title: Tumoral calcinosis of the spine: a study of 21 cases.
abstract: METHODS
  A retrospective study was conducted to investigate 21 patients found during spinal surgery to have paraspinal masses of dystrophic calcification (tumoral calcinosis).
  
  
  OBJECTIVE
  To determine the magnetic resonance imaging characteristics of this disorder, and to document the associated spinal pathology.
  
  
  BACKGROUND
  Tumoral calcinosis usually is associated with hereditary disorders of calcium metabolism or renal dialysis. It also occurs in degenerated tissues in the absence of systemic disorders. Characteristically, calcific masses in the appendicular skeleton are visible on plain radiographs. Tumoral calcinosis has only rarely been reported in the spine. Documented patients have had an obvious calcific mass, and almost always the disorder has existed in other locations as well. Careful histologic study of specimens removed during spinal surgery suggests that tumoral calcinosis is common in the spine and usually is secondary to preexisting pathology.
  
  
  METHODS
  This study involved 21 patients with lesions of tumoral calcinosis identified by histopathologic analysis of specimens removed during spinal surgery. The magnetic resonance images and the plain radiographs of the patients were reviewed and correlated with their clinical histories.
  
  
  RESULTS
  In all the patients, the lesion of tumoral calcinosis was associated with a mass lesion seen on magnetic resonance imaging. Calcific masses were not apparent on plain films. In no case was the mass diagnosed before surgery as tumoral calcinosis. The magnetic resonance imaging changes were variously misinterpreted as neoplasms, infections, extruded disc material, or cysts. The observed features of tumoral calcinosis were those of an extradural mass showing a heterogeneous mixed-signal lesion that was identical on T1- and T2-weighted images. Characteristically, gadolinium did not enhance the lesions.
  
  
  CONCLUSIONS
  Awareness of tumoral calcinosis of the spine may prevent unwarranted diagnoses of a more serious lesion in patients with characteristic magnetic resonance imaging changes. Also, this awareness may prevent pathologists from interpreting lesional tissue as nondiagnostic when other diagnoses are suspected clinically. This process may be a manifestation of degenerative spinal disease that has become so dominant that the underlying processes are obscured.
authors.affiliation: Johns Hopkins School of Medicine, the Department of Pathology, Johns Hopkins Hospital, Baltimore, Maryland, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Durant
authors.forename: L H
authors.initials: LH
authors.lastname: Riley
authors.forename: P C
authors.initials: PC
authors.lastname: Burger
authors.forename: E F
authors.initials: EF
authors.lastname: McCarthy
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002114:Calcinosis / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008661:Metabolism, Inborn Errors / Q000150:complications / Q000473:pathology; D008875:Middle Aged; D011859:Radiography; D006435:Renal Dialysis / Q000009:adverse effects; D051437:Renal Insufficiency / Q000150:complications / Q000473:pathology; D012189:Retrospective Studies; D013122:Spinal Diseases / Q000175:diagnosis* / Q000209:etiology; D013131:Spine / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery