title: Rate of Distant Metastases on 18F-FDG PET/CT at Initial Staging of Breast Cancer: Comparison of Women Younger and Older Than 40 Years.
abstract: Women who have breast cancer and are younger than 40 y have a poorer outcome than older women. A higher rate of undetected metastases at the time of diagnosis in younger women has been proposed to account for this difference. Our main objective was to test this hypothesis by comparing the distant metastasis rate (DMR) on initial18F-FDG PET/CT in a group of breast cancer patients younger than 40 y (<40 y group) with that in a group of breast cancer patients older than 40 y (≥40 y group). An assessment of associations between distant metastases and tumor characteristics was a second objective of the present study.
  
  
  
  A retrospective single-institution study was performed on women who had breast cancer and no prior malignancy, who were asymptomatic for metastatic lesions on initial clinical examination, and who had initial18F-FDG PET/CT within 3 mo after pathologic breast cancer diagnosis and before initial treatment. On the basis of these criteria, data for 2 groups of women differing only in age (<40 y and ≥40 y) were extracted from the hospital information system of Curie Institute-Paris.18F-FDG PET/CT examinations were reviewed, and the DMR was recorded for each clinical stage subgroup (stages I-III).
  
  
  
  For each group (<40 y and ≥40 y), 107 patients were included, with the same number of patients in each clinical stage subgroup (12 stage I patients, 32 stage IIA patients, 30 stage IIB patients, and 33 stage III patients). The ages of the patients (mean ± SD) were 34.5 ± 4.0 y (<40 y group) and 56.0 ± 10.7 y (≥40 y group). No significant difference in DMRs was observed between the <40 y group and the ≥40 y group (DMRs, 21% and 22%, respectively; P = 1). The DMRs in patients not selected for age were 8% for stage I, 11% for stage IIA, 15% for stage IIB, and 44% for stage III.
  
  
  
  The DMR was not significantly higher in younger breast cancer patients (<40 y) than in older breast cancer patients (≥40 y), ruling out the assumption that undetected metastases at diagnosis explain the poorer outcome of younger women. However, our results highlight the high yield of18F-FDG PET/CT for initial breast cancer staging, even in stage II patients, whatever their age.
authors: Service de Médecine Nucléaire, Institut Curie, Paris, France vincent.lebon@cea.fr.
authors: Vincent
authors: V
authors: Lebon
authors: Service de Médecine Nucléaire, Institut Curie, Saint-Cloud, France.|Faculté de Médecine, Université Versailles Saint-Quentin, Versailles, France.
authors: Jean-Louis
authors: JL
authors: Alberini
authors: Département d'Oncologie Médicale, Institut Curie, Paris, France; and.|Faculté de Médecine, Université Paris-Descartes, Paris, France.
authors: Jean-Yves
authors: JY
authors: Pierga
authors: Département d'Oncologie Médicale, Institut Curie, Paris, France; and.
authors: Véronique
authors: V
authors: Diéras
authors: Service de Médecine Nucléaire, Institut Curie, Paris, France.
authors: Nina
authors: N
authors: Jehanno
authors: Service de Médecine Nucléaire, Institut Curie, Paris, France.
authors: Myriam
authors: M
authors: Wartski
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000473:pathology*; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000473:pathology* / Q000556:secondary*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005602:France / Q000453:epidemiology; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D000072078:Positron Emission Tomography Computed Tomography / Q000706:statistics & numerical data*; D015995:Prevalence; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012307:Risk Factors; D012680:Sensitivity and Specificity
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: 18F-FDG; PET; age; breast cancer; metastases