Brief observations
Conventional Cancer Screening versus PET/CT in Dermatomyositis/Polymyositis

https://doi.org/10.1016/j.amjmed.2009.11.012Get rights and content

Abstract

Objective

To determine the value of whole-body [18F] fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for diagnosing occult malignant disease in patients with myositis compared with broad conventional cancer screening.

Methods

We prospectively studied 55 consecutive patients with a recent diagnosis of myositis in 3 teaching hospitals over a 3-year period by whole-body FDG-PET/CT and compared the results with those of conventional cancer screening, which included thoracoabdominal CT, mammography, gynecologic examination, ultrasonography, and tumor marker analysis. Comparisons were made using predictive values and their 95% confidence intervals.

Results

A total of 9 of 55 patients were diagnosed with paraneoplastic myositis. FDG uptake was positive in 7 patients (1 false-positive), negative in 44 patients (3 false-negative), and inconclusive in 4 patients. Positive and negative predictive values of FDG-PET/CT for the diagnosis of cancer were 85.7% and 93.8%, respectively. Conventional screening was cancer-positive in 9 patients (2 false-positive) and negative in the remaining 46 patients (2 false-negative). Positive and negative predictive values were 77.8% and 95.7%, respectively. The overall predictive value of broad conventional screening was the same as that of FDG-PET/CT (92.7 vs 92.7).

Conclusion

The performance of FDG-PET/CT, a single imaging study, for diagnosing occult malignant disease in patients with myositis was comparable to that of broad conventional screening, which includes multiple tests.

Section snippets

Patients

The study included 55 consecutive adult white patients who were recently diagnosed with dermatomyositis/polymyositis, consulting at 3 tertiary teaching hospitals in Barcelona (Vall d'Hebron General Hospital, Bellvitge Hospital, and Hospital Clinic) between February 2006 and January 2009. Altogether, these referral hospitals have 2500 beds for a catchment population of approximately 2.5 million inhabitants. Patients included in the study gave informed written consent to undergo FDG-PET/CT. The

Results

Between February 2006 and January 2009, 55 consecutive patients, 37 women and 18 men, with a median (interquartile range) age of 57.5 (46.1-68.9) years, were diagnosed with inflammatory myopathy (6 polymyositis/49 dermatomyositis). The median (interquartile range) duration of follow-up of patients with a negative or inconclusive FDG-PET/CT report was 14 (8-30) months. Nine patients were diagnosed with paraneoplastic myositis (16%). The tumor was located in the breast in 5 patients and in the

Discussion

In this prospective multicenter study including 55 consecutive patients with dermatomyositis/polymyositis, whole-body FDG-PET/CT scanning was comparable to conventional cancer screening for detecting occult malignant disease. The study included all patients diagnosed with dermatomyositis and polymyositis in our area over a 3-year period. The number of cases that occurred in that time is in keeping with our previously reported epidemiologic data,18 and therefore a population selection bias seems

References (24)

  • M.C. Dalakas et al.

    Polymyositis and dermatomyositis

    Lancet

    (2003)
  • R.R. Patel et al.

    Occult malignancy in patients with suspected paraneoplastic neurologic syndromes: value of positron emission tomography in diagnosis

    Mayo Clin Proc

    (2008)
  • R. Buchbinder et al.

    Incidence of malignant disease in biopsy-proven inflammatory myopathyA population-based cohort study

    Ann Intern Med

    (2001)
  • B. Sigurgeirsson et al.

    Risk of cancer in patients with dermatomyositis or polymyositisA population-based study

    N Engl J Med

    (1992)
  • L.A. Drake et al.

    Guidelines of care for dermatomyositis

    J Am Acad Dermatol

    (1996)
  • A. Sparsa et al.

    Routine vs extensive malignancy search for adult dermatomyositis and polymyositis: a study of 40 patients

    Arch Dermatol

    (2002)
  • Z. Amoura et al.

    Tumor antigen markers for the detection of solid cancers in inflammatory myopathies

    Cancer Epidemiol Biomarkers Prev

    (2005)
  • S.M. Levine

    Cancer and myositis: new insights into an old association

    Curr Opin Rheumatol

    (2006)
  • J.H. Rees et al.

    The role of [18F] fluoro-2-deoxyglucose-PET scanning in the diagnosis of paraneoplastic neurological disorders

    Brain

    (2001)
  • S. Younes-Mhenni et al.

    FDG-PET improves tumour detection in patients with paraneoplastic neurological syndromes

    Brain

    (2004)
  • R. Linke et al.

    Antibody-positive paraneoplastic neurologic syndromesValue of CT and PET for tumor diagnosis

    Neurology

    (2004)
  • M. Hadjivassiliou et al.

    PET scan in clinically suspected paraneoplastic neurological syndromes: a 6-year prospective study in a regional neuroscience unit

    Acta Neurol Scand

    (2009)
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    Funding: This study was funded in part by a grant (FIS/2008 PI 08-0450) from the Spanish Ministry of Health and Consumer Affairs.

    Conflict of Interest: None of the authors have any conflicts of interest associated with the work presented in this manuscript.

    Authorship: All authors had access to the data and played a role in writing this manuscript.

    Drs Albert Selva-O'Callaghan and Josep Ma Grau contributed equally to this work.

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