Home   Chapter Home   Jobs   Conferences   Fellowships   Books



Advertisement

Soft tissue tumors

Normal / benign

Glomus tumor


Reviewer: Vijay Shankar, M.D. (see Reviewers page)
Revised: 21 October 2013, last major update November 2012
Copyright: (c) 2003-2013, PathologyOutlines.com, Inc.

See also symplastic

General
=========================================================================

● Usually benign; excision curative
● Occurs in wide age range
● Subungual tumors are exquisitely painful due to abundant nerve fibers
● Arises from modified smooth muscle cells of glomus body, a specialized arteriovenous anastomosis involved in thermoregulation
● Usually under fingernails; also skin, flexor arm/knee, GI tract, rarely in head and neck
● All glomus tumors should have at least focal areas of typical glomus tumor, usually at periphery (Am J Surg Pathol 2001;25:1)

Glomangioma:
● Glomus tumors that resemble cavernous hemangiomas

Glomangiomatosis:
● Diffuse angiomatosis resembling angiomatosis with excess glomus cells
● Often associated with considerable fat and pain
● Probably represents vascular malformations

Glomangiomyoma:
● Combines features of glomus tumor and angioleiomyoma

Glomus tumor of uncertain malignant potential:
● High (5+/50 HPF) mitotic activity and superficial OR 2 cm+ only OR deep only

Glomangiosarcoma:
● Deep (to muscular fascia) and 2 cm or larger OR atypical mitotic figures OR moderate/high nuclear grade and 5+ MF/50 HPF
● 38% had metastases in one series, no metastases in symplastic, uncertain malignant potential, glomangiomatosis

Case reports
=========================================================================

● 24 year old man with glomus tumor of cheek (Case Report Med 2012;2012:307294)
● 42 year old man with painful nodular forearm mass (Case of the Week 289)
● 44 year old man with painful lesion in plantar region (An Bras Dermatol 2011;86:1029)
● 47 year old man with glomangiosarcoma of shoulder (dermpathMD)
● 50 year old woman with primary glomus tumor of liver (Indian J Pathol Microbiol 2011;54:584)

Clinical images
=========================================================================


Thumb #1

#2

Index finger

Plantar nodule

Gross description
=========================================================================

● Less than 1 cm, rounded, red-blue, yellowish to tan red, firm
● Resembles fresh hemorrhage under the nail

Gross images
=========================================================================


Liver tumor

Micro description
=========================================================================

● Branching vascular channels separated by stroma containing glomus cells in nests, aggregates
● Glomus cells are arranged around vessels
● Have small, regular, round, indistinct nucleoli
● More infiltrative in children
● May have secondary myxoid change
● Very low mitotic activity

Micro images
=========================================================================


Index finger tumor


Thumb

Liver

Cheek is benign but invades vessel wall

Plantar nodule is SMA+

Glomangiosarcoma of shoulder

Forearm mass






Alpha-smooth muscle actin

CD31

Cytology description
=========================================================================

● Cohesive clusters of uniform round cells with scanty cytoplasm
● Background of scattered amorphous magenta colored material, blood and occasional inflammatory cells (J Cytol 2010;27:104)

Cytology images
=========================================================================


Round to oval cells with homogenous granular chromatin

Positive stains
=========================================================================

● Smooth muscle actin, type 4 collagen, vimentin
● CD34 in 20% only
● Variable expression of h-caldesmon and calponin

Negative stains
=========================================================================

● Cytokeratin, desmin, S100, chromogranin

Electron microscopy description
=========================================================================

● Resemble smooth muscle cells


Symplastic glomus tumor

General
=========================================================================

● High nuclear grade but no mitotic figures or other features of malignancy; may be degenerative

Case reports
=========================================================================

● 78 year old male with nail deformity of indx finger (J Cutan Pathol 2009;36:1099)
● 81 year old man with mass in subcutis of great toe (Case of Week #238)

Micro images
=========================================================================



(a) multiple foci of glomus cells surrounding capillary-sized vessels in myxoid stroma with some nerve fibers and bone
(b) glomus cells show prominent cytological atypia with nuclear enlargement and pleomorphism, anisonucleosis, hyperchromasia, pseudoinclusions, bizarre nuclei, coarse chromatin, and irregular nuclear membrane


Images from Case of the Week #238:










CD34

Ki-67

Smooth muscle actin

Vimentin

Desmin

End of Soft tissue tumors > Normal / benign > Glomus tumor


This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).