title: Evaluation of inadequate, indeterminate, false-negative and false-positive cases in cytological examination for breast cancer according to histological type.
abstract: BACKGROUND
  We previously investigated the current status of breast cytology cancer screening at seven institutes in our area of southern Fukuoka Prefecture, and found some differences in diagnostic accuracy among the institutions. In the present study, we evaluated the cases involved and noted possible reasons for their original cytological classification as inadequate, indeterminate, false-negative and false-positive according to histological type.
  
  
  METHODS
  We evaluated the histological findings in 5693 individuals who underwent cytological examination for breast cancer (including inadequate, indeterminate, false-negative and false-positive cases), to determine the most common histological types and/or features in these settings and the usefulness/limitations of cytological examination for the diagnosis of breast cancer.
  
  
  RESULTS
  Among 1152 cytologically inadequate cases, histology revealed that 75/173 (43.6%) cases were benign, including mastopathy (fibrocystic disease) in 38.6%, fibroadenoma in 24.0% and papilloma in 5.3%. Ninety-five of 173 (54.9%) cases were histologically malignant, with scirrhous growing type, invasive ductal carcinoma (SIDC) being significantly more frequent (49.5%) than papillotubular growing type (Papi-tub) (P < 0.0001), solid-tubular growing type (P = 0.0001) and ductal carcinoma in situ (DCIS) (P = 0.0001). Among 458 indeterminate cases, 54/139 (38.8%) were histologically benign (mastopathy, 30.0%; fibroadenoma, 27.8%; papilloma, 26.0%) and 73/139 (52.5%) were malignant, with SIDC being the most frequent malignant tumor (37.0%). Among 52 false-negative cases, SIDC was significantly more frequent (42.3%) than DCIS (P = 0.0049) and Papi-tub (P = 0.001). There were three false-positive cases, with one each of fibroadenoma, epidermal cyst and papilloma.
  
  
  CONCLUSIONS
  The inadequate, indeterminate, false-negative and false-positive cases showed similar histological types, notably SIDC for malignant tumors, and mastopathy, fibroadenoma and papilloma for benign cases. We need to pay particular attention to the collection and assessment of aspirates for these histological types of breast disease. In particular, several inadequate, indeterminate and false-negative cases with samples collected by aspiration were diagnosed as SIDC. These findings should encourage the use of needle biopsy rather than aspiration when this histological type is identified on imaging. Namely, good communication between clinicians and pathological staff, and triple assessment (i.e., clinical, pathological and radiological assessment), are important for accurate diagnosis of aspiration samples.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/7349809170055423.
authors.affiliation: Department of Pathology, Kurume University Medical Center, Kurume, Japan. rin@med.kurume-u.ac.jp
authors.forename: Rin
authors.initials: R
authors.lastname: Yamaguchi
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Tsuchiya
authors.forename: Takashi
authors.initials: T
authors.lastname: Koshikawa
authors.forename: Toshiro
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Kuniko
authors.initials: K
authors.lastname: Mibuchi
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nonaka
authors.forename: Sonoe
authors.initials: S
authors.lastname: Ito
authors.forename: Hidejiro
authors.initials: H
authors.lastname: Higuchi
authors.forename: Mariko
authors.initials: M
authors.lastname: Nagao
authors.forename: Koichi
authors.initials: K
authors.lastname: Higaki
authors.forename: Jiro
authors.initials: J
authors.lastname: Watanabe
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kage
authors.forename: Hirohisa
authors.initials: H
authors.lastname: Yano
mesh_terms: D002293:Adenocarcinoma, Scirrhous / Q000473:pathology; D001707:Biopsy, Needle; D001943:Breast Neoplasms / Q000145:classification / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000473:pathology; D016009:Chi-Square Distribution; D003584:Cytological Techniques; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D018226:Fibroadenoma / Q000473:pathology; D005348:Fibrocystic Breast Disease / Q000473:pathology*; D006801:Humans; D007564:Japan; D010212:Papilloma / Q000473:pathology; D011237:Predictive Value of Tests