Bone & joints
Other osteogenic tumors
Osteoid osteoma
Author: David R. Lucas, M.D.
Topic Completed: 1 August 2013
Minor changes: 25 October 2021
Copyright: 2003-2019, PathologyOutlines.com, Inc.
PubMed Search: Osteoid osteoma[title]
Table of Contents
Definition / general | Epidemiology | Sites | Pathophysiology | Clinical features | Diagnosis | Radiology description | Prognostic factors | Case reports | Treatment | Radiology images | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Molecular / cytogenetics description | Differential diagnosisCite this page: Lucas DR. Osteoid osteoma. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/boneosteoidosteoma.html. Accessed October 25th, 2021.
Definition / general
- Small, benign, bone forming tumor associated with pain and limited growth potential
- Nidus < 1.5 cm (any larger size arbitrarily considered to be an osteoblastoma)
Epidemiology
- Children, adolescents and young adults (most patients 5 - 24 years old)
- Male:female ratio 3:1
Sites
- Long bones, especially femur and tibia (50%) most common
- Virtually any bone can be affected
Pathophysiology
- Pain due to production of prostaglandin E2 or nerve fibers in reactive zone (Mod Pathol 1998;11:175)
Clinical features
- Intense localized pain, worse at night, relieved by NSAIDs
- Juxta - articular tumors with arthritis or joint dysfunction
- Vertebral tumors with scoliosis
Diagnosis
- Intense pain and classic radiographic features
Radiology description
- Nidus usually < 1 cm
- Nidus may be radiolucent or ossified and surrounded by a radiolucent halo
- Usually surrounded by dense, reactive osteosclerosis
- Intracortical, subcortical, medullary or bone surface locations
- Long bone tumors often intracortical
- Vertebral tumors in neural arch
Prognostic factors
- Recurrence is rare
- Incompletely excised tumors can recur
Case reports
- 7 year old boy with metachronous osteoid osteomas of tibia and T7 (J Bone Joint Surg Am 2011;93:e73)
- 18 year old woman with calcanial tumor mimicking arthritis (J Foot Ankle Surg 2012;51:237)
Treatment
- CT localization with excision or radiofrequency ablation, or medical management alone (J Bone Joint Surg Am 1992;74:179)
Radiology images
Contributed by Mark R. Wick, M.D. and AFIP images
Femur
Talus
Phalanx
Femoral neck
Images hosted on other servers:
Femur; coronal CT scan shows a radiolucent nidus
Gross description
- Small circumscribed nidus with surrounding sclerosis (intact specimen)
- Most often received as red, gritty fragments post curettage
Gross images
Contributed by Mark R. Wick, M.D., David R. Lucas, M.D. and AFIP images
Various images
Nidus and surrounding sclerosis
Femur
Femur
Microscopic (histologic) description
- Small, circumscribed
- Anastomosing, irregular trabeculae or solid, sclerotic nidus of woven bone with variable mineralization
- Rimmed by single layer of osteoblasts plus frequent osteoclasts
- Loose, fibrovascular stroma
- Surrounded by thick sclerotic bone
- Lymphoplasmacytic synovitis with juxta - articular tumors
Microscopic (histologic) images
Contributed by Mark R. Wick, M.D. and AFIP images
Foot
Various images
Vascular, loosely fibrous stroma
Mature osteoid osteoma
Irregular bony trabeculae
Synovitis
Femur
Images hosted on other servers:
High power
Molecular / cytogenetics description
- Structural alterations involving 22q13.1 identified in two cases (Cancer Genet Cytogenet 2001;124:127)
Differential diagnosis
- Osteoblastoma
- Osteosarcoma
- Reactive bone
