title: Mammographic features and histopathological findings of interval breast cancers.
abstract: BACKGROUND
  Interval cancers are considered a shortcoming in screening mammography due to less favorable prognostic tumor characteristics compared to screening-detected cancers and consequently a lower chance of survival from the disease.
  
  
  OBJECTIVE
  To describe the mammographic features and prognostic histopathological tumor characteristics of interval breast cancers.
  
  
  METHODS
  A total of 231 interval breast cancer cases diagnosed in prevalently screened women aged 50-69 years old were examined. Thirty-five percent of the cases were retrospectively classified as missed cancers, 23% as minimal sign, and 42% as true negative (including occult cancers) in a definitive classification performed by six experienced breast radiologists. The retrospective classification described the mammographic features of the baseline screening mammograms in missed and minimal-sign interval cancers, while histopathological reports were used to describe the tumor characteristics in all the subgroups of interval cancers.
  
  
  RESULTS
  Fifty percent of the missed and minimal-sign interval cancers combined presented poorly defined mass or asymmetric density, and 26% calcifications with or without associated density or mass at baseline screening. Twenty-seven percent of invasive tumors were <15 mm for missed and 47% for true interval cancers (P<0.001). Lymph node involvement was more common in missed (49%) compared with the true cases (33%, P<0.05).
  
  
  CONCLUSIONS
  Missed interval cancers have less prognostically favorable histopathological tumor characteristics compared with true interval cancers. Improving the radiologist's perception and interpretation by establishing systematic collection of features and implementation of organized reviews may decrease the number of interval cancers in a screening program.
authors.affiliation: Department of Screening-Based Research, Cancer Registry of Norway, Oslo, Norway. solveig.hofvind@kreftregisteret.no
authors.forename: S
authors.initials: S
authors.lastname: Hofvind
authors.forename: B
authors.initials: B
authors.lastname: Geller
authors.forename: P
authors.initials: P
authors.lastname: Skaane
mesh_terms: D000368:Aged; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D005188:False Negative Reactions; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging; D008327:Mammography; D008403:Mass Screening; D008875:Middle Aged; D012189:Retrospective Studies; D013997:Time Factors
references.citation: Breast. 2007 Dec;16(6):646-52
references.pmid: 17624779
references.citation: Eur Radiol. 1999;9(3):460-9
references.pmid: 10087117
references.citation: J Natl Cancer Inst. 1999 Dec 1;91(23):2020-8
references.pmid: 10580027
references.citation: Eur Radiol. 2002 Nov;12(11):2679-83
references.pmid: 12386757
references.citation: Eur J Epidemiol. 2007;22(7):447-55
references.pmid: 17594526
references.citation: Eur Radiol. 2006 Jul;16(7):1449-60
references.pmid: 16416275
references.citation: Eur Radiol. 1998;8(4):639-46
references.pmid: 9569340
references.citation: Cancer. 1996 Sep 15;78(6):1220-8
references.pmid: 8826943
references.citation: Int J Cancer. 2006 Sep 1;119(5):1158-63
references.pmid: 16570280
references.citation: J Med Screen. 2006;13(3):115-22
references.pmid: 17007651
references.citation: J Med Screen. 2000;7(1):19-23
references.pmid: 10807142
references.citation: J Med Screen. 2005;12(1):43-9
references.pmid: 15814019
references.citation: AJR Am J Roentgenol. 2007 Feb;188(2):377-84
references.pmid: 17242245
references.citation: J Med Screen. 1999;6(1):35-9
references.pmid: 10321369
references.citation: Eur J Radiol. 2007 Feb;61(2):192-4
references.pmid: 17164080
references.citation: N Engl J Med. 2007 Apr 5;356(14):1399-409
references.pmid: 17409321
references.citation: Radiology. 1986 Aug;160(2):289-93
references.pmid: 3726103
references.citation: Int J Cancer. 2001 Nov;94(4):594-8
references.pmid: 11745450
references.citation: AJR Am J Roentgenol. 1986 Apr;146(4):661-3
references.pmid: 3485337
references.citation: Radiology. 2006 Oct;241(1):67-75
references.pmid: 16990672
references.citation: Ann Oncol. 2008 Apr;19(4):614-22
references.pmid: 18024988
references.citation: Radiology. 2006 Oct;241(1):55-66
references.pmid: 16990671
references.citation: AJR Am J Roentgenol. 1984 Sep;143(3):461-4
references.pmid: 6331721
references.citation: J Med Screen. 2007;14(3):138-43
references.pmid: 17925086
references.citation: Radiology. 2005 Nov;237(2):437-43
references.pmid: 16244251
references.citation: J Natl Cancer Inst. 2005 Aug 17;97(16):1195-203
references.pmid: 16106024
references.citation: Eur J Cancer. 2003 Aug;39(12):1770-5
references.pmid: 12888373
references.citation: Radiology. 1992 Sep;184(3):613-7
references.pmid: 1509041
references.citation: Clin Radiol. 2006 Sep;61(9):784-8
references.pmid: 16905387