of hilar changes:
- Smooth muscle fibers may be densely interwoven within fibrous tissue and hug the hilar nodal capsule
- Smooth muscle fibers may form a loose network extending in all directions within hilar adipose tissue
- Smooth muscle may surround individual islands of fat cells
Microscopic (histologic) images
Images hosted on other servers:
Angiomyomatous hamartoma of lymph node
Positive stains
Negative stains
Differential diagnosis
Additional references
